O fotógrafo Greg Lecoeur viajou de sua cidade natal, em Nice (França) até Cape Point na África do Sul para documentar a migração de animais.
Ele registrou com sua câmera, fotografias incríveis enquanto navegava em águas profundas de golfinhos , focas, baleias e aves, que atacavam um banco de sardinhas.
http://www.fotoshot.com.br/11-imagens-espetaculares-de-animais-dentro-do-mar/
 The computational algorithm allowed for calculation of micronutrient content in different foods, and hereby it is possible to calculate how diet impacts the metabolism in the human gut microbiome. In the study it was found that subjects with low gene counts (LGC), having a compressed gut microbiota, respond better to dietary intervention than subjects with a high gene count (HGC), due to differences in the metabolism of the gut microbiota in the two groups. Credit: Image courtesy of Chalmers University of Technology New research enables "tailored" diet advice -- based on our personal gut microbiome -- for persons who want to lose weight and reduce the risk of disease. Systems biologists at Chalmers University of Technology have for the first time successfully identified in detail how some of our most common intestinal bacteria interact during metabolism. The researchers at Chalmers University of Technology have developed a mathematical calculation platform that makes it possible to predict how different patients will respond to a modified diet, depending on how their gut microbiome is composed. Work has been conducted in cooperation in the context of the EU funded projectMetacardis, coordinated by professor Karine Clement at Institute of Cardiometabolism and Nutrition (Ican, Pitié-Salpêtrière Hospital, Inserm/Sorbonne University) in Paris and also includes professor Fredrik Bäckhed at the University of Gothenburg. "This method allows us to begin identifying each individual bacteria type's metabolism and thus get a handle on the basic mechanisms in human metabolism," says Jens Nielsen, professor of systems biology at Chalmers and head of the research team. There can be up to 1,000 different types of bacteria and other microorganisms in the human digestive system, many of which take part in metabolism in one way or another. The composition of the human gut microbiome greatly varies between individuals, for reasons that are largely unknown. However, research over the past few years has shown that there is a connection between some diseases and the composition of the gut microbiome. "This is clear as regards type 2 diabetes, hardening of the arteries and obesity, for example. There are also indications that the same might apply to depression and the body's ability to respond to various cancer treatments," says Jens Nielsen. Exactly how microorganisms interact with food, the individual and not least each other is extremely complex. Until now it has been very difficult to gain understanding of what the causal links are. In a study that was recently published in Cell Metabolism, however, researchers prove, through clinical trials, that the mathematical modelling they developed works. The point of departure is a diet experiment that was performed at Ican. First the gut microbiome was characterised for individuals in a group of overweight patients, and then they were put on a weight loss diet. Everyone lost weight, which was expected. In patients with low-diversity gut microbiome, however, the content of several substances that generally indicate health risks was also reduced in the individuals' blood and faeces. This was a deviation from the patients who had gut microbiome with greater "biological diversity." Their health situation was not affected to the same extent. Of real interest, however, is that the systems biologists from Chalmers with their modelling tools have largely been able to explain why both patient groups reacted as they did to the diet. "Amongst other things, we have been able to demonstrate that the intestines of the individuals with low-diversity gut microbiome produce fewer amino acids when they follow this diet. This is one explanation for the improved blood chemistry. In the short term, Jens Nielsen believes the research will make it easier for physicians to identify overweight patients who are at higher risk of cardiometabolic disease and could truly achieve major health benefits by modifying their diet and losing weight. Fairly soon it should be possible to design diet recommendations that take the gut microbiome of individual patients into account. Karine Clement is already thinking along these lines and new follow up clinical experiments are being designed. "In the long term we might be able to add intestinal bacteria for patients whose metabolism does not function properly," she explains. What are known as probiotics are already being used -- various yoghurt cultures are one example -- but the task of these bacteria is primarily to stabilise the intestines and create a favourable environment. "The next generation of probiotics will pertain more to adding bacteria that integrate directly with the existing gut microbiome and make a lasting change to the composition," says Jens Nielsen. The company Metabogen was founded based on collaboration between researchers at Chalmers and the University of Gothenburg and it will aim to develop these types of drugs. Story Source: The above post is reprinted from materials provided by Chalmers University of Technology. Note: Materials may be edited for content and length. Journal Reference:
http://www.sciencedaily.com/releases/2015/09/150910091400.htm
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NASA's Dawn Spacecraft took this image of Gaue crater, the large crater on the bottom, on Ceres. Gaue is a Germanic goddess to whom offerings are made in harvesting rye.
The center of this crater is sunken in. Its diameter is 84 kilometers (52 miles). The resolution of the image is 450 feet (140 meters) per pixel.
The image was taken from a distance of 915 miles (1,470 kilometers) on August 18, 2015.
Dawn's mission is managed by NASA's Jet Propulsion Laboratory for NASA's Science Mission Directorate in Washington. Dawn is a project of the directorate's Discovery Program, managed by NASA's Marshall Space Flight Center in Huntsville, Alabama. UCLA is responsible for overall Dawn mission science. Orbital ATK, Inc., in Dulles, Virginia, designed and built the spacecraft. The German Aerospace Center, the Max Planck Institute for Solar System Research, the Italian Space Agency and the Italian National Astrophysical Institute are international partners on the mission team. For a complete list of acknowledgments, see http://dawn.jpl.nasa.gov/mission.
For more information about the Dawn mission, visit http://dawn.jpl.nasa.gov.
Image Credit:
NASA/JPL-Caltech/UCLA/MPS/DLR/IDA
Last Updated: Aug. 25, 2015
Editor: Tony Greicius
 Earth's fault lines between tectonic plates (stock image). The cores of continents have long been considered geologically extremely stable. However, a team of scientists has now discovered that these cratons that were assumed to be "as solid as a rock" are not that solid after all. Credit: © Mopic / Fotolia In the course of billions of years continents break up, drift apart, and are pushed back together again. The cores of continents are, however, geologically extremely stable and have survived up to 3.8 billions of years. These cores that are called cratons are the oldest known geological features of our planet. It was assumed that the cratons are stable because of their especially solid structure due to relatively low temperatures compared to the surrounding mantle. A team of German-American scientists now discovered that these cratons that were assumed to be "as solid as a rock" are not that solid after all. The team leading by Dr. Mikhail Kaban from the GFZ German Research Centre for Geosciences now discovered that the craton below the North American continent is extremely deformed: its root is shifted relative to the center of the craton by 850 kilometers towards the west-southwest. This fact is in contrast to the prevailing assumptions that these continental roots did not undergo substantial changes after their formation 2.5 to 3.8 billion years ago. The study that appears in the latest online publication of Nature Geoscience contradicts this traditional view. "We combined and analyzed several data sets from Earth's gravity field, topography, seismology, and crustal structure and constructed a three dimensional density model of the composition of the lithosphere below North America," explains GFZ scientist Mikhail Kaban. "It became apparent that the lower part of the cratonic root was shifted by about 850 kilometers." What caused the deformation of the stable and solid craton? A model of the flows in Earth's mantle below North America, developed by the scientists, reveals that the mantle material below 200 kilometers flows westward at a velocity of about 4 millimeters per year. This is in concordance with the movement of the tectonic plate. Due to the basal drag of this flow the lower part of the cratonic lithosphere is shifted. "This indicates that the craton is not as solid and as insensitive to the mantle flow as was previously assumed," Kaban completes. There is far more mechanical, chemical, and thermal interaction between the craton of billions of years in age and its surrounding in the upper mantle of Earth than previously thought.
Story Source: The above post is reprinted from materials provided by Helmholtz Centre Potsdam - GFZ German Research Centre for Geosciences. Note: Materials may be edited for content and length. Journal Reference:
http://www.sciencedaily.com/releases/2015/09/150907113917.htm
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For years we have believed that ordered polymer chains increase the conductivity of plastic. And a new generation of polymers has been developed. It is true that these new polymers are more conductive, but for completely different reasons -- according to researchers from Linköping University and Stanford University.Organic electronics has many advantages: it is inexpensive, flexible and lightweight it does not consume any scarce resources. In terms of applications, we are only limited by our imaginations. There has been a lot of development in polymers since the phenomenon of conducting and semi-conducting plastics was discovered and in 2000 awarded a Nobel Prize. Their weakness is still speed; plastics conduct a charge slowly, compared to silicon, for instance. A polymer consists of long chains of hydrocarbon, where other elements are bound, which give the particular plastic its properties. Research is underway, and researchers and developers in the chemical industry have developed new polymers that conduct better. "The charge is transported two to three times faster in the latest generation polymers," explains Dr Simone Fabiano, researcher at the Laboratory of Organic Electronics, Linköping University, Campus Norrköping. He is the lead author of the article being published in the Proceedings of the National Academy of Sciences, PNAS. Until now people have tried to get the polymer chains to lie as well ordered as possible. The idea is that it should be easy for the charge to jump between the chains if they are organised in rows. Dr Fabiano compares the polymer chains to spaghetti, that you try to line up next to each other, instead of all tangled up, like when it has been tipped from a pot. But to their surprise, the researchers observed during their experiments that the charge seems to travel as quickly in an unordered polymer as in an ordered, crystalline one. Together with colleagues at the Laboratory of Organic Electronics in Norrköping and in Stanford, California, Dr Fabiano has discovered why this occurs. They have shown that crystallinity, the degree of structural order in a solid, actually does not play a part in how quickly a polymer conducts. "We see that the new generation of polymers has such small defects that the charge moves faster along the chain instead of jumping between the chains. For the charge carrier, it takes less energy to travel along the chain than to jump to the adjacent one. So the polymer is a faster conductor," explains Simone Fabiano. Instead, the ideal situation seems to be that the polymer has some a degree of disorder and that the polymer chains aggregate from time to time, that is, they cross each other, to make the transition easier. To further increase conductivity in the conducting and semiconducting polymers, and to develop faster electronic components, Dr Fabiano now places his hope on the chemists. "It is about design at the molecular level. That they can continue to reduce the defects and focus on enabling the polymer chains to make better contact with each other, rather than forming large crystalslying in order." Story Source: The above post is reprinted from materials provided by Linköping Universitet.Note: Materials may be edited for content and length. Journal Reference:
http://www.sciencedaily.com/releases/2015/09/150909090827.htm
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| Exercise is an important part of any diabetes treatment plan. To avoid potential problems, check your blood sugar before, during and after exercise. Diabetes and exercise go hand in hand, at least when it comes to managing your diabetes. Exercise can help you improve your blood sugar control, as well as boost your overall fitness and reduce your risk of heart disease and stroke. But diabetes and exercise pose unique challenges, too. Remember to track your blood sugar before, during and after exercise. Your records will reveal how your body responds to exercise — and help you prevent potentially dangerous blood sugar fluctuations. Before exercise: Check your blood sugar before your workoutBefore jumping into a fitness program, get your doctor's OK to exercise — especially if you've been inactive. Discuss with your doctor which activities you're contemplating and the best time to exercise, as well as the potential impact of medications on your blood sugar as you become more active. For the best health benefits, experts recommend 150 minutes a week of moderately intense physical activities such as:
If you're taking insulin or medications that can cause low blood sugar (hypoglycemia), test your blood sugar 30 minutes before exercising and approximately every 30 minutes during exercise. This will help you determine if your blood sugar level is stable, rising or falling and if it's safe to keep exercising.
Consider these general guidelines relative to your blood sugar level — measured in milligrams per deciliter (mg/dL) or millimoles per liter (mmol/L).
See more In-depthDuring exercise: Watch for symptoms of low blood sugar During exercise, low blood sugar is sometimes a concern. If you're planning a long workout, check your blood sugar every 30 minutes — especially if you're trying a new activity or increasing the intensity or duration of your workout. This may be difficult if you're participating in outdoor activities or sports. However, this precaution is necessary until you know how your blood sugar responds to changes in your exercise habits. Stop exercising if:
Eat or drink something to raise your blood sugar level, such as:
Recheck your blood sugar 15 minutes later. If it's still too low, have another serving and test again 15 minutes later. Repeat as needed until your blood sugar reaches at least 70 mg/dL (3.9 mmol/L). If you haven't finished your workout, continue once your blood sugar returns to a safe range. After exercise: Check your blood sugar againCheck your blood sugar right away after exercise and again several times during the next few hours. Exercise draws on reserve sugar stored in your muscles and liver. As your body rebuilds these stores, it takes sugar from your blood. The more strenuous your workout, the longer your blood sugar will be affected. Low blood sugar is possible even several hours after exercise. If you do have low blood sugar after exercise, eat a small carbohydrate-containing snack, such as fruit or crackers, or drink a small glass of fruit juice. Exercise can be beneficial to your health in many ways, but if you have diabetes, testing your blood sugar before, during and after exercise may be just as important as the exercise itself. Feb. 22, 2014 References
http://www.mayoclinic.org/diseases-conditions/diabetes/in-depth/diabetes-and-exercise/art-20045697
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Zinc, in commerce also spelter, is a chemical element with symbol Znand atomic number 30. It is the first element of group 12 of theperiodic table. In some respects zinc is chemically similar tomagnesium: its ion is of similar size and its only common oxidation state is +2. Zinc is the 24th most abundant element in Earth's crust and has five stable isotopes. The most common zinc ore is sphalerite(zinc blende), a zinc sulfide mineral. The largest mineable amounts are found in Australia, Asia, and the United States. Zinc production includes froth flotation of the ore, roasting, and final extraction usingelectricity (electrowinning). Brass, which is an alloy of copper and zinc, has been used since at least the 10th century BC in Judea and by the 7th century BC in Ancient Greece. Zinc metal was not produced on a large scale until the 12th century in India and was unknown to Europe until the end of the 16th century. The mines of Rajasthan have given definite evidence of zinc production going back to the 6th century BC. To date, the oldest evidence of pure zinc comes from Zawar, in Rajasthan, as early as the 9th century AD when a distillation process was employed to make pure zinc. Alchemists burned zinc in air to form what they called "philosopher's wool" or "white snow". The element was probably named by the alchemist Paracelsus after the German word Zinke. German chemist Andreas Sigismund Marggraf is credited with discovering pure metallic zinc in 1746. Work by Luigi Galvani and Alessandro Volta uncovered the electrochemical properties of zinc by 1800. Corrosion-resistant zinc plating of iron (hot-dip galvanizing) is the major application for zinc. Other applications are in batteries, small non-structural castings, and alloys, such as brass. A variety of zinc compounds are commonly used, such as zinc carbonate and zinc gluconate (as dietary supplements), zinc chloride (in deodorants), zinc pyrithione (anti-dandruff shampoos), zinc sulfide (in luminescent paints), and zinc methyl or zinc diethyl in the organic laboratory. Zinc is an essential mineral perceived by the public today as being of "exceptional biologic and public health importance", especially regarding prenatal and postnatal development. Zinc deficiency affects about two billion people in the developing world and is associated with many diseases. In children it causes growth retardation, delayed sexual maturation, infection susceptibility, and diarrhea. Enzymes with a zinc atom in the reactive center are widespread in biochemistry, such as alcohol dehydrogenase in humans. Consumption of excess zinc can causeataxia, lethargy and copper deficiency.
Zinc is an essential trace element for humans and other animals, for plants and for microorganisms. Zinc is found in nearly 100 specificenzymes (other sources say 300), serves as structural ions in transcription factors and is stored and transferred in metallothioneins. It is "typically the second most abundant transition metal in organisms" after iron and it is the only metal which appears in all enzyme classes. In proteins, Zn ions are often coordinated to the amino acid side chains of aspartic acid, glutamic acid, cysteine and histidine. The theoretical and computational description of this zinc binding in proteins (as well as that of other transition metals) is difficult. There are 2-4 grams of zinc distributed throughout the human body. Most zinc is in the brain, muscle, bones, kidney, and liver, with the highest concentrations in the prostate and parts of the eye. Semen is particularly rich in zinc, which is a key factor in prostate gland function and reproductive organgrowth. In humans, zinc plays "ubiquitous biological roles". It interacts with "a wide range of organic ligands",and has roles in the metabolism of RNA and DNA,signal transduction, and gene expression. It also regulates apoptosis. A 2006 study estimated that about 10% of human proteins (2800) potentially bind zinc, in addition to hundreds which transport and traffic zinc; a similar in silico study in the plant Arabidopsis thaliana found 2367 zinc-related proteins. In the brain, zinc is stored in specific synaptic vesicles by glutamatergicneurons and can "modulate brain excitability". It plays a key role in synaptic plasticity and so in learning. However, it has been called "the brain's dark horse because it also can be a neurotoxin, suggesting zinc homeostasis plays a critical role in normal functioning of the brain and central nervous system. Enzymes
Zinc fingers help read DNA sequences. Zinc is an efficient Lewis acid, making it a useful catalytic agent in hydroxylationand other enzymatic reactions. The metal also has a flexible coordination geometry, which allows proteins using it to rapidly shift conformations to perform biological reactions. Two examples of zinc-containing enzymes arecarbonic anhydrase and carboxypeptidase, which are vital to the processes ofcarbon dioxide () regulation and digestion of proteins, respectively. In vertebrate blood, carbonic anhydrase converts into bicarbonate and the same enzyme transforms the bicarbonate back into for exhalation through the lungs. Without this enzyme, this conversion would occur about one million times slower at the normal blood pH of 7 or would require a pH of 10 or more. The non-related β-carbonic anhydrase is required in plants for leaf formation, the synthesis of indole acetic acid (auxin) and alcoholic fermentation. Carboxypeptidase cleaves peptide linkages during digestion of proteins. Acoordinate covalent bond is formed between the terminal peptide and a C=O group attached to zinc, which gives the carbon a positive charge. This helps to create a hydrophobic pocket on the enzyme near the zinc, which attracts the non-polar part of the protein being digested Other proteinsZinc serves a purely structural role in zinc fingers, twists and clusters. Zinc fingers form parts of some transcription factors, which are proteins that recognize DNA base sequences during the replication and transcription of DNA. Each of the nine or ten ions in a zinc finger helps maintain the finger's structure by coordinately binding to four amino acids in the transcription factor. The transcription factor wraps around the DNA helix and uses its fingers to accurately bind to the DNA sequence. In blood plasma, zinc is bound to and transported by albumin (60%, low-affinity) and transferrin (10%). Because transferrin also transports iron, excessive iron reduces zinc absorption, and vice versa. A similar antagonism exists with copper. The concentration of zinc in blood plasma stays relatively constant regardless of zinc intake. Cells in the salivary gland, prostate, immune system and intestine use zinc signaling as one way to communicate with other cells. Zinc may be held in metallothionein reserves within microorganisms or in the intestines or liver of animals. Metallothionein in intestinal cells is capable of adjusting absorption of zinc by 15–40%. However, inadequate or excessive zinc intake can be harmful; excess zinc particularly impairs copper absorption because metallothionein absorbs both metals. Dietary intake
Foods & spices containing zinc In the U.S., the Recommended Dietary Allowance (RDA) is 8 mg/day for women and 11 mg/day for men. Median intake in the U.S. around 2000 was 9 mg/day for women and 14 mg/day in men. Oysters, lobster and red meats, especially beef, lamb and liver have some of the highest concentrations of zinc in food. Zinc supplements should only be ingested when there is zinc deficiency or increased zinc necessity (e.g. after surgeries, traumata or burns) Persistent intake of high doses of zinc can cause copper deficiency. The concentration of zinc in plants varies based on levels of the element in soil. When there is adequate zinc in the soil, the food plants that contain the most zinc are wheat (germ and bran) and various seeds (sesame, poppy, alfalfa, celery,mustard). Zinc is also found in beans, nuts, almonds, whole grains, pumpkin seeds, sunflower seeds and blackcurrant. Other sources include fortified food and dietary supplements, which come in various forms. A 1998 review concluded that zinc oxide, one of the most common supplements, and zinc carbonate are nearly insoluble and poorly absorbed in the body. This review cited studies which found low plasma zinc concentrations after zinc oxide and zinc carbonate were consumed compared with those seen after consumption of zinc acetate and sulfate salts. However, harmful excessive supplementation is a problem among the relatively affluent, and should probably not exceed 20 mg/day in healthy people, although the U.S. National Research Council set a Tolerable Upper Intake of 40 mg/day. For fortification, however, a 2003 review recommended zinc oxide in cereals as cheap, stable, and as easily absorbed as more expensive forms. A 2005 study found that various compounds of zinc, including oxide and sulfate, did not show statistically significant differences in absorption when added as fortificants to maize tortillas. A 1987 study found that zinc picolinate was better absorbed than zinc gluconate or zinc citrate. However, a study published in 2008 determined that zinc glycinate is the best absorbed of the four dietary supplement types available. DeficiencyMain article: Zinc deficiency Zinc deficiency is usually due to insufficient dietary intake, but can be associated with malabsorption, acrodermatitis enteropathica, chronic liver disease, chronic renal disease, sickle cell disease, diabetes, malignancy, and other chronic illnesses. Groups at risk for zinc deficiency include the elderly, children in developing countries, and those with renal insufficiency. Symptoms of mild zinc deficiency are diverse. Clinical outcomes include depressed growth, diarrhea, impotence and delayed sexual maturation, alopecia, eye and skin lesions, impaired appetite, altered cognition, impaired host defense properties, defects in carbohydrate utilization, and reproductive teratogenesis. Mild zinc deficiency depresses immunity, although excessive zinc does also. Animals with a diet deficient in zinc require twice as much food in order to attain the same weight gain as animals given sufficient zinc. Despite some concerns, western vegetarians and vegans have not been found to suffer from overt zinc deficiencies any more than meat-eaters.200 Major plant sources of zinc include cooked dried beans, sea vegetables, fortified cereals, soyfoods, nuts, peas, and seeds However, phytates in many whole-grains and fiber in many foods may interfere with zinc absorption and marginal zinc intake has poorly understood effects. The zinc chelator phytate, found in seeds and cereal bran, can contribute to zinc malabsorption.7 There is some evidence to suggest that more than the US RDA (15 mg) of zinc daily may be needed in those whose diet is high in phytates, such as some vegetarians. These considerations must be balanced against the fact that there is a paucity of adequate zinc biomarkers, and the most widely used indicator, plasma zinc, has poor sensitivity and specificity. Diagnosing zinc deficiency is a persistent challenge. Nearly two billion people in the developing world are deficient in zinc. In children it causes an increase in infection and diarrhea, contributing to the death of about 800,000 children worldwide per year. The World Health Organization advocates zinc supplementation for severe malnutrition and diarrhea. Zinc supplements help prevent disease and reduce mortality, especially among children with low birth weight or stunted growth. However, zinc supplements should not be administered alone, because many in the developing world have several deficiencies, and zinc interacts with other micronutrients.
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