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1.
In this paper, we consider a statistical estimation problem known as atomic deconvolution. Introduced in reliability, this model has a direct application when considering biological data produced by flow cytometers. From a statistical point of view, we aim at inferring the percentage of cells expressing the selected molecule and the probability distribution function associated with its fluorescence emission. We propose here an adaptive estimation procedure based on a previous deconvolution procedure introduced by Es, Gugushvili, and Spreij [(2008), ‘Deconvolution for an atomic distribution’, Electronic Journal of Statistics, 2, 265–297] and Gugushvili, Es, and Spreij [(2011), ‘Deconvolution for an atomic distribution: rates of convergence’, Journal of Nonparametric Statistics, 23, 1003–1029]. For both estimating the mixing parameter and the mixing density automatically, we use the Lepskii method based on the optimal choice of a bandwidth using a bias-variance decomposition. We then derive some convergence rates that are shown to be minimax optimal (up to some log terms) in Sobolev classes. Finally, we apply our algorithm on the simulated and real biological data.  相似文献   
2.
Segregation may have profound effects when it is paired with an accumulation of inequalities. This is namely the case when ethnic and socioeconomic segregation overlap. Few studies in Europe have, however, addressed the relationship between ethnic and socioeconomic segregation in a comprehensive manner. This paper first aims at investigating the interrelation between ethnic and socioeconomic segregation in Belgium. Second it looks into the role of scale in the relationship between ethnic and socioeconomic segregation. The analyses are based on the newly available geocoded data from the 2011 Belgian census. These data were used to construct individualised neighbourhoods at nine scales with a nearest-neighbours approach for the urban agglomerations of Brussels, Antwerp, and Liege. Ethnic and socioeconomic indicators calculated for these individualised neighbourhoods were then inputted in independent factor analyses for each agglomeration. The results reveal remarkably similar segregation patterns in the three cities. Our analyses give way for three main conclusions: there is an undeniable process of spatial isolation of deprived migrants in Belgium’s inner cities; despite the central location of neighbourhoods with high concentration of migrants and poverty, the scope of isolation is considerably high, both in extension and in population density; and macro/national factors such as housing policies and territorial processes seem to shape the segregation patterns in Belgian cities.  相似文献   
3.
What are the local characteristics influencing where new nonprofits will be established? How important are community needs, available resources, or the existence of similar organizations for nonprofits’ location? This paper analyzes how the characteristics of 5562 Brazilian municipalities in the year 2000 help explain the location of nonprofits formed between 2001 and 2010. Based on geographically weighted regressions, results indicate that neither access to resources nor poor socioeconomic indicators are powerful influences on nonprofit location in Brazilian municipalities. The main predictor of nonprofit entry is a high pre-existing density of nonprofits in that area. These findings, however, vary across regions and nonprofit fields of activity. By mapping the effect of key explanatory variables, this paper helps understand nonprofit location. The methodology and findings on nonprofit location presented here are novel and may contribute to research in other countries.  相似文献   
4.
Recent theorizations of affect have focused largely on Western historical, political and aesthetic contexts to distinguish between affect and emotion. Notably, these interventions offer new imaginaries to reinvigorate analysis of politics in the face of shrinking possibilities. However, much of this literature views affect as autonomous from emotion, while overlooking the political history of development and the differentiated relation to affect under colonial capitalism in other historical contexts. This paper studies subaltern engagement in activist performance in India to address these issues. It thinks through Lauren Berlant's account of the aesthetic genre and affective structure of cruel optimism, and her focus on historical contexts where people have recently lost the vision of a good life. By contrast, focusing on the historical present of those born into a pervasive and intractable sense of marginality and insecurity, I ask: what is the subject's relation to affect and activism in contexts where the loss of vision of a good life is not new under neoliberalism, but rather, reworks long-standing violence and inclusion/exclusion of colonial capitalism and nation-state histories. I argue that it is useful to understand Berlant's ‘materialist context for affect theory’ in light of uneven global histories of colonialism, development and neoliberalism. The affective experience of time is different across different spaces. As such, this paper contributes a global materialist context for affect theory, by focusing on activist theatre by a tribe called Chhara, designated ‘born criminals’ by British colonial law – a status legally denotified in 1952, but that is practically still effective in postcolonial India. Competing affective structures – sentimental optimism, cruel pessimism, betrayal and ordinary regard – shape and are shaped by Chhara negotiations with branded criminality. Ultimately, for the postcolonial subject, surviving in the neoliberal present involves vacillating among competing affective structures, only some of which generate sustained political critique.  相似文献   
5.
This paper explores the importance of researching the intuitiveness in the product use. It approaches the intuitiveness influence for users that already had a visual experience of the product. Finally, it is suggested the use of a table that relates the tasks performed while using a product, the features for an intuitive use and the performance metric "task success".  相似文献   
6.
The main objective of this study is to evaluate the impact of school furniture and work surface lighting on the body posture of two public Middle School students from Paraíba (Brazil). The target population included 8th grade groups involving 31 students. Brazilian standards for lighting levels, the CEBRACE standards for furniture measurements and the Postural Assessment Software (SAPO) for the postural misalignment assay were adopted for the measurements comparison. The statistic analysis includes analyses of parametric and non-parametric correlations. The results show that the students' most affected parts of the body were the spine, the regions of the knees and head and neck and about 90% of the students presented postural misalignment. The lighting levels were usually found below 300 lux, below recommended levels. Such results indicate the need of investments in more suitable school furniture and structural reforms aimed at improving the lighting in the classrooms, which could fulfill the students' profile and reduce their complaints.  相似文献   
7.
Clustered binary responses are often found in ecological studies. Data analysis may include modeling the marginal probability response. However, when the association is the main scientific focus, modeling the correlation structure between pairs of responses is the key part of the analysis. Second-order generalized estimating equations (GEE) are established in the literature. Some of them are more efficient in computational terms, especially facing large clusters. Alternating logistic regression (ALR) and orthogonalized residual (ORTH) GEE methods are presented and compared in this paper. Simulation results show a slightly superiority of ALR over ORTH. Marginal probabilities and odds ratios are also estimated and compared in a real ecological study involving a three-level hierarchical clustering. ALR and ORTH models are useful for modeling complex association structure with large cluster sizes.  相似文献   
8.
Due to the increase of production costs in manual harvesting, strategies must be developed in order to overcome these effects, such as the attempts in implementing agricultural machines in harvest activities, whether being totally or partially mechanized. This study brings a qualitative and quantitative comparison on the impacts in work conditions and productivity in Brazilian orchards caused by the use of semi-mechanized harvesting systems, such as multiplatforms. The results come from the application of Ergonomic Work Analysis method, which focuses in the activity, quantifying and analyzing times and frequencies of the harvesting cycle, as well as the amount of movements. To achieve this, footage, interviews and a stopwatch were used in the observation 12 pickers' work cycles, six for each method of harvesting. The data interpretation pointed to improvement in working conditions with a reduction in the amount of movements performed by the picker, and increase of up to 60% in productivity with the use of semi-mechanized harvesting. Thus, the found results indicate the viability of this harvesting method. However, other variables must be observed in future studies in order to complete the guidelines for a healthy progress in the area of citrus harvesting in Brazil.  相似文献   
9.
The study aimed to conduct a literature review as a step of the development of a new questionnaire about the nursing workers' perception of job factors that may lead to musculoskeletal symptoms. An information synthesis was achieved by collecting data from studies that fitted the search criteria. The results showed that despite the existence of several job factors related to musculoskeletal symptoms, no specific questionnaire that evaluates this relationship was found. Therefore, this literature review presents important topics for developing the first questionnaire to analyze work activities that may contribute to pain and discomfort among nursing personnel.  相似文献   
10.
The objective of meat inspection is to promote animal and public health by preventing, detecting, and controlling hazards originating from animals. With the improvements of sanitary level in pig herds, the hazards profile has shifted and the inspection procedures no longer target major foodborne pathogens (i.e., not risk based). Additionally, carcass manipulations performed when searching for macroscopic lesions can lead to cross‐contamination. We therefore developed a stochastic model to quantitatively describe cross‐contamination when consecutive carcasses are submitted to classic inspection procedures. The microbial hazard used to illustrate the model was Salmonella, the data set was obtained from Brazilian slaughterhouses, and some simplifying assumptions were made. The model predicted that due to cross‐contamination during inspection, the prevalence of contaminated carcass surfaces increased from 1.2% to 95.7%, whereas the mean contamination on contaminated surfaces decreased from 1 logCFU/cm² to ?0.87 logCFU/cm², and the standard deviations decreased from 0.65 to 0.19. These results are explained by the fact that, due to carcass manipulations with hands, knives, and hooks, including the cutting of contaminated lymph nodes, Salmonella is transferred to previously uncontaminated carcasses, but in small quantities. These small quantities can easily go undetected during sampling. Sensitivity analyses gave insight into the model performance and showed that the touching and cutting of lymph nodes during inspection can be an important source of carcass contamination. The model can serve as a tool to support discussions on the modernization of pig carcass inspection.  相似文献   
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