Tag: 2019年南京最新场子

Something doesn’t smell right

first_imgFor most animals, the scent of rotting meat is powerfully repulsive. But for others, such as carrion-feeding vultures and insects, it’s a scent that can be just as powerfully attractive.The question of why some animals are repelled and others attracted to a particular scent, scientists say, gets at one of the most basic and poorly understood mysteries in neuroscience: How does the brain encode likes and dislikes?Harvard scientists say they’re closer to unraveling that question with the discovery of the first receptors in any species evolved to detect cadaverine and, two of the chemical byproducts responsible for the distinctive — and to most creatures repulsive — smell of rotting flesh. The study is described in a paper published in the Proceedings of the National Academy of Sciences.“This is the first time we’ve identified a receptor for these chemicals,” said Associate Professor of Cell Biology Stephen Liberles, a senior author of the paper. “The larger question we’re interested in is: What does it mean that something is an aversive or attractive odor? How are likes and dislikes encoded in the brain? Understanding the receptors that respond to those cues could give us a powerful inroad to understanding that.”Graduate School of Arts and Sciences student Zecai Liang with Liberles in his lab. Liberles is trying to unravel the scent question: How are likes and dislikes encoded in the brain?Though researchers have long understood that olfaction involves receptors, which detect odors and in turn activate brain neurons, Liberles, together with Nobel laureate Linda Buck, recently discovered a second family of receptors, dubbed trace amine-associated receptors, or TAARs.Though fewer in number than other odorant receptors — mice, for example, have 15, versus more than 1,000 odorant receptors, while humans have 350 receptors and just six TAARs — Liberles said the functions of the TAARs remained largely unknown.“We knew they were olfactory receptors, but we didn’t know what ligands might activate them,” Liberles said of the TAARs. “We know in the taste system there are different families of receptors for bitter and sweet, so we thought the TAARs might be doing something specific in olfaction.”To understand how the TAARs function, researchers sought to identify scents that would activate them, hoping they might offer clues into why a second olfactory system evolved. In recent years, scientists working in Liberles’ lab identified odors that activated six TAARs in mice and seven in rats, nearly all of which were highly aversive.To check TAARs in fish, Liberles’ team worked with colleagues in Germany to implant olfactory receptors in cell cultures and test them against hundreds of possible odorants, hoping to identify which ones activated the receptor.What the researchers discovered, Liberles said, was that one particular receptor appeared to act as a sensor for diamines — a class of chemicals that include cadaverine and putrescine — nearly all of which are notoriously foul-smelling. Later tests using live zebrafish showed that when researchers marked part of a fish tank with the scent of rotting fish, the fish were highly likely to avoid the area.“What’s also interesting is that this odor — like the predator odor we identified in mice — was aversive the very first time the animal encountered it,” Liberles said. “That suggests the aversion is innate — it’s not learned — and that it involves genetic circuits that are genetically predetermined, that exist, dormant, in the animal waiting for it to encounter the odor.“You might like the smell of baking cookies, but it’s only because you’ve learned to associate it with their taste, or the sugar rush you get from eating them,” he continued. “But this aversion is there from birth. That suggests there is some developmental mechanism underlying these circuits. The question is, what is that?”Though researchers have thus far only shown that the TAARs are activated by amines, Liberles said it’s unlikely that is their only role in olfaction.“We’ve been hunting for a unified theme for what the TAARs might be doing,” he said. “One model is that they’re amine receptors, and another is that they’re all encoding for aversion. I don’t think either is quite correct. I think they may have started as amine receptors, but they have since evolved to do other things.”Understanding how odorants like cadaverine and putrescine work in the olfactory system could also shed light on why some scents — such as rotting meat — repel some creatures, but attract others.“Species-specific behavioral responses suggest that somehow the neural circuits are changing from species to species,” Liberles said. “For instance, tests in our lab have shown that trimethylamine is attractive to mice, but highly aversive to rats. Something similar might be happening with cadaverine.“How does that happen? It’s not known,” he continued. “We don’t understand, as a field, how aversive and attractive odors are differentially processed … but identifying the receptor gives us a handle on the neural circuits that are involved. Now that we have the receptor, we can ask basic questions about aversion and attraction circuitry in general. From there, we can begin to understand how attractive and aversive stimuli are differentially encoded, and cadaverine is about as aversive as you can get.” <a href=”https://www.youtube.com/watch?v=oaC2P7IU8dU” rel=”nofollow” target=”_blank”> <img src=”https://img.youtube.com/vi/oaC2P7IU8dU/0.jpg” alt=”0″ title=”How To Choose The Correct Channel Type For Your Video Content ” /> </a>last_img read more

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Colombian Navy launches first domestically manufactured vessel

first_img Other Navy ships built in Colombia “What we have today with this ship, which is 100 percent designed, manufactured and built in Colombia, is the dream of many people who put their hearts, hands, minds and efforts to transform steel into monuments for the homeland, peace, development and security,” said Pinzon. Thanks to the construction of these and other vessels, the Colombian naval industry is respected throughout the world by countries which purchase vessels manufactured in the country. The main mission of the Punta Espada will be to carry out maritime interdiction, patrol and surveillance operations in Colombian waters. Security forces will use it to detect, intercept, and inspect suspicious vessels. . “At the tactical and operational level, Colombia has responded to a number of needs that conflict and drug trafficking have been creating,” said Néstor Alfonso Rosania, a security analyst at the Center for Studies in Security, Defense and International Affairs of Colombia. The Armed Forces of Colombia will continue to receive the best available equipment and technological tools “because they are the ones who have put Colombia on a path towards peace,” the defense minister said. Defense Minister Juan Carlos Pinzón, and the commander of the National Navy, Admiral Hernando Wills, presided over the launching ceremony of the Punta Espada in Cartagena. “Colombia has entered a select group of countries that have the technology and knowledge to build these kind of vessels,” said Rear Adm. Roberto Sáchica, the president of Cotecmar. The ARC Punta Espada – the first CPV produced entirely in Colombia – touched water for the first time October 31. It was produced by the Science and Technology Corporation of Naval, Maritime and Riverine Industry Development (Cotecmar) in conjunction with the Social and Enterprise Defense Group (GSED), which is part of the Defense Ministry. By Dialogo November 28, 2014 “The coastal patrol boat responds to needs from armed conflict and transnational drug trafficking It will provide the Navy with more mobility and achievements in operations against threats facing the country. This boat is not only fundamental to Colombia’s Navy, but it is also important to the Colombian military industry at the international level.” “It is a great start that this patrol boat is already sailing,” Rosania said. “This boat is the result of scientific and technological development that the Colombian government has been implementing in recent years. The Navy understands the need to build vessels to monitor both oceans and prevent drug trafficking from continuing in these areas. Authorities are concentrating their efforts on developing new technologies to combat threats of transnational crime and various related offenses.” “What we have today with this ship, which is 100 percent designed, manufactured and built in Colombia, is the dream of many people who put their hearts, hands, minds and efforts to transform steel into monuments for the homeland, peace, development and security,” said Pinzon. The Colombian military industry has built other Navy vessels. For example, in February the Colombian Navy launched the ARC 20 de Julio, the largest ship built in the country. It was designed and built by Cotecmar. For example, in September 2012, Brazil bought four LPR-40 patrol boats which were manufactured in Cartagena. It is important and interesting that countries like Peru and Colombia are becoming more technical with respect to the Navy. I read about ESMERALDA, a Chilean sailing vessel in AGORA, which until now was the largest, but according to what I read now it will be the UNION. Congratulations to both governments for their interest in becoming one of the big players in this area. Your information is very timely. I work in the National Port Security Commission in Honduras as head of Port Security Audits (APIP in Spanish)… I hope you continue to contribute with more information. “I congratulate everyone who has contributed to these projects, which were no simple feat,” Pinzon said. “These are projects that carry the vision of great people of this country, officers, non-commissioned officers, engineers, sailors and good Colombians, who have visualized Colombia’s real and strategic capacity in naval and maritime matters for several years.” “It is a great start that this patrol boat is already sailing,” Rosania said. “This boat is the result of scientific and technological development that the Colombian government has been implementing in recent years. The Navy understands the need to build vessels to monitor both oceans and prevent drug trafficking from continuing in these areas. Authorities are concentrating their efforts on developing new technologies to combat threats of transnational crime and various related offenses.” The main mission of the Punta Espada will be to carry out maritime interdiction, patrol and surveillance operations in Colombian waters. Security forces will use it to detect, intercept, and inspect suspicious vessels. . The ARC Punta Espada – the first CPV produced entirely in Colombia – touched water for the first time October 31. It was produced by the Science and Technology Corporation of Naval, Maritime and Riverine Industry Development (Cotecmar) in conjunction with the Social and Enterprise Defense Group (GSED), which is part of the Defense Ministry. Other Navy ships built in Colombia Thanks to the construction of these and other vessels, the Colombian naval industry is respected throughout the world by countries which purchase vessels manufactured in the country. “At the tactical and operational level, Colombia has responded to a number of needs that conflict and drug trafficking have been creating,” said Néstor Alfonso Rosania, a security analyst at the Center for Studies in Security, Defense and International Affairs of Colombia. “The coastal patrol boat responds to needs from armed conflict and transnational drug trafficking It will provide the Navy with more mobility and achievements in operations against threats facing the country. This boat is not only fundamental to Colombia’s Navy, but it is also important to the Colombian military industry at the international level.” Improving Colombia’s strategic capacity The Punta Espada will help the Armed Forces continue on that path. Military officials appointed Naval Lt. Cmdr. Henry Mauricio Barón Franco as the patrol boat’s commander. He will take command of a vessel that measures 45.25 meters in length, 7.1 meters in beam and 1.84 meters in draught. It can accommodate a crew of 23 people, and is powered by two diesel engines which drive a fixed pitched propeller. It’s also outfitted with a 25-mm caliber cannon and two 60-mm caliber machine guns. Colombia’s security forces recently obtained an important tool in their fight against international drug trafficking – a coastal patrol vessel (CPV). Improving Colombia’s strategic capacity Colombian manufacturers used global technology to build the patrol boat, which has the capability of refueling rapid response boats. The Punta Espada will help the Armed Forces continue on that path. Military officials appointed Naval Lt. Cmdr. Henry Mauricio Barón Franco as the patrol boat’s commander. He will take command of a vessel that measures 45.25 meters in length, 7.1 meters in beam and 1.84 meters in draught. It can accommodate a crew of 23 people, and is powered by two diesel engines which drive a fixed pitched propeller. It’s also outfitted with a 25-mm caliber cannon and two 60-mm caliber machine guns. “Colombia has entered a select group of countries that have the technology and knowledge to build these kind of vessels,” said Rear Adm. Roberto Sáchica, the president of Cotecmar. The Armed Forces of Colombia will continue to receive the best available equipment and technological tools “because they are the ones who have put Colombia on a path towards peace,” the defense minister said. Defense Minister Juan Carlos Pinzón, and the commander of the National Navy, Admiral Hernando Wills, presided over the launching ceremony of the Punta Espada in Cartagena. The Colombian military industry has built other Navy vessels. For example, in February the Colombian Navy launched the ARC 20 de Julio, the largest ship built in the country. It was designed and built by Cotecmar. Colombia’s security forces recently obtained an important tool in their fight against international drug trafficking – a coastal patrol vessel (CPV). “I congratulate everyone who has contributed to these projects, which were no simple feat,” Pinzon said. “These are projects that carry the vision of great people of this country, officers, non-commissioned officers, engineers, sailors and good Colombians, who have visualized Colombia’s real and strategic capacity in naval and maritime matters for several years.” For example, in September 2012, Brazil bought four LPR-40 patrol boats which were manufactured in Cartagena. Colombian manufacturers used global technology to build the patrol boat, which has the capability of refueling rapid response boats. last_img read more

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From February to September, 47% less traffic was recorded

first_imgtax administration However, a certain recovery was achieved in September, so the decline is much smaller. Comparing the second week of September 2020 (07.09.-13.09.2020), with the third week of September 2020 (14.09.-20.09.2020), the data show that for all activities it is visible 2% account reduction, while the invoice amount is lower by 3%. In activity I – providing accommodation and food preparation and serving is visible reduction of the number of accounts by 4%, and reduction of the amount of invoices by 8%. For all activities in the period from 24.02. to 20.09.2020. in relation to the period from 23.02.- 20.09.2019. it’s visible 26% reduction in the number of accounts, i 18% invoice reduction, say data from the Tax Administration. But the data also reveals a big drop in the tourism sector. Namely, in activity I – providing accommodation and food preparation and serving is visible 40% reduction in the number of invoices and 47% in the amount of the invoice. Turned into numbers, it is about ten billion kuna less turnover.center_img For all activities in the period from 14.09. to 20.09.2020. year compared to the same period in 2019 is visible 19% reduction in the number of accounts, i 18% invoice amount reduction.  In activity I – providing accommodation and food preparation and serving is visible 27% account reduction, and invoice amount of 48%. Also, comparing the period of 14.09. to 20.09.2020. in relation to the same period in 2019, the following is visible:last_img read more

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