HOW TO DETECT BLOOD OR BODILY FLUIDS USING UV LIGHT 1.For Luminol: It's sprayed at a scene (in the dark) and then H2O2 is sprayed after it (this is to see whether false positives may be catalyzing the rxn which results in the characteristic chemiluminescence seen). No extra light source is necessary. 1.For UV light: If one wants to use UV light to illuminate a blood pattern, this is more difficult. Blood under UV light absorbs light and does NOT glow. However, it is possible to visualize a blood pattern under UV light if the surrounding medium does fluoresce under UV lighting. WHY WEAR GOGGLES The filters are sort of like 'Blue Blockers', blocking the visible part of NEAR UV emissions. This will make items that only floresce very slightly more visible since they are no longer overpowered by the blue light emitted in the visible part of the spectrum. CSI PRODUCTS Use these UV (Ultraviolet) lights for close examination of the crime scene to reveal evidence not visible under normal lighting to the naked eye. Evidence can't hide from UV light. UV lights reveal hidden blood, fingerprints, fibers, and subcutaneous bruises on living and dead bodies. Orange viewing goggles are sometimes used with UV lights to enhance the contrast of fluorescent fingerprint powder and to visualize fibers and body fluids. You can add orange goggles by selecting them from the pulldown menu beneath the product photo on this page. This light is available in three wavelengths: •Blue 400nm (21 LED) •Standard 385nm (9 LED) •Invisible 365nm (5 Nichia LED) DEMO IDEA YIKES!!! I just dug up my yellow shooting specs and fired up the UV LED light in the laundry room. Month ago I dropped a full 3 gallon jug of liquid laundry detergent and when it hit the floor it ruptured almost explosively spewing liquid all over. Blue Light This blue 460 nm LED flashlight shines in the 460nm range. It is useful to help identify Trace Evidence, Gun Shot Residue and Blood Spatter. It can... THERMAL IMAGING Types of Thermal Imaging Devices Most thermal-imaging devices scan at a rate of 30 times per second. They can sense temperatures ranging from -4 degrees Fahrenheit (-20 degrees Celsius) to 3,600 F (2,000 C), and can normally detect changes in temperature of about 0.4 F (0.2 C). There are two common types of thermal-imaging devices: •Un-cooled - This is the most common type of thermal-imaging device. The infrared-detector elements are contained in a unit that operates at room temperature. This type of system is completely quiet, activates immediately and has the battery built right in. •Cryogenically cooled - More expensive and more susceptible to damage from rugged use, these systems have the elements sealed inside a container that cools them to below 32 F (zero C). The advantage of such a system is the incredible resolution and sensitivity that result from cooling the elements. Cryogenically-cooled systems can "see" a difference as small as 0.2 F (0.1 C) from more than 1,000 ft (300 m) away, which is enough to tell if a person is holding a gun at that distance! While thermal imaging is great for detecting people or working in near-absolute darkness, most night-vision equipment uses image-enhancement technology. In order to understand night vision, it is important to understand something about light. The amount of energy in a light wave is related to its wavelength: Shorter wavelengths have higher energy. Of visible light, violet has the most energy, and red has the least. Just next to the visible light spectrum is the infrared spectrum. Infrared light can be split into three categories: •Near-infrared (near-IR) - Closest to visible light, near-IR has wavelengths that range from 0.7 to 1.3 microns, or 700 billionths to 1,300 billionths of a meter. •Mid-infrared (mid-IR) - Mid-IR has wavelengths ranging from 1.3 to 3 microns. Both near-IR and mid-IR are used by a variety of electronic devices, including remote controls. •Thermal-infrared (thermal-IR) - Occupying the largest part of the infrared spectrum, thermal-IR has wavelengths ranging from 3 microns to over 30 microns. The key difference between thermal-IR and the other two is that thermal-IR is emitted by an object instead of reflected off it. Infrared light is emitted by an object because of what is happening at the atomic level. How Night Vision Works Image-enhancement technology is what most people think of when you talk about night vision. In fact, imageenhancement systems are normally called night-vision devices (NVDs). NVDs rely on a special tube, called an imageintensifier tube, to collect and amplify infrared and visible light 1.A conventional lens, called the objective lens, captures ambient light and some near-infrared light. 2.The gathered light is sent to the image-intensifier tube. In most NVDs, the power supply for the image-intensifier tube receives power from two N-Cell or two "AA" batteries. The tube outputs a high voltage, about 5,000 volts, to the image-tube components. 3.The image-intensifier tube has a photocathode, which is used to convert the photons of light energy into electrons. GAMM RAYS - Radiation Sickness Radiation is pretty scary stuff. You usually can't see, smell or taste it, and you can only detect it reliably with special devices that few people have lying around the house. Yet, we constantly hear that radiation causes a wide range of harmful effects, from cancer and sterility to severe burns. One of radiation's more horrifying effects is commonly known as radiation sickness. Radiation sickness is an umbrella term for the damage caused by a large, acute dose of radiation. In fact, the technical term for radiation sickness is acute radiation syndrome. You might also hear it referred to as radiation poisoning. While both acute, short term radiation exposure and long-term radiation exposure can lead to cancer due to DNA damage, cancer caused by radiation is not radiation sickness. Radiation is both natural and man-made. Our bodies are exposed to natural radiation every day -- from soil and underground gases to cosmic radiation from the sun and outer space. We're also exposed to radiation from our own inventions -- medical procedures, televisions, cell phones and microwave ovens. Radiation isn't necessarily always dangerous. It depends on its strength, type and the length of exposure. Most types of radiation are harmless; even the dangerous kinds won't cause radiation sickness unless you receive a large dose. In fact, any type of emitted energy is basically radiation, like the radio waves picked up by your car stereo, the heat given off by your toaster -- even the light given off by the sun. The kind of radiation that causes radiation sickness is called ionizing radiation. Ionizing radiation has a higher energy and higher frequency; this group includes ultraviolet, xray and gamma ray energy. As its name indicates, it's powerful enough to ionize -- that is, to knock an electron away from any atom it hits. In fact, ionizing radiation can even destroy an atom's nucleus. Beta particles are electrons that move very quickly -- that is, with a lot of energy. Beta particles travel several feet when emitted from a radioactive source, but they're blocked by most solid objects. A beta particle is about 8,000 times smaller than an alpha particle -- and that's what makes them more dangerous. Their small size allows them to penetrate clothing and skin. External exposure can cause burns and tissue damage, along with other symptoms of radiation sickness. If radioactive material enters food or water supplies or is dispersed into the air, people can inhale or ingest beta particle emitters unknowingly. Internal exposure to beta particles causes much more severe symptoms than external exposure. Gamma rays are the most dangerous form of ionizing radiation. These extremely high energy photons can travel through most forms of matter because they have no mass. It takes several inches of lead -- or several feet of concrete -- to effectively block gamma rays. If you're exposed to gamma rays, they pass through your entire body, affecting all of your tissues from your skin to the marrow of your bones. This causes widespread, systemic damage. When we talk about the amount of radiation needed to trigger a certain set of radiation sickness symptoms, we're not talking in terms of absolute amounts. Instead, we're talking about the total dosage. A burst dose of 0.75 Sv can be enough to induce radiation sickness, including nausea and a weakened immune system. Three sieverts will cause more severe effects, but usually won't be fatal if you receive medical care. An instantaneous dose of 10 or more sieverts will be fatal, even with medical care. A dose somewhere in between gives you a roughly 50 percent chance of dying within 30 days. Radiation sickness initially manifests with symptoms within a few minutes or hours of exposure; these symptoms include nausea, diarrhea, headache, fever and even, in severe cases, loss of consciousness. High doses also cause burns on the skin. Symptoms occur more quickly the greater the dose of radiation, and will fade in one or two days. Following that is a latent period, a lull during which there are no symptoms. The radiation damages cells and structures within the body. Most vulnerable is bone marrow, where stem cells produce blood cells. CAT SCANS CAT scans take the idea of conventional X-ray imaging to a new level. Instead of finding the outline of bones and organs, a CAT scan machine forms a full three-dimensional computer model of a patient's insides. Doctors can even examine the body one narrow slice at a time to pinpoint specific areas. Computerized axial tomography (CAT) scan machines produce X-rays, a powerful form of electromagnetic energy. X-ray photons are basically the same thing as visible light photons, but they have much more energy. This higher energy level allows X-ray beams to pass straight through most of the soft material in the human body. A conventional X-ray image is basically a shadow: You shine a "light" on one side of the body, and a piece of film on the other side registers the silhouette of the bones. Shadows give you an incomplete picture of an object's shape. Imagine you are standing in front of a wall, holding a pineapple against your chest with your right hand and a banana out to your side with your left hand. Your friend is looking only at the wall, not at you. If there's a lamp in front of you, your friend will see the outline of you holding the banana, but not the pineapple -- the shadow of your torso blocks the pineapple. If the lamp is to your left, your friend will see the outline of the pineapple, but not the banana. The same thing happens in a conventional X-ray image. If a larger bone is directly between the X-ray machine and a smaller bone, the larger bone may cover the smaller bone on the film. In order to see the smaller bone, you would have to turn your body or move the X-ray machine. In order to know that you are holding a pineapple and a banana, your friend would have to see your shadow in both positions and form a complete mental image. This is the basic idea of computer aided tomography. In a CAT scan machine, the X-ray beam moves all around the patient, scanning from hundreds of different angles. The computer takes all this information and puts together a 3-D image of the body. The CAT machine looks like a giant doughnut tipped on its side. The patient lies down on a platform, which slowly moves through the hole in the machine. The X-ray tube is mounted on a movable ring around the edges of the hole. The ring also supports an array of X-ray detectors directly opposite the X-ray tube. A motor turns the ring so that the X-ray tube and the X-ray detectors revolve around the body. Each full revolution scans a narrow, horizontal "slice" of the body. The control system moves the platform farther into the hole so the tube and detectors can scan the next slice. In this way, the machine records X-ray slices across the body in a spiral motion. The computer varies the intensity of the X-rays in order to scan each type of tissue with the optimum power. After the patient passes through the machine, the computer combines all the information from each scan to form a detailed image of the body. It's not usually necessary to scan the entire body, of course. More often, doctors will scan only a small section. Since they examine the body slice by slice, from all angles, CAT scans are much more comprehensive than conventional X-rays. Today, doctors use CAT scans to diagnose and treat a wide variety of ailments, including head trauma, cancer and osteoporosis. They are an invaluable tool in modern medicine. UNIVERSAL REMOTES Pros - Powerful. Easy to set up. Bluetooth and app support make the remote even more flexible. Cons - Very expensive. Bottom Line - If you can get past the price tag, the Logitech Harmony Ultimate is the most powerful, simplest universal remote you can get. Design The Harmony Ultimate$349.99 at Crutchfield.com remote itself looks and feels almost identical to the Harmony Touch. It's still a conventionally shaped remote control centered around a large 2.4-inch touch screen flanked by large, simple buttons for playback, navigation, and volume/channel control. The controller has a matte, textured underside that feels both sturdy and secure in the hand, and its slim, curved profile is much more comfortable than many chunkier, rectangular remotes. It has a micro USB port hidden behind a rubber door on the bottom, and two metal contacts let it charge in the included cradle Bluetooth Bluetooth support means the Harmony Ultimate controls not only your HDTV, Blu-ray player, and set-top box, but your game systems as well. A simple Bluetooth wizard guides you through pairing the remote with the Sony PlayStation 3 and Nintendo Wii U. SET UP Setup is easy, and identical to the Harmony Touch's setup process. Logitech's Harmony Web site has a simple Web app that configures all current programmable Harmony remotes over a USB connection with the included micro USB cable. It asks for the brand and model number of your home entertainment devices, then automatically adds them to the remote, with all control support included. You can then set up activities like watching television or watching a Bluray disc. After you enter which devices you use for which activity, the app automatically generates the correct series of commands to send out and which devices to make active during that activity. Sony Navitus RM-NX7000 If you want to take a crack at programming a high-end remote to make it do exactly what you want, consider the Sony Navitus RM-NX7000. Sony recommends setup by an A/V installer. The wedge-shaped Navitus—6.5 by 4 by 2 inches (HWD)—has a horizontal, 3.5-inch QVGA screen that gives tactile feedback (thanks to a technology called TouchEngine) when you press an on-screen button. All the controls are on top rather than on the side, and five direct-access buttons take you to specific pages. On the downside, most of the 19 buttons are brushed chrome and hard to read in dim light. This is an IR-only remote, not RF, so you can't turn down the volume from two rooms over. Aesthetically, the RM-NX7000 is a bit blocky; some may prefer something sleeker, such as the NevoSL. With this model, Sony may be caught being too high-end (price) and not high-end enough (no RF). If you're a one-room user, though, this remote may suit you just fine. Fobis weemote 3 Simple is good, but simple plus cheap is better. At $24.95, the weemote 3 fills the bill perfectly. This limited-function remote has nine big buttons with different colors and shapes. Programming controls and batteries are behind no-kidsallowed, screw-protected panels. It's not a universal remote, but the weemote can switch the TV to an input for a VCR or DVD player via one of the five Favorites buttons. You can associate a favorite channel with the power-on button and lock out others. For control of DVD players, you may want to add the separate weemote DV ($19.95). Adults who like simplicity can opt for the color-neutral weemote Sr. (also $24.95), but you'll lose functions like picture-in-picture.
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