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51.
Presents findings from a study into the attitudes and practices of pandemic-era early career researchers (ECRs) in regard to obtaining access to the formally published scholarly literature, which focused on alternative providers, notably ResearchGate and Sci-Hub. The study is a part of the Harbingers project that has been exploring the work lives and scholarly communication practices of ECRs in pre-pandemic times and during the pandemic, and utilizes data from two rounds of interviews with around 170 ECRs from the sciences and social sciences in eight countries. Findings show that alternative providers, as represented by ResearchGate and Sci-Hub, have become established and appear to be gaining ground. However, there are considerable country- and discipline-associated differences. ECRs' country-specific level of usage of the alternative providers is partly traceable to the adequacy of library provisions, although there are other factors at play in shaping ECRs' attitudes and practices, most notably convenience and time saving, as well as the fact that these platforms have become embedded in the scholarly dashboard. There is a dearth of evidence of the impact of the pandemic on ECRs' ways of obtaining scholarly papers.  相似文献   
52.
The objective of the investigation was to study the application of ultrasound reactor technology (USRT) as a disinfectant for reduction of fungi from sewage effluent. Fungi are carbon heterotrophs that require preformed organic compounds as carbon sources. USRT is an attractive means to improve water quality because of the system simplicity and no production of toxic by-products. An ultrasound reactor produces strong cavitation in aqueous solution causing shock waves and reactive free radicals by the violent collapse of the cavitation bubble. These effects should contribute to the physical disruption of microbial structures and inactivation of organisms. There was significant reduction in fungal growth, with decreased fungal growth with increasing USRT. In this study, ultrasound irradiation at a frequency of 42 kHz was used to expose suspensions of fungi to evaluate the disinfection efficacy of the ultrasound reactor. Also, this study showed that in this system more than 99% reduction of sewage fungi was achieved after 60 min.  相似文献   
53.
Child maltreatment among school children in the Kurdistan Province, Iran   总被引:3,自引:0,他引:3  
OBJECTIVE: This study examines the determinants of three types of child maltreatment: physical maltreatment, mental maltreatment, and child neglect among school children in the Kurdistan Province of Iran. The analysis examines the impact of socioeconomic, familial, demographic, and household dynamic factors on the three child maltreatment outcomes, and compares the differential impact of these factors across the three types of child maltreatment. A greater understanding of the factors associated with child maltreatment has the potential to inform public health interventions aimed at reducing specific forms of maltreatment and at identifying at risk populations. METHODS: Data were collected from 1,370 school students, age 11-18. Separate logistic models are fitted for six binary outcomes examining self-reported experiences of physical maltreatment in the home or school, mental maltreatment in the home or school, and child neglect in the home or school. RESULTS: Male children were more likely to report experiencing any kind of child maltreatment than girls. Residency in a rural area, poor parental relationships and the use of addictive substances by household members were associated with increased odds of reporting child maltreatment. Poor school performance was associated with the reporting of experiencing maltreatment at school. CONCLUSION: Each of the forms of child maltreatment is highly correlated with socioeconomic, demographic, and living condition factors. The results point to the strong influence that familial factors have in shaping a child's likelihood of reporting maltreatment. Characteristics of the mother were associated with maltreatment, but not characteristics of the father. The results highlight a number of mechanisms through which public health interventions may seek to reduce the prevalence of child maltreatment in Kurdistan; different approaches are needed to reduce child maltreatment in the home and school environments.  相似文献   
54.
In ad hoc querying of document collections, current approaches to ranking primarily rely on identifying the documents that contain the query terms. Methods such as query expansion, based on thesaural information or automatic feedback, are used to add further terms, and can yield significant though usually small gains in effectiveness. Another approach to adding terms, which we investigate in this paper, is to use natural language technology to annotate - and thus disambiguate - key terms by the concept they represent. Using biomedical research documents, we quantify the potential benefits of tagging users’ targeted concepts in queries and documents in domain-specific information retrieval. Our experiments, based on the TREC Genomics track data, both on passage and full-text retrieval, found no evidence that automatic concept recognition in general is of significant value for this task. Moreover, the issues raised by these results suggest that it is difficult for such disambiguation to be effective.  相似文献   
55.
Student experience of a scenario-centred curriculum   总被引:1,自引:1,他引:0  
In 2006 UCL implemented new scenario-centred degree programmes in Civil and Environmental Engineering. The new curriculum can be characterised as a hybrid of problem-based, project-based and traditional approaches to learning. Four times a year students work in teams for one week on a scenario which aims to integrate learning from lecture and laboratory classes and to develop generic skills including team working and communication. Student experience of the first two years the old and new curricula were evaluated using a modified Course Experience Questionnaire. The results showed that students on the new programme were motivated by the scenarios and perceived better generic skills development, but had a lower perception of teaching quality and the development of design skills. The results of the survey support the implementation new curriculum but highlight the importance of strong integration between conventional teaching and scenarios, and the challenges of adapting teaching styles to suit.  相似文献   
56.
This paper describes the highlights of an exploratory deep log analysis of journal usage on OhioLINK, conducted as part of the MaxData project. OhioLINK, the original ‘Big Deal’, provides a single digital platform of nearly 6,000 full‐text journals for more than 600,000 people in Ohio and the investigation aimed to assess it after approximately 10 years. The data was generated from an SPSS analysis of the raw (unprocessed) server logs for June 2004 to December 2004. Approximately 1,215,000 items were viewed on campus in October 2004 and 1,894,000 items viewed off campus between June and December 2004. There are a number of usage analyses including: demand and activity; number and name of journal; date of publication; subject/discipline of journal and method of searching/navigating.  相似文献   
57.
Circulating tumor cells (CTCs) are important biomarkers for monitoring tumor dynamics and efficacy of cancer therapy. Several technologies have been demonstrated to isolate CTCs with high efficiency but achieve a low purity from a large background of blood cells. We have previously shown the ability to enrich CTCs with high purity from large volumes of blood through selective capture in microvortices using the Vortex Chip. The device consists of a narrow channel followed by a series of expansion regions called reservoirs. Fast flow in the narrow entry channel gives rise to inertial forces, which direct larger cells into trapping vortices in the reservoirs where they remain circulating in orbits. By studying the entry and stability of particles following entry into reservoirs, we discover that channel cross sectional area plays an important role in controlling the size of trapped particles, not just the orbital trajectories. Using these design modifications, we demonstrate a new device that is able to capture a wider size range of CTCs from clinical samples, uncovering further heterogeneity. This simple biophysical method opens doors for a range of downstream interventions, including genetic analysis, cell culture, and ultimately personalized cancer therapy.  相似文献   
58.
目的:探讨上、下楼梯时附加认知任务,年龄差异(组间)及任务难度(组内)对步态时空及下肢关节协调参数的影响。方法:18位健康老年人为老年组,18位健康大学生为年轻组,各组内均为9男9女,依次接受认知任务测试、上、下楼测试(单任务)及上、下楼合并认知任务测试(双任务)。结果:认知任务方面,两种任务情境下各年龄组上楼回答次数皆显著多于下楼。步态参数方面,两种任务情境下年轻组相对于老年组,以及各年龄组在单任务情境下相对于双任务,皆呈现较短步行时间、较快步行频率、速度及较大步行长度的情形。下肢协调性方面,年轻组上楼过渡时摆动期的膝‐踝协调稳定度在双任务下较单任务差,而处于双任务情境下,年轻组上楼过程中支撑期的膝‐踝协调稳定度比老年组差;年轻组下楼过程中摆动期的髋‐膝协调稳定度在ST 和DT 中都比老年组差,老年组膝‐踝协调稳定度比年轻组差,下楼过渡时,年轻组支撑期髋‐膝协调稳定度在两种任务情境下皆比老年组差。结论:老年人和年轻人会根据任务难度来选择是否专注于认知任务上,此外年轻人因有足够下肢肌力控制而采取较大胆动作策略,导致其上下楼梯时下肢协调稳定度较差,而老年人则趋向选择较保守的策略来维持下肢关节协调稳定度。  相似文献   
59.
This paper deals with the problem of robust stability and robust stabilization for a class of continuous-time singular Takagi–Sugeno fuzzy systems. Sufficient conditions on stability and stabilization are proposed in terms of strict LMI (Linear Matrix Inequality) for uncertain T–S fuzzy models. In order to reduce the conservatism of results developed using quadratic method, an approach based on non-quadratic Lyapunov functions and S-procedure is proposed. Illustrative examples are given to show the effectiveness of the given results.  相似文献   
60.
Carboxylate-modified gold nanoparticles (GNPs) were synthesized in a simple one-step process based on the reduction of tetrachloroauric acid by aspartic acid in water. GNPs were identified by UV–Vis spectroscopy, dynamic light scattering (DLS) and transmission electron microscopy. Conjugation of protein molecules with functionalized nanoparticles was performed through electrostatic interaction. The GNP–protein conjugates were characterized by gel electrophoresis. The interaction between functionalized GNPs and protein molecules lead to conformational transition of protein structure after conjugation of protein with GNPs. This process was investigated by fluorescence spectroscopy and circular dichroism spectroscopy.  相似文献   
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