A Semi-empirical Mass-loss Rate in Short-period Cataclysmic Variables

The mass-loss rate of donor stars in cataclysmic variables (CVs) is of paramount importance in the evolution of short-period CVs. Observed donors are oversized in comparison with those of isolated single stars of the same mass, which is thought to be a consequence of the mass loss. Using the empirical mass-radius relation of CVs and the homologous approximation for changes in effective temperature T_2, orbital period P, and luminosity of the donor with the stellar radius, we find the semi-empirical mass-loss rate M2_dot of CVs as a function of P. The derived M2_dot is at ~10^(-9.5)-10^(-10) Msun/yr and depends weakly on P when P > 90 min, while it declines very rapidly towards the minimum period when P < 90 min, emulating the P-T_2 relation. Due to strong deviation from thermal equilibrium caused by the mass loss, the semi-empirical M2_dot is significantly different from, and has a less-pronounced turnaround behavior with P than suggested by previous numerical models. The semi-empirical P-M2_dot relation is consistent with the angular momentum loss due to gravitational wave emission, and strongly suggests that CV secondaries with 0.075 Msun < M_2 < 0.2 Msun are less than 2 Gyrs old. When applied to selected eclipsing CVs, our semi-empirical mass-loss rates are in good agreement with the accretion rates derived from the effective temperatures T_1 of white dwarfs, suggesting that M2_dot can be used to reliably infer T_2 from T_1. Based on the semi-empirical M2_dot, SDSS 1501 and 1433 systems that were previously identified as post-bounce CVs have yet to reach the minimal period.Comment: 29 pages, 8 figures, 2 tables; accepted for publication in the Ap

The Irritable Bowel Syndrome

A 45 year old businessman presents at your clinic with a 2 year history of recurrent abdominal pain, associated with frequent bouts of diarrhoea. The pain is relieved by defaecation, but there is often a feeling of incomplete evacuation. Between these episodes he is often constipated, with infrequent bowel motions characterised by hard stools. During stressful situations, symptoms get worse and are associated with abdominal bloating and increased flatulence. He researched his problem on the internet and thinks he might have Irritable Bowel Syndrome.peer-reviewe

Annual report of research progress

The mineral and human resources of a state and/or nation are to a large extent the basis of a strong and flourishing economy. In Alaska this is currently illustrated by the activities of the oil and gas industry and the resulting large sums of money that have gone into the state Treasury to help give a sound financial basis to Alaska. The Mineral Industry Research Laboratory has concentrated its efforts on research that will help in the more complete utilization of Alaska's mineral resources for work in the state's mineral industry. This report describes in moderate detail the projects that have been undertaken. These are in the areas of mineral economics, exploration, mining, mineral benefication, beach and ocean mining, utilization of nonmetallics, use of coal resources, and the solving of numerous' specific problems posed by mining people of the state. Training of young men and women for the mineral industry is stimulated by their having the opportunity to work on projects as a part of their graduate program under the supervision of the staff of MIRL. Theses completed offer a considerable amount of information to the public. Recent completed theses are listed in this report. The laboratory has been supported financially by the state of Alaska and various grants and work in kind from individuals and agencies. Private industry has helped in purchasing equipment and cooperative projects are underway with government agencies. Personnel and facilities of the College of Earth Sciences and Mineral Industry supplemented by other professional personnel are involved in teaching and research as set forth in enabling legislation for the Laboratory. The Staff MIR

Predictors of Failure from Primary Therapy for Giardiasis in San Diego: A Single Institution Retrospective Review.

This study aimed to determine the presence of giardiasis among HIV patients in San Diego, the rate of failure of metronidazole treatment, and factors associated with treatment failure. We used a 7 year retrospective single-center case series of HIV-infected individuals with giardiasis at University of California San Diego Medical Center. Data were analyzed for the changes in the hematological, biochemical, and immunologic results at pre- and at-diagnosis levels. We also compared the changes at the diagnosis level among patients who were treated successfully and those who experienced treatment failure as defined by retreatment with a second course of antibiotics. In 29 Giardia lamblia-infected HIV patients, following diagnosis of G. lamblia, there was a non-significant decrement in cluster of differentiation 4 (CD4), but a statistically significant increase in the number of white blood cell (WBC). Other indices did not differ between pre- and at-diagnosis levels. Twenty patients (69%) were treated with a single course of metronidazole or tinidazole and seven patients (24.1%) were treated with more than one course of metronidazole. These seven patients had statistically significant higher hemoglobin at the time of diagnosis, but further studies are required to confirm if this is a consistent finding and if this can predict failure from primary therapy

Nonesophageal Eosinophilic Gastrointestinal Disorders: Clinical Care and Future Directions

Eosinophilic gastrointestinal disorders are a set of conditions with a wide range of clinical manifestations and treatment modalities. The disorders are suspected to result from an abnormal inflammatory response to allergen(s), and individuals may develop a relapsing or chronic disease, if the allergen is not eliminated. Mechanisms of disease pathogenesis, including the humoral immune response, need to be fully elucidated. A variety of therapies are used, though there is a lack of well-defined randomized, prospective studies. Other therapeutic options are needed as the current treatments have potential concerns; elimination diets may impair a child’s quality of life, and corticosteroids have adverse risks with long-term use. We review what is known about non-esophageal eosinophilic gastrointestinal disorders, and discuss research investigations which need to be conducted to facilitate diagnosis and enhance treatment methods

Signature of the presence of a third body orbiting around XB 1916-053

The ultra-compact dipping source \object{XB 1916-053} has an orbital period of close to 50 min and a companion star with a very low mass (less than 0.1 M$_{\odot}$). The orbital period derivative of the source was estimated to be $1.5(3) \times 10^{-11}$ s/s through analysing the delays associated with the dip arrival times obtained from observations spanning 25 years, from 1978 to 2002. The known orbital period derivative is extremely large and can be explained by invoking an extreme, non-conservative mass transfer rate that is not easily justifiable. We extended the analysed data from 1978 to 2014, by spanning 37 years, to verify whether a larger sample of data can be fitted with a quadratic term or a different scenario has to be considered. We obtained 27 delays associated with the dip arrival times from data covering 37 years and used different models to fit the time delays with respect to a constant period model.We find that the quadratic form alone does not fit the data. The data are well fitted using a sinusoidal term plus a quadratic function or, alternatively, with a series of sinusoidal terms that can be associated with a modulation of the dip arrival times due to the presence of a third body that has an elliptical orbit. We infer that for a conservative mass transfer scenario the modulation of the delays can be explained by invoking the presence of a third body with mass between 0.10-0.14 M$_{\odot}$, orbital period around the X-ray binary system of close to 51 yr and an eccentricity of $0.28 \pm 0.15$. In a non-conservative mass transfer scenario we estimate that the fraction of matter yielded by the degenerate companion star and accreted onto the neutron star is $\beta = 0.08$, the neutron star mass is $\ge 2.2$ M$_{\odot}$, and the companion star mass is 0.028 M$_{\odot}$. (Abridged)Comment: 13 pages, 9 figures. Accepted for publication in A&

Comparison of symptoms, healthcare utilization, and treatment in diagnosed and undiagnosed individuals with diarrhea-predominant irritable bowel syndrome

OBJECTIVES: Irritable bowel syndrome (IBS) is a functional bowel disorder characterized by symptoms including abdominal pain and altered bowel function. Up to 75% of individuals with IBS may be undiagnosed. The aim of this study was to characterize symptoms, healthcare utilization, and treatments in populations with both diagnosed and undiagnosed IBS. METHODS: An online survey was conducted to compare gastrointestinal (GI) symptoms, healthcare visits, well-being, symptom management, and treatment satisfaction in individuals with and without medically diagnosed IBS (Rome III criteria). Symptom severity, disruptiveness, and treatment satisfaction were rated using a 7-point scale. Adjustments to daily life were determined by predefined survey responses. RESULTS: A total of 1,924 individuals with a history of GI symptoms were eligible and completed the survey. Of these, 1,094 individuals (56.9%) met the criteria for IBS; 830 individuals (43.1%) had no medical diagnosis of IBS despite meeting diagnostic criteria. Most participants received a diagnosis from either gastroenterologists (45%) or primary care physicians (42%). A greater percentage of diagnosed patients had severe GI symptoms (score ≥6) vs. undiagnosed individuals (16% vs. 8%, respectively; P&lt;0.05); diagnosed patients were more likely to report that GI symptoms adversely affected their quality of life. Approximately 40% of participants received IBS-related treatment from primary care physicians; 26% and 43% of diagnosed and undiagnosed individuals, respectively, were not receiving treatment for GI symptoms. CONCLUSIONS: Many individuals with IBS-related symptoms have not been medically diagnosed with IBS. IBS-related symptoms impact quality of life, yet more than one-third of individuals are not receiving treatment for IBS