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The main problem with MAVs has to do with the way they respond (or don’t respond) to dynamic environments--things like shifting or gusting winds, moving bodies, and other variables that have to be accounted for in realtime. MAVs are tiny, so there’s not a lot of space for computing assets or sensor payloads, and that leads to a sort of intractable problem: how can engineers make these things smaller and more capable while also adding increased situational awareness and better in-flight processing?

When facing a tough problem like this a little biomimicry never hurts, and that’s exactly where the Pentagon is looking with its recent contracts. If two research stipends recently handed down are any indication, the micro-drones of the future may have tiny hair-like sensors all over their bodies and big, compound eyes.

The cilia-like hairs will serve to keep the drones’ hovering and flight stable by sensing changes in air flow at the tiniest levels. That means the drone could sense a wind gust coming shortly before it arrives, allowing it to compensate for the change in circumstance. It would also aid in maintaining overall stability during flight, as the MAVs central processor would possess a constant awareness of--and the ability to manipulate--the boundary flow layer of air surrounding the drone as it hovers and flies.

The bug-like compound eyes would similarly help MAVs navigate in cluttered spaces by increasing the amount of visual data available to the drones’ processors. An on-board minicomputer would process images in realtime, using those visual cues to automatically avoid obstacles and navigate cleanly and efficiently.

[Danger Room]

Female mosquitoes mate only once in a lifetime, and then store the male's sperm to be used as needed throughout the rest of her life. What's important about the new findings, which appear in the Proceedings of the National Academy of Sciences journal, is the discovery that the females do not seem to distinguish between sterilized males and fertile males--they mate only once, either way. A process that can sterilize males would thus result in a pretty serious decrease in the number of new mosquitoes.

Sterilization isn't new, but it's usually done via radiation, which tends to make male mosquitoes very weak and unable to take part in what the BBC calls a "frenzied" mating behavior. Scientists from Imperial College London devised a way to inject mosquito embryos with a bit of RNA that disrupts one of the genes needed for sperm production, leading to healthy, but sterile, male mosquitoes.

Of course, there are lots of problems with using a system that could decimate an entire species--many other creatures, including our beloved bats, rely on mosquitoes for food, and so wide-scale eradication of mosquitoes isn't generally seen as a viable strategy. But the discovery could still be used to control mosquito population--and as malaria accounts for as many as 20% of childhood deaths in Africa, a controlled population could be invaluable.

[BBC]

Entomologists are submitting suggestions for 5,000 insects and other arthropods whose genomes should be sequenced, in a hunt for vulnerable regions that can be targeted with pesticides. The five-year 5000 Insect and Other Arthropod Genome Initiative, otherwise known as the i5K Initiative, will target insects that are known to be important to worldwide agriculture, food safety and medicine, among other impacts.

The study will examine insects that serve as disease transmitters and close relatives that do not, so researchers can compare genes that make some insects disease vectors and others benign. Certain species of mosquito, for instance, carry diseases like malaria or yellow fever, while other species do not, and understanding the genomic difference could help fight the disease-carrying types.

Pinpointing the genes that cause susceptibility to pesticides could actually help beneficial insects, like bees, while eradicating harmful ones from farm fields. Geneticists could mine data for specific detoxification genes found in certain insects, said Kevin J. Hackett, a national program leader at the USDA Agricultural Research Service, in an interview in the magazine American Entomologist.

“If we know about those genes from one insect to another, we can use that information to actually kill the insects," he said. “Or if you take beneficial insects like honey bees, which do not have as many detoxifying genes and are more susceptible to chemicals, that kind of information could be used to help protect bees.”

The project is feasible now because the costs of genetic sequencing have fallen sharply in recent years. As researchers begin sequencing genomes, they will be available on several public domain databases, entomologists said.

Do you know a lot about bugs, or the troubles they cause? Click here to nominate a species for sequencing.

[via BBC]

The evolving bedbug is back and more infuriating than it's ever been before

In the 1940s and ’50s, liberal use of DDT and other insecticides all but wiped out the pests. Scientists hypothesize that the few that survived proliferated—females can lay up to five eggs a day, and 500 during a lifetime—and passed along pesticide-resistant traits. Millions of bedbug generations later, scientists are finally zeroing in on how, exactly, bedbugs made their comeback.

Thicker Skin

Entomologist Dini Miller of Virginia Tech says bedbugs probably developed thicker, denser, waxlike exoskeletons, also called cuticles, that repel chemicals in pesticides. To test the hypothesis, her group is comparing cuticle-coding genes in both insecticide-resistant and susceptible bedbugs, as well as measuring their cuticle thickness and hydrocarbon content, which indicates how much wax is present. Miller says the results will be published next year.

Faster Metabolism

Contemporary bedbugs produce more P450 enzymes than their ancestors. The enzymes metabolize oily toxins like pyrethroids, the most common chemicals in pesticides, rendering them harmless. Entomologist Subba Reddy Palli of the University of Kentucky and his colleagues have identified at least 100 genes that code for P450s, and changes to any of them could account for the metabolism boost.

Chemical Blocking

Pyrethroids bind to and block sodium channels, paralyzing bugs. Palli’s studies show that 88 percent of bedbugs in the U.S. have mutated to block pyrethroids. “The future is to target something other than the sodium channel,” Palli says, “although eventually bedbugs will adapt again. It’s always a game of catch-up.”

Search and Destroy

When pesticides won’t work, physical removal is the only option. Find the bedbugs’ hiding spots with the help of a professional exterminator or trained dog. Bedbugs typically live where you sleep. Kill the pests by vacuuming them up, along with their shed skins and droppings. Throw all clothes, linens and any other fabrics into the dryer. Coming soon: an improved option for detection, the electronic dog nose.

Nobody has really bothered to study fire ants before, having been generally more interested in cursing at them and running quickly away from them, but a couple of mechanical engineers at the Georgia Institute of Technology noticed some pretty incredible properties upon examination. Turns out fire ants, when in groups, grasp onto each other using their mandibles, forming an intricate and precise pattern something like a Gore-Tex fabric.

This fabric-like bunching is even weirder than it sounds: The group of ants can be molded almost like a thick liquid (Wired compares it to honey or ketchup), and it will retain that shape even when manipulated. To undergo a waterproofing test, the engineers simply spun a bunch of ants in a cylinder, forming them into a near-perfect sphere in the same way you might form a meatball, if you used scientific equipment and not your hands while cooking. These ant-balls, with about 500-8,000 stinging bugs per ball, were dropped into a vat of water, where they assuredly did not drown.

Instead, the ant-ball almost instantly spread out into a raft, enhancing the ants' already hydrophobic waterproofing. Ants can survive for days on the water in this way, never at risk of drowning. In fact, the engineers even poked this ant-raft with a stick (which would have been your first instinct too, don't lie) and found that it was so hydrophobic that it merely bent the surface of the water rather than pushing the ants underneath it.

So how is this useful? Well, given how much we love biomimicry, we could easily see some of the properties of these ants used for commercial fabrics, but the engineers suggest military microbots could have a lot to learn from these ants as well.

Oh, and if you're concerned about a bunch of engineers manhandling, poking, and doing their damnedest to drown these animals, don't be. The fire ants, collected from the Georgia road-side, are a highly overpopulated invasive species in that region, and the engineers say they further "lost sympathy for them" after more than a few bites.

[PhysOrg via Wired]

Researchers at the University of Maryland, who were funded by the National Institutes of Health/National Institute of Allergy and Infectious Diseases, say the method could be an effective treatment against malaria, especially as mosquitoes increasingly evolve to resist insecticides. Even better, the fungus modification can be targeted to almost any disease-carrying insect, potentially allowing fungus-based prevention for maladies like Lyme disease or dengue fever. The study was reported today in the journal Science.

The Metarhizium anisopliae fungus naturally attacks mosquitoes, and it has already been used to reduce disease transmission — but it only works if the bugs are sprayed with fungus soon after they picked up the malaria-causing Plasmodium falciparum parasite. What’s more, the mosquitoes often die before reproducing, leaving fungus-resistant mosquitoes to take over and render the spray useless. So rather than enhance fungi to better kill mosquitoes, entomology professor Raymond St. Leger and colleagues modified the fungi to block the development of Plasmodium in the mosquito.

They used genes for a human antibody and a scorpion toxin, both of which specifically target Plasmodium, and inserted them into the fungus. They fed some mosquitoes a Plasmodium-infected blood meal, and separated them into three groups. One group got a dose of the transgenic fungus, another got a natural fungus and the third was not sprayed at all. Two weeks after the bugs were exposed to the malaria parasite, the researchers checked for its presence in their salivary glands (this is how it’s transmitted to humans).

Spraying mosquitoes with the transgenic fungus significantly reduced parasite development, the team found.

Malaria is found in 106 countries and there are an estimated 225 million malaria cases every year, including 781,000 deaths, mostly in sub-Saharan Africa. Prevention usually involves spraying bed nets and interior walls with pyrethroid insecticide to kill the mosquitoes, but the bugs are evolving to resist it, and there are no promising prospects for a chemical replacement.

Other teams have genetically altered mosquitoes to resist Plasmodium, and modified other mosquitoes to be sterile in order to reduce their populations. But transgenic mosquitoes could pose some ecological problems. A fungal treatment can be modified to keep up with mosquitoes’ natural adaptations, St. Leger said.

“Mosquitoes have an incredible ability to evolve and adapt, so there may be no permanent fix. However, our current transgenic combination could translate into additional decades of effective use of fungi as an anti-malarial biopesticide,” he said.

If you live in the US, don’t rely on your iPhone’s alarm clock to wake you up on time Monday morning.

Apple has failed to fix a Daylight Saving Time bug in the iPhone’s Alarm app that has already disrupted mornings for many users in Europe and Australia. Even though your iPhone’s internal clock may automatically fall back an hour Sunday morning, a bug in the Alarm app causes it to ignore the Daylight Saving change, which in turn leads certain alarms to go off an hour late.

The bug specifically affects repeating alarms that are scheduled to go off on certain days. Alarms set to repeat every day, or one-time alarms, are reportedly unaffected by the bug.

Apple recommends that users delete existing repeating alarms and rely on one-time alarms until after the Daylight Saving change to Standard Time (2 a.m. EST, Sunday morning). After November 7, you can recreate your repeating alarms. The glitch will be fixed permanently in Apple’s upcoming iPhone operating system 4.2 update, which is slated to land later this month.

European users (and some US users, inexplicably) dealt with the Daylight Saving Time bug last week, which gave Apple only a few days to release a fix in time for the US. Still, Apple doesn’t have much of an excuse — users in Australia and New Zealand first reported the bug several weeks ago.

The company likely doesn’t consider the issue big enough to warrant a software patch of its own, but I’m sure many unhappy iPhone owners who rely on the device as their only alarm clock would disagree.

Via CNN

Tags: bugs, Daylight Savings Time, iOS, iPhone

Companies: Apple