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Functional Approach (functional + approach)

Distribution by Scientific Domains

Life Sciences	32%
Medical Sciences	20%
Engineering	20%
Chemistry	7%
Psychology	5%
Polymers and Materials Science	5%
3 Other Domains	11%

Kinds of Functional Approach

density functional approach

Selected Abstracts

Efficient Simulations of Charged Colloidal Dispersions: A Density Functional Approach

MACROMOLECULAR THEORY AND SIMULATIONS, Issue 4 2005
Kang Kim
Abstract Summary: A numerical method is presented for simulating charged colloidal dispersions in electrolyte solutions. Utilizing a smoothed profile for colloid-solvent boundaries, efficient mesoscopic simulations are enabled for modeling dispersions of many colloidal particles exhibiting many-body electrostatic interactions. The validity of the method was examined for simple colloid geometries, and the efficiency was demonstrated by calculating stable structures of two-dimensional dispersions, which resulted in the formation of colloidal crystals. Formation of a charged colloidal crystal. [source]

Integrating Formal and Functional Approaches to Language Teaching in French Immersion: An Experimental Study

LANGUAGE LEARNING, Issue 2001
Elaine M. Day
This experimental study was designed to evaluate the effect on French language proficiency of an integrated formal, analytic and functional, communicative approach (experiential) to second-language teaching in the immersion classroom. The impetus for the study arises from previous research indicating that immersion children show persistent weaknesses in their grammatical skills despite the fluent, functional proficiency they achieve in their second language. The experimental materials, which were custom-designed for our study, highlight form-function relations, promote noticing, encourage metalin-guistic awareness, and provide opportunities for language practice and thus relate to some of the theoretical issues that Rod Ellis (this volume) has indicated are important in SLA in the 90s. This classroom-based study on the conditional is one of a series of studies undertaken in Canadian French immersion to investigate the effectiveness of form-focused instruction in classrooms (see Swain, 2000). The results of our study, which was conducted in grade 7 early immersion, showed that the Experimental group performed significantly higher in writing than the Control group, in both the post- and the follow-up testing. Although this was not found for speaking, an examination of the individual class data revealed greater and more consistent growth in speaking for the Experimental than for the Control classes, suggesting that they benefited somewhat from the experi- mental treatment in this domain as well. Although Ellis (this volume) notes that research on form-focused instruc- tion in the 90s has tended to split pedagogy from theory, the immersion research in this area does not seem t o reflect this shift. In a recent article, Swain (2000) reviews the French Immersion (FI) studies and summarizes their re- sults as follows: "Overall, the set of experiments conducted in FI classes suggest that there is value in focusing on language form through the use of pre-planned curriculum materials in the context of content-based language learn- ing" (Swain, 2000, p. 205). Her reference to curriculum materials and to the specific context of content-based lan- guage learning should signal to the reader the orientation t o pedagogical considerations that characterize this research. As Ellis notes, hybrid research using both experimental and qualitative methods is becoming more common in SLA. Recently, the experimental materials in our study were implemented in a grade 8 immersion classroom, and the children's collaborative language activity was observed by a researcher working from a sociocultural theoretical per- spective (Spielman-Davidson, 2000). The uptake of our research by a researcher working in another paradigm introduces another kind of hybridity that we hope will also shed further light on questions in form-focused instruction and lead to appropriate changes in pedagogy and in the design of immersion curricula. [source]

Functional approach to investigate Lp(a) in ischaemic heart and cerebral diseases

EUROPEAN JOURNAL OF CLINICAL INVESTIGATION, Issue 2 2003
A. De La Peña-Díaz
Abstract Background Lp(a), a major cardiovascular risk factor, contains a specific apolipoprotein, apo(a), which by virtue of structural homology with plasminogen inhibits the formation of plasmin, the fibrinolytic enzyme. A number of clinical reports support the role of Lp(a) as a cardiovascular or cerebral risk factor, and experimental data suggest that it may contribute to atherothrombosis by inhibiting fibrinolysis. Design A well-characterized model of a fibrin surface and an apo(a)-specific monoclonal antibody were used to develop a functional approach to detect pathogenic Lp(a). The assay is based on the competitive binding of Lp(a) and plasminogen for fibrin, and quantifies fibrin-bound Lp(a). High Lp(a) binding to fibrin is correlated with decreased plasmin formation. In a transversal case,control study we studied 248 individuals: 105 had a history of ischaemic cardiopathy (IC), 52 had cerebro-vascular disease (CVD) of thrombotic origin, and 91 were controls. Results The remarkably high apo(a) fibrin-binding in CVD (0·268 ± 0·15 nmol L,1) compared with IC (0·155 ± 0·12 nmol L,1) suggests the existence of peculiar and poorly understood differences in pro- or anti-thrombotic mechanisms in either cerebral and/or coronary arteries. Conclusions Our results demonstrated that Lp(a) fibrin-binding and small Apo(a) isoforms are associated with athero-thrombotic disease. [source]

Morphological and physiological sexual selection targets in a territorial damselfly

ECOLOGICAL ENTOMOLOGY, Issue 6 2009
INE SWILLEN
Abstract. 1Several morphological and physiological traits may shape fitness through the same performance measure. In such cases, differentiating between a scenario of many-to-one mapping, where phenotypic traits independently shape fitness leading to functional redundancy, and a scenario where traits strongly covary among each other and fitness, is needed. 2A multivariate approach was used, including morphological and physiological traits related to flight ability, a crucial performance measure in flying insects, to identify independent correlates of short-term mating success (mated versus unmated males) in the territorial damselfly Lestes viridis. 3Males with higher flight muscle mass, higher relative thorax mass, and more symmetrical hindwings, all traits presumably linked to manoeuvrability, were more likely to be mated. Unexpectedly, although relative thorax mass is often used as a proxy for flight muscle mass, both traits were selected for independently. Mated males had a higher thorax fat content than unmated males, possibly because of enhanced flight endurance. 4The finding of several independent targets of sexual selection linked to flight ability is consistent with a scenario of many-to-one mapping between phenotype and performance. Identifying such a scenario is important, because it may clarify situations where animals may show suboptimal values for some phenotypic traits shaping a performance measure, while still having high performance and fitness. We argue in the discussion that the functional approach of sexual selection provides a potent tool for examining unresolved issues in both sexual selection theory, as well as life-history theory. [source]

Functional approach to investigate Lp(a) in ischaemic heart and cerebral diseases

Trellis coded quantization/trellis coded continuous phase modulation over Rician channel with imperfect phase reference

EUROPEAN TRANSACTIONS ON TELECOMMUNICATIONS, Issue 5 2004
Osman Nuri Ucan
In this paper, to improve bandwidth efficiency and error performance, trellis coded quantization/trellis continuous phase modulation (TCQ/TCPM) are combined and a trellis coded quantization/trellis coded continuous phase modulation (TCQ/TCCPM) scheme is introduced. Here, we use TCQ/TCM system as source coding because of its advantage over classical joint systems in terms of decoding time and complexity. We also present CPM for TCQ/TCM signals, since CPM provides low spectral occupancy and is suitable for power and bandwidth limited channels. The bit error performance of TCQ/TCCPM schemes is derived taking into account quantization noise over Rician channel with imperfect phase reference. The analytical upper bounds are obtained using Chernoff bounding technique, combined with the modified generating functional approach with no channel state information (CSI) and no side information for the phase noise process. As an example, TCQ/TCCPM scheme for 16CPFSK with modulation index h,=,1/2 (16CPFSK-TCQ/TCCPM) is investigated and compared to TCQ/TCM for 16PSK (16PSK-TCQ/TCM). It is shown that 16CPFSK-TCQ/TCCPM has better bit error performance than 16PSK-TCQ/TCM in all signal-to-noise-ratio (SNR) and quantization noise effect increases at high SNR values for both uniform and optimum quantization. Copyright © 2004 AEI. [source]

PEAK SHIFT DISCRIMINATION LEARNING AS A MECHANISM OF SIGNAL EVOLUTION

EVOLUTION, Issue 6 2005
Spencer K. Lynn
Abstract "Peak shift" is a behavioral response bias arising from discrimination learning in which animals display a directional, but limited, preference for or avoidance of unusual stimuli. Its hypothesized evolutionary relevance has been primarily in the realm of aposematic coloration and limited sexual dimorphism. Here, we develop a novel functional approach to peak shift, based on signal detection theory, which characterizes the response bias as arising from uncertainty about stimulus appearance, frequency, and quality. This approach allows the influence of peak shift to be generalized to the evolution of signals in a variety of domains and sensory modalities. The approach is illustrated with a bumblebee (Bombus impatiens) discrimination learning experiment. Bees exhibited peak shift while foraging in an artificial Batesian mimicry system. Changes in flower abundance, color distribution, and visitation reward induced bees to preferentially visit novel flower colors that reduced the risk of flower-type misidentification. Under conditions of signal uncertainty, peak shift results in visitation to rarer, but more easily distinguished, morphological variants of rewarding species in preference to their average morphology. Peak shift is a common and taxonomically widespread phenomenon. This example of the possible role of peak shift in signal evolution can be generalized to other systems in which a signal receiver learns to make choices in situations in which signal variation is linked to the sender's reproductive success. [source]

An integrative approach identifies developmental sequence heterochronies in freshwater basommatophoran snails

EVOLUTION AND DEVELOPMENT, Issue 2 2007
Jennifer J. Smirthwaite
SUMMARY Adopting an integrative approach to the study of sequence heterochrony, we compared the timing of developmental events encompassing a mixture of developmental stages and functional traits in the embryos of 12 species of basommatophoran snails in an explicit phylogenetic framework. PARSIMOV analysis demonstrated clear functional heterochronies associated both with basal branches within the phylogeny and with terminal speciation events. A consensus of changes inferred under both accelerated transformation and delayed transformation optimizations identified four heterochronies where the direction of movement was known plus six twin heterochronies where the relative movements of the two events could not be assigned. On average, 0.5 and 0.58 events were inferred to have changed their position in the developmental sequence on internal and terminal branches of the phylogeny, respectively; these values are comparable with frequencies of sequence heterochrony reported in mammals. Directional heterochronies such as the early occurrence of body flexing in relation to the ontogeny of the eye spots, heart beat, and free swimming events occurred convergently and/or at different levels (i.e., familial, generic, and species) within the phylogeny. Such a functional approach to the study of developmental sequences has highlighted the possibility that heterochrony may have played a prominent role in the evolution of this group of invertebrates. [source]

The graviton propagator with a non-conserved external generating source

FORTSCHRITTE DER PHYSIK/PROGRESS OF PHYSICS, Issue 11-12 2007
E.B. Manoukian
Abstract A novel general expression is obtained for the graviton propagator from Lagrangian field theory by taking into account the necessary fact that in the functional differential approach of quantum field theory, in order to generate non-linearities in gravitation and interactions with matter, the external source T,,, coupled to the gravitational field, should a priori not be conserved ,,T,,, 0, so variations with respect to its ten components may be varied independently. The resulting propagator is the one which arises in the functional approach and does not coincide with the corresponding time-ordered product of two fields and it includes so-called Schwinger terms. The quantization is carried out in a gauge corresponding to physical states with two polarization states to ensure positivity in quantum applications. [source]

A functional approach to sexual selection

FUNCTIONAL ECOLOGY, Issue 4 2007
DUNCAN J. IRSCHICK
Summary 1Sexual selection theory is a robust and dynamic field within evolutionary biology, yet despite decades of research, remarkably little is known of the mechanistic bases of mate choice and male competition. 2Because many aspects of sexual selection involve dynamic movements, and are physically challenging, the limits of sexual selection may be defined by key functional and physiological variables (i.e. the ,functional approach'). 3We advocate the functional approach for providing mechanistic resolution on the adaptive basis of sexual structures and signals, the nature of mate choice and how males compete, among other issues. 4An overview of recent work, highlighted in this special issue, shows that many features of sexual selection, including the outcome of male fights, the morphology and design of sexual signals, and the nature of mate choice, all appear to be dictated in large part by functional and physiological parameters. 5We argue that the functional approach provides a potent tool for resolving several unresolved issues in sexual selection theory, particularly the nature of male quality, the handicap and indicator models of sexual selection, and the basis of mate choice. [source]

Exploitation of High-Yields in Hard-Rock Aquifers: Downscaling Methodology Combining GIS and Multicriteria Analysis to Delineate Field Prospecting Zones

GROUND WATER, Issue 4 2001
Patrick Lachassagne
Based on research work in the Truyàre River catchment of the Massif Central (Lozàre Department, France), a methodology has been developed for delineating favorable prospecting zones of a few square kilometers within basement areas of several hundred, if not thousand, square kilometers for the purpose of siting high-yield water wells. The methodology adopts a functional approach to hard-rock aquifers using a conceptual model of the aquifer structure and of the functioning of the main aquifer compartments: the alterites (weathered and decayed rock), the underlying weathered-fissured zone, and the fractured bedrock. It involves an economically feasible method of mapping the thickness and spatial distribution of the alterites and the weathered-fissured zone, on which the long-term exploitation of the water resource chiefly depends. This method is used for the first time in hydrogeology. The potential ground water resources were mapped by GIS multicriteria analysis using parameters characterizing the structure and functioning of the aquifer, i.e., lithology and hydrogeological properties of the substratum, nature and thickness of the alterites and weathered-fissured zone, depth of the water table, slope, fracture networks and present-day tectonic stresses, and forecasted ground water quality. The methodology involves a coherent process of downscaling that, through applying methods that are increasingly precise but also increasingly costly, enables the selection of sites with diminishing surface areas as the work advances. The resulting documents are used for ground water exploration, although they can also be applied to the broader domain of land-use management. [source]

Optimal flow control for Navier,Stokes equations: drag minimization

INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS, Issue 4 2007
L. Dedè
Abstract Optimal control and shape optimization techniques have an increasing role in Fluid Dynamics problems governed by partial differential equations (PDEs). In this paper, we consider the problem of drag minimization for a body in relative motion in a fluid by controlling the velocity through the body boundary. With this aim, we handle with an optimal control approach applied to the steady incompressible Navier,Stokes equations. We use the Lagrangian functional approach and we consider the Lagrangian multiplier method for the treatment of the Dirichlet boundary conditions, which include the control function itself. Moreover, we express the drag coefficient, which is the functional to be minimized, through the variational form of the Navier,Stokes equations. In this way, we can derive, in a straightforward manner, the adjoint and sensitivity equations associated with the optimal control problem, even in the presence of Dirichlet control functions. The problem is solved numerically by an iterative optimization procedure applied to state and adjoint PDEs which we approximate by the finite element method. Copyright © 2007 John Wiley & Sons, Ltd. [source]

Solvent effect on the reactivity of CIS -platinum (II) complexes: A density functional approach

INTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY, Issue 8 2008
Pubalee Sarmah
Abstract The structure and chemical reactivity of some selected cis -platinum(II) complexes, including clinically used drug molecules, cisplatin, carboplatin, and oxaliplatin are investigated using density functional theory (DFT) calculations. Calculated geometries of the complexes are in agreement with their available X-ray data. The global and local reactivity descriptors, such as hardness, chemical potential, electrophilicity index, Fukui function, and local philicity are calculated to investigate the usefulness of these descriptors for understanding the reactive nature and reactive sites of the complexes. Inclusion of solvent effect shows that both global and local descriptors change the trend of reactivity with respect to their trend in the gas phase. The stability of the complexes increases with the inclusion of water molecules. Simple regression analysis is applied to build up a quantitative structure-activity relationship (QSAR) model based on DFT derived electrophilicity index for the Pt(II) complexes against A2780 human ovarian adenocarcinoma cell line to establish the importance of the descriptor in predicting cytotoxicity. © 2008 Wiley Periodicals, Inc. Int J Quantum Chem, 2008 [source]

Endohedral carbon chains in chiral single-wall carbon nanotubes

INTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY, Issue 11 2006
Ravi K. Vadapalli
Abstract Using a first-principles, local density functional approach, we report the bond length optimization of endohedral linear carbon chains. In these calculations, all-carbon nanowire structures were constructed by inserting cumulenic linear carbon chains inside the semiconducting (7,3) and metallic (7,4) single-wall carbon nanotubes with radii of ,0.35 nm. Our calculations show that the total energy results for the endohedral chains inside both (7,3) and (7,4) nanotubes are well described with a common total energy curve having an equilibrium bond length of ,0.129 nm. The electronic band structures of the carbon nanowires are described in terms of a rigid-band model, with the Fermi level for the carbon nanowire effectively pinned near the top of bands originating from the valence band of the single-wall nanotube. © 2006 Wiley Periodicals, Inc. Int J Quantum Chem, 2006 [source]

Antimicrobial finishing of regular and modified nylon-6 fabrics

JOURNAL OF APPLIED POLYMER SCIENCE, Issue 2 2008
S. E. Shalaby
Abstract A simple, efficient, and practically applicable functional approach for improvement antimicrobial properties of nylon-6 fabrics and increase the washing durability of biofunctions was developed. This finishing approach is based on grafting of the fabrics with methacrylic acid (MAA) to create additional carboxylic groups in nylon-6 macromolecules, followed by subsequent reaction with dimethylalklbenzyl ammonium chloride (DMABAC) solution under alkaline conditions. The carboxylic groups react with cationic agent through ionic interaction, which led to the immobilization of QAS on nylon-6 fabrics. This immobilization was proofed through determination of nitrogen content, applying scanning electron microscopy (SEM), and FTIR microscopy. The effect of treatment conditions on salt uptake (SUT) on nylon-6 fabrics and reaction efficiency (RE) was investigated. The antimicrobial assessment of regular and grafted with PMAA nylon-6 fabrics treated with DMABAC revealed that both types of fabrics are characterized before washing, by quite strong biocide effect on Bacillus mycoides, Escherichia coli and Candida albicans. The role of grafting nylon-6 fabrics before treatment with salt on durability of antimicrobial functions seems to be more significant as the samples were repeatedly washed. Even after Laundring 10 times the grafted samples could still provide 80%, 100%, and 87.5% microbial reduction against B. mycoides, E. coli and C. albicans, respectively, in contrast with 42.6%, 65.6%, and 42.5% in case of regular nylon-6 fabrics. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008. [source]

Bone Mineral Content per Muscle Cross-Sectional Area as an Index of the Functional Muscle-Bone Unit,

JOURNAL OF BONE AND MINERAL RESEARCH, Issue 6 2002
Eckhard Schoenau M.D.
Abstract Bone densitometric data often are difficult to interpret in children and adolescents because of large inter- and intraindividual variations in bone size. Here, we propose a functional approach to bone densitometry that addresses two questions: Is bone strength normally adapted to the largest physiological loads, that is, muscle force? Is muscle force adequate for body size? To implement this approach, forearm muscle cross-sectional area (CSA) and bone mineral content (BMC) of the radial diaphysis were measured in 349 healthy subjects from 6 to 19 years of age (183 girls), using peripheral quantitative computed tomography (pQCT). Reference data were established for height-dependent muscle CSA and for the variation with age in the BMC/muscle CSA ratio. These reference data were used to evaluate results from three pediatric patient groups: children who had sustained multiple fractures without adequate trauma (n = 11), children with preterminal chronic renal failure (n = 11), and renal transplant recipients (n = 15). In all three groups mean height, muscle CSA, and BMC were low for age, but muscle CSA was normal for height. In the multiple fracture group and in renal transplant recipients the BMC/muscle CSA ratio was decreased (p < 0.05), suggesting that bone strength was not adapted adequately to muscle force. In contrast, chronic renal failure patients had a normal BMC/muscle CSA ratio, suggesting that their musculoskeletal system was adapted normally to their (decreased) body size. This functional approach to pediatric bone densitometric data should be adaptable to a variety of densitometric techniques. [source]

Alcohol-related violence defined by ultimate goals: a qualitative analysis of the features of three different types of violence by intoxicated young male offenders

AGGRESSIVE BEHAVIOR, Issue 1 2010
Mary McMurran
Abstract Based upon a functional approach to understanding aggression, we aimed to identify the occurrence of and to describe the features of three types of alcohol-related violence defined a priori by ultimate goals: (1) violence in pursuit of nonsocial profit-based goals, (2) violence in pursuit of social dominance goals, and (3) violence as defence in response to threat. A sample of 149 young men with offences of violence that were alcohol related was interviewed. Cases were classified and detailed information from the first ten cases in each class (N=30) was subjected to thematic analysis. Intoxicated violence in pursuit of nonsocial profit-based goals was opportunistic and motivated by the desire for more alcohol or drugs. Violence, in these cases, although serious, appeared to be brief. Intoxicated violence in pursuit of social dominance goals was typically precipitated by past or current insult or injury, and was accompanied by strong anger and an adrenaline rush. Attacks were ferocious, and robbing the victim was not uncommon, perhaps to inflict additional humiliation. Feelings of pride and satisfaction were typical and expressions of remorse were uncommon. Regarding intoxicated violence as defence in response to threat, attacks were often expected, and in some cases the respondent made a pre-emptive strike. Weapon use was common in this group. Fear was experienced, but so too was anger. Feelings of excitement were not reported and remorse was common. Further validation of these types is warranted, and the potential implications of these findings for prevention and treatment are discussed. Aggr. Behav. 36:67,79, 2010. © 2009 Wiley-Liss, Inc. [source]

Expectancy and Risk for Alcoholism: The Unfortunate Exploitation of a Fundamental Characteristic of Neurobehavioral Adaptation

ALCOHOLISM, Issue 5 2002
Mark S. Goldman
Psychological investigations of alcohol expectancies over the last 20 years, using primarily verbal techniques, have strongly supported expectancies as an important mediator of biological and environmental antecedent variables that influence risk for alcohol use and abuse. At the same time, rapid developments in neuroscience, cognitive science, affective science, computer science, and genetics proved to be compatible with the concept of expectancy and, in some cases, used this concept directly. By using four principles that bear on the integration of knowledge in the biological and behavioral sciences,consilience, conservation, contingency, and emergence,these developments are merged into an integrated explanation of alcoholism and other addictions. In this framework, expectancy is seen as a functional approach to adaptation and survival that has been manifested in multiple biological systems with different structures and processes. Understood in this context, addiction is not a unique behavioral problem or special pathology distinct from the neurobehavioral substrate that governs all behavior, but is rather a natural (albeit unfortunate) consequence of these same processes. The ultimate intent is to weave a working heuristic that ties together findings from molecular and molar levels of inquiry and thereby might help direct future research. Such integration is critical in the multifaceted study of addictions. [source]

Comparison of two plant functional approaches to evaluate natural restoration along an old-field , deciduous forest chronosequence

JOURNAL OF VEGETATION SCIENCE, Issue 2 2009
Isabelle Aubin
Abstract Question: Are direct and indirect trait-based approaches similar in their usefulness to synthesize species responses to successional stages? Location: Northern hardwood forests, Québec, Canada (45°01,,45°08,N; 73°58,,74°21,W). Methods: Two different trait-based approaches were used to relate plant functional traits to succession on an old-field , deciduous forest chronosequence: (i) a frequently used approach based on co-occurrence of traits (emergent groups), and (ii) a new version of a direct functional approach at the trait level (the fourth-corner method). Additionally, we selected two different cut-off levels for the herb subset of the emergent group classification in order to test its robustness and ecological relevance. Results: Clear patterns of trait associations with stand developmental stages emerged from both the emergent group and the direct approach at the trait level. However, the emergent group classification was found to hide some trait-level differences such as a shift in seed size, light requirement and plant form along the chronosequence. Contrasting results were obtained for the seven or nine group classification of the herbaceous subset, illustrating how critical is the number of groups for emergent group classification. Conclusion: The simultaneous use of two different trait-based approaches provided a robust and comprehensive characterization of vegetation responses in the old-field , deciduous forest chronosequence. It also underlines the different goals as well as the limitations and benefits of these two approaches. Both approaches indicated that abandoned pastures of the northern hardwood biome have good potential for natural recovery. Conversion of these lands to other functions may lead to irremediable loss of biodiversity. [source]

The packaging technology and science of ancient transport amphoras,

PACKAGING TECHNOLOGY AND SCIENCE, Issue 4 2002
Diana Twede
Abstract Commercial transport amphoras are large ceramic vessels that were used from 1500 BC to 500 AD to ship wine and other products throughout the Mediterranean. The most large-scale use was to serve the ancient Greek and Roman empires. Although their form is much different from our own packages, the shape and design were clearly the result of the same reasoning that we use to design successful packaging today. They were designed to be economical to produce and ship. The unusual shapes, and especially the pointed base, facilitated handling, storage, transport and use in logistical systems that were very differently shaped from those that we use today. This paper investigates amphoras as a packaging system from a functional approach. It describes their protective physical properties, manufacturing process and industry structure, logistical and marketing advantages, and illustrates the value of such packaging artifacts in documenting the history of trade. Copyright © 2002 John Wiley & Sons, Ltd. [source]

Religion, spirituality, and genetics: Mapping the terrain for research purposes,

AMERICAN JOURNAL OF MEDICAL GENETICS, Issue 1 2009
Larry R. Churchill
Abstract Genetic diseases often raise issues of profound importance for human self-understanding, such as one's identity, the family or community to which one belongs, and one's future or destiny. These deeper questions have commonly been seen as the purview of religion and spirituality. This essay explores how religion and spirituality are understood in the current US context and defined in the scholarly literature over the past 100 years. It is argued that a pragmatic, functional approach to religion and spirituality is important to understanding how patients respond to genetic diagnoses and participate in genetic therapies. A pragmatic, functional approach requires broadening the inquiry to include anything that provides a framework of transcendent meaning for the fundamental existential questions of human life. This approach also entails suspending questions about the truth claims of any particular religious/spiritual belief or practice. Three implications of adopting this broad working definition will be presented. © 2009 Wiley-Liss, Inc. [source]

Baddeley revisited: The functional approach to autobiographical memory

APPLIED COGNITIVE PSYCHOLOGY, Issue 8 2009
Susan Bluck
In Baddeley's (1988) classic article he challenged researchers to take a functional approach by asking, for their phenomenon of interest, "but what the hell is it for?" In twenty years, how far has the field advanced in addressing this question, particularly in examining the functions of autobiographical memory? This introductory article provides an overview of the functional approach. Next, eight core articles appear, each framed to address Baddeley's question. The core articles are written by experts on distinct empirically established autobiographical memory phenomena: each presents a synopsis of current research in their area and then examines the function that their specific autobiographical memory phenomenon serves in human activity and adaptation. The issue ends with two commentaries by scholars who provide analyses of the functional approach from unique perspectives. Revisiting Baddeley provides an opportunity for a current discussion of the strengths and challenges of taking a functional approach to autobiographical memory. Copyright © 2009 John Wiley & Sons, Ltd. [source]

NETWORK-INDUCED DELAY-DEPENDENT H, CONTROLLER DESIGN FOR A CLASS OF NETWORKED CONTROL SYSTEMS

ASIAN JOURNAL OF CONTROL, Issue 2 2006
Xiefu Jiang
ABSTRACT This paper is concerned with the problem of robust H, controller design for a class of uncertain networked control systems (NCSs). The network-induced delay is of an interval-like time-varying type integer, which means that both lower and upper bounds for such a kind of delay are available. The parameter uncertainties are assumed to be normbounded and possibly time-varying. Based on Lyapunov-Krasovskii functional approach, a robust H, controller for uncertain NCSs is designed by using a sum inequality which is first introduced and plays an important role in deriving the controller. A delay-dependent condition for the existence of a state feedback controller, which ensures internal asymptotic stability and a prescribed H, performance level of the closed-loop system for all admissible uncertainties, is proposed in terms of a nonlinear matrix inequality which can be solved by a linearization algorithm, and no parameters need to be adjusted. A numerical example about a balancing problem of an inverted pendulum on a cart is given to show the effectiveness of the proposed design method. [source]

Stochastic Stability and H, Disturbance Attenuation of A Class of Nonlinear Stochastic Delayed Systems

ASIAN JOURNAL OF CONTROL, Issue 4 2001
Yong-Yan Cao
ABSTRACT In this paper, we consider stochastic stability analysis and H, disturbance attenuation for a class of discrete-time nonlinear stochastic retarded systems whose nonlinearities are described by statistical means. First a sufficient condition on mean square stability, which is independent of delay, is proposed using the stochastic Lyapunov functional approach. Then, H, disturbance attenuation property of the system is analyzed. It is shown that the H, disturbance attenuation of such nonlinear systems can be reduced to a linear matrix inequality problem. [source]

Personal exposure to mobile communication networks and well-being in children,A statistical analysis based on a functional approach

BIOELECTROMAGNETICS, Issue 4 2009
Anja Kühnlein
Abstract The MobilEe-study was the first cross-sectional population-based study to investigate possible health effects of mobile communication networks on children using personal dosimetry. Exposure was assessed every second resulting in 86,400 measurements over 24 h for each participant. Therefore, a functional approach to analyze the exposure data was considered appropriate. The aim was to categorize exposure taking into account the course of the measurements over 24 h. The analyses were based on the 480 maxima of each 3 min time interval. Exposure was classified using a nonparametric functional method. Heterogeneity of a sample of functional data was assessed by comparing the functional mode and mean of the distribution of a functional variable. The partition was built within a descending hierarchical method. The resulting exposure groups were compared with categories derived from a standard method, which used the average exposure over 24 h and set the cut-off at the 90th percentile. The functional classification resulted in a splitting of the exposure data into two groups. Plots of the mean curves showed that the groups could be interpreted as children with "low exposure" (88%) and "higher exposure" (12%). These groups were comparable with categories of the standard method. No association between the categorized exposure and well-being was observed in logistic regression models. The functional classification approach yielded a plausible partition of the exposure data. The comparability with the standard approach might be due to the data structure and should not be generalized to other exposures. Bioelectromagnetics 30:261,269, 2009. © 2009 Wiley-Liss, Inc. [source]

Genetic and morphological variation in a Mediterranean glacial refugium: evidence from Italian pygmy shrews, Sorex minutus (Mammalia: Soricomorpha)

BIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 4 2010
RODRIGO VEGA
At the Last Glacial Maximum (LGM), the southern European peninsulas were important refugia for temperate species. Current genetic subdivision of species within these peninsulas may reflect past population subdivision at the LGM, as in ,refugia within refugia', and/or at other time periods. In the present study, we assess whether pygmy shrew populations from different regions within Italy are genetically and morphologically distinct. One maternally and two paternally inherited molecular markers (cytochrome b and Y-chromosome introns, respectively) were analysed using several phylogenetic methods. A geometric morphometric analysis was performed on mandibles to evaluate size and shape variability between populations. Mandible shape was also explored with a functional approach that considered the mandible as a first-order lever affecting bite force. We found genetically and morphologically distinct European, Italian, and southern Italian groups. Mandible size increased with decreasing latitude and southern Italian pygmy shrews exhibited mandibles with the strongest bite force. It is not clear whether or not the southern Italian and Italian groups of pygmy shrews occupied different refugia within the Italian peninsula at the LGM. It is likely, however, that geographic isolation earlier than the LGM on islands at the site of present-day Calabria was important in generating the distinctive southern Italian group of pygmy shrews, and also the genetic groups in other small vertebrates that we review here. Calabria is an important hotspot for genetic diversity, and is worthy of conservation attention. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 100, 774,787. [source]

The evolutionary ecology of detritus feeding in the larvae of freshwater Diptera

BIOLOGICAL REVIEWS, Issue 1 2009
Athol J. McLachlan
Abstract Detritus (dead organic matter), largely of terrestrial origin, is superabundant in inland waters but because of its indigestible nature, would appear to be a poor food source for animals. Yet this unpromising material is widely used as food and indeed can be viewed as a defining characteristic of the freshwater environment. We here explore the relationships among animals, detritus and its associated micro-organism decomposers, taking a functional approach. We pose questions about interrelationships and attempt to arrive at new insights by disentangling them from an adaptive point of view. To do this we have been careful in selecting the habitats for detailed consideration. Rain pools on rock surfaces in tropical Africa and pools on peat moorland in the UK were chosen. Both examples have a relatively simple community structure and hence offer the prospect of achieving our aim. As model organisms for study we focus principally on the aquatic stages of selected holometabolous insects; that is, selected genera of the universally common midges, Ceratopogonidae and Chironomidae. We approach these case studies from an evolutionary ecology perspective and see detritus as a simple template upon which a beautiful complex of adaptations can evolve. [source]

The ,allosteric modulator' SCH-202676 disrupts G protein-coupled receptor function via sulphydryl-sensitive mechanisms

BRITISH JOURNAL OF PHARMACOLOGY, Issue 4 2006
Anna M Lewandowicz
Previous studies suggest that the thiadiazole compound SCH-202676 (N -(2,3-diphenyl-1,2,4-thiadiazol-5-(2H)-ylidene)methanamine) acts as an allosteric modulator of a variety of structurally distinct G protein-coupled receptors (GPCRs). It was postulated that SCH-202676 would directly bind a structural motif in the receptor molecule common to divergent members of the GPCR family. The molecular mechanisms of such a promiscuous action, however, remain obscure. To clarify the mechanism of SCH-202676 action, we used the functional approach of [35S]GTP,S autoradiography with rat brain cryostat sections together with classical membrane [35S]GTP,S binding assays to evaluate how the thiadiazole affects G protein activity mediated by various receptors linked to the Gi -family of G proteins. We found that in the absence of dithiotreitol (DTT), SCH-202676 (10,7,10,5 M) elicits nonspecific effects in the [35S]GTP,S-based G protein activation assays, thereby severely compromising interpretations on the compounds ability to allosterically inhibit receptor-mediated G protein activity. Such a nonspecific behaviour was fully reversed upon addition of DTT (1 mM), revealing thiol-based mechanism of action. In routine incubations containing DTT, SCH-202676 had no effect on receptor-driven G protein activity, as assessed for adenosine A1, ,2 -adrenergic, cannabinoid CB1, lysophosphatidic acid LPA1, muscarinic M2/M4, purinergic P2Y12 or sphingosine 1-phosphate receptors, suggesting that the thiadiazole does not act as an allosteric modulator of GPCR function. 1H NMR analysis indicated that SCH-202676 underwent structural changes after incubation with the reducing agent DTT or with brain tissue. We conclude that SCH-202676 modulates GPCRs via thiol modification rather than via true allosteric mechanisms. British Journal of Pharmacology (2006) 147, 422,429. doi:10.1038/sj.bjp.0706624 [source]

Preschool children in need of special support: prevalence of traditional disability categories and functional difficulties

ACTA PAEDIATRICA, Issue 1 2010
A Lillvist
Abstract Aim:, To investigate the prevalence of children who are in need of special support in the total population of children attending preschools (CA 1,6) in two Swedish counties, and the functional problems exhibited by the children in relation to demographical and environmental factors in the preschool context. Method:, Survey distributed to (N = 1138) preschools in two Swedish counties. Results:, The majority of children perceived by preschool teachers and in need of special support were undiagnosed children with functional difficulties related to speech, language and interaction with peers. Conclusion:, Undiagnosed and diagnosed children share the same type of difficulties. Thus, in estimating the prevalence of children in need of special support in a preschool context, traditional disability categories capture only a small proportion of the children experiencing difficulties. Therefore, a functional approach in studies of children in need of special support is recommended. [source]