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91.
Young adult and aged F344 rats were compared on a silent gap variant of the prepulse inhibition paradigm. Animals were tested using a 50-ms single tone cue, followed by 8 days of silent gap testing. The first 3 days of gap testing were long gaps (range 2 to 100 ms) followed by 5 days of short gaps (range 2 to 10 ms). The effects of gap length, prior experience, and age, on the magnitude and direction (facilitation vs. attenuation) of the acoustic startle response, were examined. The young rats showed stronger and more reliable acoustic startle responses (uncued trials) during all acoustic startle tasks as compared to the old. The younger animals also exhibited a more consistent attenuated response across cues and days. Depending on silent gap length, both reduction (inhibition) and enhancement (facilitation) of startle were observed. Finally, only the young adult animals showed an experience-related shift from facilitation to attenuation in response to very short silent gap cues, and this initial early facilitation predicted later attenuation following additional experience. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
92.
Chemical communication plays many key roles in mammalian reproduction, although attention has focused particularly on male scent signalling. Here, we review evidence that female chemical signals also play important roles in sexual attraction, in mediating reproductive competition and cooperation between females, and in maternal care, all central to female reproductive success. Female odours function not only to advertise sexual receptivity and location, they can also have important physiological priming effects on male development and sperm production. However, the extent to which female scents are used to assess the quality of females as potential mates has received little attention. Female investment in scent signalling is strongly influenced by the social structure and breeding system of the species. Although investment is typically male-biased, high competition between females can lead to a reversed pattern of female- biased investment. As among males, scent marking and counter-marking are often used to advertise territory defence and high social rank. Female odours have been implicated in the reproductive suppression of young or subordinate females across a range of social systems, with females of lower competitive ability potentially benefiting by delaying reproduction until conditions are more favourable. Further, the ability to recognise individuals, group members and kin through scent underpins group cohesion and cooperation in many social species, as well as playing an important role in mother-offspring recognition. However, despite the diversity of female scent signals, chemical communication in female mammals remains relatively understudied and poorly understood. We highlight several key areas of future research that are worthy of further investigation. 相似文献
93.
With over thirty million individuals with disabilities being reported in the United States, and with information systems permeating
nearly every aspect of society, there is a growing urgency to ensure that everyone has equal access to technology. To render
information technologies universally accessible, researchers must have at their disposal an accurate and reliable user model.
Through the use of the conceptual framework presented here, accurate assumptions can be generated from knowledge of an individual’s
impairments, and functional abilities to influence the creation of a user profile. Ultimately, user profiles serve as a vital
attribute of user models applied to the design of technology in an effort to achieve universal access.
Published online: 18 May 2001 相似文献
94.
Controlled transportation of air‐ and electrochemically stable materials is of interest in many areas of science. Herein, we report the synthesis and characterization of an ionic liquid monomer and its corresponding polyelectrolyte. The translational movement of these ionic liquid droplets across a substrate using the mechanism of electrowetting on a dielectric (EWOD) is demonstrated with emphasis given to electrode design and selective switching in the device construction. Directional control of a 2 mm sized polyelectrolyte droplet is shown to laterally move across the substrate surface on the order of 10s of minutes due to its increased viscosity, whereas its ionic liquid monomer also transverses but at a much faster pace‐on the order of 10s of seconds. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
95.
96.
Naomi H. Bennett Holly R. Chinnery Laura E. Downie Lisa J. Hill Liam M. Grover 《Advanced functional materials》2020,30(14)
Eye drops are the most common and inexpensive approach to topical ocular drug delivery. Eye drops offer a noninvasive treatment strategy; however, this can be detrimental to therapeutic efficacy when compared to invasive methods such as surgeries, implants, and injections. Improvements to the efficacy of the topical delivery of drugs to ocular tissues are currently being explored and much of this work centers on adjusting the formulation of the eye drops and prolonging the bioavailability of the therapeutic agent. This is often in preference to improving other patient‐focused or clinical factors. In this progress report, conventional, commercially available polymer eye drops are explored and the ability for current and future innovations to maintain the existing benefits of eye drops to the patient is assessed. The final materials and form of the drops (liquid, gel, or other) and the immunological implications for the user are explored. There is currently no consensus for how to most effectively improve the ocular retention and drug delivery capabilities of eye drops, but key issues are highlighted in the context of current methods under development, and potential questions and considerations for future innovations are raised. 相似文献
97.
Niobium Doping and Dielectric Anomalies in Bismuth Titanate 总被引:4,自引:1,他引:3
Holly S. Shulman Dragan Damjanovic Nava Setter 《Journal of the American Ceramic Society》2000,83(3):528-532
A study of the complex permittivity in bismuth titanate was conducted to reveal the nature of an anomaly in the real part of the permittivity, which occurs below the Curie temperature. This anomaly is frequency dependent and is caused by a combination of two relaxation phenomena that appear in the imaginary part of the permittivity. One of the relaxations showed classic characteristics of an ion-jump process. Niobium doping suppressed this relaxation and eliminated the nonferroelectric anomaly in permittivity. Niobium is proposed to affect the ion-jump relaxation through a decrease in the concentration and possibly the mobility of oxygen vacancies. 相似文献
98.
Frank Ellen; Swartz Holly A.; Mallinger Alan G.; Thase Michael E.; Weaver Elizabeth V.; Kupfer David J. 《Canadian Metallurgical Quarterly》1999,108(4):579
In a randomized, controlled trial, the authors studied an adjunctive, individual psychotherapy, interpersonal and social rhythm therapy (IPSRT) for bipolar disorder. After stabilizing participants with episode appropriate pharmacotherapy and either IPSRT or intensive clinical management (CM), participants were reassigned to IPSRT or CM in conjunction with pharmacotherapy for 2 years of preventative treatment. Early results (n?=?82) suggest that altering participants' treatment assignment at entry to the preventative phase is related to risk of recurrence. Participants remaining in the same treatment for both acute and preventative phases had lower rates of recurrence (40%) and levels of symptomatology over the subsequent 52 weeks than those reassigned to the alternate modality. This finding, consistent with the authors' philosophy that bipolar patients benefit from stable routines, suggests that disruptions in the psychosocial treatment plan contribute to worse outcomes. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
99.
Holly Tuokko Anita Myers Alexandra Jouk Shawn Marshall Malcolm Man-Son-Hing Michelle M. Porter Michel Bédard Isabelle Gélinas Nicol Korner-Bitensky Barbara Mazer Gary Naglie Mark Rapoport Brenda Vrkljan 《Accident; analysis and prevention》2013
The relations among driving-related psychosocial measures (e.g., driving comfort, attitudes toward driving) and measures of self-reported health were examined in the context of driver characteristics (i.e., age and gender) within the Canadian Driving Research Initiative for Vehicular Safety in the Elderly (Candrive II) baseline data, available for the cohort of 928 drivers, 70 years of age and older. Older members of the cohort had lower comfort scores and poorer perceptions of their driving abilities. Men reported significantly higher levels of driving comfort than women. When analyses including health were controlled for age and gender, significant relations with health status were evident for most of the psychosocial measures. These findings extend previous research and suggest that attitudes, beliefs, and perceptions about driving may be influenced by health status and act as mediators in the self-regulation process. 相似文献
100.