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1.
Supplementation with anthocyanins, which are a type of flavonoids mainly found in various berries, is hypothesized to be a promising approach to lower the risk of developing cognitive decline. The aim of this systematic review was to provide a comprehensive overview of dietary intervention trials describing effects of berry anthocyanins on cognitive performance in humans, while also addressing potential underlying mechanisms. A total of 1197 articles were identified through a systematic search, and 49 studies reporting effects on cognitive performance (n = 18), vascular function (n = 22), or cardiometabolic risk markers (n = 32) were included. Significant improvements were observed on memory, while some of the studies also reported effects on attention and psychomotor speed or executive function. Vascular function markers such as brachial artery flow-mediated vasodilation were also affected and consistent evidence was provided for the beneficial effects of berry anthocyanins on endothelial function. Finally, studies reported improvements in blood pressure, but effects on metabolic risk markers (e.g. carbohydrate and lipid metabolism) were less consistent. In conclusion, this review provides evidence for the beneficial effects of berry anthocyanins on cognitive performance as memory improved. Whether observed anthocyanin-induced improvements in vascular function and blood pressure underlie beneficial effects on cognitive performance warrants further study.  相似文献   
2.
This paper presents a Danish study of mitigation directed at nature protection in environmental impact assessment (EIA) of infrastructure projects. The study is based on a document analysis of EIA reports, a workshop held with EIA professionals, and a study of two cases. The paper takes a point of departure in the mitigation hierarchy as a central conceptual framework, identifies which mitigation measures have been suggested in the EIA reports, and compares this to the mitigation hierarchy. Further, the paper explores the dynamics behind which mitigation measures are chosen and later implemented. The findings point to a discrepancy between the prevention principle embedded in the mitigation hierarchy and the actual EIA practice with increased use of nature compensation. Further, the research reveals significant variation in the design of mitigation measures, e.g. in the level of detail used in describing them and the level of clarity as to aims and actions.  相似文献   
3.
Selective mobility into and out of urban neighbourhoods is one of the main driving forces of segregation. Earlier research has found group differences in who wants to leave or who leaves certain types of neighbourhoods. A factor that has received little attention so far is that some residents will have a desire to leave their neighbourhood, but are unable to do so. If there are differences between population groups in the realisation of desires to leave the neighbourhood, this might lead to involuntary segregation. This paper uses a unique combination of register data and survey data. We combine data from a large housing survey in the Netherlands (WoON) with longitudinal register data from the Netherlands (SSD) which contains individual-level information on residential mobility histories. This allows us to study whether households with a desire to leave their neighbourhood do realise this desire and which households are successful in leaving which neighbourhoods. A more thorough insight in who wants to leave which neighbourhoods but is unable to do so will contribute to a better understanding of selective mobility and segregation. We find that ethnic minorities and low-income households are less likely to realise a desire to leave their neighbourhood. We expected that ethnic minorities would be especially unsuccessful in realising desires to leave minority concentration neighbourhoods; however, for none of the ethnic groups we found an effect of neighbourhood ethnic composition on the realisation of desires to leave.  相似文献   
4.
While biofuels have currently been regarded as a good alternative for fossil fuels, there remain many debates on their impacts on human and environment. This paper tried to shed light on bio-ethanol in Brazil as one of the main producers and exporters in the world. The main question was to understand “how sustainable is bio-ethanol production in Brazil?” To answer, the political motives of producing bio-ethanol followed by its ecological and socio-economic impacts were discussed. The paper concluded that although bio-ethanol production in Brazil seems environmentally friendly, it might socio-economically be hazardous.  相似文献   
5.
This article shows how large-scale commercial farmers, individually and collectively, are responding to land and water reform processes in the Thukela River basin, KwaZulu-Natal, South Africa. With a high degree of innovative agency, commercial farmers have effectively executed four strategies, enabling them to adapt and use their access to resources to neutralize multiple water reform efforts that once promised to be catalysts for inclusive change in the post-apartheid era. It is likely that policy alone will not facilitate the envisioned transformation, if local practices are not sufficiently understood and anticipated by the governmental officials charged with the implementation of water reform processes.  相似文献   
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Strategies for selecting informative data points for training prediction algorithms are important, particularly when data points are difficult and costly to obtain. A Query by Committee (QBC) training strategy for selecting new data points uses the disagreement between a committee of different algorithms to suggest new data points, which most rationally complement existing data, that is, they are the most informative data points. In order to evaluate this QBC approach on a real-world problem, we compared strategies for selecting new data points. We trained neural network algorithms to obtain methods to predict the binding affinity of peptides binding to the MHC class I molecule, HLA-A2. We show that the QBC strategy leads to a higher performance than a baseline strategy where new data points are selected at random from a pool of available data. Most peptides bind HLA-A2 with a low affinity, and as expected using a strategy of selecting peptides that are predicted to have high binding affinities also lead to more accurate predictors than the base line strategy. The QBC value is shown to correlate with the measured binding affinity. This demonstrates that the different predictors can easily learn if a peptide will fail to bind, but often conflict in predicting if a peptide binds. Using a carefully constructed computational setup, we demonstrate that selecting peptides with a high QBC performs better than low QBC peptides independently from binding affinity. When predictors are trained on a very limited set of data they cannot be expected to disagree in a meaningful way and we find a data limit below which the QBC strategy fails. Finally, it should be noted that data selection strategies similar to those used here might be of use in other settings in which generation of more data is a costly process.  相似文献   
8.
Cross-validation (CV) is a very popular technique for model selection and model validation. The general procedure of leave-one-out CV (LOO-CV) is to exclude one observation from the data set, to construct the fit of the remaining observations and to evaluate that fit on the item that was left out. In classical procedures such as least-squares regression or kernel density estimation, easy formulas can be derived to compute this CV fit or the residuals of the removed observations. However, when high-breakdown resampling algorithms are used, it is no longer possible to derive such closed-form expressions. High-breakdown methods are developed to obtain estimates that can withstand the effects of outlying observations. Fast algorithms are presented for LOO-CV when using a high-breakdown method based on resampling, in the context of robust covariance estimation by means of the MCD estimator and robust principal component analysis. A robust PRESS curve is introduced as an exploratory tool to select the number of principal components. Simulation results and applications on real data show the accuracy and the gain in computation time of these fast CV algorithms.  相似文献   
9.
Defining is a natural and necessary response to an ambiguous world, but causes fixation of categories and perspectives. On the basis of two earlier studies of project groups, we came to argue that redefining, and hence constructing various ways in which one perceives and understands something, enables groups to overcome imprisonment in meaning, establishing continuous development and flexibility. In this article, we first build a rationale for facilitating a process of redefining, to be taken into account when designing technology. Departing from this rationale, we discuss features of groupware technology that permit change by being flexible, and evoke redefining by engaging the user more actively. In so doing, we argue to think along new lines in the design of communication and collaboration technology. This paper proposes a specific perspective on technology, facilitating groups to engage in a productive, creative fashion of exploiting meaning potential.  相似文献   
10.
Six patients were examined by CT following head trauma, with bleeding from the ear and trismus. The mandibular condyles were normal and MRI in two patients demonstrated a normally located meniscus. An unilateral comminuted temporal bone fracture (TBF) with multiple fracture lines and one or more fragments detached from the petrous bone was demonstrated by CT in every patient. On physical examination there was trismus, inability to chew and local pain in the temporomandibular joint (TMJ) without tenderness and swelling. Measurements of vertical and horizontal mandibular movement unequivocally demonstrated TMJ malfunction in comparison with 10 controls. The malfunction was presumably due to instability of the fractured petrous bone, base of the TMJ. Immobilising one TMJ results in blocking of both joints. Clinical improvement in 6-8 months and absence of symptoms of joint derangement on repeated physical examination were thought to be explained by restored petrous bone stability following healing of the fractures. The phenomenon of trismus following TBF with normal TMJ is rare and not yet reported.  相似文献   
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