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排序方式: 共有4100条查询结果,搜索用时 13 毫秒
1.
Louise Bezuidenhout 《Developing world bioethics》2019,19(1):18-24
Most scientists recognize the importance of sharing data online in an open fashion. Nonetheless, many studies have documented the concerns that accompany data sharing activities, including loss of credit or IP, misuse and the time needed to curate interoperable data. To this end, discussions around data sharing often identify incentives that could potentially ameliorate these disincentivising concerns. Nonetheless, current Open Data discussions often rely on evidence‐based studies to identify the disincentives to overcome. This results in highly specific and directed interventions. In contrast, this paper offers a different interpretation of these concerns. To do so, it makes use of the Thomas Theorem which suggests that: “If men define situations as real, they are real in their consequences”. Using empirical evidence from sub‐Saharan African (bio)chemistry laboratories, this paper illustrates how individual perceptions of research environments – whether associated with evidence or not – are highly influential in shaping data sharing practices. It concludes with the suggestion that discussion on incentivising data sharing amongst scientific communities need to take a broader set of concerns into account and offer a more creative approach to ameliorating environmental disincentives. 相似文献
2.
Nanna Brink Scholz Lars Bolund Mette Nyegaard Louise Faaborg Mette Warming J?rgensen Helle Lund Isa Niemann Lone Sunde 《PloS one》2015,10(11)
Hydatidiform moles (HMs) are abnormal human pregnancies with vesicular chorionic villi, imposing two clinical challenges; miscarriage and a risk of gestational trophoblastic neoplasia (GTN). The parental type of most HMs are either diandric diploid (PP) or diandric triploid (PPM). We consecutively collected 154 triploid or near-triploid samples from conceptuses with vesicular chorionic villi. We used analysis of DNA markers and/or methylation sensitive-MLPA and collected data from registries and patients records. We performed whole genome SNP analysis of one case of twinning (PP+PM).In all 154 triploids or near-triploids we found two different paternal contributions to the genome (P1P2M). The ratios between the sex chromosomal constitutions XXX, XXY, and XYY were 5.7: 6.9: 1.0. No cases of GTN were observed. Our results corroborate that all triploid human conceptuses with vesicular chorionic villi have the parental type P1P2M. The sex chromosomal ratios suggest approximately equal frequencies of meiosis I and meiosis II errors with selection against the XYY conceptuses or a combination of dispermy, non-disjunction in meiosis I and meiosis II and selection against XYY conceptuses. Although single cases of GTN after a triploid HM have been reported, the results of this study combined with data from previous prospective studies estimate the risk of GTN after a triploid mole to 0% (95% CI: 0–1,4%). 相似文献
3.
Extensive clearing of native vegetation on rural properties throughout Australia over the last century has generated significant damage to biodiversity. Conservation tenders have been broadly used to reduce the detrimental impact of such widespread clearance. To date, Australian conservation tender research has largely been limited to program evaluations and landholder surveys. This analysis differs by comparing and contrasting the views of non-landholders involved with these programs with those of participant landholders. The non-landholder group consists of individuals with involvement in conservation tenders across Australia. By contrast, the landholder group consists of individuals with participation experience in a series of Victorian tender initiatives. Each group is surveyed to investigate the drivers of cost-effectiveness within tender programs and landholder participation. This analysis explores these two perspectives, revealing important convergences and divergences in opinion. Both practitioners and landholders indicate that programs supported by close agency–landholder relationships and offering flexibility to landholders are most likely to succeed, particularly where landholders perceive the tender instrument to be fair. Whilst practitioners emphasise the role of transaction costs issues and program characteristics in achieving cost-effective biodiversity outcomes, landholders indicate that these factors are less important to participation rates. This research is important to guide future implementation of tender programs both in Australia and internationally. 相似文献
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David A. Cappel Louise Lantier Brian T. Palmisano David H. Wasserman John M. Stafford 《PloS one》2015,10(8)
Pharmacological approaches to reduce obesity have not resulted in dramatic reductions in the risk of coronary heart disease (CHD). Exercise, in contrast, reduces CHD risk even in the setting of obesity. Cholesteryl Ester Transfer Protein (CETP) is a lipid transfer protein that shuttles lipids between serum lipoproteins and tissues. There are sexual-dimorphisms in the effects of CETP in humans. Mice naturally lack CETP, but we previously reported that transgenic expression of CETP increases muscle glycolysis in fasting and protects against insulin resistance with high-fat diet (HFD) feeding in female but not male mice. Since glycolysis provides an important energy source for working muscle, we aimed to define if CETP expression protects against the decline in exercise capacity associated with obesity. We measured exercise capacity in female mice that were fed a chow diet and then switched to a HFD. There was no difference in exercise capacity between lean, chow-fed CETP female mice and their non-transgenic littermates. Female CETP transgenic mice were relatively protected against the decline in exercise capacity caused by obesity compared to WT. Despite gaining similar fat mass after 6 weeks of HFD-feeding, female CETP mice showed a nearly two-fold increase in run distance compared to WT. After an additional 6 weeks of HFD-feeding, mice were subjected to a final exercise bout and muscle mitochondria were isolated. We found that improved exercise capacity in CETP mice corresponded with increased muscle mitochondrial oxidative capacity, and increased expression of peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α). These results suggest that CETP can protect against the obesity-induced impairment in exercise capacity and may be a target to improve exercise capacity in the context of obesity. 相似文献
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Louise E. Anderson 《Biochemical and biophysical research communications》1981,99(4):1199-1202
Transaldolase is inactivated when intact pea leaf chloroplasts are irradiated. This light inactivation is 3-(3,4-dichlorophenyl)-1,1-dimethyl urea, arsenite and sulfite-sensitive, implicating the Light Effect Mediator system in light inactivation of this oxidative pentose phosphate pathway enzyme. 相似文献
10.
Shahin Zibaee Graham Fraser Ross Jakes David Owen Louise C. Serpell R. Anthony Crowther Michel Goedert 《The Journal of biological chemistry》2010,285(49):38555-38567
Filamentous inclusions made of α-synuclein are found in nerve cells and glial cells in a number of human neurodegenerative diseases, including Parkinson disease, dementia with Lewy bodies, and multiple system atrophy. The assembly and spreading of these inclusions are likely to play an important role in the etiology of common dementias and movement disorders. Both α-synuclein and the homologous β-synuclein are abundantly expressed in the central nervous system; however, β-synuclein is not present in the pathological inclusions. Previously, we observed a poor correlation between filament formation and the presence of residues 73–83 of α-synuclein, which are absent in β-synuclein. Instead, filament formation correlated with the mean β-sheet propensity, charge, and hydrophilicity of the protein (global physicochemical properties) and β-strand contiguity calculated by a simple algorithm of sliding averages (local physicochemical property). In the present study, we rendered β-synuclein fibrillogenic via one set of point mutations engineered to enhance global properties and a second set engineered to enhance predominantly β-strand contiguity. Our findings show that the intrinsic physicochemical properties of synucleins influence their fibrillogenic propensity via two distinct but overlapping modalities. The implications for filament formation and the pathogenesis of neurodegenerative diseases are discussed. 相似文献