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61.
Urban Ecosystems - Latin America and the Caribbean (LAC) is one of the most urbanized and biologically diverse regions in the world but is often characterized by weak environmental governance and...  相似文献   
62.
Objective: To describe sexual practices in Mexican lesbian and bisexual women. Materials and method: An online survey was conducted with a nonprobabilistic sample of self-identified lesbian (n?=?768) and bisexual (n?=?371) women from the 32 states of Mexico. Results: Lesbians less frequently reported having had sex with a man than bisexual women. Preferred sexual practices with other women were external genital stimulation with fingers, internal genital stimulation with fingers, and oral genital stimulation. Most (~80%) participants did not use protection to prevent sexually transmitted infections. Conclusions: Our results can inform the design of promotion and prevention programs in sexual health aimed at sexual minority women.  相似文献   
63.
This paper develops a novel and efficient algorithm for Bayesian inference in inverse Gamma stochastic volatility models. It is shown that by conditioning on auxiliary variables, it is possible to sample all the volatilities jointly directly from their posterior conditional density, using simple and easy to draw from distributions. Furthermore, this paper develops a generalized inverse gamma process with more flexible tails in the distribution of volatilities, which still allows for simple and efficient calculations. Using several macroeconomic and financial datasets, it is shown that the inverse gamma and generalized inverse gamma processes can greatly outperform the commonly used log normal volatility processes with Student’s t errors or jumps in the mean equation.  相似文献   
64.
An accurate procedure is proposed to calculate approximate moments of progressive order statistics in the context of statistical inference for lifetime models. The study analyses the performance of power series expansion to approximate the moments for location and scale distributions with high precision and smaller deviations with respect to the exact values. A comparative analysis between exact and approximate methods is shown using some tables and figures. The different approximations are applied in two situations. First, we consider the problem of computing the large sample variance–covariance matrix of maximum likelihood estimators. We also use the approximations to obtain progressively censored sampling plans for log-normal distributed data. These problems illustrate that the presented procedure is highly useful to compute the moments with precision for numerous censoring patterns and, in many cases, is the only valid method because the exact calculation may not be applicable.  相似文献   
65.
Many central banks set inflation targets over the medium term and inflation projections are a key input for monetary policy decision making. In this paper, we present the procedures used by the Spanish Central Bank staff to project consumer price inflation. We also provide some illustrations of their policy uses, such as fan charts, deflation probabilities and the monitoring of inflation targets.  相似文献   
66.
In line with the orientation of EU economic policy, the Spanish government has favoured a strategy of internal devaluation as a way of adjusting price levels within the currency union. The results of empirical studies indicate that the internal devaluation applied in Spain does not seem to have attained the desired goals in terms of reducing the relative prices of exports and consolidating a model of growth based on external demand. Indeed, the estimates drawn up show that tailwinds – the depreciation of the euro and the fall in risk premium as results of the measures taken by the ECB, greater economic activity by trading partners and the fall in the price of oil – exercised a decisive influence in the trends followed by the prices of exports and the balance of trade during the period of crisis management in Spain.  相似文献   
67.
Nongovernmental organizations (NGOs) are established not with the aim of making profits but rather to provide social values by implementing different projects and activities. Transmitting complete information about these projects to society is a key element of transparency, as they operate within an atmosphere of public trust. Although there is a large body of literature on transparency in NGOs from a global perspective, very little research has been conducted on transparency within the area of projects and activities. This study takes a deeper look at this line and contributes to the literature on transparency in NGOs by proposing an index to measure the information transparency of the projects implemented by these organizations. The index captures three dimensions of the information about the projects (technical, financial, and scope) and makes it possible to: analyze the level of transparency of the portfolio of projects, detect the specific aspects that could be improved in each organization, and carry out comparisons among organizations.  相似文献   
68.
Urbanization causes species loss around the world, but its effects on phylogenetic diversity are poorly known in tropical forests. Using a patch-landscape approach in an urbanizing region of the Brazilian Atlantic Forest, we tested whether the increase in landscape urbanization reduces plant species density, phylogenetic richness and divergence, and increases the relatedness among co-occurring individuals and species. We assessed plant responses to urbanization in adult (diameter at breast height?>?10 cm) and sapling communities (2.5–10 cm diameter) separately, as saplings are proxies of the future flora. We sampled 2860 woody plants belonging to 155 species in nine circular landscapes with urbanization level varying from 0% to 45%, and estimated the relatedness among the species that have increased and decreased in relative abundance in more urbanized landscapes (winner and losers, respectively). As expected, species density and phylogenetic richness decreased with the increase in urbanization. These responses were consistent for adult and sapling communities, suggesting a persistent loss of species and lineages in more urbanized landscapes. Contrary to our expectations, phylogenetic divergence and structure did not respond to urbanization, indicating that the more urbanized landscapes still retain much evolutionary history. However, because the relatedness among winners was greater than among losers, it is likely that the phylogenetic divergence gradually reduces and the relatedness increases, resulting in impoverished forests with uncertain ability to provide ecosystem services such as carbon storage and pest control. This environmental cost should be taken into account to align urban sprawl with biodiversity conservation.  相似文献   
69.
McClung  Teegan  Ibáñez  Inés 《Urban Ecosystems》2018,21(1):147-155
Urban Ecosystems - The global trend of increasing urbanization is generating isolated patches of vegetation that could be strongly influenced by the surrounding landscape. Simultaneously, many of...  相似文献   
70.
Urban Ecosystems - Urban bird communities are homogenized across large spatial scales, suggesting that the urban environment acts as an environmental filter. We hypothesize that large scale...  相似文献   
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