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Manner Consistent (manner + consistent)
Selected AbstractsReputation Formalization for an Information,Sharing Multi,Agent SystemCOMPUTATIONAL INTELLIGENCE, Issue 4 2002Jonathan Carter We propose that through the formalization of concepts related to trust, a more accurate model of trust can be implemented. This paper presents a new model of trust that is based on the formalization of reputation. A multidisciplinary approach is taken to understanding the nature of trust and its relation to reputation. Through this approach, a practical definition of reputation is adopted from sociological contexts and a model of reputation is designed and presented. Reputation is defined as role fulfillment. To formalize reputation, it is necessary to formalize the expectations placed upon an agent within a particular multi,agent system (MAS). In this case, the agents are part of an information,sharing society. Five roles are defined along with the ways in which these roles are objectively fulfilled. Through the measurement of role fulfillment, a vector representing reputation can be developed. This vector embodies the magnitude of the reputation and describes the patterns of behavior associated with the direction of the vector. Experiments are conducted to verify the sensibility of the proposed models for role fulfillment and overall reputation. The simulation results show that the roles, defined for building reputation in an information,sharing MAS environment, react to different agent and user actions in a manner consistent with the formal definitions. [source] SPARC is expressed by macroglia and microglia in the developing and mature nervous systemDEVELOPMENTAL DYNAMICS, Issue 5 2008Adele J. Vincent Abstract SPARC (secreted protein, acidic and rich in cysteine) is a matricellular protein that is highly expressed during development, tissue remodeling, and repair. SPARC produced by olfactory ensheathing cells (OECs) can promote axon sprouting in vitro and in vivo. Here, we show that in the developing nervous system of the mouse, SPARC is expressed by radial glia, blood vessels, and other pial-derived structures during embryogenesis and postnatal development. The rostral migratory stream contains SPARC that becomes progressively restricted to the SVZ in adulthood. In the adult CNS, SPARC is enriched in specialized radial glial derivatives (Müller and Bergmann glia), microglia, and brainstem astrocytes. The peripheral glia, Schwann cells, and OECs express SPARC throughout development and in maturity, although it appears to be down-regulated with maturation. These data suggest that SPARC may be expressed by glia in a spatiotemporal manner consistent with a role in cell migration, neurogenesis, synaptic plasticity, and angiogenesis. Developmental Dynamics 237:1449-1462, 2008. © 2008 Wiley-Liss, Inc. [source] Restoring sanitation services after an earthquake: field experience in Bam, IranDISASTERS, Issue 3 2005Jean-François Pinera Abstract A powerful earthquake hit the city of Bam in southeast Iran on 26 December 2003. In its aftermath, a number of international relief agencies, including Oxfam, assisted in providing emergency sanitation services. Oxfam's programme consisted of constructing and repairing toilets and showers in villages located outside of the city. In contrast with other organisations, Oxfam opted for brickwork structures, using local materials and human resources rather than prefabricated cubicles. The choice illustrates the dilemmas faced by agencies involved in emergency sanitation: responding to needs in a manner consistent with international standards and offering assistance in a timely fashion while involving beneficiaries. Following a preliminary survey, Oxfam concluded that the provision of showers and latrines, in addition to utilisation of local materials and human resources, was essential for ensuring well-being, empowerment and dignity among members of the affected population, thereby maximising the benefits. [source] Turbulent flow over a dune: Green River, ColoradoEARTH SURFACE PROCESSES AND LANDFORMS, Issue 3 2005Jeremy G. Venditti Abstract Detailed echo-sounder and acoustic Doppler velocimeter measurements are used to assess the temporal and spatial structure of turbulent flow over a mobile dune in a wide, low-gradient, alluvial reach of the Green River. Based on the geometric position of the sensor over the bedforms, measurements were taken in the wake, in transitional flow at the bedform crest, and in the internal boundary layer. Spatial distributions of Reynolds shear stress, turbulent kinetic energy, turbulence intensity, and correlation coefficient are qualitatively consistent with those over fixed, two-dimensional bedforms in laboratory flows. Spectral and cospectral analysis demonstrates that energy levels in the lee of the crest (i.e. wake) are two to four times greater than over the crest itself, with minima over the stoss slope (within the developing internal boundary layer). The frequency structure in the wake is sharply defined with single, dominant peaks. Peak and total spectral and cross-spectral energies vary over the bedform in a manner consistent with wave-like perturbations that ,break' or ,roll up' into vortices that amalgamate, grow in size, and eventually diffuse as they are advected downstream. Fluid oscillations in the lee of the dune demonstrate Strouhal similarity between laboratory and field environments, and correspondence between the peak frequencies of these oscillations and the periodicity of surface boils was observed in the field. Copyright © 2005 John Wiley & Sons, Ltd. [source] Effects of plant diversity, plant productivity and habitat parameters on arthropod abundance in montane European grasslandsECOGRAPHY, Issue 4 2005Jörg Perner Arthropod abundance has been hypothesized to be correlated with plant diversity but the results of previous studies have been equivocal. In contrast, plant productivity, vegetation structure, abiotic site conditions, and the physical disturbance of habitats, are factors that interact with plant diversity, and that have been shown to influence arthropod abundance. We studied the combined effect of plant species diversity, productivity and site characteristics on arthropod abundance in 71 managed grasslands in central Germany using multivariate statistics. For each site we determined plant species cover, plant community biomass (productivity), macro- and micronutrients in the soil, and characterized the location of sites with respect to orographic parameters as well as the current and historic management regimes. Arthropods were sampled using a suction sampler and classified a priori into functional groups (FGs). We found that arthropod abundance was not correlated with plant species richness, effective diversity or Camargo's evenness, even when influences of environmental variables were taken into account. In contrast, plant community composition was highly correlated with arthropod abundances. Plant community productivity influenced arthropod abundance but explained only a small proportion of the variance. The abundances of the different arthropod FGs were influenced differentially by agricultural management, soil characteristics, vegetation structure and by interactions between different FGs of arthropods. Herbivores, carnivores and detritivores reacted differently to variation in environmental variables in a manner consistent with their feeding mode. Our results show that in natural grassland systems arthropod abundance is not a simple function of plant species richness, and they emphasize the important role of plant community composition for the abundance patterns of the arthropod assemblages. [source] The Habitats Directive as an instrument to achieve sustainability?ENVIRONMENTAL POLICY AND GOVERNANCE, Issue 3 2006An analysis through the case of the Rotterdam Mainport Development Project Abstract The Habitats Directive is a key document for the protection of critical natural capital in the European Union. In a manner consistent with the understanding of sustainability in the European Commission, even critical natural capital is subject to trade-offs in favour of economic and social development. This is reflected in Articles 6(3) and 6(4) of the directive. This paper analyses the planning process leading to the approval of the expansion of the port of Rotterdam project , which will significantly affect Natura 2000 , against sustainability criteria. Although it shows that the directive is powerful to promote sustainable planning, the success of the case study was due mainly to elements specific to the particular planning process, namely the use of deliberative public participation mechanisms as well as specific assessment tools. Lessons are drawn and recommendations made to strengthen the Habitats Directive and the national planning processes in relation to projects potentially affecting Natura 2000 sites. Copyright © 2006 John Wiley & Sons, Ltd and ERP Environment. [source] Attitude-behaviour consistency: the role of group norms, attitude accessibility, and mode of behavioural decision-makingEUROPEAN JOURNAL OF SOCIAL PSYCHOLOGY, Issue 5 2003Joanne R. Smith The interplay between two perspectives that have recently been applied in the attitude area,the social identity approach to attitude-behaviour relations (Terry & Hogg, 1996) and the MODE model (Fazio, 1990a),was examined in the present research. Two experimental studies were conducted to examine the role of group norms, group identification, attitude accessibility, and mode of behavioural decision-making in the attitude-behaviour relationship. In Study 1 (N,=,211), the effects of norms and identification on attitude-behaviour consistency as a function of attitude accessibility and mood were investigated. Study 2 (N,=,354) replicated and extended the first experiment by using time pressure to manipulate mode of behavioural decision-making. As expected, the effects of norm congruency varied as a function of identification and mode of behavioural decision-making. Under conditions assumed to promote deliberative processing (neutral mood/low time pressure), high identifiers behaved in a manner consistent with the norm. No effects emerged under positive mood and high time pressure conditions. In Study 2, there was evidence that exposure to an attitude-incongruent norm resulted in attitude change only under low accessibility conditions. The results of these studies highlight the powerful role of group norms in directing individual behaviour and suggest limited support for the MODE model in this context. Copyright © 2003 John Wiley & Sons, Ltd. [source] DOES VARIATION IN SELECTION IMPOSED BY BEARS DRIVE DIVERGENCE AMONG POPULATIONS IN THE SIZE AND SHAPE OF SOCKEYE SALMON?EVOLUTION, Issue 5 2009Stephanie M. Carlson Few studies have determined whether formal estimates of selection explain patterns of trait divergence among populations, yet this is one approach for evaluating whether the populations are in equilibria. If adaptive divergence is complete, directional selection should be absent and stabilizing selection should prevail. We estimated natural selection, due to bear predation, acting on the body size and shape of male salmon in three breeding populations that experience differing predation regimes. Our approach was to (1) estimate selection acting within each population on each trait based on an empirical estimate of reproductive activity, (2) test for trait divergence among populations, and (3) test whether selection coefficients were correlated with trait divergence among populations. Stabilizing selection was never significant, indicating that these populations have yet to attain equilibria. Directional selection varied among populations in a manner consistent with trait divergence, indicating ongoing population differentiation. Specifically, the rank order of the creeks in terms of patterns of selection paralleled the rank order in terms of size and shape. The shortest and least deep-bodied males had the highest reproductive activity in the creek with the most intense predation and longer and deeper-bodied males were favored in the creeks with lower predation risk. [source] Systemic induced resistance in Monterey pineFOREST PATHOLOGY, Issue 2 2001Bonello The pathogenic fungus Fusarium circinatum causes pitch canker of pines. This study shows that Monterey pine (Pinus radiata), one of the most economically important pine species in the world and the main host in California, responds to infection by Fusarium circinatum in a manner consistent with systemic induced resistance. Repeated mechanical inoculations of the same trees in the field produced progressively smaller lesions over a period of 2 years, with mean lesion length decreasing significantly from 2.89 ± 0.42 cm to 1.04 ± 0.17 cm. In the greenhouse, predisposing inoculations with the pathogen induced a significant lesion length reduction, from 5.5 ± 0.21 cm in control trees to 4.46 ± 0.36 cm in predisposed trees over a period of 6 weeks. Under constant environmental conditions in a growth chamber, predisposing inoculations also induced a significant reduction in lesion size, from 3.01 ± 0.15 cm to 2.55 ± 0.18 cm over a period of 4 weeks. This is the first unequivocal report of systemic induced resistance in a conifer. Résistance systémique induite chez le Pinus radiata Fusarium circinatum est l'agent causal du ,pitch canker' des pins. Le Pinus radiata est l'un des pins les plus importants économiquement dans le monde, et le principal hôte de la maladie en Californie. Cette étude montre que P. radiata réagit régulièrement à l'infection de Fusarium circinatum d'une façon qui peut être de la résistance systémique induite. Des inoculations mécaniques répétées sur de mêmes arbres en nature ont produit progressivement des lésions dont la taille diminuait au cours d'une période de deux ans; la longueur des lésions diminuait significativement de 2.89 ± 0.42 cm à 1.04 ± 0.17 cm. En serre, des inoculations de pré-conditionnement avec le parasite ont entraîné une réduction significative de la longueur des lésions, de 5.5 ± 0.21 cm chez les témoins à 4.46 ± 0.36 cm chez les arbres pré-conditionnés, au cours d'une période de six semaines. En conditions environnementales constantes en chambre climatique, les inoculations de pré-conditionnement ont aussi induit une réduction significative de la taille des lésions, de 3.01 ± 0.15 cm à 2.55 ± 0.18 cm, en une période de 4 semaines. Ceci est la première mention non équivoque d'une résistance systémique induite chez un conifère. Induzierte systemische Resistenz in Monterey-Kiefer Der pathogene Pilz Fusarium circinatum verursacht einen Krebs an Kiefern (pitch canker). Die vorliegende Untersuchung zeigt, dass die Monterey-Kiefer (Pinus radiata), eine der ökonomisch wichtigsten Kiefernarten der Welt und Hauptwirt in Kalifornien, auf Infektionen durch Fusarium circinatum mit induzierter systemischer Resistenz reagiert. Wiederholte mechanische Inokulationen der gleichen Bäume im Feld führten zu zunehmend kleineren Läsionen über einen Beobachtungszeitraum von zwei Jahren. Die Länge der Läsionen nahm von 2.89 ± 0.42 cm auf 1.04 ± 0.17 cm signifikant ab. Im Gewächshaus bewirkten prädisponierende Inokulationen mit dem Pathogen eine signifikante Reduktion der Läsionslänge von 5.5 ± 0.21 cm in den Kontrollen auf 4.46 ± 0.36 cm in den prädisponierten Pflanzen über einen Beobachtungszeitraum von sechs Wochen. Prädisponierende Inokulationen bewirkten auch unter konstanten Umweltbedingungen in einer Klimakammer eine signifikante Abnahme der Läsionsgrösse von 3.01 ± 0.15 cm auf 2.55 ± 0.18 über eine Periode von vier Wochen. Es handelt sich hier um den ersten eindeutigen Nachweis von induzierter systemischer Resistenz bei einer Konifere. [source] Rapid Generation of Biologically Relevant Hydrogels Containing Long-Range Chemical GradientsADVANCED FUNCTIONAL MATERIALS, Issue 1 2010Jiankang He Abstract Many biological processes are regulated by gradients of bioactive chemicals. Thus, the generation of materials with embedded chemical gradients may be beneficial for understanding biological phenomena and generating tissue-mimetic constructs. Here a simple and versatile method to rapidly generate materials containing centimeter-long gradients of chemical properties in a microfluidic channel is described. The formation of a chemical gradient is initiated by a passive-pump-induced forward flow and further developed during an evaporation-induced backward flow. The gradient is spatially controlled by the backward flow time and the hydrogel material containing the gradient is synthesized via photopolymerization. Gradients of a cell-adhesion ligand, Arg-Gly-Asp-Ser (RGDS), are incorporated in poly(ethylene glycol)-diacrylate (PEG-DA) hydrogels to test the response of endothelial cells. The cells attach and spread along the hydrogel material in a manner consistent with the RGDS-gradient profile. A hydrogel containing a PEG-DA concentration gradient and constant RGDS concentration is also shown. The morphology of cells cultured on such hydrogel changes from round in the lower PEG-DA concentration regions to well-spread in the higher PEG-DA concentration regions. This approach is expected to be a valuable tool to investigate the cell,material interactions in a simple and high-throughput manner and to design graded biomimetic materials for tissue engineering applications. [source] Olfactory information saves venom during prey-capture of the hunting spider Cupiennius salei (Araneae: Ctenidae)FUNCTIONAL ECOLOGY, Issue 2 2006S. HOSTETTLER Summary 1The Neotropical spider Cupiennius salei Keyserling (Ctenidae) selects prey in a manner consistent with the amount of venom available in its venom glands. It distinguishes the venom sensitivity of different prey species, and uses its venom economically (according to the venom-optimization hypothesis). 2A prey-choice experiment was performed to test whether spiders use olfactory cues to detect prey and select prey items that are appropriate for their amount of available venom. 3The spider could choose between two similar prey dummies made of agar. We added the odour of two prey species, either by adding minced insects to an agar block or by offering it on filter paper which had previously been exposed to the living prey. Cupiennius salei spiders had either full or emptied venom glands. 4Two insects of distinctive venom sensitivity, but high acceptance, were tested: a sensitive cricket and a less sensitive cockroach. 5Using video surveillance, we found an attraction effect of prey odour in the prey-capture behaviour of C. salei. Spiders preferred agar pieces with minced insects or insect odour on filter paper over non-smelling items. Reaction frequency and attack rates were equal for spiders with full venom glands if they had to choose between cricket and cockroach odour. When the venom glands were empty, however, C. salei significantly preferred the venom-sensitive cricket over the venom-insensitive cockroach. 6We showed for the first time that C. salei uses its olfactory sense to detect prey items, and distinguishes between prey species with low and high sensitivity to spider venom. This study supports the venom-optimization hypothesis. [source] Why Strikes Occur: Evidence from the Capital MarketsINDUSTRIAL RELATIONS, Issue 1 2002Jonathan K. Kramer New and existing empirical evidence regarding the stock market reaction to strikes is used to test the validity of three strike theories. A review of the existing capital market evidence reveals the need for information regarding the intraindustry announcement effects of strikes against manufacturing firms. This need is filled by applying event-study methodology, in a manner consistent with earlier studies, to a sample of strikes during the period 1982,1999. This new evidence, combined with that of previous studies, consistently supports the validity of Hick's theory that strikes are the result of bargaining errors, misperceptions of bargaining goals, or discrepancies between the expectations of union leaders and the rank and file. [source] Effect of spatial variability of cross-correlated soil properties on bearing capacity of strip footingINTERNATIONAL JOURNAL FOR NUMERICAL AND ANALYTICAL METHODS IN GEOMECHANICS, Issue 1 2010Sung Eun Cho Abstract Geotechnical engineering problems are characterized by many sources of uncertainty. Some of these sources are connected to the uncertainties of soil properties involved in the analysis. In this paper, a numerical procedure for a probabilistic analysis that considers the spatial variability of cross-correlated soil properties is presented and applied to study the bearing capacity of spatially random soil with different autocorrelation distances in the vertical and horizontal directions. The approach integrates a commercial finite difference method and random field theory into the framework of a probabilistic analysis. Two-dimensional cross-correlated non-Gaussian random fields are generated based on a Karhunen,Loève expansion in a manner consistent with a specified marginal distribution function, an autocorrelation function, and cross-correlation coefficients. A Monte Carlo simulation is then used to determine the statistical response based on the random fields. A series of analyses was performed to study the effects of uncertainty due to the spatial heterogeneity on the bearing capacity of a rough strip footing. The simulations provide insight into the application of uncertainty treatment to geotechnical problems and show the importance of the spatial variability of soil properties with regard to the outcome of a probabilistic assessment. Copyright © 2009 John Wiley & Sons, Ltd. [source] Phylogeographic structuring and volant mammals: the case of the pallid bat (Antrozous pallidus)JOURNAL OF BIOGEOGRAPHY, Issue 7 2007Sarah E. Weyandt Abstract Aim, To examine the phylogeographic pattern of a volant mammal at the continental scale. The pallid bat (Antrozous pallidus) was chosen because it ranges across a zone of well-studied biotic assemblages, namely the warm deserts of North America. Location, The western half of North America, with sites in Mexico, the United States, and Canada. Methods, PCR amplification and sequencing of the mitochondrial control region was performed on 194 pallid bats from 36 localities. Additional sequences at the cytochrome- b locus were generated for representatives of each control-region haplotype. modeltest was used to determine the best set of parameters to describe each data set, which were incorporated into analyses using paup*. Statistical parsimony and measurements of population differentiation (amova, FST) were also used to examine patterns of genetic diversity in pallid bats. Results, We detected three major lineages in the mitochondrial DNA of pallid bats collected across the species range. These three major clades have completely non-overlapping geographic ranges. Only 6 of 80 control-region haplotypes were found at more than a single locality, and sequences at the more conserved cytochrome- b locus revealed 37 haplotypes. Statistical parsimony generated three unlinked networks that correspond exactly to clades defined by the distance-based analysis. On average there was c. 2% divergence for the combined mitochondrial sequences within each of the three major clades and c. 7% divergence between each pair of clades. Molecular clocks date divergence between the major clades at more than one million years, on average, using the faster rates, and at more than three million years using more conservative rates of evolution. Main conclusions, Divergent haplotypic lineages with allopatric distributions suggest that the pallid bat has responded to evolutionary pressures in a manner consistent with other taxa of the American southwest. These results extend the conclusions of earlier studies that found the genetic structuring of populations of some bat species to show that a widespread volant species may comprise a set of geographically replacing monophyletic lineages. Haplotypes were usually restricted to single localities, and the clade showing geographic affinities to the Sonoran Desert contained greater diversity than did clades to the east and west. While faster molecular clocks would allow for glacial cycles of the Pleistocene as plausible agents of diversification of pallid bats, evidence from co-distributed taxa suggests support for older events being responsible for the initial divergence among clades. [source] Periodontal therapy alters gene expression of peripheral blood monocytesJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 9 2007Panos N. Papapanou Abstract Aims: We investigated the effects of periodontal therapy on gene expression of peripheral blood monocytes. Methods: Fifteen patients with periodontitis gave blood samples at four time points: 1 week before periodontal treatment (#1), at treatment initiation (baseline, #2), 6-week (#3) and 10-week post-baseline (#4). At baseline and 10 weeks, periodontal status was recorded and subgingival plaque samples were obtained. Periodontal therapy (periodontal surgery and extractions without adjunctive antibiotics) was completed within 6 weeks. At each time point, serum concentrations of 19 biomarkers were determined. Peripheral blood monocytes were purified, RNA was extracted, reverse-transcribed, labelled and hybridized with AffymetrixU133Plus2.0 chips. Expression profiles were analysed using linear random-effects models. Further analysis of gene ontology terms summarized the expression patterns into biologically relevant categories. Differential expression of selected genes was confirmed by real-time reverse transcriptase-polymerase chain reaction in a subset of patients. Results: Treatment resulted in a substantial improvement in clinical periodontal status and reduction in the levels of several periodontal pathogens. Expression profiling over time revealed more than 11,000 probe sets differentially expressed at a false discovery rate of <0.05. Approximately 1/3 of the patients showed substantial changes in expression in genes relevant to innate immunity, apoptosis and cell signalling. Conclusions: The data suggest that periodontal therapy may alter monocytic gene expression in a manner consistent with a systemic anti-inflammatory effect. [source] Doppler ultrasound assessment of posterior tibial artery size in humansJOURNAL OF CLINICAL ULTRASOUND, Issue 5 2006Manning J. Sabatier PhD Abstract Purpose. The difference between structural remodeling and changes in tone of peripheral arteries in the lower extremities has not been evaluated. The purpose of this study was to (1) evaluate the day-to-day reproducibility and interobserver reliability (IOR) of posterior tibial artery (PTA) diameter measurements and (2) evaluate the effect of posture on PTA diameter at rest (Drest), during 10 minutes of proximal cuff occlusion (Dmin), and after the release of cuff occlusion (Dmax), as well as range (Dmax , Dmin) and constriction [(Dmax , Drest)/(Dmax , Dmin) × 100] in vivo. Methods. We used B-mode sonography to image the PTA during each condition. Results. Day-to-day reliability was good for Drest (intraclass correlation coefficient [ICC] 0.95; mean difference 4.2%), Dmin (ICC 0.93; mean difference 5.4%), and Dmax (ICC 0.99; mean difference 2.2%). The coefficient of repeatability for IOR was 70.5 ,m, with a mean interobserver error of 4.7 ,m. The seated position decreased Drest (2.6 ± 0.2 to 2.4 ± 0.3 mm; p = 0.002), increased Dmin (2.1 ± 0.2 to 2.4 ± 0.2 mm; p = 0.001), and decreased Dmax (3.1 ± 0.4 to 2.8 ± 0.3 mm; p < 0.001) compared with the supine position. The seated position also decreased arterial range (Dmax , Dmin) from 0.9 ± 0.2 to 0.5 ± 0.1 mm (p = 0.003) and increased basal arterial constriction from 57 ± 19% to 105 ± 27% (p = 0.007). Conclusions. The system employed for measuring PTA diameter yields unbiased and consistent estimates. Furthermore, lower extremity arterial constriction and range change with posture in a manner consistent with known changes in autonomic activity. © 2006 Wiley Periodicals, Inc. J Clin Ultrasound 34:223,230, 2006 [source] A Typology of Organizational Membership: Understanding Different Membership Relationships Through the Lens of Social ExchangeMANAGEMENT AND ORGANIZATION REVIEW, Issue 3 2009Christina L. Stamper abstract Using a social exchange perspective and responding to prior calls to separate resources exchanged from the relationship between parties, we develop a relationship typology based on rights and responsibilities arguments. We begin with the idea that various levels and types of rights and responsibilities are the exchange currency utilized by the employer and employee, respectively. Further, the degree to which an organization grants rights to an individual and the degree to which the individual voluntarily accepts responsibilities results in four distinct organizational membership profiles (i.e., peripheral, associate, detached, and full). We believe this membership typology is an important theoretical mechanism that may be used to link the exchange between the employee and employer (as represented by psychological contracts) to psychological attachment (as represented by perceived membership) between these two parties. Specifically, members in each profile will tend to have certain kinds of psychological attachments to the organization, causing them to (i) perceive membership in certain ways and (ii) behave in a manner consistent with that perception. The article concludes by discussing the implications of the propositions for both researchers and practitioners, as well as making suggestions for future research efforts. [source] An agency analysis of church,pastor relationsMANAGERIAL AND DECISION ECONOMICS, Issue 6 2001Charles Zech Incentives are critical to the study of economics. But do they work in non-traditional economic settings, such as religious organizations, in a manner consistent with economic theory? This study considers the agency relationship between churches and their clergy. This paper contends that pastor compensation is not typically tied directly to performance, but rather indirectly through promotion tournaments. Pastors whose performance is recognized as being exceptional are rewarded by being called to larger, more prestigious congregations. Given the difficulty of observing and measuring pastor performance this represents a sensible solution to the church,pastor principal,agent problem. Copyright © 2001 John Wiley & Sons, Ltd. [source] Diversification on an ecologically constrained adaptive landscapeMOLECULAR ECOLOGY, Issue 12 2008GARY A. WELLBORN Abstract We used phylogenetic analysis of body-size ecomorphs in a crustacean species complex to gain insight into how spatial complexity of ecological processes generates and maintains biological diversity. Studies of geographically widespread species of Hyalella amphipods show that phenotypic evolution is tightly constrained in a manner consistent with adaptive responses to alternative predation regimes. A molecular phylogeny indicates that evolution of Hyalella ecomorphs is characterized by parallel evolution and by phenotypic stasis despite substantial levels of underlying molecular change. The phylogeny suggests that species diversification sometimes occurs by niche shifts, and sometimes occurs without a change in niche. Moreover, diversification in the Hyalella ecomorphs has involved the repeated evolution of similar phenotypic forms that exist in similar ecological settings, a hallmark of adaptive evolution. The evolutionary stasis observed in clades separated by substantial genetic divergence, but existing in similar habitats, is also suggestive of stabilizing natural selection acting to constrain phenotypic evolution within narrow bounds. We interpret the observed decoupling of genetic and phenotypic diversification in terms of adaptive radiation on an ecologically constrained adaptive landscape, and suggest that ecological constraints, perhaps acting together with genetic and functional constraints, may explain the parallel evolution and evolutionary stasis inferred by the phylogeny. [source] Differential expression of Bordetella pertussis iron transport system genes during infectionMOLECULAR MICROBIOLOGY, Issue 1 2008Timothy J. Brickman Summary Temporal expression patterns of the Bordetella pertussis alcaligin, enterobactin and haem iron acquisition systems were examined using alcA,, bfeA, and bhuR,tnpR recombinase fusion strains in a mouse respiratory infection model. The iron systems were differentially expressed in vivo, showing early induction of the alcaligin and enterobactin siderophore systems, and delayed induction of the haem system in a manner consistent with predicted changes in host iron source availability during infection. Previous mixed infection competition studies established the importance of alcaligin and haem utilization for B. pertussis in vivo growth and survival. In this study, the contribution of the enterobactin system to the fitness of B. pertussis was confirmed using wild-type and enterobactin receptor mutant strains in similar competition infection experiments. As a correlate to the in vivo expression studies of B. pertussis iron systems in mice, sera from uninfected and B. pertussis -infected human donors were screened for antibody reactivity with Bordetella iron-repressible cell envelope proteins. Pertussis patient sera recognized multiple iron-repressible proteins including the known outer membrane receptors for alcaligin, enterobactin and haem, supporting the hypothesis that B. pertussis is iron-starved and responds to the presence of diverse iron sources during natural infection. [source] Calluna vulgaris root cells show increased capacity for amino acid uptake when colonized with the mycorrhizal fungus Hymenoscyphus ericaeNEW PHYTOLOGIST, Issue 3 2002Sergei G. Sokolovski Summary ,,Ericoid mycorrhizas are believed to improve N nutrition of many ericaceous plant species that typically occur in habitats with impoverished nutrient status, by releasing amino acids from organic N forms. Despite the ubiquity of mycorrhizal formation the mechanisms and regulation of nutrient transport in mycorrhizal associations are poorly understood. ,,We used an electrophysiological approach to study how amino acid transport characteristics of Calluna vulgaris were affected by colonization with the ericoid mycorrhiza fungus Hymenoscyphus ericae . ,,Both the Vmax and Km parameters of amino acid uptake were affected by fungal colonization in a manner consistent with an increased availability of amino acid to the plant. ,,The ecophysiological significance of altered amino acid transport in colonized root cells of C. vulgaris is discussed. [source] Habitat-dependent foraging in a classic predator,prey system: a fable from snowshoe haresOIKOS, Issue 2 2005Douglas W. Morris Current research contrasting prey habitat use has documented, with virtual unanimity, habitat differences in predation risk. Relatively few studies have considered, either in theory or in practice, simultaneous patterns in prey density. Linear predator,prey models predict that prey habitat preferences should switch toward the safer habitat with increasing prey and predator densities. The density-dependent preference can be revealed by regression of prey density in safe habitat versus that in the riskier one (the isodar). But at this scale, the predation risk can be revealed only with simultaneous estimates of the number of predators, or with their experimental removal. Theories of optimal foraging demonstrate that we can measure predation risk by giving-up densities of resource in foraging patches. The foraging theory cannot yet predict the expected pattern as predator and prey populations covary. Both problems are solved by measuring isodars and giving-up densities in the same predator,prey system. I applied the two approaches to the classic predator,prey dynamics of snowshoe hares in northwestern Ontario, Canada. Hares occupied regenerating cutovers and adjacent mature-forest habitat equally, and in a manner consistent with density-dependent habitat selection. Independent measures of predation risk based on experimental, as well as natural, giving-up densities agreed generally with the equal preference between habitats revealed by the isodar. There was no apparent difference in predation risk between habitats despite obvious differences in physical structure. Complementary studies contrasting a pair of habitats with more extreme differences confirmed that hares do alter their giving-up densities when one habitat is clearly superior to another. The results are thereby consistent with theories of adaptive behaviour. But the results also demonstrate, when evaluating differences in habitat, that it is crucial to let the organisms we study define their own habitat preference. [source] Developmental plasticity in fat patterning of Ache children in response to variation in interbirth intervals: A preliminary test of the roles of external environment and maternal reproductive strategiesAMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 1 2009Jack Baker A firm link between small size at birth and later more centralized fat patterning has been established in previous research. Relationships between shortened interbirth intervals and small size at birth suggest that maternal energetic prioritization may be an important, but unexplored determinant of offspring fat patterning. Potential adaptive advantages to centralized fat storage (Baker et al., 2008: In: Trevathan W, McKenna J, Smith EO, editors. Evolutionary Medicine and Health: New Perspectives. New York: Oxford) suggest that relationships with interbirth intervals may reflect adaptive responses to variation in patterns of maternal reproductive effort. Kuzawa (2005: Am J Hum Biol 17:5,21; 2008: In: Trevathan W, McKenna J, Smith EO, editors. Evolutionary Medicine and Health: New Perspectives. New York: Oxford) has argued that maternal mediation of the energetic quality of the environment is a necessary component of developmental plasticity models invoking predictive adaptive responses (Gluckman and Hanson 2004: Trends Endocrinol Metab 15:183,187). This study tested the general hypothesis that shortened interbirth intervals would predict more centralized fat patterning in offspring. If long-term maternally mediated signals are important determinants of offspring responses, then we expected to observe a relationship between the average interbirth interval of mothers and offspring adiposity, with no relationship with the preceding interval. Such a finding would suggest that maternal, endogenous resource allocation decisions are related to offspring physiology in a manner consistent with Kuzawa's description. We observed exactly such a relationship among the Ache of Paraguay, suggesting that maternally mediated in utero signals of postnatal environments may be important determinants of later physiology. The implications of these findings are reviewed in light of life history and developmental plasticity theories and ourability to generalize the results to other populations. Recommendations for further empirical research are briefly summarized. Am. J. Hum. Biol., 2009. © 2008 Wiley-Liss, Inc. [source] Managerial complexity in project-based operations: A grounded model and its implications for practicePROJECT MANAGEMENT JOURNAL, Issue S1 2008Harvey Maylor Abstract This article reports an investigation into project managers' perceptions of managerial complexity. Based on a multistage empirical study, elements of "what makes a project complex to manage" were identified and classified under the dimensions of mission, organization, delivery, stakeholder, or team,the MODeST model. Further, the data showed that these elements had both structural and dynamic qualities and that the elements are interdependent. Project managers are shown to be embedded in this complexity. The practical implications of the research include the ability to describe managerial complexity in a manner consistent with the actuality of the lived project environment. This provides a framework for the description of the level of managerial challenge or difficulty, which will allow the assessment of individual and organizational responses to it in the future. Further, the opportunity exists for active management of complexity. [source] The effect of computer anxiety on price value trade-off in the on-line environmentPSYCHOLOGY & MARKETING, Issue 6 2003Rajneesh Suri This research adds to the understanding of how consumers' comfort with computers influences their evaluation of prices for goods offered over the Internet. The effect of computer anxiety, under different motivational conditions, on the evaluation of price for a product in an on-line environment was examined with the use of an experimental design. The results indicate that computer anxiety interacts with motivation to influence price perceptions, in a manner consistent with predictions derived from the process theories of attitude formation and change. Specifically, in the high-motivation condition, subjects with a greater level of computer anxiety viewed high price as indicative of higher value than those with less computer anxiety (who evaluated the low price as better value). In the low-motivation condition, both groups linked high price with higher perceived quality than the low price level. © 2003 Wiley Periodicals, Inc. [source] A scale for measuring store personalityPSYCHOLOGY & MARKETING, Issue 5 2003Alain d'Astous The objective of this research study was to develop a scale for measuring store personality and to assess its psychometric properties. A preliminary study showed that store personality comprised five dimensions, termed sophistication, solidity, genuineness, enthusiasm, and unpleasantness. A follow-up survey with 226 adult consumers confirmed the stability of the factorial structure of the 34-item store-personality scale as well as the reliability of each composite dimension. Some empirical evidence was gathered with respect to the scale's construct validity, because the proposed store-personality scale was shown to behave in a manner consistent with self-image congruence theory. Additional analyses revealed that a reduced scale including 20 items exhibited factorial stability and resulted in reliable measures of the five store-personality dimensions. Finally, some empirical support was obtained in favor of using the proposed scale across different retail settings. © 2003 Wiley Periodicals, Inc. [source] Promoting evidence-based psychosocial care for cancer patients,PSYCHO-ONCOLOGY, Issue 1 2009Paul B. Jacobsen Abstract With numerous studies demonstrating that psychosocial care reduces distress and improves quality of life, practitioners have an obligation to treat cancer patients in a manner consistent with this evidence. Although the rationale is straightforward, major challenges exist in achieving the goal of translating research into clinical practice. One challenge has been the nature of the evidence, with many studies of psychosocial interventions characterized by poor methodological quality, absence of eligibility criteria specifying heightened distress, and minimal consideration of dissemination potential. A second challenge has been to make practitioners aware of relevant evidence. Targeted efforts at dissemination, such as the issuance of clinical practice guidelines and evidence-based recommendations and the distribution of intervention materials via the Internet, appear to be more effective than passive efforts in providing practitioners with useful information. Perhaps the most challenging aspect has been to persuade practitioners to change how they practice. One approach currently under development would allow practitioners and health-care organizations to perform self-evaluations of the quality of their psychosocial care based on review of medical records. Feedback showing quality of care to be less than optimal is likely to motivate change, especially if the quality indicators assessed are considered to be important and reliable and point to specific actions that can be taken. The use of evidence to promote changes in clinical practice represents one of the major ways in which the field of psycho-oncology can fully realize its potential to positively affect the lives of people with cancer. Copyright © 2008 John Wiley & Sons, Ltd. [source] Voucher Privatization: A detour on the road to transition?THE ECONOMICS OF TRANSITION, Issue 3 2002Barbara G. Katz We explore an overlooked aspect of the design of the Czech voucher privatization programme, namely, the consequences of allowing individuals to distribute their vouchers among the voucher privatization funds (VPFs). We develop and analyse a model of voucher privatization in which we study the problem facing individuals who invest their vouchers in VPFs which, in turn, are able to use their skills to alter the performances of the firms in which they acquire shares. The VPFs have different skills and, by their bids and subsequent joint ownership patterns, affect the performances of the firms in their funds. We show that even in the case in which voucher holders have identical and full information, and wish to allocate their vouchers to the VPFs in a manner consistent with the maximization of economy,wide profit, a coordination failure generally prevents the implementation of this efficient outcome. Uncertainty, as well as differing payouts by the VPFs, is shown to exacerbate the problem. We conclude that there was an inherent flaw in the design of the Czech voucher scheme. JEL classification: D44, L33, P21, G11. [source] Comparison of ADHD symptom subtypes as source-specific syndromesTHE JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY AND ALLIED DISCIPLINES, Issue 6 2004Kenneth D. Gadow Background:, This study examines differences between the three subtypes of attention-deficit/hyperactivity disorder (ADHD), inattentive (I), hyperactive-impulsive (H), and combined (C), in a heterogeneous sample of 248 boys (ages 6 to 10 years) with emotional and behavioral problems who were recruited for participation in a diagnostic study. Method:, The boys and their mothers participated in an extensive evaluation that involved multiple assessments of cognitive, behavioral, academic, and family functioning. ADHD subtypes were defined on the basis of teacher alone, mother alone, and mother/teacher ratings of DSM-IV symptoms. Results:, Results indicated ADHD symptom groups showed a differential pattern of impairment socially (H,C>I) and cognitively (I,C>H). The C and H groups were the most and least impaired overall, respectively, and all subtypes were differentiated from the nonADHD clinical control or NONE (N) group in a manner consistent with the primary findings. External validation of group differences was limited, and there were marked inconsistencies in the pattern of findings depending on how groups were defined. For the most part, although the mother/teacher grouping strategy (compared with either alone) captured a greater diversity of differences between subtypes, it also obscured some. Conclusions:, Observed findings are consistent with the notion that mothers and teachers interpret symptom statements in terms of behaviors that are most relevant for their daily concerns. [source] Connections of eye-saccade-related areas within mesencephalic reticular formation with the optic tectum in goldfishTHE JOURNAL OF COMPARATIVE NEUROLOGY, Issue 1 2007Maria A. Luque Abstract Physiological studies demonstrate that separate sites within the mesencephalic reticular formation (MRF) can evoke eye saccades with different preferred directions. Furthermore, anatomical research suggests that a tectoreticulotectal circuit organized in accordance with the tectal eye movement map is present. However, whether the reticulotectal projection shifts with the gaze map present in the MRF is unknown. We explored this question in goldfish, by injecting biotin dextran amine within MRF sites that evoked upward, downward, oblique, and horizontal eye saccades. Then, we analyzed the labeling in the optic tectum. The main findings can be summarized as follows. 1) The MRF and the optic tectum were connected by separate axons of the tectobulbar tract. 2) The MRF was reciprocally connected mainly with the ipsilateral tectal lobe, but also with the contralateral one. 3) The MRF received projections chiefly from neurons located within intermediate and deep tectal layers. In addition, the MRF projections terminated primarily within the intermediate tectal layer. 4) The distribution of labeled neurons in the tectum shifted with the different MRF sites in a manner consistent with the tectal motor map. The area containing these cells was targeted by a high-density reticulotectal projection. In addition to this high-density topographic projection, there was a low-density one spread throughout the tectum. 5) Occasionally, boutons were observed adjacent to tectal labeled neurons. We conclude that the organization of the reticulotectal circuit is consistent with the functional topography of the MRF and that the MRF participates in a tectoreticulotectal feedback circuit. J. Comp. Neurol. 500:6,19, 2007. © 2006 Wiley-Liss, Inc. [source] | |||||||||||||||||||||||||