5,701 research outputs found

    Junction range finder

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    Electronic system locates interferences in radar reception. System utilizes well known frequency-modulated continuous-wave technique to locate objects with nonlinear impedances. FM transmitter generates signal through bandpass filter which eliminates higher order harmonics around carrier frequency

    A review of melt and vapor growth techniques for polydiacetylene thin films for nonlinear optical applications

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    Methods for the growth of polydiacetylene thin films by melt and vapor growth and their subsequent polymerization are summarized. Films with random orientations were obtained when glass or quartz were used as substrates in the vapor growth process. Oriented polydiacetylene films were fabricated by the vapor deposition of diacetylene monomer onto oriented polydiacetylene on a glass substrate and its subsequent polymerization by UV light. A method for the growth of oriented thin films by a melt-shear growth process as well as a method of film growth by seeded recrstallization from the melt between glass plates, that may be applied to the growth of polydiacetylene films, are described. Moreover, a method is presented for the fabrication of single crystal thin films of polyacetylenes by irradiation of the surface of diacetylene single crystals to a depth between 100 and 2000 angstroms

    A preliminary review of organic materials single crystal growth by the Czochralski technique

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    The growth of single crystals of organic compounds by the Czochralski method is reviewed. From the literature it is found that single crystals of benzil, a nonlinear optical material with a d sub 11 value of 11.2 + or - 1.5 x d sub 11 value of alpha quartz, has fewer dislocations than generally contained in Bridgman crystals. More perfect crystals were grown by repeated Czochralski growth. This consists of etching away the defect-containing portion of a Czochralski grown crystal and using it as a seed for further growth. Other compounds used to grow single crystals are benzophenone, 12-tricosanone (laurone), and salol. The physical properties, growth apparatus, and processing conditions presented in the literature are discussed. Moreover, some of the possible advantages of growing single crystals of organic compounds in microgravity to obtain more perfect crystals than on Earth are reviewed

    William G. Frazier Interview

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    Transcript of oral history interview with William G. Frazier by Mike Downs on his experiences during the Vietnam War on February 25, 1984

    Acceptability and proof of concept of internet-delivered treatment for depression, anxiety, and stress in university students: protocol for an open feasibility trial

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    BACKGROUND: In recent years, university counseling and mental health services have reported an increase in the number of clients seeking services and in yearly visits. This trend has been observed at many universities, indicating that behavioral and mental health issues pose significant problems for many college students. The aim of this study is to assess the acceptability and proof of concept of internet-delivered treatment for depression, anxiety, and stress for university students. METHODS/DESIGN: The study is an open feasibility trial of the SilverCloud programs for depression (Space from Depression), anxiety (Space from Anxiety), and stress (Space from Stress). All three are 8-module internet-delivered CBT (iCBT) intervention programs. Participants are assigned a supporter who provides weekly feedback on progress and exercises. Participants will complete the Patient Health Questionnaire-9 (PHQ-9), Generalized Anxiety Disorder-7 (GAD-7), and stress subscale of the Depression, Anxiety, Stress Scale-21 (DASS-21) as the outcome measures for the depression, anxiety, and stress interventions, respectively. Other outcomes include measures of acceptability of, and satisfaction, with the intervention. Data will be collected at baseline, 8 weeks and 3-month follow-up. DISCUSSION: It is anticipated that the study will inform the researchers and service personnel of the programs' potential to reduce depression, anxiety, and stress in a student population as well as the protocols to be employed in a future trial. In addition, it will provide insight into students' engagement with the programs, their user experience, and their satisfaction with the online delivery format

    Solid-state NMR Analysis of Adhesive Bondlines in Pilot Scale Flakeboards

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    This work demonstrates the application of solid-state NMR to the analysis of adhesive bondlines in pilot scale flakeboards. A comparison to laboratory scale experiments is also made. Phenol-formaldehyde resin is easily detected by using labeled formaldehyde. However, resin washout can occasionally prevent detection in pilot scale composites. The relative degree of resin cure is determined by measuring corrected signal areas and also by measuring proton longitudinal relaxation in the rotating frame. Such relaxation measurements were effective in laboratory scale experiments, but were much less useful for pilot scale tests. The degree of phenol-formaldehyde polymerization was not affected by changes in wood furnish moisture content; the range of furnish moisture was 13 and 24%. This suggests that phenol-formaldehyde moisture intolerance is not related to polymerization retardation by water. This work demonstrates the feasibility of performing detailed bondline analyses on pilot and possibly industrial scale composites

    Supported internet-delivered cognitive behavioral therapy programs for depression, anxiety, and stress in university students: open, non-randomised trial of acceptability, effectiveness, and satisfaction

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    BACKGROUND: Many university campuses have limited mental health services that cannot cope with the high demand. One alternative is to use internet-delivered cognitive behavioral therapy (iCBT) as a way of tackling barriers such as lack of availability and scheduling issues. OBJECTIVE: This study aimed to assess feasibility, acceptability, effectiveness, and satisfaction of a supported iCBT intervention offering 3 programs on depression, anxiety, and stress to university students. The design was an open or nonrandomized feasibility trial. METHODS: Participants were recruited from 3 counseling centers at a large midwestern University in the United States. Those agreeing to take part chose 1 of 3 iCBT programs-Space from Depression, Space from Anxiety, or Space from Stress -all comprised 8 modules of media-rich interactive content. Participants were supported throughout the trial by a trained professional. The Patient Health Questionnaire 9 (PHQ-9), Generalized Anxiety Disorder 7 (GAD-7) questionnaire, and stress subscale of the Depression Anxiety and Stress Scale (DASS-21) were completed at baseline, 8 weeks, and 3-month follow-up. A Satisfaction With Treatment (SAT) questionnaire was completed at 8 weeks, and qualitative interviews were completed by a subsample of participants at 3 months. RESULTS: A total of 102 participants were recruited, with 52 choosing Space from Anxiety, 31 choosing Space from Depression, and 19 choosing Space from Stress. Mixed-effects models showed a significant decrease in symptoms of depression (Fâ‚„=6.36, P<.001), anxiety (Fâ‚„=7.97, P<.001), and stress (Fâ‚„=8.50, P<.001) over time across all 3 programs. The largest decreases in PHQ-9 scores at 8 weeks were among participants who chose the Space from Depression program (d=0.84); at 3 months, the largest decreases in PHQ-9 scores were among those who chose the Space from Stress program (d=0.74). The largest decreases in GAD-7 scores were among those who chose the Space from Anxiety program (d=0.74 at 8 weeks and d=0.94 at 3 months). The largest decrease in DASS-21 stress subscale scores was among those who chose the Space from Stress program (d=0.49 at 8 weeks and d=1.16 at 3 months). The mean time spent using the platform per session was 27.4 min (SD 33.8), and participants completed 53% (SD 37.6) of the total program content on average. Most (37/53, 69%) participants found the programs helpful or very helpful and liked the convenience and flexibility of the intervention. Qualitative interviews (n=14) indicated the intervention met students' expectations, and they saw it as a valuable complement to face-to-face treatment. CONCLUSIONS: The iCBT programs tested in our study appear to be feasible, acceptable, and effective in a university environment. Participants described the benefits of having a flexible, supported Web-based intervention available on campus. Larger trials should be conducted to further test the effectiveness of supported Web-based interventions that give students a choice of program depending on their symptom profile.Published versio
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