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11.
Alien squirrels may seriously threaten native species by means of interspecific competition. In our work, we analysed whether the distribution of alien Siberian chipmunks within the Sigurtà Garden urban park (north-eastern Italy) changed after the natural spread of native Eurasian red squirrels in a 20-year period. Distribution of both squirrels was estimated through a citizen-science approach, in the first 10-year after red squirrel arrival 1 (i.e. Decade 1: 1997–2006) and in the second 10-year interval (i.e. Decade 2: 2007–2017). We compared habitat use of both species and we assessed whether a vertical segregation occurred through a dissimilarity index. Woodlands were selected by both species in both decades. Red squirrels also selected tree lines in Decade 1. A vertical segregation was apparent in Decade 1, whereas in Decade 2 both squirrel species were observed on the lowest branches or on the ground, where they are fed by humans. This was also confirmed by the habitat niche-overlap index, which increased in Decade 2. The extent of occurrence of Sciurus vulgaris increased throughout the park, whereas those of Eutamias sibiricus decreased. Differently from what is usually observed with alien squirrels, the spread of the native species appears to be halting and reversing the expansion of the non-native one.  相似文献   
12.
Taking their cue from a seeming dissonance between the theory of commodification and exploitation of migrant care workers and the case study of the outsourced self proposed by Hochschild, the author speculates whether or not the family–caregiver relationship may be equal and inclusive. The argument is unraveled by posing another question en route: what specific ‘catalysts’ can trigger ‘high-intensity affective relationships’? Elster defines 'essentially byproduct' the result of a process lacking any direct and conscious link between outcome and intention, and requiring the relaxation of the control of reason in order to be fulfilled. The author mixes significant theoretical results coming both from the relational Palo Alto School and from history of families studies, concluding that an equal and inclusive relationship may be like an Elster’s ‘essentially byproduct’ of a market relationship , when a high-intensity affective relation acts as a ‘catalyst’. The frame suggested in this article seems consistent with recent constructionist reinterpretations of the idea of kinship, which take shape and evolve through ‘everyday experiences’. Kinship thus shifts towards a more complex undefined category, that of Karsten’s relatedness. Speaking of which, the author argues some logical reasons suggesting a generalized adoption of the term only with great care and caution.  相似文献   
13.
We aimed to investigate the predictive factor of erectile dysfunction (ED) in prostate cancer (PCa) patients who underwent low-dose permanent I125 seed implant brachytherapy and to investigate if ED could represent a patient’s reported outcome measures (PROMs) of efficacy of BT and indirectly associated with biochemical recurrence free survival (BRFS). From 2000 to 2012, 176 consecutive patients with low-risk PCa underwent BT. ED was evaluated with the International Index of Erectile Function (IIEF-5). Cox regression analysis was performed to assess significant predictors of mild-to-severe ED and BRFS after BT, including covariates. The 10-year actuarial rate of ED was 66%. Subjects with severe ED had higher values of D90 (183.0 versus 177.0; p?p?p?p?=?0.20), while D90?≤?180?Gy independently predicted BCR (HR: 4.65; [95%CI: 1.25–17.34]; p?125 implant, but it is not associated with better BRFS.  相似文献   
14.
In the Design for All Approach (DfA), an important phase of the design process consists in the individuation of the so-called "limit users", that are that particular group of people with the most "critical" features for the autonomous fruition of a system or a product. Generally, however, it is not easy to identify them in a complete and objective way. A clear and complete outline of design requirements with respect to the "normal" use of a service, product or environment, moreover, is of fundamental importance in inclusive design. In fact, we know how bad design, that doesn't take in account the true "strategies of use", may lead to situations of handicap, also serious, temporary or permanent, regardless if the user is a "disabled" person or not. In relation to this scenario, the paper shows the results of a research which has developed the "Ability/Difficulty Table" ("A/D Table"), a new tool useful to identify the so-called "limit users" and their needs with respect to different activities, linking the main "difficulties", expressed by people, with the "abilities" required to carry out in autonomy the investigated activity.  相似文献   
15.
A number of recent papers have focused on the problem of testing for a unit root in the case where the driving shocks may be unconditionally heteroskedastic. These papers have, however, taken the lag length in the unit root test regression to be a deterministic function of the sample size, rather than data-determined, the latter being standard empirical practice. We investigate the finite sample impact of unconditional heteroskedasticity on conventional data-dependent lag selection methods in augmented Dickey–Fuller type regressions and propose new lag selection criteria which allow for unconditional heteroskedasticity. Standard lag selection methods are shown to have a tendency to over-fit the lag order under heteroskedasticity, resulting in significant power losses in the (wild bootstrap implementation of the) augmented Dickey–Fuller tests under the alternative. The proposed new lag selection criteria are shown to avoid this problem yet deliver unit root tests with almost identical finite sample properties as the corresponding tests based on conventional lag selection when the shocks are homoskedastic.  相似文献   
16.
The aim of this paper is to analyze the internationalization of Italian firms in Romania, operating in the sectors of footwear, furniture and industrial refrigeration. After describing and quantifying the internationalization process between Veneto and Romania, we discuss for each of the sectors, the changes that occurred in the organisation of the production processes within the firms, and particularly how such processes have been fragmented. This article draws on numerous case studies, posits different models of value chain governance, and discusses their implications for regional development and sustainability.  相似文献   
17.
We present a new Immune Algorithm, IMMALG, that incorporates a Stochastic Aging operator and a simple local search procedure to improve the overall performances in tackling the chromatic number problem (CNP) instances. We characterize the algorithm and set its parameters in terms of Kullback Entropy. Experiments will show that the IA we propose is very competitive with the state-of-art evolutionary algorithms.  相似文献   
18.
Our study aims to assess the prevalence of behavioural addictions in an adolescent population, evaluating the effects of gender and age, and to assess the correlations among different behavioural addictions. 2853 high school students were assessed in order to evaluate the prevalence of behavioural addictions such as Pathological Gambling (PG), Compulsive Buying (CB), Exercise Addiction (EA), Internet Addiction (IA), and Work Addiction (WA), in a population of Italian adolescents. The South Oaks Gambling Screen-Revised Adolescent (SOGS-RA), the Compulsive Buying Scale (CBS), the Exercise Addiction Inventory (EAI), the Internet Addiction Test (IAT), and the Work Addiction Risk Test (WART), were compiled anonymously by the students. Overall prevalence was 7.0% for PG, 11.3% for CB, 1.2% for IA, 7.6% for WA, 8.5% for EA. PG and EA were more common among boys, while gender had no effect on the other conditions. CB was more common among younger (<18 years old) students. The scores of all of these scales were significantly correlated. The strong correlation among different addictive behaviours is in line with the hypothesis of a common psychopathological dimension underlying these phenomena. Further studies are needed to assess personality traits and other clinical disorders associated with these problems behaviours.  相似文献   
19.
Using two-wave panel data drawn from the Itagen2 Survey, we analyse the assimilation process of a sample of 11–13-year-old children of immigrants enrolled in Italian junior high schools, comparing them to children whose parents are both Italian. In seeking to adapt the traditional segmented assimilation theory to the Italian context, and using a dynamic and multidimensional approach, we consider four aspects: linguistic preferences, scholastic performance, friendship with peers, and sense of belonging in Italy. We synthesize a crude index of assimilation level, analyse its changes in a 2-year period and define its main determinants. The results demonstrate that generation status (place of birth of the children and of their parents, and length of stay) and the family’s socio-economic condition are closely related to assimilation level. These findings provide information useful for a better understanding of these children and their way of life.  相似文献   
20.
In this article, ambiguity attitude is measured through the maximum price a decision maker is willing to pay to know the probability of an event. Two problems are examined in which the decision maker faces an act: in one case, buying information implies playing a lottery, while, in the other case, buying information gives also the option to avoid playing the lottery. In both decision settings, relying on the Choquet expected utility model, we study how the decision maker??s risk and ambiguity attitudes affect the reservation price for ambiguity resolution. These effects are analyzed for different levels of ambiguity of the act. Operating instructions for the elicitation of the reservation price for ambiguity resolution in an experimental setting are provided at the end of the article.  相似文献   
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