If you've grown tired of answering those annoying browser prompts every time a website wants to show you notifications or know your location, you can turn the messages off forever with a few clicks in every major browser. Scroll down below for your browser and where to locate the appropriate settings in Chrome (desktop and Android), Firefox, Opera, Edge, Internet Explorer and Safari (desktop and iOS).
Chrome
From the drop down menu, select Settings > Advanced (scroll down) > Content settings.
From Chrome's content settings you can click into 'Location' and 'Notifications' separately to disable each. This will block the pop-ups forever while also preventing websites from knowing your location and sending you notifications.
Chrome (Android)
The exact same settings exist on the mobile version of Chrome found in Android devices. Although we wouldn't outright disable location settings on the browser like we'd do on the desktop (for obvious useful reasons), if one of your favorite websites annoys you with these kind of prompts, you can always disable them on a per-site basis.
From the Chrome menu button on the top right corner, select Settings. Under Settings, scroll down to Advanced > Site settings. There you will find discrete settings for both Location and Notifications, the default is set to "Ask first," you can set those to "Block" which will stop sites to prompt you for either.
Firefox
In the address bar type "about:config" and hit Enter. Accept the risk when prompted.
If you made it under the hood safely, use the search bar to find the following entries: dom.webnotifications.enabled and geo.enabled.
Double-clicking on each entry will set their values to false, which is what you want to do if you're trying to disable the pop-ups.
Opera
From the drop down menu, select Settings and then go to the Websites tab.
Location and notification prompts are both listed halfway through the website section of Opera's menu settings -- set both of them to "do not allow...".
Microsoft Edge
Open Windows 10's Settings (search 'settings' via Start), then go to Privacy > Location.
Scroll down in this section to 'Choose apps that can use your location' and you can customize the settings for Microsoft Edge along with other applications. Note that disabling 'Location service' on the top of the same page will block all apps from using your location.
Open Edge's settings menu, go to View advanced settings > Notifications (manage).
Websites that can show notifications will be listed here so you can customize which ones are able to send them. Likewise, from the privacy settings in the Windows 10 menu mentioned above, the notifications section will let you block them from all applications.
Internet Explorer
Open IE's drop down menu, go to Internet options, select the Privacy tab.
In the privacy tab, uncheck 'never allow websites to request your physical location' and then click into "Settings" for the option to uncheck notifications from when a pop-up is blocked (this isn't the same as the notifications blocked in other browsers but nonetheless noteworthy).
Safari (macOS)
From Safari's drop-down menu, select Preferences then go to the Websites tab. On the left side menu you'll find Location and Notifications.
On Location, you will find per website settings based on the currently opened tabs. But to deny location to all websites, on the bottom right corner select where it says "When visiting other websites:" select Deny.
On the Notifications settings, uncheck the option where it says "Allow websites to ask for permission to send push notifications."
Safari (iPhone /iOS)
On iOS devices, location settings are more strictly managed by the operating system. Go to Settings > Privacy > Location Services. Find the setting for Safari Websites and set it to "Never."
Wednesday, January 15, 2020
Useful Security Tips
Lock your computer if you get up Sick of your "friends" going onto your computer at work or home and posting things on your Facebook/Twitter page on your behalf? It's certainly an annoyance, but an easy one to prevent.
Windows + L will lock your system right away, requiring a password (if you've set one) to log in again.
On macOS use Cmd + Option + Power to log off. On the latest revision of macOS (High Sierra) a quicker option to simply lock the screen was added which works using the shortcut Cmd + Ctrl + Q.
Scan suspicious files with VirusTotal If you're worried about a file being infected, you can upload it to Virus Total to have it checked by a few dozen antivirus engines from the cloud. Often times someone has already uploaded the same file, sparing you the wait.
See who is logged on to your router Software such as Wireless Network Watcher makes this particularly easy and even has alarms for when someone new appears. You can also do this by logging into your router (common router IP addresses) and checking for a list of wireless clients which should display the name of the device, its currently assigned IP address and its MAC address.
Permanently remove deleted data so software such as Recuva can't undelete files/folders Open a command prompt and enter cipher /w:C: to wipe deleted files from your C: drive (change the letter to target a different drive or folder). If you need to go the extra mile and use a file shredder program, check out Eraser (Windows) and FileShredder (Mac).
Read installers Even major programs can install toolbars and other unwanted pieces of software during installation. Take a few seconds to read each step to make sure you are not agreeing to install something other than the program you were actually seeking. Far too often people just push next over and over, and end up with a browser covered in various search bars that just aren't needed. In the worst of scenarios, these can have nefarious intentions.
Run programs on an infected PC Malware may prevent a computer from running certain programs. Changing the name of the .exe file can often override this. If that doesn't work, changing the extension to .com is another useful alternative, and the program will still be able to run despite the extension change.
Windows + L will lock your system right away, requiring a password (if you've set one) to log in again.
On macOS use Cmd + Option + Power to log off. On the latest revision of macOS (High Sierra) a quicker option to simply lock the screen was added which works using the shortcut Cmd + Ctrl + Q.
Scan suspicious files with VirusTotal If you're worried about a file being infected, you can upload it to Virus Total to have it checked by a few dozen antivirus engines from the cloud. Often times someone has already uploaded the same file, sparing you the wait.
See who is logged on to your router Software such as Wireless Network Watcher makes this particularly easy and even has alarms for when someone new appears. You can also do this by logging into your router (common router IP addresses) and checking for a list of wireless clients which should display the name of the device, its currently assigned IP address and its MAC address.
Permanently remove deleted data so software such as Recuva can't undelete files/folders Open a command prompt and enter cipher /w:C: to wipe deleted files from your C: drive (change the letter to target a different drive or folder). If you need to go the extra mile and use a file shredder program, check out Eraser (Windows) and FileShredder (Mac).
Read installers Even major programs can install toolbars and other unwanted pieces of software during installation. Take a few seconds to read each step to make sure you are not agreeing to install something other than the program you were actually seeking. Far too often people just push next over and over, and end up with a browser covered in various search bars that just aren't needed. In the worst of scenarios, these can have nefarious intentions.
Run programs on an infected PC Malware may prevent a computer from running certain programs. Changing the name of the .exe file can often override this. If that doesn't work, changing the extension to .com is another useful alternative, and the program will still be able to run despite the extension change.
Useful File Management Tricks
Rename a file quickly Right-clicking and selecting rename is not very efficient. Instead press F2 while a file is selected to change its name. To alter the name of another file, type Tab without deselecting the current file. On Macs, hitting Enter will rename (which may sound counter-intuitive to Windows users) while Cmd + O is used to open.
Cloud backup important files If you're working on a critical project, make sure you aren't backing up locally only. Services like Dropbox, Google Drive, or any of the other popular cloud storage solutions will do the legwork for you in the background. Of course, you can also throw the files on a thumb drive or external HDD to be extra safe, but backing up to the cloud can be done seamlessly.
Rename files sequentially in Windows or Mac You actually don't need to download any programs to perform a batch file rename. Instead, you can select all the files you want to change, right-click the first one in the list, select rename (or use F2), and type in the name. This will automatically change all the other files with the same root name with a suffix: (1), (2), and so on.
On Mac, you can do something similar. Select the files, then right click and an option to rename the whole batch as a series will show up.
Select multiple files using the keyboard To select a bunch of files using your keyboard, you can press Shift + Down Arrow to select a single file or Shift + Page Down to select a large group of files at one time. Ctrl + A will select everything.
Right click drag files and folders in Windows And you'll be presented with a context menu containing options to move, copy, zip or create a shortcut.
Cloud backup important files If you're working on a critical project, make sure you aren't backing up locally only. Services like Dropbox, Google Drive, or any of the other popular cloud storage solutions will do the legwork for you in the background. Of course, you can also throw the files on a thumb drive or external HDD to be extra safe, but backing up to the cloud can be done seamlessly.
Rename files sequentially in Windows or Mac You actually don't need to download any programs to perform a batch file rename. Instead, you can select all the files you want to change, right-click the first one in the list, select rename (or use F2), and type in the name. This will automatically change all the other files with the same root name with a suffix: (1), (2), and so on.
On Mac, you can do something similar. Select the files, then right click and an option to rename the whole batch as a series will show up.
Select multiple files using the keyboard To select a bunch of files using your keyboard, you can press Shift + Down Arrow to select a single file or Shift + Page Down to select a large group of files at one time. Ctrl + A will select everything.
Right click drag files and folders in Windows And you'll be presented with a context menu containing options to move, copy, zip or create a shortcut.
Useful Web Browsing Tricks and shortcuts
Jump to address bar There are a number of ways to jump right to the address bar from anywhere in browser. Pressing Ctrl + L, F6, and Alt + D all accomplish this goal.
Automatically add www. and .com to a URL You can shave off a couple of seconds typing in a URL by simply click Ctrl + Enter after you type the name of the site. Need .net instead of .com? Press Ctrl + Shift + Enter instead.
Cycle through open tabs Pressing Ctrl + Tab while in a browser will flip between each one (Ctrl + Shift + Tab to go backwards). This can be much faster than moving the mouse and clicking on a tab. Ctrl + Num (1, 2, 3, 4, n..) will also take you to certain tab in that numeric order. Ctrl + 9 always brings you to the very last tab, even if it's beyond the ninth one.
Scroll through pages with the space-bar Tapping the space-bar on a website will scroll down in full page chunks and hitting shift + space will take you back up.
Instant image search (Chrome only) If you hold down the "S" key and right click on an image, it will open an image search on a new tab.
Use private browsing The uses for not having cookies and history saved are obvious for certain activities, you know, like shopping for gifts on a shared computer (of course!). Pressing Ctrl + Shift + N will launch a new private in Chrome, Ctrl + Shift + P will do it in Firefox and Internet Explorer.
Convert your browser into a notepad Type this into the address bar and you can write notes. Alternatively, while not as fast. Use Google Keep or Gmail's compose mail to write notes and have those saved on the cloud as you type and go.
Icon-only bookmarks on your toolbar You can delete the name of your bookmarks leaving only the icon so they take up less space on the toolbar. In Chrome: right click the bookmark > edit > delete the name and save.
Use the scroll wheel Put your middle mouse button to use by clicking on links to automatically open them in a new tab/window. Also if you use the scroll wheel button on a tab, it will close it.
Copy links quicker Right click the link like usual but tap E on your keyboard to copy the link.
Make content editable Bring up the console on Chrome or Firefox (right click, Inspect). On the console enter the command document.designMode = "on" that will let you edit any text on the screen.
Zoom In, Reset Zoom Use the browser magnifier to adjust a website for more comfortable reading. Ctrl/Cmd + (plus/minus sign) does the trick. To reset to the default zoom level use Ctrl + 0.
Thursday, January 9, 2020
What is Neurochemistry?
Neurochemistry is the study of chemicals, including neurotransmitters and other molecules such as psycho-pharmaceuticals and neuropeptides, that control and influence the physiology of the nervous system. This field within neuroscience examines how neurochemicals influence the operation of neurons, synapses, and neural networks. Neurochemists analyze the biochemistry and molecular biology of organic compounds in the nervous system, and their roles in such neural processes including cortical plasticity, neurogenesis, and neural differentiation.
Neurochemistry of PTSD
One of the major areas of research within neurochemistry is looking at how post-traumatic stress disorder alters the brain. Neurotransmitter level fluctuations can dictate whether a PTSD episode occurs and how long the episode lasts. Dopamine has less of an effect than norepinephrine. Different neurochemicals can affect different parts of the brain. This allows drugs to be used for PTSD to not have an undesired effect on other brain processes. An effective medication to help alleviate nightmares associated with PTSD is Prazosin.
Neurochemistry of PTSD
One of the major areas of research within neurochemistry is looking at how post-traumatic stress disorder alters the brain. Neurotransmitter level fluctuations can dictate whether a PTSD episode occurs and how long the episode lasts. Dopamine has less of an effect than norepinephrine. Different neurochemicals can affect different parts of the brain. This allows drugs to be used for PTSD to not have an undesired effect on other brain processes. An effective medication to help alleviate nightmares associated with PTSD is Prazosin.
What is Provirus?
A provirus is a virus genome that is integrated into the DNA of a host cell. In the case of bacterial viruses (bacteriophages), proviruses are often referred to as prophages.
This state can be a stage of virus replication, or a state that persists over longer periods of time as either inactive viral infections or an endogenous viral element. In inactive viral infections the virus will not replicate itself except through replication of its host cell. This state can last over many host cell generations.
Endogenous retroviruses are always in the state of a provirus. When a (non-endogenous) retrovirus invades a cell, the RNA of the retrovirus is reverse-transcribed into DNA by reverse transcriptase, then inserted into the host genome by an integrase.
A provirus does not directly make new DNA copies of itself while integrated into a host genome in this way. Instead, it is passively replicated along with the host genome and passed on to the original cell's offspring; all descendants of the infected cell will also bear proviruses in their genomes. This is known as lysogenic viral reproduction.Integration can result in a latent infection or a productive infection. In a productive infection, the provirus is transcribed into messenger RNA which directly produces new virus, which in turn will infect other cells via the lytic cycle. A latent infection results when the pro-virus is transcription-ally silent rather than active.
A latent infection may become productive in response to changes in the host's environmental conditions or health; the provirus may be activated and begin transcription of its viral genome. This can result in the destruction of its host cell because the cell's protein synthesis machinery is hijacked to produce more viruses.
Proviruses may account for approximately 8% of the human genome in the form of inherited endogenous retroviruses.
A provirus not only refers to a retrovirus but is also used to describe other viruses that can integrate into the host chromosomes, another example being adeno-associated virus. Not only eukaryotic viruses integrate into the genomes of their hosts; many bacterial and archaeal viruses also employ this strategy of propagation. All families of bacterial viruses with circular (single-stranded or double-stranded) DNA genomes or replicating their genomes through a circular intermediate (e.g., tailed dsDNA viruses) have temperate members.
This state can be a stage of virus replication, or a state that persists over longer periods of time as either inactive viral infections or an endogenous viral element. In inactive viral infections the virus will not replicate itself except through replication of its host cell. This state can last over many host cell generations.
Endogenous retroviruses are always in the state of a provirus. When a (non-endogenous) retrovirus invades a cell, the RNA of the retrovirus is reverse-transcribed into DNA by reverse transcriptase, then inserted into the host genome by an integrase.
A provirus does not directly make new DNA copies of itself while integrated into a host genome in this way. Instead, it is passively replicated along with the host genome and passed on to the original cell's offspring; all descendants of the infected cell will also bear proviruses in their genomes. This is known as lysogenic viral reproduction.Integration can result in a latent infection or a productive infection. In a productive infection, the provirus is transcribed into messenger RNA which directly produces new virus, which in turn will infect other cells via the lytic cycle. A latent infection results when the pro-virus is transcription-ally silent rather than active.
A latent infection may become productive in response to changes in the host's environmental conditions or health; the provirus may be activated and begin transcription of its viral genome. This can result in the destruction of its host cell because the cell's protein synthesis machinery is hijacked to produce more viruses.
Proviruses may account for approximately 8% of the human genome in the form of inherited endogenous retroviruses.
A provirus not only refers to a retrovirus but is also used to describe other viruses that can integrate into the host chromosomes, another example being adeno-associated virus. Not only eukaryotic viruses integrate into the genomes of their hosts; many bacterial and archaeal viruses also employ this strategy of propagation. All families of bacterial viruses with circular (single-stranded or double-stranded) DNA genomes or replicating their genomes through a circular intermediate (e.g., tailed dsDNA viruses) have temperate members.
Mechanical wave
A mechanical wave is a wave that is an oscillation of matter, and therefore transfers energy through a medium. While waves can move over long distances, the movement of the medium of transmission—the material—is limited. Therefore, the oscillating material does not move far from its initial equilibrium position. Mechanical waves transport energy. This energy propagates in the same direction as the wave. Any kind of wave (mechanical or electromagnetic) has a certain energy. Mechanical waves can be produced only in media which possess elasticity and inertia.
A mechanical wave requires an initial energy input. Once this initial energy is added, the wave travels through the medium until all its energy is transferred. In contrast, electromagnetic waves require no medium, but can still travel through one.
One important property of mechanical waves is that their amplitudes are measured in an unusual way, displacement divided by (reduced) wavelength. When this gets comparable to unity, significant nonlinear effects such as harmonic generation may occur, and, if large enough, may result in chaotic effects. For example, waves on the surface of a body of water break when this dimensionless amplitude exceeds 1, resulting in a foam on the surface and turbulent mixing. Some of the most common examples of mechanical waves are water waves, sound waves, and seismic waves.
There are three types of mechanical waves: transverse waves, longitudinal waves, and surface waves.
Transverse wave
It is the form of wave in which particles of medium vibrates about their mean position perpendicular to the direction of motion of wave.
To see an example, move an end of a Slinky (whose other end is fixed) to the left-and-right of the Slinky, as opposed to to-and-fro. Light also has properties of a transverse wave, although it is an electromagnetic wave.
Longitudinal wave
Longitudinal waves cause the medium to vibrate parallel to the direction of the wave. It consists of multiple compression and rarefaction. The rarefaction is the farthest distance apart in the longitudinal wave and the compression is the closest distance together. The speed of the longitudinal wave is increased in higher index of refraction, due to the closer proximity of the atoms in the medium that is being compressed. Sound is a longitudinal wave.
Surface waves
This type of wave travels along the surface or interface between two media. An example of a surface wave would be waves in a pool, or in an ocean, lake, or any other type of water body. There are two types of surface waves, namely Rayleigh waves and Love waves.
Rayleigh waves, also known as ground roll, are waves that travel as ripples with motion similar to those of waves on the surface of water. Rayleigh waves are much slower than body waves, at roughly 90% of the velocity of bulk waves[clarify] for a typical homogeneous elastic medium. Rayleigh waves have energy losses only in two dimensions and are hence more destructive in earthquakes than conventional bulk waves, such as P-waves and S-waves, which lose energy in all three directions.
A Love wave is a surface wave having horizontal waves that are shear or transverse to the direction of propagation. They usually travel slightly faster than Rayleigh waves, at about 90% of the body wave velocity, and have the largest amplitude.
A mechanical wave requires an initial energy input. Once this initial energy is added, the wave travels through the medium until all its energy is transferred. In contrast, electromagnetic waves require no medium, but can still travel through one.
One important property of mechanical waves is that their amplitudes are measured in an unusual way, displacement divided by (reduced) wavelength. When this gets comparable to unity, significant nonlinear effects such as harmonic generation may occur, and, if large enough, may result in chaotic effects. For example, waves on the surface of a body of water break when this dimensionless amplitude exceeds 1, resulting in a foam on the surface and turbulent mixing. Some of the most common examples of mechanical waves are water waves, sound waves, and seismic waves.
There are three types of mechanical waves: transverse waves, longitudinal waves, and surface waves.
Transverse wave
It is the form of wave in which particles of medium vibrates about their mean position perpendicular to the direction of motion of wave.
To see an example, move an end of a Slinky (whose other end is fixed) to the left-and-right of the Slinky, as opposed to to-and-fro. Light also has properties of a transverse wave, although it is an electromagnetic wave.
Longitudinal wave
Longitudinal waves cause the medium to vibrate parallel to the direction of the wave. It consists of multiple compression and rarefaction. The rarefaction is the farthest distance apart in the longitudinal wave and the compression is the closest distance together. The speed of the longitudinal wave is increased in higher index of refraction, due to the closer proximity of the atoms in the medium that is being compressed. Sound is a longitudinal wave.
Surface waves
This type of wave travels along the surface or interface between two media. An example of a surface wave would be waves in a pool, or in an ocean, lake, or any other type of water body. There are two types of surface waves, namely Rayleigh waves and Love waves.
Rayleigh waves, also known as ground roll, are waves that travel as ripples with motion similar to those of waves on the surface of water. Rayleigh waves are much slower than body waves, at roughly 90% of the velocity of bulk waves[clarify] for a typical homogeneous elastic medium. Rayleigh waves have energy losses only in two dimensions and are hence more destructive in earthquakes than conventional bulk waves, such as P-waves and S-waves, which lose energy in all three directions.
A Love wave is a surface wave having horizontal waves that are shear or transverse to the direction of propagation. They usually travel slightly faster than Rayleigh waves, at about 90% of the body wave velocity, and have the largest amplitude.
What is galactic ridge?
The galactic ridge is a region of the inner galaxy that is coincident with the galactic plane of the Milky Way. It can be seen from Earth as a band of stars which is interrupted by 'dust lanes'. In these 'dust lanes' the dust in the gaseous galactic disk (or plane) blocks the visible light of the background stars. Due to this, many of the most interesting features of the Milky Way can only be viewed in X-rays. Along with the point X-ray sources which populate the Milky Way, an apparently diffuse X-ray emission concentrated in the galactic plane is also observed. This is known as the galactic ridge X-ray emission (GRXE). These emissions were originally discovered by Diana Worrall and collaborators in 1982, and since then the origins of these emissions have puzzled astrophysicists around the globe.
It was initially believed, due to the difficulty of resolving the GRXE into point sources, that the x-ray emissions were truly diffuse in nature and that their origin might be a Galactic plasma rather than distant stellar sources. It was thought to be caused by low energy cosmic rays interacting with cold gas in the region, which heated up the gas and caused it to emit X-rays.However it was discovered that the temperature of a gas producing such an emission would have to be around tens of millions of degrees. This temperature is far too high for a gas to be bound gravitationally to the galaxy. Therefore, it was proposed that the GRXE might be caused by many extremely remote and outlying stars. In 2009, after decades of attempting to resolve the GRXE, Mikhail Revnivtsev, his partner Sazonov and their colleges managed to resolve approximately 80% of the emissions over the course of 12 days using the Chandra X-ray observatory. During this time period a total of 473 sources of x-ray emission were detected in an area that is significantly smaller than the size of a Full Moon. This is one of the highest densities of x-ray sources ever seen in our Galaxy. Due to this amazing discovery it is now thought that about 80% of the emission comes from discrete sources such as white dwarfs and stars with active coronae.
However, recent work by researchers at the Max Planck Institute for Astrophysics suggests that the GRXE may indeed consist of an additional, diffuse component after all. This diffuse component could arise not from the thermal emission of a very hot plasma but from the reprocessing by the interstellar gas of the X-ray radiation produced by luminous X-ray binary sources located in the Galaxy. X-ray binaries are the most luminous sources of X-rays in galaxies such as the Milky Way. These binary systems emit X-ray radiation when material or substance from a so-called donor star falls into the strong gravitational field of a compact object, such as a neutron star or a black hole. This X-ray radiation illuminates the atoms and molecules in the Galactic interstellar gas, which then scatter the incoming photons in different directions and at different energies. The resulting emission appears truly diffuse to the viewer.
The Galactic Ridge has a width of 5° latitude (b) and ±40° longitude (l) in the Galactic coordinate system.
The first instrument that was able to measure diffuse X-ray emission was the HEAO A2 (High Energy Astrophysical Observatory). However it was created to study the large-scale structure of the galaxy and the universe, and to yield high-quality spatial and spectral data in the X-ray region. Still, the HEAO A2 produced valuable information on discrete X-ray sources such as binary star systems, hot white dwarfs, cataclysmic variables and supernova remnants. The HEAO A2 also allowed for the study of extragalactic objects, for example radio galaxies, Seyfert galaxies, and quasars. Elihu Boldt was the principal investigator of the HEAO A2 instrument, however he worked alongside G. Gamire on the project. The HEAO A2 was launched into space in 1977, where its job was to scan the sky for approximately 17 months. It (the HEAO A2) produced the first low-background, all-sky maps in the 2-60 keV band, and for its time the HEAO A2 produced the best spectra ever obtained over 2-60 keV energy range.
It was initially believed, due to the difficulty of resolving the GRXE into point sources, that the x-ray emissions were truly diffuse in nature and that their origin might be a Galactic plasma rather than distant stellar sources. It was thought to be caused by low energy cosmic rays interacting with cold gas in the region, which heated up the gas and caused it to emit X-rays.However it was discovered that the temperature of a gas producing such an emission would have to be around tens of millions of degrees. This temperature is far too high for a gas to be bound gravitationally to the galaxy. Therefore, it was proposed that the GRXE might be caused by many extremely remote and outlying stars. In 2009, after decades of attempting to resolve the GRXE, Mikhail Revnivtsev, his partner Sazonov and their colleges managed to resolve approximately 80% of the emissions over the course of 12 days using the Chandra X-ray observatory. During this time period a total of 473 sources of x-ray emission were detected in an area that is significantly smaller than the size of a Full Moon. This is one of the highest densities of x-ray sources ever seen in our Galaxy. Due to this amazing discovery it is now thought that about 80% of the emission comes from discrete sources such as white dwarfs and stars with active coronae.
However, recent work by researchers at the Max Planck Institute for Astrophysics suggests that the GRXE may indeed consist of an additional, diffuse component after all. This diffuse component could arise not from the thermal emission of a very hot plasma but from the reprocessing by the interstellar gas of the X-ray radiation produced by luminous X-ray binary sources located in the Galaxy. X-ray binaries are the most luminous sources of X-rays in galaxies such as the Milky Way. These binary systems emit X-ray radiation when material or substance from a so-called donor star falls into the strong gravitational field of a compact object, such as a neutron star or a black hole. This X-ray radiation illuminates the atoms and molecules in the Galactic interstellar gas, which then scatter the incoming photons in different directions and at different energies. The resulting emission appears truly diffuse to the viewer.
The Galactic Ridge has a width of 5° latitude (b) and ±40° longitude (l) in the Galactic coordinate system.
The first instrument that was able to measure diffuse X-ray emission was the HEAO A2 (High Energy Astrophysical Observatory). However it was created to study the large-scale structure of the galaxy and the universe, and to yield high-quality spatial and spectral data in the X-ray region. Still, the HEAO A2 produced valuable information on discrete X-ray sources such as binary star systems, hot white dwarfs, cataclysmic variables and supernova remnants. The HEAO A2 also allowed for the study of extragalactic objects, for example radio galaxies, Seyfert galaxies, and quasars. Elihu Boldt was the principal investigator of the HEAO A2 instrument, however he worked alongside G. Gamire on the project. The HEAO A2 was launched into space in 1977, where its job was to scan the sky for approximately 17 months. It (the HEAO A2) produced the first low-background, all-sky maps in the 2-60 keV band, and for its time the HEAO A2 produced the best spectra ever obtained over 2-60 keV energy range.
Cranial electrotherapy stimulation (CES)
Cranial electrotherapy stimulation (CES) is a form of neurostimulation that delivers a small, pulsed, alternating current via electrodes on the head. CES is used with the intention of treating a variety of conditions such as anxiety, depression and insomnia. CES has been suggested as a possible treatment for headaches, fibromyalgia, smoking cessation, and opiate withdrawal, but there is little evidence of effectiveness for many of these conditions and the evidence for use in acute depression is not sufficient to justify it.
Medical uses
A 2014 Cochrane review found insufficient evidence to determine whether or not CES with alternating current is safe and effective for treating depression.
A 2018 systematic review found that evidence is insufficient that CES has clinically important effects on fibromyalgia, headache, neuromusculoskeletal pain, degenerative joint pain, depression, or insomnia; low-strength evidence suggests modest benefit in patients with anxiety and depression.
Description
Electrodes are placed on the ear lobes, maxilla-occipital junction, mastoid processes or temples.
Despite the long history of CES, its underlying principles and mechanisms are still not clear.
CES stimulation of 1 mA (milliampere) has shown to reach the thalamic area at a radius of 13.30 mm. CES has shown to induce changes in the electroencephalogram, increasing alpha relative power and decreasing relative power in delta and beta frequencies.[relevant? – discuss]
CES has also shown to reach cortical and subcortical areas of the brain, in electromagnetic tomography and functional MRI studies. CES treatments have been found to induce changes in neurohormones and neurotransmitters that have been implicated in psychiatric disorders: substantial increases in beta endorphins, adrenocorticotrophic hormone, and serotonin; moderate increases in melatonin and norepinephrine, modest or unquantified increases in cholinesterase, gamma-aminobutyric acid, and dehydroepiandrosterone, and moderate reductions in cortisol.
Medical uses
A 2014 Cochrane review found insufficient evidence to determine whether or not CES with alternating current is safe and effective for treating depression.
A 2018 systematic review found that evidence is insufficient that CES has clinically important effects on fibromyalgia, headache, neuromusculoskeletal pain, degenerative joint pain, depression, or insomnia; low-strength evidence suggests modest benefit in patients with anxiety and depression.
Description
Electrodes are placed on the ear lobes, maxilla-occipital junction, mastoid processes or temples.
Despite the long history of CES, its underlying principles and mechanisms are still not clear.
CES stimulation of 1 mA (milliampere) has shown to reach the thalamic area at a radius of 13.30 mm. CES has shown to induce changes in the electroencephalogram, increasing alpha relative power and decreasing relative power in delta and beta frequencies.[relevant? – discuss]
CES has also shown to reach cortical and subcortical areas of the brain, in electromagnetic tomography and functional MRI studies. CES treatments have been found to induce changes in neurohormones and neurotransmitters that have been implicated in psychiatric disorders: substantial increases in beta endorphins, adrenocorticotrophic hormone, and serotonin; moderate increases in melatonin and norepinephrine, modest or unquantified increases in cholinesterase, gamma-aminobutyric acid, and dehydroepiandrosterone, and moderate reductions in cortisol.
What is Techno-criticism?
Technocriticism is a branch of critical theory devoted to the study of technological change.
Technocriticism treats technological transformation as historically specific changes in personal and social practices of research, invention, regulation, distribution, promotion, appropriation, use, and discourse, rather than as an autonomous or socially indifferent accumulation of useful inventions, or as an uncritical narrative of linear "progress", "development" or "innovation".
Technocriticism studies these personal and social practices in their changing practical and cultural significance. It documents and analyzes both their private and public uses, and often devotes special attention to the relations among these different uses and dimensions. Recurring themes in technocritical discourse include the deconstruction of essentialist concepts such as "health", "human", "nature" or "norm".
Technocritical theory can be either "descriptive" or "prescriptive" in tone. Descriptive forms of technocriticism include some scholarship in the history of technology, science and technology studies, cyberculture studies and philosophy of technology. More prescriptive forms of technocriticism can be found in the various branches of technoethics, for example, media criticism, infoethics, bioethics, neuroethics, roboethics, nanoethics, existential risk assessment and some versions of environmental ethics and environmental design theory.
Figures engaged in technocritical scholarship and theory include Donna Haraway and Bruno Latour (who work in the closely related field of science studies), N. Katherine Hayles (who works in the field of Literature and Science), Phil Agree and Mark Poster (who works in intellectual history), Marshall McLuhan and Friedrich Kittler (who work in the closely related field of media studies), Susan Squier and Richard Doyle (who work in the closely related field of medical sociology), and Hannah Arendt, Walter Benjamin, Martin Heidegger, and Michel Foucault (who sometimes wrote about the philosophy of technology). Technocriticism can be juxtaposed with a number of other innovative interdisciplinary areas of scholarship which have surfaced in recent years such as technoscience and technoethics.
Technocriticism treats technological transformation as historically specific changes in personal and social practices of research, invention, regulation, distribution, promotion, appropriation, use, and discourse, rather than as an autonomous or socially indifferent accumulation of useful inventions, or as an uncritical narrative of linear "progress", "development" or "innovation".
Technocriticism studies these personal and social practices in their changing practical and cultural significance. It documents and analyzes both their private and public uses, and often devotes special attention to the relations among these different uses and dimensions. Recurring themes in technocritical discourse include the deconstruction of essentialist concepts such as "health", "human", "nature" or "norm".
Technocritical theory can be either "descriptive" or "prescriptive" in tone. Descriptive forms of technocriticism include some scholarship in the history of technology, science and technology studies, cyberculture studies and philosophy of technology. More prescriptive forms of technocriticism can be found in the various branches of technoethics, for example, media criticism, infoethics, bioethics, neuroethics, roboethics, nanoethics, existential risk assessment and some versions of environmental ethics and environmental design theory.
Figures engaged in technocritical scholarship and theory include Donna Haraway and Bruno Latour (who work in the closely related field of science studies), N. Katherine Hayles (who works in the field of Literature and Science), Phil Agree and Mark Poster (who works in intellectual history), Marshall McLuhan and Friedrich Kittler (who work in the closely related field of media studies), Susan Squier and Richard Doyle (who work in the closely related field of medical sociology), and Hannah Arendt, Walter Benjamin, Martin Heidegger, and Michel Foucault (who sometimes wrote about the philosophy of technology). Technocriticism can be juxtaposed with a number of other innovative interdisciplinary areas of scholarship which have surfaced in recent years such as technoscience and technoethics.
What is Relief printing?
Relief printing is a family of printing methods where a printing block, plate or matrix that has had ink applied to its surface, but not to any recessed areas, is brought into contact with paper. The areas of the printing plate with ink will leave ink on the paper, whereas the recessed areas of the printing plate will leave the paper ink-free. A printing press may not be needed, as the back of the paper can be rubbed or pressed by hand with a simple tool such as a brayer or roller.
In many historical processes, the matrix in relief printing is created by starting with a flat original surface and then removing (e.g., by carving) away areas intended to print white. The remaining areas of the original surface receive the ink. The relief family of techniques includes woodcut, metalcut, wood engraving, relief etching, linocut, rubber stamp, foam printing, potato printing, and some types of collagraph.
Traditional text printing with movable type is also a relief technique. This meant that woodcuts were much easier to use as book illustrations, as they could be printed together with the text. Intaglio illustrations, such as engravings, had to be printed separately.
Relief printing is one of the traditional families of printmaking techniques, along with the intaglio and planographic families. Modern developments have created other types. In contrast, in the intaglio process the recessed areas are the printed areas. The whole matrix is inked, and the ink then wiped away from the surface, so that it remains only in the recesses. Much greater pressure is then needed to force the paper into the channels containing the ink, and a high-pressure press will normally be required. Intaglio techniques include engraving, etching, and drypoint. With planographic techniques, such as lithography, the entire surface of the matrix is flat, and some areas are treated to create the print image.
Normally, relief and intaglio techniques can only be mixed with others of the same family in the same printed page, unless the page is printed twice.
In many historical processes, the matrix in relief printing is created by starting with a flat original surface and then removing (e.g., by carving) away areas intended to print white. The remaining areas of the original surface receive the ink. The relief family of techniques includes woodcut, metalcut, wood engraving, relief etching, linocut, rubber stamp, foam printing, potato printing, and some types of collagraph.
Traditional text printing with movable type is also a relief technique. This meant that woodcuts were much easier to use as book illustrations, as they could be printed together with the text. Intaglio illustrations, such as engravings, had to be printed separately.
Relief printing is one of the traditional families of printmaking techniques, along with the intaglio and planographic families. Modern developments have created other types. In contrast, in the intaglio process the recessed areas are the printed areas. The whole matrix is inked, and the ink then wiped away from the surface, so that it remains only in the recesses. Much greater pressure is then needed to force the paper into the channels containing the ink, and a high-pressure press will normally be required. Intaglio techniques include engraving, etching, and drypoint. With planographic techniques, such as lithography, the entire surface of the matrix is flat, and some areas are treated to create the print image.
Normally, relief and intaglio techniques can only be mixed with others of the same family in the same printed page, unless the page is printed twice.
What is Wood engraving?
Wood engraving is a printmaking and letterpress printing technique, in which an artist works an image or matrix of images into a block of wood. Functionally a variety of woodcut, it uses relief printing, where the artist applies ink to the face of the block and prints using relatively low pressure. By contrast, ordinary engraving, like etching, uses a metal plate for the matrix, and is printed by the intaglio method, where the ink fills the valleys, the removed areas. As a result, wood engravings deteriorate less quickly than copper-plate engravings, and have a distinctive white-on-black character.
Wood-engraved blocks could be used on conventional printing presses, which were going through rapid mechanical improvements during the first quarter of the 19th century. The blocks were made the same height as, and composited alongside, movable type in page layouts—so printers could produce thousands of copies of illustrated pages with almost no deterioration. The combination of this new wood engraving method and mechanized printing drove a rapid expansion of illustrations in the 19th century. Further, advances in stereotype let wood-engravings be reproduced onto metal, where they could be mass-produced for sale to printers.
Technique
A dark wooden block at an angle
This original wood block by Thomas Bewick is made to type height so it could be used in a letterpress.
A dark wooden block from above
The block shown from above. Notice the circular area marking damaged and repaired wood on the left next to the figure of a man.
A print made from the block
A print made from the block. The repaired circular area is visible on the right between the man and the dog.
Wood engraving blocks are typically made of boxwood or other hardwoods such as lemonwood or cherry. They are expensive to purchase because end-grain wood must be a section through the trunk or large bough of a tree. Some modern wood engravers use substitutes made of PVC or resin, mounted on MDF, which produce similarly detailed results of a slightly different character.
The block is manipulated on a "sandbag" (a sand-filled circular leather cushion). This helps the engraver produce curved or undulating lines with minimal manipulation of the cutting tool.
Wood engravers use a range of specialized tools. The lozenge graver is similar to the burin used by copper engravers of Bewick's day, and comes in different sizes. Various sizes of V-shaped graver are used for hatching. Other, more flexible, tools include the spitsticker, for fine undulating lines; the round scorper for curved textures; and the flat scorper for clearing larger areas.
Wood engraving is generally a black-and-white technique. However, a handful of wood engravers also work in colour, using three or four blocks of primary colours—in a way parallel to the four-colour process in modern printing. To do this, the printmaker must register the blocks (make sure they print in exactly the same place on the page). Recently, engravers have begun to use lasers to engrave wood.
Wood-engraved blocks could be used on conventional printing presses, which were going through rapid mechanical improvements during the first quarter of the 19th century. The blocks were made the same height as, and composited alongside, movable type in page layouts—so printers could produce thousands of copies of illustrated pages with almost no deterioration. The combination of this new wood engraving method and mechanized printing drove a rapid expansion of illustrations in the 19th century. Further, advances in stereotype let wood-engravings be reproduced onto metal, where they could be mass-produced for sale to printers.
Technique
A dark wooden block at an angle
This original wood block by Thomas Bewick is made to type height so it could be used in a letterpress.
A dark wooden block from above
The block shown from above. Notice the circular area marking damaged and repaired wood on the left next to the figure of a man.
A print made from the block
A print made from the block. The repaired circular area is visible on the right between the man and the dog.
Wood engraving blocks are typically made of boxwood or other hardwoods such as lemonwood or cherry. They are expensive to purchase because end-grain wood must be a section through the trunk or large bough of a tree. Some modern wood engravers use substitutes made of PVC or resin, mounted on MDF, which produce similarly detailed results of a slightly different character.
The block is manipulated on a "sandbag" (a sand-filled circular leather cushion). This helps the engraver produce curved or undulating lines with minimal manipulation of the cutting tool.
Wood engravers use a range of specialized tools. The lozenge graver is similar to the burin used by copper engravers of Bewick's day, and comes in different sizes. Various sizes of V-shaped graver are used for hatching. Other, more flexible, tools include the spitsticker, for fine undulating lines; the round scorper for curved textures; and the flat scorper for clearing larger areas.
Wood engraving is generally a black-and-white technique. However, a handful of wood engravers also work in colour, using three or four blocks of primary colours—in a way parallel to the four-colour process in modern printing. To do this, the printmaker must register the blocks (make sure they print in exactly the same place on the page). Recently, engravers have begun to use lasers to engrave wood.
What is Sideloading?
Sideloading is a term used mostly on the Internet, similar to "upload" and "download", but in reference to the process of transferring files between two local devices, in particular between a computer and a mobile device such as a mobile phone, smartphone, PDA, tablet, portable media player or e-reader.
Sideloading typically refers to media file transfer to a mobile device via USB, Bluetooth, WiFi or by writing to a memory card for insertion into the mobile device.
When referring to Android apps, "sideloading" typically means installing an application package in APK format onto an Android device. Such packages are usually downloaded from websites other than Google play, usually through a computer. For Android users sideloading of apps is only possible if the user has allowed "Unknown Sources" in their Security Settings.
When referring to iOS apps, "sideloading" means installing an app in IPA format onto an Apple Device, usually through the use of a computer program such as Cydia Impactor, Xcode, on the actual device using a Jailbreak method or using a signing service instead of through Apple's App Store. On modern versions of iOS, the sources of the apps must be trusted by both Apple and the user in "profiles and device management" in settings; except when using jailbreak methods of sideloading apps.
Advantages
There are no wireless data charges. Sideloading delivery does not involve a wireless carrier.
Content can be optimized for each mobile device. As there are no mobile network restrictions, content can be tailored for each device. This is more important for video playback, where the lowest common denominator is often a limiting factor on wireless networks.
There are no geographic limitations on the delivery of content for sideloading as are implicit in the limited coverage of wireless networks.
There are no restrictions on what content can be sideloaded. Users may sideload video, e-books, or software which is restricted or banned in their country, including material expressing unpopular or illegal opinions, and, of course, pornography.
The content is not streamed, and can be permanently stored in the mobile device. It can be listened to or watched at the user’s convenience.
Side-loading is an excellent mechanism for proximity marketing.
Disadvantages
Streaming media is sometimes preferred to downloading due to limited storage. Content providers limit content available to download and side-load due to their loss of control over it.
There are huge variations in performance capability for mobile devices that can make use of sideloading, from simple mobile phones with limited video playback, to high-end portable media players. Unless the audio/video file is encoded with the target device in mind, playback may not be possible.
Some wireless carriers (most notably Verizon Wireless) require that handset manufacturers limit the sideload capabilities of devices on their networks as a form of vendor lock-in. This usually results in the loss of USB and Bluetooth as sideload options (though memory card transfer is still available).
Methods
Bluetooth sideloading
Bluetooth’s OBEX/OPP profiles allow for file transfer between a PC and a mobile device. Using this option is slightly more complicated than using a USB connection as the two devices have to be paired first. Also, unlike the familiar drag and drop that is usually available via USB, Bluetooth implementation is specific to the Bluetooth transceiver and drivers being used. Files that are sideloaded to mobile devices via Bluetooth are often received as messages, in the same way that SMS texts would be received. While these files can be saved to any storage medium, their initial location is the handset’s internal memory. As such the limitations of the internal memory have to be taken into account before beginning the sideload.
Memory card sideloading
Sideloading via a memory card requires that the user have access to a memory card writer. This should not be a problem as memory card reader/writers can often be purchased in a computer store for under USD$10, or purchased online for $5 or less. Audio and video files can be written directly to the memory card and then inserted into the mobile device. This is potentially the quickest way of sideloading several files at once, as long as the user knows where to put the media files.
Sideloading typically refers to media file transfer to a mobile device via USB, Bluetooth, WiFi or by writing to a memory card for insertion into the mobile device.
When referring to Android apps, "sideloading" typically means installing an application package in APK format onto an Android device. Such packages are usually downloaded from websites other than Google play, usually through a computer. For Android users sideloading of apps is only possible if the user has allowed "Unknown Sources" in their Security Settings.
When referring to iOS apps, "sideloading" means installing an app in IPA format onto an Apple Device, usually through the use of a computer program such as Cydia Impactor, Xcode, on the actual device using a Jailbreak method or using a signing service instead of through Apple's App Store. On modern versions of iOS, the sources of the apps must be trusted by both Apple and the user in "profiles and device management" in settings; except when using jailbreak methods of sideloading apps.
Advantages
There are no wireless data charges. Sideloading delivery does not involve a wireless carrier.
Content can be optimized for each mobile device. As there are no mobile network restrictions, content can be tailored for each device. This is more important for video playback, where the lowest common denominator is often a limiting factor on wireless networks.
There are no geographic limitations on the delivery of content for sideloading as are implicit in the limited coverage of wireless networks.
There are no restrictions on what content can be sideloaded. Users may sideload video, e-books, or software which is restricted or banned in their country, including material expressing unpopular or illegal opinions, and, of course, pornography.
The content is not streamed, and can be permanently stored in the mobile device. It can be listened to or watched at the user’s convenience.
Side-loading is an excellent mechanism for proximity marketing.
Disadvantages
Streaming media is sometimes preferred to downloading due to limited storage. Content providers limit content available to download and side-load due to their loss of control over it.
There are huge variations in performance capability for mobile devices that can make use of sideloading, from simple mobile phones with limited video playback, to high-end portable media players. Unless the audio/video file is encoded with the target device in mind, playback may not be possible.
Some wireless carriers (most notably Verizon Wireless) require that handset manufacturers limit the sideload capabilities of devices on their networks as a form of vendor lock-in. This usually results in the loss of USB and Bluetooth as sideload options (though memory card transfer is still available).
Methods
Bluetooth sideloading
Bluetooth’s OBEX/OPP profiles allow for file transfer between a PC and a mobile device. Using this option is slightly more complicated than using a USB connection as the two devices have to be paired first. Also, unlike the familiar drag and drop that is usually available via USB, Bluetooth implementation is specific to the Bluetooth transceiver and drivers being used. Files that are sideloaded to mobile devices via Bluetooth are often received as messages, in the same way that SMS texts would be received. While these files can be saved to any storage medium, their initial location is the handset’s internal memory. As such the limitations of the internal memory have to be taken into account before beginning the sideload.
Memory card sideloading
Sideloading via a memory card requires that the user have access to a memory card writer. This should not be a problem as memory card reader/writers can often be purchased in a computer store for under USD$10, or purchased online for $5 or less. Audio and video files can be written directly to the memory card and then inserted into the mobile device. This is potentially the quickest way of sideloading several files at once, as long as the user knows where to put the media files.
Wednesday, January 8, 2020
What is Lineman's pliers? and How to use it?
Lineman's pliers (US English), Kleins (generic trademark, US usage), linesman pliers (Canadian English)[citation needed] and combination pliers (UK / US English), or simply pliers (since other versions are more commonly discombobulated with a prefix, such as "needle-nose", etc) are a type of pliers used by linemen, electrical contractors and other tradesmen primarily for gripping, twisting, bending and cutting wire, cable and small metalwork components. They owe their effectiveness to their pliers design, which multiplies force through leverage.
Lineman's pliers are distinguished by a flat gripping surface at their snub nose. Combination pliers have a shorter flat surface plus a concave / curved gripping surface which is useful in light engineering to work with metal bar, etc. Both usually have a beveled cutting edge similar to that on Diagonal pliers in their craw, and each may include an additional gripping, crimping, or wire shearing (for a flat ended cut) device at the crux of the handle side of the pliers' joint.
Designed for potentially heavy manual operation, these pliers typically are machined from forged steel and the two handles precisely joined with a heavy-duty rivet that maintains the pliers' accuracy even after repeated use under extreme force on heavy-gauge wire. They usually have grips for better handling than bare metal handles; the grips may also provide insulation for protection against electric shock when working with live circuits, although most models are marked as not listed for such use. Some pliers are certified to withstand a specified voltage, e.g. 1000 V.
Typical uses
Lineman's pliers are used in the electrical trade to cut, straighten, and bend wire, and also to twist wires together when making splices. Lineman's can be used to strip wire and some types of cable, although wire strippers are more commonly used for this purpose as they can strip wire more quickly without damaging the conductors themselves. They can also be used to pull fish tape through long runs of conduit where the high friction makes it difficult to pull it by hand. Some pliers are equipped with a crimping tool for the purpose of compressing crimp connections.
Lineman's pliers can be used to bend or straighten sheet metal components, especially in cases where smaller pliers don't offer enough mechanical advantage. The square nose and flat side of Lineman pliers is particularly useful for creating accurate right angle bends. The durability of these pliers allows them to be used for tasks like removing nails and other types of fasteners.
Lineman's pliers are similar to needle-nose pliers: both tools share a typically solid, machined forged steel construction, durable pivot, gripping nose and cutting craw. The main differences are that the slender nose of the needle-nose pliers enable it to form small diameter bends, and position or support items in awkward places. Needle-nose pliers typically have a lower handle/nose length ratio, reducing the force that can be exerted at the tip. Also, needle-nose pliers tend to be available in smaller sizes (for electronics applications, they may be found as small as 1/10 scale of the full-size version).
Lineman's pliers may be used to cut steel screws up to #10, and virtually any dry-wall screw, although the thread form will be distorted. Lineman's pliers sometimes include an integrated crimping device in the craw of the handle side of the pliers' joint.
Lineman's pliers have a tapered nose suitable for reaming the rough edge of a 1/2" or larger conduit, or cleaning sharp metal from the inside of a standard metal knockout in an electrical enclosure such as a junction box or breaker panel. Some brands manufacture pliers (i.e. Ideal) with a narrower jaw, suitable for reaming smaller conduit.
Lineman's pliers are distinguished by a flat gripping surface at their snub nose. Combination pliers have a shorter flat surface plus a concave / curved gripping surface which is useful in light engineering to work with metal bar, etc. Both usually have a beveled cutting edge similar to that on Diagonal pliers in their craw, and each may include an additional gripping, crimping, or wire shearing (for a flat ended cut) device at the crux of the handle side of the pliers' joint.
Designed for potentially heavy manual operation, these pliers typically are machined from forged steel and the two handles precisely joined with a heavy-duty rivet that maintains the pliers' accuracy even after repeated use under extreme force on heavy-gauge wire. They usually have grips for better handling than bare metal handles; the grips may also provide insulation for protection against electric shock when working with live circuits, although most models are marked as not listed for such use. Some pliers are certified to withstand a specified voltage, e.g. 1000 V.
Typical uses
Lineman's pliers are used in the electrical trade to cut, straighten, and bend wire, and also to twist wires together when making splices. Lineman's can be used to strip wire and some types of cable, although wire strippers are more commonly used for this purpose as they can strip wire more quickly without damaging the conductors themselves. They can also be used to pull fish tape through long runs of conduit where the high friction makes it difficult to pull it by hand. Some pliers are equipped with a crimping tool for the purpose of compressing crimp connections.
Lineman's pliers can be used to bend or straighten sheet metal components, especially in cases where smaller pliers don't offer enough mechanical advantage. The square nose and flat side of Lineman pliers is particularly useful for creating accurate right angle bends. The durability of these pliers allows them to be used for tasks like removing nails and other types of fasteners.
Lineman's pliers are similar to needle-nose pliers: both tools share a typically solid, machined forged steel construction, durable pivot, gripping nose and cutting craw. The main differences are that the slender nose of the needle-nose pliers enable it to form small diameter bends, and position or support items in awkward places. Needle-nose pliers typically have a lower handle/nose length ratio, reducing the force that can be exerted at the tip. Also, needle-nose pliers tend to be available in smaller sizes (for electronics applications, they may be found as small as 1/10 scale of the full-size version).
Lineman's pliers may be used to cut steel screws up to #10, and virtually any dry-wall screw, although the thread form will be distorted. Lineman's pliers sometimes include an integrated crimping device in the craw of the handle side of the pliers' joint.
Lineman's pliers have a tapered nose suitable for reaming the rough edge of a 1/2" or larger conduit, or cleaning sharp metal from the inside of a standard metal knockout in an electrical enclosure such as a junction box or breaker panel. Some brands manufacture pliers (i.e. Ideal) with a narrower jaw, suitable for reaming smaller conduit.
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