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Selected AbstractsNonlinear determinism in river flow: prediction as a possible indicatorEARTH SURFACE PROCESSES AND LANDFORMS, Issue 7 2007Bellie SivakumarArticle first published online: 6 DEC 200 Abstract Whether or not river flow exhibits nonlinear determinism remains an unresolved question. While studies on the use of nonlinear deterministic methods for modeling and prediction of river flow series are on the rise and the outcomes are encouraging, suspicions and criticisms of such studies continue to exist as well. An important reason for this situation is that the correlation dimension method, used as a nonlinear determinism identification tool in most of those studies, may possess certain limitations when applied to real river flow series, which are always finite and often short and also contaminated with noise (e.g. measurement error). In view of this, the present study addresses the issue of nonlinear determinism in river flow series using prediction as a possible indicator. This is done by (1) reviewing studies that have employed nonlinear deterministic methods (coupling phase-space reconstruction and local approximation techniques) for river flow predictions and (2) identifying nonlinear determinism (or linear stochasticity) based on the level of prediction accuracy in general, and on the prediction accuracy against the phase-space reconstruction parameters in particular (termed as the ,inverse approach'). The results not only provide possible indications to the presence of nonlinear determinism in the river flow series studied, but also support, both qualitatively and quantitatively, the low correlation dimensions reported for such. Therefore, nonlinear deterministic methods are a viable complement to linear stochastic ones for studying river flow dynamics, if sufficient caution is exercised in their applications and in interpreting the outcomes. Copyright © 2006 John Wiley & Sons, Ltd. [source] Antiepileptic drugs in children in developing countries: Research and treatment guideline needsEPILEPSIA, Issue 11 2009Mina Farkhondeh Summary Epilepsy is the most common neurologic disorder in childhood. Effective interventions are available for treatment; however, the treatment gap in children is more than 80% in many developing countries. An important reason for this huge treatment gap is limited access to antiepileptic drugs (AEDs). This article discusses the reasons for such a treatment gap, and possible ways forward in improving care of children with epilepsy worldwide. [source] Experimental and Clinical Evidence for Loss of Effect (Tolerance) during Prolonged Treatment with Antiepileptic DrugsEPILEPSIA, Issue 8 2006Wolfgang Löscher Summary:, Development of tolerance (i.e., the reduction in response to a drug after repeated administration) is an adaptive response of the body to prolonged exposure to the drug, and tolerance to antiepileptic drugs (AEDs) is no exception. Tolerance develops to some drug effects much more rapidly than to others. The extent of tolerance depends on the drug and individual (genetic?) factors. Tolerance may lead to attenuation of side effects but also to loss of efficacy of AEDs and is reversible after discontinuation of drug treatment. Different experimental approaches are used to study tolerance in laboratory animals. Development of tolerance depends on the experimental model, drug, drug dosage, and duration of treatment, so that a battery of experimental protocols is needed to evaluate fully whether tolerance to effect occurs. Two major types of tolerance are known. Pharmacokinetic (metabolic) tolerance, due to induction of AED-metabolizing enzymes has been shown for most first-generation AEDs, and is easy to overcome by increasing dosage. Pharmacodynamic (functional) tolerance is due to "adaptation" of AED targets (e.g., by loss of receptor sensitivity) and has been shown experimentally for all AEDs that lose activity during prolonged treatment. Functional tolerance may lead to complete loss of AED activity and cross-tolerance to other AEDs. Convincing experimental evidence indicates that almost all first-, second-, and third-generation AEDs lose their antiepileptic activity during prolonged treatment, although to a different extent. Because of diverse confounding factors, detecting tolerance in patients with epilepsy is more difficult but can be done with careful assessment of decline during long-term individual patient response. After excluding confounding factors, tolerance to antiepileptic effect for most modern and old AEDs can be shown in small subgroups of responders by assessing individual or group response. Development of tolerance to the antiepileptic activity of an AED may be an important reason for failure of drug treatment. Knowledge of tolerance to AED effects as a mechanism of drug resistance in previous responders is important for patients, physicians, and scientists. [source] Ecophysiological controls over the net ecosystem exchange of mountain spruce stand.GLOBAL CHANGE BIOLOGY, Issue 1 2007Comparison of the response in direct vs. diffuse solar radiation Abstract Cloud cover increases the proportion of diffuse radiation reaching the Earth's surface and affects many microclimatic factors such as temperature, vapour pressure deficit and precipitation. We compared the relative efficiencies of canopy photosynthesis to diffuse and direct photosynthetic photon flux density (PPFD) for a Norway spruce forest (25-year-old, leaf area index 11 m2 m,2) during two successive 7-day periods in August. The comparison was based on the response of net ecosystem exchange (NEE) of CO2 to PPFD. NEE and stomatal conductance at the canopy level (Gcanopy) was estimated from half-hourly eddy-covariance measurements of CO2 and H2O fluxes. In addition, daily courses of CO2 assimilation rate (AN) and stomatal conductance (Gs) at shoot level were measured using a gas-exchange technique applied to branches of trees. The extent of spectral changes in incident solar radiation was assessed using a spectroradiometer. We found significantly higher NEE (up to 150%) during the cloudy periods compared with the sunny periods at corresponding PPFDs. Prevailing diffuse radiation under the cloudy days resulted in a significantly lower compensation irradiance (by ca. 50% and 70%), while apparent quantum yield was slightly higher (by ca. 7%) at canopy level and significantly higher (by ca. 530%) in sun-acclimated shoots. The main reasons for these differences appear to be (1) more favourable microclimatic conditions during cloudy periods, (2) stimulation of photochemical reactions and stomatal opening via an increase of blue/red light ratio, and (3) increased penetration of light into the canopy and thus a more equitable distribution of light between leaves. Our analyses identified the most important reason of enhanced NEE under cloudy sky conditions to be the effective penetration of diffuse radiation to lower depths of the canopy. This subsequently led to the significantly higher solar equivalent leaf area compared with the direct radiation. Most of the leaves in such dense canopy are in deep shade, with marginal or negative carbon balances during sunny days. These findings show that the energy of diffuse, compared with direct, solar radiation is used more efficiently in assimilation processes at both leaf and canopy levels. [source] Migraine Headache Recurrence: Relationship to Clinical, Pharmacological, and Pharmacokinetic Properties of TriptansHEADACHE, Issue 4 2003Gilles Géraud MD Background and Objectives.,Triptan use is associated with headache recurrence, and this has been cited as an important reason for patient dissatisfaction with the treatment. The mechanism by which recurrence occurs is not clear, and the incidence of recurrence varies with the triptan used. In order to explore the pharmacological and physiological interaction of triptans and migraine headache recurrence further, some specific clinical, pharmacological, and pharmacokinetic factors that might influence migraine recurrence were evaluated in a review of the major efficacy data for the drugs in the triptan class. These factors were 5-HT1B and 5-HT1D receptor activities, the pharmacokinetic elimination half-life of each triptan, and the clinical efficacy of each compound, determined by the proportion of patients with headache relief and the therapeutic gain over placebo. Methods.,Clinical data were derived from 31 triptan, placebo-controlled, major efficacy studies used in a previous meta-analysis. The mean recurrence rate, mean headache response, and therapeutic gain were calculated using the results from the individual clinical studies. Mean headache response and therapeutic gain were calculated at the time point used to define recurrence in each study. Data for binding affinity and potency were taken from a direct-comparison in vitro pharmacology study, and the elimination half-life quoted in the data sheet for each triptan was used. Rank correlation with recurrence rate was performed for each of the test parameters. Results.,Mean headache recurrence rates ranged from 17% for frovatriptan 2.5 mg to 40% for rizatriptan. Elimination half-life and recurrence were inversely correlated (r = ,1.0, P = .0016). There was also a significant inverse correlation between 5-HT1B receptor potency and recurrence (r = ,0.68, P = .034), but 5-HT1D receptor potency was not correlated with recurrence (r = ,0.20, P = .54). In addition, the binding affinities for the 5-HT1B and 5-HT1D receptors were not correlated to headache recurrence. Importantly, it also was demonstrated that initial clinical efficacy was not correlated to headache recurrence. The correlation coefficient for headache response was 0.18 (P = .53) and for therapeutic gain, ,0.11 (P = .71). Conclusion.,The incidence of migraine headache recurrence varies between drugs in the triptan class. Migraine recurrence does not appear to be related to initial clinical efficacy, but is influenced by the pharmacological and pharmacokinetic properties of the individual triptans. The triptans with longer half-lives and greater 5-HT1B receptor potency had the lowest rates of headache recurrence. [source] Evidence for prolonged clinical benefit from initial combination antiretroviral therapy: Delta extended follow-upHIV MEDICINE, Issue 3 2001Delta Coordinating Committee Background The findings from therapeutic trials in HIV infection with surrogate endpoints based on laboratory markers are only partially relevant for clinical decisions on treatment. Although the collection of clinical follow-up data from such a trial would be relatively straightforward, this rarely occurs. An important reason for this may be the perception that such data have little value because the number of participants remaining on their original allocated therapy has usually fallen substantially. Methods Delta was an international, multicentre trial in which 3207 HIV infected individuals were randomly allocated to treatment with zidovudine (ZDV) alone, ZDV combined with didanosine (ddI) or ZDV combined with zalcitabine (ddC). Although the trial closed in September 1995, information on vital status, AIDS events, treatment changes and CD4 counts was still collected every 12 months until at least March 1997. This has allowed analyses of the longer term clinical effect of treatment. Results The median follow-up to date of death or last known vital status was 43 months (10th percentile 18 months; 90th percentile 55 months). The proportion of participants remaining on their allocated treatment fell steadily over time; by 4 years after trial entry, 3% remained on ZDV, 20% on ZDV + ddI and 21% on ZDV + ddC. Changes mainly involved the stopping, addition or switching of a nucleoside reverse transcriptase inhibitor (NRTIs). There was little use of protease inhibitors (PIs) or non-nucleoside reverse transcriptase inhibitors (NNRTIs) before the third year of the trial. Between the third and fourth years, regimens included a drug from one of these classes for approximately 17% of person-time in all treatment groups. Relative to ZDV monotherapy, the beneficial effects of combination therapy on mortality and disease progression rates increased significantly with time since randomization. The maximum effects on mortality were observed between 2 and 3 years, with a 48% reduction for ZDV + ddI and a 26% reduction for ZDV + ddC. These rates were observed when the original allocated treatment was received 42% and 47% of the time in the ZDV + ddI and ZDV + ddC groups, respectively. The mean CD4 count remained significantly higher (approximately 50 cells/,L) in the combination therapy groups 4 years after randomization, suggesting a projection of a clinical benefit beyond this time point. Conclusions The sustained clinical effect of the initial allocation to combination therapy, particularly ZDV + ddI, was remarkable in light of the convergence of drug regimens actually received across the three treatment groups. Interpretation of this finding is not straightforward. One of the possible explanations is that the effectiveness of ddI and ddC is diminished if first used later in infection or with greater prior exposure to ZDV, although the data do not clearly support either hypothesis. This analysis highlights the value of long-term clinical follow-up of therapeutic trials in HIV infection, which should be considered in the planning of all new studies. [source] Pharmaceutical industry-sponsored meetings: good value or just a free meal?INTERNAL MEDICINE JOURNAL, Issue 8 2001S. L. Carney Abstract Although the role of the pharmaceutical industry in continuing medical education (CME) has been debated for many years, industry CME funding continues to increase. Because of concern about the educational quality of industry CME, the Hunter Postgraduate Medical Institute (HPMI), an independent Newcastle and Hunter Valley CME provider, evaluated the use and quality of industry CME as reported by rural and urban general practitioners, physicians and psychiatrists. Furthermore, clinicians were asked if they supported increased industry-funded independent CME. Sixty-two per cent of general practitioners and 71% of psychiatrists attended at least three industry-organized meetings each year, compared with 24% of physicians. Twenty-five per cent of general practitioners attended five or more such meetings. Industry meetings were judged to be of good to excellent quality by 81% of generalists, 79% of physicians and 87% of psychiatrists. All clinical groups ranked the topic and then speaker as the most important reason for attending, with CME points, venue and the sponsor ranked lowest. Eighty to 90% of doctors supported a greater role of industry-funded independent CME. Despite the absence of current data on the use and perceived benefits of industry CME, these preliminary results suggest that industry CME is playing an increasingly important role in clinician education. However, many clinicians and industry representatives support a greater role by independent postgraduate organizations in industry-sponsored CME. (Intern Med J 2001; 31: 488,491) [source] Comment on ,The Eviction of Critical Perspectives from Gentrification Research'INTERNATIONAL JOURNAL OF URBAN AND REGIONAL RESEARCH, Issue 1 2008LANCE FREEMAN Abstract 'The eviction of critical perspectives from gentrification research' offers the premise that scholars are becoming less critical of gentrification and that this trend is detrimental to those most vulnerable to gentrification. This argument falls short on a number of grounds. First, the article does not persuasively show that the scholarly literature on gentrification has indeed become less critical. More significantly, Slater does not consider perhaps the most important reason that gentrification can be accurately described in both critical and less than critical terms , gentrification's impacts are multifaceted, affecting different people differently and even the same individuals in different ways. Finally, those most threatened by gentrification are likely to need a combination of resistance and persuasion to blunt the ill effects of gentrification. Slater's call for more critical approaches may inspire some to resist, but will do little to persuade the larger society to take their concerns seriously. Given that those most threatened by gentrification are among the least powerful, their cause will most benefit from a combination of literature that inspires resistance as well as literature that persuades others that gentrification is truly a predicament. Therefore, literature that not merely criticizes gentrification but offers a rationale for blunting its detrimental effects is needed as well. Résumé L'article intitulé The eviction of critical perspectives from gentrification research pose en principe que les chercheurs se font moins critiques sur la ,gentrification' et que cette tendance porte préjudice aux plus vulnérables face à ce phénomène. Cet argument ne tient pas pour plusieurs raisons. D'abord, il n'est pas montré de manière probante que la littérature académique sur la ,gentrification' soit vraiment devenue moins critique. De façon plus marquante, Slater n'étudie pas la raison, peut-être la plus importante, pour laquelle la ,gentrification' peut être décrit avec exactitude en termes à la fois critiques et moins critiques : en effet, ses impacts revêtent plusieurs aspects, affectant différemment les populations différentes, voire les mêmes populations. Enfin, les plus menacés par la ,gentrification' ont sans doute besoin d'un mélange de résistance et de persuasion pour atténuer les effets négatifs du processus. L'appel de Slater à des approches plus critiques peut susciter la résistance chez certains, mais va difficilement convaincre la société de traiter sérieusement le problème. Etant donné que les plus menacés font partie des moins puissants, leur cause bénéficiera surtout d'une combinaison de publications inspirant la résistance et de textes capables de convaincre de toute la complexité de la situation liée à la ,gentrification'. En conséquence, une littérature qui ne se contente pas de critiquer la ,gentrification', mais qui propose un raisonnement pour en atténuer les effets néfastes, a tout autant d'utilité. [source] A comparison of modern data analysis methods for X-ray and neutron specular reflectivity dataJOURNAL OF APPLIED CRYSTALLOGRAPHY, Issue 5 2007A. Van Der Lee Data analysis methods for specular X-ray or neutron reflectivity are compared. The methods that have been developed over the years can be classified into different types. The so-called classical methods are based on Parrat's or Abelès' formalism and rely on minimization using more or less evolved Levenberg,Marquardt or simplex routines. A second class uses the same formalism, but optimization is carried out using simulated annealing or genetic algorithms. A third class uses alternative expressions for the reflectivity, such as the Born approximation or distorted Born approximation. This makes it easier to invert the specular data directly, coupled or not with classical least-squares or iterative methods using over-relaxation or charge-flipping techniques. A fourth class uses mathematical methods founded in scattering theory to determine the phase of the scattered waves, but has to be coupled in certain cases with (magnetic) reference layers. The strengths and weaknesses of a number of these methods are evaluated using simulated and experimental data. It is shown that genetic algorithms are by far superior to traditional and advanced least-squares methods, but that they fail when the layers are less well defined. In the latter case, the methods from the third or fourth class are the better choice, because they permit at least a first estimate of the density profile to be obtained that can be refined using the classical methods of the first class. It is also shown that different analysis programs may calculate different reflectivities for a similar chemical system. One reason for this is that the representation of the layers is either described by chemical composition or by scattering length or electronic densities, between which the conversion of the absorptive part is not straightforward. A second important reason is that routines that describe the convolution with the instrumental resolution function are not identical. [source] Friction and wear properties of NBR/PVC compositesJOURNAL OF APPLIED POLYMER SCIENCE, Issue 4 2007Xinwu Huang Abstract Acrylonitrial butadiene rubber (NBR)/Polyvinyl chloride (PVC) composites with different PVC content were prepared. The effect of PVC content on the mechanical strength and tribological properties of the NBR/PVC composites was investigated. The morphologies of the worn traces and debris of NBR/PVC composites and worn traces of mating ball were observed using a scanning electron microscope (SEM). It was found that the friction and wear of NBR/PVC was lower than that of NBR without PVC. The NBR/PVC composite with 30% PVC content showed the best synthetic mechanical and tribological properties. The inferior elastic properties and the lesser deformation under the applied load of composites with PVC resulted in hysteric force and adhesion force decrease, which leading to a lower friction and wear of NBR/PVC composites. The frictional failure unit of NBR70/PVC30 composite being smaller should be an important reason of the wear of the composite being lowest. The lubricating effect of PVC played an important role in decreasing the friction coefficient and wear of NBR/PVC composites. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007 [source] Practice, power and meaning: frameworks for studying organizational culture in multi-agency rural development projectsJOURNAL OF INTERNATIONAL DEVELOPMENT, Issue 5 2003David Lewis Culture has received increasing attention in critical development studies, though the notion that there are important cultural differences within and between development organizations has received less consideration. This paper elaborates elements of a framework for studying organizational culture in multi-agency development projects. It draws on selected writings in anthropology and in organizational theory and suggests that these two bodies of literature can be usefully brought together, as well as on insights from ongoing fieldwork in Bangladesh, Burkina Faso and Peru. At the centre of this framework is the analysis of context, practice and power. Where development projects involve multiple organizations (such as donors, government agencies, non-governmental organizations and grassroots groups) an analysis of cultures both within and between organizational actors can help explain important aspects of project performance. The paper argues that organizational culture is constantly being produced within projects, sometimes tending towards integration, often towards fragmentation. This fragmentation, indicative of the range of cultures within development organizations, is an important reason why some projects fail, and why ideas stated in project documents are often not realized, especially in the case of the newer and more contentious objectives such as ,empowerment'. © 2003 John Wiley & Sons, Ltd. [source] A comparison of cohabiting relationships among older and younger adultsJOURNAL OF MARRIAGE AND FAMILY, Issue 2 2005Valarie King This study explores how cohabitation differs for older and younger adults, drawing on data from 966 cohabitors in each of the first 2 waves of the National Survey of Families and Households. Older cohabitors report significantly higher levels of relationship quality and stability than younger cohabitors, although they are less likely to have plans to marry their partners. Few differences were found in the reasons to cohabit, although assessing compatibility is a more important reason for younger cohabitors. Findings suggest that older cohabitors are more likely to view their relationship as an alternative to marriage, whereas younger cohabitors are more likely to view their relationship as a prelude to it. [source] Cationic, water-soluble, fluorene-containing poly(arylene ethynylene)s: Effects of water solubility on aggregation, photoluminescence efficiency, and amplified fluorescence quenching in aqueous solutionsJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 19 2006Yan-Qin Huang Abstract Three novel fluorene-containing poly(arylene ethynylene)s with amino-functionalized side groups were synthesized through the Sonogashira reaction. They were poly{9,9-bis[6,-(N,N -diethylamino)hexyl]-2,7-fluorenylene ethynylene}- alt - co -{2,5-bis[3,-(N,N -diethylamino)-1,-oxapropyl]-1,4-phenylene} (P1), poly{9,9-bis[6,-(N,N -diethylamino)hexyl]-2,7-fluorenylene ethynylene} (P2), and poly({9,9-bis[6,-(N,N -diethylamino)hexyl]-2,7-fluorenylene ethynylene}- alt - co -(1,4-phenylene)) (P3). Through the postquaternization treatment of P1,P3 with methyl iodide, we obtained their cationic water-soluble conjugated polyelectrolytes (WSCPs): P1,,P3,. The water solubility was gradually improved from P3, to P1, with increasing contents of hydrophilic side chains. After examining the ultraviolet,visible absorption and photoluminescence (PL) spectra, fluorescence lifetimes, and dynamic light scattering data, we propose that with the reduction of the water solubility from P1, to P3,, they exhibited a gradually increased degree of aggregation in H2O. The PL quantum yields of P1,,P3, in H2O displayed a decreasing tendency consistent with the increased degree of aggregation, suggesting that the pronounced degree of aggregation was an important reason for the low PL quantum yields of WSCPs in H2O. Two structurally analogous water-soluble trimers of P2, and P3,, model compounds 2,7-bis(9,,9,-bis{6,-[(N,N -diethyl)- N -methylammonium] hexyl}-2,-fluorenylethynyl)-9,9-bis{6,-[(N,N -diethyl)- N -methylammonium]hexyl}fluorene hexaiodide and 1,4-bis(9,,9,-bis{6,-[(N,N -diethyl)- N -methylammonium]hexyl}-2,-fluorenylethynyl)benzene tetraiodide, were synthesized. The amplified fluorescence quenching of these WSCPs by Fe(CN)64, in H2O was studied by comparison with a corresponding analogous trimer. The effects of aggregation on the fluorescence quenching may be two-edged in these cases. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 5778,5794, 2006 [source] The Liquidity Demand for Corporate Property InsuranceJOURNAL OF RISK AND INSURANCE, Issue 2 2006Arthur Hau This article suggests that liquidity may be an important reason for a corporation to purchase property insurance. A model of a risk-neutral producer facing an endogenously determined risk of property damage under an output contract that penalizes underproduction is formulated to exemplify such a real need of liquidity. Under the output contract, the producer may purchase full unfavorable property insurance even when postloss financing is available. Surprisingly, the conclusion may still hold when the cost of postloss financing equals that of long-term capital, provided that the rate of underproduction penalty is sufficiently high. Similar conclusions apply when postloss financing is replaced by planned internal reserve (self-insurance) that may be invested in the short run at an interest rate that is lower than the long-term cost of capital. When the capital market is perfect, however, the holding of planned internal reserve eliminates the purchase of actuarially unfavorable property insurance. [source] Ischaemic heart disease in the dog: a review of 65 casesJOURNAL OF SMALL ANIMAL PRACTICE, Issue 3 2000T. Falk Sixty-five dogs are reviewed with histopathologically confirmed intramural arteriosclerosis. Clinical data (clinical signs, electrocardiographic findings and ultrasound parameters) on these animals were collected from nine small animal clinics in Sweden: 16 dogs had died suddenly, with few or no previous clinical signs; 13 dogs died or were euthanased during or shortly after general anaesthesia or sedation; 30 dogs developed acute (14) or chronic (16) congestive heart failure; and six dogs died or were euthanased for causes unrelated to cardiac disease. Electrocardiography of 23 of the dogs revealed several types of arrhythmias, with atrial fibrillation and sinus tachycardia being most commonly detected. Ultrasonographic examinations of 24 dogs found a relatively high number (19) with decreased indices of contractility. Dogs that had died suddenly and in relation to general anaesthesia or sedation had a higher incidence (25 of 29) of purely arteriosclerotic changes in the myocardial vessels, whereas just over half the dogs with congestive heart failure (16 of 30) had other concomitant heart lesions (in most cases endocardiosis). The incidence of myocardial infarcts was high (51 of 65 cases). It is postulated that arteriosclerosis in the dog may be an important reason for sudden death and death during general anaesthesia. Coronary arterial disease should also be a consideration in the clinical evaluation of dilated cardiomyopathy and may contribute to the decreased myocardial contractility when it is present in dogs with mitral regurgitation. [source] Impact of experience on maintenance skillsJOURNAL OF SOFTWARE MAINTENANCE AND EVOLUTION: RESEARCH AND PRACTICE, Issue 2 2002Magne Jørgensen Abstract This study reports results from an empirical study of 54 software maintainers in the software maintenance department of a Norwegian company. The study addresses the relationship between amount of experience and maintenance skills. The findings were, amongst others, as follows. (1) While there may have been a reduction in the frequency of major unexpected problems from tasks solved by very inexperienced to medium experienced maintainers, additional years of general software maintenance experience did not lead to further reduction. More application specific experience, however, further reduced the frequency of major unexpected problems. (2) The most experienced maintainers did not predict maintenance problems better than maintainers with little or medium experience. (3) A simple one-variable model outperformed the maintainers' predictions of maintenance problems, i.e. the average prediction performance of the maintainers seems poor. An important reason for the weak correlation between length of experience and ability to predict maintenance problems may be the lack of meaningful feedback on the predictions. Copyright © 2002 John Wiley & Sons, Ltd. [source] A Study of Reasons for Participation in Continuing Professional Education in the U.S. Nuclear Power IndustryPERFORMANCE IMPROVEMENT QUARTERLY, Issue 3 2003Randy B. McCamey ABSTRACT The need for workers in the U.S. nuclear power industry to continually update their knowledge, skills, and abilities is critical to the safe and reliable operation of the country's nuclear power facilities. To improve their skills, knowledge, and abilities, many professionals in the nuclear power industry participate in continuing professional education (CPE). This study investigates participation in CPE using the Participation Reasons Scale (Grotel-ueschen, 1985), a 30-item self-report instrument that measures five dimensions or reasons for participation in continuing professional education. Professional Development ranked as the most important reason for participating in continuing professional education. Identity and Commitment ranked as the least important reason for participating. All reasons for voluntary participation were found to be significantly different (higher) than corresponding compulsory reasons for participation in CPE. [source] Reasons U.S. Women Have Abortions: Quantitative and Qualitative PerspectivesPERSPECTIVES ON SEXUAL AND REPRODUCTIVE HEALTH, Issue 3 2005B. Lawrence CONTEXT: Understanding women's reasons for having abortions can inform public debate and policy regarding abortion and unwanted pregnancy. Demographic changes over the last two decades highlight the need for a reassessment of why women decide to have abortions. METHODS: In 2004, a structured survey was completed by 1,209 abortion patients at 11 large providers, and in-depth interviews were conducted with 38 women at four sites. Bivariate analyses examined differences in the reasons for abortion across subgroups, and multivariate logistic regression models assessed associations between respondent characteristics and reported reasons. RESULTS: The reasons most frequently cited were that having a child would interfere with a woman's education, work or ability to care for dependents (74%); that she could not afford a baby now (73%); and that she did not want to be a single mother or was having relationship problems (48%). Nearly four in 10 women said they had completed their childbearing, and almost one-third were not ready to have a child. Fewer than 1% said their parents' or partners' desire for them to have an abortion was the most important reason. Younger women often reported that they were unprepared for the transition to motherhood, while older women regularly cited their responsibility to dependents. CONCLUSIONS: The decision to have an abortion is typically motivated by multiple, diverse and interrelated reasons. The themes of responsibility to others and resource limitations, such as financial constraints and lack of partner support, recurred throughout the study. [source] A nonlinear theoretical model for prediction of mechanical behavior of particulate composites and experimental verification of the model predictionsPOLYMER COMPOSITES, Issue 7 2010A. Ramazani S.A. A model for prediction the stress-strain behavior of particulate composite over wide ranges of filler concentration and composite deformation has been developed through combination of Anderson's and Yilmizer's model. The constitutive equations are extracted from first law of thermodynamic and nonlinear dilatational effects which are produced by filler-matrix debonding process. In addition to nonlinear behavior that has been resulted by filler-matrix debonding and was presented by Yilmizer, the formation and growing of void or cavitations has been also introduced in this model, whereas Anderson's model, most important reason for deviation of linear behavior is filler-matrix debonding and has been indicated by change of modulus. Model predictions for effects of the filler concentration and its particle size and particle size distribution for some matrix-filler systems are compared with related experimental data from literature and some investigated systems in this work. An excellent agreement even better than prediction of Anderson's model between experimental data and model predictions can be observed in most cases especially for some concentrated systems. POLYM. COMPOS., 31:1150,1155, 2010. © 2009 Society of Plastics Engineers [source] All in the family: Evaluation of the process and content of sisters' communication about BRCA1 and BRCA2 genetic test results,AMERICAN JOURNAL OF MEDICAL GENETICS, Issue 2 2002Chanita Hughes Abstract Despite the potential importance of family communication, little is known about the process and content of communicating BRCA1/2 test results to relatives. The objectives of this observational study were to describe the process and content of communicating BRCA1/2 test results to sisters, and to evaluate whether the proband's carrier status influenced communication outcomes. Participants were 43 women who were the first family member to have genetic testing (probands). Probands reported on communication outcomes for 81 sisters. Process and content variables were evaluated 1-month after receipt of BRCA1/2 test results using the Family Communication Questionnaire (FCQ). Overall, BRCA1/2 test results were communicated to 85% of sisters, and carriers communicated their results to significantly more sisters compared to uninformative (96% vs. 76%, FET,=,0.02). The most important reason for communicating results was to provide genetic risk information; however, compared to uninformatives, carriers communicated their results to significantly more sisters to obtain emotional support (74%) and to get advice about medical decisions (42%) (FET,=,0.001). Carriers also discussed the possibility of discrimination and recommendations for cancer management with significantly more sisters. Among sisters to whom BRCA1/2 test results were not communicated, the most important reason for not sharing test results was because of emotionally distant relationships. The results of this study suggest that probands are likely to quickly communicate their BRCA1/2 test results to relatives and that although needs for social support may motivate family communication, emotionally distant relationships may be a barrier to communication with relatives. © 2001 Wiley-Liss, Inc. [source] State Wildlife Policy and Management: The Scope and Bias of Political ConflictPUBLIC ADMINISTRATION REVIEW, Issue 2 2004Martin Nie State wildlife policy and management are often characterized by divisive political conflict among competing stakeholders. This conflict is increasingly being resolved through the ballot-initiative process. One important reason the process is being used so often is the way state wildlife policy and management decisions are often made by state wildlife commissions, boards, or councils (the dominant way these decisions are made in the United States). These bodies are often perceived by important stakeholders as biased, exclusive, or unrepresentative of nonconsumptive stakeholder values. As a result, unsatisfied interest groups often try to take decision-making authority away from these institutions and give it to the public through the ballot initiative. Cases and examples from Alaska, Arizona, Colorado, and Idaho are examined in this context. The article finishes by outlining four broad alternatives that may be debated in the future: the no change alternative, the authoritative expert alternative, the structural change alternative, and the stakeholder-based collaborative conservation alternative(s). [source] False resurrections: Distinguishing regenerated from spared axons in the injured central nervous systemTHE JOURNAL OF COMPARATIVE NEUROLOGY, Issue 1 2003Oswald Steward Abstract Several recent studies report that axon regeneration can be induced in the mature mammalian nervous system by novel treatments or genetic manipulations. In assessing these reports, it is important to be mindful of the history of regeneration research, which is littered with the corpses of studies that reported regeneration that later proved incorrect. One important reason is the "spared axon conundrum," in which axons that survive a lesion are mistakenly identified as having regenerated. Here, we illustrate the problem and propose criteria that may be used to identify regenerated vs. spared axons, focusing on the injured spinal cord. J. Comp. Neurol. 459:1,8, 2003. © 2003 Wiley-Liss, Inc. [source] Lessons from studies on focal segmental glomerulosclerosis: an important role for parietal epithelial cells?THE JOURNAL OF PATHOLOGY, Issue 3 2006B Smeets Abstract Glomerular diseases are caused by multiple mechanisms. Progressive glomerular injury is characterized by the development of segmental or global glomerulosclerosis independent of the nature of the underlying renal disease. Most studies on glomerular disease focus on the constituents of the filtration barrier (podocytes, glomerular basement membrane (GBM), endothelial cells) or the mesangial cells. Little attention is given to the epithelial cells lining Bowman's capsule, the so called parietal epithelial cells (PECs). This ,lack of attention' is partly explained by the presumed ,passive' function of PECs, which are large, flattened cells that cover Bowman's capsule in a single cell layer and form a barrier between the ultrafiltrate and the periglomerular interstitium, in normal glomerular physiology. A more important reason has been the lack of an established primary role for the parietal epithelium in glomerular diseases. However, in recent years, several studies have demonstrated that PECs are involved in extracapillary proliferation. In addition, PECs can become highly active, proliferating cells, expressing many growth factors, chemokines, cytokines, and their receptors. It was recently demonstrated that PECs also play a part in the development of focal segmental glomerulosclerosis (FSGS). This review summarises current knowledge of the PEC, with emphasis on the role of PECs in the development of FSGS. Copyright © 2006 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. [source] Dimensional Stability of the Free Fascia Grafts: An Animal Experiment,THE LARYNGOSCOPE, Issue 4 2002Shabbir Indorewala MS (ENT) Abstract Objectives/Hypothesis It appears that autologous free fascia grafts (fascia lata and temporal fascia) change their dimensions during the vital first 5 days of healing. Poor dimensional stability of these grafts can be an important reason for failure of complete closure of tympanic membrane perforations in tympanoplasty operations. There has been no study regarding this dimensional instability. Study Design Prospectively dimensional instability of the free fascia grafts was studied in 14 mongrel dogs. Methods Fourteen healthy Mongrel dogs were operated on twice. During the first surgery, fascia lata and temporal fascia grafts of measured dimensions (length, breadth, and thickness) were implanted in the subcutaneous pockets on the thoracoabdominal wall of the same dog (autograft). Five dogs were operated on again after 2 days, and 7 dogs were operated on again after 5 days to harvest the implanted grafts. The dimensions of the harvested grafts were noted. Changes with respect to their implant dimensions after 2 days and after 5 days were calculated. Results It was found that free fascia lata exhibits significantly superior dimensional stability when compared with free temporal fascia during the early healing phase, before graft integration has occurred. Shrinking and thickening of temporal fascia are greaterand are also most unpredictable. Conclusions Poor dimensional stability of temporal fascia may compromise a well-sealed perforation at the time of surgery, and it may reopen by the 5th day. This must be one of the causes of failure of tympanoplasty, which needs to be studied further. [source] The problem of meeting dietary protein requirements in intensive aquaculture of marine fish larvae, with emphasis on Atlantic halibut (Hippoglossus hippoglossus L.)AQUACULTURE NUTRITION, Issue 3 2007A. KVÅLE Abstract Atlantic halibut (Hippoglossus hippoglossus) achieve a mature gastrointestinal tract approximately 2 months after first feeding (12 °C). The immature digestion may be the reason that compound diets fail to sustain growth and survival in first feeding halibut larvae and in larvae of other marine fish species. On the other hand, larvae fed with live feeds are capable of extraction of sufficient quantities of nutrients to sustain high growth rates. A lower availability of the protein in formulated diets compared with live prey is considered to be an important reason for the low performance of formulated diets. One approach to increase dietary protein availability is supplementation of pre-digested proteins. Experiments using tube fed individual larvae show that halibut larvae are able to utilize hydrolysed protein more efficiently than intact protein. However, Atlantic halibut in culture did not respond well to dietary supplementation of hydrolysed protein, in contrast to some other species. One reason may be extensive leaching of pre-hydrolysed proteins from the microparticulate feed. Atlantic halibut are slow feeders and may thus suffer more from nutrient leaching than species eating more rapidly. Feed formulation techniques affect dietary protein leaching, and in this paper, different techniques and their impact on feed properties are described. Microbound diets are most widely used in larval rearing, but show high rates of nutrient leaching. Lipid-based capsules seem to have the best potential to prevent leaching, however, they are not able to deliver a complete diet. The high need for improvements in larval feed formulation techniques are clearly stated, and some suggestions are given. Among these are production of complex particles, where small lipid-based capsules or liposomes containing the low molecular weight water-soluble nutrients are embedded. In such feed particles the water-soluble molecules are protected from leaching. Techniques for delivery of water-soluble nutrients that are needed in large quantities, i.e. free amino acids or hydrolysed and water-soluble protein, remain to be developed. [source] Investigating the relationship between affluence and elective caesarean sectionsBJOG : AN INTERNATIONAL JOURNAL OF OBSTETRICS & GYNAECOLOGY, Issue 7 2005Bernadette Alves The proportion of women delivering by caesarean section has increased dramatically in England and many westernised countries. It has been suggested that one important reason for this increase is the growing proportion of women opting for elective caesareans for lifestyle reasons, a trend that is, it is argued, most common among the affluent. We investigated the hypothesis that affluent women are more likely to deliver by elective caesarean section. Logistic regression modelling was used to analyse data from half a million women who delivered in English NHS hospitals between 1996 and 2000. We found that women living in the most affluent areas of England were significantly more likely to have an elective caesarean section than their deprived counterparts. [source] Uranium Provinces in ChinaACTA GEOLOGICA SINICA (ENGLISH EDITION), Issue 3 2000CHEN Zhaobo Abstract, Three uranium provinces are recognized in China, the Southeast China uranium province, the Northeast China-Inner Mongolia uranium province and the Northwest China (Xinjiang) uranium province. The latter two promise good potential for uranium resources and are major exploration target areas in recent years. There are two major types of uranium deposits: the Phanerozoic hydrothermal type (vein type) and the Meso-Cenozoic sandstone type in different proportions in the three uranium provinces. The most important reason or prerequisite for the formation of these uranium provinces is that Precambrian uranium-enriched old basement or its broken parts (median massifs) exists or once existed in these regions, and underwent strong tectonomagmatic activation during Phanerozoic time. Uranium was mobilized from the old basement and migrated upwards to the upper structural level together with the acidic magma originating from anatexis and the primary fluids, which were then mixed with meteoric water and resulted in the formation of Phanerozoic hydrothermal uranium deposits under extensional tectonic environments. Erosion of uraniferous rocks and pre-existing uranium deposits during the Meso-Cenozoic brought about the removal of uranium into young sedimentary basins. When those basins were uplifted and slightly deformed by later tectonic activity, roll-type uranium deposits were formed as a result of redox in permeable sandstone strata. [source] Low rates of colorectal, cervical, and breast cancer screening in Asian Americans compared with non-Hispanic whitesCANCER, Issue 1 2006Cultural influences or access to care? Abstract BACKGROUND Asian Americans have lower cancer screening rates compared with non-Hispanic whites (NHWs). Little is known about mechanisms that underlie disparities in cancer screening. The objectives of the current study were 1) to determine the relation between nativity, years in the United States, language, and cancer screening in NHWs and Asian Americans, independent of access to care and 2) to determine whether Asians reported different reasons than NHWs for not obtaining cancer screening. METHODS This population-based study included 36,660 NHWs, 1298 Chinese, 944 Filipinos, 803 Koreans, 857 Vietnamese, and 1036 Other Asians from the 2001 California Health Interview Survey. The main study outcomes were 1) self-reported colorectal, cervical, and breast cancer screening and 2) reasons for not obtaining cancer screening. RESULTS After adjusting for access to care, several Asian subgroups still had significantly lower rates of all types of cancer screening compared with NHWs. Adjusting for nativity, years in the United States, and English language attenuated the relation between Asian ethnicity and lower rates of colorectal and breast cancer screening. When they were asked what the most important reason was for not having each screening test, foreign-born Asians were significantly more likely than United States-born NHWs to report that they "didn't have problems/symptoms" (P<.01). CONCLUSIONS Nativity, years in the United States, and English language may be markers of cultural differences that are mediating cancer screening disparities. Foreign-born Asians may believe that cancer screening is in response to symptoms rather than tests that are used prior to the development of symptoms. Health education messages must consider how to communicate effectively that "cancer screening is valuable, because it finds cancer before it is advanced enough to cause symptoms." Cancer 2006. © 2006 American Cancer Society. [source] Heavy silicone oil versus standard silicone oil as vitreous tamponade in inferior PVR (HSO Study): design issues and implicationsACTA OPHTHALMOLOGICA, Issue 6 2007Antonia M. Joussen Abstract. Purpose:, Proliferative vitreoretinopathy (PVR) is the most important reason for blindness following retinal detachment. Presently, vitreous tamponades such as gas or silicone oil cannot contact the lower part of the retina. A heavier-than-water tamponade displaces the inflammatory and PVR-stimulating environment from the inferior area of the retina. The Heavy Silicone Oil versus Standard Silicone Oil Study (HSO Study) is designed to answer the question of whether a heavier-than-water tamponade improves the prognosis of eyes with PVR of the lower retina. Methods:, The HSO Study is a multicentre, randomized, prospective controlled clinical trial comparing two endotamponades within a two-arm parallel group design. Patients with inferiorly and posteriorly located PVR are randomized to either heavy silicone oil or standard silicone oil as a tamponading agent. Three hundred and fifty consecutive patients are recruited per group. After intraoperative re-attachment, patients are randomized to either standard silicone oil (1000 cSt or 5000 cSt) or Densiron® as a tamponading agent. The main endpoint criteria are complete retinal attachment at 12 months and change of visual acuity (VA) 12 months postoperatively compared with the preoperative VA. Secondary endpoints include complete retinal attachment before endotamponade removal, quality of life analysis and the number of retina affecting re-operation within 1 year of follow-up. Results:, The design and early recruitment phase of the study are described. Conclusions:, The results of this study will uncover whether or not heavy silicone oil improves the prognosis of eyes with PVR. [source] Is MRSA more virulent than MSSA?CLINICAL MICROBIOLOGY AND INFECTION, Issue 9 2007F. Rozgonyi Abstract Numerous clinical studies have indicated, based on mortality rates, that methicillin-resistant Staphylococcus aureus (MRSA) strains are more virulent than methicillin-susceptible S. aureus (MSSA) strains. In contrast, quantitative laboratory examinations of the presence and magnitude of pathogenic mechanisms and virulence factors in strains of MRSA and MSSA have generated conflicting data. The most important reason for these conflicting results is probably the heterogeneic nature of the resistant population. A comparison of selected and congenic MRSA and MSSA sub-populations of the same strain is required to resolve this issue. [source] | ||||||||||||||||||||||||||||||||||||||||