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41.
Negro Catherine Del; Kreutzer Michel; Gahr Manfred 《Canadian Metallurgical Quarterly》2000,114(3):526
During the breeding season under long-day conditions, male canaries sing sexually attractive songs and females respond behaviorally to such songs. This study assessed whether auditory response properties of neurons in nucleus HVc of female and male canaries are tuned to sexually salient song features: special song phrases and canary song segmentation. In sexually receptive female canaries, neurons responded to special song phrases with a decreased spike rate and were sensitive to canary song segmentation. The nonreceptive females showed no clear response to special song phrases. In females on short days, neurons responded to song phrases with an increase in activity. In males on long days, they exhibited phasic responses after the phrase onset, whatever the song phrase and song segmentation. This study demonstrates both a plasticity in relation to females' sexual responsiveness and a sexual dimorphism in the auditory processing performed in the HVc. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
42.
Baptiste Demey Marine Bentz Vronique Descamps Virginie Morel Catherine Francois Sandrine Castelain Francois Helle Etienne Brochot 《International journal of molecular sciences》2022,23(13)
Background: Bkv-miR-B1-5p is a viral micro-RNA (miRNA) specifically produced during BK polyomavirus (BKPyV) replication. Recent studies have suggested using bkv-miR-B1-5p as a biomarker to monitor viral infection and predict complications in kidney transplant patients. To identify the technical limitations of this miRNA quantification in biological samples, knowledge of its stability and distribution in the extracellular compartment is necessary. Moreover, a proof of concept for using bkv-miR-B1-5p as a biomarker of active replication in chronic infection is still missing in the published literature. Methods: The stability of bkv-miR-B1-5p was evaluated in samples derived from cell cultures and in urine from BKPyV-infected kidney transplant recipients. The miRNA was quantified in different fractions of the extracellular compartment, including exosomes, and protein binding was evaluated. Finally, we developed an in vitro model for chronic culture of BKPyV clinical isolates to observe changes in the bkv-miR-B1-5p level during persistent infections. Results: Bkv-miR-B1-5p is a stable biomarker in samples from humans and in vitro experiments. Marginally associated with the exosomes, most of the circulating bkv-miR-B1-5p is bound to proteins, especially Ago2, so the miRNA quantification does not require specific exosome isolation. The bkv-miR-B1-5p level is predictable of viral infectivity, which makes it a potential specific biomarker of active BKPyV replication after kidney transplantation. 相似文献
43.
A parallel method for the dynamic partitioning of unstructured meshes is described. The method introduces a new iterative optimization technique known as relative gain optimization which both balances the workload and attempts to minimize the interprocessor communications overhead. Experiments on a series of adaptively refined meshes indicate that the algorithm provides partitions of an equivalent or higher quality to static partitioners (which do not reuse the existing partition) and much more rapidly. Perhaps more importantly, the algorithm results in only a small fraction of the amount of data migration compared to the static partitioners. 相似文献
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45.
Ben Shneiderman Catherine Plaisant Rodrigo Botafogo Don Hopkins William Weiland 《New Review of Hypermedia and Multimedia》2013,19(2):101-117
Since browsing hypertext can present a formidable cognitive challenge, user interface design plays a major role in determining acceptability. In the Unix workstation version of Hyperties, a research-oriented prototype, we focussed on design features that facilitate browsing. We first give a general overview of Hyperties and its markup language. Customizable documents can be generated by the conditional text feature that enables dynamic and selective display of text and graphics. In addition we present: — an innovative solution to link identification: pop-out graphical buttons of arbitrary shape. — application of pie menus to permit low cognitive load actions that reduce the distraction of common actions, such as page turning or window selection. — multiple window selection strategies that reduce clutter and housekeeping effort. We preferred piles-of-tiles, in which standard-sized windows were arranged in a consistent pattern on the display and actions could be done rapidly, allowing users to concentrate on the contents. 相似文献
46.
Stein Catherine H.; Abraham Kristen M.; Bonar Erin E.; Leith Jaclyn E.; Kraus Shane W.; Hamill Alexis C.; Gumber Shinakee; Hoffmann Erica; Fogo Wendy R. 《Canadian Metallurgical Quarterly》2011,25(3):449
The present intergenerational study examined the perceived impact of the recent U.S. economic crisis on a sample of 68 young adult–parent dyads. The relative contribution of perceived economic pressure, reports of adult child–parent relationship quality, and concerns about the economic future in accounting for variation in self-reports of psychological distress for adult children and their middle-aged parents were examined. Parents' concerns about their children's economic future accounted for variation in their reports of anxiety and depressed mood above and beyond that of perceived economic pressures and their views of the parent–child relationship. In contrast, for young adults, reports of personal economic pressure were generally related to self-reported anxiety and depressed mood. Implications of findings for research and practice are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
47.
Demany Laurent; Semal Catherine; Pressnitzer Daniel 《Canadian Metallurgical Quarterly》2011,37(2):597
Listeners had to compare, with respect to pitch (frequency), a pure tone (T) to a combination of pure tones presented subsequently (C). The elements of C were either synchronous, and therefore difficult to hear out individually, or asynchronous and therefore easier to hear out individually. In the “present/absent” condition, listeners had to judge if T reappeared in C or not. In the “up/down” condition, the task was to judge if the element of C most similar to T was higher or lower than T. When the elements of C were synchronous, the up/down task was found to be easier than the present/absent task; the converse result was obtained when the elements of C were asynchronous. This provides evidence for a duality of auditory comparisons between tone frequencies: (1) implicit comparisons made by automatic and direction-sensitive “frequency-shift detectors”; (2) explicit comparisons more sensitive to the magnitude of a frequency change than to its direction. Another experiment suggests that although the frequency-shift detectors cannot compare effectively two tones separated by an interfering tone, they are largely insensitive to interfering noise bursts. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
48.
Kwan Christine M. L.; Chun Kevin M.; Chesla Catherine A. 《Canadian Metallurgical Quarterly》2011,2(2):115
Practical knowledge on how to tailor research methods for Asian Americans is relatively scarce despite the rapid population growth of this ethnic group and the ongoing calls for greater cultural competence among researchers. Based on a 4-year qualitative study of family and cultural issues in diabetes management among Chinese American immigrants, this article presents data-based analyses of culturally nuanced group interview processes, and recommendations for conducting culturally appropriate group interviews. Group interview processes were prominently shaped by four cultural norms: sensitivity to social hierarchy, monitoring public display of strong emotions, face concerns, and emphasis on group harmony. Strategies for facilitating open and dynamic group interviews in the presence of these norms were identified. Skillful facilitation of group processes, either by accommodating or diffusing norms, was required to promote participant rapport and encourage disclosure of everyday experience. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
49.
S. Manoj Kumar N. Rajkumar W. Catherine Christinal Mary 《Wireless Personal Communications》2013,70(4):1697-1709
In Wireless Sensor Network (WSN) sensors are densely deployed where the intruders can compromise some sensor nodes and inject false data in order to raise false alarms, reduce network lifetime, utilize bandwidth resources and so on. False Data Injection can possibly occur in Data Aggregation (DA) and Data Forwarding (DF). This paper analyses EFDD Protocol-Early False Data Detection Protocol which addresses the two possibilities in a simple and secure way considering the constraints of sensor nodes. The main idea is the selection of the network structure; this protocol will work effectively in Spatial/Semantic Correlation Tree Structure (SCT). False Data Detection in DA is done using some monitoring nodes which will monitor the Data Aggregator. EFDD in SCT structure reduce the counterfeit data transmission when compared to other structure in a better way. The result shows that EFDD reduce data transmission by dropping false data earlier and it also reduces computation when compared to the existing schemes. 相似文献
50.
Catherine Le Corre-Guimard M’hamed Drissi Jacques Citerne Pierre Morillon 《电信纪事》1997,52(5-6):293-305
The high integration level associated to the increase of the operating frequency of microelectronic integrated circuits create complex electromagnetic coupling in the interconnection lines which lead to mismatch and frequency dispersion. In the present paper, we propose a full-wave analysis to characterise the electromagnetic behaviour of interconnection planar lines using mixed-potential integral equations technique. The theoretical and numerical treatments of Green’s functions for the specific structures are firstly presented. The calculated results for parallel and coplanar strips are compared to the published ones. The effect of the finite ground plane on the propagation constant and the characteristic impedance is then analysed for different permittivities. The obtained theoretical and experimental results for the reflection coefficient of straight resonators confirm finally the observed effect of the finite ground plane on the frequency dispersion and the scattering characteristics. 相似文献