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951.
As bibliographical classification of published journal items affects the denominator in this equation, we investigated how
the numerator and denominator of the impact factor (IF) equation were generated for representative journals in two categories
of the Journal Citation Reports (JCR). We performed a full text search of the 1st-ranked journal in 2004 JCR category “Medicine, General and Internal” (New England Journal of Medicine, NEJM, IF = 38.570) and 61st-ranked journal (Croatian Medical Journal, CMJ, IF = 0.690), 1st-ranked journal in category “Multidisciplinary Sciences” (Nature, IF = 32.182) and journal with a relative rank of CMJ (Anais da Academia Brasileira de Ciencias, AABC, IF = 0.435). Large journals published more items categorized by Web of Science (WoS) as non-research items (editorial material,
letters, news, book reviews, bibliographical items, or corrections): 63% out of total 5,193 items in Nature and 81% out of 3,540 items in NEJM, compared with 31% out of 283 items in CMJ and only 2 (2%) out of 126 items in AABC. Some items classified by WoS as non-original contained original research data (9.5% in Nature, 7.2% in NEJM, 13.7% in CMJ and none in AABC). These items received a significant number of citations: 6.9% of total citations in Nature, 14.7% in NEJM and 18.5% in CMJ. IF decreased for all journals when only items presenting original research and citations to them were used for IF calculation.
Regardless of the journal’s size or discipline, publication of non-original research and its classification by the bibliographical
database have an effect on both numerator and denominator of the IF equation.
Preliminary results of the study were presented at the 2006 ORI Research Conference on Research Integrity, Tampa, FL, December
1–3, 2006. 相似文献
952.
When mobile organisms are spatially disoriented, for instance by rapid repetitive movement, they must re-establish orientation. Past research has shown that the geometry of enclosing spaces is consistently used for reorientation by a wide variety of species, but that non-geometric features are not always used. Based on these findings, some investigators have postulated a species-universal 'geometric module' that is transcended by the acquisition of spatial language at 6 years. This conclusion has been challenged, however, by findings that children as young as 18 months actually do use features to reorient in larger enclosures than those used in the original experiments. The reason for the room size effect is explored here in five experiments. Collectively, the data on age at which features are first used point to the importance of both restriction of movement in the small space and the fact that features are closer in the small space. In addition, success is seen at younger ages when the target object is adjacent to the feature. These results favor an adaptive combination model of spatial reorientation over a 'module-plus-language' view. 相似文献
953.
Preschoolers' lack of cognitive flexibility has often been attributed to perseverative processing. This study investigates alternative potential sources of difficulty such as deficits in activating previously ignored information and in maintaining currently relevant information. In Experiment 1, a new task tapping attentional switching was designed to isolate the difficulty of overriding an initial representation, that is, perseverative processing ('Perseveration' version), and the difficulty of activating a previously ignored representation, that is, activation deficit ('Activation-deficit' version). Three-year-olds' performance suggested that inflexibility may primarily stem from an activation deficit. Control experiments confirmed that the difficulty of the 'Activation-deficit' version could not be attributed to the effect of attraction to novelty. In Experiment 2, 'distraction' errors, alleged to reflect a failure to maintain a relevant representation, and 'perseverative' errors were distinguished. The results highlighted the important role of representation maintenance in flexibility. The present study indicates that preschoolers' lack of cognitive flexibility is multi-determined and prompts us to reconsider the role of perseveration. 相似文献
954.
Previous studies indicated various nonverbal behaviors including eye contact of women are associated with men's approach; however, duration of the eye contact was not tested. In Exp. 1, a female confederate established eye-contact of 3 sec. or 1 sec. with a man when entering a bar. Duration of returned glance was the dependent variable. Analysis showed mean duration of the return glance was statistically shorter in the 1-sec. condition. In Exp. 2, the confederate made eye contact with a man and looked at him less than 1 sec., 2 sec., or 4 sec. The presence versus absence of smile was the dependent variable. Longer duration of eye contact was associated with an increase of smiling. 相似文献
955.
956.
It has been suggested that language impairment in autism is behaviorally, neurobiologically, and etiologically related to specific language impairment (SLI). In this article, the authors review evidence at each level and argue that the vast majority of data does not support the view that language impairment in autism can be explained in terms of comorbid SLI. The authors make recommendations for how this debate might be resolved and suggest a shift in research focus. They recommend that researchers concentrate on those aspects of language impairment that predominate in each disorder rather than on those comparatively small areas of potential overlap. 相似文献
957.
Offshore orientation in marine mammals is still a mystery. For visual orientation during night-time foraging and travelling
in the open seas, seals cannot rely on distant terrestrial landmarks, and thus might use celestial cues as repeatedly shown
for nocturnally migrating birds. Although seals detect enough stars to probably allow for astronavigation, it was unclear
whether they can orient by the night sky. The widely accepted cognitive mechanism for bird night-time orientation by celestial
cues is a time-independent star compass with learned geometrical star configurations used to pinpoint north as the rotational
centre of the starry sky while there is no conclusive evidence for a time-compensated star compass or true star navigation.
Here, we present results for two harbour seals orienting in a custom made swimming planetarium. Both seals learned to highly
accurately identify a lodestar out of a pseudo-randomly oriented, realistic projection of the northern hemisphere night sky.
Providing the first evidence for star orientation capability in a marine mammal, our seals’ outstanding directional precision
would allow them to steer by following lodestars of learned star courses, a celestial orientation mechanism that has been
known to be used by Polynesian navigators but has not been considered for animals yet. 相似文献
958.
Using an ecological framework, the authors explore the reasons for peer discrimination and harassment reported by many Chinese American youth. They draw on longitudinal data collected on 120 first- and second-generation Chinese American students from two studies conducted in Boston and New York. Our analyses suggested that reasons for these experiences of harassment lay with the beliefs about academic ability, the students' immigrant status and language barriers, within-group conflicts, and their physical appearance that made them different from other ethnic minority or majority students. Implications and future research are also discussed. 相似文献
959.
This chapter provides an overview of non family contexts that shape the development and adjustment of children and youth from immigrant families. It also describes the four chapters in this special issue that focus on peer, network, legal, and institutional contexts that influence the lives of immigrant parents and their children. Directions for future research on the social contexts of development in immigrant families are discussed. 相似文献
960.