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Selected AbstractsA NEW METHOD FOR STUDYING THE EXTENT, STABILITY, AND PREDICTORS OF INDIVIDUAL SPECIALIZATION IN VIOLENCE,CRIMINOLOGY, Issue 2 2007D. WAYNE OSGOOD Specialization in violence is an important scientific and policy topic, and over the past several decades, many analysis techniques for studying specialization have emerged. Research in this area continues to be hampered, however, by remaining methodological problems. To overcome these problems, we propose a new method for studying specialization in violence based on an item-response theory measurement approach that is implemented through a multilevel regression model. Our approach defines specialization as an individual level latent variable, takes into account the inherent confounds between specialization and overall level of offending, and gauges specialization relative to the population base rates of each offense. Our method also enables researchers to 1) estimate the extent and statistical significance of specialization, 2) assess the stability of specialization over time, and 3) relate specialization to explanatory variables. Using data from three studies, we found substantial levels of specialization in violence, considerable stability in specialization over time, and several significant and relatively consistent relationships of specialization to explanatory variables such as gender, parental education, and risk-seeking. [source] RESPONSE SURFACE METHODOLOGY FOR STUDYING THE QUALITY CHARACTERISTICS OF COWPEA (VIGNA UNGUICULATA)-BASED TEMPEHJOURNAL OF FOOD PROCESS ENGINEERING, Issue 4 2010GEORGE AMPONSAH ANNOR ABSTRACT Response surface methodology was used to optimize the processing conditions in the preparation of cowpea tempeh. The independent factors studied were boiling time (varying from 5 to 30 min), incubation time (varying from 12 to 48 h) and incubation temperatures (varying from 25 to 50C), whereas the dependent factors were protein content, protein solubility, pH, titratable acidity and total color difference (using L, a* and b*). Regression models were generated and adequacy was tested with regression coefficients (R2) and the lack-of-fit tests. Optimum processing conditions were determined by method of superimposition. There was a strong and significant influence (P < 0.01) of the quadratic effect of the incubation time on the protein content of the cowpea tempeh, with similar significance (P < 0.01) noted in protein solubility with increasing boiling time. The optimum processing conditions observed for the preparation of cowpea tempeh were boiling time of about 20 min, incubation time of about 28 h and incubation temperature of about 37C. PRACTICAL APPLICATIONS Response surface methodology (RSM), as a statistical tool, has been effectively used in food process applications. This study embraced the use of RSM in the optimization of the processing conditions involved in the preparation of cowpea tempeh. Superimposition of the contour plots developed from the regression models indicated that cowpea with optimum quality characteristics should be processed at a boiling time of 20 min, incubation time of 28 h and incubation temperature of 37C. These conditions could be adopted for the industrial production of cowpea tempeh. [source] METHODS FOR STUDYING THE PHYSIOLOGY OF KIDNEY OXYGENATIONCLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 12 2008Roger G Evans SUMMARY 1An improved understanding of the regulation of kidney oxygenation has the potential to advance preventative, diagnostic and therapeutic strategies for kidney disease. Here, we review the strengths and limitations of available and emerging methods for studying kidney oxygen status. 2To fully characterize kidney oxygen handling, we must quantify multiple parameters, including renal oxygen delivery (DO2) and consumption (VO2), as well as oxygen tension (Po2). Ideally, these parameters should be quantified both at the whole-organ level and within specific vascular, tubular and interstitial compartments. 3Much of our current knowledge of kidney oxygen physiology comes from established techniques that allow measurement of global kidney DO2 and VO2, or local tissue Po2. When used in tandem, these techniques can help us understand oxygen mass balance in the kidney. Po2 can be resolved to specific tissue compartments in the superficial cortex, but not deep below the kidney surface. We have limited ability to measure local kidney tissue DO2 and VO2. 4Mathematical modelling has the potential to provide new insights into the physiology of kidney oxygenation, but is limited by the quality of the information such models are based on. 5Various imaging techniques and other emerging technologies have the potential to allow Po2 mapping throughout the kidney and/or spatial resolution of Po2 in specific renal tissues, even in humans. All currently available methods have serious limitations, but with further refinement should provide a pathway through which data obtained from experimental animal models can be related to humans in the clinical setting. [source] When It Comes to Mechanism, Is It Worth Studying Any Other Species Besides Mice?ETHOLOGY, Issue 12 2007Gregory F. Ball No abstract is available for this article. [source] INTERGENOMIC EPISTASIS AND COEVOLUTIONARY CONSTRAINT IN PLANTS AND RHIZOBIAEVOLUTION, Issue 5 2010Katy D. Heath Studying how the fitness benefits of mutualism differ among a wide range of partner genotypes, and at multiple spatial scales, can shed light on the processes that maintain mutualism and structure coevolutionary interactions. Using legumes and rhizobia from three natural populations, I studied the symbiotic fitness benefits for both partners in 108 plant maternal family by rhizobium strain combinations. Genotype-by-genotype (G × G) interactions among local genotypes and among partner populations determined, in part, the benefits of mutualism for both partners; for example, the fitness effects of particular rhizobium strains ranged from uncooperative to mutualistic depending on the plant family. Correlations between plant and rhizobium fitness benefits suggest a trade off, and therefore a potential conflict, between the interests of the two partners. These results suggest that legume,rhizobium mutualisms are dynamic at multiple spatial scales, and that strictly additive models of mutualism benefits may ignore dynamics potentially important to both the maintenance of genetic variation and the generation of geographic patterns in coevolutionary interactions. [source] THE STORM OF NOVEMBER 1826 IN THE CANARY ISLANDS: POSSIBLY A TROPICAL CYCLONE?GEOGRAFISKA ANNALER SERIES A: PHYSICAL GEOGRAPHY, Issue 3 2010JOSÉ BETHENCOURT-GONZÁLEZ ABSTRACT. This work analyses a storm that occurred in the Canary Islands early in November 1826. Through a study based on historical climate data, some of the adverse effects of the storm are described and some of the possible causes are discussed. The main goal of this work is to establish an approximate reconstruction of this historical event which will allow us to compare it to a recent meteorological event that had a great impact on the archipelago: "Tropical Storm Delta", in November 2005. Studying and reviewing the origin of the 1826 storm verifies the hypothesis that extremely violent perturbations have not only occurred in the Canaries on other occasions, but that these past events were also more intense and had more serious consequences than Delta. Therefore, the idea that other tropical perturbations have occurred in the region of the Canary Islands before Delta is presented. [source] Swimming against the tide: Outward staffing flows from multinational subsidiariesHUMAN RESOURCE MANAGEMENT, Issue 4 2010David G. Collings Abstract Studying the flows of parent country nationals in multinational enterprises (MNEs) to subsidiary operations has a relatively long tradition. Studying flows of subsidiary employees to other subsidiaries, as third country nationals, and to the corporate headquarters, as inpatriates, however, has empirically much less pedigree. Drawing on a large-scale empirical study of MNEs in Ireland, this paper provides a benchmark of outward flows of international assignees from the Irish subsidiaries of foreign-owned MNEs to both corporate headquarters and other worldwide operations. Building on insights from the resource-based view and neo-institutional theory, we develop and test a theoretical model to explain outward staffing flows. The results show that almost half of all MNEs use some form of outward staffing flows from their Irish operations. Although the impact of specific variables in explaining inter-organization variation differs between the utilization of inpatriate and third country national assignments, overall we find that a number of headquarters, subsidiary, structural, and human resource systems factors emerge as strong predictors of outward staffing flows. © 2010 Wiley Periodicals, Inc. [source] Studying and increasing light stability of rotomolding grade of polyethyleneJOURNAL OF APPLIED POLYMER SCIENCE, Issue 3 2008E. Feyz Abstract This article covers the state-of-the-art light stabilizer for rotational molding and the influence of synergistic effects between light and thermal stabilizers, which improve physical and mechanical properties. Different formulations of polyethylene (PE) with light stabilizer, thermal stabilizer, and acid scavenger have been produced in twin-screw extruder. To study the light stability, sheets that produced by injection-molding machine have been put in weather-ometer instrument for 1000 h. After and before that, physical and mechanical properties have been evaluated. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 [source] Directed Thinking and Readiness to Change Self-Beneficial Behaviors: Are You Ready for Some Studying?JOURNAL OF APPLIED SOCIAL PSYCHOLOGY, Issue 10 2007Heather A. Labansat Previous research has suggested that intentions to engage in studying and other self-beneficial activities might be promoted more by thinking about actions one could take than by thinking about reasons for doing so. The present experiments assessed whether the relative efficacy of actions vs. reasons might depend on individuals' readiness to change. Consistent with previous findings on the processes of change most relevant in different stages, the benefits of self-generated actions were more pronounced for participants who were in the later stages of change. This "matching-to-stage" relationship occurred in 2 experiments that differed in stage measurement, how thinking was directed, and which outcomes were measured. The results have both practical and theoretical implications for attempts to change self-beneficial behaviors. [source] Effect of the Amount of Hours Spent Studying on the Prevalence of Overactive Bladder in College WomenLUTS, Issue 2 2010Dong Gil SHIN Objectives: We conducted a questionnaire survey to access whether the amount of hours spent studying has an effect on the prevalence of OAB in college women. Methods: A total of 126 (63%; mean: 23.2 years) of 200 women participants completed the questionnaire. They were divided into two groups: group A (weekly studying hour >40 h) consisted of medical female students and group B (weekly studying hour <25 h) consisted of French literature woman students. The factors related to OAB were analyzed by the chi-squared test. Results: Of 126 respondents, the prevalence of OAB was prevalent in 38 (30.2%) women. There was significant difference in prevalence between the two groups: 7.0% for group A and 42.2% for group B. In group B, OAB prevalence was 66.7% for ,2 h, 41.2% for 2,,4 h, 46.5% for 4,,6 h, and >6 h was 23.5%. This survey showed that there is no relationship between the amount of hours spent studying and OAB. Conclusion: Although the amount of hours spent studying had no association with OAB in college women, OAB prevalence showed a decreasing pattern as the quantity of studying hour increases. Consequently, it is thought that the attitude toward study has more association with OAB than the quantity of studying hours. [source] Time-Resolved Small-Angle Neutron Scattering as a Tool for Studying Controlled Release from Liposomes using Polymer-Enzyme ConjugatesMACROMOLECULAR RAPID COMMUNICATIONS, Issue 19 2010Elaine L. Ferguson Abstract The action of phospholipase A2 (PLA2) on 1,2-dipalmitoyl- sn -glycero-3-phosphocholine (DPPC) liposomes (vesicles) , an integral component in the polymer enzyme liposome therapy (PELT) mechanism (R. Duncan et al., J. Controlled Release2001, 74, 135) for the controlled delivery of poorly soluble therapeutic molecules within liposomes , may be "masked" by conjugation to the biodegradable polymer dextrin and subsequently regenerated by the endogenous enzyme , -amylase that degrades the dextrin; that is, incorporating the so-called polymer-unmasked-masked protein therapy (PUMPT) approach (R. Duncan, et al. Biomacromolecules2008, 9, 1146). Small-angle neutron scattering (SANS) has been used to quantify the detailed structure of DPPC liposomes and any perturbation in that structure induced by the presence of PLA2 in native, "masked" (dextrin,PLA2 conjugate) and an in situ , -amylase-unmasked form. A time-dependent degradation of the vesicular structure was observed for the two active PLA2 cases, but not for the masked case. This study demonstrates that the PLA2 -induced hydrolysis of the DPPC , and the associated rupture of the liposome and the release of the enclosed material , may be controlled through masking with dextrin. Accordingly, the viability of using such a combinatorial nanomedicine approach as a general route for the controlled delivery of poorly soluble therapeutic molecules is shown. [source] A Discrete, Space Variation Model for Studying the Kinetics of Shape Deformation of Vesicles Coupled with Phase SeparationMACROMOLECULAR THEORY AND SIMULATIONS, Issue 5 2006Jianfeng Li Abstract Summary: The evolution dynamics of phase separation, coupled with shape deformation of vesicles is described by using dissipative dynamic equations, specifically the time-dependent Ginzburg-Landau (TDGL) equations. In order to improve the numerical stability and thus to efficiently deal with a large deformation of vesicles, a new algorithm, namely the discrete space variation model (DSVM) has been developed for the first time. The algorithm is based on the variation of the discretized free-energy functional, which is constructed in discrete membrane space, in contrast to the commonly used continuous free-energy functional. For the sake of numerical tractability, only the cylindrical vesicles (2D), with two components, are taken into consideration to illustrate the efficiency and validity of new algorithm. The simulation results, based on the DSVM algorithm have been compared with those from both linear analysis and strong segregation theory using the continuous space free-energy functional. It is found that the DSVM algorithm can correctly describe the coupling between the lateral phase-separation on the vesicle membrane and the vesicle shape deformation, both for early and late stages. A flower-like vesicle obtained by DSVM simulation. [source] Partnership Synergy: A Practical Framework for Studying and Strengthening the Collaborative AdvantageTHE MILBANK QUARTERLY, Issue 2 2001Roz D. Lasker The substantial interest and investment in health partnerships in the United States is based on the assumption that collaboration is more effective in achieving health and health system goals than efforts carried out by single agents. A clear conceptualization of the mechanism that accounts for the collaborative advantage, and a way to measure it are needed to test this assumption and to strengthen the capacity of partnerships to realize the full potential of collaboration. The mechanism that gives collaboration its unique advantage is synergy. A framework for operationalizing and assessing partnership synergy, and for identifying its likely determinants, can be used to address critical policy, evaluation, and management issues related to collaboration. [source] A new large animal model for studying and testing treatments of angioproliferative eye diseasesACTA PHYSIOLOGICA, Issue 4 2006Bengt RippeArticle first published online: 3 JUL 200 No abstract is available for this article. [source] The vitamin D receptor gene variant and physical activity predicts fasting glucose levels in healthy young menDIABETIC MEDICINE, Issue 6 2003J. R. Ortlepp Abstract Aims Vitamin D can influence lipolysis and insulin secretion. A common genetic polymorphism of the vitamin D receptor (VDR), which has been found to be associated with bone mineral density, has been reported to be also associated with Type 2 diabetes mellitus (DM). To test the influence of the VDR polymorphism on fasting glucose in healthy young men before the onset of Type 2 DM, we studied a homogeneous population of aircrew members. Methods A total of 1539 individuals were recruited during routine medical qualification for flying duty. Physical activity was assessed in all individuals and categorized into low physical activity (, 3 h per week) and high physical activity (> 3 h per week). The BsmI VDR polymorphism was analysed by polymerase chain reaction. On the day of blood testing the individuals were fasting for at least 8 h overnight. Serum glucose was measured within 60 min after sampling venous blood. Results In young males with low physical activity (n = 752) gene carriers with the VDR genotype BB (n = 137) have significantly (P < 0.001) higher levels of fasting glucose (5.61 ± 0.49 mmol/l) than gene carriers with the genotype Bb (n = 370; 5.44 ± 0.44 mmol/l) or bb (n = 245; 5.38 ± 0.44 mmol/l). Of BB gene carriers, 47% had fasting glucose levels > 5.55 mmol/l compared with 36% of Bb gene carriers and 34% of bb gene carriers (P = 0.018). This effect is absent in gene carriers with high physical activity (n = 787). Conclusions The VDR genotype is associated with altered fasting glucose levels in young men with low physical activity. If this association is confirmed in other populations it might be worthwhile studying the particular benefits of an exercise programme in dependents of the VDR genotype. Diabet. Med. 20, 451,454 (2003) [source] A comparison of changes in dental students' and medical students' approaches to learning during professional trainingEUROPEAN JOURNAL OF DENTAL EDUCATION, Issue 4 2001Robert Lindemann The purposes of this study were 1) to compare the learning approaches of dental students (DS) and medical students (MS) for the Class of 1998 at a single institution at admission and graduation and 2) to determine if their learning approaches changed over the course of their studies. An Approaches to Studying Inventory (ASI) was administered to DS and MS at two times: their first month in school and their last month in school. Means and standard deviations were calculated for three ASI orientations to studying: ,Meaning', ,Reproducing', and ,Achieving'. An additional domain referred to as ,Styles and Pathologies' identified learning problems. In comparison, DS and MS demonstrated a different pattern of learning approaches at matriculation; however, at graduation these differences were less apparent. Over time, DS reported a decreased use, and MS reported an increased use of the Reproducing orientation bringing them closer together. MS also demonstrated an increased use of the Achieving orientation. The Meaning orientation, which indicates a deep approach to learning, was equivalently used by both groups at entry and remained unaltered. [source] Prostitution as a Male Object of Epistemological PainGENDER, WORK & ORGANISATION, Issue 2 2002Hugo Letiche It is not, in the first place, prostitutes' physical and psychological pain that is examined in this article, but the pain encountered in trying to come to terms with the studying of prostitution. Prostitution upsets consciousness' efforts and confuses its epistemes of representation. It reveals issues of (male) avoidance and over-rationalization that apply just as well to how business and organization are (not) studied, as to prostitution. Following Artaud, we examine how, because prostitution is both consciousness (idea, theory, representation) and body (sex, body, the physiology of the brain), it poses the problem of doubling. How can one apprehend both: (i) that one is the physical hyle (materiality) of thought and also (ii) remain aware of the contents of consciousness? Artaud claimed that only in ,cruelty' and the ,scream' could the mind and body be grasped at once. By contrast, Derrida proposes via the subjectile to glide over the space between consciousness and body, trying to acknowledge but not be stymied by the double. Finally, we turn to Irigaray who has accepted doubling and has made it epistemologically productive. [source] How Children and Parents Evaluate the Headache Centre's InterventionHEADACHE, Issue 2 2009Anna Ferrari MD Background., While adult headache patients' satisfaction with treatments has been widely investigated, less attention has been paid to children and adolescent headache patients' opinions and their parents' views. Objective., The aim of our follow-up survey was to analyze the outcomes of the Headache Centre's intervention and the evolution of headache according to patients until the age of 16 and their parents. Methods., We studied all outpatients suffering from episodic primary headache according to International Classification of Headache Disorders 2nd edition criteria, seen for the first time in 2005-2006 at the Headache Centre of the University Hospital of Modena (Italy), and at least one of their parents. The duration of the follow-up ranged from 1 to 3 years. For the purpose of the study, a specific questionnaire was created and administered by a telephone interview. Results., We enrolled 84 patients (38 females, 45%; 46 males, 55%; mean age ± SD: 12.9 ± 2.9 years) with primary headache: migraine without aura 66%, episodic tension-type headache 23%, migraine with aura 11%. At the follow-up, 70% of the patients reported that headache had improved; frequency had decreased significantly more than severity (P = .000, Fisher's exact test), both in those who had followed a prophylactic treatment and in those who had not. A high percentage of the children and parents could precisely indicate trigger factors for headache: especially excessive worrying and studying. The patients reporting an improvement attributed it to pharmacological prophylactic treatment, but also to other factors: first of all, better school results and more happiness than before. Seventy-seven percent of the parents thought that the Headache Centre's intervention had helped them to better understand and manage their children's headache. Conclusions., Children's and adolescents' headache has in most cases a favorable prognosis; the Headache Centre's intervention is considered effective by most parents. We must increase and focus therapeutic efforts addressed to the few patients with worsening headaches in spite of treatment, since these children's/adolescents' headache also is at risk to progress in the adult age. [source] Ceramic Matrix Composites: A Challenge in Space-Propulsion Technology ApplicationsINTERNATIONAL JOURNAL OF APPLIED CERAMIC TECHNOLOGY, Issue 2 2005Stephan Schmidt Various technology programs in Europe are concerned, besides developing reliable and rugged, low-cost, throwaway equipment, with preparing for future reusable propulsion technologies. One of the key roles for realizing reusable engine components is the use of modern and innovative materials. One of the key technologies that concerns various engine manufacturers worldwide is the development of fiber-reinforced ceramics,CMCs (ceramic matrix composites). The advantages for the developers are obvious,the low specific weight, the high specific strength over a large temperature range, and their great damage tolerance compared with monolithic ceramics make this material class extremely interesting as a construction material. Over the past few years, the EADS-ST Company (formerly DASA) has, together with various partners, worked intensively on developing components for hypersonic engines and liquid rocket propulsion systems. In the year 2000, various hot-firing tests with subscale (scale 1:5) and full-scale nozzle extensions were conducted. In this year, a further decisive milestone was achieved in the sector of small thrusters, and long-term tests served to demonstrate the extraordinary stability of the C/SiC material. Besides developing and testing radiation-cooled nozzle components and small-thruster combustion chambers, EADS-ST worked on the preliminary development of actively cooled structures for future reusable propulsion systems. In order to get one step nearer to this objective, the development of a new fiber composite was commenced within the framework of a regionally sponsored program. The objective here is to create multidirectional (3D) textile structures combined with a cost-effective infiltration process. Besides material and process development, the project also encompasses the development of special metal/ceramic and ceramic/ceramic joining techniques as well as studying and verifying nondestructive investigation processes for the purpose of testing components. [source] Self-reported health, self-esteem and social support among young unemployed people: a population-based studyINTERNATIONAL JOURNAL OF SOCIAL WELFARE, Issue 2 2002Lars Axelsson A population-based study was performed in southern Sweden in the autumn of 1998. The aim was to study connections between self-reported health, self-esteem and social support among unemployed (, three months) young people. The sample consisted of 264 unemployed individuals aged 20,25 years, and 528 individuals of the same age, randomly selected from the population register and not registered as unemployed. The response rate was 72%. Defined by means of factor analysis, mental health consisted of the symptoms tearfulness, dysphoria, sleeping disturbance, restlessness, general fatigue and irritability. The unemployed had more mental health problems than young people who were working or studying. Restlessness and dysphoria were significantly over-represented in the unemployed among both sexes. However, good social support seemed to predict mental health. Support from parents was most important, particularly in males. Those with low self-esteem and poor parental support were especially vulnerable. [source] An exploratory study of the perceptions and experiences of further education amongst the young long-term unemployedJOURNAL OF COMMUNITY & APPLIED SOCIAL PSYCHOLOGY, Issue 5 2002Bruce Bolam Abstract The aim of this study was to explore, in depth, the perceptions and experiences of Further Education (FE) amongst the young long-term unemployed. Semi-structured interviews were conducted with 16 long-term unemployed youths of 18,25 years of age divided into three groups: those with no experience of FE; those having recently dropped out of FE; and those currently studying in FE. Grounded theoretical analysis highlighted the importance of both responses to and institutional aspects of unemployment. The impact of unemployment, poor previous educational experience and perceived irrelevance of FE are key barriers to learning. Those that enter FE may drop out as a result of both material and psychosocial factors. Those that stay on commonly emphasize both social support and personal agency in decision-making alongside positive evaluations of FE. In conclusion, limitations of the findings, policy and practical recommendations for successful widening of participation in FE amongst this group are considered. Copyright © 2002 John Wiley & Sons, Ltd. [source] An evaluation of horizontal echo sounding as a method for behavioural studies of 0+ fish in field experimentsJOURNAL OF FISH BIOLOGY, Issue 6 2001P. Romare A 120 kHz echo sounder, with two split-beam transducers, was used horizontally to monitor the behaviour of 0 + roach Rutilus rutilis, from June to August, in field enclosures. 0+ roach outside the vegetated area of the enclosures were registered both as schools and as single swimming fish. Combining echo counting and tracking with direct observation of echograms, an estimate of relative abundance of 0 + roach in the open water volume was obtained also. With this set up, intermediate sized field experiments studying 0 + fish, may be performed during the whole summer season. [source] Direct measurements of the addition and recombination of acrylate radicals: Access to propagation and termination rate constants?JOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 11 2006J. Lalevée Abstract Acrylate radicals produced by the addition of an aminoalkyl radical to five acrylate monomers were directly observed by transient absorption spectroscopy, which allowed us to easily follow their chemical reactivity. It was possible (1) to characterize their absorption in the visible part of the spectrum, (2) to calculate their absorption properties, (3) to determine the energy barriers of the addition through quantum mechanical calculations, (4) to monitor the kinetics of the subsequent addition to another monomer unit, and (5) to follow the recombination of two acrylate radicals. These two latter points could mimic the propagation and termination reactions of polymerization-propagating acrylate radicals. Methacrylate and acrylonitrile radicals were also studied. The obtained results were in good agreement with the propagation rate constants determined by the well-established pulsed laser polymerization techniques. Our method could likely provide rapid access to both the propagation and termination rate constants in suitable systems and appears to be powerful and promising for studying and comparing the reactivities of different acrylate monomer structures. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 3577,3587, 2006 [source] Raman optical activity of an achiral element in a chiral environmentJOURNAL OF RAMAN SPECTROSCOPY, Issue 9 2009Andrew M. Smith Abstract Raman optical activity (ROA) is a relatively new technique used to determine the structure of chiral molecules and is proving useful in the study of biological molecules such as proteins and DNA/RNA. Here, for the first time, we demonstrate the applicability of ROA as a technique to study achiral groups in chiral environments, detecting the induced chirality of N -(fluorenyl-9-methoxycarbonyl) (Fmoc) in a chiral self-assembled structure of Fmoc-dipeptides. This technique is therefore of interest to those studying self-assembled systems that adopt a chiral structure. Copyright © 2009 John Wiley & Sons, Ltd. [source] Circulation of Books in the Medieval Franciscan Order: Attitude, Methods, and CriticsJOURNAL OF RELIGIOUS HISTORY, Issue 2 2004Neslihan Senocak One of the significant advantages that the Franciscan friars had over their secular colleagues in the medieval intellectual domain was easy access to books. Not only did the order establish well-endowed libraries, but also facilitated the circulation of books among the friars who were involved in preaching and studying. The notes on Franciscan manuscripts indicating a loan or a borrower, the library inventories, together with the constitutional evidence reveal some interesting practices in this respect. Although it was the nature of scholastic teaching that necessitated private use, and hence the assignment of books, the practice nevertheless remained unpopular with the faction in the order known as the Spirituals. They saw it as the cause of the multiplication of books, thereby a serious breach in the order's creed of evangelical poverty. The circulation of books nevertheless continued with increasing momentum and was one of the issues responsible for the schism in the order. [source] Web search strategies and approaches to studyingJOURNAL OF THE AMERICAN SOCIETY FOR INFORMATION SCIENCE AND TECHNOLOGY, Issue 6 2003Nigel Ford This paper reports results from a project, which sought to investigate the relationship between study approaches and Web-based information seeking. Factor analyses were applied to data from over 500 queries submitting in response to three different search tasks to identify clusters of variables associated with three Web-based search strategies: Boolean, best-match, and combined. A consistent pattern emerged across the nine analyses in relation to a number of study approach variables. Boolean searching was consistently associated with a reproductive (as opposed to meaning-oriented) approach, anxiety (in the form of fear of failure), and high levels of active interest. Best-match was associated with the converse of all these measures. Combined searching was differentiated from both Boolean and best-match by being associated with poor time management. There was also some evidence of changes in strategy in relation to task complexity. A model is introduced which seeks to explain these results. This project was exploratory in nature, and the pattern of findings are proposed as prima facie evidence to support the notion that study approaches can influence choice of search strategies. The results are considered essentially as hypotheses for further systematic study, for which suggestions are made. [source] Hepatitis B virus DNA levels, precore mutations, genotypes and histological activity in chronic hepatitis BJOURNAL OF VIRAL HEPATITIS, Issue 4 2000Lindh The present study aimed to clarify how viraemia levels reflect the clinical stages of chronic hepatitis B virus (HBV) infection, in particular studying whether ,healthy carriers' can be identified by analysing HBV DNA levels with a highly sensitive quantitative assay. Histology activity index (HAI), alanine aminotransferase (ALT) level, genotype and precore mutations were compared with the HBV DNA level, as measured using the Amplicor HBV Monitor assay in a prospective study. In 124 hepatitis B e antigen-negative (HBeAg,) patients, the majority with mild liver disease, log HBV DNA levels showed a Gaussian distribution around a geometric mean of 33 000 genome copies ml,1, and increasing HBV DNA level was associated with significantly higher inflammation (HAIinfl) and fibrosis (HAIfibr) scores and higher ALTi (ALT ÷ the upper reference value). Severe inflammation (HAIinfl , 7) was seen in 83% (five of six), 36% (eight of 22) and 3% (one of 37) of HBeAg, patients with HBV DNA > 107, > 2 × 105 and < 104 copies ml,1, respectively. In severe HBeAg, hepatitis, patients with precore wild-type infection had lower HBV DNA levels than those with precore mutants. In 36 HBeAg-positive (HBeAg+) patients, no correlation between HBV DNA level and liver damage was seen. Ninety-six per cent of HBeAg, patients with ALTi < 0.5 had HAIinfl , 3. In HBeAg, carriers with ALTi 0.5,1.0, the relative risk for severe inflammation, comparing HBV DNA > 2 × 105 copies ml,1vs < 2 × 105 copies ml,1, was 14.7. In conclusion, in HBeAg, carriers, HBV DNA < 104 copies ml,1 or ALTi < 0.5 indicates mild inflammation, while > 2 × 105 copies ml,1 of HBV DNA may justify further investigations. Precore status may be relevant for the interpretation of viraemia. [source] Low magnetic fields behavior of photon echo in LuLiF4:Er3+LASER PHYSICS LETTERS, Issue 9 2006V. N. Lisin Abstract It is reported about the first observation and studying of the photon echo in LuLiF4:Er3+. The energy transition is 4I15/2 , 4F9/2 (, = 6536 Ĺ). The density of ErF3 is 0.025 wt%. The operation temperature is 1.9 K. Measurements were spent at low (up to 1200 Oe) and even zero external magnetic fields. It was studied a behavior of the photon echo intensity versus the magnetic field magnitude and direction about the crystal axis C and versus the laser pulse separation t12. It was observed an exponential growth and then, after some plateau, an exponential decreasing of the photon echo intensity as a function of magnetic field with increasing of the magnetic field from zero value. The parameters describing the exponential growth and decreasing are not depended on direction of magnetic field. Value of a magnetic field at which the echo intensity accepts the maximum, and quantity of this maximum decrease with increased the pulse separation t12 and the angle , between the magnetic field and crystal axis. The echo intensity exponentially decreases with increased , . The parameter describing the exponential decreasing is not depended on the magnitude of the field. The echo intensity as a function of pulse separation shows exponential decay. The phase relaxation time is depended on the magnitude and direction of the magnetic field. T2 is equal to 202 ± 16 ns at zero magnetic field. Phenomenological formula is suggested, which qualitatively presents the mentioned dependencies. Polarization properties of the backward photon echo in this crystal are studied also. (© 2006 by Astro, Ltd. Published exclusively by WILEY-VCH Verlag GmbH & Co. KGaA) [source] Effect of the Amount of Hours Spent Studying on the Prevalence of Overactive Bladder in College WomenLUTS, Issue 2 2010Dong Gil SHIN Objectives: We conducted a questionnaire survey to access whether the amount of hours spent studying has an effect on the prevalence of OAB in college women. Methods: A total of 126 (63%; mean: 23.2 years) of 200 women participants completed the questionnaire. They were divided into two groups: group A (weekly studying hour >40 h) consisted of medical female students and group B (weekly studying hour <25 h) consisted of French literature woman students. The factors related to OAB were analyzed by the chi-squared test. Results: Of 126 respondents, the prevalence of OAB was prevalent in 38 (30.2%) women. There was significant difference in prevalence between the two groups: 7.0% for group A and 42.2% for group B. In group B, OAB prevalence was 66.7% for ,2 h, 41.2% for 2,,4 h, 46.5% for 4,,6 h, and >6 h was 23.5%. This survey showed that there is no relationship between the amount of hours spent studying and OAB. Conclusion: Although the amount of hours spent studying had no association with OAB in college women, OAB prevalence showed a decreasing pattern as the quantity of studying hour increases. Consequently, it is thought that the attitude toward study has more association with OAB than the quantity of studying hours. [source] Metallic dental materials in patient's oral cavity acting as electrodes of electrochemical cellsMATERIALS AND CORROSION/WERKSTOFFE UND KORROSION, Issue 7 2004W. Opydo Abstract The work was aimed at studying of standard potentials of commonly used metallic dental materials and determining of the effect of saliva conductivity and reaction on value of the potentials. The following materials have been examined: gold alloy (a material used for crowns and bridgeworks), chromium-cobalt alloy (for frameworks in removable partial dentures), and silver amalgams (used for fillings) manufactured by three different companies. Taking into account that mucosa makes one of the electrodes existing in oral cavity the rest potentials of mucosa have been in vivo measured in several patients. Their values, converted with respect to NHE, oscillated within the range from + 0.31 V to + 0.47 V. Among metallic dental materials examined in the experiment maximal standard potential was found for the gold alloy, further materials having lower potentials, in decreasing order, were chromium-cobalt alloy, and the amalgams Amalcap Plus, ANA 2000 and Septalloy. Significant differences between standard potentials of examined materials and mucosa indicate spontaneous formation of galvanic cells of electromotive force reaching even about 0.6 V. [source] | |||||||||||||||||||||||||||||||