Home About us Contact
|
Home About us Contact | ||
|
|
||
Comprehensive Understanding (comprehensive + understanding)
Selected AbstractsCaregiving behavior and interactions of prenatally depressed mothers (antidepressant-treated and non-antidepressant-treated) during newborn acute pain,INFANT MENTAL HEALTH JOURNAL, Issue 4 2009Fay F. Warnock This exploratory study aimed to examine time-based measures of the behaviors and interactions of prenatally depressed serotonin reuptake inhibitors (SRI)-medicated mothers to their infant's pain (n = 10) by comparing them with similar measures obtained from prenatally depressed nonmedicated mothers and their infants (n = 10), and nondepressed mothers and their infants (n = 10). During the second trimester of their pregnancy, the 30 study mothers were assessed for depression and anxiety, with no further measures of maternal mood taken. Maternal and infant interactions were continuously videorecorded while the infant underwent a scheduled heel lance for routine blood screening that occurred when study infants were between the ages of 24 and 60 hr. Maternal behavior and infant cry, for all 30 cases, were coded second-by-second for the full duration of each infant's heel lance using a reliable coding system and analyzed using odds ratio and regression analyses. Infants exposed to prenatal SRIs and depressed maternal mood were more likely to have lower Apgar scores and to exhibit weak and absent cry. Even when duration of the heel lance was controlled for, women with depression during the second trimester were more likely to exhibit depressed behavior at 2 days' postpartum despite sustained SRI antidepressant treatment. Both groups of prenatally depressed mothers were more likely to exhibit diminished response to their infants' pain cue although nonmedicated mothers' expressions of depressed behavior were more similar to healthy controls. Comprehensive understanding is essential to optimize the clinical care of mothers and their infants in this complex setting. This study contributes preliminary new findings that warrant prospective and longitudinal studies to clarify further the impacts of prenatal SRI and maternal mental mood (e.g., chronic depression and anxiety) effects on the mother,infant interaction and infant pain and stress reactivity. [source] Knowledge Acquisition and Memory Effects Involving an Expert System Designed as a Learning Tool for Internal Control Assessment*DECISION SCIENCES JOURNAL OF INNOVATIVE EDUCATION, Issue 1 2003Mary Jane Lenard ABSTRACT The assessment of internal control is a consideration in all financial statement audits, as stressed by the Statement on Auditing Standards (SAS) No. 78. According to this statement, "the auditor should obtain an understanding of internal control sufficient to plan the audit" (Accounting Standards Board, 1995, p. 1). Therefore, an accounting student will progress through the auditing course with the responsibility of learning how and why internal controls are assessed. Research in expert systems applied to auditing has shown that there is strong support for the constructive dialogue used in expert systems as a means of encouraging their use in decision making (Eining, Jones, & Loebbecke, 1997). The purpose of this study is to provide the student or novice auditor with a method for developing a more comprehensive understanding of internal controls and the use of internal controls in audit planning. The results of the study reinforce previous findings that novices do better when an expert system applies analogies along with declarative explanations, and clarifies the length of time in which the use of active learning in a training system can provide an improvement to declarative knowledge, but procedural knowledge must be acquired over a longer time frame. [source] Measures, perceptions and scaling patterns of aggregated species distributionsECOGRAPHY, Issue 1 2010Cang Hui Non-random (aggregated) species distributions arise from habitat heterogeneity and nonlinear biotic processes. A comprehensive understanding of the concept of aggregation, as well as its measurement, is pivotal to our understanding of species distributions and macroecological patterns. Here, using an individual-based model, we analyzed opinions on the concept of aggregation from the public and experts (trained ecologists), in addition to those calculated from a variety of aggregation indices. Three forms of scaling patterns (logarithmic, power-law and lognormal) and four groups of scaling trajectories emerged. The experts showed no significant difference from the public, although with a much lower deviation. The public opinion was partially influenced by the abundance of individuals in the spatial map, which was not found in the experts. With the increase of resolution (decrease of grain), aggregation indices showed a general trend from significantly different to significantly similar to the expert opinion. The over-dispersion index (i.e. the clumping parameter k in the negative binomial distribution) performed, at certain scales, as the closest index to the expert opinion. Examining performance of aggregation measures from different groups of scaling patterns was proposed as a practical way of analyzing spatial structures. The categorization of the scaling patterns of aggregation measures, as well as their over- and in-sensitivity towards spatial structures, thus not only provides a potential solution to the modifiable areal unit problem, but also unveils the interrelationship among the concept, measures and perceptions of aggregated species distributions. [source] Uptake kinetics and subcellular compartmentalization of cadmium in acclimated and unacclimated earthworms (Eisenia andrei)ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 7 2010Shuo Yu Abstract Acclimation to cadmium (Cd) levels exceeding background concentrations may influence the ability of earthworms to accumulate Cd with minimum adverse effects. In the present study, earthworms (Eisenia andrei) were acclimated by exposure to 20,mg/kg Cd (dry wt) in Webster soil for 28 d. A 224-d bioaccumulation test was subsequently conducted with both acclimated and unacclimated worms exposed in Webster soils spiked with 20,mg/kg and 100,mg/kg Cd (dry wt). Uptake kinetics and subcellular compartmentalization of Cd were examined. Results suggest that acclimated earthworms accumulated more Cd and required a longer time to reach steady state than unacclimated worms. Most of the Cd was present in the metallothionein (MT) fraction. Cadmium in the MT fraction increased approximately linearly with time and required a relatively longer time to reach steady state than Cd in cell debris and granule fractions, which quickly reached steady state. Cadmium in the cell debris fraction is considered potentially toxic, but low steady state concentrations observed in the present study would not suggest the potential for adverse effects. Future use of earthworms in ecological risk assessment should take into consideration pre-exposure histories of the test organisms. A prolonged test period may be required for a comprehensive understanding of Cd uptake kinetics and compartmentalization. Environ. Toxicol. Chem. 2010;29:1568,1574. © 2010 SETAC [source] Nitrided Amorphous Stainless Steel Coatings Deposited by Reactive Magnetron Sputtering from an Austenitic Stainless Steel TargetADVANCED ENGINEERING MATERIALS, Issue 1-2 2009Salvatore Cusenza Abstract Stainless steel films were reactively magnetron sputtered in argon/nitrogen gas flow onto oxidized silicon wafers using austenitic AISI 316 stainless-steel targets. The deposited films of about 300,nm thickness were characterized by conversion electron Mö-i;ssbauer spectroscopy, magneto-optical Kerr-effect, X-ray diffraction, Rutherford backscattering spectrometry, and resonant nuclear reaction analysis. These complementary methods were used for a detailed examination of the nitriding effects for the sputtered stainless-steel films. The formation of an amorphous and soft ferromagnetic phase in a wide range of the processing parameters was found. Further, the influence of postvacuum-annealing was examined by perturbed angular correlation to achieve a comprehensive understanding of the nitriding process and phase formation. The amorphous phase is not very stable and crystallization can be observed at 973,K. [source] Soft ontologies, spatial representations and multi-perspective explorabilityEXPERT SYSTEMS, Issue 5 2008Mauri Kaipainen Abstract: It is against the dynamically evolving nature of many contemporary media applications to be analysed in terms of conventional rigid ontologies that rely on expertise-based fixed categories and hierarchical structure. Many of these rely on sharing ,folksonomies', personal descriptions of information and objects for one's own retrieval. Such applications involve many feedback mechanisms via the community, and have been shown to have emergent properties of complex dynamic systems. We propose that such dynamically evolving information domains can be more usefully described by means of a soft ontology, a dynamically flexible and inherently spatial metadata approach for ill-defined domains. Our contribution is (1) the elaboration of the so far intuitive concept of soft ontology in a way that supports conceptualizing dynamically evolving domains. Further, our approach proposes (2) a whole new mode of interaction with information domains by means of recurring exploration of an information domain from multiple perspectives in search of more comprehensive understanding of it, i.e. multi-perspective exploration. We demonstrate this concept with an example of collaborative tagging in an educational context. [source] Experimental validation of metabolic pathway modelingFEBS JOURNAL, Issue 13 2008An illustration with glycolytic segments from Entamoeba histolytica In the search for new drug targets in the human parasite Entamoeba histolytica, metabolic control analysis was applied to determine, experimentally, flux control distribution of amebal glycolysis. The first (hexokinase, hexose-6-phosphate isomerase, pyrophosphate-dependent phosphofructokinase (PPi -PFK), aldolase and triose-phosphate isomerase) and final (3-phosphoglycerate mutase, enolase and pyruvate phosphate dikinase) glycolytic segments were reconstituted in vitro with recombinant enzymes under near-physiological conditions of pH, temperature and enzyme proportion. Flux control was determined by titrating flux with each enzyme component. In parallel, both glycolytic segments were also modeled by using the rate equations and kinetic parameters previously determined. Because the flux control distribution predicted by modeling and that determined by reconstitution were not similar, kinetic interactions among all the reconstituted components were experimentally revised to unravel the causes of the discrepancy. For the final segment, it was found that 3-phosphoglycerate was a weakly competitive inhibitor of enolase, whereas PPi was a moderate inhibitor of 3-phosphoglycerate mutase and enolase. For the first segment, PPi was both a strong inhibitor of aldolase and a nonessential mixed-type activator of amebal hexokinase; in addition, lower Vmax values for hexose-6-phosphate isomerase, PPi -PFK and aldolase were induced by PPi or ATP inhibition. It should be noted that PPi and other metabolites were absent from the 3-phosphoglycerate mutase and enolase or aldolase and hexokinase kinetics experiments, but present in reconstitution experiments. Only by incorporating these modifications in the rate equations, modeling predicted values of flux control distribution, flux rate and metabolite concentrations similar to those experimentally determined. The experimentally validated segment models allowed ,in silico experimentation' to be carried out, which is not easy to achieve in in vivo or in vitro systems. The results predicted a nonsignificant effect on flux rate and flux control distribution by adding parallel routes (pyruvate kinase for the final segment and ATP-dependent PFK for the first segment), because of the much lower activity of these enzymes in the ameba. Furthermore, modeling predicted full flux-control by 3-phosphoglycerate mutase and hexokinase, in the presence of low physiological substrate and product concentrations. It is concluded that the combination of in vitro pathway reconstitution with modeling and enzyme kinetics experimentation permits a more comprehensive understanding of the pathway behavior and control properties. [source] Microstructure-Lattice Thermal Conductivity Correlation in Nanostructured PbTe0.7S0.3 Thermoelectric MaterialsADVANCED FUNCTIONAL MATERIALS, Issue 5 2010Jiaqing He Abstract The reduction of thermal conductivity, and a comprehensive understanding of the microstructural constituents that cause this reduction, represent some of the important challenges for the further development of thermoelectric materials with improved figure of merit. Model PbTe-based thermoelectric materials that exhibit very low lattice thermal conductivity have been chosen for this microstructure,thermal conductivity correlation study. The nominal PbTe0.7S0.3 composition spinodally decomposes into two phases: PbTe and PbS. Orderly misfit dislocations, incomplete relaxed strain, and structure-modulated contrast rather than composition-modulated contrast are observed at the boundaries between the two phases. Furthermore, the samples also contain regularly shaped nanometer-scale precipitates. The theoretical calculations of the lattice thermal conductivity of the PbTe0.7S0.3 material, based on transmission electron microscopy observations, closely aligns with experimental measurements of the thermal conductivity of a very low value, ,0.8,W,m,1,K,1 at room temperature, approximately 35% and 30% of the value of the lattice thermal conductivity of either PbTe and PbS, respectively. It is shown that phase boundaries, interfacial dislocations, and nanometer-scale precipitates play an important role in enhancing phonon scattering and, therefore, in reducing the lattice thermal conductivity. [source] Elevation gradients of species-density: historical and prospective viewsGLOBAL ECOLOGY, Issue 1 2001MARK. V. Lomolino Abstract Studies of elevation clines in diversity and composition of ecological communities date back to the origins of biogeography. A modern resurgence of interests in these elevational clines is likely to contribute important insights for developing a more general theory of species diversity. In order to gain a more comprehensive understanding of geographical clines in diversity, the research programme for montane biogeography should include statistically rigorous tests of apparent patterns, comparisons of patterns among regions and taxonomic or ecological groups of species, and analyses of clines in environmental variables concurrent with biogeographical surveys. The conceptual framework for this research programme should be based on the assumption that elevational gradients in species diversity result from a combination of ecological and evolutionary processes, rather than the presumed independent effects of one overriding force. Given that montane ecosystems are hot spots of biological diversity, an expanded and integrated programme for biogeographic surveys in montane regions should provide valuable insights for conservation biologists. [source] Electrodeposition of Inorganic/Organic Hybrid Thin FilmsADVANCED FUNCTIONAL MATERIALS, Issue 1 2009Tsukasa Yoshida Abstract Electrodeposition of inorganic compound thin films in the presence of certain organic molecules results in self-assembly of various hybrid thin films with new properties. Examples of new discoveries by the authors are reviewed, taking cathodic formation of a ZnO/dye hybrid as the leading example. Hybridization of eosinY leads to the formation of highly oriented porous crystalline ZnO as the consequence of dye loading. The hybrid formation is a highly complicated process involving complex chemistry of many molecular and ionic constituents. However, electrochemical analyses of the relevant phenomena indicate the possibility of reaching a comprehensive understanding of the mechanism, giving us the chance to further develop them into industrial technologies. The porous crystals are ideal for photoelectrodes in dye-sensitized solar cells. As the process also permits the use of non-heat-resistant substrates, the technology can be applied for the development of colorful and light-weight plastic solar cells. [source] Synthesis, Structure, and Properties of Single-Walled Carbon NanotubesADVANCED MATERIALS, Issue 45 2009Weiya Zhou Abstract Great interest in single-walled carbon nanotubes (SWCNTs) derives from their remarkable electrical, thermal, optical, and mechanical properties together with their lower density, which promise extensive and unique applications. Much progress has been achieved in the fundamental and applied investigations of SWCNTs over the past decade. At the same time, many obstacles still remain, hampering further development in this field. To clarify the emerging problems and to provide a comprehensive understanding of the field, we review the recent progress of research on the synthesis, structure, and properties of SWCNTs, in particular the SWCNT non-woven film, SWCNT rings, boron,nitrogen (B,N) co-doped SWCNTs (BCN-SWNTs), and individual SWCNTs. Some long-standing problems and topics warranting further investigations in the near future are addressed. [source] Mechanisms by which inflammation may increase intestinal cancer risk in inflammatory bowel diseaseINFLAMMATORY BOWEL DISEASES, Issue 8 2010Pamela M. O'Connor PhD Abstract Patients with ulcerative colitis and Crohn's disease are at increased risk of developing intestinal cancers via mechanisms that remain incompletely understood. However, chronic inflammation and repeated events of inflammatory relapse in inflammatory bowel disease (IBD) expose these patients to a number of signals known to have tumorigenic effects including persistent activation of the nuclear factor-,B and cyclooxygenase-2/prostaglandin pathways, release of proinflammatory mediators such as tumor necrosis factor-, and interleukin-6, and enhanced local levels of reactive oxygen and nitrogen species. These inflammatory signals can contribute to carcinogenesis via 3 major processes: 1) by increasing oxidative stress, which promotes DNA mutagenesis thus contributing to tumor initiation; 2) by activating prosurvival and antiapoptotic pathways in epithelial cells, thereby contributing to tumor promotion; and 3) by creating an environment that supports sustained growth, angiogenesis, migration, and invasion of tumor cells, thus supporting tumor progression and metastasis. The present review integrates clinical and basic research observations in an attempt to provide a comprehensive understanding of how inflammatory processes may contribute to intestinal cancer development in IBD patients. (Inflamm Bowel Dis 2010) [source] An inspector calls: farm accommodation providers' attitudes to quality assurance schemes in the county of DevonINTERNATIONAL JOURNAL OF TOURISM RESEARCH, Issue 6 2002Rachel Hill Abstract Estimates suggest that 10,000 farms in the UK offer bed and breakfast (B and B) serviced accommodation. A thorough review of the existing literature indicates over 50% of Devon and Cornwall's farmhouse B and B sector operate without participating in any form of quality assurance inspection scheme. This research executes a stratified postal survey to gain a comprehensive understanding of Devon's farmhouse B and B product, with particular interest in extracting providers' attitudes towards quality assurance inspection schemes. The very representative results suggest a divergence of attitudes towards the notion of quality inspections for all farmhouse B and B providers. Copyright © 2002 John Wiley & Sons, Ltd. [source] Asymmetric coexistence: bidirectional abiotic and biotic effects between goose barnacles and musselsJOURNAL OF ANIMAL ECOLOGY, Issue 4 2006TAKASHI KAWAI Summary 1Species coexistence depends on the net effect of interacting species, representing the sum of multiple interaction components that may act simultaneously and vary independently depending on ambient environmental conditions. Consequently, for a comprehensive understanding of the compound nature of species interactions and coexistence, a mechanistic approach that allows a separate evaluation of each interaction component is required. 2Two sessile filter-feeders, the goose barnacle Capitulum mitella and the mussel Septifer virgatus, coexist on moderately wave-exposed rocky shores in south-western Japan. In the upper intertidal, Capitulum positively influenced Septifer survivorship and growth through amelioration of thermal stress and of physical disturbance. On the other hand, these species are potential competitors as they have similar body sizes and modes of resource utilization. These opposite processes, facilitation and competition, are based on abiotic characteristics and biotic functions of the two species, respectively. 3In order to quantify the bidirectional abiotic, biotic and net effects, a series of experimental manipulations was conducted involving the use of living neighbours with both abiotic and biotic effects, and artificial mimics to simulate abiotic effects without biotic effects. 4Capitulum had strong positive abiotic effects on the mussel survivorship in most experimental periods, while the biotic effect was negligible or weakly negative, suggesting that the net effect of Capitulum on mussel survival was largely attributable to the abiotic effect. In contrast, a significantly negative biotic effect on the mussel growth rate was always present, though this was cancelled out by the larger, positive abiotic effect. In the case of Septifer, its abiotic and biotic effects on the survivorship of goose barnacles were negligible, while those on the growth rate showed temporal variation. 5With respect to the relationship between species interaction and environmental conditions, the strength of abiotic facilitative effect of Capitulum on mussel survival increased with increasing abiotic stress, while the strength of biotic effect was negligible or weakly negative. As regards the effects of mussels on goose barnacles, our study indicated no obvious relationship. These results point to the importance of decomposing interaction for an accurate, mechanistic understanding of species relations and coexistence. [source] Spatial abundance structures in an assemblage of gall-forming sawfliesJOURNAL OF ANIMAL ECOLOGY, Issue 3 2004M. A. McGeoch Summary 1Examination of the fine-scale internal structure of species geographical ranges, and interspecific variation therein across landscapes, contributes to a more comprehensive understanding of the structure of geographical ranges. Two components of this internal structure that require further examination are the occurrence, extent and position of spatial autocorrelation, and relationships between the spatial abundance structures of closely related, ecologically similar species. 2Here we compare the abundance structures of an assemblage of gall-forming sawflies (Tenthredinidae) across a landscape. We identify the relative roles of spatial and non-spatial factors in explaining their abundance structures and test the hypothesis that sawfly density is explained by host plant quality, as has been demonstrated repeatedly at finer scales. We use these results to distinguish between alternative sets of mechanisms that may be operating at the landscape scale. 3Species densities were mainly multimodal across the landscape and significantly spatially structured, with patch, periodic and trend components. The abundance structures thus mimic those found generally for species across the full extent of their geographical ranges. 4Many abundance structure characteristics were unique to species, with differences in their correlogram profiles, distances over which densities were positively autocorrelated, and the absence of significant spatial structure in one species. 5In contrast to previous, fine-scale studies, host plant quality explained little of the variation in sawfly gall density across the landscape, whereas unexplained spatial structure contributed between 30% and 50%. Based on knowledge of the biology of these species and the absence of competitive interactions, species dispersal characteristics and the Moran effect are suggested as probable alternative hypotheses at this scale. 6Therefore, a spatial approach has identified the hierarchical nature of mechanisms underlying the population dynamics of this sawfly assemblage for the first time. Furthermore, it has highlighted the importance of spatial processes in explaining the densities of species at the landscape scale, as well as the individualistic nature of their abundance structures. [source] Multiple differentiation centres of a non-Mediterranean butterfly species in south-eastern EuropeJOURNAL OF BIOGEOGRAPHY, Issue 6 2007Thomas Schmitt Abstract Aim, The analysis of the phylogeographical structures of many European species reveals the importance of Mediterranean glacial refugia for many thermophilic species, but also underlines the relevance of extra-Mediterranean glacial differentiation centres for a number of temperate species. In this context, phylogeographical analyses of species from south-eastern Europe are highly important for a comprehensive understanding of Europe as a whole. Location, Romania and Bulgaria. Methods, We analysed 19 allozyme loci for 615 individuals of the temperate butterfly species Erebia medusa from 28 populations. Results, These populations had an intermediate genetic diversity, but the Bulgarian populations were significantly more diverse than the ones north of the Danube in Romania. The differentiation among populations was strong, and 52.1% of the genetic variance among populations was distributed between these two countries. The genetic differentiation was considerably stronger in Romania than in Bulgaria, but several sublineages were distinguished within each of these countries. Main conclusions, The observed genetic structure is so strong that it is most probably the result of glacial differentiation processes in south-eastern Europe and not a post-glacial structure. The strong differentiation into the two groups north and south of the Danube suggests a separating effect by this river valley. The strong differentiation accompanied with genetic impoverishment in Romania suggests the existence of several differentiation centres: at least two small ones on the southern slopes of the southern Carpathians and one in the eastern Carpathian Basin. The considerably weaker differentiation among the Bulgarian samples and their significantly higher genetic diversity imply that gene flow occurred among different regions of Bulgaria during the last ice age. [source] The island rule and a research agenda for studying ecogeographical patternsJOURNAL OF BIOGEOGRAPHY, Issue 9 2006Mark V. Lomolino Abstract We are currently experiencing a resurgence of interest in ecogeographical rules, which describe general trends in morphology and related traits along geographical gradients. In order to develop a more comprehensive understanding of the generality and underlying causal mechanisms for these patterns, we recommend a new, more integrated research agenda. In particular, we recommend studies that simultaneously consider different clines in morphology, geographical ranges and diversity as intricately related phenomena; all being ecological, evolutionary and biogeographical responses of organisms to selection regimes that vary non-randomly over space and time, and among species with different ecological and evolutionary histories. [source] Dysregulated BMP Signaling and Enhanced Osteogenic Differentiation of Connective Tissue Progenitor Cells From Patients With Fibrodysplasia Ossificans Progressiva (FOP),JOURNAL OF BONE AND MINERAL RESEARCH, Issue 3 2008Paul C Billings Abstract The study of FOP, a disabling genetic disorder of progressive heterotopic ossification, is hampered by the lack of readily available connective tissue progenitor cells. We isolated such cells from discarded primary teeth of patients with FOP and controls and discovered dysregulation of BMP signaling and rapid osteoblast differentiation in FOP cells compared with control cells. Introduction: Fibrodysplasia ossificans progressiva (FOP), the most disabling condition of progressive heterotopic ossification in humans, is caused by a recurrent heterozygous missense mutation in activin receptor IA (ACVR1), a bone morphogenetic protein (BMP) type I receptor, in all classically affected individuals. A comprehensive understanding of FOP has been limited, in part, by a lack of readily available connective tissue progenitor cells in which to study the molecular pathology of this disorder. Materials and Methods: We derived connective tissue progenitor cells from discarded primary teeth (SHED cells) of patients with FOP and controls and examined BMP signaling and osteogenic differentiation in these cells. Results: SHED cells transmitted BMP signals through both the SMAD and p38 mitogen-activated protein kinase (MAPK) pathways and responded to BMP4 treatment by inducing BMP responsive genes. FOP cells showed ligand-independent BMP signaling and ligand-dependent hyper-responsiveness to BMP stimulation. Furthermore, FOP cells showed more rapid differentiation to an osteogenic phenotype than control cells. Conclusions: This is the first study of BMP signaling and osteogenic differentiation in connective tissue progenitor cells from patients with FOP. Our data strongly support both basal and ligand-stimulated dysregulation of BMP signaling consistent with in silico studies of the mutant ACVR1 receptor in this condition. This study substantially extends our understanding of dysregulated BMP signaling in a progenitor cell population relevant to the pathogenesis of this catastrophic disorder of progressive ectopic ossification. [source] Application of Histomorphometric Methods to the Study of Bone Repair,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 10 2005Louis C Gerstenfeld Abstract ABSTRACT: Standardized methods for the histomorphometric assessment of bone are essential features of most studies of metabolic bone diseases and their treatments. These methodologies were developed to assess coupled remodeling, focusing primarily on osteoblasts and osteoclasts, the anabolic and catabolic rates of these cells, and structural features of mature bone. Research studies on bone healing and the development of new therapeutic approaches for the enhancement of bone repair also require a comprehensive understanding of the basic cellular and tissue level mechanisms that underlie these processes. However, the histological methods developed for metabolic bone disease studies are not completely suitable for studies of bone repair because they are based on assumptions that there is little variation in tissue composition within a sample of bone and not generally designed to quantify other types of tissues, such as cartilage, that contribute to bone healing. These techniques also do not provide tissue-based structural measurements that are relatable to the specific types of biomechanical and radiographic structural assessments that are used to determine rates of bone healing. These deficiencies in current histological approaches therefore point to the need to establish standardized criteria for the histomorphometric assessments that are specifically adapted for the study of bone repair in models of fracture healing and bone regeneration. In this Perspective, we outline what we believe to be the specific structural, tissue. and cellular aspects that need to be addressed to establish these standardized criteria for the histomorphometric assessment of bone repair. We present the specific technical considerations that need to be addressed to appropriately sample repair tissues to obtain statistically meaningful results and suggest specific procedures and definitions of nomenclatures for the application of this technology to bone repair. Finally, we present how aspects of histomorphometric measurements of bone repair can be related to biomechanical and radiographic imaging properties that functionally define rates of bone healing, and thus, how these tools can be used to provide corroborating data. [source] Interactions Between Extracellular Stimuli and Excitation Waves in an Atrial Reentrant LoopJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 10 2003CHAD R. JOHNSON B.S.E. Introduction: The interactions between extracellular stimuli and excitation waves propagating in a reentrant loop are a complex function of stimulus parameters, structural properties, membrane state, and timing. Here the goal was a comprehensive understanding of the mechanisms and frequencies of the major interactions between the advancing excitation wave and a single extracellular stimulus, separated from issues of anatomic or geometric complexity. Methods and Results: A modernized computer model of a thin ring of uniform tissue that included a pair of extracellular stimulus electrodes (anode/cathode) was used to model one-dimensional cardiac reentry. Questions and results included the following: (1) What are the major interactions between a stimulus and the reentrant propagation wave, and are they induced near the cathode or near the anode; and, for each interaction, what are the initiating amplitude range and timing interval? At the cathode, the well-known mechanism of retrograde excitation terminated reentry; changes in timing or amplitude produced double-wave reentry or phase reset. At the anode, termination occurred at different cells depending on stimulus amplitude. (2) Relatively how often did termination occur at the anode? For most stimulus amplitudes, termination occurred more often at the anode than at the cathode, although not always at the same cell. (3) With random timing, what is the probability of terminating reentry? Stimulation for 5 msec terminated reentry with a probability from 0% to approximately 10%, as a function of increasing stimulus amplitude. Conclusion: A single extracellular stimulus can initiate major changes in reentrant excitation via multiple mechanisms, even in a simple geometry. Termination of reentry, phase shifts, or double-wave reentry each occurs over well-defined ranges of stimulus amplitude and timing. (J Cardiovasc Electrophysiol, Vol. 14, pp. ***-***, October 2003) [source] Effectiveness of maternity support belts in reducing low back pain during pregnancy: a reviewJOURNAL OF CLINICAL NURSING, Issue 11 2009Simone SM Ho Aims., This article aims to review the literature published to date on the types, current use, the biomechanical effects and adverse effects of maternity support belts for low back pain during pregnancy, to identify future research directions. Background., Lumbar/pelvic support belts are frequently recommended for the prevention and treatment of low back pain during pregnancy. Design., Systematic review. Methods., MEDLINE, CINAHL, the Cochrane Library and patents databases were electronically searched. Results., Maternity support belts belong to one of the four main types of maternity support garments, which are widely commercially-available. Current research showed limited evidence in support of the commercial maternity products regarding the effectiveness in the prevention and/or treatment of low back pain during pregnancy, other than that from the manufacturers. However, potential stabilisation effect of maternity support belt was demonstrated in some studies. Adverse effects reported include increased pain, fetal heart rate changes, skin irritation and discomfort. Conclusions., There is insufficient scientific evidence to conclude that wearing maternity support belts reduces pregnancy-related low back pain and/or pelvic girdle pain. Future research directions in the area of biomechanics and physiology are recommended. Relevance to clinical practice., This review provides comprehensive understanding of the effectiveness of maternity support belts for the relief of low back pain during pregnancy which will facilitate healthcare professionals in providing evidence-based advice to their patients. [source] Review: evaluating information systems in nursingJOURNAL OF CLINICAL NURSING, Issue 5 2008Cristina Oroviogoicoechea MSc Aims., To review existing nursing research on inpatient hospitals' information technology (IT) systems in order to explore new approaches for evaluation research on nursing informatics to guide further design and implementation of effective IT systems. Background., There has been an increase in the use of IT and information systems in nursing in recent years. However, there has been little evaluation of these systems and little guidance on how they might be evaluated. Methods., A literature review was conducted between 1995 and 2005 inclusive using CINAHL and Medline and the search terms ,nursing information systems', ,clinical information systems', ,hospital information systems', ,documentation', ,nursing records', ,charting'. Results., Research in nursing information systems was analysed and some deficiencies and contradictory results were identified which impede a comprehensive understanding of effective implementation. There is a need for IT systems to be understood from a wider perspective that includes aspects related to the context where they are implemented. Conclusions., Social and organizational aspects need to be considered in evaluation studies and realistic evaluation can provide a framework for the evaluation of information systems in nursing. Relevance to clinical practice., The rapid introduction of IT systems for clinical practice urges evaluation of already implemented systems examining how and in what circumstances they work to guide effective further development and implementation of IT systems to enhance clinical practice. Evaluation involves more factors than just involving technologies such as changing attitudes, cultures and healthcare practices. Realistic evaluation could provide configurations of context-mechanism-outcomes that explain the underlying relationships to understand why and how a programme or intervention works. [source] On mental events, disciplinary boundaries, and reductionism: A reply to PlaudJOURNAL OF CLINICAL PSYCHOLOGY, Issue 9 2001Stephen S. Ilardi Plaud's (2001) radical behavioral manifesto suggests that a psychological science based exclusively upon the study of environment-behavior functional contingencies would yield a discipline unencumbered by mentalism, vaguely delineated disciplinary boundaries, or inappropriate reductionism. In reply, we note that: (a) mental events,e.g., thoughts and feelings,are increasingly accessible to objective investigation, and provide an observable proximal causal mechanism for the environmental selection of behavior; (b) the call for pristine disciplinary boundaries is anachronistic, inasmuch as progress in the natural sciences has engendered disciplinary boundaries that are increasingly porous; (c) cognitive neuroscience facilitates a comprehensive understanding of complex human behavior by mapping out the relationship between such behavior and underlying brain events, thereby engaging in an appropriate form of reductionism (constitutive reductionism) that has become a hallmark of the natural sciences; and (d) ironically, it is radical behaviorism, in its disavowal of the informational level of complexity instantiated in brain events, that engages in inappropriate eliminative reductionism (i.e., reducing neural information to "nothing but" its underlying bring states). © 2001 Jo n Wiley & Sons, Inc. J Clin Psychol 57: 1103,1107, 2001. [source] Helpseeking behavior among Filipino Americans: A cultural analysis of face and languageJOURNAL OF COMMUNITY PSYCHOLOGY, Issue 5 2003Fang Gong In this study we explore the existing research on Asian Americans and helpseeking behavior, focusing primarily on Filipino Americans and the cultural variables of face and language. Although some important and specific cultural factors have been hypothesized to affect the helpseeking behaviors of ethnic minorities, very few empirical studies have been conducted to specifically test these hypotheses. To fill the gaps in previous research, we examined the influence of concern with face and of language abilities on helpseeking behavior for mental health problems among Filipino Americans. In addition, to obtain a more comprehensive understanding of helpseeking behavior, we divided the mental health care systems into four categories: lay, mental health specialty, general practitioner, and folk systems. Data are from the Filipino American Epidemiological Study (FACES) survey. The main statistical method we employed was logistic regression. Results from the descriptive analyses reveal that the lay system is the most frequently used source of care compared with the other systems of professional and folk systems for Filipino Americans. Furthermore, findings from the main effects models suggest that face and language are important cultural factors that contribute to the helpseeking behavior of Filipino Americans, but they have different influences on the four types of mental health care systems. The interaction analyses indicate that concern with face interacts with language abilities when predicting use of the lay system and the general medical sector. Despite these findings, to fully understand the dynamics of helpseeking, other cultural factors and longitudinal studies are needed. © 2003 Wiley Periodicals, Inc. J Comm Psychol 31: 469,488, 2003. [source] Organizing learning materials through hierarchical topic maps: an illustration through Chinese herb medicationJOURNAL OF COMPUTER ASSISTED LEARNING, Issue 6 2007B.-J. Shih Abstract This research aims to use hierarchical topic maps to compile digital learning material and to discuss its design and application possibilities. The system renders tremendous original assets and then embeds a self-organizing map (SOM) in the material database to produce topical learning materials, as in this case, an illustration through Chinese herb medication. It helps to demonstrate robust professional information as well as knowledge structures, and provides a customized and interactive learning dynamic to support both progressive and constructive learning styles. The paper first gives a detailed procedural description of the material construction, explains how topic map techniques were applied, and observes the implications and potentials of the technology to education. Both the technical and educational evaluations of using SOM topic maps in compilation of learning materials have resulted in positive feedback. SOM allows users to review the complete databank in structural hierarchical order, which provides comprehensive understanding of the entire set of learning materials, and also brings opportunities to users to discover knowledge related to their study area. [source] PHYSICOCHEMICAL AND PROCESSING FUNCTIONAL PROPERTIES OF PROTEINS FROM TWO CHINESE CHICKPEA (CICER ARIETINUM L.) CULTIVARSJOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 4 2010WEN-RUI GAO ABSTRACT The physicochemical and functional properties of protein isolates from two Chinese chickpea cultivars were investigated and compared with those of SPI. GCPI has the lightest, reddest, most yellow and highest chroma. SHF and Ho of three protein isolates were significantly different (P < 0.05). Significant differences (P < 0.05) in EAI, FC, FS and LGC were observed between the two chickpea protein isolates, whose most functional properties were inferior to those of SPI. Most textural properties of heated gels from two chickpea protein isolates were similar and were also inferior to those of the SPI heated gel. PRACTICAL APPLICATIONS Chickpea is the third most widely grown grain legume crop in the world after bean and soybean. In the present study, we examined the physicochemical properties (chemical composition, color characteristics, SHF content and Ho) and functional properties (nitrogen solubility, emulsifying properties, WHC and OHC, FC and FS, and gelation properties) of protein isolates derived from Desi and Kabuli chickpea cultivars grown in Xinjiang Autonomous Region in China, and compared them with those of SPI. This study would be useful in the comprehensive understanding of the characteristics of chickpea protein and its use as a potential additive for food and dietary items. [source] An ongoing process of inner negotiation , a Grounded Theory study of self-management among people living with chronic illnessJOURNAL OF NURSING AND HEALTHCARE OF CHRONIC ILLNE SS: AN INTERNATIONAL INTERDISCIPLINARY JOURNAL, Issue 4 2009Åsa Audulv RN Aim., The aim of this study was to better understand the main concern of self-management processes among people with chronic illness. Background., One aspect of living with chronic illness is self-management that can reduce the illness impact on daily life and promote future health. Although factors that influence self-management have been identified in previous research, little attention has been brought to the process of making self-management decisions. In clinical settings, use of a theory could facilitate patient-empowering approaches. Method., The data collection for this Grounded Theory was mostly conducted in 2006. Data were collected by interviews with 26 adults with a variety of chronic illnesses, including rheumatoid arthritis, diabetes mellitus, inflammatory bowel syndrome, multiple sclerosis, ischaemic heart disease and chronic kidney failure. Results., Individuals are conflicted by competing preferences when taking decisions about self-management. Consequently, the decision-making process can be understood as an ongoing inner negotiation between different incompatible perspectives, e.g. social needs vs. medical needs. The process of negotiating self-management starts with the individual's considering beliefs about health and illness, which make the individual face illness threats and the need for self-management. Several aspects influence negotiating self-management namely, assessing effects of self-management; evaluating own capacity; perceiving normality or stigmatisation; and experiencing support and external resources. The process has been demonstrated in a model. Conclusions., The process of negotiating self-management is an ongoing inner debate rather than a one-time decision. This opens up new ways of understanding, and communicating with, patients. The described model also links behavioural theories and research findings in a comprehensive understanding. Relevance to clinical practice., This model could be applicable as a communication tool for health-care providers in identifying barriers to, and resources in, self-management behaviour among individuals with chronic illness. [source] Caring for Pregnant Teenagers: Medicolegal Issues for NursesJOURNAL OF OBSTETRIC, GYNECOLOGIC & NEONATAL NURSING, Issue 2 2001CRNP, Holly M. Harner MSN From statutory rape, pregnancy options, mandatory reporting, and emancipation, a wide range of medicolegal issues face teenagers. These issues become even more complex when the teenager is pregnant. Nurses caring for pregnant and parenting teenagers are in a position to offer advocacy and support in family planning, prenatal, obstetric, and pediatrics settings. A comprehensive understanding of common medicolegal issues facing teenagers will help to ensure appropriate patient advocacy. [source] Mechanical properties of the scapholunate ligament correlate with bone mineral density measurements of the handJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 4 2004James D. Johnston Abstract The mechanical properties of the scapholunate ligament have been previously examined in small sample sizes, with ultimate load and occasionally stiffness reported. The present study examined 16 scapholunate ligaments in uniaxial extension at two rates and determined stiffness, ultimate load, and stress relaxation properties. Mean stiffness values of 66.4 ± 28.6 N/mm at an elongation rate of 50 mm/min and 94.5 ± 44.4 N/mm at an elongation rate of 100 mm/min were found. Relaxation behavior, determined by the percent load remaining after 100 s, was found to be 68.1 ± 12%. Mean ligament ultimate loads were 357 ± 110 N (n = 8). In eight specimens, failure occurred in bone. Positive correlations were observed between bone mineral density of the hand and ligament stiffness, ligament ultimate load, and bone ultimate load. No correlation was observed between bone mineral density and ligament load relaxation behavior. The results provide a comprehensive understanding of scapholunate ligament biomechanics and demonstrate a relationship between bone and ligament properties. © 2004 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved. [source] Ontogeny of the Enhanced Fetal-Ethanol-Induced Behavioral and Neurophysiologic Olfactory Response to Ethanol OdorALCOHOLISM, Issue 2 2010Amber M. Eade Background:, Studies report a fundamental relationship between chemosensory function and the responsiveness to ethanol, its component orosensory qualities, and its odor as a consequence of fetal ethanol exposure. Regarding odor, fetal exposed rats display enhanced olfactory neural and behavioral responses to ethanol odor at postnatal (P) day 15. Although these consequences are absent in adults (P90), the behavioral effect has been shown to persist into adolescence (P37). Given the developmental timing of these observations, we explored the decay in the response to ethanol odor by examining ages between P37 and young adulthood. Moreover, we sought to determine whether the P15 neurophysiologic effect persists, at least, to P40. Methods:, Behavioral and olfactory epithelial (OE) responses of fetal ethanol exposed and control rats were tested at P40, P50, P60, or P70. Whole-body plethysmography was used to quantify each animal's innate behavioral response to ethanol odor. We then mapped the odorant-induced activity across the OE in response to different odorants, including ethanol, using optical recording methods. Results:, Relative to controls, ethanol exposed animals showed an enhanced behavioral response to ethanol odor that, while significant at each age, decreased in magnitude. These results, in conjunction with previous findings, permitted the development of an ontologic odor response model of fetal exposure. The fitted model exemplifies that odor-mediated effects exist at birth, peak in adolescence and then decline, becoming absent by P90. There was no evidence of an effect on the odor response of the OE at any age tested. Conclusions:, Fetal exposure yields an enhanced behavioral response to ethanol odor that peaks in adolescence and wanes through young adulthood. This occurs absent an enhanced response of the OE. This latter finding suggests that by P40 the OE returns to an ethanol "neutral" status and that central mechanisms, such as ethanol-induced alterations in olfactory bulb circuitry, underlie the enhanced behavioral response. Our study provides a more comprehensive understanding of the ontogeny of fetal-ethanol-induced olfactory functional plasticity and the behavioral response to ethanol odor. [source] | |||||||||||||||||||||||||||||||||||||