Core excitation in Ozone localized to one of two symmetry-equivalent chemical bonds - molecular alignment through vibronic coupling

Core excitation from terminal oxygen O$_T$ in O$_3$ is shown to be an excitation from a localized core orbital to a localized valence orbital. The valence orbital is localized to one of the two equivalent chemical bonds. We experimentally demonstrate this with the Auger Doppler effect which is observable when O$_3$ is core-excited to the highly dissociative O$_{T}$1s$^{-1}$7a$_1^1$ state. Auger electrons emitted from the atomic oxygen fragment carry information about the molecular orientation relative to the electromagnetic field vector at the moment of excitation. The data together with analytical functions for the electron-peak profiles give clear evidence that the preferred molecular orientation for excitation only depends on the orientation of one bond, not on the total molecular orientation. The localization of the valence orbital "7a$_1$" is caused by mixing of the valence orbital "5b$_2$" through vibronic coupling of anti-symmetric stretching mode with b$_2$-symmetry. To the best of our knowledge, it is the first discussion of the localization of a core excitation of O$_3$. This result explains the success of the widely used assumption of localized core excitation in adsorbates and large molecules

Gender-specific associations of short sleep duration with prevalent and incident hypertension : the Whitehall II Study

Sleep deprivation (5 hour per night) was associated with a higher risk of hypertension in middle-aged American adults but not among older individuals. However, the outcome was based on self-reported diagnosis of incident hypertension, and no gender-specific analyses were included. We examined cross-sectional and prospective associations of sleep duration with prevalent and incident hypertension in a cohort of 10 308 British civil servants aged 35 to 55 years at baseline (phase 1: 1985-1988). Data were gathered from phase 5 (1997-1999) and phase 7 (2003-2004). Sleep duration and other covariates were assessed at phase 5. At both examinations, hypertension was defined as blood pressure 140/90 mm Hg or regular use of antihypertensive medications. In cross-sectional analyses at phase 5 (n5766), short duration of sleep (5 hour per night) was associated with higher risk of hypertension compared with the group sleeping 7 hours, among women (odds ratio: 2.01; 95% CI: 1.13 to 3.58), independent of confounders, with an inverse linear trend across decreasing hours of sleep (P0.003). No association was detected in men. In prospective analyses (mean follow-up: 5 years), the cumulative incidence of hypertension was 20.0% (n740) among 3691 normotensive individuals at phase 5. In women, short duration of sleep was associated with a higher risk of hypertension in a reduced model (age and employment) (6 hours per night: odds ratio: 1.56 [95% CI: 1.07 to 2.27]; 5 hour per night: odds ratio: 1.94 [95% CI: 1.08 to 3.50] versus 7 hours). The associations were attenuated after accounting for cardiovascular risk factors and psychiatric comorbidities (odds ratio: 1.42 [95% CI: 0.94 to 2.16]; odds ratio: 1.31 [95% CI: 0.65 to 2.63], respectively). Sleep deprivation may produce detrimental cardiovascular effects among women. (Hypertension. 2007;50:694-701.) Key Words: sleep duration blood pressure hypertension gender differences confounders comorbiditie

Double photoionization of propylene oxide: a coincidence study of the ejection of a pair of valence-shell electrons

Propylene oxide, a favorite target of experimental and theoretical studies of circular dichroism, was recently discovered in interstellar space, further amplifying the attention to its role in the current debate on protobiological homochirality. In the present work, a photoelectron-photoion-photoion coincidence technique, using an ion-imaging detector and tunable synchrotron radiation in the 18.0-37.0 eV energy range, permits us (i) to observe six double ionization fragmentation channels, their relative yields being accounted for about two-thirds by the couple (C2H4+, CH2O+) and one-fifth by (C2H3+, CH3O+); (ii) to measure thresholds for their openings as a function of photon energy; and (iii) to unravel a pronounced bimodality for a kinetic-energy-released distribution, fingerprint of competitive non-adiabatic mechanisms

Prevalence of Hypertension in Low- and Middle-Income Countries: A Systematic Review and Meta-Analysis.

We aimed to obtain overall and regional estimates of hypertension prevalence, and to examine the pattern of this disease condition across different socio-demographic characteristics in low-and middle-income countries. We searched electronic databases from inception to August 2015. We included population-based studies that reported hypertension prevalence using the current definition of blood pressure ≥140/90 mm Hg or self-reported use of antihypertensive medication. We used random-effects meta-analyses to pool prevalence estimates of hypertension, overall, by World Bank region and country income group. Meta-regression analyses were performed to explore sources of heterogeneity across the included studies. A total of 242 studies, comprising data on 1,494,609 adults from 45 countries, met our inclusion criteria. The overall prevalence of hypertension was 32.3% (95% confidence interval [CI] 29.4-35.3), with the Latin America and Caribbean region reporting the highest estimates (39.1%, 95% CI 33.1-45.2). Pooled prevalence estimate was also highest across upper middle income countries (37.8%, 95% CI 35.0-40.6) and lowest across low-income countries (23.1%, 95% CI 20.1-26.2). Prevalence estimates were significantly higher in the elderly (≥65 years) compared with younger adults (\u3c65 \u3eyears) overall and across the geographical regions; however, there was no significant sex-difference in hypertension prevalence (31.9% vs 30.8%, P = 0.6). Persons without formal education (49.0% vs 24.9%, P \u3c 0.00001), overweight/obese (46.4% vs 26.3%, P \u3c 0.00001), and urban settlers (32.7% vs 25.2%, P = 0.0005) were also more likely to be hypertensive, compared with those who were educated, normal weight, and rural settlers respectively. This study provides contemporary and up-to-date estimates that reflect the significant burden of hypertension in low- and middle-income countries, as well as evidence that hypertension remains a major public health issue across the various socio-demographic subgroups. On average, about 1 in 3 adults in the developing world is hypertensive. The findings of this study will be useful for the design of hypertension screening and treatment programmes in low- and middle-income countries

Examining the correlates of adolescent food and nutrition knowledge

Food literacy is a set of skills and knowledge that are integral to diet. It is common among teenagers to not have basic food literacy skills needed to consume a healthy diet. This study examined: (1) the current state of food and nutrition knowledge among adolescents 13–19 years of age in the census metropolitan area of London, ON, Canada; and (2) correlates of food knowledge and nutrition knowledge among adolescents. Data for this study were drawn from baseline youth and parent survey data collected from a larger population health intervention study. Statistical analysis of the survey data indicates that higher parental education and higher median neighbourhood family income, the use of mobile health applications, liking to cook, as well as confidence in reading and understanding food labels were all consistently associated with increased food and nutrition knowledge. Findings may help guide future research towards optimal methods for delivering food literacy interventions to effectively educate teenagers. Results of this study may help guide policy makers, researchers, and public health professionals in developing appropriate food and nutrition programs and curriculums to combat the decline in food literacy skills

Real-time dynamics of the formation of hydrated electrons upon irradiation of water clusters with extreme ultraviolet light

Free electrons in a polar liquid can form a bound state via interaction with the molecular environment. This so-called hydrated electron state in water is of fundamental importance e.g.~in cellular biology or radiation chemistry. Hydrated electrons are highly reactive radicals that can either directly interact with DNA or enzymes, or form highly excited hydrogen (H∗) after being captured by protons. Here, we investigate the formation of the hydrated electron in real-time employing XUV femtosecond pulses from a free electron laser, in this way observing the initial steps of the hydration process. Using time-resolved photoelectron spectroscopy we find formation timescales in the low picosecond range and resolve the prominent dynamics of forming excited hydrogen states

Collective Autoionization in Multiply-Excited Systems: A novel ionization process observed in Helium Nanodroplets

Free electron lasers (FELs) offer the unprecedented capability to study reaction dynamics and image the structure of complex systems. When multiple photons are absorbed in complex systems, a plasma-like state is formed where many atoms are ionized on a femtosecond timescale. If multiphoton absorption is resonantly-enhanced, the system becomes electronically-excited prior to plasma formation, with subsequent decay paths which have been scarcely investigated to date. Here, we show using helium nanodroplets as an example that these systems can decay by a new type of process, named collective autoionization. In addition, we show that this process is surprisingly efficient, leading to ion abundances much greater than that of direct single-photon ionization. This novel collective ionization process is expected to be important in many other complex systems, e.g. macromolecules and nanoparticles, exposed to high intensity radiation fields