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101.
In response to the growing need to provide the independent evaluation and examination of treatment programs, the Association for Advancement of Behavioral Therapy (AABT) formed the Professional Consultation and Peer Review Committee. The present study describes the peer review process in a hierarchical manner, beginning with the least demanding type of review or consultation and progressing to a full-scale evaluation. In the past 2 yrs, this committee has developed 6 types of review services that it offers free of charge to interested consumers and behavior therapists: individual case consultation between therapists, a compilation of guidelines for behavioral treatment programs, review of written materials of particular programs, on-site review of noncontroversial and controversial programs, and professional assistance in litigation involving determination of appropriate treatment. In all cases the committee promotes reliance on the empirical literature as the justification for treatment decisions and program operation. It is concluded that the review services are designed to protect individual clients and competent therapists and to assist in assuring appropriate treatment. (11 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
102.
103.
In Exp I, 2 territorial pairs of convict cichlid fish per aquarium were observed over 12 days. Aggressive behavior waned, but there was considerable between-days variability that was linked to progression from one stage in the parental cycle to the next (i.e., from no spawn to eggs, to larvae, and to free-swimming fry). The size of territory increased as one or the other pair progressed to the next stage. In Exp II, aggression in isolated pairs was studied during progression through the parental cycle, with a short daily presentation of a conspecific used as the stimulus. This procedure permitted study of changes in aggression unconfounded by the habituation that occurred in Exp I. It was predicted from Exp I that aggression would show increases at each stage transition. The predictions were supported. In Exp III, pairs were allowed to progress into the parental cycle in visual isolation from each other. When the pairs satisfied the requirements of being at different stages in the cycle, they were allowed visual access to each other. The pair with the more advanced spawn was initially more aggressive, but the aggressive behaviors did habituate. Results support the general tenets of P. M. Groves and R. F. Thompson's (see record 1971-02046-001) dual-process theory of habituation. (20 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
104.
High-spatial resolution mass spectrometric imaging of peptide and protein distributions on a surface
For the first time macromolecular ion microscope images have been recorded using matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS). Single-shot, mass-resolved images of the spatial distributions of intact peptide and protein ions over an area of 200 microm in diameter were obtained in less than 1 ms at a repetition rate of 12 Hz. The magnifying ion optics of the ion microscope allowed ion images to be obtained with a lateral resolution of 4 microm. These results prove the concept of high-resolution MALDI-MS imaging in microscope mode without the need for a tight laser focus and the accompanying sensitivity losses. The ion microscopy approach offers an improvement of several orders of magnitude in speed of acquisition compared to the conventional (microprobe) approach to MALDI-MS imaging. 相似文献
105.
The detection of a single-nucleotide mismatch in unlabeled duplex DNA by electrochemical methods is presented. Impedance spectroscopy is used to characterize a perfect duplex monolayer and three DNA monolayers differing in the position of the mismatch. The monolayers were studied as B-DNA (normal duplex DNA) and after conversion to M-DNA (a metalated duplex). Modeling of the impedance data to an equivalent circuit provides parameters that are useful in discriminating the four monolayer configurations. The resistance to charge transfer, R(CT), was lower for all duplexes after conversion to M-DNA. Contrary to expectations, R(CT) was also found to decrease for duplexes containing a mismatch. However, R(CT) was found to be diagnostic for mismatch detection. In particular, the difference in R(CT) between B- and M-DNA (deltaR(CT)) decreased from 190(22) omega.cm(2) for a perfectly matched duplex to 95(20), 30(20), and 85(20) omega.cm(2) for a mismatch at the top (distal), middle, and bottom (proximal) positions of the monolayer with respect to the gold surface. Further, a method to form loosely packed single-stranded (ss)-DNA monolayers by duplex dehybridization that is able to rehybridize to target strands is presented. Rehybridization efficiencies were in the range of 40-70%. Under incomplete hybridization conditions, the R(CT) was the same for matched and mismatched duplexes under B-DNA conditions. However, deltaR(CT) between B- and M-DNA, under incomplete hybridization, still provided a distinction. The deltaR(CT) for a perfect duplex was 76(12) omega.cm(2), whereas a mismatch in the middle of the sequence yielded a deltaR(CT) value of 30(15) omega.cm(2). The detection limit was measured and the impedance methodology reliably detected single DNA base pair mismatches at concentrations as low as 100 pM. 相似文献
106.
A laser spectrometer based on difference frequency generation (DFG) was deployed for real-time long-term monitoring of HCHO concentrations at an environmental monitoring site located at Deer Park, Texas, in the Greater Houston area. Three HCHO concentration measurements were made during the periods of July 20-31 (period I), August 2-14 (period II), and August 24-September 25 (period III), 2002. In periods I and II, differences in HCHO concentrations are apparent between day and night measurements, with elevated concentrations during daylight hours. Most of the HCHO peak values are less than 20 ppbV except for two intense peaks on August 02 (approximately 25 ppbV) and August 04 (approximately 30 ppbV). The formaldehyde concentration levels in ambient air at the measurement site are produced mainly by the photochemical oxidation of volatile organic compounds (VOCs) caused by intense sunlight during periods I and II. This observation was made based on a comparison with the ozone concentration, solar radiation, temperature, relative humidity, and wind speed data obtained from the Texas Commission on Environmental Quality (TCEQ). During period III, data collected by a time-integrating wet-chemical technique are compared to the data collected by the spectroscopic instrument. 相似文献
107.
108.
David B. Todd 《Polymer Engineering and Science》1975,15(6):437-443
Twin screw extruders are finding increased usage in reacting and devolatilizing applications. Using self-wiping profiles, the twin screws fulfill the requirement that there be no “dead” or “unmixed” zones. Agitator design must be chosen with care so that a reasonable balance can be obtained between forwarding rate, surface-generation rate, vapor passageway, power, and axial mixing. Techniques have been developed for measuring residence time distributions and characterizing axial flow behavior. The method also permits direct determination of the holdup in starved barrel applications. Data on residence time distribution are presented for 4-in. diameter twin screw equipment with a variety of rotor configurations. 相似文献
109.
PJ Hofschire EP Todd RL Varco EL Kaplan JE Edwards 《Canadian Metallurgical Quarterly》1976,69(3):439-440
We report an unusual case in which an apparently normal upper lobe of the right lung was supplied by major systemic arterial and pulmonary arterial vessels. The anomalous artery arose from the descending aorta. Following interruption of this vessel, the machinery-like murmur previously present disappeared. 相似文献
110.
Temperature dependence of the characteristic travel distance 总被引:1,自引:0,他引:1
The effect of temperature variation on the environmental fate of organic chemicals can be evaluated in steady-state multimedia box models by expressing chemical partitioning data and reaction rate coefficients as functions of temperature. Using such a modelthetemperature dependence of the characteristic travel distance in air L(A), which is a measure for the atmospheric long-range transport potential of organic chemicals, is calculated. Simulations are reported for a set of 40 chemicals of environmental interest. Increasing temperature is shown to have two opposing effects on L(A). Rates of chemical transformations in the atmosphere (k(air)) and surface media are increased, which reduces L(A). Rates of atmospheric deposition (k(dep)) are reduced leading to increased mobility and L(A). Accordingly, L(A) can monotonically increase or decrease with increasing temperature, or it can have a maximum in the modeled temperature range, but it cannot have a minimum. For chemicals with a strong temperature dependence of k(air) relative to k(dep), L(A) will increase with increasing temperature. Results for selected polychlorinated biphenyls are compared to monitoring data yielding qualitative agreement when chemical properties are adjusted to mean temperatures for the measurement period. The results demonstrate that the temperature dependence of the characteristic travel distance is highly dependent on chemical characteristics and can be counterintuitive. The use of mass balance models is thus essential. The difference between the L(A) values at 5 degrees C and 30 degrees C can be up to a factor of 6. Accordingly, chemical ranking with respect to L(A) can change significantly if performed at different temperatures. Implications of the different temperature dependencies on long-range transport to polar regions are discussed. 相似文献