Kaon-nucleon and D-nucleon scattering in the quark model, including spin-orbit interactions

Interactions of charmed and strange mesons with baryonic matter can be calculated in the nonrelativistic quark potential model. For KN scattering data exists, and the theoretical results for S-waves are in approximate agreement with experiment. Here we apply the same model to the scattering of open-charm (D) mesons by nucleons, and give quark model predictions for DN scattering amplitudes. Spin-orbit forces in KN and DN will also be discussed.Comment: 5 pages, 14 figures. Presented at Strange Quarks in Matter 2001 - A Flavourspace Odyssey (Frankfurt, 25-29 Sept. 2001

Rapid Detection and Quantification of Triacylglycerol by HPLC–ELSD in \u3ci\u3eChlamydomonas reinhardtii\u3c/i\u3e and \u3ci\u3eChlorella\u3c/i\u3e Strains

Triacylglycerol (TAG) analysis and quantification are commonly performed by first obtaining a purified TAG fraction from a total neutral lipid extract using thinlayer chromatography (TLC), and then analyzing the fatty acid composition of the purified TAG fraction by gas chromatography (GC). This process is time-consuming, labor intensive and is not suitable for analysis of small sample sizes or large numbers. A rapid and efficient method for monitoring oil accumulation in algae using high performance liquid chromatography for separation of all lipid classes combined with detection by evaporative light scattering (HPLC–ELSD) was developed and compared to the conventional TLC/GC method. TAG accumulation in two Chlamydomonas reinhardtii (21 gr and CC503) and three Chlorella strains (UTEX 1230, CS01 and UTEX 2229) grown under conditions of nitrogen depletion was measured. The TAG levels were found to be 3–6 % DW (Chlamydomonas strains) and 7–12 % DW (Chlorella strains) respectively by both HPLC–ELSD and TLC/GC methods. HPLC–ELSD resolved the major lipid classes such as carotenoids, TAG, diacylglycerol (DAG), free fatty acids, phospholipids, and galactolipids in a 15-min run. Quantitation of TAG content was based on comparison to calibration curves of trihexadecanoin (16:0 TAG) and trioctadecadienoin (18:2 TAG) and showed linearity from 0.2 to 10 lg. Algal TAG levels \u3e0.5 lg/g DW were detectable by this method. Furthermore TAG content in Chlorella kessleri UTEX 2229 could be detected. TAG as well as DAG and TAG content were estimated at 1.6 % DWby HPLC–ELSD, while it was undetectable by TLC/GC method

Microglial inhibition of neuroprotection by antagonists of the EP1 prostaglandin E2 receptor

© 2009 Carlson et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens

Common mental disorders among Indigenous people living in regional, remote and metropolitan Australia: a cross-sectional study

Objective: To determine, using face-to-face diagnostic interviews, the prevalence of common mental disorders (CMD) in a cohort of adult Indigenous Australians, the cultural acceptability of the interviews, the rates of comorbid CMD and concordance with psychiatrists’ diagnoses. Design: Cross-sectional study July 2014–November 2016. Psychologists conducted Structured Clinical Interviews for Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision Axis I Disorders (SCID-I) (n=544). Psychiatrists interviewed a subsample (n=78). Setting: Four Aboriginal Medical Services and the general community located in urban, regional and remote areas of Southern Queensland and two Aboriginal Reserves located in New South Wales. Participants: Indigenous Australian adults. Outcome measures: Cultural acceptability of SCID-I interviews, standardised rates of CMD, comorbid CMD and concordance with psychiatrist diagnoses. Results: Participants reported that the SCID-I interviews were generally culturally acceptable. Standardised rates (95% CI) of current mood, anxiety, substance use and any mental disorder were 16.2% (12.2% to 20.2%), 29.2% (24.2% to 34.1%), 12.4% (8.8% to 16.1%) and 42.2% (38.8% to 47.7%), respectively—6.7-fold, 3.8-fold, 6.9- fold and 4.2-fold higher, respectively, than those of the Australian population. Differences between this Indigenous cohort and the Australian population were less marked for 12-month (2.4-fold) and lifetime prevalence (1.3-fold). Comorbid mental disorder was threefold to fourfold higher. In subgroups living on traditional lands in Indigenous reserves and in remote areas, the rate was half that of those living in mainstream communities. Moderate-to- good concordance with psychiatrist diagnoses was found. Conclusions: The prevalence of current CMD in this Indigenous population is substantially higher than previous estimates. The lower relative rates of non-current disorders are consistent with underdiagnosis of previous events. The lower rates among Reserve and remote area residents point to the importance of Indigenous peoples’ connection to their traditional lands and culture, and a potentially important protective factor. A larger study with random sampling is required to determine the population prevalence of CMD in Indigenous Australians

3D inversion of towed streamer EM data: a model study of the Harding field with comparison to CSEM

provide an early study of the challenges involved in validating offshore electromagnetic (EM) data acquired using a towed streamer receiver (currently under development) and compare the results with existing seabed-based marine controlled source electromagnetic (CSEM) technology. T he premise of the various marine controlled source electromagnetic (CSEM) methods is sensitivity to the lateral extents and thicknesses of resistive bodies embedded in conductive hosts. Over the past decade, CSEM surveys have been characterized by arrays of fixed ocean bottom receivers and towed transmitters, and applied to de-risking exploration and appraisal projects with direct hydrocarbon indication. The most successful applications of CSEM to date have been in complement to those seismic interpretations where lithological or fluid variations cannot be adequately discriminated by seismic methods alone (e.g., Hesthammer et al., 2010). However, relatively high acquisition costs have represented a significant obstacle to widespread adoption of conventional CSEM technology, particularly in frontier basins. To this end, a towed streamer system capable of simultaneous seismic and electromagnetic (EM) data acquisition has recently been developed and tested in the North Sea In exploration, hydrocarbon reserves and resources are estimated with varying confidence from volumetrics that are predicted from different 3D earth models and scenarios. Quantitative interpretation of EM data is inherently reliant upon 3D earth models derived from inversion since EM data cannot simply be separated or transformed with linear operators as per seismic methods. However, methods for inverting CSEM data are complicated by the very small, nonunique and non-linear responses of hydrocarbon-bearing reservoir units when compared to the measured total fields. Moreover, 3D inversion of towed streamer EM data poses a significant challenge because of the increased scale of the surveys, the requirement for high resolution models, and the significantly increased number of transmitter-receiver pairs. Inverting towed streamer EM data Large-scale conventional CSEM surveys may have in the order of hundreds of fixed receivers, and in the order of thousands of transmitter positions. Reciprocity is routinely exploited in 3D conventional CSEM modelling and inversion to minimize the number of source terms that need to be solved (e.g.

On the origin of X-shaped radio galaxies

After a brief, critical review of the leading explanations proposed for the small but important subset of radio galaxies showing an X-shaped morphology (XRGs) we propose a generalized model, based on the jet-shell interaction and spin-flip hypotheses. The most popular scenarios for this intriguing phenomenon invoke either hydrodynamical backflows and over-pressured cocoons or rapid jet reorientations, presumably from the spin-flips of central engines following the mergers of pairs of galaxies, each of which contains a supermassive black hole (SMBH). We confront these models with a number of key observations and thus argue that none of the models is capable of explaining the entire range of salient observational properties of XRGs, although some of the arguments raised in the literature against the spin-flip scenario are probably not tenable. We then propose here a new scenario which also involves galactic mergers but would allow the spin of the central engine to maintain its direction. Motivated by the detailed multi-band observations of the nearest radio galaxy, Centaurus A, this new model emphasizes the role of interactions between the jets and the shells of stars and gas that form and rotate around the merged galaxy and can cause temporary deflections of the jets, occasionally giving rise to an X-shaped radio structure. Although each of the models is likely to be relevant to a subset of XRGs, the bulk of the evidence indicates that most of them are best explained by the jet-shell interaction or spin-flip hypotheses.Comment: 19 pages, major revision including two Appendices and a Table, accepted in Research in Astronomy and Astrophysic

Common mental disorders among Indigenous people living in regional, remote and metropolitan Australia: a cross-sectional study

Objective To determine, using face-to-face diagnostic interviews, the prevalence of common mental disorders (CMD) in a cohort of adult Indigenous Australians, the cultural acceptability of the interviews, the rates of comorbid CMD and concordance with psychiatrists' diagnoses. Design Cross-sectional study July 2014–November 2016. Psychologists conducted Structured Clinical Interviews for Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision Axis I Disorders (SCID-I) (n=544). Psychiatrists interviewed a subsample (n=78). Setting Four Aboriginal Medical Services and the general community located in urban, regional and remote areas of Southern Queensland and two Aboriginal Reserves located in New South Wales. Participants Indigenous Australian adults. Outcome measures Cultural acceptability of SCID-I interviews, standardised rates of CMD, comorbid CMD and concordance with psychiatrist diagnoses. Results Participants reported that the SCID-I interviews were generally culturally acceptable. Standardised rates (95% CI) of current mood, anxiety, substance use and any mental disorder were 16.2% (12.2% to 20.2%), 29.2% (24.2% to 34.1%), 12.4% (8.8% to 16.1%) and 42.2% (38.8% to 47.7%), respectively—6.7-fold, 3.8-fold, 6.9-fold and 4.2-fold higher, respectively, than those of the Australian population. Differences between this Indigenous cohort and the Australian population were less marked for 12-month (2.4-fold) and lifetime prevalence (1.3-fold). Comorbid mental disorder was threefold to fourfold higher. In subgroups living on traditional lands in Indigenous reserves and in remote areas, the rate was half that of those living in mainstream communities. Moderate-to-good concordance with psychiatrist diagnoses was found. Conclusions The prevalence of current CMD in this Indigenous population is substantially higher than previous estimates. The lower relative rates of non-current disorders are consistent with underdiagnosis of previous events. The lower rates among Reserve and remote area residents point to the importance of Indigenous peoples' connection to their traditional lands and culture, and a potentially important protective factor. A larger study with random sampling is required to determine the population prevalence of CMD in Indigenous Australians