Optically Stimulated Luminescence Dating of Late Holocene Raised Strandplain Sequences Adjacent to Lakes Michigan and Superior, Upper Peninsula, Michigan, USA

This study evaluates the accuracy of optically stimulated luminescence to date well-preserved strandline sequences at Manistique/ Thompson bay (Lake Michigan), and Tahquamenon and Grand Traverse Bays (Lake Superior) that span the past ~4500 yr. The single aliquot regeneration (SAR) method is applied to produce absolute ages for littoral and eolian sediments. SAR ages are compared against AMS and conventional 14C ages on swale organics. Modern littoral and eolian sediments yield SAR ages b100 yr indicating near, if not complete, solar resetting of luminescence prior to deposition. Beach ridges that yield SAR ages b2000 yr show general agreement with corresponding 14C ages on swale organics. Significant variability in 14C ages N2000 cal yr B.P. complicates comparison to SAR ages at all sites. However, a SAR age of 4280 F 390 yr (UIC913) on ridge77 at Tahquamenon Bay is consistent with regional regression from the high lake level of the Nipissing II phase ca. 4500 cal yr B.P. SAR ages indicate a decrease in ridge formation rate after ~1500 yr ago, likely reflecting separation of Lake Superior from lakes Huron and Michigan. This study shows that SAR is a credible alternative to 14C methods for dating littoral and eolian landforms in Great Lakes and other coastal strandplains where 14C methods prove problematic. D 2004 University of Washington. All rights reserved

923-3 Fluosol Reduces Myocardial Reperfusion Injury by Prolonged Suppression of Neutrophils by its Detergent Component (RheothRx) and not by Enhancing O2Delivery

Fluosol, a complex mixture of O2carrying perfluorocarbons (PFCs) emulsified by the detergent pluronic F-68 and a variety of lipids, significantly reduces myocardial reperfusion injury (RI) in animals and humans as shown in some initial clinical trials. Potential mechanisms for Fluosol include enhanced O2delivery to the reperfused tissue and modulation of various neutrophil (PMNs) functions. Recent studies in dogs and man demonstrate the same beneficial effect for treatment of Rl with the detergent component alone, RheothRx, which is currently undergoing clinical trials. We have shown that the effect of Fluosol on PMNs is related to this detergent. However, prolonged infusion (48 hrs) of detergent is required to reduce Rl to the same extent as Fluosol given over only 1 hr. Possible mechanisms for the beneficial effects of Fluosol (O2delivery vs effects on PMNs) were investigated in a model of regional ischemia utilizing rabbits undergoing 30mins of circumflex occlusion and 48 hrs of reperfusion. Infarct size (area of necrosis, AN) was determined histologically and expressed as percent of risk region (area at risk, AR). Animals received Fluosol (30cc/kg) with or without O2or saline over the first 60mins of reperfusion. AR was similar in all groups. (Mean±SEM of AN/AR (%), n=11 for all groups). The treatment with Fluosol with or without O2(44±3 and 40;±3, respectively) was significantly (p<0.05) reduced compared to control (63±4). Another group received F-I08, a larger size pluronic detergent found to be 2.5-fold more potent in suppressing PMN function in vitrocompared to F-68, during the first 3 hrs of reperfusion. This treatment did not alter the infarct size (63±5). RheothRx was found to form 4 nm micelles in solution whereas Fluosol formed particles approximately 100 times larger. Similar sized particles were formed by substituting the perfluorocarbons with mineral oil. The in vitroactivity of this pluronic/mineral oil micelle on PMN function was similar to Fluosol. Infusion of these larger oil micelles was tolerated by rabbits and used in further infarct studies.ConclusionsThese studies suggest that (1) reduction of RI by Fluosol is not due to enhanced O2delivery by the PFCs to reperfused myocardium and (2) since the Fluosol emulsion markedly reduces the clearance of the detergent F-68 (t½: Fluosol ≅ 8 hrs vs RheothRx ≅ 1.5 hrs). prolonged PMN suppression rather than potency of suppression is the mechanism whereby Fluosol ameliorates RI. Fluosol's clinical efficacy may be enhanced by prolonging its infusion to ensure an adequate blood level to suppress PMN function beyond the time of reperfusion injury. RheothRx's clinical usefulness may be facilitated by decreasing its renal clearance by delivering larger micelles of the detergent in order to produce prolonged PMN suppression with a shorter infusion time

A Deep Chandra Observation of the Distant Galaxy Cluster MS1137.5+6625

We present results from a deep Chandra observation of MS1137.5+66, a distant (z=0.783) and massive cluster of galaxies. Only a few similarly massive clusters are currently known at such high redshifts; accordingly, this observation provides much-needed information on the dynamical state of these rare systems. The cluster appears both regular and symmetric in the X-ray image. However, our analysis of the spectral and spatial X-ray data in conjunction with interferometric Sunyaev-Zel'dovich effect data and published deep optical imaging suggests the cluster has a fairly complex structure. The angular diameter distance we calculate from the Chandra and Sunyaev-Zel'dovich effect data assuming an isothermal, spherically symmetric cluster implies a low value for the Hubble constant for which we explore possible explanations.Comment: 16 pages, 6 figures, submitted to Ap

Near-Infrared Synchrotron Emission from Cas A

High energy observations of Cas A suggested the presence of synchrotron radiation, implying acceleration of cosmic rays by young supernova remnants. We detect synchrotron emission from Cas A in the near-infrared using Two Micron All Sky Survey (2MASS) and Palomar 200 inch PFIRCAM observations. The remnant is detected in J, H, and Ks bands, with Ks band brightest and J faint. In the J and H bands, bright [Fe II] lines (1.24um and 1.64um) are detected spectroscopically. The Palomar observations include Ks continuum, narrow-band 1.64um (centered on [Fe II]) and 2.12um (centered on H2(1-0)) images. While the narrow-band 1.64um image shows filamentary and knotty structures, similar to the optical image, the Ks image shows a relatively smooth, diffuse shell, remarkably similar to the radio image. The broad-band near-infrared fluxes of Cas A are generally consistent with, but a few tens of percent higher than, an extrapolation of the radio fluxes. The hardening to higher frequencies is possibly due to nonlinear shock acceleration and/or spectral index variation across the remnant. We show evidence of spectral index variation. The presence of near-infrared synchrotron radiation requires the roll-off frequency to be higher than 1.5e14 Hz, implying that electrons are accelerated to energies of at least 0.2 TeV. The morphological similarity in diffuse emission between the radio and Ks band images implies that synchrotron losses are not dominant. Our observations show unambiguous evidence that the near-infrared Ks band emission of Cas A is from synchrotron emission by accelerated cosmic-ray electrons.Comment: accepted by Ap

Genetic Predisposition to High Blood Pressure Associates With Cardiovascular Complications Among Patients With Type 2 Diabetes: Two Independent Studies

Hypertension and type 2 diabetes (T2D) commonly coexist, and both conditions are major risk factors for cardiovascular disease (CVD). We aimed to examine the association between genetic predisposition to high blood pressure and risk of CVD in individuals with T2D. The current study included 1,005 men and 1,299 women with T2D from the Health Professionals Follow-up Study and Nurses’ Health Study, of whom 732 developed CVD. A genetic predisposition score was calculated on the basis of 29 established blood pressure–associated variants. The genetic predisposition score showed consistent associations with risk of CVD in men and women. In the combined results, each additional blood pressure–increasing allele was associated with a 6% increased risk of CVD (odds ratio [OR] 1.06 [95% CI 1.03–1.10]). The OR was 1.62 (1.22–2.14) for risk of CVD comparing the extreme quartiles of the genetic predisposition score. The genetic association for CVD risk was significantly stronger in patients with T2D than that estimated in the general populations by a meta-analysis (OR per SD of genetic score 1.22 [95% CI 1.10–1.35] vs. 1.10 [1.08–1.12]; I2 = 71%). Our data indicate that genetic predisposition to high blood pressure is associated with an increased risk of CVD in individuals with T2D

Predictions for the X-ray circumgalactic medium of edge-on discs and spheroids

We investigate how the X-ray circumgalactic medium (CGM) of present-day galaxies depends on galaxy morphology and azimuthal angle using mock observations generated from the EAGLE cosmological hydrodynamic simulation. By creating mock stacks of {\it eROSITA}-observed galaxies oriented to be edge-on, we make several observationally-testable predictions for galaxies in the stellar mass range $M_\star=10^{10.7-11.2}\;$M$_{\odot}$. The soft X-ray CGM of disc galaxies is between 60 and 100\% brighter along the semi-major axis compared to the semi-minor axis, between 10-30 kpc. This azimuthal dependence is a consequence of the hot ($T>10^6$ K) CGM being non-spherical: specifically it is flattened along the minor axis such that denser and more luminous gas resides in the disc plane and co-rotates with the galaxy. Outflows enrich and heat the CGM preferentially perpendicular to the disc, but we do not find an observationally-detectable signature along the semi-minor axis. Spheroidal galaxies have hotter CGMs than disc galaxies related to spheroids residing at higher halos masses, which may be measurable through hardness ratios spanning the $0.2-1.5$ keV band. While spheroids appear to have brighter CGMs than discs for the selected fixed $M_\star$ bin, this owes to spheroids having higher stellar and halo masses within that $M_\star$ bin, and obscures the fact that both simulated populations have similar total CGM luminosities at the exact same $M_\star$. Discs have brighter emission inside 20 kpc and more steeply declining profiles with radius than spheroids. We predict that the {\it eROSITA} 4-year all-sky survey should detect many of the signatures we predict here, although targeted follow-up observations of highly inclined nearby discs after the survey may be necessary to observe some of our azimuthally-dependent predictions.Comment: 12 pages, 11 figures, 1 table. Submitted to MNRAS. Comments welcom

Dietary fiber intake and mortality among survivors of myocardial infarction: prospective cohort study

Objective: To evaluate the associations of dietary fiber after myocardial infarction (MI) and changes in dietary fiber intake from before to after MI with all cause and cardiovascular mortality. Design: Prospective cohort study. Setting: Two large prospective cohort studies of US women and men with repeated dietary measurements: the Nurses’ Health Study and the Health Professionals Follow-Up Study. Participants: 2258 women and 1840 men who were free of cardiovascular disease, stroke, or cancer at enrollment, survived a first MI during follow-up, were free of stroke at the time of initial onset of MI, and provided food frequency questionnaires pre-MI and at least one post-MI. Main outcome measures Associations of dietary fiber post-MI and changes from before to after MI with all cause and cardiovascular mortality using Cox proportional hazards models, adjusting for drug use, medical history, and lifestyle factors. Results: Higher post-MI fiber intake was significantly associated with lower all cause mortality (comparing extreme fifths, pooled hazard ratio 0.75, 95% confidence interval 0.58 to 0.97). Greater intake of cereal fiber was more strongly associated with all cause mortality (pooled hazard ratio 0.73, 0.58 to 0.91) than were other sources of dietary fiber. Increased fiber intake from before to after MI was significantly associated with lower all cause mortality (pooled hazard ratio 0.69, 0.55 to 0.87). Conclusions: In this prospective study of patients who survived MI, a greater intake of dietary fiber after MI, especially cereal fiber, was inversely associated with all cause mortality. In addition, increasing consumption of fiber from before to after MI was significantly associated with lower all cause and cardiovascular mortality

Gas sloshing regulates and records the evolution of the Fornax Cluster

We present results of a joint Chandra and XMM-Newton analysis of the Fornax Cluster, the nearest galaxy cluster in the southern sky. Signatures of merger-induced gas sloshing can be seen in the X-ray image. We identify four sloshing cold fronts in the intracluster medium, residing at radii of 3 kpc (west), 10 kpc (northeast), 30 kpc (southwest), and 200 kpc (east). Despite spanning over two orders of magnitude in radius, all four cold fronts fall onto the same spiral pattern that wraps around the BCG NGC 1399, likely all initiated by the infall of NGC 1404. The most evident front is to the northeast, 10 kpc from the cluster center, which separates low-entropy high-metallicity gas and high-entropy low-metallicity gas. The metallicity map suggests that gas sloshing, rather than an AGN outburst, is the driving force behind the redistribution of the enriched gas in this cluster. The innermost cold front resides within the radius of the strong cool core. The sloshing timescale within the cooling radius, calculated from the Brunt–Väsälä frequency, is an order of magnitude shorter than the cooling time. It is plausible that gas sloshing is contributing to the heating of the cool core, provided that gas of different entropies can be mixed effectively via Kelvin–Helmholtz instability. The estimated age of the outermost front suggests that this is not the first infall of NGC 1404

Diabetes and lipid screening among patients in primary care: A cohort study

<p>Abstract</p> <p>Background</p> <p>Obesity is associated with increased cardiovascular diseases and diabetes mellitus. Guidelines call for intensified glucose and lipid screening among overweight and obese patients. Data on compliance with these guidelines are scarce. The purpose of this study was to assess rates of diabetes and lipid screening in primary care according to demographic variables and weight status.</p> <p>Methods</p> <p>Over a 3-year follow-up period, we assessed screening rates for blood glucose, triglycerides, and HDL- and LDL-cholesterol among 5025 patients in primary care. From proportional hazards models we estimated screening rates among low, moderate, high, and very-high risk patients and compared them with recommendations of the American Diabetes Association (ADA), National Cholesterol Education Program (ATP III) and U.S. Preventive Services Task Force (USPSTF).</p> <p>Results</p> <p>Mean (SD) age was 47.4 (15.6); 69% were female, 21% were non-white, and 30% of males and 25% of females were obese (BMI ≥ 30 kg/m²). For both diabetes and lipid screening, the adjusted hazard was 260–330% higher among ≥65 than <35 year-olds, 50–90% higher in persons with BMI ≥ 35 than <25 kg/m², 10–30% lower for females than males, and not lower among racial/ethnic minorities. Screening rates were at least 80% among very-high risk persons, which we defined as 55–64 years old, BMI ≥ 35 kg/m², non-white, with baseline hypertension. In contrast, high-risk persons who were younger (35–44 years old) and less obese (BMI 30–<35 kg/m²) were screened less often (43% for LDL-cholesterol among females to 83% for diabetes among males) even though ADA, ATP III and USPSTF recommend diabetes and lipid screening among them.</p> <p>Conclusion</p> <p>Patients with higher BMI or age were more likely to be screened for cardiometabolic risk factors. Women were screened at lower rates than men. Even in a highly structured medical group practice, some obese patients were under-screened for diabetes and dyslipidemia.</p