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71.
Multi-document discourse parsing aims to automatically identify the relations among textual spans from different texts on the same topic. Recently, with the growing amount of information and the emergence of new technologies that deal with many sources of information, more precise and efficient parsing techniques are required. The most relevant theory to multi-document relationship, Cross-document Structure Theory (CST), has been used for parsing purposes before, though the results had not been satisfactory. CST has received many critics because of its subjectivity, which may lead to low annotation agreement and, consequently, to poor parsing performance. In this work, we propose a refinement of the original CST, which consists in (i) formalizing the relationship definitions, (ii) pruning and combining some relations based on their meaning, and (iii) organizing the relations in a hierarchical structure. The hypothesis for this refinement is that it will lead to better agreement in the annotation and consequently to better parsing results. For this aim, it was built an annotated corpus according to this refinement and it was observed an improvement in the annotation agreement. Based on this corpus, a parser was developed using machine learning techniques and hand-crafted rules. Specifically, hierarchical techniques were used to capture the hierarchical organization of the relations according to the proposed refinement of CST. These two approaches were used to identify the relations among texts spans and to generate multi-document annotation structure. Results outperformed other CST parsers, showing the adequacy of the proposed refinement in the theory.  相似文献   
72.
Tumor lysis syndrome has been observed in patients with malignancies with high cellular burden and high cell turnover, tumor sensitive to therapy, especially after initiating medical treatment. It very rarely occurs spontaneously. The case described here is of 6 months male infant who presented with fever since 1 month and loose stools associated with blood since 15 days. The laboratory investigations showed lactate dehydrogenase (LDH) of 6,192 IU/L and serum uric acid 18.2 mg/dl along with pancytopenia. The infant presented with electrolyte abnormalities and renal failure.  相似文献   
73.
Isolation and enrichment of low-abundant particles are essential steps in many bio-analytical and clinical applications. In this work, the capability of an insulator-based dielectrophoresis (iDEP) device for the detection and stable capture of low abundant polystyrene particles and yeast cells was evaluated. Binary and tertiary mixtures of particles and cells were tested, where the low-abundant particles had concentration ratios on the order of 1:10 000 000 compared to the other particles present in the mixture. The results demonstrated successful and stable capture and enrichment of rare particles and cells (trapping efficiencies over 99%), where particles remained trapped in a stable manner for up to 4 min. A device with four reservoirs was employed for the separation and enrichment of rare particles, where the particles of interest were first selectively concentrated and then effectively directed to a side port for future collection and analysis. The present study demonstrates that simple iDEP devices have appropriate screening capacity and can be used for handling samples containing rare particles; achieving both enrichment and isolation of low-abundant particles and cells.  相似文献   
74.
Currently, medical education context poses different challenges to anatomy, contributing to the introduction of new pedagogical approaches, such as computer-assisted learning (CAL). This approach provides insight into students' learning profiles and skills that enhance anatomy knowledge acquisition. To understand the influence of anatomy CAL on spatial abilities, a study was conducted. A total of 671 medical students attending Musculoskeletal (MA) and Cardiovascular Anatomy (CA) courses, were allocated to one of three groups (MA Group, CA Group, MA + CA Group). Students' pre-training and post-training spatial abilities were assessed through Mental Rotations Test (MRT), with scores ranging between 0-24. After CAL training sessions, students' spatial abilities performance improved (9.72 ± 4.79 vs. 17.05 ± 4.57, P < 0.001). Although male students in both MA Group and CA Group show better baseline spatial abilities, no sex differences were found after CAL training. The improvement in spatial abilities score between sessions (Delta MRT) was correlated with Musculoskeletal Anatomy training sessions in MA Group (r = 0.333, P < 0.001) and MA + CA Group (r = 0.342, P < 0.001), and with Cardiovascular Anatomy training sessions in CA Group (r = 0.461, P = 0.001) and MA + CA Group (r = 0.324, P = 0.001). Multiple linear regression models were used, considering the Delta MRT as dependent variable. An association of Delta MRT to the amount of CAL training and the baseline spatial abilities was observed. The results suggest that CAL training in anatomy has positive dose-dependent effect on spatial abilities.  相似文献   
75.
This paper introduces a framework and methodology for establishing indicators and metrics in order to assess the quality and performance of one-stop e-Government service offerings. The set of quality and performance indicators and metrics proposed has been derived in an outcomes assessment approach, based on the perspectives of e-Government service providers and end-users and following a goal-question-metric line of work that departs from some key quality and performance benefits. A methodology that employs the proposed framework to set improvement targets according to alternative scenarios is presented, and a strategy is elaborated for analyzing root causes of potential quality and performance shortcomings and undertaking appropriate countermeasures. Some results of application in a real case study, in the context of an EU-funded R&D project, are also provided. Finally, recommendations are given about usefulness of the proposed approach for e-Government service providers, as well as policy and decision-makers, and directions of future work are discussed in order to enhance the conceptual coverage of this approach, while at the same time not compromising its simplicity of application and generality of purpose.  相似文献   
76.
美国图书馆协会的<职业道德规范声明>提出了以图书馆事业为中心的具体原则,其<图书馆权利法案>则明确了图书馆的责任和义务.目前,美国社会和政治环境的变化为图书馆职业带来了越来越多的忧虑和压力."9·11"后出台的<爱国者法案>明显与图书馆职业道德规范中所阐述的重要原则相冲突.因此,美国图书馆协会决心抵制<爱国者法案>对知识、信息自由开放以及行使个人隐私权的限制.  相似文献   
77.
Reflexivity is a learning process that, through questioning and critically monitoring objectives and methods in use, promotes a change of habits and routines and, in so doing, fosters organizational performance and innovativeness. This paper looks at the contribution of team reflexivity to enhancing openness to innovation, and the mediating role of individual and team involvement. Specifically we tested whether affective commitment (Study 1, n=156) and a team climate of support for innovation (Study 2, n=152) facilitate reflexivity processes in promoting organizational openness to innovation. Overall, results confirmed that reflexivity enhances innovativeness, and this relationship is mediated by a high degree of involvement that increases the motivation of teammates and their engagement in innovation processes.  相似文献   
78.
79.
The late nineteenth century American mass circulation press developed a style of ‘new journalism’ that gave rise to celebrity journalism. It is widely accepted that this new approach to reporting replaced news values with entertainment as a consequence of the need to cater to the tastes of a mass readership and this is seen to explain the incredible innovations that occurred in the press in the US at the time (Ponce de Leon; Roggenkamp; Tebbel; Turner; Schudson Discovering the News). This article questions this version of American press history by arguing that those papers also had to appeal to the politics of poor immigrants and the working class and that the conventions associated with celebrity overlapped and often coincided with a ‘radical’ populist campaigning style of reporting that was as important (and at times, more important) to building and sustaining mass readerships.  相似文献   
80.

Constructing explanations of scientific concepts is one of the most frequent strategies used in the science classroom and is a high-leverage teaching practice. This study analysed the explanations provided by student teachers in STEM areas from a socio-materiality perspective focused on verbal and nonverbal language and representations. The study was conducted in a hybrid research format by scholars and a preservice teacher. First, the study compared the representational elements used by 86 student teachers to construct explanations about various concepts in a roleplay setting. Next, a positioning analysis was done by a preservice teacher, to a selection of five of these explanations focused on the concept of “force”. The positioning analysis highlighted the embedded voices in the construction of explanations, with a focus on the intersection between science and language. The results showed that the student teachers created explanations as static artefacts, mainly using examples, graphs and images to clarify the concepts. The voices of learners and scientists were mostly absent from the explanations, which led to the presentation of explanations in STEM areas as finished and unquestionable artefacts, with references neither to nature nor to the history of science. We reflect on the meanings attributed to learning to be a practitioner in the context of interconnecting science and language through explanations, as a process of meaning (re)production within the classroom. Implications for teacher education are discussed in order to enhance student teachers’ awareness about constructing knowledge by enacting explanations in the science classroom.

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