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排序方式: 共有233条查询结果,搜索用时 31 毫秒
71.
Marise Barreiros Horta Tulaci Bhakti Pedro Fialho Cordeiro Sónia Maria Carvalho-Ribeiro Geraldo Wilson Fernandes Fernando Figueiredo Goulart 《Urban Ecosystems》2018,21(6):1097-1111
The scarcity of green areas in urban landscapes hinders connectivity among sites reducing the flux of organisms and seed dispersal. Ramphastos toco is an effective plant disperser in tropical landscapes, playing an important role in conserving plant connectivity. In this study we combined two methods of landscape connectivity analysis, in a way not yet explored, to assess the potential contribution of Ramphastos toco to enhancing connectivity among urban vegetation patches. We used spatial modeling techniques to evaluate least cost routes, or those that facilitate bird movement through green urban areas, in Belo Horizonte, a city in Southeast Brazil. We also assessed the relative importance of forest patches for conserving both bird and seed dispersal fluxes using the integral index of connectivity. The resulting least cost route of greater accessibility for the species included in its course an important forest patch under environmental licensing for the construction of a residential condominium. The number of green urban areas covered by forest, of highest habitat quality for the species, summed to 155 patches. Of this total only 5.2% were relevant for regional connectivity, while the four most important patches are targeted by the city’s expansion plans. Ramphastos toco is an effective connector for tropical green urban areas given its adaptability, wide range of movement and seed dispersal effectiveness. We emphasize the need for incorporating ecological knowledge and the prioritization of green areas into city planning, since current expansion projects jeopardize forest patches that are crucial to the functional connectivity of the urban landscape. 相似文献
72.
Antonio Tienza Jose E. Robles Mateo Hevia Ruben Algarra Fernando Diez-Caballero Juan I. Pascual 《The aging male》2018,21(1):24-30
Aims: To assess prevalence of urinary incontinence (UI) after radical prostatectomy (RP) and to analyze which preoperative characteristics of the patients have influence on UI.Methods: Between 2002 and 2012, 746 consecutive patients underwent RP for clinically localized prostate cancer. We defined UI according to International Continence Society (ICS) definition: “the complaint of any involuntary leakage of urine” after 12?months of recovery, international consultation on incontinence questionnaire (ICIQ-SF) and pads/day was collected too. Clinical features and magnetic resonance imaging measurements were assessed. A multivariable logistic regression model predicting incontinence were built-in after adjust by cofounding factors and bootstrapping.Results: About 172 (23%) of the patients were classified as incontinent according to the ICS definition. The mean value of the ICIQ-SF was 10.87 (±4). 17.8% of patients use at least one pad/day, 11.9% use more than one pad/day. The preoperative factors independently influential in UI are: age [OR: 1.055; CI 95% (1.006–1.107), p?=?.028], urethral wall thickness [OR: 5.03; CI 95% (1.11–22.8), p?=?.036], history of transurethral resection of the prostate [OR: 6.13; CI 95% (1.86–20.18), p?=?.003] and membranous urethral length [OR: 0.173; CI 95% (0.046–0.64), p?=?.009]. The predictive accuracy of the model is 78.7% and the area under the curve (AUC) value 71.7%.Conclusions: Urinary incontinence after radical prostatectomy has different prevalence depending on the definition. Age, prior transurethral resection of the prostate (TURP), membranous urethral length (MUL) and urethral wall thickness (UWT) were risk factors. 相似文献
73.
Susana Jiménez-Murcia Fernando Fernández-Aranda Gemma Mestre-Bach Roser Granero Salomé Tárrega Rafael Torrubia Neus Aymamí Mónica Gómez-Peña Carles Soriano-Mas Trevor Steward Laura Moragas Marta Baño Amparo del Pino-Gutiérrez José M. Menchón 《Journal of gambling studies / co-sponsored by the National Council on Problem Gambling and Institute for the Study of Gambling and Commercial Gaming》2017,33(2):579-597
Most individuals will gamble during their lifetime, yet only a select few will develop gambling disorder. Gray’s Reinforcement Sensitivity Theory holds promise for providing insight into gambling disorder etiology and symptomatology as it ascertains that neurobiological differences in reward and punishment sensitivity play a crucial role in determining an individual’s affect and motives. The aim of the study was to assess a mediational pathway, which included patients’ sex, personality traits, reward and punishment sensitivity, and gambling-severity variables. The Sensitivity to Punishment and Sensitivity to Reward Questionnaire, the South Oaks Gambling Screen, the Symptom Checklist-Revised, and the Temperament and Character Inventory-Revised were administered to a sample of gambling disorder outpatients (N = 831), diagnosed according to DSM-5 criteria, attending a specialized outpatient unit. Sociodemographic variables were also recorded. A structural equation model found that both reward and punishment sensitivity were positively and directly associated with increased gambling severity, sociodemographic variables, and certain personality traits while also revealing a complex mediational role for these dimensions. To this end, our findings suggest that the Sensitivity to Punishment and Sensitivity to Reward Questionnaire could be a useful tool for gaining a better understanding of different gambling disorder phenotypes and developing tailored interventions. 相似文献
74.
Julie L. Hotchkiss Robert E. Moore Fernando Rios-Avila Melissa R. Trussell 《Review of Economics of the Household》2017,15(3):707-737
The purpose of this paper is to assess the impact of economic changes in the 1990s and 2000s on the welfare of married households, taking into account the relative earnings structure of husband and wife. Modeling the household members’ joint labor supply, we find that families in which the wife is the higher wage earner experienced as much welfare gain in the 1990s and significantly higher welfare gains in the 2000s as families in which the husband is the higher wage earner. 相似文献
75.
76.
Determinants of infant and child mortality in Kenya: an analysis controlling for frailty effects 总被引:1,自引:0,他引:1
D. Walter Rasugu Omariba Roderic Beaujot Fernando Rajulton 《Population research and policy review》2007,26(3):299-321
In this paper, Weibull unobserved heterogeneity (frailty) survival models are utilized to analyze the determinants of infant
and child mortality in Kenya. The results of these models are compared to those of standard Weibull survival models. The study
particularly examines the extent to which child survival risks continue to vary net of observed factors and the extent to
which nonfrailty models are biased due to the violation of the statistical assumption of independence. The data came from
the 1998 Kenya Demographic and Health Survey. The results of the standard Weibull survival models clearly show that biodemographic
factors are more important in explaining infant mortality, while socioeconomic, sociocultural and hygienic factors are more
important in explaining child mortality. Frailty effects are substantial and highly significant both in infancy and in childhood,
but the conclusions remain the same as in the nonfrailty models. 相似文献
77.
We consider the problem of determining sharp upper bounds on the expected values of non-extreme order statistics based on i.i.d. random variables taking on N values at most. We show that the bound problem is equivalent to the problem of establishing the best approximation of the projection of the density function of the respective order statistic based on the standard uniform i.i.d. sample onto the family of non-decreasing functions by arbitrary N -valued functions in the norm of L2(0,1) space. We also present an algorithm converging to the local minima of the approximation problems. 相似文献
78.
Fernando DF 《Population studies》1972,26(3):445-453
Abstract The crude birth rate for Ceylon has been falling steadily between 1960 and 1970, except for a slight interruption in 1968. The fall between 1953 and 1963 has been documented elsewhere and this paper will therefore deal with the period 1963-69. 相似文献
79.
A parallel multi-population genetic algorithm for a constrained two-dimensional orthogonal packing problem 总被引:2,自引:2,他引:0
José Fernando Gonçalves Mauricio G. C. Resende 《Journal of Combinatorial Optimization》2011,22(2):180-201
This paper addresses a constrained two-dimensional (2D), non-guillotine restricted, packing problem, where a fixed set of
small rectangles has to be placed into a larger stock rectangle so as to maximize the value of the rectangles packed. The
algorithm we propose hybridizes a novel placement procedure with a genetic algorithm based on random keys. We propose also
a new fitness function to drive the optimization. The approach is tested on a set of instances taken from the literature and
compared with other approaches. The experimental results validate the quality of the solutions and the effectiveness of the
proposed algorithm. 相似文献
80.