1,796 research outputs found

    Evaluating LANDSAT-4 MSS and TM data

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    Interband line pixel misregistrations were determined for the four MSS bands of the Mistassini, Ontario scene and multitemporal registration of LANDSAT-4 products were tested for two different geocoded scenes. Line and pixel misregistrations are tabulated as determined by the manual ground control points and the digital band to band correlation techniques. A method was developed for determining the spectral information content of TM images for forestry applications

    Discussion of Recent Decisions

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    Microbiology and atmospheric processes: Biological, physical and chemical characterization of aerosol particles

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    The interest in bioaerosols has traditionally been linked to health hazards for humans, animals and plants. However, several components of bioaerosols exhibit physical properties of great significance for cloud processes, such as ice nucleation and cloud condensation. To gain a better understanding of their influence on climate, it is therefore important to determine the composition, concentration, seasonal fluctuation, regional diversity and evolution of bioaerosols. In this paper, we will review briefly the existing techniques for detection, quantification, physical and chemical analysis of biological particles, attempting to bridge physical, chemical and biological methods for analysis of biological particles and integrate them with aerosol sampling techniques. We will also explore some emerging spectroscopy techniques for bulk and single-particle analysis that have potential for in-situ physical and chemical analysis. Lastly, we will outline open questions and further desired capabilities (e. g., in-situ, sensitive, both broad and selective, on-line, time-resolved, rapid, versatile, cost-effective techniques) required prior to comprehensive understanding of chemical and physical characterization of bioaerosols

    Biologic Agents—A Panacea for Inflammatory Arthritis or Not?

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    Aim. To describe the retention rates for biological therapies in patients with rheumatoid arthritis (RA), psoriatic arthritis (PsA), and ankylosing spondylitis (AS) in a clinical setting. Methods. All patients managed in a dedicated biological therapy clinic in a teaching hospital in Australia were assessed for continuation on biological treatments and reasons for switching to an alternative biological agent or cessation of treatment. Results. There was a lower retention rate for RA patients on biological therapies compared to PsA and AS patients and the retention rate for RA patients was lower than that reported in RCTs. Conclusions. The retention rate on biological therapies for RA patients was lower in the clinic setting than what is reported in RCTs. The reasons for the lower retention rate in the clinical setting are discussed but no clear determinants for nonresponse to biological agents were identifiable. These agents have very limited steroid sparing effects

    The Productivity of Wh- Prompts in Child Forensic Interviews.

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    Child witnesses are often asked wh- prompts (what, how, why, who, when, where) in forensic interviews. However, little research has examined the ways in which children respond to different wh- prompts, and no previous research has investigated productivity differences among wh- prompts in investigative interviews. This study examined the use and productivity of wh- prompts in 95 transcripts of 4- to 13-year-olds alleging sexual abuse in child investigative interviews. What-how questions about actions elicited the most productive responses during both the rapport building and substantive phases. Future research and practitioner training should consider distinguishing among different wh- prompts.This research was supported in part by the Nuffield Foundation, Jacobs Foundation, an NICHD Grant HD047290, and an ESRC studentship.This is the author accepted manuscript. The final version is available from SAGE via http://dx.doi.org/10.1177/088626051562108

    Fluorescent Excitation of Spectral Lines in Planetary Nebulae

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    Fluorescent excitation of spectral lines is demonstrated as a function of temperature-luminosity and the distance of the emitting region from the central stars of planetary nebulae. The electron densities and temperatures are determined, and the method is exemplified through a detailed analysis of spectral observations of a high excitation PN, NGC 6741, observed by Hyung and Aller(1997). Fluorescence should also be important in the determination of element abundances. It is suggested that the method could be generally applied to determine or constrain the luminosity and the region of spectral emission in other intensively radiative sources such as novae, supernovae, and active galactic nuclei.Comment: 5 pages, 4 figures (fig.4 in color), ApJ (in press

    Production of Secondary Organic Aerosol During Aging of Biomass Burning Smoke From Fresh Fuels and Its Relationship to VOC Precursors

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    After smoke from burning biomass is emitted into the atmosphere, chemical and physical processes change the composition and amount of organic aerosol present in the aged, diluted plume. During the fourth Fire Lab at Missoula Experiment, we performed smog-chamber experiments to investigate formation of secondary organic aerosol (SOA) and multiphase oxidation of primary organic aerosol (POA). We simulated atmospheric aging of diluted smoke from a variety of biomass fuels while measuring particle composition using high-resolution aerosol mass spectrometry. We quantified SOA formation using a tracer ion for low-volatility POA as a reference standard (akin to a naturally occurring internal standard). These smoke aging experiments revealed variable organic aerosol (OA) enhancements, even for smoke from similar fuels and aging mechanisms. This variable OA enhancement correlated well with measured differences in the amounts of emitted volatile organic compounds (VOCs) that could subsequently be oxidized to form SOA. For some aging experiments, we were able to predict the SOA production to within a factor of 2 using a fuel-specific VOC emission inventory that was scaled by burn-specific toluene measurements. For fires of coniferous fuels that were dominated by needle burning, volatile biogenic compounds were the dominant precursor class. For wiregrass fires, furans were the dominant SOA precursors. We used a POA tracer ion to calculate the amount of mass lost due to gas-phase oxidation and subsequent volatilization of semivolatile POA. Less than 5% of the POA mass was lost via multiphase oxidation-driven evaporation during up to 2 hr of equivalent atmospheric oxidation

    Cognitive and behavioural strategies employed to overcome "lapses" and prevent "relapse" among weight-loss maintainers and regainers: A qualitative study.

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    While many behavioural weight management programmes are effective in the short-term, post-programme weight regain is common. Overcoming "lapses" and preventing "relapse" has been highlighted as important in weight-loss maintenance, but little is known on how this is achieved. This study aimed to compare the cognitive and behavioural strategies employed to overcome "lapses" and prevent "relapse" by people who had regained weight or maintained weight-loss after participating in a weight management programme. By investigating differences between groups, we intended to identify strategies associated with better weight-loss maintenance. Semi-structured interviews were conducted with 26 participants (58% female) recruited from the 5-year follow-up of the Weight Loss Referrals for Adults in Primary Care (WRAP) trial (evaluation of a commercial weight-loss programme). Participants who had lost ≥5% baseline weight during the active intervention were purposively sampled according to 5-year weight trajectories (n = 16 'Regainers', n = 10 'Maintainers'). Interviews were audio-recorded, transcribed verbatim, and analysed thematically. Key differences in strategies were that Maintainers continued to pay attention to their dietary intake, anticipated and planned for potential lapses in high-risk situations, and managed impulses using distraction techniques. Regainers did not report making plans, used relaxed dietary monitoring, found distraction techniques to be ineffective and appeared to have difficulty navigating food within interpersonal relationships. This study is one of the longest qualitative follow-ups of a weight loss trial to date, offering unique insights into long-term maintenance. Future programmes should emphasize strategies focusing on self-monitoring, planning and managing interpersonal relationships to help participants successfully maintain weight-loss in the longer-term.This study is funded by the National Institute for Health Research (NIHR) Programme Grants for Applied Research RP-PG-0216-20010. The views expressed are those of the authors and not necessarily those of the NIHR or the Department of Health and Social Care. ALA and SJG are supported by the Medical Research Council (MC_UU_12015/4). SJG is an NIHR senior investigator. The University of Cambridge has received salary support in respect of SJG from the National Health Service in the East of England through the Clinical Academic Reserve

    Mechanisms by which sialylated milk oligosaccharides impact bone biology in a gnotobiotic mouse model of infant undernutrition

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    Undernutrition in children is a pressing global health problem, manifested in part by impaired linear growth (stunting). Current nutritional interventions have been largely ineffective in overcoming stunting, emphasizing the need to obtain better understanding of its underlying causes. Treating Bangladeshi children with severe acute malnutrition with therapeutic foods reduced plasma levels of a biomarker of osteoclastic activity without affecting biomarkers of osteoblastic activity or improving their severe stunting. To characterize interactions among the gut microbiota, human milk oligosaccharides (HMOs), and osteoclast and osteoblast biology, young germ-free mice were colonized with cultured bacterial strains from a 6-mo-old stunted infant and fed a diet mimicking that consumed by the donor population. Adding purified bovine sialylated milk oligosaccharides (S-BMO) with structures similar to those in human milk to this diet increased femoral trabecular bone volume and cortical thickness, reduced osteoclasts and their bone marrow progenitors, and altered regulators of osteoclastogenesis and mediators of Th2 responses. Comparisons of germ-free and colonized mice revealed S-BMO-dependent and microbiota-dependent increases in cecal levels of succinate, increased numbers of small intestinal tuft cells, and evidence for activation of a succinate-induced tuft cell signaling pathway linked to Th2 immune responses. A prominent fucosylated HMO, 2'-fucosyllactose, failed to elicit these changes in bone biology, highlighting the structural specificity of the S-BMO effects. These results underscore the need to further characterize the balance between, and determinants of, osteoclastic and osteoblastic activity in stunted infants/children, and suggest that certain milk oligosaccharides may have therapeutic utility in this setting
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