20 Photos Tags Share your voice This seagull tried to snatch my shrimp in Illinois. Amanda Kooser/CNET A pleasant meal beside a scenic body of water can quickly turn into an Alfred Hitchcock movie if you’re not careful. Seagulls are notorious for strolling right up to people and stealing their lunches. But the good news is you might be able to battle this avian crime wave with a simple tool: your eyes.Researchers at the University of Exeter in the UK wanted to know if staring at seagulls might dissuade them from abducting your dinner, so they headed to coastal towns in Cornwall.The team put a bag of chips (that’s fries for us US folks) on the ground and monitored how long it took the gulls to approach the food. “On average, gulls took 21 seconds longer to approach the food with a human staring at them,” the university said in a release on Tuesday.The researchers initially tried to test 74 herring gulls, but most of them weren’t interested in sticking around or stealing food, so only 19 gulls were usable for the study. 1 Comment Watch a leviathan of a shark nibble on a sub’s speargun Oh snap! Weird ocean worms make a racket when they rumble Cool critters “Gulls are often seen as aggressive and willing to take food from humans, so it was interesting to find that most wouldn’t even come near during our tests,” said Madeleine Goumas, lead author of the study Herring gulls respond to human gaze direction, published in the journal Biology Letters.The researchers found that individual gulls behaved very differently from each other. Goumas suggested “a couple of very bold gulls might ruin the reputation of the rest.”The study had a small sample size, so your gull-staring mileage may vary. It’s worth a shot, though. If you want to protect your food and still enjoy your time at the seaside, then it may just be a matter of playing stare down with the local birds. A spider’s erection, and other cool things trapped in amber Sci-Tech
Esther Dyson/Flickr Getting ready to explore Texas this weekend? Planning your getaway can be a whole lot easier with apps you can download to your smartphone or tablet before hitting the road.The Trip.com app lets you design your own itinerary, from booking a hotel, checking out local events and dining options and leaving a review when you’re done. You can tailor your experience with the app by selecting your interests – they call them tribes. Are you looking for family-oriented activities, something artsy or maybe nightlife? Simply select the relevant interests for your excursion, and the app will customize suggestions for you.Foodies and picky eaters alike will love Trip.com’s restaurant ideas. To learn more about a restaurant, just click its listing. You can view hours of operation, and take a look at the menu. Some restaurants give you the option to book a table right from the app. When you’ve decided where you want to go, tap the map. It’ll automatically route you there from your current location.You can earn “scout status” by creating a few postcards from the pictures of your adventures on your phone.Want to live like a local? Try the Airbnb app. Live in someone’s home, condo or apartment rather than a hotel. In some homes, you can cook for yourself instead of dining out for every meal. This is especially great when you’ve got the kids in tow. Some less expensive Airbnb options include renting one room in a larger house while the owners are still in residence. Really, you just have to decide what works best for your needs.If you travel a lot, check out TripIt. It keeps all of your hotel reservations and confirmations – your flights, and anything else you may need, all in one convenient place. Real-time updates mean that if something changes, you’ll be alerted right away. If there’s a flight delay, a gate change or a cancelled flight, you’ll get a notification from Tripit. It’s a free app but you can upgrade to Tripit Pro for more features.Spend less time planning and more time enjoying on your weekend trips. Share
It’s the time of year when teens in the Washington D.C. area search for the fanciest gowns, buy the swankiest suits or rent the classiest tuxedos: it’s prom season! Unfortunately, many teens in the area can’t financially afford to look as elegant as they want. CBS Radio station WPGC 95.5 and non-profit organization Once Upon a Prom stepped up to that challenge by providing hundreds of teens across the region with free prom attire at their sixth annual Operation Pretty and Polished event. WPGC, along with El Zol 107.9 radio, partnered with State Farm for the six-hour event hosted by reality television star Paul Wharton on May 3 at the Boys & Girls Club of Greater Washington in northeast Washington, D.C. Throughout the year, everything from gently used dresses to suits, shoes and accessories are collected and housed at various State Farm locations. With much anticipation, local teens and their parents waited in line beginning at 7 a.m. for the doors to open. Students were given a number, based on their arrival time, to choose their prom gear in an orderly manner. “I was excited to give back and be a part of this [event],” said Wanda Jenkins, Miss University of the District of Columbia 2013-2014. “The cost of shoes, a gown, and make-up is expensive.” “I told the girls and boys to remember this day and [remember] who helped them with prepare for their prom and give back when they get older,” she added. With more than 1,000 garments to choose from, some students attending their eighth grade junior prom or their 12th grade senior prom felt overwhelmed with the huge selection. Shae, 17, said she was simply looking for a red dress for Suitland High School’s senior prom. After trying on four red gowns, the senior could not decide what to take home. Female celebrity shoppers included Jenkins, Miss Maryland Jr High 2014 Michaela Smith, recording artist Tulani, Tati of WPGC’s Pablo Morning Show, on-air personality Sunni and the City, and ladies of the WPGC Street Team assisted the girls in finding the right look. Former Washington Redskins player Josh Morgan, now with the Chicago Bears, and the Redskins’ Trent Robinson assisted the young males in their fashion quest. Celebrity shopper and former Mrs. Maryland 2011 Sandra Bryan-Grier donated 73 gowns, 15 pairs of shoes, 25 pairs of earrings, 15 new adhesive bras, and 13 purses from SanSan Closet, her non-profit organization. “[Going to the] prom is [the beginning of] crossing over to adulthood so it’s important for them [students] to have that experience,” she said. “It’s important for them to go and think back. It’s a memory that’s long-lasting.” Once Upon a Prom founder Jackie Johnson said she was amazed by the continuous support received this year, and every year. To assist the young gentlemen financially, Men’s Warehouse offered tuxedo rentals at $59.99, discounted from their regularly priced $150 to $180 rentals. While the anxious teens shopped with their celebrity shopper, their parents received giveaways and free blood pressure, body mass index and diabetes screenings courtesy of MedStar and Chi Eta Phi nursing sorority. They also enjoyed the sounds of harpist and singer Tulani, who has toured with Lady Gaga. Colleges and universities including the University of District of Columbia, Georgetown and Trinity were also on hand, urging students to consider enrolling into college and discussing life after the prom.
Journal information: Proceedings of the National Academy of Sciences Entanglement can help in classical communication (Phys.org)—As developed by Claude Shannon, information theory defines channel capacity as the maximum rate at which information can be sent through the channel. This capacity can be mathematically described using a graph associated with the channel. Specifically, a graph’s Shannon zero-error capacity is the maximum rate at which messages can be sent through a noisy channel with zero probability of error. However, the Shannon capacity does not reflect the fact that on atomic scales, nature behaves according to quantum mechanics. Recently, scientists studying asymptotic behavior in entangled sender-receiver quantum systems at Centrum Wiskunde & Informatica, The Netherlands have identified families of graphs for which entanglement allows the Shannon capacity to be exceeded. Therefore, Briët points out, in the above example the sender could send any one of ten different messages with zero probability of error. Moreover, he adds, their main result shows that this number can be larger than the average number of messages that can be sent with zero error if no entanglement was used, thereby exceeding the zero-error Shannon capacity.”To show that entanglement can sometimes allow a sender and receiver to communicate more efficiently,” Briët continues, “one needs to create a channel for which one can prove that the entanglement-assisted capacity is large, but the Shannon capacity is small. However, proving good bounds on these parameters is notoriously difficult. It took over two decades and a brilliant mathematician to compute the Shannon capacity of the pentagon, which is the graph associated with a particular channel that has only five inputs and outputs! Only for a very few special cases can we currently say something non-trivial about these parameters.”The challenge then, says Briët, was to find a “sweet spot” among these special cases where the researchers can prove good bounds on both the entanglement-assisted and Shannon capacities. They looked at a particular class of graphs often used in quantum computing and information theory – so-called orthogonality graphs – that show that entanglement or some other quantum resource can make some classical information processing task easier. (In an orthogonality graph, points in a two, three or higher-dimensional space are labeled by arrows; a pair of such points are labeled by a line if the associated arrows are orthogonal – that is, in perpendicular directions.) “In this sense,” Briët notes, “these graphs were natural candidates for the type of result we were after. Using available techniques it is a fairly straightforward calculation to show that the orthogonality graphs have very large entanglement-assisted capacity – but it was unknown, and it still is, if the Shannon capacity is any smaller.”Their key insight, Briët says, was that they could slightly morph the orthogonality graphs to end up a class of graphs that lie in the kind of the previously-mentioned sweet spot. “Essentially, what we did is take one of these graphs and throw away three-quarters of it, not just any, but such that we are left with a quarter that has enough structure for us to be able to bound the two capacities. In addition, to bound the two capacities we had to use two quite different techniques.” To show that their graphs had very high entanglement-assisted capacity, they borrowed ideas from geometry, while to show the graphs’ low Shannon capacity they tapped algebra.”To argue that entanglement should be used to speed up communication in practice, our results would need to be strengthened,” Briët acknowledges. “In our setting we made stronger assumptions on how tolerable a little noise is than is reasonable in real-world situations. A next step would be to weaken these assumptions, for example to one where the receiver is happy if he can narrow down what the sender was trying to transmit to a small list of possibilities, as opposed to receiving the messages without ambiguity.””There are close links between entanglement-assisted communication and physical experiments that are meant to test if quantum entanglement is actually a real phenomenon,” Briët notes. “It’s predicted to exist by quantum mechanics, but since that’s only a mathematical model of how nature could work, this doesn’t mean that it has to exist. Convincing experiments were already performed in the early eighties, but because experimental set-ups are bound to have small defects, skeptics argue that no hard conclusion can be drawn from them. Physicists are still trying to come up with ever-better and better experiments that are robust against such defects,” Briët concludes, “so that even if they are taken into account one cannot argue that the results could have been produced if entanglement wasn’t present in the experimental set-up.” Explore further Copyright 2013 Phys.org All rights reserved. This material may not be published, broadcast, rewritten or redistributed in whole or part without the express written permission of Phys.org. Citation: Never mind the noise: Quantum entanglement allows channel information rate to exceed Shannon zero-error capacity (2013, January 23) retrieved 18 August 2019 from https://phys.org/news/2013-01-mind-noise-quantum-entanglement-channel.html This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only. More information: Violating the Shannon capacity of metric graphs with entanglement, PNAS published online before print December 24, 2012, doi:10.1073/pnas.1203857110Related: 1Entanglement-assisted capacity of a quantum channel and the reverse Shannon theorem, IEEE Transactions on Information Theory Volume: 48, Issue: 10 Page(s): 2637-2655 Oct 2002 Dr. Jop Briët discussed the challenges he and his colleagues, Dr. Dion Gijswijt and Prof. Harry Buhrman, encountered in determining if for a family of graphs, the entanglement-assisted capacity exceeds the Shannon capacity. (A graph has as many points as there are inputs to the channel. Such a graph is usually referred to as the channel’s confusability graph, because two points are connected by a line if they can be confused with each other when one of them is sent through the channel.) “The two parameters that we wanted to separate – the Shannon capacity and the entanglement-assisted capacity – are similar in the sense that they indicate how effectively one can communicate over a noisy communications channel,” Briët tells Phys.org. “In the entanglement-assisted case the sender and receiver have an extra resource – quantum entanglement – so the latter parameter is always at least as large as the former.” Briët points out that in the two extreme cases these parameters are actually equal: If the communications channel is perfect (i.e., noiseless), entanglement gives no advantage at all. On the other hand, entanglement cannot improve this situation if only a single message can be sent with zero error.In entanglement-assisted communication, Briët explains, there are two parties (sender and receiver) and two resources (a noisy communication channel and a pair of entangled quantum systems). The sender has one of the systems and the receiver the other, and the two parties can perform measurements (that is, experiments) on their respective quantum systems. While the outcomes of such experiments can usually not be predicted in advance, making measurements on entangled systems can still lead to useful results because outcomes of an experiment done by the sender and an experiment done by the receiver, though random, can be strongly correlated. “The entanglement-assisted communication protocol we consider,” Briët adds, “dates back at least as far as the work of Charles Bennett and others1 in 2002.”Suppose the sender can do ten different experiments, labeled with the numbers 1 to 10, and suppose that the possible inputs to the channel are the letters of the alphabet A to Z, Briët illustrates. The sender picks an experiment (for example, experiment number three), and depending on the outcome sends one of the letters – in this example, the letter P – through the channel to the receiver. Because the channel is noisy, the receiver gets a symbol that could be a P, B, D, or R. Based on this list of four letters the receiver chooses an experiment to perform on his quantum system and associates a number between 1 and 10 with each of the possible outcomes. “The punchline,” Briët says, “is that it’s sometimes possible to set things up so that the only possible outcome of the receiver’s experiment is the number of the experiment done by the sender – in this case the number three.” (i) Channel with five inputs (numbers) and five outputs (letters), where an input symbol x is connected to an output symbol a if P(a|x) > 0. Notice that none of the five pairs (0, 2), (1,4), (2,1). (3,3), (4,0) can be confused with one another, as either the first or the second two symbols are nonconfusable. (ii) Confusability graph of the channel, the five cycle C5. Copyright © PNAS, doi:10.1073/pnas.1203857110
Since approximately 1990, it has been relatively easy to measure sea level height across the planet because of advances in satellite technology. Prior to that time, as the researchers note, it was much more difficult due to a variety of factors such as gravity, land rising and sinking, wind patterns, etc., using tide gauges placed at sites around the world. In this new effort, the researchers have attempted to gain a better understanding of sea level changes during the 20th century prior to the use of satellite technology.To create a better record, the researchers collected tide data and combined it with factors that are known to have caused changes in sea levels, such as shifts in land masses, regional events such as weather changes and, of course, runoff due to melting of glaciers and northern ice. They used all the data they had collected to create a model depicting sea levels in various parts of the world over the past 100 years, and then used the model to calculate the rate at which sea levels were rising on average over the same time frame. As expected, the model showed a rate of 3.1 millimeters per year since 1990, which agrees with satellite reports. But the model also showed that before 1990, the average rate was just 1.1 millimeter a year, which is significantly less than other models have shown. These numbers suggest that sea levels have been rising much faster since 1990 than other models have shown, in some cases up to three time faster.The accelerated rise is believed to be due to more runoff from mountain glaciers, expansion of ocean waters due to warmer water temperatures, and melting of ice in the northern and southern parts of the planet—all due to global warming. (Phys.org)—A team of researchers from across Europe has found evidence that suggests the rate of rise in sea levels from approximately 1902 until 1990 was less than other models have shown. This indicates, the team reports in their paper published in Proceedings of the National Academy of Sciences, that modern sea levels are rising faster than suspected. © 2017 Phys.org Journal information: Proceedings of the National Academy of Sciences Explore further More information: Sönke Dangendorf et al. Reassessment of 20th century global mean sea level rise, Proceedings of the National Academy of Sciences (2017). DOI: 10.1073/pnas.1616007114AbstractThe rate at which global mean sea level (GMSL) rose during the 20th century is uncertain, with little consensus between various reconstructions that indicate rates of rise ranging from 1.3 to 2 mm⋅y−1. Here we present a 20th-century GMSL reconstruction computed using an area-weighting technique for averaging tide gauge records that both incorporates up-to-date observations of vertical land motion (VLM) and corrections for local geoid changes resulting from ice melting and terrestrial freshwater storage and allows for the identification of possible differences compared with earlier attempts. Our reconstructed GMSL trend of 1.1 ± 0.3 mm⋅y−1 (1σ) before 1990 falls below previous estimates, whereas our estimate of 3.1 ± 1.4 mm⋅y−1 from 1993 to 2012 is consistent with independent estimates from satellite altimetry, leading to overall acceleration larger than previously suggested. This feature is geographically dominated by the Indian Ocean–Southern Pacific region, marking a transition from lower-than-average rates before 1990 toward unprecedented high rates in recent decades. We demonstrate that VLM corrections, area weighting, and our use of a common reference datum for tide gauges may explain the lower rates compared with earlier GMSL estimates in approximately equal proportion. The trends and multidecadal variability of our GMSL curve also compare well to the sum of individual contributions obtained from historical outputs of the Coupled Model Intercomparison Project Phase 5. This, in turn, increases our confidence in process-based projections presented in the Fifth Assessment Report of the Intergovernmental Panel on Climate Change. Citation: Sea level rise prior to 1990 found to be slower than other estimates suggesting modern rise significantly faster (2017, May 23) retrieved 18 August 2019 from https://phys.org/news/2017-05-sea-prior-slower-modern-significantly.html Researchers model differences in East Coast sea level rise Credit: CC0 Public Domain This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.