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Lower Probability (lower + probability)
Selected Abstractsvoboz: an almost-parameter-free halo-finding algorithmMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 4 2005Mark C. Neyrinck ABSTRACT We have developed an algorithm, called voboz (VOronoi BOund Zones), to find haloes in an N -body dark matter simulation; it has as little dependence on free parameters as we can manage. By using the Voronoi diagram, we achieve non-parametric, ,natural' measurements of each particle's density and set of neighbours. We then eliminate much of the ambiguity in merging sets of particles together by identifying every possible density peak, and measuring the probability that each does not arise from Poisson noise. The main halo in a cluster tends to have a high probability, while its subhaloes tend to have lower probabilities. The first parameter in voboz controls the subtlety of particle unbinding, and may be eliminated if one is cavalier with processor time; even if one is not, the results saturate to the parameter-free answer when the parameter is sufficiently small. The only parameter that remains, an outer density cut-off, does not influence whether or not haloes are identified, nor does it have any effect on subhaloes; it only affects the masses returned for supercluster haloes. [source] Early adversity in chronic depression: clinical correlates and response to pharmacotherapy,,DEPRESSION AND ANXIETY, Issue 8 2009Daniel N. Klein Ph.D. Abstract Background: There is growing evidence suggesting that early adversity may be a marker for a distinct pathway to major depressive disorder (MDD). We examined associations between childhood adversity and a broad variety of clinical characteristics and response to pharmacotherapy in a large sample of patients with chronic forms of MDD. Methods: Subjects included 808 patients with chronic forms of MDD (chronic MDD, double depression, or recurrent MDD with incomplete recovery between episodes and a total continuous duration of >2 years) who were enrolled in a 12-week open-label trial of algorithm-guided pharmacotherapy. Baseline assessments included a semi-structured diagnostic interview, and clinician- and self-rated measures of depressive symptoms, social functioning, depressotypic cognitions, and personality traits, and childhood adversity. Patients were re-evaluated every 2 weeks. Results: A longer duration of illness; earlier onset; greater number of episodes, symptom severity, self-rated functional impairment, suicidality, and comorbid anxiety disorder; and higher levels of dysfunctional attitudes and self-criticism were each associated with multiple forms of childhood adversity. A history of maternal overcontrol, paternal abuse, paternal indifference, sexual abuse, and an index of clinically significant abuse each predicted a lower probability of remission. Among patients completing the 12-week trial, 32% with a history of clinically significant abuse, compared to 44% without such a history, achieved remission. Conclusions: These findings indicate that a history of childhood adversity is associated with an especially chronic form of MDD that is less responsive to antidepressant pharmacotherapy. Depression and Anxiety, 2009. Published 2009 Wiley-Liss, Inc. [source] Effect of abiotic factors on reproduction in the centre and periphery of breeding ranges: a comparative analysis in sympatric harriersECOGRAPHY, Issue 4 2001J. T. García Variables such as weather or other abiotic factors should have a higher influence on demographic rates in border areas than in central areas, given that climatic adaptation might be important in determining range borders. Similarly, for a given area, the relationship between weather and reproduction should be dissimilar for species which are in the centre of their breeding range and those that are near the edge. We tested this hypothesis on two sympatric ground-nesting raptors, the hen harrier Circus cyaneus and the Montagu's harrier Circus pygargus in Madrid, central Spain, where the hen harrier is at the southern edge of its breeding range in the western Palearctic and the Montagu's harrier is central in its distribution. We examined the reproductive success of both species during an 8-yr period, and looked at the influence of the most stressful abiotic factors in the study area (between-year variation in rainfall and within-year variation in temperature) on reproductive parameters. In the hen harrier, low levels of rainfall during the breeding season had a negative influence on annual fledging success and thus on population fledgling production. The relationship between rainfall and reproduction was probably mediated through food abundance, which in Mediterranean habitat depends directly on rainfall levels. In the Montagu's harrier, no negative effect of dry seasons on productivity was found. Additionally, in the hen harrier, the proportion of eggs that did not hatch in each clutch increased with higher temperatures during the incubation period. No such relationship was found in the Montagu's harrier. We interpret these between-species differences in terms of differences of breeding range and adaptations to the average conditions existing there. Hen harriers, commonest at northern latitudes, are probably best adapted to the most typical conditions at those latitudes, and have probably not developed thermoregulatory or behavioural mechanisms to cope with drought and high temperatures in Mediterranean habitats, in contrast to Montagu's harrier. Thus hen harrier distribution might be constrained by these variables, due to lower reproductive success or higher reproductive costs. Accordingly, a logistic regression analysis of the presence or absence of both species in 289 random points throughout the western Palearctic showed that the distribution of both species was related to temperature, but the relationship was in opposite directions for the two species: hen harriers had lower probability of breeding in areas with higher temperature (as expected in a species with a more northerly distribution). [source] Smoking cessation patterns and predictors of quitting smoking among the Japanese general population: a 1-year follow-up studyADDICTION, Issue 1 2010Akiko Hagimoto ABSTRACT Aim To examine the percentage of Japanese adult smokers who make quit attempts and succeed in smoking cessation over a 1-year period, and to identify predictors of attempts to stop and successful smoking cessation. Design and setting This study used Ipsos JSR Company's access panel, whose sampling framework is based on the Basic Resident Register in Japan. We tracked and monitored a selected sample of smokers who were at least 20 years of age through a baseline postal questionnaire survey in 2005 and a follow-up survey 1 year later. Participants The original response rate was 72.1% (1874 of 2600 smokers). There were 1627 current smokers in the baseline survey, and of those, 1358 were followed-up 1 year later. Findings Among the current smokers, 23.0% reported that they had attempted to quit smoking at least once in the past year. Of those who made quit attempts, 25.6% had achieved 1-week abstinence successfully and 13.5% reported having achieved sustained 6-month abstinence successfully at the time of the follow-up survey. The predictors associated with quit attempts were non-daily smoker, higher motivation to quit and previous attempts to stop smoking. Among smokers who made quit attempts, only 13.5% used nicotine replacement therapy. Higher nicotine dependence was associated with lower probability of success in quitting. Conclusions Japanese smokers attempt to quit at a lower rate than smokers in the United Kingdom and United States, but factors that predict attempts (primarily markers of motivation) and success of attempts (primarily dependence) are similar to those found in western samples. [source] Smokers with financial stress are more likely to want to quit but less likely to try or succeed: findings from the International Tobacco Control (ITC) Four Country SurveyADDICTION, Issue 8 2009Mohammad Siahpush ABSTRACT Objective To examine the association of financial stress with interest in quitting smoking, making a quit attempt and quit success. Design and participants The analysis used data from 4984 smokers who participated in waves 4 and 5 (2005,07) of the International Tobacco Control (ITC) Four Country Survey, a prospective study of a cohort of smokers in the United States, Canada, the United Kingdom and Australia. Measurement The outcomes were interest in quitting at wave 4, making a quit attempt and quit success at wave 5. The main predictor was financial stress at wave 4: ,. . . because of a shortage of money, were you unable to pay any important bills on time, such as electricity, telephone or rent bills?'. Additional socio-demographic and smoking-related covariates were also examined. Findings Smokers with financial stress were more likely than others to have an interest in quitting at baseline [odds ratio (OR): 1.63; 95% confidence interval (CI): 1.22,2.19], but were less likely to have made a quit attempt at follow-up (OR: 0.74; 95% CI: 0.57,0.96). Among those who made a quit attempt, financial stress was associated with a lower probability of abstinence at follow-up (OR: 0.53; 95% CI: 0.33,0.87). Conclusions Cessation treatment efforts should consider assessing routinely the financial stress of their clients and providing additional counseling and resources for smokers who experience financial stress. Social policies that provide a safety net for people who might otherwise face severe financial problems, such as not being able to pay for rent or food, may have a favorable impact on cessation rates. [source] Genetic and demographic responses of mercury-exposed mosquitofish (Gambusia holbrooki) populations: Temporal stability and reproductive components of fitnessENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 10 2002Christopher Paul Tatara Abstract Two previous mesocosm studies showed changes in glucosephosphate isomerase-2 (Gpi-2) allele frequencies in mosquitofish populations exposed to mercury for 111 d or two years. A previous selection component analysis of single-generation populations exposed for 111 d to 18 ,/L Hg suggested that female sexual selection and fecundity selection could contribute to changes in Gpi-2 allele frequencies. The present multigeneration study was conducted to determine the stability of Gpi-2 allele frequencies over four years of mercury exposure, measure the reproductive fitness of Gpi-2 genotypes inhabiting control and mercury-contaminated mesocosms to determine a mechanism explaining changes in Gpi-2 allele frequencies, investigate differences in the demographic characteristics of mercury-exposed and control populations, and investigate the water quality of the mesocosms to determine if variables other than mercury show concordant patterns among mesocosms. Differences in Gpi-2 allele frequencies between control and mercury-exposed populations were stable over four years (, eight generations) of mercury exposure. Mercury-exposed female mosquitofish had a lower probability of being gravid than control females (p = 0.001). Mercury-exposed females also had lower fecundity (total number of eggs and embryos) than control females (p = 0.036). Unlike the results of the more intense mercury exposures in the single generation study, no strong evidence was found that Gpi-2 genotype influenced fecundity or the probability of being gravid in both control and mercury-exposed females. The quantification of fitness components is difficult but has the potential to enhance our understanding of how toxicants alter allele frequencies in exposed populations. [source] In 12-step groups, helping helps the helperADDICTION, Issue 8 2004Sarah E. Zemore ABSTRACT Aims The helper therapy principle suggests that, within mutual-help groups, those who help others help themselves. The current study examines whether clients in treatment for alcohol and drug problems benefit from helping others, and how helping relates to 12-step involvement. Design Longitudinal treatment outcome. Participants An ethnically diverse community sample of 279 alcohol- and/or drug-dependent individuals (162 males, 117 females) was recruited through advertisement and treatment referral from Northern California Bay Area communities. Participants were treated at one of four day-treatment programs. Measurements A helping checklist measured the amount of time participants spent, during treatment, helping others by sharing experiences, explaining how to get help and giving advice on housing and employment. Measures of 12-step involvement and substance use outcomes were administered at baseline and a 6 month follow-up. Findings Helping and 12-step involvement emerged as important and related predictors of treatment outcomes. In the general sample, total abstinence at follow-up was strongly and positively predicted by 12-step involvement at follow-up, but not by helping during treatment; still, helping positively predicted subsequent 12-step involvement. Among individuals still drinking at follow-up, helping during treatment predicted a lower probability of binge drinking, whereas effects for 12-step involvement proved inconsistent. Conclusions Findings support the helper therapy principle and clarify the process of 12-step affiliation. [source] HOST LIFE SPAN AND THE EVOLUTION OF RESISTANCE CHARACTERISTICSEVOLUTION, Issue 1 2007Martin R. Miller There is a wide variety of resistance mechanisms that hosts may evolve in response to their parasites. These can be functionally classified as avoidance (lower probability of becoming infected), recovery (faster rate of clearance), tolerance (reduced death rate when infected), or acquired immunity. It is commonly thought that longer lived organisms should invest more in costly resistance. We show that due to epidemiological feedbacks the situation is often more complex. Using evolutionary theory we examine how the optimal investment in costly resistance varies with life span in a broad range of scenarios. In the absence of acquired immunity, longer lived populations do generally invest more in resistance. If hosts have acquired immunity, the optimal resistance may either increase or decrease with increasing life span. In addition, there may be evolutionary bistability with high and low investments in avoidance or tolerance. The optimal investment in the duration of acquired immunity always increases with life span, and due to bistability, shorter lived hosts may commonly not evolve any immunity. In contrast, the optimal investment in the probability of acquiring immunity initially increases and then decreases with life span. Our results have important implications for the evolution of invertebrate and vertebrate immunity, and for the evolution of acquired immunity itself. [source] Employee choice of flexible spending account participation and health planHEALTH ECONOMICS, Issue 7 2008Barton H. Hamilton Abstract Despite the fact that flexible spending accounts (FSAs) are becoming an increasingly popular employer-provided health benefit, there has been very little empirical study of FSA use among employees at the individual level. This study contributes to the literature on FSAs using a unique data set that provides three years of employee-level-matched benefits data. Motivated by the theoretical model of FSA choice presented in Cardon and Showalter (J. Health Econ. 2001; 20(6):935,954), we examine the determinants of FSA participation and contribution levels using cross-sectional and random-effect two-part models. FSA participation and health plan choice are also modeled jointly in each year using conditional logit models. We find that, even after controlling for a number of other demographic characteristics, non-whites are less likely to participate in the FSA program, have lower contributions conditional on participation, and have a lower probability of switching to new lower cost share, higher premium plans when they were introduced. We also find evidence that choosing health plans with more expected out-of-pocket expenses is correlated with participation in the FSA program. Copyright © 2007 John Wiley & Sons, Ltd. [source] Impact of Furazolidone-Based Quadruple Therapy for Eradication of Helicobacter pylori after Previous Treatment FailuresHELICOBACTER, Issue 4 2002G. Treiber Abstract Background. One week of quadruple therapy including metronidazole is recommended for Helicobacter pylori treatment failures after first line therapy regardless of resistance status. This study investigated whether a quadruple regimen containing furazolidone could be effective as a third-line (salvage) therapy. Methods. All patients with previous H. pylori treatment failure after a clarithromycin-metronidazole ± amoxicillin combination plus acid suppression were given lansoprazole 30 mg twice a day (bid), tripotassiumdicitratobismuthate 240 mg bid, tetracycline 1 g bid, metronidazole 400 mg (PPI-B-T-M) three times a day (tid) for 1 week. In the case of treatment failure with this second-line therapy, the same regimen was applied for 1 week except for using furazolidone 200 mg bid (PPI-B-T-F) instead of metronidazole (sequential study design). Results. Eighteen consecutive patients were treated with PPI-B-T-M. Eleven of those 18 remained H. pylori positive (38.9% cured). Pretherapeutic metronidazole resistance was associated with a lower probability of eradication success (10% vs. 75%, p= .04). Ten of these 11 patients agreed to be retreated by PPI-B-T-F. Final cure of H. pylori with PPI-B-T-F was achieved in 9/10 patients (90%) nonresponsive to PPI-B-T-M. Conclusions. In the presence of metronidazole resistance, PPI-B-T-M as a recommended second-line therapy by the Maastricht consensus conference achieved unacceptable low cure rates in our metronidazole pretreated population. In this population, metronidazole based second-line quadruple therapy may be best suited in case of a metronidazole-free first line-regimen (e.g. PPI-clarithromycin-amoxicillin) or a low prevalence of metronidazole resistance. Furazolidone in the PPI-B-T-F combination does not have a cross-resistance potential to metronidazole and is a promising salvage option after a failed PPI-B-T-M regimen. [source] Toward a general theory of conditional beliefsINTERNATIONAL JOURNAL OF INTELLIGENT SYSTEMS, Issue 3 2006Giulianella Coletti We consider a class of general decomposable measures of uncertainty, which encompasses (as its most specific elements, with respect to the properties of the rules of composition) probabilities, and (as its most general elements) belief functions. The aim, using this general context, is to introduce (in a direct way) the concept of conditional belief function as a conditional generalized decomposable measure ,(·|·), defined on a set of conditional events. Our main tool will be the following result, that we prove in the first part of the article and which is a sort of converse of a well-known result (i.e., a belief function is a lower probability): a coherent conditional lower probability P(·|K) extending a coherent probability P(Hi),where the events His are a partition of the certain event , and K is the union of some (possibly all) of them,is a belief function. © 2006 Wiley Periodicals, Inc. Int J Int Syst 21: 229,259, 2006. [source] Apparent inferiority of first-time breeders in the kittiwake: the role of heterogeneity among age classesJOURNAL OF ANIMAL ECOLOGY, Issue 3 2000Emmanuelle Cam Summary 1.,Many studies have provided evidence that first-time breeders have a lower survival, a lower probability of success, or of breeding, in the following year. Hypotheses based on reproductive costs have often been proposed to explain this. However, because of the intrinsic relationship between age and experience, the apparent inferiority of first-time breeders at the population level may result from selection, and experience may not influence performance within each individual. In this paper we address the question of phenotypic correlations between fitness components. This addresses differences in individual quality, a prerequisite for a selection process to occur. We also test the hypothesis of an influence of experience on these components while taking age and reproductive success into account: two factors likely to play a key role in a selection process. 2.,Using data from a long-term study on the kittiwake, we found that first-time breeders have a lower probability of success, a lower survival and a lower probability of breeding in the next year than experienced breeders. However, neither experienced nor inexperienced breeders have a lower survival or a lower probability of breeding in the following year than birds that skipped a breeding opportunity. This suggests heterogeneity in quality among individuals. 3.,Failed birds have a lower survival and a lower probability of breeding in the following year regardless of experience. This can be interpreted in the light of the selection hypothesis. The inferiority of inexperienced breeders may be linked to a higher proportion of lower-quality individuals in younger age classes. When age and breeding success are controlled for, there is no evidence of an influence of experience on survival or future breeding probability. 4.,Using data from individuals whose reproductive life lasted the same number of years, we investigated the influence of experience on reproductive performance within individuals. There is no strong evidence that a process operating within individuals explains the improvement in performance observed at the population level. [source] The growth,mortality relationship in larval cohorts of Sardinops melanostictus, revealed by using two new approaches to analyse longitudinal data from otolithsJOURNAL OF FISH BIOLOGY, Issue 7 2008G. Plaza The growth,mortality relationship was assessed for larval cohorts of the Japanese sardine Sardinops melanostictus using two new approaches: (1) repeat measures in general linear model (RM-GLMs) and (2) the autoregressive-individual method (AIM). Both methods were compared to the traditional approach in which repeat-measure ANOVA was used to compare the changes in increment width (WI) at age and otolith radii (RO) at age between individuals from an original population and survivors. In RM-GLMs, both the WI at age and RO at age (i.e. at 5, 10, 15 and 20 days) were used as the dependent variables, and the standardized residuals of both regressions RO and age and RO and total length (LT), age class, and day of the year as independent variables. A significant increase in WI at age and RO at age from younger to older age classes was seen as indicative of growth-dependent selection. In AIM, the RO -at-age relationship for each fish was fitted for the first 20 days, using autoregression, and then the growth traits (i.e. slopes) between the original cohorts and survivors were compared using ANOVA. In the traditional approach, the WI at age and RO at age for the first 20 days of an original population were compared with those of survivors sampled in later stages. GLMs and traditional approaches supported the growth rate (i.e. the faster an individual grows, the higher its probability of survival) and bigger is better (i.e. larger individuals at any given age will have lower probability of mortality than smaller individuals of the same age) mechanisms. Furthermore, AIM showed that individuals from original cohorts had lower otolith growth rates than those from survivors, giving further support for the growth,mortality hypothesis for the larval stage of this clupeid. [source] Five-year effects of an anti-poverty program on marriage among never-married mothersJOURNAL OF POLICY ANALYSIS AND MANAGEMENT, Issue 1 2006Anna Gassman-Pines Using data from an experimental evaluation of the New Hope project, an anti-poverty program that increased employment and income, this study examined the effects of New Hope on entry into marriage among never-married mothers. Among never-married mothers, New Hope significantly increased rates of marriage. Five years after random assignment, 21 percent of women assigned to the New Hope condition were married, compared to 12 percent of those assigned to the control group. The New Hope impact on marriage was robust to variations in model specification. The program also increased income, wage growth, and goal efficacy among never-married mothers, and decreased depression. In non-experimental analyses, income and earnings were associated with higher probability of marriage and material hardship was associated with lower probability of marriage. © 2006 by the Association for Public Policy Analysis and Management [source] Cell phone roulette and "consumer interactive" qualityJOURNAL OF POLICY ANALYSIS AND MANAGEMENT, Issue 2 2005Peter Navarro Under current policies, cell phone consumers face a lower probability of finding the best carrier for their usage patterns than winning at roulette. Corroborating survey data consistently show significant dissatisfaction among cell phone users, network performance is a major issue, and customer "churn" is high. This problem may be traced to a new form of "consumer interactive" quality characteristic of emergent high technology products such as cell phone and broadband services. This problem is unlikely to be resolved by effective search and sampling, efficient secondary markets, or voluntary carrier disclosure. Traditional one-dimensional disclosure responses to this new variation on an old asymmetric information problem should give way to a more multi-faceted and fine-grained policy approach. © 2005 by the Association for Public Policy Analysis and Management [source] A Tobit Regression Analysis of the Covariation Between Middle School Students' Perceived School Climate and Behavioral ProblemsJOURNAL OF RESEARCH ON ADOLESCENCE, Issue 2 2010Ming-Te Wang This study uses an ecological framework to examine how adolescents' perceptions of school climate in 6th grade covary with the probability and frequency of their engagement in problem behaviors in 7th and 8th grades. Tobit analysis was used to address the issue of having a highly skewed outcome variable with many zeros and yet account for censoring. The 677 participating students from 8 schools were followed from 6th through 8th grade. The proportions of students reporting a positive school climate perception decreased over the middle school years for both genders, while the level of problem behavior engagement increased. The findings suggested that students who perceived higher levels of school discipline and order or more positive student,teacher relationships were associated with lower probability and frequency of subsequent behavioral problems. [source] Predictors of 16-Year Mortality Among Individuals Initiating Help-Seeking for an Alcoholic Use DisorderALCOHOLISM, Issue 10 2006Christine Timko Background and Methods: We examined rates and predictors of mortality in individuals (47% women) who had just initiated help-seeking for their alcohol use disorders (AUDs) at the start of the study (n=628) and were followed for 16 years. Results: For both women and men, the observed-to-expected mortality ratio (1.4) was lower than rates found in samples of treated individuals with AUDs, suggesting that those initiating help-seeking careers have better chances of long-term survival. Of the individuals for whom cause of death was known, 68% died of alcohol-related causes. Men were more likely to die than were women. When gender was controlled, individuals who were older and unmarried and had more alcohol dependence symptoms at baseline were more likely to die over the 16-year period. When these baseline characteristics were controlled, better drinking outcomes at 1 year were associated with a lower likelihood of subsequent death. The combination of a shorter duration of inpatient/residential care and better drinking outcomes at 1 year was related to a lower probability of death, as was the combination of a longer duration of outpatient care or Alcoholics Anonymous attendance and better drinking outcomes at 1 year. Conclusions: Efforts should be made to help providers identify individuals who are not responding positively to inpatient or residential treatment and intervene to motivate participation in continuing outpatient care and community 12-step self-help groups to reduce the likelihood of a chronic and fatal AUD course. [source] Genetic evidence for sex-biased dispersal in resident bottlenose dolphins (Tursiops aduncus)MOLECULAR ECOLOGY, Issue 6 2004Luciana M. Möller Abstract In most mammals males usually disperse before breeding, while females remain in their natal group or area. However, in odontocete cetaceans behavioural and/or genetic evidence from populations of four species indicate that both males and females remain in their natal group or site. For coastal resident bottlenose dolphins field data suggest that both sexes are philopatric to their natal site. Assignment tests and analyses of relatedness based on microsatellite markers were used to investigate this hypothesis in resident bottlenose dolphins, Tursiops aduncus, from two small coastal populations of southeastern Australia. Mean corrected assignment and mean relatedness were higher for resident females than for resident males. Only 8% of resident females had a lower probability than average of being born locally compared to 33% of resident males. Our genetic data contradict the hypothesis of bisexual philopatry to natal site and suggest that these bottlenose dolphins are not unusual amongst mammals, with females being the more philopatric and males the more dispersing sex. [source] Optimal search for a moving target with the option to waitNAVAL RESEARCH LOGISTICS: AN INTERNATIONAL JOURNAL, Issue 6 2009János Flesch Abstract We investigate the problem in which an agent has to find an object that moves between two locations according to a discrete Markov process (Pollock, Operat Res 18 (1970) 883,903). At every period, the agent has three options: searching left, searching right, and waiting. We assume that waiting is costless whereas searching is costly. Moreover, when the agent searches the location that contains the object, he finds it with probability 1 (i.e. there is no overlooking). Waiting can be useful because it could induce a more favorable probability distribution over the two locations next period. We find an essentially unique (nearly) optimal strategy, and prove that it is characterized by two thresholds (as conjectured by Weber, J Appl Probab 23 (1986) 708,717). We show, moreover, that it can never be optimal to search the location with the lower probability of containing the object. The latter result is far from obvious and is in clear contrast with the example in Ross (1983) for the model without waiting. © 2009 Wiley Periodicals, Inc. Naval Research Logistics 2009 [source] Maternal factors associated with the duration of breast feeding in Jeddah, Saudi ArabiaPAEDIATRIC & PERINATAL EPIDEMIOLOGY, Issue 1 2003Sherine Shawky Summary Recently, there has been increasing concern about the decline in breast-feeding pattern in developing countries. The objectives of this study were to document the recent breast-feeding trends in Jeddah during the first year of an infant's life and identify the probable maternal risk factors implicated in breast-feeding cessation. Data were collected from six randomly selected primary health care centres in Jeddah City. All married women with an infant , 12 completed months of age were interviewed, and information on socio-demographic characteristics, breast feeding and contraceptive use were collected. Cox proportional hazard regression model was used to calculate the adjusted odds ratios for the various maternal risk factors related to breast-feeding cessation. A total of 400 women were enrolled in the study. Their mean age at delivery was 28.0 years (SD = 4.1 years). Approximately 40.0% had never attended school, 43.0% had at least five children and 13.8% were smokers. Deliveries by caesarean section were reported by 13.0% of women and contraceptive use by 44.7%, among whom oral contraceptives were the commonest method. Around 94.0% of women ever initially breast fed their infants, and this proportion dropped to 40.0% by the infant's 12th month. Women who delivered by caesarean section (OR = 1.9 [95% CI 1.3, 2.8]P = 0.001) and those who used oral contraceptives (OR = 1.5 [95% CI 1.1, 2.2]P = 0.031) were at higher risk of stopping breast feeding and lower probability of maintaining breast feeding to the 12th month post partum than those who delivered vaginally and did not use oral contraceptives. Breast-feeding practice seems to decline rapidly during the first year of the infant's life. Health care professionals should promote breast-feeding practice as early as the antenatal period. They should also take into consideration the impact of caesarean section deliveries and early oral contraceptive use to avoid their negative impact on breast-feeding practice. [source] Extrathoracic airway responsiveness in children with asthma-like symptoms, including chronic persistent coughPEDIATRIC PULMONOLOGY, Issue 3 2002Ipek Turktas MD Abstract Asthma-like symptoms, including chronic persistent cough, are not always specific for classical asthma. In order to investigate whether assessment of extrathoracic airway hyperresponsiveness (EAHR) during methacholine bronchial challenge helped in the evaluation of pediatric patients with asthma-like symptoms such as chronic cough, we examined 133 consecutive, unselected patients (mean age, 10.06,±,2.16 years) who had neither established asthma nor bronchial obstruction previously. We recorded the forced mid-inspiratory flow (FIF50) as an index of extrathoracic airway narrowing. In addition, a 25% decrease in FIF50 (PD25FIF50) below the cutoff concentration of ,,8 mg/mL methacholine was assumed to indicate EAHR. According to the methacholine response, 81 patients had EAHR, and 41 of them had combined EAHR and bronchial hyperresponsiveness (BHR); 39 patients had only BHR. Airway hyperresponsiveness was not demonstrated in 13 patients and not in any of the control children. When patients with cough as the sole presenting symptom (60.9%) were compared with those with cough and wheeze (20.3%), those with cough alone had a significantly greater probability of having EAHR (OR, 4.16; 95% CI, 1.32,13.13) and a lower probability of having BHR (OR, 0.70; CI, 0.25,1.95) than those with cough and wheeze. Patients with cough, wheeze, and dyspnea (18.8%) had a significantly greater chance of having BHR than those with cough alone (OR, 5.08; CI, 1.55,16.64). Patients with cough and wheeze as compared with those with cough, wheeze, and dyspnea had significantly greater probability of having both EAHR and BHR (OR, 4.71; CI, 1.94,11.47). In order to ascertain the clinical relevance of EAHR, we assessed in the second part of the study whether the effects of treatment of the underlying disease would result in relief of airway hyperresponsiveness. Rhinosinusitis and perennial allergic rhinitis accounted for EAHR in 71 patients, and 34 of them also demonstrated BHR. They received specific therapy for their upper airway diseases for 4 weeks. Compared with values before treatment, FIF50 and forced expiratory volume in 1 sec (FEV1) did not change significantly. The dose of methacholine causing a 20% fall in FEV1 (PD20FEV1) and PD25FIF50 values were significantly increased from 2.40,±,1.39 to 4.22,±,1.13 mg /mL (P,<,0.001) and from 1.03,±,1.75 to 8.71,±,1.21 mg /mL (P,<,0.0001), respectively. We conclude that measurements of EAHR and BHR are the most important ways to evaluate children with asthma-like symptoms, including chronic persistent cough when chest X-rays and pulmonary function tests remain within normal limits. Therefore, empirical treatment is not necessary when these investigations are available. Our results suggest that specific treatment of inflammation in the upper airways reversed persistant cough, and may play an important role in modulating lower airways responsiveness in patients with concomitant BHR. Pediatr Pulmonol. 2002; 34:172,180. © 2002 Wiley-Liss, Inc. [source] Work-related carpal tunnel syndrome in Washington State workers' compensation: Utilization of surgery and the duration of lost workAMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 12 2009William E. Daniell MD Abstract Background Work-related carpal tunnel syndrome (CTS) is a leading cause of lengthy disability. Methods This population-based retrospective cohort study used Washington State workers' compensation claims for CTS to characterize associations between utilization of CTS surgery and duration of lost work. The sample included all claims (n,=,8,224) filed during 1990,1994 (followed through 2000) and receiving lost-work compensation. Results Sixty-four percent of studied workers had CTS surgery. Among workers with >1 month of lost work, the total duration was much shorter when workers had surgery, versus those who did not (median 4.3 and 6.2 months, respectively; P,<,0.001); there was no difference when disability extended >6 months. When workers had surgery, disability was less likely to end before 6 months if non-CTS conditions were present, surgery occurred >3 months after claim filing, or employment was in an industry with high incidence of CTS; disability was more likely to end if the diagnosing provider and operating surgeon had higher CTS claims volume. Physical and rehabilitation medicine services were associated with lower probability of returning to work, with or without surgery. Conclusions There is a need to scrutinize the role of surgery and physical-rehabilitation medicine modalities in the management of CTS covered by workers' compensation. The findings suggest disability can be minimized by establishing the CTS diagnosis as early as possible and, if surgery is appropriate, conducting surgery without substantial delay and maximizing post-operative efforts to facilitate return to work. Use of surgery >6 months after filing should be considered with great caution. Am. J. Ind. Med. 52:931,942, 2009. © 2009 Wiley-Liss, Inc. [source] The Course and Quality of Intimate Relationships Among Psychologically Distressed MothersAMERICAN JOURNAL OF ORTHOPSYCHIATRY, Issue 1 2010Lauren M. Papp The longitudinal course and quality of intimate relationships were tested in relation to maternal depressive symptoms in a sample of 1,275 families from the National Institute of Child Health and Human Development Study of Early Child Care and Youth Development. Assessments of mothers' intimate relationship status, intimate relationship quality, and depressive symptoms were obtained on 11 occasions from the birth of a child through age 15. Consistent with predictions, results from hierarchical linear models indicated that maternal depressive symptoms over time were associated with a lower probability of being married and lower levels of relationship quality. The strength of the association between relationship quality and depression was stronger than the linkage between relationship course and depression. Sociodemographic characteristics (e.g., mother age, child gender, ethnicity) were more predictive of trajectories of relationship course than relationship quality. Findings are discussed in terms of efforts to prevent and treat the longitudinal interplay between poor intimate relationship functioning and partners' psychopathology and its implications for the overall health and well-being of parents, couples, and children. [source] The Potential Benefits of Remaining in School on the Long,Term Mental Health Functioning of Physically and Sexually Abused Children: Beyond the Academic DomainAMERICAN JOURNAL OF ORTHOPSYCHIATRY, Issue 1 2006Simon Williams PhD Community,based population survey data were used to explore whether remaining in school, independent of achievement status, was associated with lower rates of psychopathology in adulthood among participants self,reporting exposure to child physical and/or sexual abuse. Remaining in school, independent of one's achievement status, was significantly associated with a lower probability of experiencing externalizing but not internalizing disorders. Theoretical and educational implications of these results are discussed. [source] Housing Tenure, Job Mobility and Unemployment in the UK,THE ECONOMIC JOURNAL, Issue 527 2008Harminder Battu This article examines the effects of housing tenure on individuals' job and unemployment durations in the UK. We examine job to job transitions and transitions from unemployment. We take account of whether or not the arrival of a job was synonymous with a non-local residential move, tenure endogeneity and unobserved heterogeneity. We find that home-ownership is a constraint for the employed and public renting is more of a constraint for the unemployed. Employed home-owners have a lower transition into employment with a distant move and unemployed public renters have a lower probability of gaining employment in more distant labour markets. [source] Investment and Finance in de novo private firms: Empirical Results from the Czech Republic, Hungary and PolandTHE ECONOMICS OF TRANSITION, Issue 1 2000Andrzej Bratkowski In this paper we use a survey of 281 Czech, Hungarian and Polish newly-established small private firms in order to shed some light on the constraints these firms face in the credit market. The results of our survey show that imperfections in capital markets in Central European economies do not seem to actually inhibit the growth of new private firms. Credit markets do exist for de novo private firms in the three Central European transition economies studied, and they provide quite a large amount of financing from an early stage of the existence of firms. Financial intermediation works reasonably well as far as de novo private firms are concerned: loss-making de novo firms have a lower probability of getting credit than profitable ones. Banks protect themselves against the risk of a deteriorating pool of borrowers by requiring collateral for their loans. We do not find convincing evidence concerning the existence of adverse selection. Loss-making firms are not ready to pay higher interest rates than profitable firms and are not more likely to ask for credit than profitable firms. [source] A Multicenter Study of Valganciclovir Prophylaxis up to Day 120 in CMV-Seropositive Lung Transplant RecipientsAMERICAN JOURNAL OF TRANSPLANTATION, Issue 5 2009V. Monforte Seventy-six cytomegalovirus (CMV)-seropositive lung transplant recipients receiving valganciclovir (900 mg/day) for CMV prophylaxis were compared with a group of 87 patients receiving oral ganciclovir (3000 mg/day). Prophylaxis was administered to day 120 post-transplantation and follow-up was 1 year. In addition, a study was conducted on risk factors for CMV infection/disease. CMV disease incidence was 7.9% and 16.1% for valganciclovir and oral ganciclovir, respectively (p = 0.11). Patients receiving valganciclovir had fewer viral syndromes (2.6% vs. 11.5%, p < 0.05), a similar rate of tissue-invasive disease (5.2% vs. 4.6%, p = ns), longer time-to-onset of CMV infection/disease (197.5 vs. 155.2 days, p < 0.05), and a lower probability of infection/disease while on prophylaxis (1.3% vs. 12.6%, p < 0.01). Nonetheless, leukopenia incidence was higher with valganciclovir (15.8% vs. 2.3%, p < 0.01), as was the need for treatment withdrawal due to adverse effects (11.8% vs. 1.1%, p < 0.01). CMV infection was similar in both groups (32.9% vs. 34.5%). Induction therapy with basiliximab and glucocorticosteroid treatment were independent risk factors for developing CMV infection/disease. In conclusion, valganciclovir prophylaxis results in a low incidence of CMV disease in lung transplant recipients and appears more effective than oral ganciclovir. Despite the comparatively higher incidence of adverse events with valganciclovir, the drug can be considered safe for prophylaxis. [source] Short-term differences in animal assemblages in patches formed by loss and growth of habitatAUSTRAL ECOLOGY, Issue 5 2010PETER I. MACREADIE Abstract Ecological theory predicts that habitat growth and loss will have different effects on community structure, even if they produce patches of the same size. Despite this, studies on the effects of patchiness are often performed without prior knowledge of the processes responsible for the patchiness. We manipulated artificial seagrass habitat in temperate Australia to test whether fish and crustacean assemblages differed between habitats that formed via habitat loss and habitat growth. Habitat loss treatments (originally 16 m2) and habitat growth treatments (originally 0 m2) were manipulated over 1 week until each reached a final patch size of 4 m2. At this size, each was compared through time (0,14 days after manipulation) with control patches (4 m2 throughout the experiment). Assemblages differed significantly among treatments at 0 and 1 day after manipulation, with differences between growth and loss treatments contributing to most of the dissimilarity. Immediately after the final manipulation, total abundance in habitat loss treatments was 46% and 62% higher than controls and habitat growth treatments, respectively, which suggests that animals crowded into patches after habitat loss. In contrast to terrestrial systems, crowding effects were brief (,1 day), signifying high connectivity in marine systems. Growth treatments were no different to controls, despite the lower probability of animals encountering patches during the growth phase. Our study shows that habitat growth and loss can cause short-term differences in animal abundance and assemblage structure, even if they produce patches of the same size. [source] Effects of tail autotomy on survival, growth and territory occupation in free-ranging juvenile geckos (Oedura lesueurii)AUSTRAL ECOLOGY, Issue 4 2006JONATHAN K. WEBB Abstract Many animals autotomize their tails to facilitate escape from predators. Although tail autotomy can increase the likelihood of surviving a predatory encounter, it may entail subsequent costs, including reduced growth, loss of energy stores, a reduction in reproductive output, loss of social status and a decreased probability of survival during subsequent encounters with predators. To date, few studies have investigated the potential fitness costs of tail autotomy in natural populations. I investigated whether tail loss influenced survival, growth and territory occupation of juvenile velvet geckos Oedura lesueurii in a population where predatory snakes were common. During the 3-year mark,recapture study, 32% of juveniles voluntarily autotomized their tails when first captured. Analysis of survival using the program mark showed that voluntary tail autotomy did not influence the subsequent survival of juvenile geckos. Survival was age-dependent and was higher in 1-year-old animals (0.98) than in hatchlings (0.76), whereas recapture probabilities were time-dependent. Growth rates of tailed and tailless juveniles were very similar, but tailless geckos had slow rates of tail regeneration (0.14 mm day,1). Tail autotomy did not influence rock usage by geckos, and both tailed and tailless juveniles used few rocks as diurnal retreat sites (means of 1.64 and 1.47 rocks, respectively) and spent long time periods (85 and 82 days) under the same rocks. Site fidelity may confer survival advantages to juveniles in populations sympatric with ambush foraging snakes. My results show that two potential fitness costs of tail autotomy , decreased growth rates and a lower probability of survival , did not occur in juveniles from this population. However, compared with juveniles, significantly fewer adult geckos (17%) voluntarily autotomized their tails during capture. Because adults possess large tails that are used for lipid storage, the energetic costs of tail autotomy are likely to be much higher in adult than in juvenile O. lesueurii. [source] Seed Dispersal of a High Quality Fruit by Specialized Frugivores: High Quality Dispersal?,BIOTROPICA, Issue 2 2000Daniel G. Wenny ABSTRACT Dispersal quality, as estimated by the cumulative effects of dispersal, germination, seed predation, and seedling survival, was examined for Beilschmiedia pendula (Lauraceae) in Monteverde, Costa Rica. I determined the pattern of dispersal by finding seeds deposited by birds, protected the seeds from seed predators with cages to assess germination and seedling survival, and examined seed predation rates with marked seeds. Seed predation, germination, and seedling survival were compared between seeds naturally dispersed by birds and seeds placed at randomly located sites. Approximately 70 percent of seeds dispersed by birds (N= 244) were deposited <10 m from crown edges of fruiting B. pendula trees, although some seeds were dispersed at least 70 m away. Larger seeds were more likely to be dispersed under or close to the parent trees, and larger seeds produced larger seedlings. Seed size was not correlated directly with seedling survival, but larger seedlings at three months were most likely to survive one year. Seed predation by mammals and insects and seedling mortality due to fungal pathogens were concentrated beneath the crowns of parent trees. Seedlings and saplings were more abundant beneath fruiting B. pendula trees, but individuals farther away were taller on average. Thus, dispersal is beneficial for B. pendula, but such benefits appear most pronounced at a small spatial scale; seeds dispersed >30 m from the crown edges actually had a lower probability of survival than those dispersed 10,20 m. Only 10 percent of B. pendula. seeds received high-quality dispersal in terms of landing in the zone with the highest per seed probability of seedling survival 10,20 m from parental crowns. RESUMEN La calidad de dispersión, estimado del efecto acurnulativo de dispersión, germinación, predación de semillas, y sobrevivencia de plantulas fue examinada por Beikcbmiedia pendula (Lauracea) en Monteverde, Costa Rica. Determinté el partén de disperstón, encontrando semillas defecadas o regurgitadas por aves, protegi semillas de predatores con jaulas para determinar germinación y sobrevivencia de plantulas, y examiné la proporción de predación de semillas con semillas marcadas. Predación de semillas, germinación y sobrevivencia de plantulas fueron comparadas con semillas dispersadas naturalmente por aves y con semillas localizadas en lugares al azar. Aproximadamente 70 porcento de las semillas dispersadas por aves (N = 244) fueron depositadas cerca de 10 mdel horde de la corona de árboles en fruto de B. pendula, aunque algunas semillas fueron dispersadas hasta 70 m mas lejos. Semillas grandes tuvieron la tendencia de ser dispersadas debajo o cerca del Brbol parental, y semillas grandes produjeron plantulas grandes. El tamaño de la semilla no estaba correlacionada directamente con sobrevivencia de plantulas, pero plantulas grandes a 3 mesa tuvieron la tendencia de sobrevivir. Predación de semillas por los roedores y insectos, y mortalitad de plantulas por hongos patogtnicos fueron lo mas comun debajo de la corona de los árboles parentales. Plantulas y arbolillos fueron mós abundantes debajo de drboles en fruto de B. pendula, pero individuos distantes fueron en promedio más altos. Dispersión es favorable para B. pendula, pero estos beneficios aparentan ser más ptonunciados a una escala espacial menot; semillas dispersadas más de 30 m del horde de la corona en realidad tienen una probabilidad menor de sobrevivencia que las que son dispersadas entre 10,20 m. Solamente 10 porcento de las seniillas de B. pendula recibieron despersión de calidad alta en terminos de aterrizar en una zona con la más alta probabilidad de sobrevivencia de plantulas entre 10,20 m de la corona parental. [source] | |||||||||||||||||||