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Do you burn more calories exercising in the cold? Here’s what the science says.

As the winter weather gets colder every year, people exercise less than other seasons. At the same time, they usually consume rich foods that will feed the body with a tremendous amount of calories. These pleasant habits in winter can dramatically increase your weight in just a few months. People who are aware of it dream of a way to lose weight more efficiently.
Some of you may have heard that exercising at the cold temperature can burn more calories. You might hear it from your E-mail ads, newspapers or magazines and it is true according to a press release from the University of Albany titled, “Winter Exercise Burns More Calories, Especially for Women.” Everybody knows that it consumes a lot of energy when it is cold. So from now on, we will look at the intuitive facts about it.
First, our body produces heat with burning calories when the temperature is below 0 degrees Celsius. We call it ‘thermogenesis’. Here’s a way of thermogenesis: shivering. Involuntary tremors of the muscles generate warmth and keep our body temperature (37 degrees Celsius). Or your body may generate the heat by burning off ‘brown fat,’ the kind of fat tissue whose main function is heat production. Brown fats produce heat while white fats preserve.Aaron Cypess, a metabolism and brown fat researcher at the National Institutes of Health, explained the difference between them with the following comparison. “They both have fuel or fat, but the oil tanker stores it for use later, and that’s the white fat. The sports car stores fuel to burn it, and that’s the brown fat.” We call this ‘non-shivering thermogenesis.’
“You don’t even know its happening, it’s below the radar of your conscious thought, but it’s there ticking away,” said Herman Pontzer, an associate professor at Hunter College who studies energetics. Going back to this topic again, assuming that you exercise in cold weather, we have an obstacle. When you exercise, your muscles can produce enough heat by moving. Therefore, when you exercise, enough heat is produced that you do not have to consume the extra calories by burning more brown fat. On the other hand, if you sit in thin clothes in cold weather, your body will start shivering its calories to keep its temperature. “The best way to use the cold to burn more calories would be to not exercise while you’re outdoors,” Pontzer added. “You’d get your brown fat cooking and making heat, and might even start shivering, all of which burns calories.”
Cypess imagined a scenario in which when a person wears light clothing at sub-zero temperatures, exercise cannot maintain body temperature and extra thermogenesis begins.But even in this case, Cypess said, you can generate additional calories. The study was conducted with all participants in a cold room all day, and participants burned 150-200 calories more. Again, that’s a full day of cold, not an hour’s worth of outdoor activity.
However, you must remember that physical activity makes up an extremely small part of the total calorie consumption during the day. There are three parts which use calories. First one is your basal metabolic rate. It is the energy used for basic functioning when the body is at rest. And the second one is the energy used to break down food. And then last, our body burns calories for the energy used in physical activity. For most people, the basal metabolic rate accounts for 60 to 80 percent of total energy expenditure. Digesting food accounts for about 10 percent. That leaves only 10 to 30 percent for physical activity, of which exercise is only a subset. Thermogenesis is an even more minor player, Cypess said, usually accounting for less than five or 10 percent of your total energy expenditure (depending on how much time you’ve spent in the cold). Therefore, exercising in cold weather might be not a very efficient idea than we expected.
So, if you want to make up for the overeating of the previous day, it will be more efficient to consider the amount of meal afterward rather than trying to exercise comfortably. Only consistent exercise will be the answer for the winter.




Is Brain Necessary for a Growing Frog?

The embryonic brain of a frog is busy long before it is completely formed. What it usually does is supervising the process of forming the layout of complex patterns of muscles and nerve fibers by sending signals to the part far from it just a day after fertilization. So, if the brain of a frog embryo is missing, the growth of its body goes wrong, reported in Nature Communications on September 25.

The result of this research from brainless embryos and tadpoles helps the biologists to understand the signals of the brain which are involved in the correct development of muscles and nerve fibers. Scientists have usually researched short-range signals that occur between two neighboring cells, not a long one. So, this research is the first example of investigating long-range signals.

Celia Herrera-Rincon of Tufts University in Medford, Mass., and colleagues devised a simple way to observe the body growth of the brainless tadpole. They got rid of growing brains of the African clawed frog embryos just a day after fertilization. Surprisingly, they succeeded in becoming tadpoles from embryos without the brain and became innovative experiment result showing that some organisms can grow without a brain.

This experiment revealed that brains are not essential to the body growth of embryos. However, there are also side effects of having no brain. The brain directs and guides the behavior of the parts of the body before they fully grow. Normally, muscle fibers form a stacked chevron pattern. But in brainless tadpoles, they form incorrectly bungled pattern. “The borders between segments are all wonky,” says the study coauthor Michael Levin, also of Tufts University. “They can’t keep a straight line.”

Nerve fibers spreading on the body of the tadpole were also abnormally grown in the brainless frog embryos. Nerve fibers surrounding the bodies of the tadpoles formed a confusing pattern in the wrong places during their growth. Muscle and nerve abnormalities have been found to be the biggest problems, and major organs such as the heart are also thought to be defective in those embryos, and further research is required to clarify those defects.

In addition, the growth process of brainless embryos was interrupted by certain substances that would not interfere normal embryo’s development. Therefore, it might be reasonable to conclude that the brain of a frog embryo blocks harmful substances at the beginning of its growth.

Scientists were also interested in how the brain transmits long-distance signals to distant cells during the growth process. They do not know the exact process but have some idea about it. Injection of chemical messengers and proteins like acetylcholine and  HCN2 improved the development of muscle system in brainless frog embryos. However, further research is needed to find out if those injections are actually mimicking the process of the embryo’s brain.

Although frogs and mammals cannot be identified as same, it seems plausible that this principle can be applied to humans because the substances forming the bodies are fundamentally same in both organisms.



Tongues ‘taste’ water by sensing sour

All we know about water is that water is an odorless, tasteless, slightly compressible liquid when it’s pure. However, when we drink water, we can know that it’s water. It might be unsurprising to notice that we’re drinking something liquid. But how do we know that it’s water, not syrup? Then, does it mean that water has a taste? – actually not. According to the new study, we can recognize the water not by tasting the water itself, but by sensing acid which is produced when we drink water.

All mammals need water to sustain their life. When we drink water, we have to drink the water through our mouth.According to Yuki Oka who studies the brain at the California Institute of Technology in Pasadena, our tongue has evolved to detect some necessary materials for survival like salt and sugar. This, in other words, means that the sense of detecting water would have evolved.

It is already found that a brain area called the hypothalamus controls thirstiness of mammals. But a brain cannot decide the taste of something alone because, in order to taste something, the brain should cooperate with a mouth and receive a signal from it to know what the person’s eating or drinking. Oka says, “There has to be a sensor that senses water, so we choose the right fluid.” If we cannot distinguish the water from others, we might make a fatal decision, such as drinking poison instead of water.

To prove the water sensor, Oka and his group used mice. They dripped different flavors of liquid onto mice’s tongues. They observed a signal from the nerve cells attached to the taste buds when they were drinking, and mice showed a great nerve response to all tastes. However, the main point is that they reacted to water similarly. Somehow, the scientists discovered that taste buds are able to detect water.

Our mouth is filled with a lot of saliva— a mixture of enzymes and other molecules. Also, the mouth includes bicarbonate ions (HCO3-), which make saliva more basic. The pure water has lower pH than basic saliva. When we pour the water into the mouth, it washes out the basic saliva and enzymes in our mouth instantly starts to replace the ions. It combines carbon dioxide and water to produce bicarbonate. As a side effect, it also produces protons. The bicarbonate is basic, but the protons are acid. Then, the receptors on our tongue detect acid that we usually call ‘sour flavor’ and sends a signal to the brain.

To confirm this, Oka and his group used a technique called optogenetics. In this method, scientists insert light-sensitive molecules, which trigger an electrical impulse when shone with light, inside cells. With this principle, Oka’s team added a light-sensitive molecule to the sour-sensing taste bud cells of mice. As they shone the light to their tongues, they started to lick the light as if they lick the water. By stimulating acid sensor, they misunderstood it as water.

To the other group of mice, Oka’s team removed the sour-sensing molecule by blocking the genetic instructions that make this molecule. As a result, they weren’t able to know whether what they’re drinking is water or not. They even drank thin oil instead. Oka and his group published their results on May 29 in the journal Nature Neuroscience.

Scott Sternson, who studies brain’s mechanism for controlling animal behavior at a Howard Hughes Medical Institute research center in Ashburn, VA, says it’s crucial to learn how we sense simple but vital things, such as water. “It’s important for the basic understanding of how our bodies work,” he says.

Some people might think it’s a weird concept that the water has a sour ‘taste’. Flavor is a complex interaction between taste and smell. So, detecting water is quite different with tasting. Water may still taste like nothing, but to our tongues, it’s definitely something.



Science of cycling remains still largely mysterious


Recently, a bicycle has become not only a transportation but also a trend item. Environmental issues contributed to the growth of bicycle market. As the bicycle market grew, more and more people started to buy and ride their own bicycle. However, there are only a few people who understand the intricacies of how cycling actually works. Let’s take a look at some questions about the bicycle.

What do we know about the bicycle? We know one simple principle: pedal turns a gear that turns a wheel. But it’s physics that is really fascinating. As we think more deeply, more and more mysteries appear — how the bicycle goes straight, what factors work to balance when it moves, etc. Quantum physicist Michael Brooks summed it up nicely in a 2013 article in the New Statesman: “Forget mysterious dark matter and the inexplicable accelerating expansion of the universe; the bicycle represents a far more embarrassing hole in the accomplishments of physics.”

Then, you might think that the design of bicycle has the key of the physics. The answer is, it actually not. Indeed, bicycle manufacturers put a lot of effort and energy in designing bicycles. They put new carbon fiber frames, different sized wheels or tires with different thicknesses. But these are the result guessed by a lot of tests, not mathematically calculated theories.

Although scientists don’t know the exact factor, we know some simple basics. Bike going straightly isn’t just because of the force of momentum pushing it there. First, the bike can’t go straight if the handlebar is fixed. Second, one of the key figures is handlebar angle. The angled handlebar makes an effect of sliding from tilted wall. This is because the steering axis and the contact point are at different places, so the front tire moves towards the steering axis. That helps the bike self-steer and makes the bicycle stable when a rider is on it. What we still don’t know is how these forces, as well as the gyroscopic effect of the tires turning, interact with one another.

The reality is that bike design really hasn’t improved in decades, says Jim Papadopoulos. People have just tried to improve the appearance and reduce the weight of bicycles. So, what we can improve now is change the rider. To bicycles, riders are the most important factor for getting balanced. The aerodynamic position of a rider is certainly important if the road is not really smooth. We can credit the bike for a lot of things, but the real machine that we have to think about more is the rider driving the bicycle forward.



On rough seas, the stability of ships can be a matter of life and death. If a ship loses balance, then it could shrink, which would effect the life of all the people who are on the ship. To prevent these ships from upsetting, a new ship-stabilizing mechanism called ‘Gyroscope’ is now applied to many ships.

It’s actually hard to call this technology a “brand new tech.” because it was already invented in 1850s by a Frenchman Leon Foucault. A gyroscope is a spinning wheel, called the rotor, that rotates around an axis. The rotor is mounted between two gimbals that turns around their own axes. This means that when pressure is exerted on the gimbals, the rotor is unaffected, making it a useful tool to measure compass headings and pitch, roll, or yaw angles—useful for sailors trying to find the horizon on a foggy morning, or in a spacecraft which headed to the ISS.

Other than ship-stabilizing and guiding, gyroscope is used in many important tools like the Hubble Space Telescope, race cars, airplanes, and cell phones. Pokemon Go’s augmented reality also uses gyroscope.

In a boat, the natural rocking of the water moves the spinning gyroscope, producing pressure known as ‘torc.’ As the boat rolls, the gyro tilts fore and aft. This motion comes from the stabilizers which use the energy produced by pushing the spinning gyroscope off its vertical axis to correct the boat’s heel. It’s basically the same principle with a surfer adjusting his body’s position on his board to match a wave’s surface

The problem, though, is that until recently, gyroscopic stabilizers were too heavy and big that it weighted about 100 tons because their power depended on their size and mass. Huge space was needed to take stabilizer, so only huge ships could apply it. However, In 1970s new kind of stabilizer called ‘fin stabilizer’ was invented for the small ships. It looked like fins, and they moved up and down like wing airplane so that it can push the water and stabilize the ship. But fins, though effective, required a lot of power, and changed the direction of the ship a bit.

Researchers are still working on scaling the stabilizer down so that every boats in every sizes can use it. Researchers revealed their next goal that is to make a stabilizer for 20-foot boats. While the early adapters might be luxury ships, the company is seeing an uptick in commercial adoption too.

Widespread usage of stabilizers, Semprevivo hopes, will help improve safety conditions on the sea. “We have an opportunity,” Semprevivo says, “to see what our product can do.”

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Biology’s ‘breadboard’


Our brain, which is called the most complex thing in the universe, have 86 billion neurons with trillions of yet-unmapped connections. Understanding how the brain works is difficult problem which has afflicted the mankind for millennia. But this new study can offer the solution for the psychiatric disorders that made many people to suffer. To understand the brain, a roundworm, C elegans, is good model because it has only 302 neurons, which were completely mapped, with 6,000 connections. It looks like circuit board of biology. Although the brain has simple structure, it forms from simple reactions like searching for food and learning to avoid venom to complex reactions such as social behaviors.

The subject which says understanding this simple system will bring a development of understanding human brain was published on December 26, 2016, in Nature Methods.

Specifically, the idea of breadboards which help adding and correcting circuit elements in electrical and computer engineering is utilized in biology. In order to understand how the neural circuits in brains generate behavior, scientists need to control the activity of neurons as their needs. To do this, researchers have developed robust tools (transgenic actuators), that use drugs or light to activate or silence the neurons in which they are expressed.

Navin Pokala, Ph.D., assistant professor of Life Sciences at New York Institute of Technology (NYIT) College of Arts and Sciences, adapted the GAL4-UAS system for expressing transgenes in the nematode C elegans with researchers at Caltech university. This system, which uses a gene regulatory proteins from yeasts, greatly reduces the time and cost for making new cell-actuator combinations by simply mating already-constructed animals.

Pokala and his collaborators are planning to experiment variations of the GAL4-UAS system to control expression of actuator gene more precisely. Transgenic animal construction allows systematic change of the cells in the nervous system. It allows Pokala and colleagues to build a database linking neural perturbations to behaviors. As it combined with the previously mapped circuit wiring, this database will be a valuable resource for developing and testing models of nervous system function.



Genes Linked to High Blood Pressure risk

These days, many scientists have been working on research to find more effective treatment for high blood pressure.

Especially, a team from the University of Leicester, working with colleges from the Queen Mary University of London and the University of Cambridge, have found ‘31 gene areas’ which seems to related to blood pressure. For this study, more than 347,000 people participated in it. This scale is the largest of this kind of study.

The discoveries include DNA changes in three genes that have much larger effects on blood pressure in the population than previously seen.

Dr. Louise Wain, from Leicester Institute of Precision Medicine, who co-led the genetic analysis in the study, said that this study provides essential information for precision medicine and allows patients to be treated with targeted therapy in earliest time to prevent the hypertension. And he also said that the first-class, high-performance computing facilities at the University of Leicester made this study to be able to set large scale of data.

High blood pressure – hypertension – is a major cause of cardiovascular disease and early death.

For the study, about 200 investigators from 15 countries participated. The teams investigated genotypes and health records to find the relevance between their genetic structure and cardiovascular health. Published in Nature Genetics, the research found variants in three genes that very small ratio of population have but is twice as much as effective to the hypertension.

Professor Patrick Munroe from Queen Mary’s University of London, the study author, said that this research can bring new development in treatment of hypertension and also can help us to understand the genetic knowledges and new biological pathways.

Professor Jeremy Pearson, associate medical director of the British Heart Foundation, which part-funded the research, also said that this study has identified genes that have larger effects on blood pressure than previously found.

The study was also funded by the National Institute for Health Research, the National Institute of Health, Wellcome Trust and Medical Research Council.


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