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关键词： Crystallographic sphere packing   Hyperbolic reflection groups   Arithmetic groups   Coxeter diagram   Vinberg's algorithm  

摘要： This paper seeks to catalogue and examine crystallographic sphere packings as defined by Kontorovich and Nakamura. There exist at least three sources which give rise to crystallographic packings, namely polyhedra, reflective extended Bianchi groups, and various higher dimensional quadratic forms. When applied in conjunction with the Koebe-Andreev-Thurston Theorem, Kontorovich and Nakamura's Structure Theorem guarantees crystallographic packings to be generated from polyhedra in n = 2. The Structure Theorem similarly allows us to generate packings from the reflective extended Bianchi groups in n = 2 by applying Vinberg's algorithm to obtain the appropriate Coxeter diagrams. In n > 2, the Structure Theorem when used with Vinberg's algorithm allows us to explore whether certain Coxeter diagrams in Hn+1 for a given quadratic form admit a packing at all. Kontorovich and Nakamura's Finiteness Theorem shows that there exist only finitely many classes of superintegral such packings, all of which exist in dimensions n <= 20. In this work, we systematically determine all known examples of crystallographic sphere packings. (C) 2019 Elsevier Inc. All rights reserved.

关键词： sparse representation   information entropy   pseudo-labeling   intrinsic image decomposition   hyperspectral image classification   FEATURE-EXTRACTION   DECOMPOSITION   OPTIMIZATION   LEVEL  

摘要： Hyperspectral image classification methods may not achieve good performance when a limited number of training samples are provided. However, labeling sufficient samples of hyperspectral images to achieve adequate training is quite expensive and difficult. In this paper, we propose a novel sample pseudo-labeling method based on sparse representation (SRSPL) for hyperspectral image classification, in which sparse representation is used to select the purest samples to extend the training set. The proposed method consists of the following three steps. First, intrinsic image decomposition is used to obtain the reflectance components of hyperspectral images. Second, hyperspectral pixels are sparsely represented using an overcomplete dictionary composed of all training samples. Finally, information entropy is defined for the vectorized sparse representation, and then the pixels with low information entropy are selected as pseudo-labeled samples to augment the training set. The quality of the generated pseudo-labeled samples is evaluated based on classification accuracy, i.e., overall accuracy, average accuracy, and Kappa coefficient. Experimental results on four real hyperspectral data sets demonstrate excellent classification performance using the new added pseudo-labeled samples, which indicates that the generated samples are of high confidence.

关键词： Intensive interaction   staff   training   evaluation   adults   profound multiple learning disability   SERVICES   MODEL  

摘要： Purpose: Intensive interaction is used to increase communication in people at a pre-verbal stage of communication development. The aim of the study was to evaluate a city-wide implementation of intensive interaction training to care staff by investigating how staff use intensive interaction with adults with profound and multiple learning disability, and their perceived impact of intensive interaction on these service users. Method: In phase 1, a survey investigated the outcomes of intensive interaction training on the work practices of staff supporting people with profound and multiple learning disability. In phase 2, individual interviews were conducted with staff to further investigate these experiences and perceptions. Interviews were analyzed using thematic analysis. Results: Almost all of the participants (96%) reported using intensive interaction at work with 76% wanting to use intensive interaction with more people. Factors preventing staff from using Intensive Interaction were highlighted. Three over-arching themes were identified from the interviews; the impact of Intensive Interaction; facilitating the implementation of Intensive Interaction and; the organizational support and barriers to the implementation of Intensive Interaction. Conclusions: Training in intensive interaction at a city-wide level enables staff to develop their knowledge of the approach and to engage in intensive interaction to promote the social inclusion of adults with profound and multiple learning disability. The barriers preventing staff from engaging in Intensive Interaction with adults with profound and multiple learning disability should be addressed.

关键词： Agroecology   social capital   smallholder agriculture   Malawi   sub-Saharan Africa   SELF-RATED HEALTH   COLLECTIVE ACTION   FOOD SOVEREIGNTY   DECISION-MAKING   AGRICULTURE   MALAWI   NETWORKS   ADOPTION   MANAGEMENT   INNOVATION  

摘要： The pivotal role of social capital in smallholder agriculture is widely acknowledged. The growth effect of social capital manifests in how networks and trust facilitate access to productive resources and knowledge sharing among farmers. While sub-Saharan Africa is considered a storehouse of rich social capital, recent literature indicates its rapid depletion due mainly to the rise of capitalist agriculture and concomitant reorganization of the relations of production that characterize smallholder agriculture. Agroecology is an alternative approach to agriculture aimed at addressing the adverse impacts of capitalist agriculture, including improving farmer-to-farmer networks. In this paper, we draw on longitudinal data from a five-year participatory agroecology intervention in Malawi using Difference-in-Difference (DID) to compare the social capital endowment of agroecology-practicing households (n = 514) and a control group of non-agroecology households (n = 400). We further employed linear regression to examine the relationship between social capital and agroecology adoption. Results from the DID analysis show a positive and statistically significant change in mean social capital for participatory agroecology households (beta = 0.325, p< 0.001) compared to non-agroecology households (beta = 0.108) after accounting for theoretically relevant factors. Overall, the average treatment effect of the intervention on social capital was positive (beta = 0.217, p< 0.01). We also found a bidirectional relationship between social capital and adoption of agroecology practices (beta = 0.12, p< 0.001). These findings reveal the positive inroads of agroecology beyond the farm-level and demonstrate the potential for policymakers to leverage these benefits to promote sustainable agriculture.

摘要： IBI is the time in milliseconds between heartbeats, with lower IBI indicating faster heart rate. The typical male and female partners showed IBI cycling across all discussions. Cycling was weaker for females during support (vs. control) discussions but was stronger for males during support discussions. [Extracted from the article]

关键词： 质量控制   临床免疫检验   变异指数  

摘要： 目的:分析质量控制在临床免疫检验中的作用.方法:将2018年1月至2019年7月在本院实施免疫检验的78例患者视为研究对象,以电脑随机编号法划入常规组与质控组(n=39).常规组实施常规检测,质控组在此基础上实施免疫检验分析质量控制干预,比较患者的免疫检验平均变异指数及患者检验期间的工作满意率.结果:质控组患者的CEA、AFP、CA125及CA199变异指数均低于常规组患者,两组数据比较有统计学意义(P<0.05).常规组患者对检验工作实施的满意率为79.49%,质控组患者对检验工作实施的满意率为97.44%,质控组患者的满意率更高(P<0.05).结论:质量控制在临床免疫检验中的使用,能够降低免疫检验中各类指标的变异指数,提升患者的免疫检验工作满意率.