Summer Ozone Concentrations in the Vicinity of the Great Salt Lake

Residents near the Great Salt Lake in northern Utah, USA have been exposed to ozone levels during recent summers exceeding the current United States National Ambient Air Quality Standard. Accurately forecasting those exceedances has been difficult as a result of the complex meteorological and photochemical processes fostering them. To help improve such forecasts, a low-cost field study was conducted during summer 2015 to provide comprehensive observations of boundary-layer ozone concentrations in the context of the prevailing meteorological conditions. A network of surface ozone sensors was supplemented by sensors mounted on vehicles, a public transit light-rail car, news helicopter, tethered sonde, and unmanned aerial vehicle. The temporal and spatial evolution of boundary-layer ozone concentrations were compared with the prevailing regional and local meteorological conditions on the basis of gridded operational analyses, surface weather stations, and additional sensors deployed for the field study. High ozone concentrations during June 2015 resulted primarily from local processes while smoke transported from distant wildfires contributed to elevated ozone concentrations during August. The Great Salt Lake influenced ozone concentrations along the Wasatch Front through several mechanisms, most importantly its impact on local wind circulations. The highest ozone concentrations were often found in a narrow zone between the Great Salt Lake and the urban regions to its south and east. Observations from multiple fixed site and mobile platforms during 18–19 August illustrate the complex variations in ozone concentrations as a function of elevation at the surface as well as vertically through the deep boundary layer

Systematic study of the 87^{87}Sr clock transition in an optical lattice

With ultracold $^{87}$Sr confined in a magic wavelength optical lattice, we present the most precise study (2.8 Hz statistical uncertainty) to-date of the $^1S_0$ - $^3P_0$ optical clock transition with a detailed analysis of systematic shifts (20 Hz uncertainty) in the absolute frequency measurement of 429 228 004 229 867 Hz. The high resolution permits an investigation of the optical lattice motional sideband structure. The local oscillator for this optical atomic clock is a stable diode laser with its Hz-level linewidth characterized across the optical spectrum using a femtosecond frequency comb.Comment: 4 pages, 4 figures, 1 tabl

The St. Lawrence polynya and the Bering shelf circulation : new observations and a model comparison

Author Posting. © American Geophysical Union, 2006. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Journal of Geophysical Research 111 (2006): C09023, doi:10.1029/2005JC003268.Using 14 year-long instrumented moorings deployed south of St. Lawrence Island, along with oceanographic drifters, we investigate the circulation over the central Bering shelf and the role of polynyas in forming and disseminating saline waters over the shelf. We focus also on evaluating the Gawarkiewicz and Chapman [1995] model of eddy production within coastal polynyas. Principal results include: 1) The northern central shelf near-surface waters exhibit westward flow carrying low-salinity waters from the Alaskan coast in fall and early winter, with consequences for water mass formation and biological production. 2) Within the St. Lawrence polynya, the freshening effect of winter advection is about half as large as the salting effect of surface brine flux resulting from freezing. 3) Brine production over the Bering shelf occurs primarily offshore, rather than within coastal polynyas, even though ice production per unit area is much larger within the polynyas. 4) We find little evidence for the geostrophic flow adjustment predicted by recent polynya models. 5) In contrast to the theoretical prediction that dense water from the polynya is carried offshore by eddies, we find negligible cross-shelf eddy density fluxes within and surrounding the polynya and very low levels of eddy energy that decreased from fall to winter, even though dense water accumulated within the polynya and large cross-shore density gradients developed. 6) It is possible that dense polynya water was advected downstream of our array before appreciable eddy fluxes materialized.This work was supported by National Science Foundation grant OCE9730697 to the University of Alaska and grant OCE9730823 to the University of Washington. S. M. acknowledges the support of the National Science Foundation under OCE9811097 and of NASA under grant NNG04GM69G. The University of Hamburg contributions were funded by the Bundesminister für Bildung und Wissenschaft. Funding for the drifter deployment was made possible by the North Pacific Research Board, grant NPMRI T2130. Manuscript preparation was additionally supported by Office of Naval Research grants N00014-99-1-0345 and N00014-02-1-0305 to the University of Washington

Clinical Characteristics of Patients Classified as Very High Risk and Not Very High Risk Based on the 2018 AHA/ACC Multi-Society Cholesterol Guideline

Background The 2018 AHA/ACC Cholesterol Guideline recommendation to classify ASCVD patients as very high-risk (VHR) vs not-VHR (NVHR) has important implications for ezetimibe and PCSK9 inhibitor eligibility. We aimed to define the clinical characteristics of these two groups within a large multi-state healthcare system in the Western U.S. Methods We performed a retrospective cohort analysis of patients defined as having ASCVD in 2018 using EHR ICD-10 codes. VHR was defined by ≥2 major ASCVD events (ACS ≤12 months, history of MI \u3e12 months, ischemic stroke, or symptomatic PAD) or 1 major ASCVD event and ≥2 high-risk conditions (age ≥65, DM, HTN, smoking, HeFH, CKD, CHF, persistently elevated LDL-C, or prior CABG/PCI). Patients not meeting these criteria were classified as NVHR. Results A total of 180,669 ASCVD patients were identified: 104,123 (58%) were VHR and 76,546 (42%) were NVHR. Mean age and gender was 70.1±13.4 years, 54% male and 73.1±11.9 years, 55% male for the NVHR and VHR groups, respectively. Among patients with a history of MI or recent ACS, 99% and 96% were classified as VHR, respectively (Table). Age ≥65, HTN and DM were the most prevalent high-risk conditions. Conclusion Criteria used to predict future CV risk largely divide ASCVD patients into groups of similar prevalence. Nearly all ACS/MI patients were VHR. With growing emphasis on individualized risk assessment and intense LDL-C reduction, opportunity exists to further refine risk prediction within these two at-risk groups

Lipoprotein sub-fractions by ion-mobility analysis and its association with subclinical coronary atherosclerosis in high-risk individuals

Aims: There is limited knowledge about the association of lipoprotein particles and markers of coronary atherosclerosis such as coronary artery calcification (CAC) in relatively young high-risk persons. This study examines the association of lipoprotein subfractions and CAC in high cardiometabolic risk individuals. Methods: The study presents analysis from baseline data of a randomized trial targeted at high-risk workers. Employees of Baptist Health South Florida with metabolic syndrome or diabetes were recruited. At baseline, all 182 participants had lipoprotein subfraction analysis using the ion mobility technique and participants above 35 years (N =170) had CAC test done. Principal components (PC) were computed for the combination of lipoprotein subclasses. Multiple bootstrapped regression analyses (BSA) were conducted to assess the relationship between lipoprotein subfractions and CAC. Results: The study population (N=170) was largely female (84%) with a mean age of 58 years. Three PCs accounted for 88% variation in the sample. PC2, with main contributions from VLDL particles in the positive direction and large LDL particles in the negative direction was associated with a 22% increase in CAC odds (P value ＜0.05 in 100% of BSA). PC3, with main contributions from HDL lipoprotein particles in the positive direction and small/medium LDL and large IDL particles in the negative direction, was associated with a 9% reduction in CAC odds (P＜0.05 in 88% of BSA). PC1, which had approximately even contributions from HDL, LDL, IDL and VLDL lipoprotein subfractions in the positive direction, was not associated with CAC. Conclusion: In a relatively young but high-risk population, a lipoprotein profile predominated by triglyceride-rich lipoproteins was associated with increased risk of CAC, while one predominated by HDL lipoproteins offered modest protection. Lipoprotein sub-fraction analysis may help to further discriminate patients who require more intensive cardiovascular work-up and treatment

Association of Lowering Low‐Density Lipoprotein Cholesterol With Contemporary Lipid‐Lowering Therapies and Risk of Diabetes Mellitus: A Systematic Review and Meta‐Analysis

Background The relationship between lowering LDL (low‐density lipoprotein) cholesterol with contemporary lipid‐lowering therapies and incident diabetes mellitus (DM) remains uncertain. Methods and Results Thirty‐three randomized controlled trials (21 of statins, 12 of PCSK9 [proprotein convertase subtilisin/kexin type 9] inhibitors, and 0 of ezetimibe) were selected using Medline, Embase, and the Cochrane Central Register of Controlled Trials (inception through November 15, 2018). A total of 163 688 nondiabetic patients were randomly assigned to more intensive (83 123 patients) or less intensive (80 565 patients) lipid‐lowering therapy. More intensive lipid‐lowering therapy was defined as the more potent pharmacological strategy (PCSK9 inhibitors, higher intensity statins, or statins), whereas less intensive therapy corresponded to active control group or placebo/usual care of the trial. Metaregression and meta‐analyses were conducted using a random‐effects model. No significant association was noted between 1‐mmol/L reduction in LDL cholesterol and incident DM for more intensive lipid‐lowering therapy (risk ratio: 0.95; 95% CI, 0.87–1.04; P=0.30; R2=14%) or for statins or PCSK9 inhibitors. More intensive lipid‐lowering therapy was associated with a higher risk of incident DM compared with less intensive therapy (risk ratio: 1.07; 95% CI, 1.03–1.11; P\u3c0.001; I2=0%). These results were driven by higher risk of incident DM with statins (risk ratio: 1.10; 95% CI, 1.05–1.15; P\u3c0.001; I2=0%), whereas PCSK9 inhibitors were not associated with incident DM (risk ratio: 1.00; 95% CI, 0.93–1.07; P=0.96; I2=0%; P=0.02 for interaction). Conclusions Among intensive lipid‐lowering therapies, there was no independent association between reduction in LDL cholesterol and incident DM. The risk of incident DM was higher with statins, whereas PCSK9 inhibitors had no association with risk of incident DM

Constraints on Low-Mass WIMP Interactions on 19F from PICASSO

Recent results from the PICASSO dark matter search experiment at SNOLAB are reported. These results were obtained using a subset of 10 detectors with a total target mass of 0.72 kg of 19F and an exposure of 114 kgd. The low backgrounds in PICASSO allow recoil energy thresholds as low as 1.7 keV to be obtained which results in an increased sensitivity to interactions from Weakly Interacting Massive Particles (WIMPs) with masses below 10 GeV/c^2. No dark matter signal was found. Best exclusion limits in the spin dependent sector were obtained for WIMP masses of 20 GeV/c^2 with a cross section on protons of sigma_p^SD = 0.032 pb (90% C.L.). In the spin independent sector close to the low mass region of 7 GeV/c2 favoured by CoGeNT and DAMA/LIBRA, cross sections larger than sigma_p^SI = 1.41x10^-4 pb (90% C.L.) are excluded.Comment: 23 pages, 7 figures, to be published in Phys. Lett.

Association of Lowering Low�Density Lipoprotein Cholesterol With Contemporary Lipid�Lowering Therapies and Risk of Diabetes Mellitus: A Systematic Review and Meta�Analysis

Background The relationship between lowering LDL (low�density lipoprotein) cholesterol with contemporary lipid�lowering therapies and incident diabetes mellitus (DM) remains uncertain. Methods and Results Thirty�three randomized controlled trials (21 of statins, 12 of PCSK9 [proprotein convertase subtilisin/kexin type 9] inhibitors, and 0 of ezetimibe) were selected using Medline, Embase, and the Cochrane Central Register of Controlled Trials (inception through November 15, 2018). A total of 163 688 nondiabetic patients were randomly assigned to more intensive (83 123 patients) or less intensive (80 565 patients) lipid�lowering therapy. More intensive lipid�lowering therapy was defined as the more potent pharmacological strategy (PCSK9 inhibitors, higher intensity statins, or statins), whereas less intensive therapy corresponded to active control group or placebo/usual care of the trial. Metaregression and meta�analyses were conducted using a random�effects model. No significant association was noted between 1�mmol/L reduction in LDL cholesterol and incident DM for more intensive lipid�lowering therapy (risk ratio: 0.95; 95% CI, 0.87–1.04; P=0.30; R2=14%) or for statins or PCSK9 inhibitors. More intensive lipid�lowering therapy was associated with a higher risk of incident DM compared with less intensive therapy (risk ratio: 1.07; 95% CI, 1.03–1.11; P<0.001; I2=0%). These results were driven by higher risk of incident DM with statins (risk ratio: 1.10; 95% CI, 1.05–1.15; P<0.001; I2=0%), whereas PCSK9 inhibitors were not associated with incident DM (risk ratio: 1.00; 95% CI, 0.93–1.07; P=0.96; I2=0%; P=0.02 for interaction). Conclusions Among intensive lipid�lowering therapies, there was no independent association between reduction in LDL cholesterol and incident DM. The risk of incident DM was higher with statins, whereas PCSK9 inhibitors had no association with risk of incident DM

Isotretinoin Use and the Risk of Inflammatory Bowel Disease: A Case–Control Study

Isotretinoin is commonly prescribed for the treatment of severe acne. Though cases of inflammatory bowel disease (IBD) have been reported in isotretinoin users, a causal association remains unproven

Inverse Relationship Between Moderate Alcohol Intake and Rectal Cancer: Analysis of the North Carolina Colon Cancer Study

The relationship between alcohol intake and rectal cancer is uncertai