Surprise: Lost stem cells naturally replaced by non-stem cells, fly research suggests

Johns Hopkins researchers have discovered an unexpected phenomenon in the organs that produce sperm in fruit flies: When a certain kind of stem cell is killed off experimentally, another group of non-stem cells can come out of retirement to replace them.

Refining the language for chromosomes

Boston, MA – When talking about genetic abnormalities at the DNA level that occur when chromosomes swap, delete or add parts, there is an evolving communication gap both in the science and medical worlds, leading to inconsistencies in clinical and research reports.

Gene variant raises risk for aortic tear and rupture

New Haven, Conn. — Researchers from Yale School of Medicine and Celera Diagnostics have confirmed the significance of a genetic variant that substantially increases the risk of a frequently fatal thoracic aortic dissection or full rupture. The study appears online in PLOS ONE.

First structural insights into how plant immune receptors interact

Researchers at The Sainsbury Laboratory (TSL), Norwich, collaborating with structural biologist Bostjan Kobe in Brisbane, have made a major advance in understanding plant disease resistance.

Weight gain in children occurs after tonsil removal, not linked to obesity

Weight gain in children after they have their tonsils removed (adenotonsillectomy) occurs primarily in children who are smaller and younger at the time of the surgery, and weight gain was not linked with increased rates of obesity.

The story of animal domestication retold

It is from Darwin that we inherit the ideas that domestication involved isolation of captive animals from wild species and total human control over breeding and animal care.

Genetic study tackles mystery of slow plant domestications

It seems so straightforward and yet the more scientists learn, the more complex the story becomes. Recently, geneticists and archeologists working on domestication compared notes and up popped a question of timing. Did domesticating a plant typically take a few hundred or many thousands of years?

Dual role: Key cell division proteins also power up mitochondria

(SACRAMENTO, Calif.) — An international team led by researchers at UC Davis has shown that the cyclin B1/Cdk1 protein complex, which plays a key role in cell division, also boosts the mitochondrial activity to power that process. This is the first time the complex has been shown to perform both jobs. This newfound ability could make cyclin B1/Cdk1 an excellent target to control cellular energy production, potentially advancing cancer care and regenerative medicine. The research was published online today in the journal Developmental Cell.

Thinnest feasible membrane produced

Researchers have produced a stable porous membrane that is thinner than a nanometre. This is a 100,000 times thinner than the diameter of a human hair. The membrane consists of two layers of the much exalted "super material" graphene, a two-dimensional film made of carbon atoms, on which the team of researchers, led by Professor Hyung Gyu Park at the Department of Mechanical and Process Engineering at ETH Zurich, etched tiny pores of a precisely defined size.

ASU researchers urge alternative identification methods for threatened species

Researchers at Arizona State University and Plymouth University in the United Kingdom want to change the way biologists think about the "gold standard" of collecting a "voucher" specimen for species identification. They suggest that current specimen collection practices may actually pose a risk to vulnerable animal populations already on the brink of extinction.

Newlyweds, be careful what you wish for

A statistical analysis of the gift "fulfillments" at several hundred online wedding gift registries suggests that wedding guests are caught between a rock and a hard place when it comes to buying an appropriate gift for the happy couple. The details reported in the International Journal of Electronic Marketing and Retailing suggest that most people hope to garner social benefits of buying an expensive gift that somehow enhances their relationship with the newlyweds while at the same time they wish to limit monetary cost and save money.

More effective kidney stone treatment, from the macroscopic to the nanoscale

Kidney stones represent a major medical problem in the western and developing world. If left untreated, apart from being particularly painful, they can lead to renal failure and other complications. In many patients treated successfully, stone recurrence is also amajor problem. Clearly a more effective pathological approach to diagnosis and treatment needs to be identified to ensure successful eradication of stones.

Biomedical applications of shape-memory polymers: How practically useful are they?

The shape-memory effect, as exhibited by metal alloys such as nitinol as well as many polymers, is the ability of a material to change its dimension in a predefined way in response to an external stimulus. For the many medical implants that can be deployed in the body using minimally invasive means, the implant dimension should be small during deployment and must regain a larger shape after deployment. Examples of such devices include stents, heart valves and septal defect occluders. As the range of available materials expands, so will the range of applications. Although the filed has been long dominated by one single material, nitinol (an alloy of nickel and titanium), polymers are challenging this dominance because they offer more functionality than simple ease of deployment.

Chiral breathing: Electrically controlled polymer changes its optical properties

An international team of chemists from Italy, Germany, and Poland developed a polymer with unique optical and electric properties. Components of this polymer change their spatial configuration depending on the electric potential applied. In turn, the polarisation of transmitted light is affected. The material can be used, for instance, in polarisation filters and window glasses with continuously adjustable transparency. Due to its mechanical properties, the polymer is also perfectly suitable for fabrication of chemical sensors for selective detection and determination of optically active (chiral) forms of an analyte.

Testing protocols in Internet of Things by a formal passive technique

Extensible Messaging and Presence Protocol (XMPP) has gained more attention as a communication protocol in Internet of Things (IoT), which is a standardized protocol by Internet Engineering Task Force (IETF) and well established in the Internet. XMPP is available for commonly used programming languages and device platforms. Several studies have investigated the potentialities of applying XMPP in IoT. With the tendency that XMPP is more and more widely used in many aspects of IoT, the problem of formally testing this protocol in a wireless environment is coming out in the wash.

In sex-reversed cave insects, females have the penises

"Although sex-role reversal has been identified in several different animals, Neotrogla is the only example in which the intromittent organ is also reversed," says Kazunori Yoshizawa from Hokkaido University in Japan.

Methane climate change risk suggested by proof of redox cycling of humic substances

The recent Yokahama IPCC meeting painted a stark warning on the possible effects of gases such as methane – which has a greenhouse effect 32 times that of carbon dioxide. Now a team of Swiss-German researchers have shown that humic substances act as fully regenerable electron acceptors which helps explain why large amount of methane are held in wetlands instead of being released to the atmosphere. However, there are worries that if this system is disrupted it may enter into a vicious cycle to release large amounts of methane back into the atmosphere.

Researcher looks at public perceptions around newborn testing

Most newborns in North America have a "heel prick test" in their first day or two of life in which a tiny amount of blood is taken from their heels and tested for about five to 54 conditions, depending on the state or province. Some conditions commonly tested for include cystic fibrosis, the enzyme deficiency phenylketonuria or PKU, and hypothyroidism, a thyroid hormone deficiency.

Wireless power transfer achieved at 5-meter distance

Chun T. Rim, a professor of Nuclear & Quantum Engineering at KAIST, and his team showcased, on April 16, 2014 at the KAIST campus, Daejeon, Republic of Korea, a great improvement in the distance that electric power can travel wirelessly. They developed the "Dipole Coil Resonant System (DCRS)" for an extended range of inductive power transfer, up to 5 meters between transmitter and receiver coils.

Animal study provides first evidence that gel can prevent multiple virus transmission in vagina/rectum

NEW YORK (17 April 2014)— Population Council scientists and their partners have found that their proprietary microbicide gel is safe, stable, and can prevent the transmission of multiple sexually transmitted infections (STIs) in both the vagina and rectum in animals: HIV, herpes simplex virus 2 (HSV-2), and human papillomavirus (HPV). The USAID-funded study also provides the first data that the gel is effective against multiple strains of HIV, and has a window of efficacy in the vagina against all three viruses of at least eight hours prior to exposure. A Phase 1 safety trial of the gel is set to begin enrollment in May 2014.