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Consistent Manner (consistent + manner)
Selected AbstractsApproaches for linking whole-body fish tissue residues of mercury or DDT to biological effects thresholdsENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 8 2005Nancy Beckvar Abstract A variety of methods have been used by numerous investigators attempting to link tissue concentrations with observed adverse biological effects. This paper is the first to evaluate in a systematic way different approaches for deriving protective (i.e., unlikely to have adverse effects) tissue residue-effect concentrations in fish using the same datasets. Guidelines for screening papers and a set of decision rules were formulated to provide guidance on selecting studies and obtaining data in a consistent manner. Paired no-effect (NER) and low-effect (LER) whole-body residue concentrations in fish were identified for mercury and DDT from the published literature. Four analytical approaches of increasing complexity were evaluated for deriving protective tissue residues. The four methods were: Simple ranking, empirical percentile, tissue threshold-effect level (t-TEL), and cumulative distribution function (CDF). The CDF approach did not yield reasonable tissue residue thresholds based on comparisons to synoptic control concentrations. Of the four methods evaluated, the t-TEL approach best represented the underlying data. A whole-body mercury t-TEL of 0.2 mg/kg wet weight, based largely on sublethal endpoints (growth, reproduction, development, behavior), was calculated to be protective of juvenile and adult fish. For DDT, protective whole-body concentrations of 0.6 mg/kg wet weight in juvenile and adult fish, and 0.7 mg/kg wet weight for early life-stage fish were calculated. However, these DDT concentrations are considered provisional for reasons discussed in this paper (e.g., paucity of sublethal studies). [source] A Behavioral Syndrome in the Adzuki Bean Beetle: Genetic Correlation Among Death Feigning, Activity, and Mating BehaviorETHOLOGY, Issue 2 2010Satoshi Nakayama When studying animal behavior, it is often necessary to examine traits as a package, rather than as isolated units. Evidence suggests that individuals behave in a consistent manner across different contexts or over time; that is, behavioral syndromes. We compared locomotor activity levels and mating success between beetles derived from two regimes artificially selected for the duration of death-feigning behavior in the adzuki bean beetle, Callosobruchus chinensis. The two selection regimes comprised strains with higher (L) and lower (S) intensity (frequency and duration) of death-feigning behavior, respectively. We found that S strains had higher activity levels than L strains for both sexes, i.e., there is a negative genetic correlation between death feigning and activity. In addition, we found that S strains had higher mating success than L strains, presumably due to higher activity, in males but not in females. We thus demonstrate that death feigning is genetically correlated to mating behavior in males but not females in this species, suggesting that behavioral correlations may not always reflect in the same way in both sexes. [source] Holding onto power: effects of powerholders' positional instability and expectancies on interactions with subordinatesEUROPEAN JOURNAL OF SOCIAL PSYCHOLOGY, Issue 4 2006John Georgesen This study explores the effects of power, positional threat, and expectancies on interactions between powerholders and subordinates. Two hundred and forty-two participants were randomly assigned to power role (boss or employee). Bosses were further randomly assigned to levels of positional threat (power role secure or insecure) and expectancy regarding subordinates' problem-solving ability (negative or positive). Evidence for a self-fulfilling prophecy was obtained, such that dyads where bosses held negative expectancies of their subordinates rated the subordinate and experience most negatively and awarded less potential prize money to the subordinates. Expectancy interacted with positional threat in a consistent manner such that the most negative effects were obtained for dyads where bosses were both positionally threatened and held negative expectancies of subordinates. Implications for theories of power are discussed. Copyright © 2006 John Wiley & Sons, Ltd. [source] Do arthropod assemblages display globally consistent responses to intensified agricultural land use and management?GLOBAL ECOLOGY, Issue 5 2008S. J. Attwood ABSTRACT Aim, To determine whether arthropod richness and abundance for combined taxa, feeding guilds and broad taxonomic groups respond in a globally consistent manner to a range of agricultural land-use and management intensification scenarios. Location, Mixed land-use agricultural landscapes, globally. Methods, We performed a series of meta-analyses using arthropod richness and abundance data derived from the published literature. Richness and abundance were compared among land uses that commonly occur in agricultural landscapes and that represent a gradient of increasing intensification. These included land-use comparisons, such as wooded native vegetation compared with improved pasture, and a management comparison, reduced-input cropping compared with conventional cropping. Data were analysed using three different meta-analytical techniques, including a simple vote counting method and a formal fixed-effects/random-effects meta-analysis. Results, Arthropod richness was significantly higher in areas of less intensive land use. The decline in arthropod richness was greater between native vegetation and agricultural land uses than among different agricultural land uses. These patterns were evident for all taxa combined, predators and decomposers, but not herbivorous taxa. Overall, arthropod abundance was greater in native vegetation than in agricultural lands and under reduced-input cropping compared with conventional cropping. Again, this trend was largely mirrored by predators and decomposers, but not herbivores. Main conclusions, The greater arthropod richness found in native vegetation relative to agricultural land types indicates that in production landscapes still containing considerable native vegetation, retention of that vegetation may well be the most effective method of conserving arthropod biodiversity. Conversely, in highly intensified agricultural landscapes with little remaining native vegetation, the employment of reduced-input crop management and the provision of relatively low-intensity agricultural land uses, such as pasture, may prove effective in maintaining arthropod diversity, and potentially in promoting functionally important groups such as predators and decomposers. [source] A new shear flexible cubic spline plate element for vibration analysisINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 11 2002B. P. Patel Abstract Here, a new cubic B-spline plate element is developed using field consistency principle, for vibration analysis. The formulation includes anisotropy, transverse shear deformation, in-plane and rotary inertia effects. The element is based on a laminated refined plate theory, which satisfies the interface transverse shear stress and displacement continuity, and has a vanishing shear stress on the top and bottom surfaces of the plates. The lack of consistency in the shear strain field interpolations in its constrained physical limits produces poor convergence and results in unacceptable solutions due to locking phenomenon. Hence, numerical experimentation for the evaluation of natural frequencies of plates is carried out to check this deficiency with a series of assumed shear strain functions, redistributed in a field consistent manner. Copyright © 2002 John Wiley & Sons, Ltd. [source] Toward a BSSE-free description of strongly interacting systemsINTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY, Issue 4 2002G.J. Halász Abstract The so-called "chemical Hamiltonian approach" (CHA) gives perfect a priori BSSE-free description of weak intermolecular interactions, but has been found inappropriate for describing strong interactions taking place within a molecule. Here, we propose a simple modification of the CHA/F BSSE-free SCF method, which retains all the good properties of the CHA/F method for the intermolecular case but can be used also to describe covalent and ionic interactions. This is vital for calculating whole potential surfaces of chemical reactions in a consistent manner, which was found impossible by using the a posteriori counterpoise correction method. Model calculations are presented for covalent and ionic chemical bonds and for a rare gas,proton system. © 2002 Wiley Periodicals, Inc. Int J Quantum Chem, 2002 [source] Using individual-based simulations to test the Levins metapopulation paradigmJOURNAL OF ANIMAL ECOLOGY, Issue 2 2002Matt J. Keeling Summary 1,Levins metapopulations have become a standard tool for modelling spatially heterogeneous populations. The acceptance of these models by ecologists may be attributed to their simple structure and their use of presence,absence data. 2,Using structured-metapopulations, which possess stochastic dynamics at the local subpopulation level, the extinction and subsequent recolonization rates can be calculated and compared to those of the classical Levins model. 3,Single-species metapopulations conform to the Levins ideal, validating the widespread use of this conceptual model. However, multispecies systems are shown to deviate in a consistent manner. This deviation, which is explained in terms of a correlation between patch occupancy and average population levels of the species, can be used to identify the signature of enemy,victim interactions. [source] Growth and the poor: a comment on Dollar and KraayJOURNAL OF INTERNATIONAL DEVELOPMENT, Issue 5 2002Malte Lübker In a recent paper Dollar and Kraay come to sweeping conclusions about economic growth and the poor. On the basis of empirical work they assert that standard World Bank and IMF policy packages are good for the poor. This paper demonstrates that (i) the empirical work is based on theoretically unsound equations; (ii) the data are seriously flawed; and (iii) the policy variables are not defined appropriately, nor are they tested in a consistent manner. These problems imply that the policy conclusions of the authors are unsafe. Copyright © 2002 John Wiley & Sons, Ltd. [source] An Assessment of the Terminology Used by Diplomates and Students to Describe the Character of Equine Mitral and Aortic Valve Regurgitant Murmurs: Correlations with the Physical Properties of the SoundsJOURNAL OF VETERINARY INTERNAL MEDICINE, Issue 3 2003Jonathan M. Naylor Twenty students and 16 diplomates listened to 7 recordings made from 7 horses with either aortic (n = 3) or mitral valve (n = 4) regurgitant murmurs. A total of 30 different terms were used to describe the character of these murmurs. However, only 4 terms were used in a repeatable and consistent manner. Most people described the character of a given mitral or aortic valve murmur with 1 or 2 terms. Diplomates drew from a pool of terms that was about half the size of that used by students,.1 ±2.0 terms for diplomats (mean ±1 SD) versus 13.1 ±1.8 terms for students (P < .001). Only blowing, honking, buzzing, and musical were markedly associated with the recording played. Frequency analysis of the murmurs allowed them to be classified as containing harmonics (n = 4) or not containing harmonics (n = 3). Blowing was used to describe murmurs without harmonics on 39 of 48 occasions and corresponds to the term noisy used in some older descriptions of equine murmurs. Honking, musical, and buzzing were markedly associated with murmurs that contained harmonics; these terms were used 23, 13, and 12 of a possible 64 times, respectively. The frequency of buzzing and honking murmurs (72.7 ±9.3 and 88.4 ±46.3 Hz, respectively) was markedly lower than that of musical murmurs (156.8 ±81.1 Hz) (all P values <.01). Honking murmurs (0.392 ±0.092 seconds) were shorter than those described as buzzing or musical (0.496 ±0.205 and 0.504 ±0.116 seconds, respectively). The data suggest that the terminology for the character of aortic and mitral regurgitant murmurs should be restricted to 4 terms: blowing, honking, buzzing, and musical. Honking, buzzing, and musical describe murmurs with a peak dominant frequency and harmonics; blowing describes murmurs without a peak frequency. Effective communication could be enhanced by playing examples of reference sounds when these terms are taught so that nomenclature is used more uniformly. Key words: Cardiac; Heart; Learning; Meaning. [source] A Partially Observed Model for Micromovement of Asset Prices with Bayes Estimation via FilteringMATHEMATICAL FINANCE, Issue 3 2003Yong Zeng A general micromovement model that describes transactional price behavior is proposed. The model ties the sample characteristics of micromovement and macromovement in a consistent manner. An important feature of the model is that it can be transformed to a filtering problem with counting process observations. Consequently, the complete information of price and trading time is captured and then utilized in Bayes estimation via filtering for the parameters. The filtering equations are derived. A theorem on the convergence of conditional expectation of the model is proved. A consistent recursive algorithm is constructed via the Markov chain approximation method to compute the approximate posterior and then the Bayes estimates. A simplified model and its recursive algorithm are presented in detail. Simulations show that the computed Bayes estimates converge to their true values. The algorithm is applied to one month of intraday transaction prices for Microsoft and the Bayes estimates are obtained. [source] Analysis of the effect of a mean velocity field on a mean field dynamoMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 4 2007Alejandra Kandus ABSTRACT We study semi-analytically and in a consistent manner the generation of a mean velocity field by helical magnetohydrodynamical (MHD) turbulence, and the effect that this field can have on a mean field dynamo. Assuming a prescribed, maximally helical small-scale velocity field, we show that large-scale flows can be generated in MHD turbulent flows via small-scale Lorentz force. These flows back-react on the mean electromotive force of a mean field dynamo through new terms, leaving the original , and , terms explicitly unmodified. Cross-helicity plays the key role in interconnecting all the effects. In the minimal , closure that we chose to work with, the effects are stronger for large relaxation times. [source] Intraoperative reported adverse events in childrenPEDIATRIC ANESTHESIA, Issue 8 2009ATHINA KAKAVOULI MD Summary Background:, Significant intraprocedural adverse events (AE) are reported in children who receive anesthesia for procedures outside the Operating Rooms (NORA). No study, so far, has characterized AE in children who receive anesthesia in the operating rooms (ORA) and NORA when anesthesia care is provided by the same team in a consistent manner. Objective/Aim:, We used the same patient-specific Quality Assurance questionnaires (QAs), to elucidate incidences of intraoperative reported AE for children receiving anesthesia in NORA and ORA locations. Through multivariate logistic regression analysis, we assessed the association between patient's AE risk and procedure's location while adjusting for American Society of Anesthesiologists (ASA) status, age, and unscheduled nature of the procedure. Methods/Materials:, After Institutional Review Board approval, we used returned QAs of patients under 21 years, who received anesthesia from our pediatric anesthesia faculty from May 1 2006 through September 30, 2007. We analyzed QA data on: service location, unscheduled/scheduled procedure, age, ASA status, presence, and type of AE. We excluded QAs with incomplete information on date, location, age, and ASA status. Results:, We included 8707 cases, with 3.5% incidence of reported AE. We had 1898 NORA and 6808 ORA cases with AE incidence of 2.5% and 3.7%, respectively. Multivariate regression analysis revealed that patients with higher ASA status or younger age had higher incidence of reported AE, irrespective of location or unscheduled nature of the procedure. The most common AE type, for both sites, was respiratory related (1.9%). Conclusions:, Pediatric reported AE incidence was comparable for NORA and ORA locations. Younger age or higher ASA status are associated with increased risk of AE. [source] A New Micromechanically Based Approach for the Elastic Response of Rubber,like Materials at Large StrainsPROCEEDINGS IN APPLIED MATHEMATICS & MECHANICS, Issue 1 2003Serdar Göktepe M. Sc. The approach models the elasticity of a rubber,like materials based on micro,structure that can be symbolized by a micro,sphere. The proposed model incorporates both non,a.ne deformation of unconstrained chains and superimposed constraint e.ects of tube,like topological formations in a consistent manner. Framework of the constitutive modeling and numerical examples illustrating the excellent predictive capacity of the model are presented. [source] The hydrodynamic and conformational properties of denatured proteins in dilute solutionsPROTEIN SCIENCE, Issue 1 2010Guy C. Berry Abstract Published data on the characterization of unfolded proteins in dilute solutions in aqueous guanidine hydrochloride are analyzed to show that the data are not fit by either the random flight or wormlike chain models for linear chains. The analysis includes data on the intrinsic viscosity, root-mean-square radius of gyration, from small-angle X-ray scattering, and hydrodynamic radius, from the translational diffusion coefficient. It is concluded that residual structure consistent with that deduced from nuclear magnetic resonance on these solutions can explain the dilute solution results in a consistent manner through the presence of ring structures, which otherwise have an essentially flexible coil conformation. The ring structures could be in a state of continual flux and rearrangement. Calculation of the radius of gyration for the random-flight model gives a similar reduction of this measure for chains joined at their endpoints, or those containing loop with two dangling ends, each one-fourth the total length of the chain. This relative insensitivity to the details of the ring structure is taken to support the behavior observed across a range of proteins. [source] A review on the use of the adjoint method in four-dimensional atmospheric-chemistry data assimilationTHE QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Issue 576 2001K.-Y. Wang Abstract In this paper we review a theoretical formulation of the adjoint method to be used in four-dimensional (4D) chemistry data assimilation. The goal of the chemistry data assimilation is to combine an atmospheric-chemistry model and actual observations to produce the best estimate of the chemistry of the atmosphere. The observational dataset collected during the past decades is an unprecedented expansion of our knowledge of the atmosphere. The exploitation of these data is the best way to advance our understanding of atmospheric chemistry, and to develop chemistry models for chemistry-climate prediction. The assimilation focuses on estimating the state of the chemistry in a chemically and dynamically consistent manner (if the model allows online interactions between chemistry and dynamics). In so doing, we can: produce simultaneous and chemically consistent estimates of all species (including model parameters), observed and unobserved; fill in data voids; test the photochemical theories used in the chemistry models. In this paper, the Hilbert space is first formulated from the geometric structure of the Banach space, followed by the development of the adjoint operator in Hilbert space. The principle of the adjoint method is described, followed by two examples which show the relationship of the gradient of the cost function with respect to the output vector and the gradient of the cost function with respect to the input vector. Applications to chemistry data assimilation are presented for both continuous and discrete cases. The 4D data variational adjoint method is then tested in the assimilation of stratospheric chemistry using a simple catalytic ozone-destruction mechanism, and the test results indicate that the performance of the assimilation method is good. [source] Correlative analysis of gene expression profile and prognosis in patients with gliomatosis cerebriCANCER, Issue 16 2009Oscar Fernando D'Urso PhD Abstract BACKGROUND: In modern clinical neuro-oncology, the pathologic diagnoses are very challenging, creating significant clinical confusion and affecting therapeutic decisions and prognosis. METHODS: TP53 and PTEN gene sequences were analyzed, and microarray expression profiling was also performed. The authors investigated whether gene expression profiling, coupled with class prediction methodology, could be used to determine the prognosis of gliomatosis cerebri in a more consistent manner than standard pathology. RESULTS: The authors reported the results of a molecular study in 59 cases of gliomatosis cerebri, correlating these results with prognosis. The well-known prognostic factors of gliomas (ie, age, Karnofsky performance status, histology [grade 2 vs 3], and contrast enhancement) were found to be predictive of response or outcome in only a percentage of patients but not in all patients. The authors identified a 23-gene signature that was able to predict patient prognosis with microarray gene expression profiling. With the aim of producing a prognosis tool that is useful in clinical investigation, the authors studied the expression of this 23-gene signature by real-time quantitative polymerase chain reaction. Real-time expression values relative to these 23 gene features were used to build a prediction method able to distinguish patients with a good prognosis (those more likely to be responsive to therapy) from patients with a poor prognosis (those less likely to be responsive to therapy). CONCLUSIONS: The results of the current study demonstrated not only a strong association between gene expression patterns and patient survival, but also a robust replicability of these gene expression,based predictors. Cancer 2009. © 2009 American Cancer Society. [source] Fuzzy automata and lifeCOMPLEXITY, Issue 3 2002Clifford A. Reiter Abstract Boolean cellular automata may be generalized to fuzzy automata in a consistent manner. Several fuzzy logics are used to create 1-dimensional automata and also 2-dimensional automata that generalize the game of life. These generalized automata are investigated and compared to their Boolean counterparts empirically and using rule entropy and repeated input response functions. Fuzzy automata offer new mechanisms for classification of classical automata and can be used for insight into their qualitative behavior. © 2002 Wiley Periodicals, Inc. [source] | |||||||||||||||||||