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Flowers Create ‘Electric Landing Lights’ for Bees

first_imgHow do bees know which flowers to visit, and where on the flowers to land?Visual cues are part of the answer. It has already been known that bees and other insects see flowers differently than humans do. Bees can sense both visible and ultraviolet light, and many flowers have markings in both wavelength (color) bands, which help to both attract pollinating insects from a distance, then guide them in to the center areas where they can find the nectar (and at the same time pollinate the flower).  Bees can also detect plumes of fragrance from flowers.It was also previously known that flowers have a slight negative electrical charge, whereas bees pick up a slight positive charge by colliding with dust particles while flying through the air. It had previously been observed with high-speed video that just before a bee lands on a flower, the positively-charged pollen particles on the bees’ legs jump across the gap and stick to the negatively charged flower.New research published in Science Magazine shows that flowers have specific electric field patterns pointing the way to their center where the nectar is located. As we recently highlighted from a related paper in PNAS (6/08/16), the tiny hairs on the legs of bees can sense electrical charges, such as these electrical patterns on flowers.To test bees’ responses to the flowers’ patterns, researcher Dominic Clarke and his team created artificial flowers with a ‘bulls-eye’ electric field pattern and filled them with sugary nectar, while filling identically-colored artificial flowers with a generic electric charge with a bitter liquid. In their experiment, bees quickly learned to go exclusively to the patterned flowers (70% accuracy). When the electric fields were turned off, the bees could no longer tell the flowers apart.To view the flowers’ electric fields, the researchers sprayed brightly-colored positively-charged particles on the flowers, then took photographs.  (Beautiful photographs are viewable at National Geographic‘s article.Not only do the flowers provide these ‘electric signs’ for the bees, their voltage also changes in time to provide further guidance for the bees. Immediately after the bee lands on a flower, its negative charge decreases by 25 millivolts, and it stays reduced for about two minutes. This difference in electric field for recently-visited flowers may help bees sense which flowers have not been visited in a while, thus hold more nectar.How could this intricate mutually-beneficial system evolve?  Which came first, the bees’ system of leg hairs, neural connections, and neural processing to sense and understand the electric fields, or the flowers’ system of more- and less-conductive anatomical patterning that points the way to their nectar, and the flowers’ finely-tuned passive or active system for adjusting its voltage signal in real time?Evolutionists like to claim that in such “irreducibly complex” systems, each part must have had some other function at some time.  Fine – let them show this.  As Darwin wrote, “If it could be demonstrated that any complex organ existed, which could not possibly have been formed by numerous, successive, slight modifications, my theory would absolutely break down.”In order for this symbiotic electric field ‘dance’ to be beneficial to either species, all the parts had to work together. A genetic mutation that changed flowers’ electric fields would be useless if pollinators could not sense them, and would be selected against because of the wasted energy involved. Likewise, a mutation that gave bees hairy legs would be useless and wasteful without the neural processing circuits to understand the hair signals. Neurons growing down into bees’ legs and neural sensory-integration centers without sensor hairs would also be useless.Instead, it makes more sense to view these interacting species as having been designed for each other by God. Two unique species ‘serving’ each other and helping each other in mutually-beneficial ways is precisely the type of beautiful interaction we would expect, based on the character of the God of the Bible.[Guest article by an engineering professor](Visited 59 times, 1 visits today)FacebookTwitterPinterestSave分享0last_img read more

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‘Alive with investment possibility’

first_img“Investors dream of a business destination which combines their ideals: the stability of a developed nation, the opportunity of a vibrant emerging market, and a climate that fosters growth.“It’s time to take a closer look at South Africa.”Throughout June 2005, coinciding with a high-level investment mission to Europe, the International Marketing Council aired a short documentary on South Africa as business destination on CNBC Europe’s influential World Business programme.The documentary, featuring testimonials from global investors who have had success doing business in South Africa, also ran on 10 leading international airlines for the entire month. Online video streaming ‘Investors dream …’ (video transcript):Investors dream of a business destination which combines their ideals: the stability of a developed nation, the opportunity of a vibrant emerging market and a climate that fosters growth.Its time to take a closer look at South Africa. Niall Fitzgerald, chairman of Reuters: “South Africa has to be one of the most attractive investment destinations in the world just now. After all, it’s got low costs, great climate, hugely creative people supported by an economy which has been skillfully mananged – and it’s the gateway to 200 million people in southern Africa.”The Dialogue Group finds the South African workforce, timezone and world-class telecommunications the perfect combination for call centres.BMW and other leading automotive brands thrive under South African skies, gaining global recognition for quality and exporting vehicles worldwide.Barclays, in sealing its deal to buy Absa bank, affirmed the strengh, sophistication and potential of South Africa’s financial systems by investing in the country’s largest ever foreign direct investment deal.Dominic Bruynseels, CEO of Barclays Africa and Middle East: “It’s a huge vote of confidence. We think South Africa is a positive and growing economy, and we want to be a part of that.” Trevor Manuel, South African minister of finance: “We’ve taken some very tough decisions to provide a climate for certainty. The Constitution, the legal framework, the macro-economic framework, all add up to certainty and predictability.“South Africa has created a climate that investors need.”Supported by the government’s $8.5-billion investment in infrastructure, South Africa is committed to reducing the cost of doing business, and to maximising the value of its strategically located ports, which link three continents.Embrace this opportunity. Be part of this country that is Alive with Possibility.Source: International Marketing Council of SAlast_img read more

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Do Violent Video Games Really Cause Violent Behavior?

first_img Tags:#gaming#politics#research 9 Books That Make Perfect Gifts for Industry Ex… Related Posts After the recent tragedy in Newtown, CT, some commentators and – notably – the National Rifle Association (NRA) remarked that video games played a role in a “culture of violence” and detachment that can ease the path to violent behavior. This, in turn, has given new life to the debate about the role of media violence – particularly, violent video games – on real-world aggression. It’s a serious topic, so ReadWrite thought it was important to to recap the latest on the discussion and see where scholarly studies and popular opinion fall.Understanding The NumbersWe all know the guy who plays Call of Duty eight hours a day, then goes home to a world of puppies and rainbows. We’ve also heard of the kid who plays a game for an hour or two, then goes on a shooting spree. There are exceptions to any rule, and if we’re going to find real answers, we need to look at trends and averages, not statistical outliers.It’s also important to remember that even if there is a link between violent games and aggressive behavior, that does not imply causality. Violent criminals may well choose violent games, but tens of millions of gamers play those games every week, and the vast majority are law-abiding, normal citizens.At the same time, it might be shortsighted to ignore such links. According to a recent publication by Iowa State University professor Dr. Craig Anderson, “Correlational studies are routinely used in modern science to test theories that are inherently causal. Whole scientific fields are based on correlational data (e.g., astronomy). Well conducted correlational studies provide opportunities for theory falsification. They allow examination of serious acts of aggression that would be unethical to study in experimental contexts. They allow for statistical controls of plausible alternative explanations.” In other words, short of placing a subject in a dangerous situation, correlation is often the best evidence available, and it can be useful debunking other theories.The State Of ResearchAt the moment, studies are all over the map, largely because just about every study of video game violence uses different definitions of the terms. The Legend of Zelda, Grand Theft Auto and Missile Command are all violent games in their own ways, but they’re not at all similar. Likewise, throwing a fake roundhouse kick at your buddy, checking a box describing “elevated feelings of aggression,” and setting fire to a building are all extremely different violent expressions. Unfortunately, current studies span both spectrums, so anyone with a vested interest can easily find a study to support their position. Worse, this makes meaningnful meta-analysis across multiple studies is effectively impossible. 80% of studies agreeing with a certain position doesn’t mean much if half of those studies were poorly structured and the other half were measuring something completely different.5 Emerging TruthsWith that said, there seem to be five theories gaining traction. Each has its naysayers, of course, but they have real data to back them up: cormac foster 4 Keys to a Kid-Safe App 5 Outdoor Activities for Beating Office Burnout 1. At-Risk Populations Are Vulnerable To Violent StimuliOne popular theory holds that some people are more vulnerable to the effects of gaming violence than others. This resonates with our gut instincts, and provides a happy, reasonable-sounding middle ground for both sides. In the Review of General Psychology, Drs. Patrick and Charlotte Markey outline the three most predictive traits for vulnerability:high neuroticismlow agreeablenesslow conscientiousnessThis doesn’t mean that games cause violent behavior. It suggests that violent games are among the many influences that can be linked to violent behaviors. We’ve seen copycat murders modeled after television newscasts, Mark David Chapman’s obsession with The Catcher in the Rye, and thousands of years of killings based on stories from holy works. Violence and rebellion in media have always been lightning rods for the mentally ill, and video games are a popular medium for the young male demographic most likely to commit violent acts.The upshot? Young people who are emotionally upset, detached or combative, and impulsive should probably not be exposed to violent games. Unfortunately, that describes a fair portion of teenagers, so use discretion applying the rule to your own kids.2. Video Game violence Is Not A Significant Danger To The General PopulationEven the most damning studies don’t claim that video games will create violent monsters of your children. They can’t. If that were true, we’d have blood running in the streets. For the majority of “normal” gamers, the worst claims seem to be short-term aggression without substantial consequence, and a general lessening of communication and empathy skills – but again, without specific consequences attached.The majority of research on the subject seems to indicate a fairly tenuous link between in-game and real-world violence. For example, two studies conducted by Texas A&M and the University of Wisconsin – Whitewater, respectively, found no conclusive evidence. “Structural equation modeling suggested that family violence and innate aggression as predictors of violent crime were a better fit to the data than was exposure to video game violence.”In other words, a predisposition to violence or a violent homelife is very likely a predictor of future violent behavior, while video games are not.3. Fantasy Violence Is Less Dangerous Killing Falatacot Raiders won’t make you murder humans, though we’re not sure about Hitman. Some people have pointed to studies showing that even E-rated games can lead to imitation (e.g., children punching or kicking) for a period following play, but it appears that transference of aggression from aliens, orcs, or Pokemon to humans is minimal, at worst.4. Violent Games Do Increase SimulationJust like watching action movies or sprinting down a street, violent video games (and other competitive or action games) increase stimulation and adrenaline production, which can produce short-term disruptions and enhanced moods. Some studies claim short-term affects can last long enough to disrupt sleep when played before bedtime, while others saw certain effects lingering up to 24 hours. At the very least, the “amp up” factor is real – it’s kind of the point. For parents of children who may be particularly affected by such things (e.g., those with Attention Deficit Hyperactivity Disorder, or ADHD), this can be a concern.5. Content Ratings MatterPeople on both sides of the issue agree that content ratings are important. Even absent a long-term impact on violent behavior, graphic scenes of violence, nudity and other adult situations can impact developing minds. Video game access should be restricted like access to any other type of media.The Easy AnswerAnyone who wants the government to step in and make the call on what to do about video game violence will be sorely disappointed. There simply isn’t enough evidence linking video games and violence to even start that discussion, particularly when films and images of far more graphic violence are readily accessible.The answer to the problem seems to be the same as the answer to concerns about TV rotting your kid’s brain in the 1960s: personal responsibility. If you’re a parent, pay attention to the ratings, research the content of games online before you buy them, and above all, know your child’s sensitivities and limitations. If you’re in doubt about the effect of a game or other piece of media, say no.That won’t end the debate, of course. Truly troubled teens often don’t have the parental supervision they need to limit their gaming or other media consumption. But it’s unclear exactly what the right strategy would be to deal with that issue. 12 Unique Gifts for the Hard-to-Shop-for People…last_img read more

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