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关键词： Spatial interaction   Land-use function complementarity   Gravity model   Smart card data  

摘要： Spatial interaction is an important phenomenon that reflects the human-land relationship and has long been a core topic in multiple fields, such as urban planning, transportation planning, commodity trade, and epidemic prevention. However, as an underlying cause of spatial interaction, function complementarity has been ignored by existing research for a long time. At the same time, the increase in Big Data of travel behavior provides an opportunity to model spatial interactions in detail. In this paper, we proposed three types of land-use function complementarity indices according to the spatiotemporal characteristics of human mobility. These complementarity indices are introduced to spatial interaction to improve the gravity model. We also examined the effects of land function complementarity on intra-urban spatial interaction using smart card records of metro system for different time periods and directions. The results showed that all models could be improved by introducing the land-use function complementarity indices, but the models with a single travel pattern and clear direction were explained more by the complementary indices. The indices we propose in this paper could be used for predicting spatial flow and trip distribution, and also could be considered as factors in researches about transportation and land-use planning.

关键词： Social anxiety   Positive affect   Negative affect   Social stress   Anxiety reactivity  

摘要： Background: Positive affect (PA) attenuates negative reactivity to stress;however, this adaptive function of PA is seldom studied in psychiatric conditions characterized by more extreme forms of affective responding. We tested distinct associations of PA and negative affect (NA) with anxiety reactivity in participants with social anxiety disorder (SAD)-a condition characterized by heightened NA and diminished PA-and non-SAD control subjects. Method: Adults with a principal diagnosis of SAD (n = 71) and those without a psychiatric history (n = 36) rated their PA and NA during the past week, and were exposed to a laboratory stressor wherein they delivered a video-recorded speech on a controversial topic. Anxiety reactivity was assessed in terms of anticipatory anxiety prior to the speech, and observer-rated anxiety-related behavior during the speech. Results: Across all participants, higher PA significantly predicted lower anticipatory anxiety and less anxiety-related behavior, beyond level of NA;lower NA significantly predicted attenuated anticipatory anxiety, but not anxiety-related behavior, beyond level of PA. The association between PA and stress reactivity was diminished for individuals with especially elevated NA, as well as for individuals with SAD compared to those without. Conclusions: PA may be protective against negative reactivity to social stress;however, theoretical models and clinical applications should consider possible interactive effects of PA and NA in modulating stress reactivity.

关键词： Face recognition   Dictionary learning   Virtual samples   Small sample size problem  

摘要： Face recognition has earned its high reputation for many years since its considerable advances. However, it is still faced with the challenge of the small sample size problem. With the inspiration of the axis-symmetrical property of human faces, we propose a novel virtual sample synthesis strategy to address the issue of limited training samples. It is noteworthy that the novel algorithm can produce symmetry-based virtual face images, in which the pixels in symmetric parts of the face image were exchanged. And it is mathematically very tractable and quite easy to implement. In addition, considering the fact that dictionary learning (DL) based classification methods have excellent learning ability, we incorporate the virtual samples to learn virtual dictionary so as to enhance the accuracy of face recognition. Differing from conventional learning algorithms, the proposed method provides new insights into two crucial parts. Firstly, it proposes an originally creative idea and algorithm to automatically generate symmetry-based virtual samples and obtain virtual dictionary. Secondly, the original dictionary and virtual dictionary are integrated to construct the compound dictionary learning based classification in the way of adaptive weighted fusion. In this paper, we take the axis-symmetrical nature of faces into consideration and design a framework to generate compound dictionary, where more satisfactory classification accuracy can be achieved than the original dictionary learning methods, referred as, the locality-constrained and label embedding dictionary learning (LCLE-DL). Moreover, the experimental results demonstrate the superior performance of the proposed method in comparison with state-of-the-art dictionary learning methods.

关键词： Hyperspectral images   Deep learning   Transfer learning   Semi-supervised learning   Sparse classifier  

摘要： Hyperspectral images usually have small number of labeled samples because of the labeling cost and process difficulty. In conventional classification algorithms, classifier performance is depending on the number training samples. In this study, a deep learning based semi-supervised learning framework is proposed to solve this limited labeled sample size problem by utilizing power of labeled and unlabeled samples. The main aim of the study is constructing a general purpose deep model for a specific hyperspectral sensor type and using the model with little effort for all data sets obtained from this sensor type. In proposed framework, the model is trained with a data set from a hyperspectral sensor subsequently it is fine-tuned and evaluated with another data set acquired from the same sensor. Linearly separable deep features of the evaluation data set are extracted from the fine-tuned general deep model. Additionally, a new data formation method is proposed in the transition from hyperspectral data sub-cubes to the deep neural network input. Besides that, three different clustering methods have been used for selecting the initial labeled samples in the semi-supervised learning phase to observe the effects of the sample selection comparatively. As an another contribution of the study, a new semi-supervised sparse representation classifier (S3 RC) is proposed with labeled and unlabeled sample information by using linearly separable deep features. The performance of the proposed framework is proven by the experimental results with using small sample sizes. (c) 2020 Elsevier B.V. All rights reserved.

关键词： effect modifier   individual participant data (IPD)   meta-analysis   subgroup effect   treatment-covariate interaction  

摘要： Precision medicine research often searches for treatment-covariate interactions, which refers to when a treatment effect (eg, measured as a mean difference, odds ratio, hazard ratio) changes across values of a participant-level covariate (eg, age, gender, biomarker). Single trials do not usually have sufficient power to detect genuine treatment-covariate interactions, which motivate the sharing of individual participant data (IPD) from multiple trials for meta-analysis. Here, we provide statistical recommendations for conducting and planning an IPD meta-analysis of randomized trials to examine treatment-covariate interactions. For conduct, two-stage and one-stage statistical models are described, and we recommend: (i) interactions should be estimated directly, and not by calculating differences in meta-analysis results for subgroups;(ii) interaction estimates should be based solely on within-study information;(iii) continuous covariates and outcomes should be analyzed on their continuous scale;(iv) nonlinear relationships should be examined for continuous covariates, using a multivariate meta-analysis of the trend (eg, using restricted cubic spline functions);and (v) translation of interactions into clinical practice is nontrivial, requiring individualized treatment effect prediction. For planning, we describe first why the decision to initiate an IPD meta-analysis project should not be based on between-study heterogeneity in the overall treatment effect;and second, how to calculate the power of a potential IPD meta-analysis project in advance of IPD collection, conditional on characteristics (eg, number of participants, standard deviation of covariates) of the trials (potentially) promising their IPD. Real IPD meta-analysis projects are used for illustration throughout.

关键词： 常规凝血检验   输血治疗   异位妊娠   大出血   凝血指标  

摘要： 探讨常规凝血检验对于实施输血治疗异位妊娠大出血患者的监测作用与预测作用。方法:选取异位妊娠大出血者100例作为研究主体,结合患者在输血后有无发生不良反应症状,将其分成对照组(n=50)与不良反应组(n=50),分析两组输血治疗前后凝血功能各项指标变化情况。结果:不良反应组凝血酶原时间、凝血酶时间及部分凝血酶时间指标水平均低于治疗前,纤维蛋白原则高于治疗前,对照组各项凝血指标均高于治疗前,不良反应组血红蛋白、血小板、红细胞比容与红细胞指标水平均高于对照组,P<0.05。结论:对于妊娠大出血行输血治疗患者实施常规凝血检查,可有效评估患者在治疗过程中是否发生不良反应,值得广泛推广应用。

关键词： 微生物检验   院内感染   临床作用   感染发生率   影响  

摘要： 分析研究微生物检验对医院感染发生率的临床作用。方法:选择我院2019年2月到2020年3月收治的94例住院患者作为临床研究对象,每组患者47例,对照组47例患者行常规治疗和感染控制,观察组47例患者行常规治疗、感染控制和微生物检验,比较两组患者的院内感染发生率和感染程度,探究微生物检验对医院感染发生率的临床作用[1]。结果:对照组患者的院内感染发生率明显低于对照组,感染程度也显著低于对照组,组间数据比较,P<0.05,差异显著,具有统计学意义。结论:微生物检验对控制院内感染具有积极的作用,其不仅能够降低感染的发生率,还能够降低感染程度,值得在临床中应用和推广。

关键词： Attachment representations   AAI   human service professionals  

摘要： Employee turnover is a pressing problem facing human service professions, especially professionals providing services in the child welfare system. Few studies have examined whether psychological characteristics contribute to turnover. Research suggests that insecure attachment representations may impact burnout and secondary traumatic stress, both common causes of turnover. However, little is known about whether attachment representations vary by years of service among human service providers working with the child welfare system. The purpose of this study was to determine if attachment classifications predicted number of years of service in a sample of 467 service providers working in the child welfare system. Participants completed a demographic questionnaire, including the number of years in the human service profession, and the Adult Attachment Interview (AAI). Multiple regression models were conducted to determine if attachment classification and demographic variables predicted number of years of service. Data revealed that having a dismissing attachment classification predicted more years of service. Having a preoccupied attachment classification predicted fewer years of service. Possible causes and well as implications of these differences are discussed.

关键词： 糖尿病   凝血四项   血脂水平   检验方法   并发症  

摘要： 目的分析研究糖尿病患者凝血四项检验及血脂检验的方法及临床价值。方法选择本院于2016年7月至2018年7月收治的2型糖尿病患者92例作为研究资料,均行凝血四项检验和血脂检验,为观察组,另选择同时间段本院接收的健康体检者92例作为对照组,行凝血四项检验和血脂检验检测,比较两组凝血四项指标(血浆纤维蛋白原、血浆凝血酶原时间、部分凝血活酶时间及凝血酶时间)和血脂指标(三酰甘油、总胆固醇、高密度脂蛋白胆固醇、低密度脂蛋白胆固醇)。结果观察组凝血四项指标血浆纤维蛋白原、血浆凝血酶原时间、部分凝血活酶时间及凝血酶时间与对照组各指标比较均差异显著,P <0.05;观察组三酰甘油,总胆固醇,高密度脂蛋白胆固醇,低密度脂蛋白胆固醇与对照组各指标比较均差异显著,P <0.05。结论针对糖尿病患者加强凝血四项检验和血脂检验对评估其凝血异常情况、血脂异常情况具有较高价值,实现相关并发症尽早发现,尽早防范,利于预后,值得推广。

关键词： 桑国卫   维护保养   操作规范   质量提升   医疗水平   医护人员   精细化   器械  

摘要： 随着医疗水平的提升,各大医院中投入使用的检验类设备种类也越来越多,如何实现更精细化的器械维护保养,是目前医护人员密切关注的问题。《医疗器械检验操作规范第1册》一书的出版为这一问题的解决提供了参考。《医疗器械检验操作规范第1册》一书由任德权和桑国卫2位教授共同编纂完成。