Zirconia-supported tungsten oxide (WO(x)/ZrO(2)) is considered an important supported metal oxide model acid catalyst, for which structure-property relationships have been studied for numerous acid-catalyzed reactions. The catalytic activity for xylene isomerization, alcohol dehydration, and aromatic acylation follows a volcano-shape dependence on tungsten surface density. However, WO(x)/ZrO(2) has not been studied for more acid-demanding reactions, like n-pentane isomerization, with regard to surface density dependence. In this work, WO(x)/ZrO(2) was synthesized using commercially available amorphous ZrO(x)(OH)(4-2x) and model crystalline ZrO(2) as support precursors. They were analyzed for n-pentane isomerization activity and selectivity as a function of tungsten surface density, catalyst support type, and calcination temperature. Amorphous ZrO(x)(OH)(4-2x) led to WO(x)/ZrO(2) (WZrOH) that exhibited maximum isomerization activity at ∼5.2 W·nm(-2), and the crystalline ZrO(2) led to a material (WZrO(2)) nearly inactive at all surface densities. Increasing the calcination temperature from 773 to 973 K increased the formation of 0.8-1 nm Zr-WO(x) clusters detected through direct imaging on an aberration-corrected high-resolution scanning transmission electron microscope (STEM). Calcination temperature further increased catalytic activity by at least two times. Brønsted acidity was not affected but Lewis acidity decreased in number, as quantified via pyridine adsorption infrared spectroscopy. WO(x)/ZrO(2) exhibited isomerization activity that peaked within the first 2 h time-on-stream, which may be due to Zr-WO(x) clusters undergoing an activation process.
More than half of youth requiring ED care had not previously sought outpatient MH care. Associations with multiple markers of primary care access characteristics suggest that timely primary care could prevent some of these visits.
Despite its widespread influences on the atmosphere, the Madden‐Julian oscillation (MJO) remains poorly represented in state‐of‐the‐art general circulation models (GCMs). Motivated by recent findings that the horizontal advection of the mean low‐tropospheric moist static energy or moisture by the MJO winds plays a crucial role in the eastward propagation of the MJO, we investigate the relationship between lower tropospheric moisture patterns over the Indo‐Pacific and MJO eastward propagation in a suite of 23 GCM simulations. Model capability of reproducing the observed November–April mean lower tropospheric moisture pattern over the Indo‐Pacific, especially near the Maritime Continent (MC), is highly correlated with model skill in simulating MJO eastward propagation. In GCMs with difficulty capturing realistic MJO propagation, the amplitude of the mean low‐level moisture over the MC is greatly underestimated, leading to weak horizontal moisture gradients and thus discrepancies in moisture advection, significantly affecting MJO propagation. This study suggests that the mean lower tropospheric moisture pattern over the MC can serve as an important diagnostic metric for MJO propagation in climate models.
Background:We aimed to define rates and causes of death in custody and after release in people admitted to provincial custody in Ontario, and to compare these data with data for the general population. Methods:We linked data on adults admitted to provincial custody in Ontario in 2000 with data on deaths between 2000 and 2012. We examined rates and causes of death by age, sex, custodial status and period after release, and compared them with data for the general population, using indirect adjustment for age.Results: Between 2000 and 2012, 8.6% (95% confidence interval [CI] 8.3%-8.8%) of those incarcerated died in provincial custody or after release. The crude death rate was 7.1 (95% CI 6.9-7.3) per 1000 person-years. The standardized mortality ratio for those incarcerated in 2000 was 4.0 (95% CI 3.9-4.1) overall and 1.9 (95% CI 1.5-2.4) while in provincial custody. The most common causes of death were injury and poisoning (38.2% of all deaths), including overdose (13.6%) and suicide (8.2%), diseases of the circulatory system (15.8%) and neoplasms (14.5%). In the 2 weeks after release, the standardized mortality ratio was 5.7 overall and 56.0 for overdose. Life expectancy was 72.3 years for women and 73.4 for men who experienced incarceration in 2000. Interpretation:Mortality was high for people who experienced incarceration, and life expectancy was 4.2 years less for men and 10.6 years less for women compared with the general population. Efforts should be made to reduce the gap in mortality between people who experience incarceration and those who do not. Time in custody could serve as an opportunity to intervene to decrease risk. Abstract Research CMAJ OPEN E154CMAJ OPEN, 4(2) sentenced) or incarcerated (i.e., sentenced); in this article we use the term incarcerated to represent both of these groups.
Particular intestinal bacteria are capable of metabolizing the soya isoflavone daidzein to equol and/or O-desmethylangolensin (O-DMA), and the presence of these metabolites in urine after soya consumption are markers of particular intestinal bacteria profiles. Prevalences of equol producers and O-DMA producers are approximately 30-50 % and 80-90 %, respectively, and limited observations have suggested that these daidzein-metabolizing phenotypes are stable within individuals over time. Characterizing stability of these phenotypes is important to understand their potential as markers of long-term exposure to particular intestinal bacteria and their associations with disease risk. We evaluated concordance within an individual for the equol-producer and O-DMA-producer phenotypes measured at two time points (T1, T2), 1 -3 years apart. Phenotypes were ascertained by analysing equol and O-DMA using GC-MS in a spot urine sample collected after 3 d soya (source of daidzein) supplementation. In ninety-two individuals without recent (within 3 months before phenotyping) or current antibiotics use, 41 % were equol producers at T1 and 45 % were equol producers at T2, and 90 % were O-DMA producers at T1 and 95 % were O-DMA producers at T2. The percentage agreement for the equol-producer phenotype was 82 and for the O-DMA-producer phenotype was 89. These results indicate that these phenotypes are stable in most individuals over time, suggesting that they provide a useful biomarker for evaluating disease risk associated with harbouring particular intestinal bacteria responsible for, or associated with, the metabolism of the soya isoflavone daidzein. Equol: O-Desmethylangolensin: Soya: DaidzeinThe soya isoflavone daidzein is metabolized to equol and O-desmethylangolensin (O-DMA) by particular intestinal bacteria. Although the specific bacteria responsible have not yet been definitively identified, there are several lines of evidence from in vitro and animal studies to indicate that intestinal bacteria, and not endogenous host metabolism, are responsible for this conversion (Chang & Nair, 1995;Blair et al. 2003;Bowey et al. 2003;Atkinson et al. 2004). For example, it has been observed that, in vitro, microbiota in faeces from equol producers can convert daidzein to equol, whereas microbiota from non-producers does not (Chang & Nair, 1995;Atkinson et al. 2004) and in vivo, that germ-free animals do not produce equol (Bowey et al. 1976;Lombardi et al. 1978;Järvenpää et al. 1980), the variability in bacterial daidzein metabolism may be associated with hormone-related disease risk; we review this in detail elsewhere (Atkinson et al. 2005).Observations from a study of Japanese men suggest that these daidzein-metabolizing phenotypes are stable in individuals over time. In forty men, 85 % retained their equol-producer phenotype when measured at two time points approximately 1·5 years apart (Akaza et al.
Particular intestinal bacteria metabolize the soy isoflavone daidzein to equol and O-desmethylangolensin (O-DMA), metabolites that can be identified in urine. Individuals that harbor bacteria capable of producing equol or O-DMA are known as equol producers (approximately 30%-50% of the population) and O-DMA producers (approximately 80%-90% of the population), respectively. The equol-producer phenotype has been associated with sex hormone-related outcomes in several studies. However, the bacteria responsible for these phenotypes have not yet been identified and factors that influence the manifestation of these phenotypes are not well understood. To evaluate familial clustering of and nongenetic factors associated with these phenotypes, 410 individuals from 112 families participated in phenotyping (3-day soy challenge and Day 4 spot urine collection). In segregation analyses of the equol-producer phenotype, the Mendelian dominant model provided the most parsimonious fit to the data, suggesting that the pattern of inheritance of the equol-producer phenotype is consistent with an autosomal dominant trait. This phenotype was positively associated with education (p trend = 0.01), but not with sex, smoking, or several dietary factors. Results of the segregation analyses of the O-DMA-producer phenotype were inconclusive; no other models provided a more parsimonious fit to the data than the general model. This phenotype was inversely associated with age in a nonlinear model (p = 0.01), positively associated with age- and sex-adjusted height (odds ratio [OR] 10-cm increase = 0.38, 95% confidence interval [CI] = 0.15, 0.95) and body mass index (kg/m(2)) (OR = 0.91, 95% CI = 0.85, 0.96), but not with sex, education, smoking, or several dietary factors. These results suggest the equol-producer phenotype may be under some degree of genetic control and that there are likely other environmental factors not evaluated in the present analysis that contribute to both of these phenotypes. These results provide a foundation for further work to refine our understanding of heritable and environmental determinants of daidzein-metabolizing phenotypes.
Introduction Laboratory and animal studies suggest a beneficial effect of zinc on prostate cancer. Methods We evaluated the association between dietary and supplemental zinc and prostate cancer within the VITamins And Lifestyle (VITAL) cohort, a study specifically designed to evaluate the impact of dietary supplements and cancer risk. Of 35,242 men who completed the baseline dietary and supplemental questionnaire, 832 men developed invasive prostate cancers between October 2000 and December 2004. Results Ten-year average intake of supplemental zinc was not associated with a reduced prostate cancer risk overall (adjusted hazard ratio (HR) = 0.82 (95% confidence interval (CI) 0.58-1.14) for >15mg/day versus non-use, p for trend = 0.44); however, risk of advanced prostate cancer (regionally invasive or distant metastatic, n=123) decreased with greater intake of supplemental zinc (adjusted HR = 0.34 (95% CI 0.13-1.09) for 10-year average intake >15mg/day vs. non-use, p for trend = 0.04). Dietary zinc was not associated with prostate cancer. Discussion In this prospective cohort, long-term supplemental zinc intake was associated with reduced risk of clinically relevant advanced disease. This study had limited ability to study early stage disease, because detection of early stage disease is highly related to having a PSA test, and information on PSA was only available at baseline. Because few other epidemiologic studies have investigated the association between zinc and prostate cancer and these have not yielded consistent findings, further research is needed.
Tropical intraseasonal variability, with the Madden‐Julian oscillation (MJO) as its most prominent mode, exerts extensive influences on global weather extremes. It is found that strong interannual variability of intraseasonal convection exists in the west Pacific (WP), in the form of years with strong eastward propagation (i.e., associated with the MJO) and years with strong westward propagation. Years with strong westward propagation on intraseasonal timescales are dominated by a westward propagating intraseasonal mode (WPIM), which is the second leading intraseasonal mode after the MJO over the tropical WP. Initiated over the central Pacific, the WPIM exhibits slow equatorial westward propagation (5 m/s) with a period of 25 days and a spatial scale of zonal wave number 3–4. Unlike the MJO, the WPIM lacks a significant tilt with height in specific humidity and vertical velocity. A strong anticorrelation is found between MJO and WPIM activity on interannual timescales over the WP. Budget analyses of the moist static energy suggest that both modes are driven by horizontal moist static energy advection and that substantial differences in winter mean large‐scale moisture and zonal winds largely define their distinct propagation behaviors. The WPIM is favored, while the MJO is suppressed when mean equatorial low‐level easterlies between 150°E and 160°W are enhanced and equatorial mean low‐level moisture is reduced near the Dateline and enhanced in the off‐equatorial WP (110°–150°E). While the WPIM bears resemblance to low‐frequency equatorial Rossby waves, a more detailed analysis must be conducted to affirm if they are the same phenomenon.
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