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81.
82.
Landscape fragmentation threatens habitats, biodiversity and other ecosystem services. In tackling this threat, the dynamic processes of social-ecological systems should be recognised and understood. Although network analysis based on graph theory has been recognised as an efficient way of spatially understanding landscape or habitat connectivity, only few studies have offered specific approaches or suggestions for integrating detailed social-ecological values into geographical distributions. As a contribution to bridging this gap, this paper introduces a social-ecological network model for the issue of landscape or habitat fragmentation applied to the case of Stockholm, Sweden. Graph theory was used in combination with sociotope and biotope maps for simple visualisation of network situations in two-dimensional maps. The European crested tit (Lophophanes cristatus), European common toad (Bufo bufo) and human beings were selected as indicator species, based on a landscape ecology analysis in Stockholm Municipality in 2009. Slope, land use and human disturbance maps were assessed in order to decide cost values of travelling from node to node. Lease-cost-path accumulation was used to create ideal reference maps of green networks. Three separate maps were then developed for suggesting efficient routes for three indicators in city scale that mainly connect from the Royal National City Park to the other parts of the city. The model in Hjorthagen neighbourhood to highlight two practical paths that link this fragmented community to its neighbouring park areas. Findings make it possible to address two scales of network improvement strategies, namely first for the city-scale green network that connects geographical habitats (nodes) and the regional green wedges of the city, and the second that of neighbourhood links between habitats in detailed layers of green networks. Strategic improvement potentials are presented based on ideal reference maps of green networks correspondingly.  相似文献   
83.
Impact mitigation practices are currently one of the hottest topics in conservation and regarded as priorities worldwide. Forest bat populations are known to provide important ecosystem services such as pest control and bat boxes have become one of the most popular management options for counteracting the loss of roosts. However, bat boxes tend to be employed in non-native forests near highly humanized areas where human disturbance is higher. The aim of this study was to evaluate how the surrounding landscape composition affects bat box occupancy in urban non-native forests along the Mediterranean corridor in the Northeastern Iberian Peninsula. Two hundred wooden bat boxes were monitored in young non-native forests in the period 2004–2012. The influence of land cover on occupancy rate of bat boxes was analysed at the landscape level in a 5 km buffer around bat-box stations. In total, 1659 inspections were carried out, in which a 15 % occupancy rate was detected. Bat boxes hosted three different species (Pipistrellus pygmaeus, Pipistrellus kuhlii and Nyctalus leisleri). More than 70 % of the occupancy can be explained by habitat and spatial composition. The presence of urban areas around bat boxes tends to have a negative impact on bat occupation rates; by contrast, forest coverage has a positive effect, especially for the tree-dwelling bats. These patterns could be associated with the large number of available roosts in buildings, microhabitat or phylopatry. Thus, to increase success, we suggest that landscape composition should be considered when using bat boxes for conservation.  相似文献   
84.
In this article, I focus on the management of postcolonial difference and the production of belonging in a white settler nation-state in order to rethink the notion of co-optation. I first develop a theoretical framework for understanding co-optation by separating the “who” and the “what” of co-optation: actors who embody diversity in public, political debate become the “who” of co-optation, as their agency is shaped by gendered and racialized processes of subject making. The “what” of co-optation revolves around particular conceptualizations of practices, rights and freedoms, associated in this case with “gender equality,” which is rendered an empty signifier in the process. I then illustrate this framework by drawing from research on the Sharia-based arbitration debate that took place in Ontario, Canada, between late 2003 and early 2006. I focus on the claims of two Canadian Muslim women activists to show that co-optation occurs as attempts to further liberation instead advance illiberal practices.  相似文献   
85.
This study investigated the development of the pointing–vocal coupling system. We were interested in the infants’ behavior to attune prosody with pointing intentions. Twenty‐five children were involved at 12, 15, and 18 months of age in an experimental procedure devised to elicit imperative and declarative pointing. Pointing, vocality associated with pointing, and the prosody of that vocality were analyzed. A significant increase in the coupling of pointing and vocality was observed from 12 to 15 months, and in the ability to differentiate prosody with respect to the intention of the gesture from 15 to 18 months. Also, the infants who pointed declaratively at 12 months were likely to couple declarative pointing with vocality at 15 months, and the infants who coupled at 15 months were likely to differentiate prosody by the pointing intention at 18 months. Results suggest that the match between prosody and pointing intentions emerges gradually during the first half of the second year of life. They also show a relationship between earlier and later pointing–vocal coupling, and a role for declarative communication in promoting that progression. Overall, our study supports the view of intentional communication as a time‐based and context‐based developmental process.  相似文献   
86.

Background

Centenarians are a growing population in Europe and present significant variability in motor and cognitive functions. The aim of our study was to characterize health status, as well as cognitive and motor functions in a group of Portuguese centenarians. In addition, our study also aimed at analyzing the relationship between cognitive functions and the burden of diseases affecting the elderly.

Methods

Fifty-two centenarians were evaluated using the Mini-Mental State Examination, short version. Walking-related parameters (velocity and time spent in the 3 m walk test), grip strength and number of age-related illnesses were also measured. The relationship between cognitive scores and time spent in the three metre walk test, velocity, grip strength and number of diseases was analysed.

Results

Cognitive scores showed a positive correlation with both handgrip strength and time spent in the three metre walk. In contrast, no association was found between cognitive scores and the presence/absence of disease, walking velocity or number of diseases present.

Conclusions

These results suggest that in centenarians, cognitive functions may be related with motor functions.
  相似文献   
87.
In this paper, we show that proportions of observations that fall into a random region determined by a given Borel set and a central order statistic converge almost surely, provided that the corresponding population quantile is unique. We also describe three types of possible asymptotic behaviour of these proportions in the case of non-unique population quantile. As an application of our findings we establish limiting properties of numbers of ties with a central order statistics in a discrete sample. Our results are derived not only for independent and identically distributed observations but more generally for strictly stationary and ergodic sequences of random variables.  相似文献   
88.
This research was motivated by our goal to design an efficient clinical trial to compare two doses of docosahexaenoic acid supplementation for reducing the rate of earliest preterm births (ePTB) and/or preterm births (PTB). Dichotomizing continuous gestational age (GA) data using a classic binomial distribution will result in a loss of information and reduced power. A distributional approach is an improved strategy to retain statistical power from the continuous distribution. However, appropriate distributions that fit the data properly, particularly in the tails, must be chosen, especially when the data are skewed. A recent study proposed a skew-normal method. We propose a three-component normal mixture model and introduce separate treatment effects at different components of GA. We evaluate operating characteristics of mixture model, beta-binomial model, and skew-normal model through simulation. We also apply these three methods to data from two completed clinical trials from the USA and Australia. Finite mixture models are shown to have favorable properties in PTB analysis but minimal benefit for ePTB analysis. Normal models on log-transformed data have the largest bias. Therefore we recommend finite mixture model for PTB study. Either finite mixture model or beta-binomial model is acceptable for ePTB study.  相似文献   
89.
In the article, properties of the Bennett test and Miller test are analyzed. Assuming that the sample size is the same for each sample and considering the null hypothesis that the coefficients of variation for k populations are equal against the hypothesis that k ? 1 coefficients of variation are the same but differ from the coefficient of variation for the kth population, the empirical significance level and the power of the test are studied. Moreover, the dependence of the test statistic and the power of the test on the ratio of coefficients of variation are considered. The analyses are performed on simulated data.  相似文献   
90.
Most literature on racial prejudice deals with the racial attitudes of the ethnic majority and ethnic minorities separately. This paper breaks this tradition. We examine the social distance attitudes of white and non‐white British residents to test if these attitudes follow the same trends over time, whether they are driven by the same social processes and whether they are inter‐related. We have three main findings. Firstly, social distance from other ethnic groups has declined over time for both white and ethnic minority Britons. For the white majority there are both period and cohort elements to this decline. Secondly, we see some evidence that social distance between the majority and minority groups is reciprocal. Specifically, minorities who experience rejection by the white British feel a greater sense of distance from them. Thirdly, we find that all groups share the perception of the same ethnic hierarchy. We see evidence of particularly widespread hostility towards Muslim Britons from all ethnic groups suggesting that Muslims are singled out for negative attention from many British residents of all other backgrounds, including a large number who do not express hostility to other groups.  相似文献   
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