Can cirrus clouds produce glories?

A vague glory display was photographed over central Utah from an airplane beginning its descent through a cirrus cloud layer with an estimated cloud top temperature of -45 and -55 degrees C. Photographic analysis reveals a single reddish-brown ring of 2.5-3.0 degrees radius around the antisolar point, although a second ring appeared visually to have been present over the brief observation period. Mie and approximate nonspherical theory scattering simulations predict a population of particles with modal diameters between 9 and 15 mum. Although it is concluded that multiple-ringed glories can be accounted for only through the backscattering of light from particles that are strictly spherical in shape, the poor glory colorization in this case could imply the presence of slightly aspherical ice particles. The location of this display over mountainous terrain suggests that it was generated by an orographic wave cloud, which we speculate produced numerous frozen cloud droplets that only gradually took on crystalline characteristics during growth.     

Identification of anovulation and transient luteal function using a urinary pregnanediol-3-glucuronide ratio algorithm

The sensitivity and specificity of a urinary pregnanediol-3-glucuronide (PdG) ratio algorithm to identify anovulatory cycles was studied prospectively in two independent populations of women. Urinary hormone data from the first group was used to develop the algorithm, and data from the second group was used for its validation. PdG ratios were calculated by a cycles method in which daily PdG concentrations indexed by creatinine (CR) from cycle day 11 onward were divided by a baseline PdG (average PdG/Cr concentration for cycle days 6-10). In the interval method, daily PdG/CR concentrations from day 1 onward were divided by baseline PdG (lowest 5-day average of PdG/CR values throughout the collection period). Evaluation of the first study population (n = 6) resulted in cycles with PdG ratios > or = 3 for > or = 3 consecutive days being classified as ovulatory; otherwise they were anovulatory. The sensitivity and specificity of the PdG ratio algorithm to identify anovulatory cycles in the second population were 75% and 89.5%, respectively, for all cycles (n = 88); 50% and 88.3% for first cycles (n = 40) using the cycles method; 75% and 92.2%, respectively, for all cycles (n = 89); and 50% and 94.1% for first cycles (n = 40) using the interval method. The "gold standard" for anovulation was weekly serum samples < or = 2 ng/ml progesterone. The sensitivity values for all cycles and for the first cycle using both methods were underestimated because of apparent misclassification of cycles using serum progesterone due to infrequent blood collection. Blood collection more than once a week would have greatly improved the sensitivity and modestly improved the specificity of the algorithm. The PdG ratio algorithm provides an efficient approach for screening urine samples collected in epidemiologic studies of reproductive health in women.     

Full-body interface pressure testing as a method for performance evaluation of clinical support surfaces

A method for evaluating the performance of clinical support surfaces is required by designers in their efforts to produce better clinical support surfaces that will reduce the incidence of pressure ulcers. In this study, a Pressure Index (P_index) is defined which is derived from an analytical equation used to evaluate the average interface pressure, the peak pressure, the magnitude of the peak pressure, and the number of peak pressures on the entire body. The type of subjects needed to represent a population of users as well as the head of bed elevations necessary to simulate clinical applications were integrated with the P_index to create a single-value mean pressure index which can be used to evaluate any type of surface. To determine the accuracy and repeatability of the mean pressure index, three surfaces (a standard hospital innerspring, a replacement foam mattress, and a low-airloss surface) were tested and evaluated using this method. The low airloss performed the best and the standard innerspring clearly performed the worst (p < 0.0001). The method appeared to accurately and reproducibly predict the relative performance of the three surfaces in reducing pressure.     

Quorum sensing in Escherichia coli, Salmonella typhimurium, and Vibrio harveyi: a new family of genes responsible for autoinducer production

In bacteria, the regulation of gene expression in response to changes in cell density is called quorum sensing. Quorum-sensing bacteria produce, release, and respond to hormone-like molecules (autoinducers) that accumulate in the external environment as the cell population grows. In the marine bacterium Vibrio harveyi two parallel quorum-sensing systems exist, and each is composed of a sensor-autoinducer pair. V. harveyi reporter strains capable of detecting only autoinducer 1 (AI-1) or autoinducer 2 (AI-2) have been constructed and used to show that many species of bacteria, including Escherichia coli MG1655, E. coli O157:H7, Salmonella typhimurium 14028, and S. typhimurium LT2 produce autoinducers similar or identical to the V. harveyi system 2 autoinducer AI-2. However, the domesticated laboratory strain E. coli DH5alpha does not produce this signal molecule. Here we report the identification and analysis of the gene responsible for AI-2 production in V. harveyi, S. typhimurium, and E. coli. The genes, which we have named luxSV.h., luxSS.t., and luxSE.c. respectively, are highly homologous to one another but not to any other identified gene. E. coli DH5alpha can be complemented to AI-2 production by the introduction of the luxS gene from V. harveyi or E. coli O157:H7. Analysis of the E. coli DH5alpha luxSE.c. gene shows that it contains a frameshift mutation resulting in premature truncation of the LuxSE.c. protein. Our results indicate that the luxS genes define a new family of autoinducer-production genes.     

Inducing affect about self or other: Effects on generosity in children.

85 7–12 yr olds were asked to discuss happy, sad, or affectively neutral incidents that had been experienced either by themselves or by another child. Following the inducement of affect, the Ss were given the opportunity to share their experimental earnings with some less fortunate children. As predicted, a significant interaction of the discussion topic (self/other) and affect was found. Ss relating sad experiences encountered by another individual shared significantly more than those describing sad incidents that they had experienced. Although older Ss were more generous than the younger Ss in sharing their experimental earnings, age did not interact with the other experimental variables. (11 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

On‐line learning: A quality experience

The paper outlines the strategy being developed for the growth of electronic books within the UK academic community and provides a broad analysis of the e‐book industry and critical factors. The role of the JISC E‐Books Working Group is described and an overview given of its programme of activities.     

Preventing problems of professional competence in the face of life-threatening illness.

When a psychologist is diagnosed with a serious medical condition and faces the prospect of an arduous treatment regimen and perhaps a bleak prognosis, it may be difficult to attend to one's level of professional competence. Like their clients, psychologists are vulnerable to distress and diminished functioning caused by a life-threatening illness. Psychologists have an ethical responsibility to monitor and ensure professional competence, yet the distress and distraction that accompany serious health problems can inhibit and undermine self-assessments of competence in many ways; distressed psychologists may react with denial, shame, fear, and problematic countertransference responses. The limitations associated with evaluating competence in the context of distress are discussed and several recommendations are offered for psychologists who deliver services, support gravely ill colleagues, and serve in credentialing and regulatory capacities. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Polycrystalline Silicon-Film™ Thin-film Solar Cells: Advanced Products

Thin-film polycrystalline silicon has the potential to achieve the cost reduction and performance improvement necessary for large-scale electricity markets. Reduced cost is achieved by capitalizing on the benefits of thin films grown on low-cost, large-area substrates. Improved efficiency is realized, in spite of reduced material quality, by incorporating enhanced optical absorption and back-surface passivation. The cornerstone of AstroPower's thin-film solar cell technology is the Silicon-Film™ process: a method for the manufacture of solar cell-quality, polycrystalline films of silicon on a variety of low-cost, supporting substrates. Three thin-film solar cell designs, based on this technology, are currently under development. This paper presents the key design features of these three products and briefly reviews the current status of the development of the key technologies that comprise the advanced thin-film solar cell products.