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11.
We add two cases of prenatally diagnosed late-onset isolated cystic hygroma to the eight cases reported previously in the English literature. The obstetrical significance, management, and outcome of this entity are reviewed. A retrospective study of late-onset isolated cystic hygromas delivered in one medical centre between 1978 and 1992 was made. The medical records of these newborns served as the basis of the present report. A Medline search of the English literature was carried out. Over a period of 15 years, we observed 11 cases of late-onset congenital isolated cystic hygroma, two of whom had prenatal sonographic diagnosis. In one case, a Caesarean section was performed due to a huge lesion. All cases underwent surgical excision with a favourable outcome. Of the eight prenatally diagnosed cases reported previously, one died at birth due to inability to ventilate and two required a tracheostomy. Late-onset isolated cystic hygroma should be differentiated from the early-onset nuchal cystic hygroma. The differential diagnosis is important, as late-onset isolated cystic hygroma does not require any prenatal intervention, but special awareness during labour and Caesarean section in extreme cases. Transport to a perinatal centre with expert neonatal, respiratory, and paediatric surgical care is recommended. The prognosis in general is favourable.  相似文献   
12.
New business formation is a formidable and daunting task, which may require personal perseverance and self‐efficacy. If this is indeed the case, will entrepreneurs and non‐entrepreneurs differ on such attributes? Also, if high levels of perseverance and self‐efficacy help entrepreneurs to overcome setbacks, snags, and obstacles, do these positive attributes co‐occur with significant personal costs, such as the tendency to experience regretful thinking? This study uses a random sample of 217 patent inventors in the medical industry (surgery devices) to address these questions. Results indicate that entrepreneurs score significantly higher on self‐efficacy and on two distinct aspects of perseverance—perceived control over adversity and perceived responsibility regarding outcome of adversity—than did non‐entrepreneurs. Also, although entrepreneurs report the same number of regrets, their regrets are stronger and are qualitatively different from those reported by non‐entrepreneurs. These findings suggest that perseverance and self‐efficacy do indeed co‐occur with regretful thinking. Finally, post hoc analysis reveals that the higher the overall perseverance scores of patent inventors, the higher their annual earnings. We conclude by examining the implications for theory, researcher, and practice. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
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14.
Genetic diversity within species represents a fundamental yet underappreciated level of biodiversity. Because genetic diversity can indicate species resilience to changing climate, its measurement is relevant to many national and global conservation policy targets. Many studies produce large amounts of genome-scale genetic diversity data for wild populations, but most (87%) do not include the associated spatial and temporal metadata necessary for them to be reused in monitoring programs or for acknowledging the sovereignty of nations or Indigenous peoples. We undertook a distributed datathon to quantify the availability of these missing metadata and to test the hypothesis that their availability decays with time. We also worked to remediate missing metadata by extracting them from associated published papers, online repositories, and direct communication with authors. Starting with 848 candidate genomic data sets (reduced representation and whole genome) from the International Nucleotide Sequence Database Collaboration, we determined that 561 contained mostly samples from wild populations. We successfully restored spatiotemporal metadata for 78% of these 561 data sets (n = 440 data sets with data on 45,105 individuals from 762 species in 17 phyla). Examining papers and online repositories was much more fruitful than contacting 351 authors, who replied to our email requests 45% of the time. Overall, 23% of our email queries to authors unearthed useful metadata. The probability of retrieving spatiotemporal metadata declined significantly as age of the data set increased. There was a 13.5% yearly decrease in metadata associated with published papers or online repositories and up to a 22% yearly decrease in metadata that were only available from authors. This rapid decay in metadata availability, mirrored in studies of other types of biological data, should motivate swift updates to data-sharing policies and researcher practices to ensure that the valuable context provided by metadata is not lost to conservation science forever.  相似文献   
15.
A systematic review was performed to evaluate the association between environmental exposures to polyhalogenated aromatic hydrocarbons (PHAHs) and organochlorine (OC) pesticides and the risk for type 2 diabetes (T2D). Searches of EMbase, Google Scholar, Medline, and Scopus were performed. Reports were included if they were original human studies whose design included a control group and if the sample size was larger than 10 participants per group. The articles were excluded if the type of diabetes was unknown or Type 1. Odds ratios (OR), 95% confidence intervals (CI), and modified Naranjo scores for the effects of environmental contaminants were determined for each study. Of the 35 eligible studies, six were included in the meta-analysis; these focused specifically on 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Meta-analysis of these studies showed no significant increased OR for the development of T2D from exposure to TCDD. However, subgroup analysis showed significant elevated OR for the development of T2D if exposure is repeated and accompanied by exposure to other persistent pesticides (OR?=?1.48; 1.10–1.90) but a decreased odds for T2D with exposure resulting from accidental exposure (OR?=?0.46; 0.39–0.52). Our results suggest that there are significant risks of developing T2D in populations with recurring exposures to TCDD in concert with other persistent chlorinated pesticides. A mean Naranjo score of 2.0 was determined for all 35 articles; this score was 2.5 when examining only TCDD studies and 2.1 when examining studies that looked only at T2D. Each of these Naranjo scores suggests a possible association between the prevalence of T2D and exposure to PHAHs or OC pesticides.  相似文献   
16.
ABSTRACT: A preliminary field experiment was conducted for trickle irrigation of winter wheat raised for grain production under arid conditions. Treated waste water was applied for trickle irrigation via a trickle system. Mean total amount of effluent applied was about 5700 m3/ha. In one of the experimental treatments, which was irrigated once a week, a grain yield of over 10,000 kg/ha was obtained, whereas in the other treatments the yields were about 8,500 kg/ha, which are above the mean yield obtained under sprinkler irrigation.  相似文献   
17.
Many countries in sub‐Saharan Africa have liberalized markets to improve efficiency and enhance market linkages for smallholder farmers. The expected positive response by the private sector in areas with limited market infrastructure has however been very limited. The functioning of markets is constrained by high transaction costs and coordination problems along the production‐to‐consumption value chain. New kinds of institutional arrangements are needed to reduce these costs and fill the vacuum left when governments withdrew from markets in the era of structural adjustments. One of these institutional innovations has been the strengthening of producer organizations and formation of collective marketing groups as instruments to remedy pervasive market failures in rural economies. The analysis presented here with a case study from eastern Kenya has shown that marketing groups pay 20–25% higher prices than other buyers to farmers while participation was also positively correlated with adoption of improved dryland legume varieties, crops not targeted by the formal extension system. However the effectiveness of marketing groups is undermined by external shocks and structural constraints that limit the volume of trade and access to capital and information, and require investments in complementary institutions and coordination mechanisms to exploit scale economies. Successful groups have shown high levels of collective action in the form of increased participatory decision making, member contributions and initial start‐up capital. Failure to pay on delivery, resulting from lack of capital credit, is a major constraint that stifles competitiveness of marketing groups relative to other buyers. These findings call for interventions that improve governance and participation; mechanisms for improving access to operating capital; and effective strategies for risk management and enhancing the business skills of farmer marketing groups.  相似文献   
18.
Poverty studies have demonstrated that a group’s ability to escape poverty is largely dependent on the types of assets that the group’s members possess. A major claim that has been asserted with limited empirical evidence in the asset literature is the gender disparity dichotomy. Using rural Ghana as a case study, we assess the asset levels of farm households from a gender perspective. In doing so, we theorized and empirically tested assets on case bases. A household questionnaire survey was used to collect data from two hundred households in the Fanteakwa district of eastern Ghana. An asset index was used to compute the asset levels, while Kruskal–Wallis statistics was employed to compare the significance of the temporal changes. The results show a minimum level of asset endowment. Natural, social and financial assets were the three most endowed assets, with physical and human assets being the least. A gender analysis shows no significant difference, even though the levels of assets for the female-headed households were slightly higher than those of the male-headed households. However, the study found a 22.7% increment in the accumulation of financial assets among the female-headed households over the last 5 years compared to a 9.3% decrement in the same assets for their male-headed counterparts. Applying our theory, the results present an unbalanced and unstable asset situation among the household heads. We call for improvement, in physical and human assets. The overall study results imply an improvement in gender-asset accessibility in the context of rural Ghana.  相似文献   
19.
Environmental Science and Pollution Research - Rapid population growth and poor waste management practice are among the main drivers of plastic pollution in modern times, thus making Africa a...  相似文献   
20.
This paper attempts to provide an empirical basis for planning the optimisation of public outdoor recreational potential in Benin City, Nigeria. The study is seen as a partial analysis in that it considers only the deferred component of demand, and only with public recreational facilities. It identifies a mismatch between demand for and provision of facilities, due to an inadequate planning system.  相似文献   
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