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21.
We present the thesis that the psychology internship and the university-affiliated practicum site offer a special opportunity to train new professionals in brief psychotherapy. The reasons for this include (a) a growing client demand for time-limited treatment and hence psychology's responsibility to prepare professionals in this mode of intervention, (b) a period of residence that can be comfortably tailored to training in short-term psychotherapy, and (c) trainees who are eager to learn a pragmatic form of intervention. Training considerations are outlined and include client selection variables, therapist/trainee considerations, and supervision/teaching. Conclusions are offered and emphasize the agency's and supervisors' need to feel a commitment to train in this modality. Likewise, the program should seek trainees who are eager to learn brief psychotherapy. In order to maximize the opportunity for a successful experience, careful consideration should be given to client selection criteria. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
22.
Twenty three patients with paediatric soft tissue sarcomas who had relapsed or refractory disease were treated with a rapid schedule of intravenous etoposide (100 mg/m2 daily on three consecutive days, weekly over 3 weeks). The regimen was well tolerated with predictable myelotoxicity. In 19 patients with rhabdomyosarcoma, there was a response rate of 42%. This appears to be better than previously reported with conventional three weekly schedules. These data indicate that for rhabdomyosarcoma, as for some other tumours, a divided dose regimen may be the optimal schedule and is worthy of further evaluation.  相似文献   
23.
To date only gas-atomised tool steel powders have been used for direct laser additive manufacturing and the potential benefits of using water-atomised powders have not been explored. As the use of the process in the rapid tooling field is growing, there is a need to explore if the less expensive water-atomised materials can be realistically utilised. A comparative investigation is described, using gas- and water-atomised H13 powder deposited with a CO2 laser and coaxial powder feed nozzle. Multiple layer wall dimensions, composition, microstructure, surface finish and hardness are related to process conditions and the causes of the observed phenomena are discussed. An energy-balance method is used to model the temperature of the powders and the results used to explain some of the effects. Results indicate that using the lower cost water-atomised powder still allows a metallurgically sound component to be built and does not significantly affect surface finish. The build rate is, however, lower and the water-atomised powder tends to produce slightly softer walls, attributable to a higher temperature during tempering of deposited material by subsequent laser passes.  相似文献   
24.
25.
A novel design for a dry-aerosol generator that efficiently produces a well-dispersed dust suspension using small quantities of a PM2.5-enriched powder sample is described. The motivation to develop a highly efficient dry-aerosol particle generator was to facilitate collaborative projects that combine in vitro cell culture experiments and multiday inhalation exposures using a single batch of well-characterized particles. Premixing of the test particles with larger diameter glass beads permits delivery of aerosol concentrations from 100–1000 μ g/m3 to an exposure chamber using only milligram quantities of the test powder per hour. Examination of exposure chamber filter samples by scanning electron microscopy showed well-dispersed particles of the test powder free of glass spheres or fragments. Data are presented from experiments using coal fly ash as the test powder to illustrate the system performance.  相似文献   
26.
The use of porous surface structures is gaining popularity in biomedical implant manufacture due to its ability to promote increased osseointegration and cell proliferation. Laser direct metal deposition (LDMD) is a rapid manufacturing technique capable of producing such a structure. In this work LDMD with a diode laser in continuous mode and with a CO2 laser in pulsed modes are used to produce multi-layer porous structures. Gas-atomized Ti-6Al-4V and 316L stainless steel powders are used as the deposition material. The porous structures are compared with respect to their internal geometry, pore size, and part density using a range of techniques including micro-tomography. Results show that the two methods produce radically different internal structures, but in both cases a range of part densities can be produced by varying process parameters such as laser power and powder mass flow rate. Prudent selection of these parameters allows the interconnected pores that are considered most suitable for promoting osseointegration to be obtained. Analytical models of the processes are also developed by using Wolfram Mathematica software to solve interacting, transient heat, temperature and mass flow models. Measured and modelled results are compared and show good agreement.  相似文献   
27.
A high speed lead plating process has been developed. The bath contains, per gal US, Pb(BF4)2 62·5 oz, HBF4 and H2BO2 ach 6 oz and hydroquinone 1·3 oz. The optimum temperature is 160°F and cathode surface velocities of 0–150 ft/min have been evaluated. Limiting current densities up to 3100 A/ft2 and average operating current densities up to 1000 A/ft2 are possible. Deposits are fine grained and cover basis metal defects even with coatings 0·1 mil or less. Brushing the basis metal and especially interrupting the lead deposition to brush the deposit reduces porosity. Coatings 0·05 to 0·1 mil thick so produced on steel when tested resisted corrosion by shellac better than terne and tinplate and were satisfactory in water-base paints. However, lead coatings on steel have poor solderability. Salt spray tests confirm the superiority of the deposits produced from the hydroquinone bath with or without brushing treatments. Copper and tin strikes were of no value in corrosion or solderability tests. Power and metal cost is lower for the lead coatings than for zinc coatings of equal thickness. Production facilities for lead-plating steel strip of various gauges are discussed.  相似文献   
28.
One hundred and thirty-four adults and 204 children were randomized in two prospective, parallel comparative multicentre trials to receive either conventional amphotericin B 1 mg/kg/d (c-AMB), liposomal amphotericin B 1 mg/kg/d(L-AMB1) or liposomal amphotericin B 3 mg/ kg/d (L-AMB3). Patients were entered if they had a pyrexia of unknown origin (PUO) defined as temperature of 38 degrees C or more, not responding to 96 h of systemic broad-spectrum antibiotic treatment, and neutropenia (< 0.5 x 10(9)/l). The safety and toxicity of liposomal amphotericin B was compared with that of conventional amphotericin B. Efficacy of treatment was assessed, with success defined as resolution of fever for 3 consecutive days (< 38 degrees C) without the development of any new fungal infection. Clinical and laboratory parameters were collected for safety analysis. In both the paediatric and adult populations, L-AMB treated patients had a 2-6-fold decrease in the incidence (P < or = 0.01) of test-drug-related side-effects, compared to c-AMB. Severe trial-drug-related side-effects were seen in 1% of L-AMB treated patients, in contrast to 12% of patients on c-AMB (P < 0.01). Nephrotoxicity, in the patient subset not receiving concomitant nephrotoxic agents, defined as a doubling from the patients baseline serum creatinine level, was not observed in the L-AMB1 arm whereas the incidence was 3% in patients on L-AMB3 and 23% in those on c-AMB (P < 0.01). Moreover, time to develop nephrotoxicity was longer in both L-AMB arms than c-AMB (P < 0.01). Severe hypokalaemia was observed less frequently in both L-AMB arms (P < 0.01). Analysis was by intention-to-treat and included all patients randomized. Success was defined by a minimum of 3 consecutive days with fever (< 38 degrees C) continuing to study end indicated by recovery of neutrophils to 0.5 x 10(9)/l. Addition of systemic antifungal therapy or development of systemic fungal infection were failures as was persistent fever to study end. Efficacy assessments indicated success in 49% of the total group treated with c-AMB, 58% of patients responded to L-AMB1 and 64% to L-AMB3. A statistically significant difference was found between c-AMB and L-AMB3 (P = 0.03) but a Kaplan-Meier analysis of time to differvescence of fever showed there was no significant difference between the arms. It was concluded that liposomal amphotericin at either 1 or 3 mg/kg/d was significantly safer than conventional amphotericin B in children and adults. The main aim of this open-label study was to compare safety between the three trial arms. However, we provide evidence for an equivalent or possibly superior efficacy of liposomal amphotericin with regard to resolution of fever of unknown origin. Subsequent trials should compare amphotericin preparations in defined fungal infections.  相似文献   
29.
This study intercompared the performance of eight band-ratio chlorophyll-a algorithms which together can be used to process measurements from the ocean colour satellite sensors CZCS, OCTS, SeaWiFS, MODIS, MERIS, and GLI. The study area included Subtropical, Subtropical Front and Subantarctic waters east of New Zealand, and Case 1 waters of the New Zealand northeast continental shelf. Over 170 co-incident measurements of spectral normalised water-leaving radiance and near-surface concentration of chlorophyll-a were made on nine research voyages between 1998 and 2000. The studentised bootstrap method was used to identify statistically significant bias in algorithm products relative to in situ measurements. The band-ratio algorithms used by CZCS, OCTS and SeaWiFS missions systematically underestimated chlorophyll-a concentration in the offshore regions by between 21% and 45%, but showed no systematic bias in the continental shelf waters. The band-ratio algorithms applicable to the MODIS and MERIS sensors had no clear bias with respect to in situ measurements in offshore waters, but had a positive bias of 20% over the continental shelf. The proposed GLI band-ratio algorithm led to estimates that were negatively biased with respect to in situ measurement offshore (− 30%), and positively biased over the continental shelf (20%). The results were consistent with unusually high values of absorption in the blue part of the spectrum (443-490 nm) compared to the green part (∼ 550 nm) by phytoplankton pigments in the offshore waters, and high chlorophyll-specific absorption over the continental shelf.  相似文献   
30.
OBJECTIVES: The authors evaluated the cost-effectiveness of a community-level HIV prevention intervention that used peer leaders to endorse risk reduction among gay men. METHODS: A mathematical model of HIV transmission was used to translate reported changes in sexual behavior into an estimate of the number of HIV infections averted. RESULTS: The intervention cost $17,150, or about $65,000 per infection averted, and was therefore cost-saving, even under very conservative modeling assumptions. CONCLUSIONS: For this intervention, the cost of HIV prevention was more than offset by savings in averted future medical care costs. Community-level interventions to prevent HIV transmission that use existing social networks can be highly cost-effective.  相似文献   
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