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991.
The taller people are, the more money they tend to earn. This phenomenon is widely known as the height premium. However, it is not yet known whether the height premium is universal, or whether it varies by context. To that end, a systematic review of the literature was performed. Five databases were searched until August 2020. Ultimately, a list of 42 studies were included in a narrative synthesis, and 17 studies were included in a meta-analysis. Based on the meta-analysis, we found evidence that the height premium varied by context: the height premium was smaller in the U.S. and Australia, and larger in Latin America and Asia. Within geographies, there appeared to be a larger height premium for men than for women. Cultural factors, labor market structures and biology may play a role in determining the strength of the height premium.  相似文献   
992.
No tillage (NT) has been proposed as a practice to reduce the adverse effects of tillage on contaminant (e.g., sediment and nutrient) losses to waterways. Nonetheless, previous reports on impacts of NT on nitrate ( NO 3 ) leaching are inconsistent. A global meta-analysis was conducted to test the hypothesis that the response of NO 3 leaching under NT, relative to tillage, is associated with tillage type (inversion vs non-inversion tillage), soil properties (e.g., soil organic carbon [SOC]), climate factors (i.e., water input), and management practices (e.g., NT duration and nitrogen fertilizer inputs). Overall, compared with all forms of tillage combined, NT had 4% and 14% greater area-scaled and yield-scaled NO 3 leaching losses, respectively. The NO 3 leaching under NT tended to be 7% greater than that of inversion tillage but comparable to non-inversion tillage. Greater NO 3 leaching under NT, compared with inversion tillage, was most evident under short-duration NT (<5 years), where water inputs were low (<2 mm day−1), in medium texture and low SOC (<1%) soils, and at both higher (>200 kg ha−1) and lower (0–100 kg ha−1) rates of nitrogen addition. Of these, SOC was the most important factor affecting the risk of NO3 leaching under NT compared with inversion tillage. Globally, on average, the greater amount of NO3 leached under NT, compared with inversion tillage, was mainly attributed to corresponding increases in drainage. The percentage of global cropping land with lower risk of NO3 leaching under NT, relative to inversion tillage, increased with NT duration from 3 years (31%) to 15 years (54%). This study highlighted that the benefits of NT adoption for mitigating NO 3 leaching are most likely in long-term NT cropping systems on high-SOC soils.  相似文献   
993.
Seed dispersal is a fundamental process that is highly threatened by the rapid decline of large-bodied frugivores worldwide. The Brazilian Cerrado, the largest savanna in the world, represents an ideal site for investigating seed dispersal because of its biodiversity, environmental challenges, and knowledge shortfalls. We performed a systematic literature review to analyze the seed dispersal network in the Cerrado and the potential impacts of the defaunation of large-bodied frugivores on it. We considered network metrics, calculated the defaunation index of the frugivore assemblage, and compared traits among different fruit-sized plants and their respective dispersers in the network. We retrieved 1565 interactions involving 193 plant species and 270 animal species. Results show that the Cerrado seed dispersal network is slightly nested and considerably modular, dominated by small- to medium-sized generalist species, such as passerines, marsupials, and mesocarnivores. Nonetheless, large-bodied frugivores like the lowland tapir have a key role in the network due to their great foraging and network integration capacity. The Cerrado frugivore assemblage is moderately defaunated, with possible effects in its interactions with large-fruited plants. The Cerrado's defaunation and functional loss of large vertebrates deserve urgent attention to further understand the impacts on seed dispersal mechanisms and ecosystem functioning.  相似文献   
994.
《Endocrine practice》2023,29(5):398-407
ObjectiveThe obesity epidemic is a global health concern with Asian countries facing one of the most rapid rises in obesity rates. However, given the underwhelming long-term efficacy of weight loss strategies, especially in Asia, this review aimed to explore barriers and facilitators to weight management of patients with overweight and obesity in Asia.MethodsMedline, CINAHL, PsycINFO, and Web of Science were searched for articles discussing barriers and facilitators of treatment to obesity from the perspectives of both health care professionals (HCPs) and patients. Qualitative and mixed method studies from Asia were included. Key quotes were extracted, coded, and thematically analyzed according to the methodology of Thomas and Harden.ResultsA total of 26 articles were included in this review. From patient perspectives, 3 main themes were identified: factors influencing poor eating behavior, inhibiting lifestyle modifications, and facilitating lifestyle modifications. Patients highlighted several barriers including the lack of social support, physiologic limitations to exercise, and low health literacy. Rigid sociocultural norms and lack of accessible health care services, exercise facilities, and healthy food exacerbated the barriers. Facilitators to lifestyle modifications consisted of strong support systems and high health literacy. HCPs agreed that low health literacy, lack of social support, and patient motivation impeded patients’ weight loss attempts but were unaware of the other barriers they faced.ConclusionThere are discrepancies between ideas of barriers and facilitators of HCPs and patients. A mixture of population level, primary care, and personal interventions are required to address this disparity, and enhanced health literacy can improve weight loss outcomes.  相似文献   
995.
发酵菌株的改良在发酵工业生产上通常是一项非常重要的内容,而传统的驯化模式周期长、效率低、稳定性差且成本高,很难满足工业化快速生产的要求。规律成簇间隔短回文重复Cas(Clustered Regularly Interspaced Short Palindromic Repeats/Cas,CRISPR/Cas)是细菌及古生菌中的一种适应性免疫系统,在此系统上改进的基因编辑技术能实行RNA导向的DNA精准编辑。因而利用CRISPR/Cas基因编辑技术对菌株的快速构建和优化,是一条快速获得高产菌株的新途径。本文综述了CRISPR/Cas系统组成、工作原理、分类以及该技术在发酵菌株上的应用研究进展,并探索了该技术存在的问题以及目前的解决办法,最后对CRISPR/Cas技术在发酵工程上的潜力进行了展望。  相似文献   
996.
Poecilobdella viridis was used to study the variations in the biochemical parameters: body protein, glycogen and water, following warm (32.0° ± 0.5°C) and cold (10.0° ± 0.5°C) acclimation for 5, 10, 15 and 30 days. The percentage of glycogen decreased significantly (p < 0.05) during both warm and cold acclimation whereas the protein percentage increased significantly (p < 0.05). The percentage of water was significantly (p < 0.05). reduced during both acclimation processes. Ecophysiological significance of these alterations to leeches, in counteracting the ambient thermal fluxes, has been briefly discussed.  相似文献   
997.
998.
《Cancer epidemiology》2014,38(6):647-653
BackgroundSmokeless tobacco is a possible risk factor for developing pancreatic adenocarcinoma. This systematic review addressed the question: Is there an association between smokeless tobacco use and pancreatic adenocarcinoma diagnosis?MethodsFive electronic databases, grey literature, and citations of relevant articles were searched to identify studies. Six researchers double-reviewed records for inclusion in the review. The information extracted from these studies was selected using criteria outlined in the Newcastle–Ottawa Quality Assessment Scale for observational studies. A qualitative synthesis of included studies was performed.ResultsThe search of electronic databases resulted in a total of 1747 citations. Eleven studies met the inclusion criteria for this review, including three cohort studies, seven case control studies and one study that pooled data from multiple case-control studies. Studies were heterogeneous in their assessment of exposure intensity and ascertainment of outcomes. Quality of the studies varied. Existing investigations of the association of interest appear to exhibit several types of biases including selection bias, information bias and bias in the analysis.ConclusionThe association between smokeless tobacco use and pancreatic adenocarcinoma is inconclusive. More definitive conclusions regarding this relationship await the results of more methodologically rigorous epidemiologic studies.  相似文献   
999.
1000.
Abstract

The genus Ctenopseustis Meyrick (Tortricinae: Archipini) is reviewed. The species C. fraterna Philpot, 1930 and C. servana Walker, 1863 are reinstated, and the concept of C. obliquana (Walker, 1863) is redefined. Synonymies are given for each species, and characteristics are described and illustrated.  相似文献   
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