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Common Situation (common + situation)
Selected AbstractsGuanine-Based Biogenic Photonic-Crystal Arrays in Fish and SpidersADVANCED FUNCTIONAL MATERIALS, Issue 2 2010Avital Levy-Lior Abstract Biological photonic systems composed of anhydrous guanine crystals evolved separately in several taxonomic groups. Here, two such systems found in fish and spiders, both of which make use of anhydrous guanine crystal plates to produce structural colors, are examined. Measurements of the photonic-crystal structures using cryo-SEM show that the crystal plates in both fish skin and spider integument are ,20-nm thick. The reflective unit in the fish comprises stacks of single plates alternating with ,230-nm-thick cytoplasm layers. In the spiders the plates are formed as doublet crystals, cemented by 30-nm layers of amorphous guanine, and are stacked with ,200,nm of cytoplasm between crystal doublets. They achieve light reflective properties through the control of crystal morphology and stack dimensions, reaching similar efficiencies of light reflectivity in both fish skin and spider integument. The structure of guanine plates in spiders are compared with the more common situation in which guanine occurs in the form of relatively unorganized prismatic crystals, yielding a matt white coloration. [source] Some results on the accuracy of an edge-based finite volume formulation for the solution of elliptic problems in non-homogeneous and non-isotropic mediaINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS, Issue 3 2009Darlan Karlo Elisiário de Carvalho Abstract The numerical simulation of elliptic type problems in strongly heterogeneous and anisotropic media represents a great challenge from mathematical and numerical point of views. The simulation of flows in non-homogeneous and non-isotropic porous media with full tensor diffusion coefficients, which is a common situation associated with the miscible displacement of contaminants in aquifers and the immiscible and incompressible two-phase flow of oil and water in petroleum reservoirs, involves the numerical solution of an elliptic type equation in which the diffusion coefficient can be discontinuous, varying orders of magnitude within short distances. In the present work, we present a vertex-centered edge-based finite volume method (EBFV) with median dual control volumes built over a primal mesh. This formulation is capable of handling the heterogeneous and anisotropic media using structured or unstructured, triangular or quadrilateral meshes. In the EBFV method, the discretization of the diffusion term is performed using a node-centered discretization implemented in two loops over the edges of the primary mesh. This formulation guarantees local conservation for problems with discontinuous coefficients, keeping second-order accuracy for smooth solutions on general triangular and orthogonal quadrilateral meshes. In order to show the convergence behavior of the proposed EBFV procedure, we solve three benchmark problems including full tensor, material heterogeneity and distributed source terms. For these three examples, numerical results compare favorably with others found in literature. A fourth problem, with highly non-smooth solution, has been included showing that the EBFV needs further improvement to formally guarantee monotonic solutions in such cases. Copyright © 2008 John Wiley & Sons, Ltd. [source] Faking on Personality Measures: Implications for selection involving multiple predictorsINTERNATIONAL JOURNAL OF SELECTION AND ASSESSMENT, Issue 1 2009Patrick D. Converse The potential for faking on noncognitive measures in high stakes testing situations remains a concern for many selection researchers and practitioners. However, the majority of previous research examining the practical effects of faking on noncognitive assessments has focused on these measures in isolation, rather than the more common situation in which they are used in combination with other predictors. The present simulation examined the effects of faking on a conscientiousness measure on criterion-related validity, mean performance of those selected, and selection decision consistency when hiring decisions were based on this measure alone vs in combination with two other predictors across a range of likely selection scenarios. Overall, results indicated that including additional predictors substantially reduced , but did not eliminate , the negative effects of faking. Faking effects varied across outcomes and selection scenarios, with effects ranging from trivial to noteworthy even for multiple-predictor selection. Implications for future research and practice are discussed. [source] Heteroplasmy in Hair: Study of Mitochondrial DNA Third Hypervariable Region in Hair and Blood Samples,JOURNAL OF FORENSIC SCIENCES, Issue 3 2010Greiciane G. Paneto M.Sc. Abstract:, Mitochondrial DNA (mtDNA) analysis has proved useful for forensic identification especially in cases where nuclear DNA is not available, such as with hair evidence. Heteroplasmy, the presence of more than one type of mtDNA in one individual, is a common situation often reported in the first and second mtDNA hypervariable regions (HV1/HV2), particularly in hair samples. However, there is no data about heteroplasmy frequency in the third mtDNA hypervariable region (HV3). To investigate possible heteroplasmy hotspots, HV3 from hair and blood samples of 100 individuals were sequenced and compared. No point heteroplasmy was observed, but length heteroplasmy was, both in C-stretch and CA repeat. To observe which CA "alleles" were present in each tissue, PCR products were cloned and re-sequenced. However, no variation among CA alleles was observed. Regarding forensic practice, we conclude that point heteroplasmy in HV3 is not as frequent as in the HV1/HV2. [source] Ficus racemosa is pollinated by a single population of a single agaonid wasp species in continental South-East AsiaMOLECULAR ECOLOGY, Issue 13 2010N. KOBMOO Abstract High specificity in the Ficus -agaonid wasp mutualism has lead to the assumption of a mostly ,one-to-one' relationship, albeit with some exceptions. This view has been challenged by new molecular data in recent years, but surprisingly little is known about local and spatial genetic structuring of agaonid wasp populations. Using microsatellite markers, we analysed genetic structuring of Ceratosolen fusciceps, the fig wasp pollinating Ficus racemosa, a fig tree species widely distributed from India to Australia. In sampling stretching from the south of China to the south of Thailand we found evidence for only a single pollinating wasp species in continental South-East Asian mainland. We found no evidence for the co-occurrence of cryptic species within our subcontinent sampling zone. We observed no spatial genetic structure within sites and only limited structuring over the whole sampling zone, suggesting that F. racemosa is pollinated by a single population of a single agaonid wasp species all over continental South-East Asia. An additional sample of wasps collected on F. racemosa in Australia showed clear-cut genetic differentiation from the Asian continent, suggesting allopatric divergence into subspecies or species. We propose that the frequent local co-occurrence of sister species found in the literature mainly stems from contact zones between biogeographic regions, and that a single pollinator species over wide areas might be the more common situation everywhere else. [source] Heritabilities and quantitative trait loci for blood gases and blood pH in swineANIMAL GENETICS, Issue 2 2009G. Reiner Summary Maintaining pH and blood gases in a narrow range is essential to sustain normal biochemical reactions. Decreased oxygenation, poor tissue perfusion, disturbance to CO2 expiration, and shortage of HCO3, can lead to metabolic acidosis. This is a common situation in swine, and originates from a broad range of medical conditions. pH and blood gases appear to be under genetic control, and populations with physiological traits closer to the pathological thresholds may be more susceptible to developing pathological conditions. However, little is known about the genetic basis of such traits. We have therefore estimated phenotypic and genetic variability and identified quantitative trait loci (QTL) for pH and blood gases in blood samples from 139 F2 pigs from the Meishan/Pietrain family. Samples were taken before and after challenge with Sarcocystis miescheriana, a protozoan parasite of muscle. Twenty-seven QTL influencing pH and blood gases were identified on nine chromosomes. Five of the QTL were significant on a genome-wide level; 22 QTL were significant on a chromosome-wide level. QTL for pH-associated traits have been mapped to SSC3, 18 and X. QTL associated with CO2 have been detected on SSC6, 7, 8 and 9, and QTL associated with O2 on SSC2 and SSC8. QTL showed specific health/disease patterns that were related to the physiological state of the pigs from day 0, to acute disease (day 14), convalescence (day 28) and chronic disease (day 42). The results demonstrate that pH and blood gases are influenced by multiple chromosomal areas, each with relatively small effects. [source] Ligand Association/Dissociation Paths and Ill-Defined Coordination NumbersCHEMISTRY - A EUROPEAN JOURNAL, Issue 22 2010Antonio Ruiz-Martínez Abstract The continuous shape measures approach provides a means for handling the common situation in which a metal atom presents an ill-defined coordination number. Those cases are characterized by the presence of secondary interactions to Lewis bases at distances significantly longer than those expected for a chemical bond. Systematic ways of analyzing ligand association/dissociation pathways that describe such structures and their application to a variety of specific cases are presented. The concepts and methodology presented here apply to molecules and extended solids as well and provide, when needed, a more flexible and precise stereochemical description of the metal coordination sphere than that of an integer coordination number and the associated polyhedral shape. El mètode de les mesures contínues de forma ens permet tractar la situació trobada freqüentment, en què un àtom metàl,lic presenta un nombre de coordinació no ben definit, caracteritzat per la presència d,interaccions secundàries amb bases de Lewis a distàncies significativament més llargues que les que correspondrien a un enllaç químic. Aquí es presenten formes sistemàtiques d,analitzar els camins d,associació/dissociació de lligands que descriuen aquestes estructures, així com llur aplicació a diverses famílies de compostos. Els conceptes i la metodologia presentats en aquest article s'apliquen tant a molècules com a sòlids infinits i ens proporcionen una descripció estereoquímica més flexible i alhora precisa de les esferes de coordinació que no pas un nombre de coordinació enter i la forma polièdrica associada. [source] The Effects of Severity of Failure and Customer Loyalty on Service Recovery StrategiesPRODUCTION AND OPERATIONS MANAGEMENT, Issue 4 2004Christopher W. Craighead Service failures do not need to result in permanent negative consequences as long as effective recovery activities are undertaken. Unfortunately, existing research has been limited in providing information to support prescriptive approaches for applying specific service recovery techniques. By using data from a large sample (n = 861) of service failure incidents and employing the use of hierarchical and non-hierarchical cluster analysis, this exploratory study creates and analyzes empirical types of service failures. The derived failure types, or common situations faced by service providers, focus on customer loyalty and the severity of the failure, and may be visualized in a two-by-two matrix. Regression analysis is then used to demonstrate how effective recovery strategies and supporting activities should vary, based on the location of the failure within the matrix. The approach and results offer important implications for strategy and service support activities as well as a foundation for systematizing service recovery efforts. [source] The impact of sildenafil citrate on sexual satisfaction profiles in men with a penile prosthesis in situBJU INTERNATIONAL, Issue 1 2004J.P. Mulhall This section includes three papers, two of which describe the use of drug treatment for erectile dysfunction in special situations. The authors from New York and Chicago write about sildenafil in patients with a penile prosthesis in situ. Authors from Zurich have used apomorphine in patients with spinal cord injury and erectile dysfunction. It is often helpful to readers with an interest in the area of erectile problems to explore the use of commonly prescribed drugs in somewhat less common situations. OBJECTIVE To assess the efficacy of sildenafil in increasing penile glans tumescence and improving patient satisfaction in men with a penile prosthesis, as this remains a major treatment for erectile dysfunction but a common complaint is the lack of glans engorgement. PATIENTS AND METHODS To determine whether sildenafil combined with a penile prosthesis improves satisfaction, patients used an implant alone for at least 1 month, after which they completed the International Index of Erectile Function (IIEF) questionnaire. The same patients were then given sildenafil citrate and completed the IIEF questionnaire after using the sildenafil/implant combination. RESULTS Patients who responded to sildenafil with glans engorgement reported significantly greater satisfaction scores than with an implant alone. CONCLUSION We currently offer sildenafil citrate after implantation to all men who have a penile prosthesis placed. [source] | ||||||||||||||||