Diffusing-CRN k-means: an improved k-means clustering algorithm applied in cognitive radio ad hoc networks

With increasing demand of new wireless applications and increasing number of wireless user’s, problem of spectrum scarcity arises. In this context, cognitive radio supports dynamic spectrum access to address spectrum scarcity problem. Cognitive radio defined the cognitive radio nodes by their ability to intelligently adapt the environment to achieve specific objectives through advanced techniques. The variance of channel availability for cognitive radio nodes degrades connectivity and robustness of this type of network; in this case the use of clustering is an effective approach to meet this challenge. Indeed, the geographical areas are homogeneous in terms of type of radio spectrum, radio resources are better allocated by grouping cognitive radio nodes per cluster. Clustering is interesting to effectively manage the spectrum or routing in cognitive radio ad hoc networks. In this paper, we aim to improve connectivity and cooperativeness of cognitive radio nodes based on the improvement of the k-means algorithm. Our proposed algorithm is applied in cognitive radio ad hoc networks. The obtained results in terms of exchange messages and execution time show the feasibility of our algorithm to form clusters in order to improve connectivity and cooperativeness of cognitive radio nodes in the context of cognitive radio ad hoc networks.     

Meaningful performance evaluation conditions for fire service thermal imaging cameras

Thermal imaging cameras (TIC) are rapidly becoming integral equipment for the fire service for use in structure fires and other emergencies. The Building and Fire Research Laboratory (BFRL) at the National Institute of Standards and Technology has conducted research to establish test conditions that best represent the environment in which TIC are used. Firefighters may use TIC for field operations ranging from fire attack, search/rescue, hot spot detection, overhaul activities, to detecting the location of hazardous materials.To develop standardized TIC performance metrics and test methods that capture the harsh environment in which TIC may be used, information was collected from users, the literature, and from fire tests conducted at BFRL. A workshop was held to facilitate knowledge transfer from the fire service and TIC manufacturers. Full-scale and bench-scale experimental work focused on temperature extremes and the presence of obscuring media such as smoke, dust and water. Consolidation of fire environment data with fire fighting operations and imaging needs resulted in a set of performance metrics and test methods that relate to the conditions and tasks encountered by firefighters in structural fire fighting applications. This work is included in a new draft standard on fire service TIC.     

Cognitive behavioral guided self-help for the treatment of recurrent binge eating.

Objective: Despite proven efficacy of cognitive behavioral therapy (CBT) for treating eating disorders with binge eating as the core symptom, few patients receive CBT in clinical practice. Our blended efficacy–effectiveness study sought to evaluate whether a manual-based guided self-help form of CBT (CBT-GSH), delivered in 8 sessions in a health maintenance organization setting over a 12-week period by master's-level interventionists, is more effective than treatment as usual (TAU). Method: In all, 123 individuals (mean age = 37.2; 91.9% female, 96.7% non-Hispanic White) were randomized, including 10.6% with bulimia nervosa (BN), 48% with binge eating disorder (BED), and 41.4% with recurrent binge eating in the absence of BN or BED. Baseline, posttreatment, and 6- and 12-month follow-up data were used in intent-to-treat analyses. Results: At 12-month follow-up, CBT-GSH resulted in greater abstinence from binge eating (64.2%) than TAU (44.6%; number needed to treat = 5), as measured by the Eating Disorder Examination (EDE). Secondary outcomes reflected greater improvements in the CBT-GSH group in dietary restraint (d = 0.30); eating, shape, and weight concern (ds = 0.54, 1.01, 0.49, respectively; measured by the EDE Questionnaire); depression (d = 0.56; Beck Depression Inventory); and social adjustment (d = 0.58; Work and Social Adjustment Scale), but not weight change. Conclusions: CBT-GSH is a viable first-line treatment option for the majority of patients with recurrent binge eating who do not meet diagnostic criteria for BN or anorexia nervosa. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

DXP Synthase‐Catalyzed C?N Bond Formation: Nitroso Substrate Specificity Studies Guide Selective Inhibitor Design

1‐Deoxy‐D ‐xylulose 5‐phosphate (DXP) synthase catalyzes the first step in the nonmammalian isoprenoid biosynthetic pathway to form DXP from pyruvate and D ‐glyceraldehyde 3‐phosphate (D ‐GAP) in a thiamin diphosphate‐dependent manner. Its unique structure and mechanism distinguish DXP synthase from its homologues and suggest that it should be pursued as an anti‐infective drug target. However, few reports describe any development of selective inhibitors of this enzyme. Here, we reveal that DXP synthase catalyzes C? N bond formation and exploit aromatic nitroso substrates as active site probes. Substrate specificity studies reveal a high affinity of DXP synthase for aromatic nitroso substrates compared to the related ThDP‐dependent enzyme pyruvate dehydrogenase (PDH). Results from inhibition and mutagenesis studies indicate that nitroso substrates bind to E. coli DXP synthase in a manner distinct from that of D ‐GAP. Our results suggest that the incorporation of aryl acceptor substrate mimics into unnatural bisubstrate analogues will impart selectivity to DXP synthase inhibitors. As a proof of concept, we show selective inhibition of DXP synthase by benzylacetylphosphonate (BnAP).     

Characterization of mechanical properties of suspension plasma sprayed TiO2 coatings using scratch test

The study aimed at characterizing mechanical properties of TiO₂ coatings obtained by the use of aqueous suspensions of fine rutile and anatase particles onto metal substrates. Thickness of the coatings was found with the use of optical microscope observations of metallographical cross-sections. The coatings morphology was found with scanning electron microscope (SEM) and their phase composition was determined by X-ray diffraction method. The mechanical properties were characterized using scratch test. The test enabled to characterize the adhesion of coatings by determination of critical force necessary to peel off the coatings from the substrate and, on the other hand, to estimate their cohesion by the measurement of the scratch hardness. The hardness was calculated using the width of the scratch and the value of force applied. The design of experiments (DOE) of spraying with the use of a 2³ full factorial plan was applied to rutile powder. The coatings were sprayed onto aluminium substrate. The DOE enabled to find the effects of three principal parameters, i.e. electric power input to plasma, spray distance and suspension feed rate onto coating adhesion expressed by critical force. A preliminary data for anatase powder sprayed with one set of operational parameters onto stainless steel substrate are also shown.     

Privation relative et programmes d'action positive.

Studied the effects of fraternal relative deprivation (FRD) and relative deprivation on behalf of others (RDO) on the promotion of equality in the work force and participation in affirmative action programs by men and women. Human subjects: 89 male and female French adults (aged 18 yrs and older) (university students). The Ss were given a questionnaire on the situation of women in the work force that asked questions on the cognitive and affective dimensions of relative deprivation, behaviors related to promotion of equality of the sexes, and reactions to programs of affirmative action. Factors associated with FRD and with RDO were determined and analyzed statistically according to age, sex, and social priorities. (English abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)