5,855 research outputs found

    Haze in the Klang Valley of Malaysia

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    Continuous measurements of dry aerosol light scattering (Bsp) were made at two sites in the Klang Valley of Malaysia between December 1998 and December 2000. In addition 24-h PM2.5 samples were collected on a one-day-in-six cycle and the chemical composition of the aerosol was determined. Periods of excessive haze were defined as 24-h average Bsp values greater than 150 Mm-1 and these occurred on a number of occasions, between May and September 1999, during May 2000, and between July and September 2000. The evidence for smoke being a significant contributor to aerosol during periods of excessive haze is discussed and includes features of the aerosol chemistry, the diurnal cycle of Bsp, and the coincidence of forest fires on Sumatra during the southwest (SW) monsoon period, as well as transport modelling for one week of the southwest Monsoon of 2000. The study highlights that whilst transboundary smoke is a major contributor to poor visibility in the Klang Valley, smoke from fires on Peninsular Malaysia is also a contributor, and at all times, the domestic source of secondary particle production is present

    Measurement of Resonant Frequency and Quality Factor of Microwave Resonators: Comparison of Methods

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    Precise microwave measurements of sample conductivity, dielectric, and magnetic properties are routinely performed with cavity perturbation measurements. These methods require the accurate determination of quality factor and resonant frequency of microwave resonators. Seven different methods to determine the resonant frequency and quality factor from complex transmission coefficient data are discussed and compared to find which is most accurate and precise when tested using identical data. We find that the nonlinear least-squares fit to the phase vs. frequency is the most accurate and precise when the signal-to-noise ratio is greater than 65. For noisier data, the nonlinear least squares fit to a Lorentzian curve is more accurate and precise. The results are general and can be applied to the analysis of many kinds of resonant phenomena.Comment: 29 pages, 11 figure

    Perceived Entitlement to Pain-Related Support and Pain Catastrophizing: Associations with Perceived and Observed Support

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    Studies on the determinants of pain-related support are needed to enhance couples-based treatments for pain. The purpose of this study was to determine the extent to which pain catastrophizing and perceived entitlement to pain-related support (i.e., support entitlement) were associated with perceived and observed social support. Participants were 106 chronic pain couples recruited from the community. They completed surveys as well as an observational discussion task. Greater support entitlement in persons with pain was correlated positively with pain catastrophizing, punishing spouse responses, and observed spousal invalidation but negatively correlated with perceived spousal support, solicitous spouse responses, and observed validation. Catastrophizing was correlated with perceptions of general spousal support but not the other support variables. Hierarchical regression analyses demonstrated that among persons with lower levels of support entitlement, catastrophizing was associated with greater solicitous spouse responses. Among those with a greater entitlement to support, catastrophizing was associated with greater punishing spouse responses and observed invalidation by the spouse. These results suggest that support entitlement plays an important role in couples’ supportive interactions about pain. Continued research is needed to determine how a desire for pain-related attention and support and catastrophizing translate into behaviors that affect support provision and receipt

    A millimeter-wave antireflection coating for cryogenic silicon lenses

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    We have developed and tested an antireflection (AR) coating method for silicon lenses at cryogenic temperatures and millimeter wavelengths. Our particular application is a measurement of the cosmic microwave background. The coating consists of machined pieces of Cirlex glued to the silicon. The measured reflection from an AR coated flat piece is less than 1.5% at the design wavelength. The coating has been applied to flats and lenses and has survived multiple thermal cycles from 300 to 4 K. We present the manufacturing method, the material properties, the tests performed, and estimates of the loss that can be achieved in practical lenses

    Design and fabrication of 3D-printed anatomically shaped lumbar cage for intervertebra disc (IVD) degeneration treatment

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    Spinal fusion is the gold standard surgical procedure for degenerative spinal conditions when conservative therapies have been unsuccessful in rehabilitation of patients. Novel strategies are required to improve biocompatibility and osseointegration of traditionally used materials for lumbar cages. Furthermore, new design and technologies are needed to bridge the gap due to the shortage of optimal implant sizes to fill the intervertebral disc defect. Within this context, additive manufacturing technology presents an excellent opportunity to fabricate ergonomic shape medical implants. The goal of this study is to design and manufacture a 3D-printed lumbar cage for lumbar interbody fusion. Optimisations of the proposed implant design and its printing parameters were achieved via in silico analysis. The final construct was characterised via scanning electron microscopy, contact angle, x-ray micro computed tomography (ÎŒCT), atomic force microscopy, and compressive test. Preliminary in vitro cell culture tests such as morphological assessment and metabolic activities were performed to access biocompatibility of 3D-printed constructs. Results of in silico analysis provided a useful platform to test preliminary cage design and to find an optimal value of filling density for 3D printing process. Surface characterisation confirmed a uniform coating of nHAp with nanoscale topography. Mechanical evaluation showed mechanical properties of final cage design similar to that of trabecular bone. Preliminary cell culture results showed promising results in terms of cell growth and activity confirming biocompatibility of constructs. Thus for the first time, design optimisation based on computational and experimental analysis combined with the 3D-printing technique for intervertebral fusion cage has been reported in a single study. 3D-printing is a promising technique for medical applications and this study paves the way for future development of customised implants in spinal surgical applications

    Continuing professional development for LIS professionals: Maximizing potential in an organizational context

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    Library and information science (LIS) professionals must be engaged in continuing professional development (CPD) to ensure their skills, knowledge and capabilities regularly to meet their own objectives and the requirements of employer organizations. This article highlights crucial issues relating to CPD in the interrelated contexts of the individual professional and their employer organization. We address three rhetorical questions: Are we willing to learn? Do we have opportunities to learn? Are we able to apply what we learn? Discussion and recommendations are drawn from relevant literature and grounded in workplace experience. Included are exemplar case studies from a large Australian academic library. Individuals' motivation and learning skill levels have significant impact on CPD effectiveness, as does the organizational learning climate. Professionals and employers jointly bear responsibility for CPD outcomes. LIS professionals should reflect on what motivates them towards continuous learning and organizations must create supportive learning environments. We find that both staff and employers are responsible for sourcing learning opportunities and utilizing effective learning transfer strategies. In this context, we recommend that a deliberate and thoughtful approach to CPD as this will result in increased benefits to LIS professionals and organizations

    Getting published: group support for academic librarians

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    Purpose - The purpose of this paper is to offer an effective model for increasing professionals' competence, enthusiasm and success in writing and publishing. Design/methodology/approach - Recent articles on writing groups in the field of library and information science are reviewed and a case study of a group at RMIT University Library is presented. The authors were the facilitator and group members who were librarians, most with relative inexperience in research, writing, presenting, and getting published. A self-rating confidence survey was created to establish developmental priorities which were then addressed through input from experts, practical application and reflection, and constructive advice and support from group members. Group effectiveness and outcomes were evaluated at mid- and end-point review meetings, through a post-intervention confidence survey and by tracking publication output. Findings - The group became a cohesive, task-focused and productive team. A post-intervention confidence survey evidenced improvements on all survey items at a team level. Each member affirmed that they had gained substantial knowledge of writing, presentation and research techniques and understanding of the publication process. Publication output increased over the benchmark year of 2010, and in 2011 and 2012 exceeded initial targets. Practical implications - The model presented offers a practical and effective approach to increasing competence and output in writing, presenting, research, and getting published and can be easily adopted by others. Originality/value - Most literature reviews on library professional writing groups relate to professionals required to publish. The Get Published Group comprised Australian librarians writing voluntarily

    Are patterns of fine-scale spatial genetic structure consistent between sites within tropical tree species?

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    JRS was funded by the Swiss National Science Foundation (SNF) (http://www.snf.ch/en/Pages/default.aspx) grant number PDFMP3_132479 / 1 awarded to JG. The funder had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Peer reviewedPublisher PD

    The timed barium swallow and its relationship to symptoms in achalasia: Analysis of surface area and emptying rate

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    BACKGROUND: Timed barium swallow (TBS) is used to objectively measure response following achalasia therapy; however, findings can be discordant with symptoms. We hypothesized that measurement of surface area of the residual barium column would improve its utility in measuring outcome. METHODS: In a single-center cohort, achalasia patients undergoing therapy between September 2015-2016 who had TBS were included. Four metrics of emptying were studied: Post-therapy residual barium (a) absolute height and (b) surface area and percentage reduction in (c) residual height (%H) and (d) surface area (%SA) compared to pretherapy. Metrics were evaluated against symptom response (Eckardt score). KEY RESULTS: Twenty-four achalasics (median age 43 year; 13 males) were included; 14 received pneumatic dilatation, and 10 had peroral endoscopic myotomy. Treatment resulted in significant reduction in median Eckardt score (7 to 1; P = .03), mean residual barium column height (14.7 ± 8.7 to 7.9 ± 6.0 cm; P = .01) and surface area (52.7 ± 43.5 to 24.5 ± 23.6 cm2 ; P = .02). There were 4 (17%) initial non-responders (Eckardt > 3). % SA was best at discriminating between responders and non-responders (area under curve 0.85 ± 0.08; sensitivity 100%, specificity 80%). Concordance with symptomatic response following therapy was 83% when using 45% as the cutoff for surface area reduction compared to pretherapy. Eight patients whose static barium height was discordant with symptoms became concordant when % SA was used as a measure of response. CONCLUSIONS & INFERENCES: Change in barium surface area is a superior measure of esophageal emptying and better correlates with treatment response than the conventional 5-minute barium height in defining objective response to achalasia therapy
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