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71.
An annular laser beam based powder cladding head, which enables an axial powder feeding and variation of the laser beam intensity distribution (LBID) on the workpiece surface is presented. The influence of typical LBIDs, including Ring, Tophat(?), Tophat(+), and Gaussian-like, on a cladding process has been characterized based on the process and melt pool visualization, powder catchment efficiency, clad layer geometry, and porosity. The results showed that the most stable process without plasma formation but with low dilution and porosity of the clad layer can be achieved within the range from a Ring to a Tophat(?) LBID. Additionally, axial powder feeding results in a high powder catchment efficiency above 80%.  相似文献   
72.
Hybrid magnetic nanostructures with high coercivity have immense application potential in various fields. Nickel (Ni) electrodeposited inside Cobalt (Co) nanotubes (a new system named Ni @ Co nanorods) were fabricated using a two-step potentiostatic electrodeposition method. Ni @ Co nanorods were crystalline, and they have an average diameter of 150 nm and length of ~15 μm. The X-ray diffraction studies revealed the existence of two separate phases corresponding to Ni and Co. Ni @ Co nanorods exhibited a very high longitudinal coercivity. The general mobility-assisted growth mechanism proposed for the growth of one-dimensional nanostructures inside nano porous alumina during potentiostatic electrodeposition is found to be valid in this case too.  相似文献   
73.
Emerging pharmacogenetics research may improve clinical outcomes for common complex conditions typically treated in primary care settings. Physicians' willingness to offer genetically-tailored treatments to their patients will be critical to realizing this potential. According to recent research, it is likely that genotypes used to tailor smoking will have pleiotropic associations with other addictions and diseases, and may have different frequencies across populations. These additional features may pose an additional barrier to adoption. To assess physicians' willingness to offer a new test to individually tailor smoking treatment according to specific test characteristics, we conducted a national mailed survey of 2,000 U.S. primary care physicians (response rate: 62.3%). Physicians responded to a baseline scenario describing a new test to tailor smoking treatment, and three additional scenarios describing specific test characteristics based on published research; there was random assignment to one of two survey conditions in which the test was described as a genetic or non-genetic test. Our findings indicate physicians' self-reported likelihood (0-100 scale) that they would offer a new test to tailor smoking cessation treatment ranged from 69%-78% across all scenarios. Relative to baseline scenario responses, physicians were significantly less likely to offer the test when informed that the same genotypes assessed for treatment tailoring: (1) may also identify individuals predisposed to become addicted to nicotine (p<.001), (2) differ in frequency by race (p<.004), and (3) may have associations with other conditions (e.g., alcohol and cocaine addiction, attention deficit hyperactivity disorder ADHD and Tourette Syndrome) (p<.01). Describing a new test to individually tailor smoking treatment as a "genetic" versus non-genetic test significantly reduced physicians' likelihood of offering the test across all scenarios, regardless of specific test characteristics (p<.0007). Effective education of primary care physicians will be critical to successful integration of promising new pharmacogenetic treatment strategies for smoking.  相似文献   
74.
Although related to inflammatory markers in adults, little is known about the association between cigarette smoking and C-reactive protein (CRP) in adolescent smokers. We examined the association between high-sensitivity CRP (hs-CRP) concentrations and smoking in youth. We used data from a cross-sectional, province-wide survey of a representative sample of youth conducted in Quebec, Canada, in 1999. Data were collected in self-report questionnaires completed by participants and their parents. Participants provided a fasting blood sample, and anthropometric measures were undertaken by trained technicians. The present analysis pertains to 1,501 adolescents aged 13 and 16 years who completed questionnaires and for whom blood samples were available. The independent association between a six-category indicator of smoking status and elevated hs-CRP, defined as a value at least in the 90th percentile of the age- and sex-specific CRP distribution, was assessed in multiple logistic regression analyses controlling for potential confounders. Relative to never-smokers, the odds ratios (95% confidence intervals) for puffers (i.e., never smoked a whole cigarette), those who smoked but not in the past month, light past-month smokers, moderate past-month smokers, and heavy past-month smokers were 1.04 (0.55-1.98), 1.76 (1.06-2.94), 1.39 (0.70-2.76), 2.07 (0.96-4.42), and 2.40 (1.18-4.88), respectively. Our data suggest a positive association between smoking status and elevated CRP in adolescents, and in particular among heavier past-month smokers. Damage related to cigarette smoking may begin soon after tobacco use initiation, reinforcing the preventive message that no level of smoking is safe in youth.  相似文献   
75.
ABSTRACT

Recovery of organic material from Israeli Mishor Rotem oil shale with toluene under supercritical conditions was investigated. The rate of solubilization, change of structural aspects and molecular weights of solubilized products with time were investigated. Experiments to recover organic material from shale were performed in a stainless steel high pressure autoclave. Shale Sample was charged in a sintered glass crucible suspended from the cap of the autoclave; toluene was the solvent in all experiments. Solvent/shale ratio was 20; experimental temperature was 34O°C. The gaseous products were analyzed by gas chromatography. Molecular weights of the organic material recovered was measured by gel permeation chromatography technique. FTIR spectra of the organic material recovered and fractions isolated by extractive and chromatographical methods were measured. The amount of kerogen remaining in the spent shale was determined by oxidative derivative thermal gravimetry. A steady state in the production of solubles was reached within 60 minutes at 340°C with a yield of 60 percent. After this time no further amounts of organic material was recovered. The molecular weights of the recovered organic material decreased at extended times after the steady state was reached. It appeared that the structure of the organic material recovered remained unchanged until the steady state condition is reached whereupon some structural changes occurred. At extended times the organic material was converted into more aromatic and less hydroxyl containing structures of lower molecular weight. The organic material recovered upon reaching steady state was fractionated into 63 percent oils (pentane solubles) and 32 percent asphaltenes (toluene solubles). The oile contained aliphatics and monoaromatic structures and the asphaltenes contained polyaromatic polar structures. Gases which constituted 4 percent of the initial kerogen were produced during the heating period to 340°C. The amount of carbon monoxide produced remained constant and amounts of hydrogen, carbon dioxide and methane decreased after supercritical conditions were attained.  相似文献   
76.
The aim of this study was to explore the long-term effects of affect-focused body psychotherapy (ABP) for patients with generalized anxiety disorder (GAD). A group of 61 consecutive patients, 21–55 years old, were randomized to ABP and psychiatric treatment as usual (TAU). The patients were assessed before treatment and followed up 1 and 2 years after inclusion. The ABP patients received one session of treatment per week during 1 year. Three self-report questionnaires were administered; Symptom Checklist—90, Beck Anxiety Inventory, and the WHO (Ten) Well-Being Index. In both groups, there was a significant improvement. On termination, the ABP group had improved significantly more on the SCL-90 Global Symptom Index than the TAU group, whereas the differences were short of significance on the other two scales. The integration of bodily techniques with a focus on affects in a psychodynamically informed treatment seems to be a viable treatment alternative for patients with GAD. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
77.
This reply to the commentary by E. Staub and L. A. Pearlman (2009) revisits the field experimental results of E. L. Paluck (2009). It introduces further evidence and theoretical elaboration supporting Paluck's conclusion that exposure to a reconciliation-themed radio soap opera changed perceptions of social norms and behaviors, not beliefs. Experimental and longitudinal survey evidence reinforces the finding that the radio program affected socially shared perceptions of typical or prescribed behavior—that is, social norms. Specifically, measurements of perceptions of social norms called into question by Staub and Pearlman are shown to correlate with perceptions of public opinion and public, not private, behaviors. Although measurement issues and the mechanisms of the radio program's influence merit further testing, theory and evidence point to social interactions and emotional engagement, not individual education, as the likely mechanisms of change. The present exchange makes salient what is at stake in this debate: a model of change based on learning and personal beliefs versus a model based on group influence and social norms. These theoretical models recommend very different strategies for prejudice and conflict reduction. Future field experiments should attempt to adjudicate between these models by testing relevant policies in real-world settings. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
78.
Interim, centralized, engineered (dry cask) storage facilities for USA light water power reactor spent nuclear fuel (SNF) should be implemented to complement and to offer much needed flexibility while the Nuclear Regulatory Commission is funded to complete its evaluation of the Yucca Mountain License and to subject it to public hearings. The interim sites should use the credo reproduced in Table 1 [Bunn, M., 2001. Interim Storage of Spent Nuclear Fuel. Harvard University and University of Tokyo] and involve both the industry and government. The sites will help settle the 50 pending lawsuits against the government and the $11 billion of potential additional liabilities for SNF delay damages if Yucca Mountain does not being operation in 2020 [DOE, 2008a. Report to Congress on the Demonstration of the Interim Storage of Spent Nuclear Fuel from Decommissioned Nuclear Power Stations (December)].Under the developing consensus to proceed with closed fuel cycles, it will be necessary to develop SNF separation facilities with stringent requirements upon separation processes and upon generation of only highly resistant waste forms. The location of such facilities at the interim storage sites would offer great benefits to those sites and assure their long term viability by returning them to their original status.The switch from once-through to closed fuel cycle will require extensive time and development work as illustrated in “The Path to Sustainable Nuclear Energy” [DOE, 2005. The Path to Sustainable Nuclear Energy. Basic and Applied Research Opportunities for Advanced Fuel Cycles. DOE (September)]. A carefully crafted long term program, funded for at least 5 years, managed by a strong joint government–industry team, and subjected to regular independent reviews should be considered to assure the program stability and success.The new uncertainty about Yucca Mountain role raises two key issues: (a) what to do with the weapons and other high level government wastes committed to be moved to Yucca Mountain by specified dates? And (b) can the $13.6 billion invested at Yucca Mountain be salvaged if the NRC approves the license submittal and the opposition relents after contentious hearings? Or will it take contingent actions, or, a switch to a partial closed fuel cycle with its reduced risks and earlier timing of their peak risk value? Only time will tell if any of these alternates will be acceptable but, they all reinforce the need for interim storage for commercial SNF.If the decision is to go to a new repository one wonders whether the time has not come to change the safety evaluation process for geological repositories by characterizing two to three sites and subjecting them to an arbitrary release of the fission products in the HLW to be stored and considering the forms of some of the HLW to reduce their peak risks. It would allow the proper choice to be made among the selected sites and to have a basis for convincing the local committee to accept the repository location. It may even decide whether the CONFU fuel assembly [MIT, 2006. Implications of alternative strategies for transition to sustainable fuel cycles. Nucl. Sci. Eng., 154 (September)] for pressurized water reactors can be accommodated in a once-through fuel cycle as suggested by Levy [Levy, S., 2008. Yucca backup plan. Nucl. Eng. Int., 24–28]. A similar configuration is possible in boiling water reactors.  相似文献   
79.
Unlike desktop PC or server applications, multicore devices used in embedded systems are many and diverse. There are many potential approaches to solving the numerous multicore-related issues. The articles in this issue on embedded multicore processors and systems represent a small sampling of these issues.  相似文献   
80.
In a recent study, J. Tedeschi and T. Levy (see record 1971-28825-001) related responsiveness to social reinforcement in chance vs. skill tasks to previous findings of external control in lower-class blacks and internal control in middle-class whites. In the present article, P. Burgess examines the rationale behind Tedeschi and Levy's predictions, questions the validity of their experimental paradigm, and suggests that their results do not provide adequate support for their conclusions. In a separate article, Tedeschi & Levy reply to Burgess's criticisms. (22 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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