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111.
Few data exist on gender-typed and gender-segregated play in hunter-gatherer societies, despite their unique demographic and cultural features which may influence children’s gendered play. Using naturalistic observations of Hadza (N = 46, 41% female) and BaYaka (N = 65, 48% female) hunter-gatherer 3- to 18-year-olds from Tanzania and the Republic of Congo, we showed that access to playmates was negatively associated with playing in mixed-gender groups. Young boys did not engage in more rough-and-tumble play than girls, but adolescent boys participated in this type of play more than adolescent girls. Children were also more likely to participate in work-themed play which conformed to gender norms within their society. Findings are discussed within the context of gendered division of labor, child autonomy, and demography.  相似文献   
112.
To cope with ambiguous and/or underspecified queries, search result diversification (SRD) is a key technique that has attracted a lot of attention. This paper focuses on implicit SRD, where the subtopics underlying a query are unknown. Many existing methods appeal to the greedy strategy for generating diversified results. A common practice is using a heuristic criterion for making the locally optimal choice at each round. As a result, it is difficult to know whether the failures are caused by the optimization criterion or the setting of parameters. Different from previous studies, we formulate implicit SRD as a process of selecting and ranking k exemplar documents through integer linear programming (ILP). The key idea is that: for a specific query, we expect to maximize the overall relevance of the k exemplar documents. Meanwhile, we wish to maximize the representativeness of the selected exemplar documents with respect to the non-selected documents. Intuitively, if the selected exemplar documents concisely represent the entire set of documents, the novelty and diversity will naturally arise. Moreover, we propose two approaches ILP4ID (Integer Linear Programming for Implicit SRD) and AP4ID (Affinity Propagation for Implicit SRD) for solving the proposed formulation of implicit SRD. In particular, ILP4ID appeals to the strategy of bound-and-branch and is able to obtain the optimal solution. AP4ID being an approximate method transforms the target problem as a maximum-a-posteriori inference problem, and the message passing algorithm is adopted to find the solution. Furthermore, we investigate the differences and connections between the proposed models and prior models by casting them as different variants of the cluster-based paradigm for implicit SRD. To validate the effectiveness and efficiency of the proposed approaches, we conduct a series of experiments on four benchmark TREC diversity collections. The experimental results demonstrate that: (1) The proposed methods, especially ILP4ID, can achieve substantially improved performance over the state-of-the-art unsupervised methods for implicit SRD. (2) The initial runs, the number of input documents, query types, the ways of computing document similarity, the pre-defined cluster number and the optimization algorithm significantly affect the performance of diversification models. Careful examinations of these factors are highly recommended in the development of implicit SRD methods. Based on the in-depth study of different types of methods for implicit SRD, we provide additional insight into the cluster-based paradigm for implicit SRD. In particular, how the methods relying on greedy strategies impact the performance of implicit SRD, and how a particular diversification model should be fine-tuned.  相似文献   
113.
ABSTRACT

The effectiveness of 8-week force-velocity optimised training was assessed in highly trained professional rugby league athletes. Players (age 24 ± 3 years; body mass 94.9 ± 21.6 kg; height 181.3 ± 6.0 cm) were strength-matched and assigned to a force-velocity optimised group (OP; n = 15) or a general strength-power group (GP; n = 14). Tests included 10-m, 20-m sprints, 3 repetition-maximum squat and squat jumps over five load conditions to ascertain vertical force-velocity relationship. ANCOVA revealed there was a group effect for force-velocity deficit (P < 0.001), with the OP two-fold greater than the GP group (OP pre: 51.13 ± 31.42%, post: 62.26 ± 31.45%, GP pre: 33.00 ± 19.60%, post: 31.14 ± 31.45%, P < 0.001). There were further group effects for 3RM squat (OP pre: 151.17 ± 22.95 kg, post: 162.17 ± 24.16 kg, GP pre: 156.43 ± 25.07 kg, post: 163.39 ± 25.39 kg, P < 0.001), peak power (OP pre: 3195 ± 949 W, post: 3552 ± 1033 W, GP pre: 3468 ± 911 W, post: 3591 ± 936 W, P < 0.001), and SJ (OP pre: 39.79 ± 7.80 cm, post: 42.69 ± 7.83 cm, GP pre: 40.44 ± 6.23 cm, post: 41.14 ± 5.66 cm, P < 0.001). Prescribing F-V deficit training is superior for improving physical performance within highly trained RL players.  相似文献   
114.
In this article, I do two things. First, I describe and evaluate progress that has been made to date on implementing five recommendations made by the author to the leadership of Elliot Lake Public Library in 2014, intended to assist in disaster recovery efforts following the destruction of the library in an anthropogenic disaster in 2012. Second, I provide three revised recommendations, this time intended to assist library leadership address some continuing challenges that are preventing the complete recovery of the library, and ultimately, negatively impacting the effectiveness of the library within the community.  相似文献   
115.
116.
This study examined factors that might affect researchers' willingness to collaborate with a specific researcher and the priorities given to those factors. In addition, it investigated how researchers determined the ownership of collaborative project data and how they determined the order of authorship on collaborative publications in condensed matter physics. In general, researchers rated their intrinsic motivations the highest, such as the quality of ideas a potential collaborator might have and their satisfaction with a past collaboration, followed by their extrinsic motivations, such as the complementary knowledge, skills, or resources the collaborator could provide. In addition, researchers who had a greater number of collaborative projects and researchers who had served as a project PI or co-PI valued the deep-level, personality-related characteristics of a collaborator higher than did those who had not. Younger researchers were more risk averse and more concerned with a collaborator's reputation and the possible cost of a collaboration decision. Additionally, younger researchers indicated more often than older researchers that they did not know whether their project teams followed any rules or norms or engaged in negotiation to determine the order of authorship on collaborative publications.  相似文献   
117.
118.
This paper reviews research on students’ usage of university counselling services across countries and their demographic and psychological characteristics. In doing so, emphasis is given to reported distinctions between local and international university students. Utilisation rates, encouraging factors and barriers to utilisation, presenting problems, and methodological problems with existing studies are each examined. The findings suggest that only a minority of between 2% and 4% of university students access such services, with females being more likely to use them than males. International students in particular underutilise these services, and this is primarily due to such students’ preference for seeking help from family or friends over outside sources. When students do seek assistance, their presenting issues most commonly involve symptoms of depression or anxiety, as well as academic and relationship difficulties.  相似文献   
119.
Literature has shown that on-the-job professional development programs are most beneficial when they are long-term, focused on students’ learning, and linked to the curricula. We hypothesized that the higher the control teachers have over job professional development processes, and the greater the resemblance of these processes to the typical teaching culture in classrooms, the greater the teachers’ satisfaction with job professional development processes. The findings of this study demonstrate that the main factors affecting teachers’ satisfaction with the instructional programs are related to their desire to maintain instructional processes “close to home”, and to shape these processes in accordance with their needs and expectations. The implications of the study are discussed with relation to decision-makers in the school setting and at the local authorities’ level.  相似文献   
120.
Twenty five class teachers completed a "Strengths and Difficulties" assessment for 523 children aged from 7 to 11 years of age. Children self-completed a 39-item "My Life in School" questionnaire. One third of the sample were self-reported victims of bullying behaviour. Boys with poor prosocial skills, emotional problems and general difficulties with social interaction, expression of emotion and hyperactivity were at greatest risk of being bullied. There was no significant effect of age. The data support previous research findings that gender influences the prevalence of bullying but not that younger children are more vulnerable. This study provides new evidence that teachers recognise social behaviour and interactions that can significantly affect whether primary school children are bullied.  相似文献   
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