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Selected AbstractsSeasonal Prevalence of Mosquitoes Collected from Light Traps in Korea (1999-2000)ENTOMOLOGICAL RESEARCH, Issue 1 2003Heung Chul KIM ABSTRACT Adult mosquito collections were conducted from 1999 through 2000 at 29 US military installations located in six provinces in the Republic of Korea (ROK). Adult mosquitoes were collected in New Jersey light traps from 15 May to 15 October each year. Adult mosquito surveillance was conducted to determine the appropriate time for pesticide applications at each of the Army installations. A total of 68,051 and 62,526 adults were collected in 1999 and 2000 respectively, comprising 53,983 (79.3%) females and 14,068 (20.7%) males in 1999, and 50,274 (80.4%) females and 12,252 (19.6%) males in 2000. A total of 19 species from 7 genera were collected. The most common species collected were Anopheles sinensis (34.2%), Culex tritaeniorhynchus (29.4%), Aedes vexans nipponii (18.2%) and Culex pipiens (16.8%). Anopheles sinensis were collected at the same level while Culex tritaeniorhynchus decreased by 6.2% in 2000. The weekly population densities for some species were variable for each of the years, apparently as a result of changing weather conditions. [source] Interpreting the Process of Change in Higher Education: The Case of the Research Assessment ExercisesHIGHER EDUCATION QUARTERLY, Issue 1 2003Ted Tapper Given that the current Research Assessment Exercise (RAE 2001) has been completed, it is an appropriate time to explore the impact of the RAEs upon the character of British higher education. This timeliness is reinforced by the earlier publication of HEFCE's own ,Review of Research' (September 2000), the report from the House of Commons' Select Committee on Science and Technology Committee (April 2000), with a report due in April 2003 from the Joint Funding Bodies (under the auspices of Gareth Roberts). We are therefore in a period of review and consultation, which may culminate in a new assessment regime or, as its severest critics would hope, even its demise. While our analysis genuflects to these contemporary developments, it is constructed within a framework that interprets the RAE process as constituting a continuous struggle for the control of the production of high-status knowledge. [source] Long-term patient monitoring for clozapine-induced agranulocytosis and neutropenia in Korea: when is it safe to discontinue CPMS?HUMAN PSYCHOPHARMACOLOGY: CLINICAL AND EXPERIMENTAL, Issue 6 2006Byung-Jo Kang Abstract Objectives This study documents the incidences of agranulocytosis and neutropenia, and the patterns of incidence of the side effects of long-term clozapine treatment in order to determine an appropriate time to stop the Clozaril Patient Monitoring System (CPMS). Methods Hematological, demographic, and other data from the CPMS for 6782 patients who took clozapine for the past 11 years in the Republic of Korea has been analyzed. Results Twenty-nine (53.7%) of fifty-four agranulocytosis cases occurred within the first 18 weeks. The cumulative incidence of agranulocytosis was 1.64% between 6 and 11 years and the crude incidence was 0.8%. Neutropenia occurred in 697 patients, and 365 (52.4%) of these cases occurred within the first 18 weeks. The cumulative incidence of neutropenia was 19.8% between 8 and 11 years, and the crude incidence was 10.3%. There were no cases of agranulocytosis or neutropenia after the 9th year of clozapine treatment. Conclusions The incidence of agranulocytosis in the Republic of Korea was similar to those in the rest of the world. While agranulocytosis began several years after clozapine treatment, long-term monitoring of white blood cells is necessary. We suggest that the CPMS should be stopped or less frequently after the 9th year of treatment. Copyright © 2006 John Wiley & Sons, Ltd. [source] Calcium supplementation of breeding birds: directions for future researchIBIS, Issue 4 2004S. James Reynolds Calcium is an essential nutrient for avian reproduction. Calcium-rich foods are consumed by breeding birds for production of eggshells and for provisioning chicks that are mineralizing skeletal tissues. A number of studies have documented calcium-limited reproduction, and calcium supplementation has been employed over the last decade to demonstrate degrees, causes and consequences of calcium limitation. However, supplementation studies have produced equivocal findings resulting from an absence of calcium limitation in the study species, a poorly designed supplementation procedure or both. Prior to effective calcium supplementation, many factors need to be considered. Calcium-limited breeding in birds can only be detected by monitoring breeding attempts for more than one year and by ensuring that the measured breeding parameters are sensitive to calcium availability. Natural calcium availability needs to be estimated, and daily calcium budgets for the appropriate reproductive stages determined for the study species. Most crucially, if calcium limitation of breeding is caused by secondary calcium limitation (e.g. through heavy metal toxicity), calcium supplementation will probably be ineffective. Effective calcium supplementation will then be achieved through careful planning , a study over several years using appropriate supplements (i.e. naturally occurring ones used by breeding birds), applied at the appropriate time of year (i.e. prelaying and/or chick-rearing phases) and using a response variable that is highly sensitive to calcium availability. If properly planned and performed, calcium supplementation is a cost-effective and potent tool for the study of bird breeding biology. [source] How to keep V(D)J recombination under controlIMMUNOLOGICAL REVIEWS, Issue 1 2004Marjorie A. Oettinger Summary:, Breaking apart chromosomes is not a matter to be taken lightly. The possible negative outcomes are obvious: loss of information, unstable chromosomes, chromosomal translocations, tumorigenesis, or cell death. Utilizing DNA rearrangement to generate the desired diversity in the antigen receptor loci is a risky business, and it must be carefully controlled. In general, the regulation is so precise that the negative consequences are minimal or not apparent. They are visible only when the process of V(D)J recombination goes awry, as for example in some chromosomal translocations associated with lymphoid tumors. Regulation is imposed not only to prevent the generation of random breaks in the DNA, but also to direct rearrangement to the appropriate locus or subregion of a locus in the appropriate cell at the appropriate time. Antigen receptor rearrangement is regulated essentially at four different levels: expression of the RAG1/2 recombinase, intrinsic biochemical properties of the recombinase and the cleavage reaction, the post-cleavage /DNA repair stage of the process, and accessibility of the substrate to the recombinase. Within each of these broad categories, multiple mechanisms are used to achieve the desired aims. The major focus of this review is on accessibility control and the role of chromatin and nuclear architecture in achieving this regulation, although other issues are touched upon. [source] Aetiology, diagnosis and treatment of posterior cross-bites in the primary dentitionINTERNATIONAL JOURNAL OF PAEDIATRIC DENTISTRY, Issue 3 2004M. Malandris Summary., Introduction., Children who present with a posterior cross-bite in the primary dentition may be predisposed to long-term detrimental consequences if the condition is left untreated. Controversy exists in the literature as to the most appropriate time to treat this condition. Objectives., The aim of this review is to evaluate the need for correcting posterior cross-bites in the primary dentition based on the current understanding of the aetiology, likelihood of self-correction, and consequences of various forms of this malocclusion persisting into the mixed and permanent dentitions. A review of the reported treatment options for management of this condition is also presented. Methods., Literature pertaining to the epidemiology and management of posterior cross-bites in the primary dentition are reviewed. Conclusion., Posterior cross-bites in the primary dentition are relatively common and their causes are numerous. Because a significant proportion of posterior cross-bites self-correct beyond the primary dentition, routine correction in the primary dentition phase cannot be advocated. A unilateral posterior cross-bite as a result of a functional displacement of the mandible is one of the few malocclusions which should be considered for correction in the primary dentition. Further research is needed in the management of this condition. [source] Personality and Performance at the Beginning of the New Millennium: What Do We Know and Where Do We Go Next?INTERNATIONAL JOURNAL OF SELECTION AND ASSESSMENT, Issue 1-2 2001Murray R. Barrick As we begin the new millennium, it is an appropriate time to examine what we have learned about personality-performance relationships over the past century and to embark on new directions for research. In this study we quantitatively summarize the results of 15 prior meta-analytic studies that have investigated the relationship between the Five Factor Model (FFM) personality traits and job performance. Results support the previous findings that conscientiousness is a valid predictor across performance measures in all occupations studied. Emotional stability was also found to be a generalizable predictor when overall work performance was the criterion, but its relationship to specific performance criteria and occupations was less consistent than was conscientiousness. Though the other three Big Five traits (extraversion, openness and agreeableness) did not predict overall work performance, they did predict success in specific occupations or relate to specific criteria. The studies upon which these results are based comprise most of the research that has been conducted on this topic in the past century. Consequently, we call for a moratorium on meta-analytic studies of the type reviewed in our study and recommend that researchers embark on a new research agenda designed to further our understanding of personality-performance linkages. [source] Hematopoietic progenitor cells (HPC) and immature reticulocytes evaluations in mobilization process: new parameters measured by conventional blood cell counterJOURNAL OF CLINICAL LABORATORY ANALYSIS, Issue 4 2006J.F.A. Noronha Abstract Monitoring the timing of leukapheresis in peripheral blood stem cells (PBSC) mobilization is an important clinical decision that requires an accurate analytical tool. The present study assessed hematopoietic progenitor cells (HPC) and immature reticulocyte fraction (IRF) counts provided by a routine automated blood counter as potential parameters for predicting the appropriate time for harvesting. The HPC and IRF values were compared with white blood cell (WBC) and CD34+ cell counts obtained by flow cytometry in 30 adult patients with hematological malignancies undergoing PBSC mobilization. It was observed that there was a significant correlation between HPC counts and CD34+ cells in peripheral blood counts (r=0.61, P=0.0003) and between the number of HPC and CD34+cells collected by leukapheresis (r=0.5733, P=0.0009). Comparing HPC, IRF, WBC, and CD34+ cells parameters as a sign of hematological recovery showed that the raise in immature reticulocytes counts preceded the increase of WBC (P=0.0002), HPC (P=0.0001), and CD34+ (P=0.0001) cells in peripheral blood counts. According to our results, HPC and IRF parameters may be integrated into clinical protocols to evaluate the timing of leukapheresis. IRF, as previously demonstrated in bone marrow transplantation, is the earliest sign of hematopoietic recovery in mobilization process. J. Clin. Lab. Anal. 20:149,153, 2006. © 2006 Wiley-Liss, Inc. [source] The status of training and education in information and computer technology of Australian nurses: a national surveyJOURNAL OF CLINICAL NURSING, Issue 20 2008Robert Eley Aims and objectives., A study was undertaken of the current knowledge and future training requirements of nurses in information and computer technology to inform policy to meet national goals for health. Background., The role of the modern clinical nurse is intertwined with information and computer technology and adoption of such technology forms an important component of national strategies in health. The majority of nurses are expected to use information and computer technology during their work; however, the full extent of their knowledge and experience is unclear. Design., Self-administered postal survey. Methods., A 78-item questionnaire was distributed to 10,000 Australian Nursing Federation members to identify the nurses' use of information and computer technology. Eighteen items related to nurses' training and education in information and computer technology. Results., Response rate was 44%. Computers were used by 86·3% of respondents as part of their work-related activities. Between 4,17% of nurses had received training in each of 11 generic computer skills and software applications during their preregistration/pre-enrolment and between 12,30% as continuing professional education. Nurses who had received training believed that it was adequate to meet the needs of their job and was given at an appropriate time. Almost half of the respondents indicated that they required more training to better meet the information and computer technology requirements of their jobs and a quarter believed that their level of computer literacy was restricting their career development. Nurses considered that the vast majority of employers did not encourage information and computer technology training and, for those for whom training was available, workload was the major barrier to uptake. Nurses favoured introduction of a national competency standard in information and computer technology. Conclusions., For the considerable benefits of information and computer technology to be incorporated fully into the health system, employers must pay more attention to the training and education of nurses who are the largest users of that technology. Relevance to clinical practice., Knowledge of the training and education needs of clinical nurses with respect to information and computer technology will provide a platform for the development of appropriate policies by government and by employers. [source] Inflammatory bowel disease in the Asia,Pacific area: A comparison with developed countries and regional differencesJOURNAL OF DIGESTIVE DISEASES, Issue 3 2010Vineet AHUJA The Asia,Pacific region has been marked as an area with a low incidence of inflammatory bowel disease (IBD), although confusion always existed as to whether this low incidence was a result of low diagnostic awareness, a high incidence of infective diarrhoea and its diagnostic overlap or a true low incidence. As epidemiological studies from this region are being made available it is clear that the incidence and prevalence rates of IBD in Asia,Pacific region are low compared with Europe and North America. They are however, increasing rapidly. There are substantial variations in the incidence and prevalence rates of IBD in various ethnic groups in Asia. The highest incidence rates are recorded from India, Japan and the Middle East and there exists a genetic predisposition of South Asians (Indians, Pakistanis and Bangladeshis) to ulcerative colitis (UC). It appears that certain racial groups are more prone than others to develop IBD. For instance, Indians in South-East Asia have higher rates than Chinese and Malays. While there is a host genetic predisposition, environmental factor(s) may be responsible for this difference. The clinical phenotypes and complication rates of Asian IBD resemble those of the Caucasian population in general, but some heterogeneity is observed in different regions of Asia. There is no evidence of a north-south or an east-west divide in the Asia,Pacific region. The available studies suggest an increasing incidence of UC in the Asia,Pacific region and hence it is an appropriate time to launch well-designed epidemiological studies so that etiopathogenetic factors can be identified. There is a male predominance in Crohn's disease in the Asian population. The NOD2/CARD15 gene is not associated with CD in the Japanese, Korean, Chinese and Indian population. [source] Current Concerns in Validity TheoryJOURNAL OF EDUCATIONAL MEASUREMENT, Issue 4 2001Michael T. Kane We are at the end of the first century of work on models of educational and psychological measurement and into a new millennium. This certainly seems like an appropriate time for looking backward and looking forward in assessment. Furthermore, a new edition of the Standards for Educational and Psychological Testing (AERA, APA, & NCME, 1999) has been published, and the previous editions of the Standards have served as benchmarks in the development of measurement theory. This backward glance will be just that, a glance. After a brief historical review focusing mainly on construct validity, the current state of validity theory will be summarized, with an emphasis on the role of arguments in validation. Then how an argument-based approach might be applied will be examined in regards to two issues in validity theory: the distinction between performance-based and theory-based interpretations, and the role of consequences in validation. [source] Population trends and habitat use of Harlequin Ducks in Rhode IslandJOURNAL OF FIELD ORNITHOLOGY, Issue 3 2007Christine M. Caron ABSTRACT To assess population trends of Harlequin Ducks (Histrionicus histrionicus) in Rhode Island (U.S.A.), we analyzed Christmas Bird Counts and other historical surveys and also conducted surveys during the winter of 2005,2006. We estimated sex and age ratios, evaluated the effects of tidal regime and time of day on survey precision, and quantified habitat use. The population in Rhode Island experienced logistic growth from 1976 to 2004, with approximately 150 birds now wintering at three primary sites in the state. We estimated that the current ratio of males to females in the region was 1.6:1 (62% males) and that 13% of males were first-winter birds. Most Harlequin Ducks were observed in rocky habitats within 50 m of the shore or offshore islands. We detected the greatest numbers of birds, with the least amount of variation, during morning surveys at low tide, suggesting that this may be the most appropriate time for population monitoring. Increases in the Rhode Island population and male-biased sex ratios may indicate a local population recovery resulting from a hunting ban initiated in 1990. Although most Harlequin Ducks in eastern North America winter in Maine, the population in Rhode Island represents one of the largest in the southern part of their range. SINOPSIS Para determinar las tendencias poblacionales de arlequines (Histrionicus histrionicus), en Rhode Island, analizamos los conteos navideños, otros censos históricos y además llevamos a cabos censos durante el invierno de 2005,2006. Cuantificamos el uso de habitat, estimamos la tasa de edad y sexos y evaluamos el efecto del régimen de mareas y la hora del dia en la presición de los censos. La población de patos arlequines experimentó un crecimiento logístico de 1976,2004, con unos 150 patos pasando el invierno en tres localidades primarias, del estado. Estimamos una tasa de 1.6:1 de machos a hembras (62% de machos), siendo un 13% de los machos individuos de primer invierno. La mayoría de las aves fueron observadas en hábitats rocosos a unos 50 m de la playa o en islas cerca de la playa. Detectamos el mayor número de aves, con la menor variación, en los censos que se llevaron a cabo durante la marea baja, lo que sugiere que este es el momento más apropiado para monitorear sus poblaciones. El aumento de estas aves en Rhode Island, el sesgo en su sexo, hacia mayor cantidad de machos, pudiera indicar, de un recobro poblacional como resultado la prohibición de su cacería a partir de 1990. Aunque la mayoría de los arlequines de la parte este de los EUA pasan el invierno en Maine, la población de Rhode Island representa una de las mayores en la parte sur de su distribución. [source] Temperature and Photoperiod Interact to Affect Reproduction and GnRH Synthesis in Male Prairie VolesJOURNAL OF NEUROENDOCRINOLOGY, Issue 6 2000L. J. Kriegsfeld Prairie voles (Microtus ochrogaster), like most rodent species, exhibit a phenotypic polymorphism in reproductive response to winter conditions or to short day lengths in the laboratory. Laboratory studies on seasonally breeding species have traditionally focused on the role of photoperiod in modulating reproduction and other seasonal adaptions. However, because animals use proximate environmental factors in addition to photoperiod to phase seasonal adaptions with the appropriate time of year, the present study investigated the interaction of photoperiod and temperature on reproductive function and the gonadotropin-releasing hormone (GnRH) neuronal system. Male prairie voles were housed in either long (LD 16:8) or short (LD 8:16) photoperiods. Voles in each photoperiodic condition were also exposed to either mild (20 °C) or low (8 °C) temperatures. After 10 weeks, voles were killed and their brains were processed using in situ hybridization for mRNA for proGnRH. The results suggest that GnRH synthesis is not affected by exposure to a single inhibitory proximate factor (i.e. short days or low temperatures alone), even when reproduction is inhibited, whereas a combination of inhibitory proximate factors leads to a decrease in GnRH synthesis (i.e. fewer neurones staining for mRNA for proGnRH). These data suggest that the neuroendocrine mechanisms regulating seasonal alterations in reproductive function are likely to differ between harsh and mild winters. [source] Maternal Mortality in Rural India: A Hospital Based, 10 Year Retrospective AnalysisJOURNAL OF OBSTETRICS AND GYNAECOLOGY RESEARCH (ELECTRONIC), Issue 4 2001Dr. Kavita Verma Abstract Objectives: To estimate the maternal mortality ratio (MMR) in Ludhiana, a city of Northern India in order to determine the causes associated with MMR and to suggest ways to reduce it. Methods: Retrospective analysis of the mortality records of obstetrics cases in Christian Medical College, Ludhiana, India. Results: The mean MMR for the 10 year period was 785 per 100,000 live births. Of the total 116 reported maternal deaths, 44 (41.9%) were due to induced septic abortion. The reasons were unwanted pregnancy in 22 (50%) and 11 (25%) were female feticide. Conclusions: In our hospital based analysis, MMR was very high. Most maternal deaths are preventable by intervention at the appropriate time and it is important for health professionals, policy makers and politicians to implement the introduction of programs for reducing maternal mortality. Special emphasis should be placed on antenatal care, the establishment of a registration system and measures to abolish illegal abortion. [source] Medication Adherence Among Adolescents in a School-Based Health CenterJOURNAL OF SCHOOL HEALTH, Issue 2 2006Cynthia J. Mears Medication adherence for these patients may be challenging because the student is often responsible for bringing home the prescription and receiving the instructions. This study assesses medication fill, initiation, and adherence rates among adolescents in a school-based health center to identify major barriers to medication compliance. Students enrolled in a school-based health center, ,10 years old, able to read and write English, and whose parent had provided consent for participation, were eligible for the study. Eligible students who received a prescription from the health center were invited to return to the clinic a week later to complete a questionnaire (with verbal assent). Primary outcome measures included medication fill rates, medication initiation rates, medication adherence rates, and reasons for nonadherence. Eighty-one students completed the questionnaire: 45 students (55.6%) filled their prescription. Of the students who filled their prescriptions, 75.6% reported always taking their medication at the appropriate time, 22.2% reported sometimes forgetting to take their medication, and 2.2% reported never taking the medication. However, many discrepancies were found between reported medication-taking behavior and the instructions provided to the student. Medication fill, initiation, and adherence rates among students receiving prescriptions for medications in school-based health centers are suboptimal. Interventions that address key identified barriers need to be developed and evaluated in order to achieve optimal fill and adherence rates. (J Sch Health. 2006;76(2):52-56) [source] THE IMPACT OF HOMOGENIZATION AND MICROFILTRATION ON RENNET-INDUCED GEL FORMATIONJOURNAL OF TEXTURE STUDIES, Issue 4 2008STEPHAN THOMANN ABSTRACT The effects of the independent variables, milk homogenization pressure (p1), concentration factor of milk microfiltration (i) and pH on the rheological properties of rennet milk gels were studied. Nondestructive oscillatory rheometry was used to determine rennet coagulation time (RCT), curd firming rate (CFR) and cutting time (CT). A central composite design, comprising two levels of i (1 and 2), pH (6.4 and 6.6) and p1 (0 and 8 MPa), was applied. Second-order polynomial models successfully described (R2 > 0.92) the relationship between processing parameters and rheological properties of the gels. pH had the most important influence on RCT, while CFR and CT were strongly influenced by i, pH and the interaction of i and pH. In contradiction to studies on active filler interactions for acid milk gels, a discrepancy was observed between results obtained by compression test and rheometry. Rennet gel firmness strongly decreased with a rise in p1 when measured using the compression test, whereby CFR increased with an increase in p1 when measured using rheometry. The latter result corresponds to higher storage modulus values after a certain time indicating higher gel stiffness. This effect was stronger for concentrated milk than for unconcentrated milk. PRACTICAL APPLICATIONS The use of microfiltration (MF) and homogenization may reduce raw material and processing time in conventional cheese manufacture. However, MF markedly influences milk composition, and homogenization alters the particle size distribution of fat globules. Hence, both technologies may influence rennet-induced gel formation, syneresis, cheese composition and quality. Curd firmness of homogenized milk is often too weak to resist the extensive curd treatment applied in semi-hard cheese manufacture which causes loss of curd fines during the syneresis process and finally decreases cheese yield. MF leads to high curd firmness if cutting is not performed at the appropriate time, which unnecessarily extends processing time. The study of the effect of the individual treatments, as well as of the combination of both on rennet-induced gel formation, is the first important step to evaluate their impact on further processing steps in cheese making. The combination of both technologies may overcome the antagonistic effect of the individual technology as low curd firmness due to homogenization can be compensated by MF that increases curd firmness and vice versa. [source] Dementia and Driving: Autonomy Versus SafetyJOURNAL OF THE AMERICAN ACADEMY OF NURSE PRACTITIONERS, Issue 10 2005Article first published online: 23 SEP 200, Charlene Hoffman Snyder MSN, NP-BC Purpose This article reviews the effects of various types of dementia on driving skills, the available assessment measures, legal considerations, and the important role played by the nurse practitioner (NP) in the process of recommending driving cessation. It provides strategies and resources that may offer guidance to NPs who are attempting to balance the continued independence of patients with dementia, as represented by driving, with the safety not only of such patients but also of the public at large. Data sources A review of the biomedical literature, resources available on the World Wide Web, and illustrative case studies were used. Conclusions The diagnosis of dementia alone is often insufficient to determine driver competence because the topographic losses of dementia are complex. Recognizing when cessation should occur is made more difficult because objective assessment tools do not exist to predict impaired driving skills. Recommending driving cessation at the appropriate time can be a challenge for NPs, who must balance such a significant impact on the driver's autonomy with concerns about public safety if the patient continues to drive despite progressive impairment. Implications for practice The progressive loss of cognitive abilities in dementia presents a series of ongoing challenges for the patient throughout the disease continuum. Unfortunately, the recommendation to stop driving can present one of the more immediate issues confronting the patient, the family, and the healthcare provider. Failure to assess diminished driving skill can lead either to premature or to delayed driving cessation. Either outcome can have adverse effects on the patient, the patient's family, and public safety. [source] Spawning and recruitment patterns of major fish species in Bontanga Reservoir, Ghana, West AfricaLAKES & RESERVOIRS: RESEARCH AND MANAGEMENT, Issue 1 2010Kwadwo Kwarfo-Apegyah Abstract The spawning and recruitment patterns of the major Cichlid fish species, including Hemichromis fasciatus, Oreochromis niloticus, Sarotherodon galilaeus, Tilapia zillii and other species, Auchenoglanis occidentalis, Brycinus nurse, Clarias gariepinus and Marcusenius senegalensis were studied for 24 months in Bontanga Reservoir, Ghana, using length-based fish stock assessment approaches. The species spawned throughout the year, with two spawning pulses described as major and minor spawning seasons. The major spawning season occurred from March to September for the Cichlids, and from May to September for the other species. The minor spawning season, indicative of extended spawning, occurred from October to March for all the fish stocks. Fish spawning began with the onset of the rains in April/May, peaking by June/July, before the rainfall peak in August for all the fish stocks studied. Recruitment was found to occur throughout the year, with major and minor pulses coinciding with the major and minor spawning seasons. Accordingly, the most appropriate time for a possible closed fishing period appears to be from June to August, 1 month after the start of, and before the end of, the rains. The estimated mean standard length (Lm) for first time spawners of A. occidentalis, B. nurse, C. gariepinus and H. faciatus were 11.7, 12.7, 2.7 and 7.5 cm respectively. The estimated maturity,length ratio of 0.4 and 0.2 for O. niloticus, S. galilaeus and T. zillii were lower than the known 0.7 for normal growth, suggesting the tilapias matured faster, and at a smaller size, in the reservoir. Apparent sexual precocity associated with early maturity, year-round spawning and recruitment were some important adaptations found to have sustained the reservoir fisheries, even during high fishing pressures. For conservation and sustainable exploitation of the fisheries, instituting a closed fishing season, mesh size regulations, withdrawal rights and a community-based fishery management system are recommended. [source] An Imperfect Contraceptive Society: Fertility and Contraception in ItalyPOPULATION AND DEVELOPMENT REVIEW, Issue 3 2009Alessandra Gribaldo Italy represents an unexpected and in some ways paradoxical outcome in terms of fertility control: a drop to one of the lowest birth rates in the world has been accompanied by continuing extensive use of traditional methods despite the availability of modern contraception. Using data from 349 interviews conducted in 2005,06 in four Italian cities, we argue that Italian women commonly achieve "unplanned" and desired conceptions through the use of withdrawal and natural methods. While data from other countries reveal similar notions of ambivalence surrounding pregnancy intentions and contraceptive use, Italy stands out for the surprising correlation between highly "managing" the conditions under which children are born and the socially commended approach of "letting births happen." Such results suggest the need to rethink theoretical understandings of low fertility. Through the use of non-technological methods, individuals manipulate culturally produced norms and beliefs about the appropriate time to have a child; simultaneously, their actions are embedded in larger cultural, economic, and political processes. [source] Transition from Batch to Continuous Operation in Bio-Reactors: A Model Predictive Control Approach and ApplicationTHE CANADIAN JOURNAL OF CHEMICAL ENGINEERING, Issue 4 2007Prashant Mhaskar Abstract This work considers the problem of determining the transition of ethanol-producing bio-reactors from batch to continuous operation and subsequent control subject to constraints and performance considerations. To this end, a Lyapunov-based non-linear model predictive controller is utilized that stabilizes the bio-reactor under continuous mode of operation. The key idea in the predictive controller is the formulation of appropriate stability constraints that allow an explicit characterization of the set of initial conditions from where feasibility of the optimization problem and hence closed-loop stability is guaranteed. Additional constraints are incorporated in the predictive control design to expand on the set of initial conditions that can be stabilized by control designs that only require the value of the Lyapunov function to decay. Then, the explicit characterization of the set of stabilizable initial conditions is used in determining the appropriate time for which the reactor must be run in batch mode. Specifically, the predictive control approach is utilized in determining the appropriate batch length that achieves stabilizable values of the state variables at the end of the batch. Application of the proposed method to the ethanol production process using Zymomonas mobilis as the ethanol producing micro-organism demonstrates the effectiveness of the proposed model predictive control strategy in stabilizing the bio-reactor. Ce travail porte sur le problème de la détermination de la transition entre le fonctionnement discontinu et continu pour des bioréacteurs produisant de l'éthanol et sur le contrôle subséquent lorsque ceux-ci sont soumis à des contraintes et des considérations de performance. À cette fin, on utilise un contrôleur prédictif par modèles non linéaires de type Lyapunov qui stabilise le bioréacteur lorsqu'il est en mode de fonctionnement continu. L'idée maîtresse dans le contrôleur prédictif est la formulation de contraintes de stabilité appropriées qui permettent une caractérisation explicite du jeu des conditions initiales à partir de laquelle la faisabilité du problème d'optimisation et donc la stabilité en boucle fermée sont garanties. Des contraintes additionnelles sont introduites dans la conception du contrôle prédictif pour étendre le jeu de conditions initiales qui peuvent être stabilisées par la conception du contrôle qui requiert seulement que la valeur de la fonction de Lyapunov diminue. Ensuite, la caractérisation explicite du jeu des conditions initiales stabilisables est utilisée dans la détermination de la durée de fonctionnement adéquate pour laquelle le réacteur doit fonctionner en mode discontinu. Spécifiquement, on utilise la méthode de contrôle prédictif dans la détermination de la longueur discontinue appropriée qui réalise les valeurs stabilisables des variables d'état à la fin du mode discontinu. L'application de la méthode proposée au procédé de production de l'éthanol utilisant Zymomonas mobilis comme microorganisme produisant de l'éthanol, démontre l'efficacité de la stratégie de contrôle prédictif de modèles proposée pour stabiliser le bioréacteur. [source] Roles of glutamate and GABA receptors in setting the developmental timing of spontaneous synchronized activity in the developing mouse cortexDEVELOPMENTAL NEUROBIOLOGY, Issue 12 2007Annette K. McCabe Abstract Spontaneous, synchronized electrical activity (SSA) plays important roles in nervous system development, but it is not clear what causes it to start and stop at the appropriate times. In previous work, we showed that when SSA in neonatal mouse cortex is blocked by TTX in cultured slices during its normal time of occurrence (E17,P3), it fails to stop at P3 as it does in control cultured slices, but instead persists through at least P10. This indicates that SSA is self-extinguishing. Here we use whole-cell recordings and [Ca2+]i imaging to compare control and TTX-treated slices to isolate the factors that normally extinguish SSA on schedule. In TTX-treated slices, SSA bursts average 4 s in duration, and have two components. The first, lasting about 1 s, is mediated by AMPA receptors; the second, which extends the burst to 4 s and is responsible for most of the action potential generation during the burst, is mediated by NMDA receptors. In later stage (P5,P9) control slices, after SSA has declined to about 4% of its peak frequency, bursts lack this long NMDA component. Blocking this NMDA component in P5,P9 TTX-treated slices reduces SSA frequency, but not to the low values found in control slices, implying that additional factors help extinguish SSA. GABAA inhibitors restore SSA in control slices, indicating that the emergence of GABAA -mediated inhibition is another major factor that helps terminate SSA. © 2007 Wiley Periodicals, Inc. Develop Neurobiol, 2007 [source] Multiple Roles for the Endocannabinoid System During the Earliest Stages of Life: Pre- and Postnatal DevelopmentJOURNAL OF NEUROENDOCRINOLOGY, Issue 2008E. Fride The endocannabinoid system, including its receptors (CB1 and CB2), endogenous ligands (,endocannabinoids'), synthesising and degrading enzymes, as well as transporter molecules, has been detected from the earliest stages of embryonic development and throughout pre- and postnatal development. In addition, the endocannabinoids, notably 2-arachidonyl glycerol, are also present in maternal milk. During three distinct developmental stages (i.e. embryonic implantation, prenatal brain development and postnatal suckling), the endocannabinoid system appears to play an essential role for development and survival. Thus, during early pregnancy, successful embryonic passage through the oviduct and implantation into the uterus both require critical enzymatic control of optimal anandamide levels at the appropriate times and sites. During foetal life, the cannabinoid CB1 receptor plays a major role in brain development, regulating neural progenitor differentiation into neurones and glia and guiding axonal migration and synaptogenesis. Postnatally, CB1 receptor blockade interferes with the initiation of milk suckling in mouse pups, by inducing oral motor weakness, which exposes a critical role for CB1 receptors in the initiation of milk suckling by neonates, possibly by interfering with innervation of the tongue muscles. Manipulating the endocannabinoid system by pre- and/or postnatal administration of cannabinoids or maternal marijuana consumption, has significant, yet subtle effects on the offspring. Thus, alterations in the dopamine, GABA and endocannabioid systems have been reported while enhanced drug seeking behaviour and impaired executive (prefrontal cortical) function have also been observed. The relatively mild nature of the disruptive effects of prenatal cannabinoids may be understood in the framework of the intricate timing requirements and frequently biphasic effects of the (endo)cannabinoids. In conclusion, the endocannabinoid system plays several key roles in pre- and postnatal development. Future studies should further clarify the mechanisms involved and provide a better understanding of the adverse effects of prenatal exposure, in order to design strategies for the treatment of conditions such as infertility, mental retardation and failure-to-thrive. [source] Characterization of the pharmacokinetic disposition of levofloxacin in stallions after intravenous and intramuscular administrationJOURNAL OF VETERINARY PHARMACOLOGY & THERAPEUTICS, Issue 5 2008A. GOUDAH The target of the present study was to investigate the plasma disposition kinetics of levofloxacin in stallions (n = 6) following a single intravenous (i.v.) bolus or intramuscular (i.m.) injection at a dose rate of 4 mg/kg bwt, using a two-phase crossover design with 15 days as an interval period. Plasma samples were collected at appropriate times during a 48-h administration interval, and were analyzed using a microbiological assay method. The plasma levofloxacin disposition was best fitted to a two-compartment open model after i.v. dosing. The half-lives of distribution and elimination were 0.21 ± 0.13 and 2.58 ± 0.51 h, respectively. The volume of distribution at steady-state was 0.81 ± 0.26 L/kg, the total body clearance (Cltot) was 0.21 ± 0.18 L/h/kg, and the areas under the concentration,time curves (AUCs) were 18.79 ± 4.57 ,g.h/mL. Following i.m. administration, the mean t1/2el and AUC values were 2.94 ± 0.78 h and 17.21 ± 4.36 ,g.h/mL. The bioavailability was high (91.76% ± 12.68%), with a peak plasma mean concentration (Cmax) of 2.85 ± 0.89 ,g/mL attained at 1.56 ± 0.71 h (Tmax). The in vitro protein binding percentage was 27.84%. Calculation of efficacy predictors showed that levofloxacin might have a good therapeutic profile against Gram-negative and Gram-positive bacteria, with an MIC , 0.1 ,g/mL. [source] Expression of the transcription factor GADD153 is an indicator of apoptosis for recombinant chinese hamster ovary (CHO) cellsBIOTECHNOLOGY & BIOENGINEERING, Issue 6 2001Tracy C. Murphy Abstract Loss of cell viability, through engagement of apoptotic cell death, represents a limitation to maintenance of high levels of productivity of recombinant animal cells in culture. The ability to monitor the status of recombinant cells, and to define indicators of their "well-being," would present a valuable approach to permit a rational intervention at appropriate times during culture. Growth arrest and DNA damage gene 153 (GADD153) is a member of the CCAAT/enhancer-binding protein (C/EBP) family of transcription factors and has been associated with apoptosis. We have examined the expression of GADD153 in conditions associated with apoptosis of recombinant CHO cells in batch culture. GADD153 expression is very low in CHO cells growing in the exponential phase of batch culture but is activated as cells enter the decline phase. Depletion of nutrients (glucose or glutamine) causes activation of GADD153 expression as does the imposition of endoplasmic reticulum stress. In all cases, there is a good relationship between the extent of apoptosis that occurs in response to each stress and the degree of GADD153 expression. In addition, nutrient refeeding or reversal of stress produces a concomitant decrease in expression of GADD153 and the susceptibility to apoptosis. Thus, GADD153 appears to offer a valid indicator of apoptosis and illustrates the potential for definition of monitors of cellular status related to the likelihood of apoptosis of cell populations. © 2001 John Wiley & Sons, Inc. Biotechnol Bioeng 75: 621,629, 2001. [source] ANABOLIC AGENTS FOR IMPROVING MUSCLE REGENERATION AND FUNCTION AFTER INJURYCLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 7 2008Gordon S Lynch SUMMARY 1In the present review, we describe how muscles can be injured by external factors, internal factors or during the performance of some actions during sports. In addition, we describe the injury to a muscle that occurs when its blood supply is interrupted, an occurrence common in clinical settings. An overview of muscle regeneration is presented, as well as a discussion of some of the potential complications that can compromise successful muscle repair and lead to impaired function and permanent disability. 2Improving muscle regeneration is important for hastening muscle repair and restoring muscle function and the present review describes ways in which this can be achieved. We describe recent advances in tissue engineering that offer considerable promise for treating muscle damage, but highlight the fact that these techniques require rigorous evaluation before they can become mainstream clinical treatments. 3Growth-promoting agents are purported to increase the size of existing and newly regenerating muscle fibres and, therefore, could be used to improve muscle function if administered at appropriate times during the repair process. The present review provides an update on the efficacy of some growth-promoting agents, including anabolic steroids, insulin-like growth factor-I (IGF-I) and b2 -adrenoceptor agonists, to improve muscle function after injury. Although these approaches have clinical merit, a better understanding of the androgenic, IGF-I and b-adrenoceptor signalling pathways in skeletal muscle is important if we are to devise safe and effective therapies to enhance muscle regeneration and function after injury. [source] Management of a pregnant patient with Graves' disease complicated by thionamide-induced neutropenia in the first trimesterCLINICAL ENDOCRINOLOGY, Issue 4 2001S. Davison A 31-year-old woman presented with neutropenia due to thionamide drug therapy for Graves' disease. She also reported 8 weeks of amenorrhoea and had a positive pregnancy test. Her drug therapy was discontinued and her neutropenia resolved uneventfully. The hyperthyroidism recurred a week later. After consideration of all treatment options, it was decided to observe until 14 weeks when an elective thyroidectomy was planned. Mother and fetus were monitored closely and both tolerated moderate hyperthyroidism well. At 14 weeks the patient underwent a total thyroidectomy after rendering her euthyroid with a short course of sodium ipodate. Labour was induced at 41 weeks. Delivery was complicated by fetal distress and precipitated a forceps delivery. A 3250 g male infant was born with poor Apgar score and required 2 h of ventilation. At 1 year, the child had reached all developmental milestones at appropriate times. Both mother and fetus may tolerate moderate thyrotoxicosis well in early pregnancy, an alternative that should be considered when thionamide drug therapy is contraindicated. [source] | ||||||||||||||||||||||