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31.
Stanislas Talaga Olivier Dézerald Alexis Carteron Céline Leroy Jean-François Carrias Régis Céréghino Alain Dejean 《Urban Ecosystems》2017,20(5):1001-1009
Due to habitat fragmentation, resource disruption and pollution, urbanization is one of the most destructive forms of anthropization affecting ecosystems worldwide. Generally, human-mediated perturbations dramatically alter species diversity in urban sites compared to the surroundings, thus influencing the functioning of the entire ecosystem. We investigated the taxonomic and functional diversity patterns of the aquatic macroinvertebrate communities in tank bromeliads by comparing those found in a small Neotropical city with those from an adjacent rural site. Changes in the quality of detrital inputs in relation to lower tree diversity and the presence of synanthropic species are likely important driving forces behind the observed structural changes in the urban site. Leaf-litter processors (i.e., shredders, scrapers) were positively affected in the urban site, while filter-feeders that process smaller particles produced by the activity of the shredders were negatively affected. Because we cannot ascertain whether the decline in filter-feeders is related to food web-mediated effects or to competitive exclusion (Aedes aegypti mosquitoes were present in urban bromeliads only), further studies are necessary to account for the effects of intra-guild competition or inter-guild facilitation. 相似文献
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Jean‐François Coeurjolly Jesper Møller Rasmus Waagepetersen 《Scandinavian Journal of Statistics》2017,44(1):192-203
This paper establishes a remarkable result regarding Palm distributions for a log Gaussian Cox process: the reduced Palm distribution for a log Gaussian Cox process is itself a log Gaussian Cox process that only differs from the original log Gaussian Cox process in the intensity function. This new result is used to study functional summaries for log Gaussian Cox processes. 相似文献
34.
The ordinary-G class of distributions is defined to have the cumulative distribution function (cdf) as the value of the cdf of the ordinary distribution F whose range is the unit interval at G, that is, F(G), and it generalizes the ordinary distribution. In this work, we consider the standard two-sided power distribution to define other classes like the beta-G and the Kumaraswamy-G classes. We extend the idea of two-sidedness to other ordinary distributions like normal. After studying the basic properties of the new class in general setting, we consider the two-sided generalized normal distribution with maximum likelihood estimation procedure. 相似文献
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Soner Coban Omer Gokhan Doluoglu Ibrahim Keles Hakan Demirci Ali Riza Turkoglu Muhammet Guzelsoy 《The aging male》2016,19(2):124-127
Objectives: To investigate the predictive values of free prostate-specific antigen (fPSA), total PSA (tPSA) and age on the prostate volume.Methods: The data of 2148 patients with lower urinary tract symptoms were analyzed retrospectively. The patients who had transrectal ultrasonography guided 10 core biopsies owing to the findings obtained on digital rectal examination and presence of high PSA levels (PSA?=?2.5–10?ng/dl), and proven to have BPH histopathologically were included in the study. Age, tPSA, fPSA and the prostate volumes (PV) of the patients were noted.Results: One thousand patients that fulfilled the inclusion criteria were included in the study. The PV of the patients were significantly correlated with age, tPSA and fPSA (p?0.001 and r?=?0.307, p?0.001 and r?=?0.382, p?0.001 and r?=?0.296, respectively). On linear regression model, fPSA was found as a stronger predictive for PV (AUC?=?0.75, p?0.001) when compared to age (AUC?=?0.64, p?0.001), and tPSA (AUC?=?0.69, p?=?0.013).Conclusions: Although tPSA is an important prognostic factor for predicting PV, the predictive value of fPSA is higher. PV can easily be predicted by using age, and serum tPSA and fPSA levels. 相似文献
37.
Sandra Nakić Radoš Hrvojka Soljačić Vraneš Marijana Šunjić 《Journal of sex research》2014,51(5):532-541
This cross-sectional study examined the role of maternal body image and body image self-consciousness in sexual satisfaction and intercourse frequency during pregnancy when controlling for satisfaction with partnership. Pregnant women in their third trimester of pregnancy (N = 150) participated in the study. Body image was measured by the Body Areas Satisfaction Scale (BASS) and Body Image Self-Consciousness Scale (BISC), while relationship satisfaction was measured by different subscales of the Perceived Quality of Marital Relationship (PQMR) Scale. Sexual satisfaction was also measured by one of the subscales of the PQMR (Intimate Relationship). The sexual behavior questionnaire comprised questions about frequency of sexual intercourse, desire, and other aspects of sexual functioning as well as the reasons that might prevent women from having intercourse during pregnancy. Findings suggested that satisfaction with body image and body image self-consciousness were related to sexual satisfaction. Nevertheless, other aspects of partnership, such as communication, appeared to be much more important predictors of sexual satisfaction than body image variables. The best predictor of sexual frequency was fear that intercourse might harm the fetus. Implications for education about sexuality issues in pregnancy are discussed. 相似文献
38.
If voters vote strategically, is it useful to offer them the possibility of expressing nuanced opinions, or would they always overstate the intensity of their preferences? For additive voting rules, say that a ballot is extremal if it is neither abstention-like nor can be expressed as a mixture of the available ballots. We give a sufficient condition for strategic equivalence: if two rules share the same set of extremal ballots (up to an homothetic transformation), they are strategically equivalent in large elections. This condition is also necessary for the strategic equivalence of positional rules. These results do not hold for small electorates. 相似文献
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Çi?dem Berber ÇelikHatice Odac? 《Children and youth services review》2012,34(1):200-204