G-300: The first French Getaway Special microgravity measurements of fluid thermal conductivity

Thermal conductivity measurements on liquids are difficult to perform on Earth because of thermal motions due to convection. In microgravity, the convection due to buoyancy is evanescent, and a strong reduction of Rayleigh and Nusselt numbers can be expected. Three low viscosity liquids are selected to carry out the measurements; distilled water (standard) and two silicone oils. A modified hot plate method with a simplified guard ring is used; the reduction of convective motions permitted the use in the experimental cells of larger interplate distances and/or temperature differences than in Earth measurements, improving the accuracy. Comparisons between Earth and orbit results may help to understand the convection occurrence in the cells. Thermal, vibrational, and EMI tests have proved that the design satisfies the NASA requirements

Developing global climate anomalies suggest potential disease risks for 2006 – 2007

BACKGROUND: El Niño/Southern Oscillation (ENSO) related climate anomalies have been shown to have an impact on infectious disease outbreaks. The Climate Prediction Center of the National Oceanic and Atmospheric Administration (NOAA/CPC) has recently issued an unscheduled El Niño advisory, indicating that warmer than normal sea surface temperatures across the equatorial eastern Pacific may have pronounced impacts on global tropical precipitation patterns extending into the northern hemisphere particularly over North America. Building evidence of the links between ENSO driven climate anomalies and infectious diseases, particularly those transmitted by insects, can allow us to provide improved long range forecasts of an epidemic or epizootic. We describe developing climate anomalies that suggest potential disease risks using satellite generated data. RESULTS: Sea surface temperatures (SSTs) in the equatorial east Pacific ocean have anomalously increased significantly during July – October 2006 indicating the typical development of El Niño conditions. The persistence of these conditions will lead to extremes in global-scale climate anomalies as has been observed during similar conditions in the past. Positive Outgoing Longwave Radiation (OLR) anomalies, indicative of severe drought conditions, have been observed across all of Indonesia, Malaysia and most of the Philippines, which are usually the first areas to experience ENSO-related impacts. This dryness can be expected to continue, on average, for the remainder of 2006 continuing into the early part of 2007. During the period November 2006 – January 2007 climate forecasts indicate that there is a high probability for above normal rainfall in the central and eastern equatorial Pacific Islands, the Korean Peninsula, the U.S. Gulf Coast and Florida, northern South America and equatorial east Africa. Taking into consideration current observations and climate forecast information, indications are that the following regions are at increased risk for disease outbreaks: Indonesia, Malaysia, Thailand and most of the southeast Asia Islands for increased dengue fever transmission and increased respiratory illness; Coastal Peru, Ecuador, Venezuela, and Colombia for increased risk of malaria; Bangladesh and coastal India for elevated risk of cholera; East Africa for increased risk of a Rift Valley fever outbreak and elevated malaria; southwest USA for increased risk for hantavirus pulmonary syndrome and plague; southern California for increased West Nile virus transmission; and northeast Brazil for increased dengue fever and respiratory illness. CONCLUSION: The current development of El Niño conditions has significant implications for global public health. Extremes in climate events with above normal rainfall and flooding in some regions and extended drought periods in other regions will occur. Forecasting disease is critical for timely and efficient planning of operational control programs. In this paper we describe developing global climate anomalies that suggest potential disease risks that will give decision makers additional tools to make rational judgments concerning implementation of disease prevention and mitigation strategies

Misconceptions about Mirror-Induced Motor Cortex Activation

Observation of self-produced hand movements through a mirror, creating an illusion of the opposite hand moving, was recently reported to induce ipsilateral motor cortex activation, that is, motor cortex activation for the hand in rest. The reported work goes far beyond earlier work on motor cortex activation induced by action observation, by implying a complete reversal of contralateral and ipsilateral motor cortex activation under mirror view conditions. Such a reversal would represent an unprecedented degree of neural plasticity. We considered such a reversal physiologically implausible and conducted a study with an improved design. The results refute the reversal of contralateral and ipsilateral motor cortex activation under mirrored viewing conditions as methodologically unsound. The investigation confirmed, however, more subtle expressions of motor cortical activity induced by self-produced movements observed through a mirror

Hearing-Related Quality of Life in 75 Patients With a Percutaneous Bone Conduction Device

Objective: To evaluate long-term hearing-related quality of life (HRQoL) and device use in bone conduction (BCD) users. Furthermore, to assess differences between indications and changes in HRQoL over time. Study design: Prospective questionnaire survey. Setting: Tertiary referral center. Patients: Seventy-five patients with a percutaneous BCD. Main outcome measures: Glasgow Benefit Inventory (GBI) at 3 and 12 months postoperatively, Glasgow Health Status Inventory (GHSI) preoperatively, and 6 and 36 months postoperatively, device use at 6, 12, and 36 months. Changes over time were assessed and outcomes were compared between indications. Results: After implantation, 97% of all patients reported a positive benefit on the GBI total. The GHSI total had improved with median 15 points (Interquartile range [IQR] 12). At 36 months, median device use was 15 hours/day (IQR 10) and one nonuser was reported. Patients with bilateral hearing loss (BHL) showed greater improvement on the GHSI total (median 18 vs 14, p &lt; 0.0001) and used their devices more frequently (median 16 vs 8 h/day, p &lt; 0.0001) than patients with unilateral HL (UHL). Postoperative GHSI and GBI scores were consistent over time, in the entire patient population and for every indication. Between 6 and 36 months, device use was stable over time, except for patients with single-sided deafness (SSD; median -6.4 h/day, p = 0.009). Conclusion: The BCD improves HRQoL in patients with BHL, in patients with unilateral conductive/mixed hearing loss and in patients with SSD. Patients with BHL experienced a greater improvement in hearing status compared to patients with UHL. Although use decreased over time in SSD patients, device use was high for every indication.</p

International Health Regulations—What Gets Measured Gets Done

Focus on goals and metrics for 4 core capacities illustrates 1 approach to implementing IHR

A 1-acetamido derivative of 6-epi-valienamine: an inhibitor of a diverse group of β-N-acetylglucosaminidases

The synthesis of an analogue of 6-epi-valienamine bearing an acetamido group and its characterisation as an inhibitor of β-N-acetylglucosaminidases are described. The compound is a good inhibitor of both human O-GlcNAcase and human β-hexosaminidase, as well as two bacterial β-N-acetylglucosaminidases. A 3-D structure of the complex of Bacteroides thetaiotaomicron BtGH84 with the inhibitor shows the unsaturated ring is surprisingly distorted away from its favoured solution phase conformation and reveals potential for improved inhibitor potency

From coordination to stochastic models of QoS

Reo is a channel-based coordination model whose operational semantics is given by Constraint Automata (CA). Quantitative Constraint Automat

Elastic properties of grafted microtubules

We use single-particle tracking to study the elastic properties of single microtubules grafted to a substrate. Thermal fluctuations of the free microtubule's end are recorded, in order to measure position distribution functions from which we calculate the persistence length of microtubules with contour lengths between 2.6 and 48 micrometers. We find the persistence length to vary by more than a factor of 20 over the total range of contour lengths. Our results support the hypothesis that shearing between protofilaments contributes significantly to the mechanics of microtubules.Comment: 9 pages, 3 figure

Shigella Effector IpaB-Induced Cholesterol Relocation Disrupts the Golgi Complex and Recycling Network to Inhibit Host Cell Secretion

Shigella infection causes destruction of the human colonic epithelial barrier. The Golgi network and recycling endosomes are essential for maintaining epithelial barrier function. Here we show that Shigella epithelial invasion induces fragmentation of the Golgi complex with consequent inhibition of both secretion and retrograde transport in the infected host cell. Shigella induces tubulation of the Rab11-positive compartment, thereby affecting cell surface receptor recycling. The molecular process underlying the observed damage to the Golgi complex and receptor recycling is a massive redistribution of plasma membrane cholesterol to the sites of Shigella entry. IpaB, a virulence factor of Shigella that is known to bind cholesterol, is necessary and sufficient to induce Golgi fragmentation and reorganization of the recycling compartment. Shigella infection-induced Golgi disorganization was also observed in vivo, suggesting that this mechanism affecting the sorting of cell surface molecules likely contributes to host epithelial barrier disruption associated with Shigella pathogenesis

Differential Susceptibility to Hypertension Is Due to Selection during the Out-of-Africa Expansion

Hypertension is a leading cause of stroke, heart disease, and kidney failure. The genetic basis of blood pressure variation is largely unknown but is likely to involve genes that influence renal salt handling and arterial vessel tone. Here we argue that susceptibility to hypertension is ancestral and that differential susceptibility to hypertension is due to differential exposure to selection pressures during the out-of-Africa expansion. The most important selection pressure was climate, which produced a latitudinal cline in heat adaptation and, therefore, hypertension susceptibility. Consistent with this hypothesis, we show that ecological variables, such as latitude, temperature, and rainfall, explain worldwide variation in heat adaptation as defined by seven functional alleles in five genes involved in blood pressure regulation. The latitudinal cline in heat adaptation is consistent worldwide and is largely unmatched by latitudinal clines in short tandem repeat markers, control single nucleotide polymorphisms, or non-functional single nucleotide polymorphisms within the five genes. In addition, we show that latitude and one of these alleles, GNB3 (G protein β3 subunit) 825T, account for a major portion of worldwide variation in blood pressure. These results suggest that the current epidemic of hypertension is due to exposures of the modern period interacting with ancestral susceptibility. Modern populations differ in susceptibility to these new exposures, however, such that those from hot environments are more susceptible to hypertension than populations from cold environments. This differential susceptibility is likely due to our history of adaptation to climate