ISS Astronauts Parmitano and Cassidy EVA: Orbital repair men

Astronauts Luca Parmitano and Chris Cassidy switched their spacesuits to battery power and began their spacewalk outside the International Space Station.

The sortie was planned for six and half hours, but the astronauts proceeded faster than planned and had time for extra 'get-ahead' tasks, routing cables and staging equipment to help future spacewalkers.

The final duration of Tuesday's extravehicular activity was 6 hours and 7 minutes.

The primary goals were to replace a Ku-band communications transceiver, retrieve two science experiments that exposed material samples to space, install cables for Russia's coming Nauka laboratory module, and carry out routine maintenance.

An artist impression of Nauka in situ on the ISS.

Nauka will replace the Pirs module currently attached to the Station.

The highlight of the spacewalk for Luca was surely riding on the platform at the end of the Station's Canadarm2 robot arm - this moment is shown in the image.

Operated by Karen Nyberg inside the Station, the arm moved Luca to the port side of the Station's long central truss to remove a failed camera that will be returned to Earth for analysis.

Finally, Luca installed a multilayer insulation cover to protect the docking interface of the Pressurized Mating Adapter-2 on the Harmony module.

Luca and Chris will venture out to space again next week to continue work started during this spacewalk.

Testosterone reduces the empathetic responses in Women

Testosterone - Lauded by some and viewed with suspicion by others, few people have a completely neutral view of the hormone that separates boys from girls.

According to the extreme male brain theory of autism, the organising effects of testosterone on the brain in utero, and its ongoing shaping of social behaviors throughout life, explains why men exhibit more aggressive, risk-taking behaviour than women do.

It may also account for the social intelligence deficits of people with autism and the skewed gender ratio of the disorder.

A new study shows that even a little bit of testosterone administered under the tongue can cause a woman to show less empathy — to behave, in other words, more like a man.

This is especially true, researchers say, when a woman has been exposed to higher-than-average levels of testosterone as a fetus.

The 2D:4D Finger Test
One increasingly accepted marker of fetal androgen exposure is the 2D:4D ratio, comparing the length of the index finger to that of the ring finger on the right hand. In women, the ring finger is typically longer than the index finger, whereas in men, or in individuals with high fetal testosterone exposure, the two fingers are of nearly identical length.

Exposure to lower testosterone levels in utero, as inferred by a higher 2D:4D ratio, may protect men from prostate cancer. Researchers have also reported lower 2D:4D ratios in children with autism and in their parents and siblings.

In the study, researchers administered a single 0.5 mg dose of testosterone to 16 young women between 20 and 25 years of age in one session, and a single dose of placebo in a second session 48 hours later. The women experienced a ten-fold increase in blood testosterone levels 15 minutes after intake, with the levels returning to baseline in about an hour and a half.

During that time, the participants took a test of cognitive empathy called Reading the Mind in the Eyes, which asks them to infer the emotions expressed in a photograph of a pair of eyes. Interestingly, 75 percent of the women in the study achieved lower scores on the test after testosterone than after placebo.

When the researchers compared the women's 2D:4D ratios, as computed from scans of their right hands, they found something even more interesting: the women with the lowest 2D:4D ratios (highest fetal testosterone exposure) showed the most significant decrease in empathy as measured by the test.

This may not be not a slam-dunk for the extreme male brain theory, but the results jibe with other studies that have found a continuum of social cognition abilities.

Men and women respond to stress in different ways

Men and women respond differently to stress ScienceBlog.com

Defensiveness is a trait characterised by avoidance, denial or repression of information perceived as threatening. In women, a strong defensive reaction to judgment from others or a threat to self-esteem will result in high blood pressure and heart rate. Contrarily, older men with low defensive reactions have a higher cardiovascular rates.

A study was conducted on 81 healthy working men and 118 women. According to Dr. Jean-Claude Tardif a Université de Montréal professor and Montreal Heart Institute researcher, the physiological response to stress in women and older men is linked to this desire of maintaining self-esteem and securing social bonds.

"The sense of belonging is a basic human need," says D'Antono. "Our findings suggest that socialising is innate and that belonging to a group contributed to the survival of our ancestors. Today, it is possible that most people view social exclusion as a threat to their existence. A strong defensive reaction is useful to maintain one's self-esteem faced with this potential threat."

As part of the experiment, participants completed four tasks of varying stress levels.

• The first task involved reading a neutral text on Antarctica's geography before a person of the same sex.
• The second and third tasks involved role-playing in which participants followed a script where they were sometimes agreeable and sometimes aggressive.
• The final task involved a non-scripted debate on abortion.

Heart rate and blood pressure were measured during each of these tasks as was the level of cortisol in saliva. Results showed that women and older men had elevated cardiovascular, autonomic and endocrine responses to stress, all potentially damaging to their health.

However. the research team cautions that more studies are needed to evaluate the long-term effects of defensiveness and its association to stress response patterns in disease development.

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