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Agriculture is being challenged to provide food, and increasingly fuel, for an expanding global population. Producing bioenergy crops on marginal lands—farmland suboptimal for food crops—could help meet energy goals while minimizing competition with food production. However, the ecological costs and benefits of growing bioenergy feedstocks—primarily annual grain crops—on marginal lands have been questioned. Here we show that perennial bioenergy crops provide an alternative to annual grains that increases biodiversity of multiple taxa and sustain a variety of ecosystem functions, promoting the creation of multifunctional agricultural landscapes. We found that switchgrass and prairie plantings harbored significantly greater plant, methanotrophic bacteria, arthropod, and bird diversity than maize. Although biomass production was greater in maize, all other ecosystem services, including methane consumption, pest suppression, pollination, and conservation of grassland birds, were higher in perennial grasslands. Moreover, we found that the linkage between biodiversity and ecosystem services is dependent not only on the choice of bioenergy crop but also on its location relative to other habitats, with local landscape context as important as crop choice in determining provision of some services. Our study suggests that bioenergy policy that supports coordinated land use can diversify agricultural landscapes and sustain multiple critical ecosystem services.In agricultural landscapes, balancing the provisioning of food and energy with maintenance of biodiversity and ecosystem functions is a global challenge. To avoid impacts on food production, attention is increasingly being focused on the potential for marginal lands to support bioenergy production (1). Marginal lands, those suboptimal for food production, may consist of relatively small areas within generally productive landscapes or larger regions where conditions generally limit crop productivity. However, there is increasing recognition that these lands are already performing a variety of useful functions, and their conversion to bioenergy cropping could reduce these services. For example, in the north central United States, rising commodity prices are predicted to bring marginal croplands—including Conservation Reserve Program lands—into annual crop production with negative impacts on wildlife habitat and water quality (2, 3). With 2013 corn plantings at recent record highs (4) and new reports of grassland and wetland conversion to cropland (5, 6), this may be occurring already.An alternative to annual cropping is conversion of marginal croplands to perennial, cellulosic crops for bioenergy. Although current US biofuel production centers on grain ethanol derived from annual monocultures of maize (Zea mays), this situation could change with full implementation of the 2007 US Energy Independence and Security Act (7), which calls for increased production of cellulosic biofuels. In the Midwest United States, perennial grasses and forbs grown on marginal lands could provide up to 25% of national targets for cellulosic biofuel, with substantial greenhouse gas (GHG) benefits (8). Moreover, increasing the area of perennial cover on the landscape is predicted to positively affect a diverse array of organisms and ecological functions (911), leading to important synergies that have not yet informed the ongoing bioenergy debate. Here we provide the most comprehensive empirical evaluation of this hypothesis to date, reporting data that elucidate the impacts of different bioenergy cropping systems on a wide variety of organisms and the ecosystem functions they perform.Previous studies have examined the ability of select bioenergy crops to support specific taxa (12) or individual services such as energy production (13) or GHG mitigation (14), without consideration of the tradeoffs or synergies that can arise when considering entire suites of organisms and ecosystem functions. We report on a unique multidisciplinary study of matched sets of organisms and ecosystem services and show that perennial grass energy crops (switchgrass, Panicum virgatum, and mixed prairie plantings) synergistically enhance diversity of a variety of organisms and levels of the services they provide. We further quantify the importance of landscape context on service provisioning, suggesting that policy supporting intentional design of bioenergy landscapes could increase sustainability of both food and energy production.  相似文献   
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Goubert L  Eccleston C  Vervoort T  Jordan A  Crombez G 《Pain》2006,123(3):254-263
Numerous studies have found evidence for the role of catastrophizing about pain in adjustment to pain in both adults and children. However, the social context influencing pain and pain behaviour has been largely ignored. Especially in understanding the complexities of childhood pain, family processes may be of major importance. In line with the crucial role of pain catastrophizing in explaining adjustment and disability in adults and children, this study investigates the role of parental catastrophic thinking about their child's pain in explaining child disability and parental distress. To study parental catastrophizing, a parent version of the Pain Catastrophizing Scale (PCS-P) was developed. An oblique three-factor structure emerged to best fit the data in both a sample of parents of schoolchildren (N=205) and in a sample of parents of children with chronic pain (N=107). Moreover, this three-factor structure was found to be invariant across both parent samples. Further, in the clinical sample, parents' catastrophic thinking about their child's pain had a significant contribution in explaining (a) childhood illness-related parenting stress, parental depression and anxiety, and (b) the child's disability and school attendance, beyond the child's pain intensity.  相似文献   
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Objectives This study sought to explore how sexual minority women (SMW) and heterosexual women compare in terms of reproductive history, with a particular focus on examining within-group differences among SMW. Methods Women were predominantly recruited through consecutive sampling during presentation for prenatal care in Toronto Canada, and Massachusetts, USA. In total, 96 partnered pregnant women (62 SMW, 34 heterosexual) completed an internet survey during 2013-2015. Results We found few significant differences in reproductive history outcomes when comparing SMW and heterosexual groups. However, when we compared male-partnered SMW to female-partnered SMW, we found potentially important differences in rates of miscarriage and pregnancy complications, indicating that partner gender may be an important contributor to differences in reproductive history among SMW. Conclusions for Practice These findings highlight the need to recognize the unique health risks with which male-partnered SMW may present. Considering that this group is often invisible in clinical practice, the findings from this exploratory study have important implications for providers who treat women during the transition to parenthood. Future research should further examine the differences in social and health access within larger samples of SMW groups, as well as seek to understand the complex relationships between sexual identity and perinatal health for this understudied group of women.

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Nerve and blood vessel ingrowth during intervertebral disc degeneration, is thought to be a major cause of low back pain, however the regulation of this process is poorly understood. Here, we investigated the expression and regulation of a subclass of axonal guidance molecules known as the class 3 semaphorins, and their receptors; plexins and neuropilins within human NP tissue and their regulation by pro-inflammatory cytokines. Importantly this determined whether semaphorin expression was associated with the presence of nerves and blood vessels in tissues from human intervertebral discs. The study demonstrated that semaphorin3A, 3C, 3D, 3E and 3F and their receptors were expressed by native NP cells and further demonstrated their expression was regulated by IL-1β but to a lesser extent by IL-6 and TNFα. This is the first study to identify sema3C, sema3D and their receptors within the nucleus pulposus of intervertebral discs. Immunopositivity shows significant increases in semaphorin3C, 3D and their receptor neuropilin-2 in degenerate samples which were shown to contain nerves and blood vessels, compared to non-degenerate samples without nerves and blood vessels. Therefore data presented here suggests that semaphorin3C may have a role in promoting innervation and vascularisation during degeneration, which may go on to cause low back pain.  相似文献   
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Measurement of body composition to assess health risk and prevention is expanding. Accurate portable techniques are needed to facilitate use in clinical settings. This study evaluated the accuracy and repeatability of a portable ultrasound (US) in comparison with a four‐compartment criterion for per cent body fat (%Fat) in overweight/obese adults. Fifty‐one participants (mean ± SD; age: 37·2 ± 11·3 years; BMI: 31·6 ± 5·2 kg m?2) were measured for %Fat using US (GE Logiq‐e) and skinfolds. A subset of 36 participants completed a second day of the same measurements, to determine reliability. US and skinfold %Fat were calculated using the seven‐site Jackson–Pollock equation. The Wang 4C model was used as the criterion method for %Fat. Compared to a gold standard criterion, US %Fat (36·4 ± 11·8%; P = 0·001; standard error of estimate [SEE] = 3·5%) was significantly higher than the criterion (33·0 ± 8·0%), but not different than skinfolds (35·3 ± 5·9%; P = 0·836; SEE = 4·5%). US resulted in good reliability, with no significant differences from Day 1 (39·95 ± 15·37%) to Day 2 (40·01 ± 15·42%). Relative consistency was 0·96, and standard error of measure was 0·94%. Although US overpredicted %Fat compared to the criterion, a moderate SEE for US is suggestive of a practical assessment tool in overweight individuals. %Fat differences reported from these field‐based techniques are less than reported by other single‐measurement laboratory methods and therefore may have utility in a clinical setting. This technique may also accurately track changes.  相似文献   
10.
PurposeThis study sought to compare sperm DNA fragmentation (SDF) in semen specimens after 3 days and then after 3 h of abstinence in men presenting for initial infertility evaluation.MethodsA prospective cohort study of 112 men undergoing their first semen analysis as part of an infertility work-up was conducted. All participants presented with 3 days of abstinence for a semen analysis and DNA-fragmentation test. Both tests were repeated on a second sample collected 3 h after the first ejaculation. DNA-fragmentation was evaluated with the halo test by one of two technicians blinded to duration of abstinence. Variables analyzed include ejaculate volume, sperm concentration and motility, smoking status, cannabis use, initial specimen DNA fragmentation, and use of sperm-directed anti-oxidant formulations.ResultsAmong all subjects, DNA fragmentation improved in the 3-h abstinence specimen (34.6 ± 19.4% vs. 23.7 ± 16.0%, p = 0.0001). Among subjects with high DNA fragmentation (> 35%) on the initial specimen, 55% improved into the normal range. Semen volume and sperm concentration decreased (3.1 ± 3.3 ml vs. 1.9 ± 0.8 ml, p < 0.01 and 41 ± 39 vs. 32 ± 31 (millions/ml), p = 0.01), while progressive motility tended to increase. Fifty-eight subjects demonstrated ≥ 30% improvement in SDF in the second specimen as compared to the first. Factors found to correlate with > 30% improvement in DNA fragmentation in the 3-h abstinence specimen compared to 3 days were younger age and use of anti-oxidants.ConclusionHigh SDF can often be managed with a second ejaculation 3 h after the first in infertile couples, including in males with abnormal semen analyses per the 2010 WHO guide. Apart from SDF levels, changes in sperm quality were not clinically significant in the second specimen and did not increase rates of ICSI. However, a second ejaculation after 3 h probably may reduce the necessity of costly and/or invasive ART strategies.  相似文献   
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