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101.
The relatively flat lateral gain profile across a wide-strip laser diode does not allow sufficient overlap with the Gaussian fundamental mode of an external resonator to achieve saturation of the gain in the wings of the mode profile. Thus, parasitic free-running oscillation of the diode in an external-cavity laser is permitted by residual facet reflectivity of the antireflection-coated diode, and degrades the lateral-mode-selectivity of the external resonator at injection currents exceeding the threshold of the solitary diode. A relation between the maximum injection current at which the external-cavity laser will operate in a single mode and the diode's facet reflectivity is given  相似文献   
102.
Six undergraduate students participated in 2 experiments to determine whether the same mechanisms are activated during perception of real vs apparent motion. In Exp 1, Ss judged the quality of rigid motion between pairs of 3-dimensional drawings that differed by a rotation in depth. Rated quality of motion decreased with increasing angular disparity between the figures and with decreasing stimulus duration, regardless of whether the figures were vertical or oblique. In Exp 2, Ss participated in a mental rotation task using the same stimuli and angular disparities. Ss took longer to make decisions about obliquely aligned than vertically aligned stimuli. Results imply that perceived vs imagined movement through the same trajectory involves different processes. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
103.
This paper reports on ways of using digitised video from television cameras in user interfaces for computer systems. The DigitalDesk is built around an ordinary physical desk and can be used as such, but it has extra capabilities. A video camera mounted above the desk, pointing down at the work surface, is used to detect where the user is pointing and to read documents that are placed on the desk. A computer-driven projector is also mounted above the desk, allowing the system to project electronic objects onto the work surface and onto real paper documents. The animated paper documents project is considering particular applications of the technology in electronic publishing. The goal is to combine electronic and printed documents to give a richer presentation than that afforded by either separate medium. This paper describes the framework that has been developed to assist with the preparation and presentation of these mixed-media documents. The central component is a registry that associates physical locations on pieces of paper with actions. This is surrounded by a number of adaptors that assist with the creation of new documents either from scratch or by translating from conventional hypermedia, and also allow the documents to be edited. Finally the DigitalDesk itself identifies pieces of paper and animates them with the actions described in the registry.  相似文献   
104.
OBJECTIVE: To identify similarities and differences in neuropsychiatric correlates in children with Tourette's syndrome (TS) and those with ADHD. METHOD: The sample consisted of children with Tourette's syndrome with ADHD (N = 79), children with Tourette's syndrome without ADHD (N = 18), children with ADHD (N = 563), psychiatrically referred children (N = 212), and healthy controls (N = 140). RESULTS: Disorders specifically associated with Tourette's syndrome were obsessive compulsive disorder (OCD) and simple phobias. Rates of other disorders, including other disruptive behavioral, mood, and anxiety disorders, neuropsychologic correlates, and social and school functioning were indistinguishable in children with Tourette's and ADHD. However, children with Tourette's syndrome plus ADHD had more additional comorbid disorders overall and lower psychosocial function than children with ADHD. CONCLUSIONS: These findings confirm previously noted associations between Tourette's syndrome and OCD but suggest that disruptive behavioral, mood, and anxiety disorders as well as cognitive dysfunctions may be accounted for by comorbidity with ADHD. However, Tourette's syndrome plus ADHD appears to be a more severe condition than ADHD alone.  相似文献   
105.
BACKGROUND: So far only a few cases of carcinoma in situ of the fallopian tube have been reported, but its detailed clinical and pathologic findings, including cytology, have not been fully described. CASE: A 70-year-old female was admitted to our hospital because of irregular genital bleeding. Endometrial smear revealed a small number of atypical cells with a clear background. Hysterectomy, bilateral salpingo-oophorectomy and omentectomy were performed. Grossly, a grayish white papillary tumor, measuring 1.5 x 1.0 cm, was observed within the lumen of the left fallopian tube. Microscopically, the diagnosis of papillary adenocarcinoma in situ of the left fallopian tube was made according to 1992 International Federation of Gynecologists and Obstetricians fallopian tube staging. CONCLUSION: Although endometrial brush cytology is not sensitive enough to detect a primary carcinoma of the fallopian tube, our case indicates that it may contribute useful information on extrauterine diseases and can detect a stage 0 cancer of the fallopian tube. Clinicians, as well as pathologists, should consider the possibility of fallopian tube cancer if cervical or endometrial cytology shows atypical cells with papillary patterns with a clear background but endometrial curettage cannot prove malignancy.  相似文献   
106.
107.
Equilibrium dialysis and Scatchard plots were used to establish that human and rabbit paraoxonases both have two calcium binding sites. Independent-site and stepwise constant analyses were used to calculate a higher affinity site (Kd1) of 3.6 +/- 0.9 x 10(-7) M for human A paraoxonase, and 1.4 +/- 0.5 x 10(-8) M for rabbit paraoxonase, and a lower affinity site (Kd2) of 6.6 +/- 1.2 x 10(-6) M for human A paraoxonase, and 5.3 +/- 0.94 x 10(-6) M for rabbit paraoxonase. In both species, the higher affinity sites were found to be essential to maintain hydrolytic activity; complete removal of calcium led to irreversible inactivation. The lower affinity sites were required for catalytic activity, and their binding of calcium was reversible. Experimentally estimated values of Kd2 based on the concentration of calcium required to obtain half the maximum enzymatic activity were 3 microM for human A and B paraoxonases, and also in the order of 3 microM for rabbit paraoxonase, using three different substrates. Calcium was the only metal found that protects against denaturation and also confers hydrolytic activity with these two mammalian paraoxonases.  相似文献   
108.
This study investigated medical waste practices used by hospitals in Oregon, Washington, and Idaho, which includes the majority of hospitals in the U.S. Environmental Protection Agency's (EPA) Region 10. During the fall of 1993, 225 hospitals were surveyed with a response rate of 72.5%. The results reported here focus on infectious waste segregation practices, medical waste treatment and disposal practices, and the operating status of hospital incinerators in these three states. Hospitals were provided a definition of medical waste in the survey, but were queried about how they define infectious waste. The results implied that there was no consensus about which agency or organization's definition of infectious waste should be used in their waste management programs. Confusion around the definition of infectious waste may also have contributed to the finding that almost half of the hospitals are not segregating infectious waste from other medical waste. The most frequently used practice of treating and disposing of medical waste was the use of private haulers that transport medical waste to treatment facilities (61.5%). The next most frequently reported techniques were pouring into municipal sewage (46.6%), depositing in landfills (41.6%), and autoclaving (32.3%). Other methods adopted by hospitals included Electro-Thermal-Deactivation (ETD), hydropulping, microwaving, and grinding before pouring into the municipal sewer. Hospitals were asked to identify all methods they used in the treatment and disposal of medical waste. Percentages, therefore, add up to greater than 100% because the majority chose more than one method. Hospitals in Oregon and Washington used microwaving and ETD methods to treat medical waste, while those in Idaho did not. No hospitals in any of the states reported using irradiation as a treatment technique. Most hospitals in Oregon and Washington no longer operate their incinerators due to more stringent regulations regarding air pollution emissions. Hospitals in Idaho, however, were still operating incinerators in the absence of state regulations specific to these types of facilities.  相似文献   
109.
A diffusion cell with an artificial membrane and the single-pass perfused rabbit ear were used to evaluate the percutaneous absorption of clonazepam from various 2-hydroxyethyl acetate (HEA) patches. The influence on drug permeation of the various type of enhancers (isopropylmyristate, lauryl alcohol, propylene glycol and water) in the patches was tested. A comparison between the two types of systems of percutaneous absorption of clonazepam has been done. The results showed that HEA patches produce controlled uniform drug release, modulated by the addition of enhancers.  相似文献   
110.
Circadian clocks are complex biochemical systems that cycle with a period of approximately 24 hours. They integrate temporal information regarding phasing of the solar cycle, and adjust their phase so as to synchronize an organism's internal state to the local environmental day and night. Nocturnal light is the dominant regulator of this entrainment. In mammals, information about nocturnal light is transmitted by glutamate released from retinal projections to the circadian clock in the suprachiasmatic nucleus of the hypothalamus. Clock resetting requires the activation of ionotropic glutamate receptors, which mediate Ca2+ influx. The response induced by such activation depends on the clock's temporal state: during early night it delays the clock phase, whereas in late night the clock phase is advanced. To investigate this differential response, we sought signalling elements that contribute solely to phase delay. We analysed intracellular calcium-channel ryanodine receptors, which mediate coupled Ca2+ signalling. Depletion of intracellular Ca2+ stores during early night blocked the effects of glutamate. Activators of ryanodine receptors induced phase resetting only in early night; inhibitors selectively blocked delays induced by light and glutamate. These findings implicate the release of intracellular Ca2+ through ryanodine receptors in the light-induced phase delay of the circadian clock restricted to the early night.  相似文献   
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