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1.
Based upon suggestions that the two cerebral hemispheres may be differentially involved in the perception and regulation of autonomic activity, three studies were designed to explore differences in the relationship between left versus right hand finger tapping and the heartbeat. In each study, right-handed subjects were asked to tap with either their left versus right forefingers regularly at the rate of approximately once per second. When the time from the R-spike immediately preceding their tap to the tap was examined, a significant difference between the two hands was obtained in two of the studies, with the left hand tapping closer to the last R-spike compared with the right. A variety of additional conditions in the experiments suggest that this effect may depend upon tapping rhythmically. The implications of these findings for the differential role of the left and right hemispheres in the perception and regulation of cardiac activity are considered.  相似文献   
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【目的】 研究国际主要学术出版技术服务商面向科技期刊服务的业务特征,为国内科技期刊行业发展提供参考。【方法】 通过对13家典型的国际学术出版技术服务商进行信息收集和整理,总结其业务范围及产品和服务方案,并结合国内同类机构进行比较分析。结合文献探讨专业化的学术出版技术服务商的发展趋势。【结果】 国际学术出版技术服务商的业务范围覆盖学术出版全过程,近年来呈现服务领域不断延伸、服务内容更加分工细化的趋势。国际学术出版技术服务商充分运用数字信息技术,其规模和业务范围大于国内同类企业。【结论】 利用好技术手段,发展成熟完善的学术出版技术服务产业,有利于科技期刊将资源集中于核心内容,有利于提高科技期刊整体质量。  相似文献   
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This study analyzes the anthropometric and physiological characteristics of junior cyclists within different cycling specialties and different performance levels. One hundred and thirty‐two junior riders (16.8 ± 0.6 years, 177 ± 6 cm, 66.3 ± 6.7 kg) were tested for anthropometric, aerobic and anaerobic parameters. Cyclists were classified within specialties [uphill (UH) flat terrain (FT) all terrain (AT) and sprint (SP)] and performance levels, based on a seasonal ranking [low level (LL) medium level (ML) and high level (HL)]. The results of the two‐way analysis of variance showed that FT and SP have greater body dimensions than UH and AT (P<0.001). Concerning the relative aerobic parameters, AT and UH have higher values (P<0.001) than FT and SP [maximal oxygen uptake (VO2max): 69.4 ± 3.6, 67.5 ± 5.0, 62.8 ± 4.5 and 61.9 ± 4.1 mL/kg/min, respectively] while absolute parameters resulted higher for FT and AT (P≤0.008). The relative power produced in the 5 s test was higher (P<0.001) for AT and SP than FT and UH (16.7 ± 1.1, 16.6 ± 0.6, 14.9 ± 1.7 and 14.4 ± 1.7 W/kg, respectively). Concerning the performance level, only the age and the aerobic parameters resulted differently within levels (VO2max: HL=67.3 ± 4.9, ML=65.5 ± 5.1 and LL=63.3 ± 5.2 mL/kg/min), with the highest values for HL (P≤0.007). In conclusion, juniors are specialized in the same way as professional cyclists and the aerobic characteristics are confirmed as significant in the performance level assessment.  相似文献   
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The dietary specialist fruit fly Drosophila sechellia has evolved resistance to the secondary defence compounds produced by the fruit of its host plant, Morinda citrifolia. The primary chemicals that contribute to lethality of M. citrifolia are the medium‐chain fatty acids octanoic acid (OA) and hexanoic acid. At least five genomic regions contribute to this adaptation in D. sechellia and whereas the fine‐mapped major effect locus for OA resistance on chromosome 3R has been thoroughly analysed, the remaining four genomic regions that contribute to toxin resistance remain uncharacterized. To begin to identify the genetic basis of toxin resistance in this species, we removed the function of well‐known detoxification gene families to determine whether they contribute to toxin resistance. Previous work found that evolution of cytochrome P450 enzymatic activity or expression is not responsible for the OA resistance in D. sechellia. Here, we tested the role of the two other major detoxification gene families in resistance to Morinda fruit toxins – glutathione‐S‐transferases and esterases – through the use of the pesticide synergists diethyl maleate and tribufos that inhibit the function of these gene families. This work suggests that one or more esterase(s) contribute to evolved OA resistance in D. sechellia.  相似文献   
6.
Extant neurobiological theories of dyslexia appear fractional in focusing on isolated brain regions, mechanisms, and functional pathways. A synthesis of current research shows support for an Interactive Specialization (IS) model of dyslexia involving the dysfunctional orchestration of a widely-distributed, attentionally-controlled, hierarchical, and interhemispheric circuit of intercommunicating neuronal networks. This circuitry is comprised principally of the frontostriatal-parietal cognitive control system of networks, the posterior corpus callosum, and the left arcuate fasciculus. During development, the coalescence of these functionally specialized regions, acting together, may be essential to preventing the core phonemic and phonological processing deficits defining the dyslexic phenotype. Research demonstrating an association of each with processing phonology presents the foundational outline for a comprehensive, integrative theory of dyslexia and suggests the importance of inclusive remedial efforts aimed at promoting interactions among all three networking territories.  相似文献   
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