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1.
Experimental tests showed that poststrike elevation in tongue-flicking rate (PETF) and strike-induced chemosensory searching (SICS) in the gila monster last longer than reported for any other lizard. Based on analysis of numbers of tongue-flicks emitted in 5-min intervals, significant PETF was detected in all intervals up to and including minutes 41–45. Using 10-min intervals, PETF lasted though minutes 46–55. Two of eight individuals continued tongue-flicking throughout the 60 min after biting prey, whereas all individuals ceased tongue-flicking in a control condition after minute 35. The apparent presence of PETF lasting at least an hour in some individuals suggests that there may be important individual differences in duration of PETF. PETF and/or SICS are present in all families of autarchoglossan lizards studied except Cordylidae, the only family lacking linguallly mediated prey chemical discrimination. However, its duration is known to be greater than 2-min only in Helodermatidae and Varanidae, the living representatives of Varanoidea. That prolonged PETF and SICS are typical of snakes provides another character supporting a possible a varanoid ancestry for Serpentes. Analysis of 1-min intervals showed that PETF occurred in the first minute. A review of the literature suggests that a pause in tongue-flicking and delay of searching movements are absent in lizards and the few nonvenomous colubrid snakes tested. The delayed onset of SICS may be a specific adaptation of some viperid snakes to allow potentially dangerous prey to be rendered harmless by venom following voluntary release after envenomation and preceding further physical contact with the prey.  相似文献   
2.
Adany P  Arnett DC  Johnson CK  Hui R 《Applied physics letters》2011,99(18):181112-1811123
We demonstrate a wavelength tunable optical excitation source for coherent Raman scattering (CRS) spectroscopy based on a single femtosecond fiber laser. Electrically controlled wavelength tuning of Stokes optical pulses was achieved with soliton self frequency shift in an optical fiber, and linear frequency chirping was applied to both the pump and the Stokes waves to significantly improve the spectral resolution. The coherent anti-Stokes Raman scattering (CARS) spectrum of cyclohexane was measured and vibrational resonant Raman peaks separated by 70?cm(-1) were clearly resolved. Single laser-based tunable excitation may greatly simplify CRS measurements and extend the practicality of CRS microscopy.  相似文献   
3.
    
This article describes the Medical Expenditure Panel Survey (MEPS), the third in a series of nationally representative surveys of medical care use and expenditures sponsored by the Agency for Health Care Policy and Research. The MEPS is designed to provide extensive data on the types of health care services American use, how frequently they use them, how much is paid for the services, and who pays for them. It also will provide information on the types and costs of private health insurance available to the U.S. population. The survey is unparalleled in its degree of detail, as well as its ability to link medical care use, payments, and health insurance coverage to specific survey respondents and their families. It allows analysts to examine how individual and family characteristics, including the characteristics of their health insurance, affect medical care use and spending. This article discusses each of the MEPS components, focusing on design enhancements that have been made since the survey was last conducted nearly a decade ago.  相似文献   
4.
OBJECTIVE—To evaluate adolescents'' responses to cigarette advertisements for different brands.DESIGN—Adolescents were shown one print advertisement for each of five cigarette brands (Camel, Marlboro, Kool, Benson & Hedges, and Lucky Strike). They indicated on a structured questionnaire how many times they had seen the advertisement (or one almost like it), how much they liked it, whether or not they thought it made smoking more appealing, and whether or not it made them want to smoke cigarettes of that brand.SETTING—Middle school and high school classrooms, seven schools in four states in the United States (New York, Pennsylvania, Ohio, and Texas). The classrooms were selected randomly within each school.PARTICIPANTS—534 adolescents in grades 6-12 (ages 11-18 years) from seven schools in four states, 54% female, 76% white.RESULTS—The advertisements for Camel and Marlboro were more likely than the advertisements for the other brands to be seen, to be liked, to be viewed as making smoking appealing, and to influence adolescents to want to smoke cigarettes of that brand. More than 95% of the adolescents had seen an advertisement featuring Joe Camel or the Marlboro Man at least once, and more than 50% had seen these advertisements six or more times. Nearly half believed that the Joe Camel advertisement makes smoking more appealing, and 40% believed that the Marlboro Man advertisement makes smoking more appealing. Adolescent smokers were more likely than non-smokers to believe that the advertisements for Camel and Marlboro make smoking more appealing.CONCLUSIONS—The advertisements most popular among adolescents are for two of the brands they are most likely to smoke—Marlboro and Camel. The results of the study are consistent with the view that certain cigarette advertisements enhance the appeal of smoking to many adolescents.  相似文献   
5.
The construction, modeling, and performance characteristics of a new resonator design for ultrafast cavity-dumped oscillators are presented. An acousto-optic Bragg cell was incorporated at the end of the longer arm of a Ti:sapphire oscillator rather than in the shorter arm as in several recent studies. The new arrangement improves the pulse intensity stability of the oscillator and significantly reduces the effort required in construction. The experimental findings are supported by comparison of the stability regions of the laser cavities based on the two different designs. To demonstrate the potential of cavity-dumped oscillators for spatially resolved ultrafast spectroscopy studies, the pulse duration is characterized at the focal plane of two achromatic high-N.A. oil-immersion objectives with different amounts of flat-field correction. Transform-limited pulse widths as short as 15 fs are obtained. To our knowledge, this is the shortest pulse duration measured with true high-N.A. (N.A. > 1) focusing conditions.  相似文献   
6.
OBJECTIVE: To provide a single source for the best available estimates of the national prevalence of arthritis in general and of selected musculoskeletal disorders (osteoarthritis, rheumatoid arthritis, juvenile rheumatoid arthritis, the spondylarthropathies, systemic lupus erythematosus, scleroderma, polymyalgia rheumatica/giant cell arteritis, gout, fibromyalgia, and low back pain). METHODS: The National Arthritis Data Workgroup reviewed data from available surveys, such as the National Health and Nutrition Examination Survey series. For overall national estimates, we used surveys based on representative samples. Because data based on national population samples are unavailable for most specific musculoskeletal conditions, we derived data from various smaller survey samples from defined populations. Prevalence estimates from these surveys were linked to 1990 US Bureau of the Census population data to calculate national estimates. We also estimated the expected frequency of arthritis in the year 2020. RESULTS: Current national estimates are provided, with important caveats regarding their interpretation, for self-reported arthritis and selected conditions. An estimated 15% (40 million) of Americans had some form of arthritis in 1995. By the year 2020, an estimated 18.2% (59.4 million) will be affected. CONCLUSION: Given the limitations of the data on which they are based, this report provides the best available prevalence estimates for arthritis and other rheumatic conditions overall, and for selected musculoskeletal disorders, in the US population.  相似文献   
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8.
A progressive fibrous myopathy may result from chronic intramuscular drug abuse. This complication may mimic other rheumatic disorders and early recognition may prevent disability. The patient described here presented with fixed flexion and extension contracture of hips and knees, respectively, after abusing meperidine and other agents for 3 years. Soft tissues of thighs and buttocks were "wood hard," EMG showed absence of action potentials in affected muscles, and biopsy revealed extensive replacement of muscle with dense, acellular fibrous tissue. Possible mechanisms are discussed.  相似文献   
9.
Examined Canadian hospital psychology in terms of the existing organizational models, professional practices, academic activities, and professional orientations of hospital psychologists in a survey of 340 hospitals. Results reveal that psychologists were active clinically and academically in Canadian hospitals in a wide variety of health care areas in addition to traditional mental health areas. In the majority of hospitals, psychologists were organized in independent departments of psychology or behavioral science, although physician influence appeared to be a strong factor in practice. Medical staff membership and academic appointments for hospital psychologists were relatively low. Recommendations for the future development of hospital psychology in Canada are outlined. (French abstract) (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
10.
Responds to the comments by L. T. Hoshmand (see record 2003-08988-012) and J. Aros (see record 2003-08988-013) on the article by J. Arnett (see record 2002-18352-003) regarding the psychology of globalization. In this response, Arnett discusses the moral implications of globalization. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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