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991.
R D Tschirgi 《Bulletin of the Medical Library Association》1973,61(1):1-3
The contemporary criterion of professional success for an academic scientist is primarily his rate of publication in scholarly journals. This distorted and relatively uncritical valuation of the communication aspects of science has promoted an increasing deluge of increasingly redundant, dilute, and trivial publications. In a modern well-equipped research laboratory, producing publishable new observations can be a fairly simple process in many fields, especially if the relevance of the observations to either the advancement of the scientific world view or to a social need is inconsequential. This easy currency of rampant new observations has obscured the creative process of formulating new scientific concepts which are the ultimate refined product of the scientific enterprise. Perhaps scientists should talk less and think more. 相似文献
992.
Mengwen?Liu Yi?FangEmail author Alexander?G.?Choulos Dae?Hoon?Park Xiaohua?Hu 《Information Retrieval》2017,20(6):575-605
Product reviews have become an important resource for customers before they make purchase decisions. However, the abundance of reviews makes it difficult for customers to digest them and make informed choices. In our study, we aim to help customers who want to quickly capture the main idea of a lengthy product review before they read the details. In contrast with existing work on review analysis and document summarization, we aim to retrieve a set of real-world user questions to summarize a review. In this way, users would know what questions a given review can address and they may further read the review only if they have similar questions about the product. Specifically, we design a two-stage approach which consists of question selection and question diversification. For question selection phase, we first employ probabilistic retrieval models to locate candidate questions that are relevant to a given review. A Recurrent Neural Network Encoder–Decoder is utilized to measure the “answerability” of questions to a review. We then design a set function to re-rank the questions with the goal of rewarding diversity in the final question set. The set function satisfies submodularity and monotonicity, which results in an efficient greedy algorithm of submodular optimization. Evaluation on product reviews from two categories shows that the proposed approach is effective for discovering meaningful questions that are representative of individual reviews. 相似文献
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This study examined whether or not activity monitor data collected as part of a typical 7-day physical activity (PA) measurement protocol can be expected to be missing at random. A total of 315 participants (9–18 years) each wore a SenseWear Armband monitor for 7 consecutive days. Participants were classified as “compliant” (86 boys and 124 girls) if they had recorded accelerometer data during 70% or more of the predefined awake time (7 AM–10 PM) on four different days; and “non-compliant” (44 boys and 51 girls) when not meeting these criteria. Linear mixed models were used to examine differences in energy expenditure (EE) levels by compliance across 10 different time periods. The results indicated that non-compliant girls were older (13.4 ± 2.9 vs. 12.2 ± 2.5) and taller (156.8 ± 10.3 vs. 152.8 ± 11.3) than their same gender compliant peers (P < .05). Comparisons of EE rates at segmented portions of the day revealed no differences between compliant and non-compliant groups (P ≥ .05). Differences in EE ranged from ?0.32 kcal · kg?1 · h?1 (before school time) to 0.62 kcal · kg?1 · h?1 (physical education class) in boys and ?0.39 kcal · kg?1 · h?1 (transportation from school) to 0.37 kcal · kg?1 · hour?1 (recess) in girls. The results showed that compliant and non-compliant individuals differed in a few demographic characteristics but exhibited similar activity patterns. This suggests that data were considered to be missing at random, but additional work is needed to confirm this observation in a representative sample of children using other types of activity monitors and protocols. 相似文献
995.
Debi de Prasad C. R. Maity de Swapan 《Indian journal of clinical biochemistry : IJCB》1993,8(1):71-72
Urinary excretion of 3 methoxy-4-hydroxy phenyl glycol (MHPG) and 3-methoxy-4-hydroxy mandelic acid (VMA) were estimated in 18 Post-Japanese Encephalitis depressive patients and 20 unipolar depressive patients to determine their biochemical differences. Both the metabolites were low in the former group in comparison to the later group, indicating that the metabolic events in respect to catecholamine turn over are different in two disorders. 相似文献
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Jennifer R. Warren Michael L. Hecht David A. Wagstaff Elvira Elek Khadidiatou Ndiaye Patricia Dustman Flavio F. Marsiglia 《Journal of Applied Communication Research》2006,34(2):209-227
This study sought to determine if exposure to two communication-oriented activities, videotapes and public service announcements, accounts for changes in substance use among adolescents participating in the Drug Resistance Strategies Project's keepin' it REAL adolescent substance use prevention curriculum. Middle-school students (4,734, 72% Latino) responded to questionnaires related to these analyses. An analysis of covariance (ANCOVA) model was fit separately to six substance use outcomes. The results suggested that intervention students who saw four or five videos engaged in less substance use in the past month than did students who saw fewer videos. Having seen the PSAs one or more times did not predict the reported change in substance use. 相似文献
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