Soft X-ray emission lines from a relativistic accretion disk in MCG-6-30-15 and Mrk 766

XMM-Newton Reflection Grating Spectrometer (RGS) spectra of the Narrow Line Seyfert 1 galaxies MCG -6-30-15 and Mrk 766 are physically and spectroscopically inconsistent with standard models comprising a power-law continuum absorbed by either cold or ionized matter. We propose that the remarkably similar features detected in both objects in the 5-35 Angstrom band are H-like oxygen, nitrogen, and carbon emission lines, gravitationally redshifted and broadened by relativistic effects in the vicinity of a Kerr black hole. We discuss the implications of our interpretation, and demonstrate that the derived parameters can be physically self-consistent

A cross-sectional study of vascular risk factors in a rural South African population : data from the Southern African Stroke Prevention Initiative (SASPI)

Background: Rural sub-Saharan Africa is at an early stage of economic and health transition. It is predicted that the 21st century will see a serious added economic burden from non-communicable disease including vascular disease in low-income countries as they progress through the transition. The stage of vascular disease in a population is thought to result from the prevalence of vascular risk factors. Already hypertension and stroke are common in adults in sub-Saharan Africa. Using a multidisciplinary approach we aimed to assess the prevalence of several vascular risk factors in Agincourt, a rural demographic surveillance site in South Africa. Methods: We performed a cross sectional random sample survey of adults aged over 35 in Agincourt (population ≈ 70 000). Participants were visited at home by a trained nurse who administered a questionnaire, carried out clinical measurements and took a blood sample. From this we assessed participants' history of vascular risk, blood pressure using an OMRON 705 CP monitor, waist circumference, body mass index (BMI), ankle brachial index (ABI), and total and HDL cholesterol. Results: 402 people (24% men) participated. There was a high prevalence of smoking in men, but the number of cigarettes smoked was small. There was a striking difference in mean BMI between men and women (22.8 kg/m2 versus 27.2 kg/m2), but levels of blood pressure were very similar. 43% of participants had a blood pressure greater than 140/90 or were on anti-hypertensive treatment and 37% of participants identified with measured high blood pressure were on pharmacological treatment. 12% of participants had an ABI of < 0.9, sugesting the presence of sub-clinical atheroma. 25.6% of participants had a total cholesterol level > 5 mmol/l. Conclusion: We found a high prevalence of hypertension, obesity in women, and a suggestion of subclinical atheroma despite relatively favourable cholesterol levels in a rural South African population. South Africa is facing the challenge of an emerging epidemic of vascular disease. Research to establish the social determinates of these risk factors and interventions to reduce both individual and population risk are required

Does hyperprolactinemia affect hepatic regeneration independent of sex steroids?

Prolactin, administered exogeneously, has been shown to be trophic to the liver, causing increases in the liver weight-to-body weight ratio, in ornithine decarboxylase activity, and in thymidine kinase activity. To investigate the effect of endogenous hyperprolactinemia on hepatic regeneration, pituitary isografts were placed beneath the renal capsule in rats 2 weeks before the rats underwent a two-thirds partial hepatectomy. Prolactin levels 2 weeks after the transplant were greater in the animals with the pituitary isografts compared with levels in controls. The increase in the liver weight-to-body weight ratio after hepatectomy was similar in the rats with pituitary transplant and the controls. However, chronic hyperprolactinemia was associated with increased basal levels of ornithine decarboxylase activity and thymidine kinase activity. Both ornithine decarboxylase activity and thymidine kinase activity increased after partial hepatectomy, and the magnitude of the changes was similar for both groups of animals. The levels of estrogen receptor activity before the partial hepatectomy and the reduction in receptor activity that follows partial hepatectomy were similar in the two groups of animals. Moreover, the levels of androgen receptor activity within the liver before partial hepatectomy and the increase in receptor activity after hepatectomy were similar in the two groups of animals. Thus, chronic sustained hyperprolactinemia has no beneficial effect on the hepatic regenerative response, despite induction of both basal ornithine decarboxylase and thymidine kinase activities

Sacrocolpopexy without concomitant posterior repair improves posterior compartment defects

The aim of this study is to determine posterior compartment topography 1-year after sacrocolpopexy (SC). Women who had SC without concomitant anterior or posterior repairs for symptomatic pelvic organ prolapse (POP) were included. Vaginal topography was assessed at baseline and 1-year postoperatively using POP quantification (POPQ). At baseline, 24% had stage IV POP, 68% stage III, and 8% stage II. One year after surgery, 75% had stage 0/I POP, 24% stage II, and 1% stage III. 112 (75%) were objectively cured (stage 0 or I POP). Anterior compartment was the most common site of POP persistence or recurrence (Ba ≥ stage II in 23 women) followed by posterior compartment (Bp ≥ stage II in 12 women) and apex (C ≥ stage II in 2 women). In 1-year follow-up, SC without concomitant posterior repair restores posterior vaginal topography in the majority of women with undergoing SC

Interdisciplinary research: putting the methods under the microscope

BACKGROUND: While the desirability of interdisciplinary inquiry has been widely acknowledged, indeed has become 'the mantra of science policy', the methods of interdisciplinary collaboration are opaque to outsiders and generally remain undescribed. DISCUSSION: Many have analysed interdisciplinarity, especially in relation to the creation of new disciplines and institutions. These analyses are briefly outlined. Still, there currently persists a silence about the methods of interdisciplinary collaboration itself, and the core of this paper proposes a template for such methods. SUMMARY: Breaking this silence – by making the methods of interdisciplinary projects transparent – could further invigorate interdisciplinary research

A Cross-Sectional Study of Barriers to Personal Health Record Use among Patients Attending a Safety-Net Clinic

BACKGROUND: Personal health records (PHR) may improve patients' health by providing access to and context for health information. Among patients receiving care at a safety-net HIV/AIDS clinic, we examined the hypothesis that a mental health (MH) or substance use (SU) condition represents a barrier to engagement with web-based health information, as measured by consent to participate in a trial that provided access to personal (PHR) or general (non-PHR) health information portals and by completion of baseline study surveys posted there. METHODS: Participants were individually trained to access and navigate individualized online accounts and to complete study surveys. In response to need, during accrual months 4 to 12 we enhanced participant training to encourage survey completion with the help of staff. Using logistic regression models, we estimated odds ratios for study participation and for survey completion by combined MH/SU status, adjusted for levels of computer competency, on-study training, and demographics. RESULTS: Among 2,871 clinic patients, 70% had MH/SU conditions, with depression (38%) and methamphetamine use (17%) most commonly documented. Middle-aged patients and those with a MH/SU condition were over-represented among study participants (N = 338). Survey completion was statistically independent of MH/SU status (OR, 1.85 [95% CI, 0.93-3.66]) but tended to be higher among those with MH/SU conditions. Completion rates were low among beginner computer users, regardless of training level (<50%), but adequate among advanced users (>70%). CONCLUSIONS: Among patients attending a safety-net clinic, MH/SU conditions were not barriers to engagement with web-based health information. Instead, level of computer competency was useful for identifying individuals requiring substantial computer training in order to fully participate in the study. Intensive on-study training was insufficient to enable beginner computer users to complete study surveys

A simple index of lipid overaccumulation is a good marker of liver steatosis

<p>Abstract</p> <p>Background</p> <p>Liver steatosis is often found in association with common cardiometabolic disorders, conditions that may all occur in a shared context of abdominal obesity and dyslipidemia. An algorithm for identifying liver steatosis is the fatty liver index (FLI). The lipid accumulation product (LAP) is an index formulated in a representative sample of the US population to identify cardiometabolic disorders. Because FLI and LAP share two components, namely waist circumference and fasting triglycerides, we evaluated the ability of LAP to identify liver steatosis in the same study population from the Northern Italian town where FLI was initially developed.</p> <p>Methods</p> <p>We studied 588 individuals (59% males) aged 21 to 79 years. Liver steatosis was detected by ultrasonography and coded ordinally as none, intermediate and severe. 44% of the individuals had liver steatosis. Using proportional-odds ordinal logistic regression, we evaluated the ability of log-transformed LAP (lnLAP) to identify liver steatosis. We considered the benefits to our model of including terms for sex, age, suspected liver disease and ethanol intake. We calculated the 3-level probability of liver steatosis according to lnLAP and sex, providing tables and nomograms for risk assessment.</p> <p>Results</p> <p>An ordinal proportional-odds model consisting of lnLAP and sex offered a reasonably accurate identification of liver steatosis. The odds of more severe <it>vs. </it>less severe steatosis increased for increasing values of lnLAP (odds ratio [OR] = 4.28, 95%CI 3.28 to 5.58 for each log-unit increment) and was more likely among males (OR = 1.88, 95%CI 1.31 to 2.69).</p> <p>Conclusion</p> <p>In a study sample of adults from Northern Italy, the simple calculation of LAP was a reasonably accurate approach to recognizing individuals with ultrasonographic liver steatosis. LAP may help primary care physicians to select subjects for liver ultrasonography and intensified lifestyle counseling, and researchers to select patients for epidemiologic studies. A more thorough assessment of LAP's potential for identifying liver steatosis will require its cross-evaluation in external populations.</p

High field level crossing studies on spin dimers in the low dimensional quantum spin system Na2_2T2_2(C2_2O4_4)3_3(H2_2O)2_2 with T=Ni,Co,Fe,Mn

In this paper we demonstrate the application of high magnetic fields to study the magnetic properties of low dimensional spin systems. We present a case study on the series of 2-leg spin-ladder compounds Na$_2$T$_2$(C$_2$O$_4$)$_3$(H$_2$O)$_2$ with T = Ni, Co, Fe and Mn. In all compounds the transition metal is in the $T^{2+}$ high spin configuation. The localized spin varies from S=1 to 3/2, 2 and 5/2 within this series. The magnetic properties were examined experimentally by magnetic susceptibility, pulsed high field magnetization and specific heat measurements. The data are analysed using a spin hamiltonian description. Although the transition metal ions form structurally a 2-leg ladder, an isolated dimer model consistently describes the observations very well. This behaviour can be understood in terms of the different coordination and superexchange angles of the oxalate ligands along the rungs and legs of the 2-leg spin ladder. All compounds exhibit magnetic field driven ground state changes which at very low temperatures lead to a multistep behaviour in the magnetization curves. In the Co and Fe compounds a strong axial anisotropy induced by the orbital magnetism leads to a nearly degenerate ground state and a strongly reduced critical field. We find a monotonous decrease of the intradimer magnetic exchange if the spin quantum number is increased