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Universal asynchronous receiver-transmitter

A universal asynchronous receiver-transmitter is a computer hardware device for asynchronous serial communication in which the data format and transmission speeds are configurable. The electric signaling levels and methods are handled by a driver circuit external to the UART. A UART is an individual integrated circuit used for serial communications over a computer or peripheral device serial port. One or more UART peripherals are integrated in microcontroller chips. A related device, the universal synchronous and asynchronous receiver-transmitter supports synchronous operation; the universal asynchronous receiver-transmitter takes bytes of data and transmits the individual bits in a sequential fashion. At the destination, a second UART re-assembles the bits into complete bytes; each UART contains a shift register, the fundamental method of conversion between serial and parallel forms. Serial transmission of digital information through a single wire or other medium is less costly than parallel transmission through multiple wires.

The UART does not directly generate or receive the external signals used between different items of equipment. Separate interface devices are used to convert the logic level signals of the UART to and from the external signalling levels, which may be standardized voltage levels, current levels, or other signals. Communication may be simplex, full half duplex; the idle, no data state is high-voltage, or powered. This is a historic legacy from telegraphy, in which the line is held high to show that the line and transmitter are not damaged; each character is framed as a logic low start bit, data bits a parity bit and one or more stop bits. In most applications the least significant data bit is transmitted first; the start bit signals the receiver. The next five to nine bits, depending on the code set employed, represent the character. If a parity bit is used, it would be placed after all of the data bits; the next one or two bits called the stop bit. They signal to the receiver. Since the start bit is logic low and the stop bit is logic high there are always at least two guaranteed signal changes between characters.

If the line is held in the logic low condition for longer than a character time, this is a break condition that can be detected by the UART. All operations of the UART hardware are controlled by an internal clock signal which runs at a multiple of the data rate 8 or 16 times the bit rate; the receiver tests the state of the incoming signal on each clock pulse, looking for the beginning of the start bit. If the apparent start bit lasts at least one-half of the bit time, it is valid and signals the start of a new character. If not, it is ignored. After waiting a further bit time, the state of the line is again sampled and the resulting level clocked into a shift register. After the required number of bit periods for the character length have elapsed, the contents of the shift register are made available to the receiving system; the UART will set a flag indicating new data is available, may generate a processor interrupt to request that the host processor transfers the received data. Communicating UARTs have no shared timing system apart from the communication signal.

UARTs resynchronize their internal clocks on each change of the data line, not considered a spurious pulse. Obtaining timing information in this manner, they reliably receive when the transmitter is sending at a different speed than it should. Simplistic UARTs do not do this, instead they resynchronize on the falling edge of the start bit only, read the center of each expected data bit, this system works if the broadcast data rate is accurate enough to allow the stop bits to be sampled reliably, it is a standard feature for a UART to store the most recent character while receiving the next. This "double buffering" gives a receiving computer an entire character transmission time to fetch a received character. Many UARTs have a small first-in, first-out buffer memory between the receiver shift register and the host system interface; this allows the host processor more time to handle an interrupt from the UART and prevents loss of received data at high rates. Transmission operation is simpler as the timing does not have to be determined from the line state, nor is it bound to any fixed timing intervals.

As soon as the sending system deposits a character in the shift register, the UART generates a start bit, shifts the required number of data bits out to the line and sends the parity bit, sends the stop bits. Since full-duplex operation requires characters to be sent and received at the same time, UARTs use two different shift registers for transmitted and received characters. High performance UARTs could contain a transmit FIFO buffer to allow a CPU or DMA controller to deposit multiple characters in a burst into the FIFO rather than have to deposit one character at a time into the FIFO. Since transmission of a single or multiple characters may take a long time relative to CPU speeds, a UART maintains a flag showing busy status so that the host system knows if there is at least one cha

Orange Mound Spring

Orange Mound Spring is one of the several hot springs in Yellowstone National Park. The name comes from its dark orange appearance caused by orange cyanobacteria living on the travertine, the rock that it is made of; the Orange Mound Spring is part of the Mammoth Hot Springs area of the park. The Orange Mound Spring is arguably most notable for its prominence above the ground, compared to the rest of the Mammoth Hot Springs, which are flat and leveled terraces; the Orange Mound Spring is thermally cooler than most springs in Yellowstone and at the Mammoth Hot Springs themselves, allowing the orange-tinted cyanobacteria to thrive and color the spring a darker shade of orange than the rest of the Mammoth Terraces. Depending on the nutrients that the bacteria receive, the color may change throughout the year; the Spring is said to be old due to the shape and size of the mound as well as how little water flows out of the spring itself. It has created other nearby cone-shaped springs from itself due to the travertine deposits wearing away.

In the Mammoth Hot Springs, flow will turn on and off, so on some days it may have no flow at all, others it may have a lot

Albanians in Belgium

Albanians number up to 60,000 people in Belgium. The vast majority emigrated from Republic of Macedonia and Albania. On August 1, 1956, the train carrying 700 refugees from southeastern European communist countries arrived at the Seille station in Namur province; these refugees among them were hundreds of refugees from Albania. This marks the first wave of Albanian exiles in Belgium; the first wave of Albanian exiles was so-called "elite". The emigrants came from northern Albania, were educated and opposed the communist dictatorship of Enver Hoxha seeking freedom. Albanian political refugees have been adapted well. In v. 1968 Skanderbeg Monument was built in Schaerbeek, with money collected from Albanian Diaspora in Belgium and America. In the 1960s, with immigrants from Turkey, who had migrated from Yugoslavia to Turkey, came to Belgium, they were strengthened in the 1980s. This first wave of exiles will be followed by the large influx of Kosovo Albanians beginning in the late 1970s and intensified in the 1990s as a result of Serbian repression over Kosovo Albanians.

This influx will culminate when Belgrade will massacre over thousands of Albanian civilians and drive out nearly a million Kosovo Albanians in v. In the 1990s, a second wave of exiles came from Albania after the collapse of the communist regime. Hundreds of thousands of Albanians, disconnected from the world for 45 years, fleeing poverty in Albania, rush to Italy and Greece, but to Belgium. In addition to Albanian citizens, there are numerous Albanians from Kosovo, Republic of Macedonia, Greece or Montenegro. Therefore, it is difficult to give an exact number of ethnic Albanian people in a Western European country. In the Brussels region alone, around 40,000 Albanians live, most of them in Schaerbeek. Krenar Gashi - Political scientist Adnan Januzaj - Belgian professional footballer who plays as a winger for Spanish club Real Sociedad and the Belgium national team Lindon Selahi - Albanian professional footballer Zymer Bytyqi - Kosovar footballer Adrian Bakalli - Belgian former professional footballer Medjon Hoxha - Belgian professional footballer Rustemi Kreshnik - Albanian-Belgian kickboxer Sebastjan Spahiu - professional footballer Din Sula - professional footballer Emir Ujkani - Kosovar football goalkeeper Samir Ujkani - Kosovar goalkeeper Florian Loshaj - Belgian professional footballer Bleri Lleshi - Albanian philosopher and public speaker

Mitochondrial uncoupling protein 4

Mitochondrial uncoupling protein 4 is a protein that in humans is encoded by the SLC25A27 gene. Mitochondrial uncoupling proteins are members of the larger family of mitochondrial anion carrier proteins. UCPs separate oxidative phosphorylation from ATP synthesis with energy dissipated as heat referred to as the mitochondrial proton leak. UCPs facilitate the transfer of anions from the inner to the outer mitochondrial membrane and the return transfer of protons from the outer to the inner mitochondrial membrane, they reduce the mitochondrial membrane potential in mammalian cells. Tissue specificity occurs for the different UCPs and the exact methods of how UCPs transfer H+/OH- are not known. UCPs contain the three homologous protein domains of MACPs. Transcripts of this gene are detected only in brain tissue and are modulated by various environmental conditions; the proton transport activity of UCP4 has been shown to be activated by fatty acids and inhibited by purine nucleotides. In addition, reconstituted UCP4 exhibited a distinct conformation, compared to other UCPs in the family.

Solute carrier family Uncoupling protein This article incorporates text from the United States National Library of Medicine, in the public domain

MABEL (robot)

MABEL is a robot engineered in 2009 by researchers at the University of Michigan, well known for being the world's fastest bipedal robot with knees. MABEL is able to reach speeds of up to 3.6 m/s. The name MABEL is an acronym for Michigan Anthropomorphic Biped With Electronic Legs; the creators include J. W. Grizzle, Jonathan Hurst, Hae-Won Park, Koushil Sreenath, Alireza Ramezani. MABEL weighs 143 pounds with most of its weight being in the top torso area; the legs are jointed to form knees. The robot is attached to a safety boom for lateral stability. Create a robot similar to that of “the RABBIT”, but with certain modifications. Make a robot that can run fast, adapt to terrain, use energy efficiently. Innovate efficient powertrain and control feedback mechanisms. Promote outreach for University of Michigan College of Engineering. Spring: The hip and knee joints each contain a spring, connected in series with two motors. Point feet: The end of MABEL's legs have a point at the bottom so the foot hits the ground uniformly each time.

Safety Boom: A large metal pole that acts to stabilize. Since MABEL works in 2D, it would fall sideways without the boom. Safety Cable: A thin rope attached to the left midsection of MABEL to insure the robot doesn't fall; this was added. In order to make MABEL functional for extended periods of time, the researchers focused on ways to optimize powertrain efficiency. Unlike the RABBIT, MABEL was designed to have all four motors in the midsection instead of the legs; this makes the legs more agile. Secondly, most of MABEL’s power is stored in large springs that act to reduce shock and store energy. MABEL uses a differential so that the spring can be grounded by the torso of the robot instead of directly connected in series with a motor; this allows the compression in the springs to better apply force. Another innovative aspect of the springs is that they are referred to as “unilateral” because they don’t extend past the rest length, causing undirected force. In order for MABEL to be an independent runner and walker on rough terrain, the engineers used QNX real-time computing and DAQ environment in order to create feedback control.

Feedback control feeds in different inputs to the system based on the information from sensors. The controller measures the output values via sensors and compares those values with the desired output; the difference between the measured output and the desired output values is what is called the "error signal". This signal is than used to change the input values of the system accordingly; this method of feedback control makes thousands of adjustments each second in order to stabilize the robot. Because of this system, MABEL is able to not only correct itself, but to react to inconsistencies in terrain; the MABEL robot became well known after a YouTube video, uploaded by u/MichiganEngineering, received over 450,000 views. MABEL was featured on a CNN segment on September 19, 2011, in which co-creator Prof. Jessy Grizzle was interviewed on live television. Up until August 2014, MABEL has been used for outreach during K-12 student tours of the College of Engineering at University of Michigan. On August 14, 2014, MABEL was put on display in the Chicago Field Museum where it resides.

In his interview with CNN, Jessy Grizzle stated that this kind of technology could be useful for firefighting situations in which firefighters believe no one is in a burning house but surveillance is necessary. In his interview, he added that the innovative control feedback algorithms could play a role in aiding paralyzed people, he said that the feedback algorithms would be necessary to engineer exoskeletons, mechanical systems that attach to the human body to aid muscle movements. Grizzle is collaborating with Jonathan Hurst from the Robotics Institute at Carnegie Mellon to create a new bipedal robot named "MARLO". Instead of walking and running in 2D while connected to a boom, MARLO will move in 3D. A robot in 3D means that the robot would be free-standing without a safety safety cable. During testing in 2013, MARLO took 15 successful steps with no boom to stable itself

Arctic fox

The Arctic fox known as the white fox, polar fox, or snow fox, is a small fox native to the Arctic regions of the Northern Hemisphere and common throughout the Arctic tundra biome. It is well adapted to living in cold environments, is best known for its thick, warm fur, used as camouflage. In the wild, most individuals do not live past their first year but some exceptional ones survive up to 11 years, its body length ranges from 46 to 68 cm, with a rounded body shape to minimize the escape of body heat. The Arctic fox preys on many small creatures such as lemmings, ringed seal pups, fish and seabirds, it eats carrion, berries and insects and other small invertebrates. Arctic foxes form monogamous pairs during the breeding season and they stay together to raise their young in complex underground dens. Other family members may assist in raising their young. Natural predators of the Arctic fox are golden eagles, polar bears, red foxes and grizzly bears. Arctic foxes must endure a temperature difference of up to 90–100 °C between the external environment and their internal core temperature.

To prevent heat loss, the Arctic fox curls up tucking its legs and head under its body and behind its furry tail. This position gives the fox the smallest surface area to volume ratio and protects the least insulated areas. Arctic foxes stay warm by getting out of the wind and residing in their dens. Although the Arctic foxes are active year-round and do not hibernate, they attempt to preserve fat by reducing their locomotor activity, they build up their fat reserves in the autumn, sometimes increasing their body weight by more than 50%. This provides greater insulation during a source of energy when food is scarce. In the spring, the Arctic fox's attention switches to reproduction and a home for their potential offspring, they live in large dens in frost-free raised ground. These are complex systems of tunnels covering as much as 1,000 m2 and are in eskers, long ridges of sedimentary material deposited in glaciated regions; these dens are used by many generations of foxes. Arctic foxes tend to select dens that are accessible with many entrances, that are clear from snow and ice making it easier to burrow in.

The Arctic fox builds and chooses dens that face southward towards the sun, which makes the den warmer. Arctic foxes prefer large, maze-like dens for predator evasion and a quick escape when red foxes are in the area. Natal dens are found in rugged terrain, which may provide more protection for the pups. But, the parents will relocate litters to nearby dens to avoid predators; when red foxes are not in the region, Arctic foxes will use dens that the red fox occupied. Shelter quality is more important to the Arctic fox; the main prey in the tundra is lemmings, why the white fox is called the “lemming fox.” The white fox's reproduction rates reflect the lemming population density, which cyclically fluctuates every 3–5 years. When lemmings are abundant, the white fox can give birth to 18 pups, but they do not reproduce when food is scarce; the “coastal fox” or blue fox lives in an environment where food availability is consistent, they will have up to 5 pups every year. Breeding takes place in April and May, the gestation period is about 52 days.

Litters may contain as many as 25. The young are weaned by 9 weeks of age. Arctic foxes are monogamous and both parents will care for the offspring; when predators and prey are abundant, Arctic foxes are more to be promiscuous and display more complex social structures. Larger packs of foxes consisting of breeding or non-breeding males or females can guard a single territory more proficiently to increase pup survival; when resources are scarce, competition increases and the number of foxes in a territory decreases. On the coasts of Svalbard, the frequency of complex social structures is larger than inland foxes that remain monogamous due to food availability. In Scandinavia, there are more complex social structures compared to other populations due to the presence of the red fox. Conservationists are supplying the declining population with supplemental food. One unique case, however, is Iceland; the older offspring remain within their parent's territory though predators are absent and there are fewer resources, which may indicate kin selection in the fox.

Arctic foxes eat any small animal they can find, including lemmings, other rodents, birds, eggs and carrion. They scavenge on carcasses left by larger predators such as wolves and polar bears, in times of scarcity eat their feces. In areas where they are present, lemmings are their most common prey, a family of foxes can eat dozens of lemmings each day. In some locations in northern Canada, a high seasonal abundance of migrating birds that breed in the area may provide an important food source. On the coast of Iceland and other islands, their diet consists predominantly of birds. During April and May, the Arctic fox preys on ringed seal pups when the young animals are confined to a snow den and are helpless, they consume berries and seaweed, so they may be considered omnivores. This fox is a significant bird-egg predator, consuming eggs of all except the largest tundra bird species; when food is overabundant, the Arctic fox buries the surp