Oct 1, 2008
Reset your forgotten Windows password
Reset your forgotten Windows password
Have you forgotten your recently changed Windows password and do not have a password reset disk then don't worry.Just follow these steps.
* Boot from your Windows CD
* When you get to the Welcome screen, press ENTER to Setup Windows now
* Select your windows partition that you want to reset the password.Continue until you reach the "Press R to begin repair process".
* Press R and the setup will start copying files
* On the next automated reboot "Do not press any key when asked to boot from CD"
* When you see the Installing Devices progress bar, press SHIFT + F10. A command console will now open up giving you a wide access to the system
* Type NUSRMGR.CPL and press Enter.This will give you Graphical access to User accounts in control panel.
* Change or reset your passwords suitably.
Your programs and personalized settings will not be changed.If you have any problems then feel free to comment here.
Have you forgotten your recently changed Windows password and do not have a password reset disk then don't worry.Just follow these steps.
* Boot from your Windows CD
* When you get to the Welcome screen, press ENTER to Setup Windows now
* Select your windows partition that you want to reset the password.Continue until you reach the "Press R to begin repair process".
* Press R and the setup will start copying files
* On the next automated reboot "Do not press any key when asked to boot from CD"
* When you see the Installing Devices progress bar, press SHIFT + F10. A command console will now open up giving you a wide access to the system
* Type NUSRMGR.CPL and press Enter.This will give you Graphical access to User accounts in control panel.
* Change or reset your passwords suitably.
Your programs and personalized settings will not be changed.If you have any problems then feel free to comment here.
Read Deleted SMS Read Deleted SMS!!
Read Deleted SMS!!
A SMS once deleted can’t be read again….but sometimes we hurrily delete some important SMS
Here is the technique that must be followed to retrieve deleted SMS.
Required utility:
1) Any system explorer or file explorer program (eg. fileman or fexplorer.provided with the package)
Step 1) Open FexplorerStep
2) Select drive C: or D: depending on the memory in which the Sms messages have been saved.
Step 3) For example u selected c: , Then open “system” folder.
step 4) Then in “system” folder open “mail” folder.
step 5) Then in this folder u will see different folders (eg 0010001_s) and certain files (eg 00100000). These files are the actual messages. Browse through every folder and open all files till u get the sms u are looking for.
Step 6) For opening the files don’t choose options>file>open as it will show format not supported rather choose options>file>hex/text viewer.
By selecting the “Hex/ text viewer” u ll be able to open and read the deleted SMS message
A SMS once deleted can’t be read again….but sometimes we hurrily delete some important SMS
Here is the technique that must be followed to retrieve deleted SMS.
Required utility:
1) Any system explorer or file explorer program (eg. fileman or fexplorer.provided with the package)
Step 1) Open FexplorerStep
2) Select drive C: or D: depending on the memory in which the Sms messages have been saved.
Step 3) For example u selected c: , Then open “system” folder.
step 4) Then in “system” folder open “mail” folder.
step 5) Then in this folder u will see different folders (eg 0010001_s) and certain files (eg 00100000). These files are the actual messages. Browse through every folder and open all files till u get the sms u are looking for.
Step 6) For opening the files don’t choose options>file>open as it will show format not supported rather choose options>file>hex/text viewer.
By selecting the “Hex/ text viewer” u ll be able to open and read the deleted SMS message
How to crack any type of Software Protection
Softwares you need : - W32Dasm and HIEW
Identifying the protection : ====>>>>
Run the program, game, etc., (SoftwareX) that you want to crack without the CD in the CD reader. SoftwareX will not run of course, however, when the error window pops up it will give you all of the vital information that you need to crack the program, so be sure to
write down what it says.
Cracking the Protection : ====>>>>
Now, run Win32Dasm. On the file menu open DISASSEMBLER > OPEN FILE TO DISASSEMBLE. Select SoftwareX’s executable file in the popup window that will appear (e.g. SoftwareX.exe). W32Dasm may take several minutes to disassemble the file.
When W32Dasm finishes disassembling the file it will display unrecognizable text; this is what we want. Click on the String Data References button. Scroll through the String Data Items until you find SoftwareX’s error message. When you locate it, double click the
error message and then close the window to return to the Win32Dasm text. You will notice that you have been moved somewhere within the SoftwareX’s check routine; this is where the error message in generated.
Now comes the difficult part, so be careful. To crack SoftwareX’s protection you must know the @offset of every call and jump command. Write down every call and jump @offset number that you see (You have to be sure, that the OPBAR change its used color to green). You need the number behind the @offset without the “h.”
Now open HIEW, locate SoftwareX’s executable, and press the F4 key. At this point a popup window will appear with 3 options: Text, Hex, and Decode. Click on “Decode” to see a list of numbers. Now press the F5 key and enter the number that was extracted using Win32Dasm. After you have entered the number you will be taken to SoftwareX’s check routine within HIEW.
To continue you must understand this paragraph. If the command that you are taken to is E92BF9BF74, for example, it means that the command equals 5 bytes. Every 2 digits equal one byte: E9-2B-F9-BF-74 => 10 digits => 5 bytes.
If you understood this then you can continue.
Press F3 (Edit), this will allow you to edit the 10 digits. Replace the 5 bytes with the digits 90. In other words, E92BF9BF74 will become 9090909090 (90-90-90-90-90). After you complete this step press the F10 key to exit.
Identifying the protection : ====>>>>
Run the program, game, etc., (SoftwareX) that you want to crack without the CD in the CD reader. SoftwareX will not run of course, however, when the error window pops up it will give you all of the vital information that you need to crack the program, so be sure to
write down what it says.
Cracking the Protection : ====>>>>
Now, run Win32Dasm. On the file menu open DISASSEMBLER > OPEN FILE TO DISASSEMBLE. Select SoftwareX’s executable file in the popup window that will appear (e.g. SoftwareX.exe). W32Dasm may take several minutes to disassemble the file.
When W32Dasm finishes disassembling the file it will display unrecognizable text; this is what we want. Click on the String Data References button. Scroll through the String Data Items until you find SoftwareX’s error message. When you locate it, double click the
error message and then close the window to return to the Win32Dasm text. You will notice that you have been moved somewhere within the SoftwareX’s check routine; this is where the error message in generated.
Now comes the difficult part, so be careful. To crack SoftwareX’s protection you must know the @offset of every call and jump command. Write down every call and jump @offset number that you see (You have to be sure, that the OPBAR change its used color to green). You need the number behind the @offset without the “h.”
Now open HIEW, locate SoftwareX’s executable, and press the F4 key. At this point a popup window will appear with 3 options: Text, Hex, and Decode. Click on “Decode” to see a list of numbers. Now press the F5 key and enter the number that was extracted using Win32Dasm. After you have entered the number you will be taken to SoftwareX’s check routine within HIEW.
To continue you must understand this paragraph. If the command that you are taken to is E92BF9BF74, for example, it means that the command equals 5 bytes. Every 2 digits equal one byte: E9-2B-F9-BF-74 => 10 digits => 5 bytes.
If you understood this then you can continue.
Press F3 (Edit), this will allow you to edit the 10 digits. Replace the 5 bytes with the digits 90. In other words, E92BF9BF74 will become 9090909090 (90-90-90-90-90). After you complete this step press the F10 key to exit.
Does your computer connect to websites secretly
Does your computer connect to websites secretly
Some programs running in the background of your computer might be secretely
connecting to other websites secretly and downloading unwanted data's and
your connection speed might become much slower.
Use this hidden command prompt trick to find out.
Open command prompt from the Start Menu.
Type "netstat -b 5 > sectretlog.txt"
After the time you wish to monitor press Ctrl+C.
Type sectretlog.txt in the command line as in the screenshot shown above.A
notepad similar to below will popup.
notepad
This file secretlog.txt conatains the list of programs that tried to connect to the
internet.You can look for any suspicious programs or hacktools in this list and
filter it out or remove it.
Some programs running in the background of your computer might be secretely
connecting to other websites secretly and downloading unwanted data's and
your connection speed might become much slower.
Use this hidden command prompt trick to find out.
Open command prompt from the Start Menu.
Type "netstat -b 5 > sectretlog.txt"
After the time you wish to monitor press Ctrl+C.
Type sectretlog.txt in the command line as in the screenshot shown above.A
notepad similar to below will popup.
notepad
This file secretlog.txt conatains the list of programs that tried to connect to the
internet.You can look for any suspicious programs or hacktools in this list and
filter it out or remove it.
Make Your Windows Fast
Disable CD Autorun
( WinXP PRO Only)
1) Click Start, Run and enter GPEDIT.MSC
2) Go to Computer Configuration, Administrative Templates, System.
3) Locate the entry for Turn autoplay off and modify it as you desire.
Speed Up Browsing
When you connect to a web site your computer sends information back and forth. Some of this information deals with resolving the site name to an IP address, the stuff that TCP/IP really deals with, not words. This is DNS information and is used so that you will not need to ask for the site location each and every time you visit the site. Although Windows XP and Windows XP have a pretty efficient DNS cache, you can increase its overall performance by increasing its size. You can do this with the registry entries below:
Windows Registry Editor Version 5.00
[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Dnscache\Parameters]
"CacheHashTableBucketSize"=dword:00000001
"CacheHashTableSize"=dword:00000180
"MaxCacheEntryTtlLimit"=dword:0000fa00
"MaxSOACacheEntryTtlLimit"=dword:0000012d
Make a new text file and rename it to dnscache.reg. Then copy and paste the above into it and save it. Merge it into the registry.
DISABLE INDEXING SERVICES
Indexing Services is a small little program that uses large amounts of RAM and can often make a computer endlessly loud and noisy. This system process indexes and updates lists of all the files that are on your computer. It does this so that when you do a search for something on your computer, it will search faster by scanning the index lists. If you don't search your computer often, or even if you do search often, this system service is completely unnecessary. To disable do the following:
1. Go to Start
2. Click Settings
3. Click Control Panel
4. Double-click Add/Remove Programs
5. Click the Add/Remove Window Components
6. Uncheck the Indexing services
7. Click Next
OPTIMISE DISPLAY SETTINGS
Windows XP can look sexy but displaying all the visual items can waste system resources. To optimize:
1.Go to Start
2. Click Settings
3. Click Control Panel
4. Click System
5. Click Advanced tab
6. In the Performance tab click Settings
7. Leave only the following ticked:
- Show shadows under menus
- Show shadows under mouse pointer
- Show translucent selection rectangle
- Use drop shadows for icons labels on the desktop
- Use visual styles on windows and buttons
SPEEDUP FOLDER BROWSING
You may have noticed that everytime you open my computer to browse folders that there is a slight delay. This is because Windows XP automatically searches for network files and printers everytime you open Windows Explorer. To fix this and to increase browsing significantly:
1. Open My Computer
2. Click on Tools menu
3. Click on Folder Options
4. Click on the View tab.
5. Uncheck the Automatically search for network folders and printers check box
6. Click Apply
7. Click Ok
8. Reboot your computer
REMOVE THE DESKTOP PICTURE
Your desktop background consumes a fair amount of memory and can slow the loading time of your system. Removing it will improve performance.
1. Right click on Desktop and select Properties
2. Select the Desktop tab
3. In the Background window select None
4. Click Ok
DISABLE UNNECESSARY SERVICES
Because Windows XP has to be all things to all people it has many services running that take up system resources that you will never need. Below is a list of services that can be disabled on most machines:
Alerter
Clipbook
Computer Browser
Distributed Link Tracking Client
Fast User Switching
Help and Support - (If you use Windows Help and Support leave this enabled)
Human Interface Access Devices
Indexing Service
IPSEC Services
Messenger
Netmeeting Remote Desktop Sharing (disabled for extra security)
Portable Media Serial Number
Remote Desktop Help Session Manager (disabled for extra security)
Remote Procedure Call Locator
Remote Registry (disabled for extra security)
Remote Registry Service
Secondary Logon
Routing & Remote Access (disabled for extra security)
Server
SSDP Discovery Service - (Unplug n' Pray will disable this)
Telnet
TCP/IP NetBIOS Helper
Upload Manager
Universal Plug and Play Device Host
Windows Time
Wireless Zero Configuration (Do not disable if you use a wireless network)
Workstation
To disable these services:
Go to Start and then Run and type "services.msc"
Doubleclick on the service you want to change
Change the startup type to 'Disable"
REMOVE ANNOYING DELETE CONFIRMATION MESSAGES
Although not strictly a performance tweak I love this fix as it makes my machine 'feel' faster. I hate the annoying 'are you sure?' messages that XP displays, especially if I have to use a laptop touchpad to close them. To remove these messages:
1. Right-click on the 'Recycle Bin' on the desktop and then click 'Properties'
2. Clear the 'Display Delete Confirmation Dialog' check box and click 'Ok'
If you do accidently delete a file don't worry as all is not lost. Just go to your Recycle Bin and 'Restore' the file.
( WinXP PRO Only)
1) Click Start, Run and enter GPEDIT.MSC
2) Go to Computer Configuration, Administrative Templates, System.
3) Locate the entry for Turn autoplay off and modify it as you desire.
Speed Up Browsing
When you connect to a web site your computer sends information back and forth. Some of this information deals with resolving the site name to an IP address, the stuff that TCP/IP really deals with, not words. This is DNS information and is used so that you will not need to ask for the site location each and every time you visit the site. Although Windows XP and Windows XP have a pretty efficient DNS cache, you can increase its overall performance by increasing its size. You can do this with the registry entries below:
Windows Registry Editor Version 5.00
[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Dnscache\Parameters]
"CacheHashTableBucketSize"=dword:00000001
"CacheHashTableSize"=dword:00000180
"MaxCacheEntryTtlLimit"=dword:0000fa00
"MaxSOACacheEntryTtlLimit"=dword:0000012d
Make a new text file and rename it to dnscache.reg. Then copy and paste the above into it and save it. Merge it into the registry.
DISABLE INDEXING SERVICES
Indexing Services is a small little program that uses large amounts of RAM and can often make a computer endlessly loud and noisy. This system process indexes and updates lists of all the files that are on your computer. It does this so that when you do a search for something on your computer, it will search faster by scanning the index lists. If you don't search your computer often, or even if you do search often, this system service is completely unnecessary. To disable do the following:
1. Go to Start
2. Click Settings
3. Click Control Panel
4. Double-click Add/Remove Programs
5. Click the Add/Remove Window Components
6. Uncheck the Indexing services
7. Click Next
OPTIMISE DISPLAY SETTINGS
Windows XP can look sexy but displaying all the visual items can waste system resources. To optimize:
1.Go to Start
2. Click Settings
3. Click Control Panel
4. Click System
5. Click Advanced tab
6. In the Performance tab click Settings
7. Leave only the following ticked:
- Show shadows under menus
- Show shadows under mouse pointer
- Show translucent selection rectangle
- Use drop shadows for icons labels on the desktop
- Use visual styles on windows and buttons
SPEEDUP FOLDER BROWSING
You may have noticed that everytime you open my computer to browse folders that there is a slight delay. This is because Windows XP automatically searches for network files and printers everytime you open Windows Explorer. To fix this and to increase browsing significantly:
1. Open My Computer
2. Click on Tools menu
3. Click on Folder Options
4. Click on the View tab.
5. Uncheck the Automatically search for network folders and printers check box
6. Click Apply
7. Click Ok
8. Reboot your computer
REMOVE THE DESKTOP PICTURE
Your desktop background consumes a fair amount of memory and can slow the loading time of your system. Removing it will improve performance.
1. Right click on Desktop and select Properties
2. Select the Desktop tab
3. In the Background window select None
4. Click Ok
DISABLE UNNECESSARY SERVICES
Because Windows XP has to be all things to all people it has many services running that take up system resources that you will never need. Below is a list of services that can be disabled on most machines:
Alerter
Clipbook
Computer Browser
Distributed Link Tracking Client
Fast User Switching
Help and Support - (If you use Windows Help and Support leave this enabled)
Human Interface Access Devices
Indexing Service
IPSEC Services
Messenger
Netmeeting Remote Desktop Sharing (disabled for extra security)
Portable Media Serial Number
Remote Desktop Help Session Manager (disabled for extra security)
Remote Procedure Call Locator
Remote Registry (disabled for extra security)
Remote Registry Service
Secondary Logon
Routing & Remote Access (disabled for extra security)
Server
SSDP Discovery Service - (Unplug n' Pray will disable this)
Telnet
TCP/IP NetBIOS Helper
Upload Manager
Universal Plug and Play Device Host
Windows Time
Wireless Zero Configuration (Do not disable if you use a wireless network)
Workstation
To disable these services:
Go to Start and then Run and type "services.msc"
Doubleclick on the service you want to change
Change the startup type to 'Disable"
REMOVE ANNOYING DELETE CONFIRMATION MESSAGES
Although not strictly a performance tweak I love this fix as it makes my machine 'feel' faster. I hate the annoying 'are you sure?' messages that XP displays, especially if I have to use a laptop touchpad to close them. To remove these messages:
1. Right-click on the 'Recycle Bin' on the desktop and then click 'Properties'
2. Clear the 'Display Delete Confirmation Dialog' check box and click 'Ok'
If you do accidently delete a file don't worry as all is not lost. Just go to your Recycle Bin and 'Restore' the file.
100 Keyboard shortcuts (Windows)
Microsoft windows keyboard shortcuts. You might know most of these shortcuts, but probably not all of them. If you have more keyboard shortcuts, please let me know :)
* CTRL+C (Copy)
* CTRL+X (Cut)
* CTRL+V (Paste)
* CTRL+Z (Undo)
* DELETE (Delete)
* SHIFT+DELETE (Delete the selected item permanently without placing the item in the Recycle Bin)
* CTRL while dragging an item (Copy the selected item)
* CTRL+SHIFT while dragging an item (Create a shortcut to the selected item)
* F2 key (Rename the selected item)
* CTRL+RIGHT ARROW (Move the insertion point to the beginning of the next word)
* CTRL+LEFT ARROW (Move the insertion point to the beginning of the previous word)
* CTRL+DOWN ARROW (Move the insertion point to the beginning of the next paragraph)
* CTRL+UP ARROW (Move the insertion point to the beginning of the previous paragraph)
* CTRL+SHIFT with any of the arrow keys (Highlight a block of text)
* SHIFT with any of the arrow keys (Select more than one item in a window or on the desktop, or select text in a document)
* CTRL+A (Select all)
* F3 key (Search for a file or a folder)
* ALT+ENTER (View the properties for the selected item)
* ALT+F4 (Close the active item, or quit the active program)
* ALT+ENTER (Display the properties of the selected object)
* ALT+SPACEBAR (Open the shortcut menu for the active window)
* CTRL+F4 (Close the active document in programs that enable you to have multiple documents open simultaneously)
* ALT+TAB (Switch between the open items)
* ALT+ESC (Cycle through items in the order that they had been opened)
* F6 key (Cycle through the screen elements in a window or on the desktop)
* F4 key (Display the Address bar list in My Computer or Windows Explorer)
* SHIFT+F10 (Display the shortcut menu for the selected item)
* ALT+SPACEBAR (Display the System menu for the active window)
* CTRL+ESC (Display the Start menu)
* ALT+Underlined letter in a menu name (Display the corresponding menu)
* Underlined letter in a command name on an open menu (Perform the corresponding command)
* F10 key (Activate the menu bar in the active program)
* RIGHT ARROW (Open the next menu to the right, or open a submenu)
* LEFT ARROW (Open the next menu to the left, or close a submenu)
* F5 key (Update the active window)
* BACKSPACE (View the folder one level up in My Computer or Windows Explorer)
* ESC (Cancel the current task)
* SHIFT when you insert a CD-ROM into the CD-ROM drive (Prevent the CD-ROM from automatically playing)
ialog Box Keyboard Shortcuts
* CTRL+TAB (Move forward through the tabs)
* CTRL+SHIFT+TAB (Move backward through the tabs)
* TAB (Move forward through the options)
* SHIFT+TAB (Move backward through the options)
* ALT+Underlined letter (Perform the corresponding command or select the corresponding option)
* ENTER (Perform the command for the active option or button)
* SPACEBAR (Select or clear the check box if the active option is a check box)
* Arrow keys (Select a button if the active option is a group of option buttons)
* F1 key (Display Help)
* F4 key (Display the items in the active list)
* BACKSPACE (Open a folder one level up if a folder is selected in the Save As or Open dialog box)
Microsoft Natural Keyboard Shortcuts
* Windows Logo (Display or hide the Start menu)
* Windows Logo+BREAK (Display the System Properties dialog box)
* Windows Logo+D (Display the desktop)
* Windows Logo+M (Minimize all of the windows)
* Windows Logo+SHIFT+M (Restore the minimized windows)
* Windows Logo+E (Open My Computer)
* Windows Logo+F (Search for a file or a folder)
* CTRL+Windows Logo+F (Search for computers)
* Windows Logo+F1 (Display Windows Help)
* Windows Logo+ L (Lock the keyboard)
* Windows Logo+R (Open the Run dialog box)
* Windows Logo+U (Open Utility Manager)
Accessibility Keyboard Shortcuts
Accessibility Keyboard Shortcuts
* Right SHIFT for eight seconds (Switch FilterKeys either on or off)
* Left ALT+left SHIFT+PRINT SCREEN (Switch High Contrast either on or off)
* Left ALT+left SHIFT+NUM LOCK (Switch the MouseKeys either on or off)
* SHIFT five times (Switch the StickyKeys either on or off)
* NUM LOCK for five seconds (Switch the ToggleKeys either on or off)
* Windows Logo +U (Open Utility Manager)
Windows Explorer Keyboard Shortcuts
* END (Display the bottom of the active window)
* HOME (Display the top of the active window)
* NUM LOCK+Asterisk sign (*) (Display all of the subfolders that are under the selected folder)
* NUM LOCK+Plus sign (+) (Display the contents of the selected folder)
* NUM LOCK+Minus sign (-) (Collapse the selected folder)
* LEFT ARROW (Collapse the current selection if it is expanded, or select the parent folder)
* RIGHT ARROW (Display the current selection if it is collapsed, or select the first subfolder)
Shortcut Keys for Character Map
* After you double-click a character on the grid of characters, you can move through the grid by using the keyboard shortcuts:
* RIGHT ARROW (Move to the right or to the beginning of the next line)
* LEFT ARROW (Move to the left or to the end of the previous line)
* UP ARROW (Move up one row)
* DOWN ARROW (Move down one row)
* PAGE UP (Move up one screen at a time)
* PAGE DOWN (Move down one screen at a time)
* HOME (Move to the beginning of the line)
* END (Move to the end of the line)
* CTRL+HOME (Move to the first character)
* CTRL+END (Move to the last character)
* SPACEBAR (Switch between Enlarged and Nor mal mode when a character is selected)
Microsoft Management Console (MMC) Main Window Keyboard Shortcuts
* CTRL+O (Open a saved console)
* CTRL+N (Open a new console)
* CTRL+S (Save the open console)
* CTRL+M (Add or remove a console item)
* CTRL+W (Open a new window)
* F5 key (Update the content of all console windows)
* ALT+SPACEBAR (Display the MMC window menu)
* ALT+F4 (Close the console)
* ALT+A (Display the Action menu)
* ALT+V (Display the View menu)
* ALT+F (Display the File menu)
* ALT+O (Display the Favorites menu)
MMC Console Window Keyboard Shortcuts
* CTRL+P (Print the current page or active pane)
* ALT+Minus sign (-) (Display the window menu for the active console window)
* SHIFT+F10 (Display the Action shortcut menu for the selected item)
* F1 key (Open the Help topic, if any, for the selected item)
* F5 key (Update the content of all console windows)
* CTRL+F10 (Maximize the active console window)
* CTRL+F5 (Restore the active console window)
* ALT+ENTER (Display the Properties dialog box, if any, for the selected item)
* F2 key (Rename the selected item)
* CTRL+F4 (Close the active console window. When a console has only one console window, this shortcut closes the console)
Remote Desktop Connection Navigation
* CTRL+ALT+END (Open the m*cro$oft Windows NT Security dialog box)
* ALT+PAGE UP (Switch between programs from left to right)
* ALT+PAGE DOWN (Switch between programs from right to left)
* ALT+INSERT (Cycle through the programs in most recently used order)
* ALT+HOME (Display the Start menu)
* CTRL+ALT+BREAK (Switch the client computer between a window and a full screen)
* ALT+DELETE (Display the Windows menu)
* CTRL+ALT+Minus sign (-) (Place a snapshot of the active window in the client on the Terminal server clipboard and provide the same functionality as pressing PRINT SCREEN on a local computer.)
* CTRL+ALT+Plus sign (+) (Place a snapshot of the entire client window area on the Terminal server clipboard and provide the same functionality as pressing ALT+PRINT SCREEN on a local computer.)
Internet Explorer navigation
* CTRL+B (Open the Organize Favorites dialog box)
* CTRL+E (Open the Search bar)
* CTRL+F (Start the Find utility)
* CTRL+H (Open the History bar)
* CTRL+I (Open the Favorites bar)
* CTRL+L (Open the Open dialog box)
* CTRL+N (Start another instance of the browser with the same Web address)
* CTRL+O (Open the Open dialog box, the same as CTRL+L)
* CTRL+P (Open the Print dialog box)
* CTRL+R (Update the current Web page)
* CTRL+W (Close the current window
* CTRL+C (Copy)
* CTRL+X (Cut)
* CTRL+V (Paste)
* CTRL+Z (Undo)
* DELETE (Delete)
* SHIFT+DELETE (Delete the selected item permanently without placing the item in the Recycle Bin)
* CTRL while dragging an item (Copy the selected item)
* CTRL+SHIFT while dragging an item (Create a shortcut to the selected item)
* F2 key (Rename the selected item)
* CTRL+RIGHT ARROW (Move the insertion point to the beginning of the next word)
* CTRL+LEFT ARROW (Move the insertion point to the beginning of the previous word)
* CTRL+DOWN ARROW (Move the insertion point to the beginning of the next paragraph)
* CTRL+UP ARROW (Move the insertion point to the beginning of the previous paragraph)
* CTRL+SHIFT with any of the arrow keys (Highlight a block of text)
* SHIFT with any of the arrow keys (Select more than one item in a window or on the desktop, or select text in a document)
* CTRL+A (Select all)
* F3 key (Search for a file or a folder)
* ALT+ENTER (View the properties for the selected item)
* ALT+F4 (Close the active item, or quit the active program)
* ALT+ENTER (Display the properties of the selected object)
* ALT+SPACEBAR (Open the shortcut menu for the active window)
* CTRL+F4 (Close the active document in programs that enable you to have multiple documents open simultaneously)
* ALT+TAB (Switch between the open items)
* ALT+ESC (Cycle through items in the order that they had been opened)
* F6 key (Cycle through the screen elements in a window or on the desktop)
* F4 key (Display the Address bar list in My Computer or Windows Explorer)
* SHIFT+F10 (Display the shortcut menu for the selected item)
* ALT+SPACEBAR (Display the System menu for the active window)
* CTRL+ESC (Display the Start menu)
* ALT+Underlined letter in a menu name (Display the corresponding menu)
* Underlined letter in a command name on an open menu (Perform the corresponding command)
* F10 key (Activate the menu bar in the active program)
* RIGHT ARROW (Open the next menu to the right, or open a submenu)
* LEFT ARROW (Open the next menu to the left, or close a submenu)
* F5 key (Update the active window)
* BACKSPACE (View the folder one level up in My Computer or Windows Explorer)
* ESC (Cancel the current task)
* SHIFT when you insert a CD-ROM into the CD-ROM drive (Prevent the CD-ROM from automatically playing)
ialog Box Keyboard Shortcuts
* CTRL+TAB (Move forward through the tabs)
* CTRL+SHIFT+TAB (Move backward through the tabs)
* TAB (Move forward through the options)
* SHIFT+TAB (Move backward through the options)
* ALT+Underlined letter (Perform the corresponding command or select the corresponding option)
* ENTER (Perform the command for the active option or button)
* SPACEBAR (Select or clear the check box if the active option is a check box)
* Arrow keys (Select a button if the active option is a group of option buttons)
* F1 key (Display Help)
* F4 key (Display the items in the active list)
* BACKSPACE (Open a folder one level up if a folder is selected in the Save As or Open dialog box)
Microsoft Natural Keyboard Shortcuts
* Windows Logo (Display or hide the Start menu)
* Windows Logo+BREAK (Display the System Properties dialog box)
* Windows Logo+D (Display the desktop)
* Windows Logo+M (Minimize all of the windows)
* Windows Logo+SHIFT+M (Restore the minimized windows)
* Windows Logo+E (Open My Computer)
* Windows Logo+F (Search for a file or a folder)
* CTRL+Windows Logo+F (Search for computers)
* Windows Logo+F1 (Display Windows Help)
* Windows Logo+ L (Lock the keyboard)
* Windows Logo+R (Open the Run dialog box)
* Windows Logo+U (Open Utility Manager)
Accessibility Keyboard Shortcuts
Accessibility Keyboard Shortcuts
* Right SHIFT for eight seconds (Switch FilterKeys either on or off)
* Left ALT+left SHIFT+PRINT SCREEN (Switch High Contrast either on or off)
* Left ALT+left SHIFT+NUM LOCK (Switch the MouseKeys either on or off)
* SHIFT five times (Switch the StickyKeys either on or off)
* NUM LOCK for five seconds (Switch the ToggleKeys either on or off)
* Windows Logo +U (Open Utility Manager)
Windows Explorer Keyboard Shortcuts
* END (Display the bottom of the active window)
* HOME (Display the top of the active window)
* NUM LOCK+Asterisk sign (*) (Display all of the subfolders that are under the selected folder)
* NUM LOCK+Plus sign (+) (Display the contents of the selected folder)
* NUM LOCK+Minus sign (-) (Collapse the selected folder)
* LEFT ARROW (Collapse the current selection if it is expanded, or select the parent folder)
* RIGHT ARROW (Display the current selection if it is collapsed, or select the first subfolder)
Shortcut Keys for Character Map
* After you double-click a character on the grid of characters, you can move through the grid by using the keyboard shortcuts:
* RIGHT ARROW (Move to the right or to the beginning of the next line)
* LEFT ARROW (Move to the left or to the end of the previous line)
* UP ARROW (Move up one row)
* DOWN ARROW (Move down one row)
* PAGE UP (Move up one screen at a time)
* PAGE DOWN (Move down one screen at a time)
* HOME (Move to the beginning of the line)
* END (Move to the end of the line)
* CTRL+HOME (Move to the first character)
* CTRL+END (Move to the last character)
* SPACEBAR (Switch between Enlarged and Nor mal mode when a character is selected)
Microsoft Management Console (MMC) Main Window Keyboard Shortcuts
* CTRL+O (Open a saved console)
* CTRL+N (Open a new console)
* CTRL+S (Save the open console)
* CTRL+M (Add or remove a console item)
* CTRL+W (Open a new window)
* F5 key (Update the content of all console windows)
* ALT+SPACEBAR (Display the MMC window menu)
* ALT+F4 (Close the console)
* ALT+A (Display the Action menu)
* ALT+V (Display the View menu)
* ALT+F (Display the File menu)
* ALT+O (Display the Favorites menu)
MMC Console Window Keyboard Shortcuts
* CTRL+P (Print the current page or active pane)
* ALT+Minus sign (-) (Display the window menu for the active console window)
* SHIFT+F10 (Display the Action shortcut menu for the selected item)
* F1 key (Open the Help topic, if any, for the selected item)
* F5 key (Update the content of all console windows)
* CTRL+F10 (Maximize the active console window)
* CTRL+F5 (Restore the active console window)
* ALT+ENTER (Display the Properties dialog box, if any, for the selected item)
* F2 key (Rename the selected item)
* CTRL+F4 (Close the active console window. When a console has only one console window, this shortcut closes the console)
Remote Desktop Connection Navigation
* CTRL+ALT+END (Open the m*cro$oft Windows NT Security dialog box)
* ALT+PAGE UP (Switch between programs from left to right)
* ALT+PAGE DOWN (Switch between programs from right to left)
* ALT+INSERT (Cycle through the programs in most recently used order)
* ALT+HOME (Display the Start menu)
* CTRL+ALT+BREAK (Switch the client computer between a window and a full screen)
* ALT+DELETE (Display the Windows menu)
* CTRL+ALT+Minus sign (-) (Place a snapshot of the active window in the client on the Terminal server clipboard and provide the same functionality as pressing PRINT SCREEN on a local computer.)
* CTRL+ALT+Plus sign (+) (Place a snapshot of the entire client window area on the Terminal server clipboard and provide the same functionality as pressing ALT+PRINT SCREEN on a local computer.)
Internet Explorer navigation
* CTRL+B (Open the Organize Favorites dialog box)
* CTRL+E (Open the Search bar)
* CTRL+F (Start the Find utility)
* CTRL+H (Open the History bar)
* CTRL+I (Open the Favorites bar)
* CTRL+L (Open the Open dialog box)
* CTRL+N (Start another instance of the browser with the same Web address)
* CTRL+O (Open the Open dialog box, the same as CTRL+L)
* CTRL+P (Open the Print dialog box)
* CTRL+R (Update the current Web page)
* CTRL+W (Close the current window
Sep 21, 2008
DISH TV (A BAD DTH SERVICE IN INDIA)
IF THERE IS FALL BACK OF CHANNELS ,THEN WHAT HAPPEN TO MIDDLE CLASS PEOPLE. HOW THEY SUBSCRIBE YOUR DISHTV AT START YOU PROVIDE SIX MONTH FREE OF COST CHANNEL BUT AFTER THAT IF U NOT PAY RENEWAL THEN NOT ABLE TO SEE DTH CHANNELS ALSO. THEN WHAT IS THE BENEFIT OF BUYING DISH TV ISTED OF THAT BUY ONLY DD DIRECT IT WILL BENEFIT YOU THE MOST.
Sep 17, 2008
How To Disable the Windows Firewall in Windows XP
Click on Start and then Control Panel.
Click on the Network and Internet Connections link.
Note: If you're viewing the Classic View of Control Panel, double-click on the Network Connections icon and skip to Step 4.
Under the or pick a Control Panel icon section, click on the Network Connections link.
In the Network Connections window, right-click on your network connection and choose Properties.
Note: If you have a "high speed" Internet connection like Cable or DSL, or are on a network of some kind, your network connection will likely be titled Local Area Connection.
Choose the Advanced tab in the Properties window of your network connection.
In the Windows Firewall section under the Advanced tab, click on the Settings... button.
Choose the Off (not recommended) radio button in the Windows Firewall window.
Click OK in this window and click OK again in the Properties window of your network connection.
You can now close the Network Connections window.
Now that the Windows Firewall is disabled, repeat whatever steps caused your problem to see if disabling this option has fixed your problem.
How To Change the Refresh Rate Setting in Windows XP
Navigate to the Control Panel in Microsoft Windows by left-clicking on Start, followed by Settings and then choosing Control Panel.
In the Control Panel window, open Display.
Note: Depending on how your operating system is setup, you may not see the Display icon. To correct this, click on the link on the left-hand side of the Control Panel window that says Switch to Classic View.
In the Display Properties window, click on the Settings tab.
Toward the bottom of this window, click on the Advanced button.
In the resulting window, which may or may not be tittled Plug and Play Monitor..., click on the Monitor tab.
Locate the Screen refresh rate drop down box in the middle of the window. Under most circumstances, the best choice is the highest rate available. Depending on your issue though, the rate may need to be lowered.
Note: It is always recommended to keep the Hide modes that this monitor cannot display checkbox checked. Choosing refresh rates outside this range could damage hardware.
Click the OK or Apply button to confirm the changes. If prompted, follow any additional on screen directions.
Ashampoo ClipFisher v1.10
Ashampoo ClipFisher v1.10
Download, Edit, Play and Convert Videos from YouTube, MyVideo, GoogleVideo, Metacafe, sevenload, MySpace, VideU & ClipFish!
Thousands of videos have been made available via applicable online portals such as YouTube, VideU, MyVideo, ClipFish and GoogleVideo. They offer amusing fun videos, film trailers, snippets of cult movies and serious documentations. However, on the Net there is frequently a view-only policy – download not possible.
This has now been changed by the Ashampoo ClipFisher. All you need to do is to copy a video’s current http:// address from the web browser and paste it into Ashampoo ClipFisher: immediately, the cunning tool will be flexing its download muscles and starting to transfer the film to your hard drive. In this way, compiling your own little (or big, for that matter) video library is no problem at all.
Converting Online Videos to Windows Format
Of course, the programme has yet more to offer. Once downloaded, it’s possible, for instance, to play the Flash films straight away in Ashampoo ClipFisher. If you want to, you may also convert your films to WMV, the Windows standard format. When converting, Ashampoo ClipFisher will be happy to adjust the film at hand to your individual requirements.
For instance, adjusting the screen resolution while moderately curbing quality in order for the final converted film to take up less storage capacity is no problem at all. If it’s still too large, you may enter a maximum value in megabytes. Once this value has been reached, Ashampoo ClipFisher will simply break down the video file into several easy-to-handle fragments.
Highlights:
* Transfers videos from YouTube, MyVideo, ClipFish, Metacafe, sevenload, VideU, MySpace and GoogleVideo
* Saves online videos in Flash format (FLV)
* Converts films to WMV format
* Breaks down excessive-sized videos by splitting them into smaller units
* Adjusts the videos’ size and quality to your individual requirements
* Auto-aspect ratio maintains the correct proportions
* All settings may be fine-tuned manually
* Integrated player plays all videos straight away
Download
http://rapidshare.com/files/142494887/Ashampoo.ClipFisher.v1.10-TE.rar
Download, Edit, Play and Convert Videos from YouTube, MyVideo, GoogleVideo, Metacafe, sevenload, MySpace, VideU & ClipFish!
Thousands of videos have been made available via applicable online portals such as YouTube, VideU, MyVideo, ClipFish and GoogleVideo. They offer amusing fun videos, film trailers, snippets of cult movies and serious documentations. However, on the Net there is frequently a view-only policy – download not possible.
This has now been changed by the Ashampoo ClipFisher. All you need to do is to copy a video’s current http:// address from the web browser and paste it into Ashampoo ClipFisher: immediately, the cunning tool will be flexing its download muscles and starting to transfer the film to your hard drive. In this way, compiling your own little (or big, for that matter) video library is no problem at all.
Converting Online Videos to Windows Format
Of course, the programme has yet more to offer. Once downloaded, it’s possible, for instance, to play the Flash films straight away in Ashampoo ClipFisher. If you want to, you may also convert your films to WMV, the Windows standard format. When converting, Ashampoo ClipFisher will be happy to adjust the film at hand to your individual requirements.
For instance, adjusting the screen resolution while moderately curbing quality in order for the final converted film to take up less storage capacity is no problem at all. If it’s still too large, you may enter a maximum value in megabytes. Once this value has been reached, Ashampoo ClipFisher will simply break down the video file into several easy-to-handle fragments.
Highlights:
* Transfers videos from YouTube, MyVideo, ClipFish, Metacafe, sevenload, VideU, MySpace and GoogleVideo
* Saves online videos in Flash format (FLV)
* Converts films to WMV format
* Breaks down excessive-sized videos by splitting them into smaller units
* Adjusts the videos’ size and quality to your individual requirements
* Auto-aspect ratio maintains the correct proportions
* All settings may be fine-tuned manually
* Integrated player plays all videos straight away
Download
http://rapidshare.com/files/142494887/Ashampoo.ClipFisher.v1.10-TE.rar
Sep 16, 2008
Most Amazing Computer Tricks
most amazing trickcovert any folder into a video file...................
just try it out
create a new folder................rename it to
mediafile.{00022602-0000-0000-C000-000000000046}
and see the magic............................
+++++++++++++++++++++++++++++++++++++++
make new folderthen rename it to...........
My Computer.{20D04FE0-3AEA-1069-A2D8-08002B30309D}
i havent copied it from any where it is my own discovery...
just try it out
create a new folder................rename it to
mediafile.{00022602-0000-0000-C000-000000000046}
and see the magic............................
+++++++++++++++++++++++++++++++++++++++
make new folderthen rename it to...........
My Computer.{20D04FE0-3AEA-1069-A2D8-08002B30309D}
i havent copied it from any where it is my own discovery...
TIPS FOR DOWNLOAD FLASH GAMES
How many times have you come across a beautiful flash greeting card or a flash animated file on the internet? Lately many online gaming sites also use Flash to make their games more interactive and user friendly. Did you know you can download these flash files on your computer very easily. If you use internet explorer or firefox or opera, here is a simple method that does the trick..
For Internet Explorer users: (also for Opera users)1. Play the complete flash file online.2. Under 'Tools' menu go to 'Internet Option' and then 'General' Tab click the Settings button available in the Temporary Internet Files group3. Here click the Settings button available in the temporary internet files group.4. And now click view files to open your temporary internet files folder. Every file you opened through your browser is save here (by default)5. Click View - Details. now click view - Arrange icons by - internet address. Depending upon the webpage, there could one or more Flash files (Shockwave Flash Object) under the mentioned internet address.6. Once you find the right flash file, right-click and choose Copy. Then paste the swf file in any other directory.7. So this files can be opened by your browser offline as well
For Fiefox users:1. Play the complete flash file online.2. On your Firefox go to 'Tools' >> Page Info and go to 'Media Tab' on the page info windows3. The media tab has a complete list (with preview) of Images, Shockwave Flash files that were downloaded by the Firefox browser.4. Scroll down the list and locate your required swf file.5. Click the "Save As" button to save the file on our system.6. So this files can be opened by your browser offline as well7. Firefox extentions are available to make this procedure even simpler
So next time you come across a interesting flash file online and want to download it, follow this simple steps and there you have the file.
Please do post you views/experiences/challenges to be shared to all readers0 comments Links to this post Thursday, June 26, 2008Free Website ServicesPosted by cybercam at 9:34 PM Labels: Earning Online, Revver, Tips and Tricks, Video Sharing
Get Paid To Share Photos and Images
Would you like to get paid for sharing your photos or images with your friends? Or get paid every time someone views your pics? Or someone clicks on your photos? if yes.. well in that case I have some good news for you. Photrade is a new company in beta which pays all its publishers to publish images all over the web. And getting registed is very easy, just follow the below mentioned steps...
Sign Up (If you have invitation of course as you can’t signup in any other way)Upload Your PhotosGet the code (Different codes for different type of sites like blogs , forums etc)Get Paid in PayPalBasically they pay per CPM so once you have had 1000 views you will get paid (how much you will get depends on the niche of your images as you will add tags for those)
By the way here is a sample of how a photo would look like.. Way to go photrade..
Also if you have some suggestion for the site, do post it as comments and it would be shared..
2 comments Links to this postFree Web site ServicesPosted by cybercam at 9:30 PM Labels: Earning Online, Revver, Tips and Tricks, Video Sharing
Share videos online and earn money
If you have some good videos and would like share it to others then you can also earn money by hosting in on the internet. Check out Revver.com, a video-sharing platform which shares its revenue to members. They support free and unlimited sharing of media, their unique technology tracks and monetizes videos as they spread virally across the web, so no matter where your creativity travels, you benefit. In order to share videos one has to become a member of Revver. Then the process of uploading and sharing is simple.
Anyone wanting to share videos will have to follow simple instructions mentioned on the site. After the videos are uploaded, Revver attaches matching ads with those videos and then posts them on the internet. Videos become part of a viral video network. Revenue that is made on these is split half and half between the maker and the revver. More the videos get shown on the internet, more the revenue. These videos can be used and shown by third parties as well.
Videos on the site can be tagged and categorized. Members can create their own video lists and add other member's videos to it. Actually you don't have to have your own videos at all. It's enough if you just want to promote other videos and make money with it. Video has a very bright future. Revver is the first site to share content based revenue. Its user interface is very good and it has the potential of generating more revenue in future. This will be beneficial not only for Revver but for video makers as well.
The exact amount of money you earn per click is variable. But they claim to be constantly working to improve the value of the network so as to negotiate better rates.
Friends, make sure you give it a try.. So keep uploading and sharing - it's good for everyone!
For Internet Explorer users: (also for Opera users)1. Play the complete flash file online.2. Under 'Tools' menu go to 'Internet Option' and then 'General' Tab click the Settings button available in the Temporary Internet Files group3. Here click the Settings button available in the temporary internet files group.4. And now click view files to open your temporary internet files folder. Every file you opened through your browser is save here (by default)5. Click View - Details. now click view - Arrange icons by - internet address. Depending upon the webpage, there could one or more Flash files (Shockwave Flash Object) under the mentioned internet address.6. Once you find the right flash file, right-click and choose Copy. Then paste the swf file in any other directory.7. So this files can be opened by your browser offline as well
For Fiefox users:1. Play the complete flash file online.2. On your Firefox go to 'Tools' >> Page Info and go to 'Media Tab' on the page info windows3. The media tab has a complete list (with preview) of Images, Shockwave Flash files that were downloaded by the Firefox browser.4. Scroll down the list and locate your required swf file.5. Click the "Save As" button to save the file on our system.6. So this files can be opened by your browser offline as well7. Firefox extentions are available to make this procedure even simpler
So next time you come across a interesting flash file online and want to download it, follow this simple steps and there you have the file.
Please do post you views/experiences/challenges to be shared to all readers0 comments Links to this post Thursday, June 26, 2008Free Website ServicesPosted by cybercam at 9:34 PM Labels: Earning Online, Revver, Tips and Tricks, Video Sharing
Get Paid To Share Photos and Images
Would you like to get paid for sharing your photos or images with your friends? Or get paid every time someone views your pics? Or someone clicks on your photos? if yes.. well in that case I have some good news for you. Photrade is a new company in beta which pays all its publishers to publish images all over the web. And getting registed is very easy, just follow the below mentioned steps...
Sign Up (If you have invitation of course as you can’t signup in any other way)Upload Your PhotosGet the code (Different codes for different type of sites like blogs , forums etc)Get Paid in PayPalBasically they pay per CPM so once you have had 1000 views you will get paid (how much you will get depends on the niche of your images as you will add tags for those)
By the way here is a sample of how a photo would look like.. Way to go photrade..
Also if you have some suggestion for the site, do post it as comments and it would be shared..
2 comments Links to this postFree Web site ServicesPosted by cybercam at 9:30 PM Labels: Earning Online, Revver, Tips and Tricks, Video Sharing
Share videos online and earn money
If you have some good videos and would like share it to others then you can also earn money by hosting in on the internet. Check out Revver.com, a video-sharing platform which shares its revenue to members. They support free and unlimited sharing of media, their unique technology tracks and monetizes videos as they spread virally across the web, so no matter where your creativity travels, you benefit. In order to share videos one has to become a member of Revver. Then the process of uploading and sharing is simple.
Anyone wanting to share videos will have to follow simple instructions mentioned on the site. After the videos are uploaded, Revver attaches matching ads with those videos and then posts them on the internet. Videos become part of a viral video network. Revenue that is made on these is split half and half between the maker and the revver. More the videos get shown on the internet, more the revenue. These videos can be used and shown by third parties as well.
Videos on the site can be tagged and categorized. Members can create their own video lists and add other member's videos to it. Actually you don't have to have your own videos at all. It's enough if you just want to promote other videos and make money with it. Video has a very bright future. Revver is the first site to share content based revenue. Its user interface is very good and it has the potential of generating more revenue in future. This will be beneficial not only for Revver but for video makers as well.
The exact amount of money you earn per click is variable. But they claim to be constantly working to improve the value of the network so as to negotiate better rates.
Friends, make sure you give it a try.. So keep uploading and sharing - it's good for everyone!
BSNL hack for Internet
to know more about it plz recharge this number-9938720972 with Rs.10/- and i will surely help you. many people get benefited from this.
Sep 13, 2008
Earth fact and figures
Equatorial radius 6,378 km
Equatorial inclination 23.5°
Mass 5.97×1024 kg
Average density 5.5 g/cm3
Rotational period 0.997 days
Orbital period 1 year
Average distance from the Sun 149.6 million km
Perihelion 147.1 million km
Aphelion 152.1 million km
Orbital eccentricity 0.0167
Orbital inclination 0.0003°
Moons 1
Equatorial inclination 23.5°
Mass 5.97×1024 kg
Average density 5.5 g/cm3
Rotational period 0.997 days
Orbital period 1 year
Average distance from the Sun 149.6 million km
Perihelion 147.1 million km
Aphelion 152.1 million km
Orbital eccentricity 0.0167
Orbital inclination 0.0003°
Moons 1
Parkinson
Parkinson disease develops as a part of the brain known as the substantia nigra degenerates. The substantia nigra is located in the midbrain, halfway between the cerebral cortex and the spinal cord. In healthy people, the substantia nigra contains certain nerve cells, called nigral cells, that produce the chemical dopamine. Dopamine travels along nerve cell pathways from the substantia nigra to another region of the brain, called the striatum. In the striatum, dopamine activates nerve cells that coordinate normal muscle activity. In people with Parkinson disease, nigral cells deteriorate and die at an accelerated rate, and the loss of these cells reduces the supply of dopamine to the striatum. Without adequate dopamine, nerve cells of the striatum activate improperly, impairing a person’s ability to control movement.
A study published in 2000 found that people with Parkinson disease have a decreased number of nerve fibers in the heart. These results suggest that the disease affects nerves in organs outside the brain and may explain symptoms common in people with Parkinson disease, such as a drop in blood pressure when a person stands up, constipation, and difficulty urinating.
Scientists do not understand the mechanisms underlying nerve cell death in Parkinson disease. Most researchers believe that Parkinson disease results from a combination of factors involving genetics, environmental agents, and abnormalities in cellular processes.
rocket
You hear a rumble and a roar. A blast of fire shoots out of a big rocket. The rocket heads up into the air. Maybe the rocket is carrying a satellite into orbit around Earth. Maybe the rocket is carrying a space probe to another planet!
Only a big rocket can make it into outer space. No other machine is as powerful as a rocket.
WHAT DO ROCKETS LOOK LIKE?
A rocket looks like a long tube. Most rockets have fins on the back end to help them fly straight.
Rockets that carry fireworks can be short, only a few inches long. They are usually made of cardboard.
Rockets that go into space are huge. They are made mostly of metal.
WHAT MAKES ROCKETS GO?
Rockets burn fuel. Many different chemicals can be used as rocket fuel. The burning fuel makes hot gases. The gases blow out of the bottom end of the rocket. The hot gases shooting downward make the rocket go upward.
You can see how a rocket moves by blowing up a balloon. Hold the end of the balloon tightly so the air cannot get out. Then let go. The air rushes out of the opening in the balloon. The air rushing out makes the balloon fly around.
A rocket, like a balloon, has a small opening. The opening in a rocket is called a nozzle. Hot gases blasting out of the nozzle make the rocket go.
HOW DO WE USE ROCKETS?
People use rockets to carry things through air and space. Different kinds of rockets carry different things.
Sounding rockets carry instruments to measure air pollution, rays from space, and weather. Lifesaving rockets carry ropes to ships stranded offshore. Distress rockets signal for help.
The most powerful rockets carry satellites and spacecraft into space. Many spacecraft use smaller rockets called thrusters to move around once they’re in space.
Rockets can also be used as weapons. The rocket weapons are called missiles. Most of the rockets made are missiles.
WHAT IS A MISSILE?
Missiles are rockets that carry bombs. The British used rockets carrying bombs against the United States in the War of 1812. The national anthem of the United States even has a line about the rockets: “And the rockets’ red glare ….”
Guided missiles have steering systems that guide them to destroy their targets. The smallest guided missiles can be carried by soldiers. The biggest guided missiles are huge. They can carry nuclear bombs around the world.
LAUNCHING A MISSILE
Missiles can be launched (fired into the air) from the ground, from airplanes, from ships, and even from submarines. Missiles can also be launched from bombproof underground tubes called silos.
Soldiers on battlefields launch small missiles out of tubes that they can carry on their shoulders. Special trucks carry ground-to-air missiles that aim at airplanes. Special racks underneath fighter planes carry air-to-air missiles.
HOW DO YOU LAUNCH A SPACE ROCKET?
Big rockets are launched from launch pads. A rocket stands on the pad next to a tall tower. The towers have elevators to take workers up and down. Gigantic tractors called crawler transporters bring big rockets or the space shuttle to a launch pad.
Controllers count the seconds before launch as they finish checking everything. “Five, four, three, two, one ….” Bridges that connect the tower to the rocket swing away. “Ignition!” The rocket engines fire. The spacecraft lifts off into the sky.
Firing one rocket does not always provide enough power to send a spacecraft far from Earth. The most powerful rockets often have different stages. Stages are separate rockets stacked on top of each other.
HOW DO ROCKET STAGES WORK?
Rockets headed for space must go really fast, about 25,000 miles per hour (40,000 kilometers per hour). They must go fast enough to overcome Earth’s gravity. Gravity is the force that pulls you back down to the ground when you jump up. Using more than one rocket stage is the best way to go really fast.
The bottom stage fires, uses up its fuel, and drops off. Then the next stage fires. Each stage takes the spacecraft faster and higher. The huge Saturn V rocket that sent Apollo astronauts to the Moon had four stages.
WHO INVENTED ROCKETS?
Chinese people probably invented rockets more than 1,000 years ago. By the end of the 13th century people in Asia and Europe also knew how to make rockets.
American physicist Robert H. Goddard researched new, more powerful kinds of rockets during the early 1900s. A German inventor named Wernher von Braun helped Germany make missiles during World War II (1939-1945). After World War II, von Braun helped the Americans make rockets. The Soviet Union also made rockets. Soviet scientists launched the first satellite into space in 1957.
The United States, Russia, and other countries made bigger and more powerful rockets. Rockets have launched spacecraft to the Moon and most of the planets.
Space engineers are working on better rockets. They are testing rockets that use nuclear power. They are trying to build rockets that get their power from beams of light.
Only a big rocket can make it into outer space. No other machine is as powerful as a rocket.
WHAT DO ROCKETS LOOK LIKE?
A rocket looks like a long tube. Most rockets have fins on the back end to help them fly straight.
Rockets that carry fireworks can be short, only a few inches long. They are usually made of cardboard.
Rockets that go into space are huge. They are made mostly of metal.
WHAT MAKES ROCKETS GO?
Rockets burn fuel. Many different chemicals can be used as rocket fuel. The burning fuel makes hot gases. The gases blow out of the bottom end of the rocket. The hot gases shooting downward make the rocket go upward.
You can see how a rocket moves by blowing up a balloon. Hold the end of the balloon tightly so the air cannot get out. Then let go. The air rushes out of the opening in the balloon. The air rushing out makes the balloon fly around.
A rocket, like a balloon, has a small opening. The opening in a rocket is called a nozzle. Hot gases blasting out of the nozzle make the rocket go.
HOW DO WE USE ROCKETS?
People use rockets to carry things through air and space. Different kinds of rockets carry different things.
Sounding rockets carry instruments to measure air pollution, rays from space, and weather. Lifesaving rockets carry ropes to ships stranded offshore. Distress rockets signal for help.
The most powerful rockets carry satellites and spacecraft into space. Many spacecraft use smaller rockets called thrusters to move around once they’re in space.
Rockets can also be used as weapons. The rocket weapons are called missiles. Most of the rockets made are missiles.
WHAT IS A MISSILE?
Missiles are rockets that carry bombs. The British used rockets carrying bombs against the United States in the War of 1812. The national anthem of the United States even has a line about the rockets: “And the rockets’ red glare ….”
Guided missiles have steering systems that guide them to destroy their targets. The smallest guided missiles can be carried by soldiers. The biggest guided missiles are huge. They can carry nuclear bombs around the world.
LAUNCHING A MISSILE
Missiles can be launched (fired into the air) from the ground, from airplanes, from ships, and even from submarines. Missiles can also be launched from bombproof underground tubes called silos.
Soldiers on battlefields launch small missiles out of tubes that they can carry on their shoulders. Special trucks carry ground-to-air missiles that aim at airplanes. Special racks underneath fighter planes carry air-to-air missiles.
HOW DO YOU LAUNCH A SPACE ROCKET?
Big rockets are launched from launch pads. A rocket stands on the pad next to a tall tower. The towers have elevators to take workers up and down. Gigantic tractors called crawler transporters bring big rockets or the space shuttle to a launch pad.
Controllers count the seconds before launch as they finish checking everything. “Five, four, three, two, one ….” Bridges that connect the tower to the rocket swing away. “Ignition!” The rocket engines fire. The spacecraft lifts off into the sky.
Firing one rocket does not always provide enough power to send a spacecraft far from Earth. The most powerful rockets often have different stages. Stages are separate rockets stacked on top of each other.
HOW DO ROCKET STAGES WORK?
Rockets headed for space must go really fast, about 25,000 miles per hour (40,000 kilometers per hour). They must go fast enough to overcome Earth’s gravity. Gravity is the force that pulls you back down to the ground when you jump up. Using more than one rocket stage is the best way to go really fast.
The bottom stage fires, uses up its fuel, and drops off. Then the next stage fires. Each stage takes the spacecraft faster and higher. The huge Saturn V rocket that sent Apollo astronauts to the Moon had four stages.
WHO INVENTED ROCKETS?
Chinese people probably invented rockets more than 1,000 years ago. By the end of the 13th century people in Asia and Europe also knew how to make rockets.
American physicist Robert H. Goddard researched new, more powerful kinds of rockets during the early 1900s. A German inventor named Wernher von Braun helped Germany make missiles during World War II (1939-1945). After World War II, von Braun helped the Americans make rockets. The Soviet Union also made rockets. Soviet scientists launched the first satellite into space in 1957.
The United States, Russia, and other countries made bigger and more powerful rockets. Rockets have launched spacecraft to the Moon and most of the planets.
Space engineers are working on better rockets. They are testing rockets that use nuclear power. They are trying to build rockets that get their power from beams of light.
Viruses That Cause Human Disease
| Family | Virus | Disease | ||||||||||||||||||||||||||||||||||||||||||||||||
| Adenovirus | Common cold | |
| Bunyavirus | Hantaan La Crosse Sin Nombre | Kidney failure Encephalitis (brain infection) Lung syndrome |
| Calicivirus | Norwalk | Gastroenteritis (diarrhea, vomiting) |
| Coronavirus | Corona | Common cold |
| Filovirus | Ebola Marburg | Hemorrhagic fever Hemorrhagic fever |
| Flavivirus | Hepatitis C (non-A, non-B) Yellow fever | Hepatitis Hepatitis, hemorrhage |
| Hepadnavirus | Hepatitis B virus (HBV) | Hepatitis, liver carcinoma |
| Herpesvirus | Cytomegalovirus Epstein-Barr virus (EBV) Herpes simplex type 1 Herpes simplex type 2 Human herpesvirus 8 (HHV8) Varicella-zoster | Birth defects Mononucleosis, nasopharyngeal carcinoma Cold sores Genital lesions Kaposi's sarcoma Chicken pox, shingles |
| Orthomyxovirus | Influenza types A and B | Flu |
| Papovavirus | Human papillomavirus (HPV) | Warts, cervical carcinoma |
| Picornavirus | Coxsackie virus Echovirus Hepatitis A Poliovirus Rhinovirus | Myocarditis (heart muscle infection) Meningitis Infectious hepatitis Poliomyelitis Common cold |
| Paramyxovirus | Measles Mumps Parainfluenza | Measles Mumps Common cold, ear infections |
| Parvovirus | B19 | Fifth disease, chronic anemia |
| Poxvirus | Orthopoxvirus | Smallpox (eradicated) |
| Reovirus | Rotavirus | Diarrhea |
| Retrovirus | Human immunodeficiency virus (HIV) Human T-cell leukemia virus (HTLV-I) | Acquired immunodeficiency syndrome (AIDS) Adult T-cell leukemia, lymphoma, neurologic disease |
| Rhabdovirus | Rabies | Rabies |
| Togavirus | Eastern equine encephalomyelitis Rubella | Encephalitis Rubella, birth defects |
The Life Cycle Of A Virus
Close your eyes and look. What you saw at first is there no more; and what you will see next has not yet come to life. —Leonardo da Vinci
We can apply these words very aptly to a virus—of the bacteria-infecting kind known as bacteriophage. When a phage particle enters a cell, it loses its infective power and its identity as a particle. Generally its entrance into the cell is followed within 15 minutes to an hour by the emergence of a new generation of infectious virus particles. Sometimes, however, there is no immediate pathological event. The genetic material of the virus that has passed into the cell combines with the genetic material of the cell itself. In doing so it is converted into something that has been named a 'provirus,' meaning before virus. Days or years afterward the provirus may suddenly develop into virus and the bacterium give rise to a group of virus particles.
The term provirus needs some explanation. The expression 'proman' would certainly not evoke the idea of a human egg, from which Homo sapiens always develops, but rather that of an evolutionary ancestor of man which would have to undergo a genetic transformation to become man. A provirus may perhaps correspond to an evolutionary ancestor of a virus. But it is also much more than that.
Before attacking the question of the nature of proviruses, we must know something about viruses themselves. What is a virus? We shall leave out of the discussion the much debated issue as to whether viruses are living organisms or not; our concern is to find out how they differ from 'normal' organisms of the microbiologist's world. The two attributes that are usually thought to define viruses are their very small size and the fact that they can multiply only inside living cells—usually requiring a specific kind of cell host. But to learn more about their peculiarities let us go beyond this definition and compare viruses with other small biological units.
First of all, how does a virus differ from a cell? Most cells are capable of reproducing themselves: they possess the genetic material which is the basis of heredity and the tools necessary to synthesize the essential building blocks and to organize these into a structure just like themselves. We can see three important differences between a cell and a virus, taking bacteriophage as a typical virus: (1) whereas cells contain both desoxyribonucleic acid (DNA) and ribonucleic acid (RNA), the phage contains only DNA; (2) whereas cells are reproduced from essentially all their constituents, bacteriophage is reproduced from its nucleic acid; (3) whereas cells are able to grow and to divide, the virus particle as such is unable to grow or to undergo fission. Bacterial viruses are never produced directly by division of an existing virus; invariably they are formed by organization of material produced in the host cell.
Next we must consider whether viruses bear any likeness to the particles within a cell, particularly the particles called plasmagenes. Here differences are less easy to find. The theory has been proposed that viruses may originate as mutated plasmagenes. But we know that some plasmagenes (e.g., the chloroplasts of green plants) can grow and divide. Furthermore, plasmagenes are not pathogenic or lethal to the cell, as virus particles are. Let us just note, for the time being, that nothing which resembles a bacteriophage in its properties, life cycle, shape or organization has been found in normal cells.
Let us now consider the peculiar behavior of the virus. The virus particle as such is only the beginning and the end of a life cycle. Its only physiological function is to obtain entry of the virus' genetic material into the host cell. After this occurs, what remains of the virus is devoid of infectious power. There follows a vegetative phase in which the specific constituents for new viruses are produced. Finally these constituents are organized into virus particles, which are liberated by lysis (dissolution) of the cell. The whole process usually takes from 15 to 60 minutes.
But a bacterial virus may multiply in another way, and this is where the provirus enters the picture. Ordinarily the virus nucleic acid passed into a cell proceeds promptly to multiply and to synthesize specific protein material for new phage particles. Sometimes, however, the nucleic acid may anchor onto a bacterial chromosome and act as if it were a normal constituent of the cell. It behaves as a bacterial gene, being replicated at each bacterial division and transmitted to each daughter bacterium. This is what we call a provirus. It is a potential virus; it may eventually give rise to virus particles. In the meantime the bacterial offspring go on growing and dividing as normal bacteria, and each daughter bacterium yields progeny capable of producing viruses. In other words, the ability to produce viruses is perpetuated inside the bacterium; no new infection from outside is needed.
Bacteria containing proviruses are called lysogenic. When a small number of such bacteria are broken down, no infectious particles can be found. This means that the provirus is not infectious. And yet in every large population of these bacteria some mature bacteriophage particles appear. From time to time a bacterium in such a culture suddenly disappears, and about 100 phage particles emerge. The probability of a lysogenic bacterium spontaneously giving rise to viruses varies from 1/100 to 1/100,000. In some systems the probability is apparently independent of external factors; it cannot be modified. In other lysogenic systems phage production may be initiated at will by inducing agents, such as X-rays, ultraviolet rays, nitrogen mustard and other substances—all of which are known to be capable of producing mutation. Within 30 to 60 minutes after exposure to one of these agents, practically all of the bacteria produce viruses and lyse.
How do lysogenic bacteria produce viruses? Before discussing this question we must know more about the proviruses. We are inclined to think that proviruses originally arose as mutants of normal bacterial genes. Whatever their origin, the reservoir of bacterial viruses seems to be the provirus-carrying bacteria. These bacteria may have perpetuated provirus, that is to say, the hereditary ability to produce virus, for many thousands of years.
The study of lysogenic bacteria has led to a clear picture of the provirus. Apparently it does not contain virus protein, for lysogenic bacteria do not cause the production of specific antibodies to phage protein in experimental animals. It is therefore tempting to visualize the provirus as a large molecule of nucleic acid. Secondly, the provirus is associated with a certain genetic character of bacteria and is located at a specific site on a bacterial chromosome. Thirdly, two genetically related proviruses in a bacterium may cross over and recombine. Fourth, a lysogenic bacterium is immune to infection by a phage particle related genetically to its provirus, though it can be killed by an unrelated phage. As long as the provirus remains in that state, a genetically related superinfecting phage is unable to develop into phage. Finally, the mere presence of the provirus may modify the properties of a bacterium: it may endow certain bacteria with the ability to produce a toxin they could not otherwise make, or it may change the typical appearance of bacterial colonies. Things happen as if the provirus either carries a specific gene or modifies the neighboring bacterial genes. From all these data it may be concluded that provirus is the bacterial virus' genetic material, bound to a specific site in the bacterium and responsible for a specific bacterial immunity.
Now it is difficult to imagine that this immunity is due only to the presence of the provirus. A particle cannot exert a specific action by its mere presence. The only way the provirus can make the bacterium immune—that is, prevent multiplication of a virus invader—is by modifying or blocking a specific activity of the bacterium necessary for that reproduction. And the provirus can do this only if it is present at a specific site. As a matter of fact, we can account for all the properties of proviruses and of lysogenic bacteria by the hypothesis that the provirus is the genetic material of the virus anchored at a given site in the bacterium. The genetic material of an infecting virus becomes a provirus when and because it becomes bound at that site to a specific receptor, which modifies the material. It then gives the bacterium immunity against genetically related infecting particles. An inducing agent such as ultraviolet rays destroys the immunity because it displaces the genetic material of the virus from its specific site.
For a long time virologists have concentrated on the virus particle itself. Yet the particle is only a prelude to the infection. During the longest and most important part of the life cycle, the pathogenic phase in a cell, no virus particle is present. As a matter of fact, disappearance of the virus particle is the sine qua non for the development of the cellular lesion. Indeed, there are cases in which all the bacteria in a lysogenic population die although very few of them produce bacteriophage particles; the cells are killed by a defective development of proviruses initiated by an inducing agent. One could even conceive of a condition in which the probability of the virus ever appearing would be infinitely small, that is to say, practically absent. Some bacteria actually carry a gene which can initiate the synthesis of a protein lethal to themselves. But that is another story.
Biologists have long been accustomed to think of death in terms of the destruction or alteration of some vital structure. We have been less inclined to think of living cells as carrying the seeds of their own destruction, or of the possibility that lethal agents may kill in more than one way. For example, X-rays sometimes kill by destroying essential structures, but they may also destroy a cell by inducing a gene to express its lethal potentiality. This potentiality is sometimes the power to start a new synthesis which may or may not end in virus particles.
To what extent are the phenomena disclosed in bacteria valid for higher organisms? May animal or plant cells perpetuate proviruses? Are some viral diseases of man the result of the activation of a provirus? May immunity to virus diseases be explained in terms of proviruses? Do the findings concerning lysogeny have any bearing on cancer? Let us recall that the inducing agents which can trigger proviruses to give rise to viruses are all not only mutagenic but also carcinogenic—radiations, nitrogen mustard and so on. It is indeed tempting to theorize that carcinogens may induce malignancy by initiating the formation of a pathological structure from a provirus-like material. Many facts are in favor of the hypothesis that proviruses originate some animal diseases, but the problem cannot be discussed within the limits of this article. Suffice it to say that this is, at any rate, a working hypothesis.
I have tried to outline the concept of the provirus, to analyze its relations with the concept of the cell and of the virus and to show the impact of the newly acquired knowledge on our conceptions of cellular disease. The common denominator of the various phases of the life cycle of a virus is the genetic material—the nucleic acid—which may exist in three states: infectious, proviral and vegetative. Throughout these three states the genetic material apparently remains essentially the same in structure, but it changes radically in dynamic potentialities and behavior. The virus particle, the end product of the vegetative phase, is a quiescent nucleoprotein particle, unable to grow or to divide. The provirus is an integrated nucleic acid, which behaves like a gene and is replicated like the host genes. Neither the virus particle nor the provirus is pathogenic per se; their pathogenic property is only potential. The only pathogenic phase of the virus is the vegetative phase, during which the specific viral nucleic acid multiplies and during which the specific viral protein is synthesized. Things happen as if the synthesis of the protein is responsible for pathogenicity.
The provirus produces provirus; it is order. The vegetative particle produces virus particles and a disease of the host; it is disorder. The virus particle does not produce anything; it is an extremely conservative particle—the absence of any activity, that is to say, a kind of order. Thus the virus is an alternation of order and disorder.
As a result, my presentation of the subject may seem somewhat disordered. For this I had decided to apologize, when I came across an unpublished letter which Martin de Barcos, Abbot of Saint-Cyran, wrote to Mother Angélique in 1652: 'Allow me to tell you that you would be wrong to apologize for the disorder of your discourse and of your thoughts, because, if they were otherwise, things would not be in order, especially for a person belonging to your profession. As there is a wisdom which is folly before God, there is also an order which is disorder, and in consequence, there is a folly which is wisdom and a disorder which is the true rule.' This being exactly the case of the virus, I decided not to apologize.
We can apply these words very aptly to a virus—of the bacteria-infecting kind known as bacteriophage. When a phage particle enters a cell, it loses its infective power and its identity as a particle. Generally its entrance into the cell is followed within 15 minutes to an hour by the emergence of a new generation of infectious virus particles. Sometimes, however, there is no immediate pathological event. The genetic material of the virus that has passed into the cell combines with the genetic material of the cell itself. In doing so it is converted into something that has been named a 'provirus,' meaning before virus. Days or years afterward the provirus may suddenly develop into virus and the bacterium give rise to a group of virus particles.
The term provirus needs some explanation. The expression 'proman' would certainly not evoke the idea of a human egg, from which Homo sapiens always develops, but rather that of an evolutionary ancestor of man which would have to undergo a genetic transformation to become man. A provirus may perhaps correspond to an evolutionary ancestor of a virus. But it is also much more than that.
Before attacking the question of the nature of proviruses, we must know something about viruses themselves. What is a virus? We shall leave out of the discussion the much debated issue as to whether viruses are living organisms or not; our concern is to find out how they differ from 'normal' organisms of the microbiologist's world. The two attributes that are usually thought to define viruses are their very small size and the fact that they can multiply only inside living cells—usually requiring a specific kind of cell host. But to learn more about their peculiarities let us go beyond this definition and compare viruses with other small biological units.
First of all, how does a virus differ from a cell? Most cells are capable of reproducing themselves: they possess the genetic material which is the basis of heredity and the tools necessary to synthesize the essential building blocks and to organize these into a structure just like themselves. We can see three important differences between a cell and a virus, taking bacteriophage as a typical virus: (1) whereas cells contain both desoxyribonucleic acid (DNA) and ribonucleic acid (RNA), the phage contains only DNA; (2) whereas cells are reproduced from essentially all their constituents, bacteriophage is reproduced from its nucleic acid; (3) whereas cells are able to grow and to divide, the virus particle as such is unable to grow or to undergo fission. Bacterial viruses are never produced directly by division of an existing virus; invariably they are formed by organization of material produced in the host cell.
Next we must consider whether viruses bear any likeness to the particles within a cell, particularly the particles called plasmagenes. Here differences are less easy to find. The theory has been proposed that viruses may originate as mutated plasmagenes. But we know that some plasmagenes (e.g., the chloroplasts of green plants) can grow and divide. Furthermore, plasmagenes are not pathogenic or lethal to the cell, as virus particles are. Let us just note, for the time being, that nothing which resembles a bacteriophage in its properties, life cycle, shape or organization has been found in normal cells.
Let us now consider the peculiar behavior of the virus. The virus particle as such is only the beginning and the end of a life cycle. Its only physiological function is to obtain entry of the virus' genetic material into the host cell. After this occurs, what remains of the virus is devoid of infectious power. There follows a vegetative phase in which the specific constituents for new viruses are produced. Finally these constituents are organized into virus particles, which are liberated by lysis (dissolution) of the cell. The whole process usually takes from 15 to 60 minutes.
But a bacterial virus may multiply in another way, and this is where the provirus enters the picture. Ordinarily the virus nucleic acid passed into a cell proceeds promptly to multiply and to synthesize specific protein material for new phage particles. Sometimes, however, the nucleic acid may anchor onto a bacterial chromosome and act as if it were a normal constituent of the cell. It behaves as a bacterial gene, being replicated at each bacterial division and transmitted to each daughter bacterium. This is what we call a provirus. It is a potential virus; it may eventually give rise to virus particles. In the meantime the bacterial offspring go on growing and dividing as normal bacteria, and each daughter bacterium yields progeny capable of producing viruses. In other words, the ability to produce viruses is perpetuated inside the bacterium; no new infection from outside is needed.
Bacteria containing proviruses are called lysogenic. When a small number of such bacteria are broken down, no infectious particles can be found. This means that the provirus is not infectious. And yet in every large population of these bacteria some mature bacteriophage particles appear. From time to time a bacterium in such a culture suddenly disappears, and about 100 phage particles emerge. The probability of a lysogenic bacterium spontaneously giving rise to viruses varies from 1/100 to 1/100,000. In some systems the probability is apparently independent of external factors; it cannot be modified. In other lysogenic systems phage production may be initiated at will by inducing agents, such as X-rays, ultraviolet rays, nitrogen mustard and other substances—all of which are known to be capable of producing mutation. Within 30 to 60 minutes after exposure to one of these agents, practically all of the bacteria produce viruses and lyse.
How do lysogenic bacteria produce viruses? Before discussing this question we must know more about the proviruses. We are inclined to think that proviruses originally arose as mutants of normal bacterial genes. Whatever their origin, the reservoir of bacterial viruses seems to be the provirus-carrying bacteria. These bacteria may have perpetuated provirus, that is to say, the hereditary ability to produce virus, for many thousands of years.
The study of lysogenic bacteria has led to a clear picture of the provirus. Apparently it does not contain virus protein, for lysogenic bacteria do not cause the production of specific antibodies to phage protein in experimental animals. It is therefore tempting to visualize the provirus as a large molecule of nucleic acid. Secondly, the provirus is associated with a certain genetic character of bacteria and is located at a specific site on a bacterial chromosome. Thirdly, two genetically related proviruses in a bacterium may cross over and recombine. Fourth, a lysogenic bacterium is immune to infection by a phage particle related genetically to its provirus, though it can be killed by an unrelated phage. As long as the provirus remains in that state, a genetically related superinfecting phage is unable to develop into phage. Finally, the mere presence of the provirus may modify the properties of a bacterium: it may endow certain bacteria with the ability to produce a toxin they could not otherwise make, or it may change the typical appearance of bacterial colonies. Things happen as if the provirus either carries a specific gene or modifies the neighboring bacterial genes. From all these data it may be concluded that provirus is the bacterial virus' genetic material, bound to a specific site in the bacterium and responsible for a specific bacterial immunity.
Now it is difficult to imagine that this immunity is due only to the presence of the provirus. A particle cannot exert a specific action by its mere presence. The only way the provirus can make the bacterium immune—that is, prevent multiplication of a virus invader—is by modifying or blocking a specific activity of the bacterium necessary for that reproduction. And the provirus can do this only if it is present at a specific site. As a matter of fact, we can account for all the properties of proviruses and of lysogenic bacteria by the hypothesis that the provirus is the genetic material of the virus anchored at a given site in the bacterium. The genetic material of an infecting virus becomes a provirus when and because it becomes bound at that site to a specific receptor, which modifies the material. It then gives the bacterium immunity against genetically related infecting particles. An inducing agent such as ultraviolet rays destroys the immunity because it displaces the genetic material of the virus from its specific site.
For a long time virologists have concentrated on the virus particle itself. Yet the particle is only a prelude to the infection. During the longest and most important part of the life cycle, the pathogenic phase in a cell, no virus particle is present. As a matter of fact, disappearance of the virus particle is the sine qua non for the development of the cellular lesion. Indeed, there are cases in which all the bacteria in a lysogenic population die although very few of them produce bacteriophage particles; the cells are killed by a defective development of proviruses initiated by an inducing agent. One could even conceive of a condition in which the probability of the virus ever appearing would be infinitely small, that is to say, practically absent. Some bacteria actually carry a gene which can initiate the synthesis of a protein lethal to themselves. But that is another story.
Biologists have long been accustomed to think of death in terms of the destruction or alteration of some vital structure. We have been less inclined to think of living cells as carrying the seeds of their own destruction, or of the possibility that lethal agents may kill in more than one way. For example, X-rays sometimes kill by destroying essential structures, but they may also destroy a cell by inducing a gene to express its lethal potentiality. This potentiality is sometimes the power to start a new synthesis which may or may not end in virus particles.
To what extent are the phenomena disclosed in bacteria valid for higher organisms? May animal or plant cells perpetuate proviruses? Are some viral diseases of man the result of the activation of a provirus? May immunity to virus diseases be explained in terms of proviruses? Do the findings concerning lysogeny have any bearing on cancer? Let us recall that the inducing agents which can trigger proviruses to give rise to viruses are all not only mutagenic but also carcinogenic—radiations, nitrogen mustard and so on. It is indeed tempting to theorize that carcinogens may induce malignancy by initiating the formation of a pathological structure from a provirus-like material. Many facts are in favor of the hypothesis that proviruses originate some animal diseases, but the problem cannot be discussed within the limits of this article. Suffice it to say that this is, at any rate, a working hypothesis.
I have tried to outline the concept of the provirus, to analyze its relations with the concept of the cell and of the virus and to show the impact of the newly acquired knowledge on our conceptions of cellular disease. The common denominator of the various phases of the life cycle of a virus is the genetic material—the nucleic acid—which may exist in three states: infectious, proviral and vegetative. Throughout these three states the genetic material apparently remains essentially the same in structure, but it changes radically in dynamic potentialities and behavior. The virus particle, the end product of the vegetative phase, is a quiescent nucleoprotein particle, unable to grow or to divide. The provirus is an integrated nucleic acid, which behaves like a gene and is replicated like the host genes. Neither the virus particle nor the provirus is pathogenic per se; their pathogenic property is only potential. The only pathogenic phase of the virus is the vegetative phase, during which the specific viral nucleic acid multiplies and during which the specific viral protein is synthesized. Things happen as if the synthesis of the protein is responsible for pathogenicity.
The provirus produces provirus; it is order. The vegetative particle produces virus particles and a disease of the host; it is disorder. The virus particle does not produce anything; it is an extremely conservative particle—the absence of any activity, that is to say, a kind of order. Thus the virus is an alternation of order and disorder.
As a result, my presentation of the subject may seem somewhat disordered. For this I had decided to apologize, when I came across an unpublished letter which Martin de Barcos, Abbot of Saint-Cyran, wrote to Mother Angélique in 1652: 'Allow me to tell you that you would be wrong to apologize for the disorder of your discourse and of your thoughts, because, if they were otherwise, things would not be in order, especially for a person belonging to your profession. As there is a wisdom which is folly before God, there is also an order which is disorder, and in consequence, there is a folly which is wisdom and a disorder which is the true rule.' This being exactly the case of the virus, I decided not to apologize.
Sep 10, 2008
1998: Space Exploration: Space Shuttle Completes Last Mission to Mir
A three-year cooperative space exploration program between Russia and the United States ended on June 12, 1998, as the space shuttle Discovery touched down at Florida's John F. Kennedy Space Center. The Discovery's mission was the last of ten shuttle flights to the Russian space station Mir which were intended to boost cooperation in preparation for construction of the International Space Station (ISS).
Returning to earth aboard Discovery was astronaut Andrew Thomas, who spent more than four months aboard Mir and was the last of seven U.S. astronauts to stay on the Russian station. Thomas and the other astronauts used their time on the 12-year-old space station to conduct experiments and test technologies planned for use on the ISS. The program also provided scientists with valuable information about the long-term effects of weightlessness on the human body.
The first space shuttle mission to Mir took place in February 1995. The first U.S. astronaut onboard Mir was Norman Thagard, who stayed from March 1995 to July 1995. The others were Shannon Lucid, John Blaha, Jerry Linenger, Mike Foale, and David Wolf. The U.S. astronauts and their Russian colleagues endured several mishaps during the program, including a collision with a Russian supply vehicle, an onboard fire, and numerous computer problems.
A total of 15 countries—the United States, Russia, Canada, Japan, and members of the European Space Agency (ESA)—will contribute to the ISS. The first component was scheduled to be launched into orbit in late 1998. The Russian Space Agency reportedly planned to allow Mir to fall out of orbit and burn up in the atmosphere some time in 1999. Mir was launched in 1986 and was originally intended to last only five year.
columbia disaster
The space shuttle Columbia broke apart and burned up while reentering Earth’s atmosphere over Texas on February 1, 2003. The entire seven-member crew was killed as they returned to Earth after completing a series of scientific experiments. Investigation of the disaster pointed to structural failure of the heat-shielding system for the shuttle’s left wing. Sensors inside the wing recorded unusually high temperatures just before NASA lost contact with the shuttle. The investigation determined that the wing was damaged during liftoff when it was struck by a piece of insulation foam from the external fuel tank, opening a hole in the left wing. On reentry, superheated gases in the atmosphere penetrated the left wing, dooming the craft and the crew. The space shuttle fleet was grounded until July 2005 when the shuttle Discovery returned to space. However, during the launch of Discovery, a chunk of insulation foam broke off again from the external fuel tank, despite a more than two-year and nearly $1 billion effort to prevent a recurrence of the problem. Although the Discovery appeared to be undamaged, NASA announced that it was indefinitely suspending further shuttle flights.
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