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(Phys.org)—A team of researchers with members from several institutions in Germany has found that the female burying beetle gives off a pheromone during parental care that causes male beetles to temper their sexual advances. In their paper published in the journal Nature Communications, the team describes their study of hundreds of the beetles captured in a German forest and brought to their lab. Burying beetles lay their eggs in dead animal carcasses—when the young hatch, the mother, and to some extent, the father take bites from the carcass, chew it, and then feed it to the young. They also both fend off predators. Prior research had shown that during this time period the female emits a gas of some sort, and that there was less sexual activity than normal. In this new effort, the researchers sought to learn the properties of the gas and to determine if it was responsible for the decrease in sexual activity, which in turn led to better care for the young. To find out, the team captured approximately 400 of the beetles, split them into groups of those with offspring, and those without, and then ran several experiments and tests on them. One of the tests involved measuring hormone levels in the females—in so doing, the researchers found that one called 'juvenile hormone III' increased, causing the female to be less fertile during the time she was caring for her young. They also found that she emitted a similar chemical called methyl generate, a pheromone, during the same time frame. Next the team ran several experiments to determine if it was the pheromone that caused the antiaphrodisiac-type effect in males—one of which involved monitoring the release levels of the pheromone and the sexual activity of males when the young were removed from both parents, preventing parental care. They found that the production and emission of the hormone did indeed suppress sexual advances by males, which allowed both to better parent their offspring. The researchers note that the emitted chemical allows both parents to invest more resources into offspring and it represents an effective form of communication between parents that benefits them both and their offspring. Explore further: Older males make better fathers: Mature male beetles work harder, care less about female infidelity More information: Katharina C. Engel et al. A hormone-related female anti-aphrodisiac signals temporary infertility and causes sexual abstinence to synchronize parental care, Nature Communications (2016). DOI: 10.1038/ncomms11035 Abstract The high energetic demand of parental care requires parents to direct their resources towards the support of existing offspring rather than investing into the production of additional young. However, how such a resource flow is channelled appropriately is poorly understood. In this study, we provide the first comprehensive analysis of the physiological mechanisms coordinating parental and mating effort in an insect exhibiting biparental care. We show a hormone-mediated infertility in female burying beetles during the time the current offspring is needy and report that this temporary infertility is communicated via a pheromone to the male partner, where it inhibits copulation. A shared pathway of hormone and pheromone system ensures the reliability of the anti-aphrodisiac. Female infertility and male sexual abstinence provide for the concerted investment of parental resources into the existing developing young. Our study thus contributes to our deeper understanding of the mechanisms underlying adaptive parental decisions.


News Article
Site: http://www.greentechmedia.com/articles/category/solar

After a short dip in activity in 2013, the construction of large-scale solar power plants is leading the boom for America's solar industry. There are now 7,000 megawatts of solar projects sized over 1 megawatt planned for development in the U.S. over the next year, according to GTM Research. Roughly 1,300 megawatts of those projects have signed contracts that will begin in 2017, after the assumed deadline for a reduction of the federal Investment Tax Credit. Companies building those projects are speeding up development in an effort to capture the 30 percent ITC, and thus opting to bridge the financing gap themselves for a year. It's yet more proof of how important 2016 will be for the solar industry. The solar industry shouldn't just be focused on putting up record numbers. It should be focused on ensuring every single megawatt is built to the highest standards, using the best equipment, in order to deliver the most competitive projects possible. There are many stages of bankability when building a solar power plant. They include design, equipment procurement, installation and commissioning, and maintenance. From the inverter to the transformer to the substation, equipment procurement influences all of these areas in powerful ways. Solar developers understandably focus on levelized cost of energy. But when factoring in all these stages of bankability -- with equipment selection informing every stage -- a project is better measured by total operating costs. We've already discussed how inverters fit into this picture. Let's take a look at another vital piece of equipment for projects: transformers. It takes significant lead-time to find the right site, file the necessary permits, and start designing the project. Thinking about transformer requirements at the earliest stages of development is critical to ultimate success. Timeliness is one key reason. Developers with projects in the beginning stages can easily prearrange an order with a manufacturer like ABB to secure production slots for a very minimal upfront price. That enables the equipment manufacturer to deal with shifting time constraints and move production as needed on their schedule. The longer the dialogue stays open with the supplier, the easier equipment design and delivery becomes. This early engagement also helps the developer fully evaluate whether a transformer is properly tested, designed and suited for the specific solar project requirements. If the time-constrained customer chooses equipment based only on price at the last minute, they run the risk of getting the product delivered late -- and possibly getting a transformer that won't perform optimally over the lifetime of the system. It's also important to anticipate delivery logistics and last-minute design changes. "Thinking about these types of issues can save lots of headaches during installation, when you are under substantial time constraints," said Jay Sperl, a regional business manager for transformers at ABB. Technical factors are another reason to engage with equipment suppliers like ABB early in order to make installation easier, faster and less costly over the life of the project. ABB designs transformers specifically to match the characteristics of an inverter by working closely with manufacturers to understand load characteristics. This dictates simple things like the number of windings involved, and also more complex design characteristics such as how to couple inverters in a pad-mount or substation-like design. There are also ways that pads can be pre-integrated into the transformer, transported, and then put in place on a gravel bed. This can save lots of installation headache if a time-constrained developer does not want to wait for pouring concrete. All of these issues can easily be addressed upfront when designing the project and reaching out to suppliers. They can mean the difference between one week of installation and three weeks of installation. "If you start with the end in mind, what will the equipment look like? What can we do to avoid having surprises later? That will help you engage with suppliers to get an understanding of particular needs in order to benefit you," said Mike Engel, industrial market manager for transformers at ABB. The actual production of a transformer might take a couple of months. The longer lead times come from design and technical review with the customer. Much of the hard work can be done far in advance if the developer engages with the supplier early in the process. Thinking ahead and engaging with suppliers early will also help in the installation and commissioning process. Solar is an elegant technology. But it still takes a complex set of components and logistics to ensure a smooth installation and operation. The equipment supplier should be intimately familiar with all steps in the development cycle. ABB designs every component of a transformer for a specific application, giving the developer a solution with a better lifecycle cost, not just a lower first cost. Over the last few years, ABB has built the elements necessary to bundle a complete solution -- dry- and wet-type transformers, inverters, wireless communications, automation, cybersecurity and installation -- to give customers a turnkey service for solar project developers. Logistics are as crucial as the design itself. If a developer builds a solar plant in a location with harsh weather conditions, components left sitting around the site for too long could get ruined. By optimizing every part of the equipment design and delivery process, ABB can ensure products get to a site when they're needed. This is yet another reason to think about equipment procurement very early in the development cycle. "That's a big part of the benefit ABB brings. We can supply the engineering, the product delivery, the commissioning and the post-installation operation," said Doug Voda, the global segment leader for smart grid medium voltage unit at ABB. A lot is going right for solar in America at the moment. Development activity is at an all-time high and the resource is increasingly competitive with conventional alternatives on an economic basis. In order to ensure a successful 2016 and a transition to a 10 percent ITC, it's imperative that developers procure their equipment with the entire design, installation and commissioning process in mind. "There's always a tremendous push in the fourth quarter of every year. Next year will be even heavier. We understand how the market works and the hurdles developers have to deal with. We can help them work through those at an early stage for a very minimal cost to ensure timely delivery," said Engel. Watch how ABB designs transformers to ensure operational excellence and timely delivery: -- Evaluating the Inverter: Making Sound Equipment Decisions Before the ITC Stepdown


Nature Materials. doi:10.1038/nmat4590 Authors: Ron Feiner, Leeya Engel, Sharon Fleischer, Maayan Malki, Idan Gal, Assaf Shapira, Yosi Shacham-Diamand & Tal Dvir


News Article | August 22, 2016
Site: http://www.nature.com/nmat/current_issue/

Nature Materials. doi:10.1038/nmat4662 Authors: Venkatraman Gopalan & Roman Engel-Herbert New findings suggest that the mechanical stretching of layered crystals can transform them from a polar to a nonpolar state. This could spur the design of multifunctional materials controlled by an electric field.


News Article | April 3, 2016
Site: http://motherboard.vice.com/

43 years ago today, on April 3, 1973, a Motorola engineer named Martin Cooper made the first cell phone call. At the other end of the line from his 2.5 pound Motorola Dyna-Tac prototype was Cooper's chief rival, Joel S Engel, the head of Bell Labs. "Joel, this is Marty," Cooper said, according to a 2013 interview with the BBC. "I'm calling you from a cell phone, a real handheld portable cell phone." "Portable" is relative, of course. The Dyna-Tac was as big as it was heavy: 9 x 5 x 1.75 inches. Packed inside of this shoebox were 30 circuit boards and a battery with about a half-hour of talk time that required 10 hours of recharging. It had no display, and offered only three features: talk, listen, dial. It was, in a word, dumb. But it worked. The Dyna-Tac had by then already gone through some FCC testing in Washington, DC, and, on the big day, Cooper was to demonstrate the phone to a press conference at the Manhattan Hilton. Motorola was at the time trying to convince the FCC to allocate more frequency bandwidth to companies trying to commercialize the nascent technology. Hence, the PR push. Before heading upstairs to the conference, Cooper decided that he'd better make sure the damn thing worked first. "He picked up the two-pound Motorola handset called the Dyna-Tac and pushed the 'off hook' button," a 2000 New York Times interview with Cooper recalls. "The phone came alive, connecting Mr. Cooper with the base station on the roof of the Burlington Consolidated Tower (now the Alliance Capital Building) and into the land-line system. To the bewilderment of some passers-by, he dialed the number and held the phone to his ear." The DynaTAC 8000x, the world's first cellular phone, modeled after the prototype Cooper used. Photo: Motorola Archives Read more: The First Cell Phone Call Almost Got Bloody By that time, the primitive idea of mobile telephone communications was actually quite old. AT&T had first commercialized a variation in the 1940s called Mobile Telephone Service, which was based on VHF radio communications, the range of frequencies more commonly employed for two-way radio use and television and radio broadcasts. Only a small slice of VHF channels were available to the service and collisions between transmissions were a common and prohibitive occurrence. MTS was essentially a form of two-way radio communication with an operator in the middle that bridged landline callers with mobile callers. A "call" would be announced not by a ring, but by the voice of an operator over the radio saying that they had a call for that specific user. Every user would hear every incoming call and the idea was that they just ignored the ones that weren't for them. The hardware required for MTS also weighed about 80 pounds. Real portability would have to wait for the advent of cellular communications. Here, users can be passed between base stations and frequencies can be continually reused. In addition to truly portable hardware, this means that users can reasonably move around from place to place with some guarantee of service. In the 2000 Times interview, Cooper offered a prediction: "Cellular was the forerunner to true wireless communications. And just as people got used to taking phones with them everywhere, the way people use the Internet is ultimately going to be wireless. With our technology, you will be able to open your notebook anywhere and log on to the Internet at a very high speed with relatively low cost. At the moment, our story is about what a relatively small company is doing with high-tech stuff in Silicon Valley." ''But when people get used to logging on anywhere," he added, "well, that's going to be a revolution.''

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