Photo Quiz! Can you tell which one of these women is ovulating and which one is menstruating?

In a study published online last month in the journal Ethology, psychologists Nathan Pipitone at Adams State College and Gordon Gallup at SUNY Albany asked three groups of men to listen to voice recordings of 10 women counting from one to five. Each woman was recorded four times over the course of one full menstrual cycle. (For those who aren’t familiar with the ins and outs of the female reproductive cycle, women are most fertile during ovulation, when their ovaries release an egg, and least fertile during menstruation, when they shed the unfertilized egg and the lining of the uterus.)
After the first group of men listened to all four recordings from each woman, played in random order, they were asked to guess which recordings were made during the women’s periods. The men had a one in four chance of guessing correctly, but they actually did so 35 percent of the time, a significant difference, the researchers say.
In 2008, Pipitone and Gallup showed that men find the voices of ovulating women more attractive than voices recorded during other points in the cycle, so for the second group in the new study, the researchers replaced the recording made closest to ovulation with one from a less fertile day. Even after the potentially telltale contrast was eliminated, the men pinpointed the voice recorded during menstruation 34 percent of the time.
Perhaps the most telling element of the study was the third experiment, in which a new group of men were not told that the research had anything to do with menstrual cycles. Instead they were asked to choose the most “unattractive” voice recording for each woman. They chose the menstrual recording significantly more often than was predicted by chance—again, 34 percent of the time.
In fact, according to the researchers’ calculations, all three groups singled out the voices recorded during menstruation more often than any of the other voices.
So what was it about the women’s voices that gave away their reproductive status? The men in group one who correctly identified the menstrual recordings said they could tell by the mood (bad versus good), quality (harsh versus smooth), pitch (low versus high) and speed (slow versus fast) of the women’s voices. When the second two groups were asked to score the voices based on these characteristics, they reported that menstrual voices sounded lower in mood, quality and pitch. “The men seemed to determine menstrual voices by picking the most unattractive voice,” Pipitone explains.
There’s already evidence that men subconsciously judge where a woman is in her cycle—lap dancers make 80 percent more money in tips when they’re ovulating compared to when they’re menstruating, according to a 2007 paper—but the new study is the first to demonstrate one way men make that determination.
A subconscious (and often conscious) aversion to menstruation makes sense in evolutionary terms, since males wanting to pass on their genes are better off seeking out females closer to ovulation. Over time, the ability to parse a woman’s menstrual cycle could have proliferated, as more perceptive men reproduced more successfully.
Pipitone says the adaptation is an example of the reproductive arms race known as sexually antagonistic coevolution, a phenomenon seen across living species, from humans to brine shrimp. Males show more interest in females when they’re fertile, so it makes sense that human females—who need a lot of help to raise their particularly helpless infants—hide their fertility status. (Female chimps, by contrast, broadcast their fertility with engorged genitalia.) Theoretically, human males retaliated by developing the ability to detect more subtle fertility cues such as those “leaked” by the female voice.
Hormones induce the vocal changes that give women away. “Vocal production is closely tied to our biology,” Pipitone says of men and women. For example, “Cells from the larynx and vagina are very similar and show similar hormone receptors.” The result is that, “The sound of a person’s voice contains a surprising amount of reproductively relevant information,” Gallup says. The obvious example: By speaking on the phone, we can determine a person’s gender and age. But researchers have also shown that voices alone can be used to directly and indirectly predict characteristics like facial appearance, body type, physical strength and even sexual behavior.
I think one of the most interesting results of the study is that across the board, men chose the menstrual voice around a third of the time. It would seem some men are more perceptive to women’s cycles than others. Pipitone and Gallup plan to investigate this question next.

While the purpose of the former is to accumulate excess calories, the latter is used to produce heat. Irisin, named after the Greek goddess Iris, could one day help address obesity and diabetes. However, there is still a long way to go before the hormone is made into an actual drug.

Irisin occurs naturally both in humans and in mice, and its levels surge with physical exercise. Mice have to spend three weeks running on a wheel for the hormone to accumulate in their blood. For humans, the same happens after ten weeks of systematic exercising. A placebo-controlled study showed that boosting the levels of the hormone artificially in mice may induce some of the benefits that would normally be caused by a workout. The cells of the mice injected with irisin needed more oxygen and burned more calories. Obese mice lost several grams within the first ten days from the injection.

The treatment also had a positive effect on the regulation of blood sugar levels, which links the hormone to diabetes prevention. What’s more, Spiegelman’s team plans to investigate the potential of irisin to advance the treatment of diseases such as muscular dystrophy and muscle wasting. "We are hopeful, though we have no evidence, that this hormone may embody some of the other benefits of exercise, perhaps in the neuromuscular system," he says.

This sounds very promising, but there is still a lot to be done before an irisin-based drug comes to a pharmacy near you. First, whether or not irisin will have the same beneficial effects on humans still remains to be seen. Second, making it into an actual drug may turn out to be very challenging, as pointed out by MIT professor Harvay Lodish. Adiponectin, a hormone Lodish discovered back in the early 1990s, also seems to play a role in staving off obesity and diabetes. It is correlated with the body mass index (BMI) and it increases the metabolic rate in mice without raising the food intake. Still, so far all the attempts at converting the full size adiponectin protein into a viable drug have failed.

Professor Spiegelman, however, is optimistic. In fact, he’s optimistic enough to have set up a separate company, called Ember Therapeutics, to conduct brown fat-related research that includes studies on the effects of irisin. Supported by Third Rock Ventures, the company raised US$34 million in the first round of financing. We do hope that all this money and brain power will eventually lead to a treatment for obesity and diabetes. That said, we do recognize that there might be more to it than just swallowing a pill.

That agent, called thrombin, is coated onto sponges that can be easily packed by soldiers and field medics (or civilian medical personnel for that matter) and shaped to fit just about any kind of wound. Those pre-coated sponges are a pretty big improvement over tourniquets and gauze, which are limited in their ability to stop every kind of bleeding. Tourniquets obviously can’t be used on many parts of the body (the neck is a good example), and other glues and chemically treated bandages designed for dressing battlefield wounds come with their own complications and shortcomings.

Thrombin, on the other hand, is already used by the body to stop bleeding. Civilian hospitals also use it already, but it’s in liquid form so sponges must be soaked immediately before they are applied to the wound, making them impractical for the battlefield. MIT’s sponge instead uses a spray-on biological nanoscale coating using alternating layers of thrombin and tannic acid, which results in a film that contains a large amount of functional thrombin with a shelf life that makes it feasible to pack them into the field. Both substances are already FDA approved, the researchers say, which means the sponges could quickly find their way into wider use.

That’s good news for soldiers, and potentially good news for anyone who sustains a trauma far from the emergency room. The MIT lab is now working on a sponge that combines a blood-clotting coating with an antibiotic layer in a single sponge to help fight off infection even as a dressing stops the initial bleeding.

It looks like the Star Trek item that we’re the closest to seeing become a reality, however, is the medical tricorder. This May, the X-PRIZE Foundation proposed a US$10 million Tricorder X-PRIZE, with the intention of encouraging the production of consumer devices that can assess a person’s state of health. The first potential contestant, which already has a tricorder in the works, is a tech start-up by the name of Scanadu.

Founded in January 2011, Scanadu is based out of the NASA Ames Research Center in Mountain View, California, and is headed by CEO and futurist Walter De Brouwer.

Although its inner workings are being kept secret, the Scanadu Tricorder is a small, handheld device, that would be used in conjunction with the processing power and screen of a smartphone. In a non-contact, non-invasive fashion, it would be able to measure vital statistics such as blood pressure, pulmonary function, and body temperature. An onboard hyper-spectral camera and microfluidic lab-on-a-chip would also be able to analyze rashes and infections, and process blood and saliva samples, respectively.

Based on these and other measurements, it could then offer a diagnosis, and advise its user on what course of action should be taken. If a doctor needed to be involved, the patient data on the tricorder could be instantly transferred to them. If it turned out to be something that could be treated at home, then an unnecessary trip to the emergency room or doctor’s office would be avoided.

The first generation of the tricorder will be aimed at parents, for use on their young children. Although it’s hard to know just how far along the device is in its development, Scanadu did recently announce that it had received US$2 million in funding from a group of private investors – that’s certainly going to help.

Other products have already made steps in the direction of smartphone-based tricorders. Melapp and the Handyscope utilize a phone’s camera to assess suspicious skin markings, the iHealth system helps users manage their weight and blood pressure, while iBGStar allows diabetics to measure their blood glucose levels.

PlateMate is a crowd-sourced dieting system, in which an online community determines the caloric value of users’ meals

Although taking such an approach to nutrition might sound kind of iffy, calorie estimates generated by the crowd-sourced system are apparently just as accurate as those provided by trained nutritionists, and more accurate than self-kept logs.

PlateMate was first developed by Jon Noronha and Eric Hysen, when they were undergrads in Harvard University’s School of Engineering and Applied Sciences.

Users start by taking a photo of their meal, then submitting it to the crowd. That crowd is coordinated using Amazon Mechanical Turk, a collaborative system that was first developed to help improve Amazon product listings. Individual Turkers, as they’re called, look over the submitted photos and try to determine which foods are present in each one, and in what approximate quantities. The total caloric value of the meal is then automatically calculated, the system averages out the totals generated by the various Turkers, and the user is provided with their answer.

Each Turker receives a nominal payment for every task they accomplish.

Presumably, PlateMate users don’t sit around with the food still on their plate, waiting to see the results before tucking in. The crowd feedback for one meal choice, however, could guide them in choosing types and amounts of foods in subsequent meals.

There were some hiccups (no pun intended) in setting up the system. Some Turkers, for instance, misidentified foods submitted by users from other cultures. Other Turkers took the lazy approach – from an on-screen list of types of food, they simply selected the first term that had some relevance to a food they had identified, instead of searching through the list for a more specific term. These problems were addressed by breaking the process down into clearly defined tasks, posting warnings about common errors, being more selective when choosing Turkers, and applying algorithms that chose the most-likely-to-be-accurate food identification from a number that were selected for one item.

Down the road, user submissions may also be pared with locational data, so Turkers will know the geographical context of what they’re looking at.

"A lot of prior crowdsourcing research has been about making crowds do things that we wish computers could do, like shorten an 800-word essay to 500 words and have it still make sense," said Noronha. "What makes the nutrition application so interesting as a problem in crowdsourcing is that computers are so very far away from doing it on their own – because food is such a human thing."

The cerebellum is located on the underside of the brain, beside the brain stem. It plays a large part in motor control, particularly as it applies to the coordination and timing of movements. Its fairly simple neuronal structure made it less challenging to replicate, as compared to other more complex regions of the brain.

The team, led by Professor of Psychobiology Matti Mintz, started by analyzing the sensory input signals that came into a rat’s biological cerebellum from its brain stem, and the response signals that it put out in return. They were then able to replicate this signal-processing/transmitting function on a chip, which could be mounted outside the rat’s skull and wired into its brain.

They then anesthetized the rat, disabled its own cerebellum, and mounted the chip on its head. Next, they tried to teach the still-anesthetized rat a conditioned motor reflex – they subjected the rat’s eye to a puff of air accompanied by an audible tone, causing it to blink, with the idea that the rat would learn to blink its eye even when the tone was produced with no accompanying puff. While it could not learn this response when the chip was at first not connected to its brain, it was able to do so once the chip was wired in.

The chip was facilitating the same sort of response that the cerebellum would ordinarily handle.

Now, Mintz and his Tel Aviv team hope to replicate larger areas of the cerebellum, which would allow conscious test animals to learn whole sequences of response movements. It should prove challenging, as artefacts caused by the movements themselves can degrade the signal quality, although better software and improved implantation techniques could make up for that degradation.

Ultimately, the descendants of such chips could be used to restore or at least improve brain functions in stroke victims, or other people with brain damage. Mintz’s collaborator, Robert Prueckl of Austria’s Guger Technologies, believes that even brain parts such as the hippocampus or visual cortex should have artificial counterparts within several decades.

More and more we’re hearing about clothing made from smart fabrics being used in the field of medicine, to monitor patients wearing such garments.

The prototype shirt is washable and incorporates electrodes that detect bioelectric power, such as that created by the beating of the heart – an electrocardiogram can be obtained using these electrodes.

It also features a removable device that includes a thermometer and accelerometer. These are used to measure the patient’s body temperature, along with their position (such as whether they’re reclining or standing, for instance) and their level of physical activity.

Another device, which the researchers plan on building into the shirt, receives signals from a network of transmitters located throughout the hospital. It proceeds to wirelessly send information about those signals to a central information management system, which applies an algorithm to establish the wearer’s location within the building. It has a two-meter (6.6-foot) margin of error.

Down the road, the UC3M team believe that the shirt could be used not only within hospitals, but also to remotely monitor patients in their homes. Alarms built into the T-shirt could notify doctors or other hospital personnel when the patient’s heart rate exceeds a given limit, or when their body temperature drops significantly below the normal 37C (98.6F).

Similar projects have included Philips’ patient-monitoring bras, briefs and waist belts, and BIOTEX‘s clothing that analyzes bodily fluids.

A lopsided self-propelled micromotor could drive itself through blood vessels, making repairs or delivering drugs along the route, according to researchers at Penn State. The small particles leach out a trail of material, like a microspider spinning a thread.

The motors turn on, as it were, when one side of a Janus microsphere grows a suite of molecules on one side. Eventually, the lopsided sphere creates an osmotic gradient. As fluid flows toward the area with fewer particles, the whole sphere moves.

Janus microspheres have two distinct hemispheres made of different substances. In this case, one half is gold and the other is silicon dioxide. Researchers led by Ayusman Sen at Penn State attached a molecule called a Grubbs catalyst, which induces polymerization, to the silica side. Then they added a monomer, which the catalyst strings into long chains. The monomer strings gather on the SiO2 side, which creates a mini current that sends the whole sphere moving the opposite direction.

To prove it can deliver substances, the scientists filled a gel substance with the monomer, which was slowly leached out. The micromotors moved toward the gel stream, like a single-celled organism following a trail of nutrient breadcrumbs.

This could be a handy, electricity-free way to send tiny devices into the bloodstream to do various tasks. The microspider motors could drive nanorobots that destroy tumor cells, or they could target drugs to specific organs more quickly, for instance.

Micromachines in the Bloodstream: The micromotors use a catalyst that binds asymmetrically to a Janus (two-sided) microsphere.

Writing in the journal Nature this week, Martin Blaser of NYU’s Langone Medical Center makes the case that antibiotics aren’t just leading to highly resistant superbugs, but that they are permanently altering our bacterial microbiomes, and not for the better.

Our microbiomes are the collection of bacterial microbes that we carry around with us all the time, those symbiotic little bugs that live on our skin and in our esophagi and–very importantly–in our guts. And while we’ve long known that a cycle of antibiotics prescribed to kill off an infection can also kill off some of our most important beneficial microorganisms, the general line of thinking is that once the cycle of antibiotics ends our microbiomes correct themselves and the natural order of things returns.

Blaser presents arguments otherwise in an editorial that suggests that our gut bacteria is permanently affected by a cycle of antibiotics, and that the impact is so profound that it might be time to seriously consider not giving antibiotics to anyone other than very young children and pregnant women. Quoted by Maryn McKenna in Wired:

Early evidence from my lab and others hints that, sometimes, our friendly flora never fully recover. These long-term changes to the beneficial bacteria within people’s bodies may even increase our susceptibility to infections and disease. Overuse of antibiotics could be fueling the dramatic increase in conditions such as obesity, type 1 diabetes, inflammatory bowel disease, allergies and asthma, which have more than doubled in many populations.

He then goes on to present some disconcerting correlations between the absence of certain bacteria and the rise in incidences of things like allergy, asthma, and weight gain. He points to evidence that children are getting too many doses of antibiotics before adulthood and that their microbiomes are never the same for it–specifically that the damage to our gut bacteria populations is permanent from that point forward.

Which leads to an eventual conclusion that when our children are sick we shouldn’t give them what we know will make them better. And that’s a tough pill to swallow.

Virus Therapy In the left set, rhinovirus (the common cold virus) kills untreated human cells (lower left), whereas DRACO has no toxicity in uninfected cells (upper right) and cures an infected cell population (lower right). Similarly, in the right set, dengue hemorrhagic fever virus kills untreated monkey cells (lower left), whereas DRACO has no toxicity in uninfected cells (upper right) and cures an infected cell population (lower right).

These include rhinoviruses that cause the common cold, H1N1 influenza, a stomach virus, a polio virus, dengue fever and several other types of hemorrhagic fever.

While there are a number drugs that are effective against specific viruses, such as the protease inhibitors used to control HIV infection, they are relatively rare and susceptible to viral resistance. In a development that could change the way viral infections are treated, the MIT researchers have designed a drug that can identify cells that have been infected not just by a specific virus, but by any virus, then kill those cells to terminate the infection.

When viruses infect a cell, they hijack its cellular machinery to create more copies of the virus, which then infect other cells, and so on. During this replication process, the viruses create long strings of double-stranded RNA (dsRNA), which isn’t found in human or other animal cells. While human cells have proteins that latch onto dsRNA, which sets off a cascade of reactions that prevents the virus from replicating, many viruses are able to circumvent this by blocking one of the steps further down the cascade.

To get around this problem, Todd Rider, a senior staff scientist in Lincoln Laboratory’s Chemical, Biological, and Nanoscale Technologies Group, had the idea of combining a dsRNA-binding protein with another protein that causes cells to undergo programmed cell suicide – a process called apoptosis.

The therapeutic agents devised by Rider are dubbed DRACOs (Double-stranded RNA Activated Caspase Oligomerizers). When one end of the DRACO binds to dsRNA, it signals the other end to initiate cell suicide. However, if it enters a cell and finds no dsRNA present, it leaves the cell unharmed. Because each DRACO also includes a "delivery tag," taken from naturally occurring proteins, it is able to cross cell membranes and enter any human or animal cell.

In addition to testing DRACO in human and animal cells cultured in the lab, the MIT team has also tested it in mice infected with the H1N1 influenza virus. Treated mice were completely cured of the infection and DRACO itself was shown to be not toxic to the mice. The team is now testing DRACO against more viruses in mice and reports promising results. Rider says he hopes to license the technology for trials in larger animals with his sights on eventual human clinical trials.