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Reactions of the hydrated electron with a wide variety of substrates have been found to exhibit unusually similar activation energies in a manner incompatible with Marcus electron transfer theory. Given the fundamental linear response assumption of Marcus theory, one possible explanation for this apparent failure is that the underlying free energy surfaces governing the reactions are not harmonic; i.e., hydrated electron structural fluctuations exhibit non-Gaussian behavior. In this work, we test this hypothesis by using simulations to calculate the hydrated electron vertical detachment energy distribution. We consider both cavity and noncavity models for the hydrated electron, between which the actual hydrated electron behavior is expected to lie. Our results identify a possible origin for non-Gaussian behavior of the hydrated electron but show that it is not of sufficient magnitude to explain the failure of Marcus theory to describe its reactions. Thus, other explanations must be sought.

Pulse radiolysis with a custom multichannel detection system has been used to measure the kinetics of the radiation chemistry reactions of aqueous solutions of chromium(VI) to 325 °C for the first time. Kinetic traces were measured simultaneously over a range of wavelengths and fit to obtain the associated high-temperature rate coefficients and Arrhenius parameters for the reactions of Cr(VI) +

International audience; BACKGROUND: Reliable and timely information on the leading causes of death in populations, and how these are changing, is a crucial input into health policy debates. In the Global Burden of Diseases, Injuries, and Risk Factors Study 2010 (GBD 2010), we aimed to estimate annual deaths for the world and 21 regions between 1980 and 2010 for 235 causes, with uncertainty intervals (UIs), separately by age and sex. METHODS: We attempted to identify all available data on causes of death for 187 countries from 1980 to 2010 from vital registration, verbal autopsy, mortality surveillance, censuses, surveys, hospitals, police records, and mortuaries. We assessed data quality for completeness, diagnostic accuracy, missing data, stochastic variations, and probable causes of death. We applied six different modelling strategies to estimate cause-specific mortality trends depending on the strength of the data. For 133 causes and three special aggregates we used the Cause of Death Ensemble model (CODEm) approach, which uses four families of statistical models testing a large set of different models using different permutations of covariates. Model ensembles were developed from these component models. We assessed model performance with rigorous out-of-sample testing of prediction error and the validity of 95% UIs. For 13 causes with low observed numbers of deaths, we developed negative binomial models with plausible covariates. For 27 causes for which death is rare, we modelled the higher level cause in the cause hierarchy of the GBD 2010 and then allocated deaths across component causes proportionately, estimated from all available data in the database. For selected causes (African trypanosomiasis, congenital syphilis, whooping cough, measles, typhoid and parathyroid, leishmaniasis, acute hepatitis E, and HIV/AIDS), we used natural history models based on information on incidence, prevalence, and case-fatality. We separately estimated cause fractions by aetiology for diarrhoea, lower respiratory infections, and meningitis, as well as disaggregations by subcause for chronic kidney disease, maternal disorders, cirrhosis, and liver cancer. For deaths due to collective violence and natural disasters, we used mortality shock regressions. For every cause, we estimated 95% UIs that captured both parameter estimation uncertainty and uncertainty due to model specification where CODEm was used. We constrained cause-specific fractions within every age-sex group to sum to total mortality based on draws from the uncertainty distributions. FINDINGS: In 2010, there were 52*8 million deaths globally. At the most aggregate level, communicable, maternal, neonatal, and nutritional causes were 24*9% of deaths worldwide in 2010, down from 15*9 million (34*1%) of 46*5 million in 1990. This decrease was largely due to decreases in mortality from diarrhoeal disease (from 2*5 to 1*4 million), lower respiratory infections (from 3*4 to 2*8 million), neonatal disorders (from 3*1 to 2*2 million), measles (from 0*63 to 0*13 million), and tetanus (from 0*27 to 0*06 million). Deaths from HIV/AIDS increased from 0*30 million in 1990 to 1*5 million in 2010, reaching a peak of 1*7 million in 2006. Malaria mortality also rose by an estimated 19*9% since 1990 to 1*17 million deaths in 2010. Tuberculosis killed 1*2 million people in 2010. Deaths from non-communicable diseases rose by just under 8 million between 1990 and 2010, accounting for two of every three deaths (34*5 million) worldwide by 2010. 8 million people died from cancer in 2010, 38% more than two decades ago; of these, 1*5 million (19%) were from trachea, bronchus, and lung cancer. Ischaemic heart disease and stroke collectively killed 12*9 million people in 2010, or one in four deaths worldwide, compared with one in five in 1990; 1*3 million deaths were due to diabetes, twice as many as in 1990. The fraction of global deaths due to injuries (5*1 million deaths) was marginally higher in 2010 (9*6%) compared with two decades earlier (8*8%). This was driven by a 46% rise in deaths worldwide due to road traffic accidents (1*3 million in 2010) and a rise in deaths from falls. Ischaemic heart disease, stroke, chronic obstructive pulmonary disease (COPD), lower respiratory infections, lung cancer, and HIV/AIDS were the leading causes of death in 2010. Ischaemic heart disease, lower respiratory infections, stroke, diarrhoeal disease, malaria, and HIV/AIDS were the leading causes of years of life lost due to premature mortality (YLLs) in 2010, similar to what was estimated for 1990, except for HIV/AIDS and preterm birth complications. YLLs from lower respiratory infections and diarrhoea decreased by 45-54% since 1990; ischaemic heart disease and stroke YLLs increased by 17-28%. Regional variations in leading causes of death were substantial. Communicable, maternal, neonatal, and nutritional causes still accounted for 76% of premature mortality in sub-Saharan Africa in 2010. Age standardised death rates from some key disorders rose (HIV/AIDS, Alzheimer's disease, diabetes mellitus, and chronic kidney disease in particular), but for most diseases, death rates fell in the past two decades; including major vascular diseases, COPD, most forms of cancer, liver cirrhosis, and maternal disorders. For other conditions, notably malaria, prostate cancer, and injuries, little change was noted. INTERPRETATION: Population growth, increased average age of the world's population, and largely decreasing age-specific, sex-specific, and cause-specific death rates combine to drive a broad shift from communicable, maternal, neonatal, and nutritional causes towards non-communicable diseases. Nevertheless, communicable, maternal, neonatal, and nutritional causes remain the dominant causes of YLLs in sub-Saharan Africa. Overlaid on this general pattern of the epidemiological transition, marked regional variation exists in many causes, such as interpersonal violence, suicide, liver cancer, diabetes, cirrhosis, Chagas disease, African trypanosomiasis, melanoma, and others. Regional heterogeneity highlights the importance of sound epidemiological assessments of the causes of death on a regular basis. FUNDING: Bill & Melinda Gates Foundation.

Plasma electrochemistry consists of an electrolytic cell where the cathode or the anode is replaced by a direct current (DC) plasma. Unlike conventional electrolysis, highly reactive species such as the solvated electron (e- aq), and the hydroxyl (OH) radical dominate the surface reactions, instead of the properties of the solid electrode. Using this configuration, plasmas have been used to process chemicals, create long-lived chemical species, and synthesize nanoparticles in electrolytic cells. However, which chemical species are introduced to the electrolyte, in what amounts, and how their respective reactions compete, are lingering questions in the field. Here, a non-thermal, atmospheric argon DC plasma was used as a cathode coupled with a platinum anode and aqueous sodium perchlorate (NaClO4) or sodium chloride (NaCl) solutions as background electrolytes. Two chemical compounds, ferricyanide (Fe(CN)6 3-) or methylene blue (MB), were used as chemical indicators to study the competitive reactions driven by e- aq and OH, and various scavengers were used to help identify plausible reaction pathways. A simple kinetic model was used to analyze and interpret the data, revealing that the Faradaic efficiency in these systems is severely limited by the ubiquitous presence of OH.

The estimates of the incidence of deaths and non-fatal injuries from road traffic crashes are essential inputs for prioritising national health and transport policies. This article sketches a methodology for assembling such estimates at the country level by piecing together data from a wide array of sources that include death registers, hospital records, funeral records, health surveys and police reports. Using examples of the types of data sources available in four developing countries (Iran, Mexico, Ghana and India), methods are proposed for making these consistent and extrapolating to estimates of injury incidence at the country level. This requires filling information gaps, mapping from varying case definitions, deriving population-based incidence estimates from sources that may not track denominator populations, and appropriately reapportioning cases assigned to poorly specified causes. The principles proposed here will form the methodological basis for a series of country reports to be published in the future.

Objective: To use a range of existing information sources to develop a national snapshot of the burden of road traffic injuries in one developing country—Iran. Methods: The distribution of deaths was estimated by using data from the national death registration system, hospital admissions and outpatient visits from a timelimited hospital registry in 12 of 30 provinces, and injuries that received no institutional care using the 2000 demographic and health survey. Results were extrapolated to national annual incidence of health burden differentiated by age, sex, external cause, nature of injuries and institutional care. Results: In 2005, 30 721 Iranians died annually in road traffic crashes and over one million were injured. The death rate (44 per 100 000) is the highest of any country in the world for which reliable estimates are available. Road traffic injuries are the third leading cause of death in Iran. While young adults are at high risk in non-fatal crashes, the elderly have the highest total death rates, largely due to pedestrian crashes. While car occupants lead the death count, motorised two-wheeler riders dominate hospital admissions, outpatient visits and health burden. Conclusions: Reliable estimates of the burden of road traffic injuries are an essential input for rational priority setting. Most low income countries are unlikely to have national injury surveillance systems for several decades. Thus national estimates of the burden of injuries should be built by collating information from all existing information sources by appropriately correcting for source specific shortcomings.

With a multi-proxy approach, an attempt was made to constrain productivity and bottom-water redox conditions and their effects on the phosphorus accumulation rate at the Mohammed Plage section on the Tarfaya coast, Morocco, during the Cenomanian-Turonian Anoxic Event (OAE 2). A distinct δ13Corg isotope excursion of +2.5‰ occurs close to the top of the section. The unusually abrupt shift of the isotope excursion and disappearance of several planktonic foraminiferal species (e.g. Rotalipora cushmani and Rotalipora greenhornensis) in this level suggests a hiatus of between 40–60 kyrs at the excursion onset. Nevertheless, it was possible to determine both the long-term environmental history as well as the processes that took place immediately prior to and during OAE 2. TOC% values increase gradually from the base of the section to the top (from ~ 2.5% to ~ 10%). This is interpreted as the consequence of a long-term eustatic sea-level rise and subsidence causing the encroachment of less oxic waters into the Tarfaya Basin. Similarly a reduction in the mineralogically constructed ‘detrital index’ can be explained by the decrease in the continental flux of terrigenous material due to a relative sea-level rise. A speciation of phosphorus in the upper part of the section, which spans the start and mid-stages of OAE 2, shows overall higher abundances of Preactive mass accumulation rates before the isotope excursion onset and lower values during the plateau. Due to the probable short hiatus, the onset of the decrease in phosphorus content relative to the isotope excursion is uncertain, although the excursion plateau already contains lower concentrations. The Corg/Ptotal and V/Al ratios suggest that this reduction was mostly likely caused by a decrease in the available bottom oxygen content (probably as a result of higher productivity) and a corresponding fall in the phosphorus retention ability of the sediment. Productivity appears to have remained high during the isotope plateau possibly due to a combination of ocean-surface fertilisation via increased aridity (increased K/Al and Ti/Al ratios) and/or higher dissolved inorganic phosphorus content in the water column as a result of the decrease in sediment P retention. The evidence for decreased P-burial has been observed in many other palaeoenvironments during OAE 2. Tarfaya's unique upwelling paleosituation provides strong evidence that the nutrient recycling was a global phenomenon and therefore a critical factor in starting and sustaining OAE 2.

This project aims to understand how radiation accelerates corrosion of reactor core materials. The combination of high temperature, chemically aggressive coolants, a high radiation flux and mechanical stress poses a major challenge for the life extension of current light water reactors, as well as the success of most all GenIV concepts. Of these four drivers, the combination of radiation and corrosion places the most severe demands on materials, for which an understanding of the fundamental science is simply absent. Only a few experiments have been conducted to understand how corrosion occurs under irradiation, yet the limited data indicates that the effect is large; irradiation causes order of magnitude increases in corrosion rates. Without a firm understanding of the mechanisms by which radiation and corrosion interact in film formation, growth, breakdown and repair, the extension of the current LWR fleet beyond 60 years and the success of advanced nuclear energy systems are questionable. The proposed work will address the process of irradiation-accelerated corrosion that is important to all current and advanced reactor designs, but remains very poorly understood. An improved understanding of the role of irradiation in the corrosion process will provide the community with the tools to develop predictive modelsmore » for in-reactor corrosion, and to address specific, important forms of corrosion such as irradiation assisted stress corrosion cracking.« less

Geochemical and sedimentological analyses of platinum group element (PGE) patterns across the Cretaceous-Tertiary (KT) transition of eight sections along the Brazos River, Texas, reveal possible sources and processes responsible for PGE enrichments. Of the five global characteristics defining the Cretaceous-Tertiary boundary (KTB) (mass extinction in planktic foraminifera, first appearance of Danian species, negatived 13 C excursion, Ir anomaly, thin (0.5 cm) red clay layer), the Ir anomaly and the red clay layer are not present at the KTB in the Brazos sections. Instead, PGEs and especially Ir show several minor enrichments within the sandstone complex, with the largest peak at the top or just above it. Possible mechanisms of PGE enrichments include low sedimentation rates or sediment starvation that concentrates Ir and other PGEs. Absence of Ir at the KTB is likely linked to dilution effects caused by high sedimentation rates, and other still unknown processes. The source of PGEs remains elusive, but it may be linked to an increased input of extraterrestrial dust during the late Maastrichtian, or reworked PGEs from the Chicxulub impact, which predates the KTB in these sections.

We used data from various sources to triangulate to a national snapshot of the incidence of fatal and non-fatal road traffic injuries in Mexico in 2005. Data sources used include national death registration data, national hospital discharge data and a nationally representative health survey. We estimate that in 2005, 19,389 people died due to injuries and nearly one million were injured in road traffic crashes. While deaths in high-income countries are declining, this is not the case in Mexico. Young adult males are the demographic at the highest risk in non-fatal crashes, but the elderly have the highest road death rates primarily due to pedestrian crashes. Pedestrians alone comprise nearly half (48%) of all deaths. Cars pose a substantial threat to occupants (38% of deaths and 39% of hospital admissions) and to other road users.

We used data from multiple sources to estimate the incidence of fatal and non-fatal road traffic injuries in Sri Lanka in 2005. We validated the accuracy of the data from the national traffic police by comparing with estimates based on national death registration. For estimating the incidence and patterns of non-fatal injuries, we used a nationally represented health survey (World Health Survey), and data on hospital admissions from a rural setting (Galle district). We estimate that in the year 2005, approximately 2300 people died in Sri Lanka due to road traffic crashes, approximately 300,000 were injured in non-fatal crashes and approximately 140,000 received care for their injuries at hospitals. While the road traffic death rate in Sri Lanka is low compared with other low-income countries, it has been steadily rising for several years. Although young adults are at high risk in non-fatal crashes, the elderly have the highest death rate. Pedestrians and bicyclists account for more than half of all road traffic deaths and riders of motorised two-wheelers accounted for an additional 13%. The government of Sri Lanka should act immediately to stop the needless loss of life by implementing the recommendations of the 2004 World Report on Road Traffic Injury Prevention.

Recent studies have made it clear that Iran has too many road traffic injuries (RTI). This paper explains the reasons for high traffic injury rates and points to solutions. It also provides detailed data on the burden of traffic injury in Iran in 2005. Traffic injury rates have rapidly risen out of control because for a variety of possible reasons such as increasing number of non-standard cars and motorcycles, low gas price, decreasing ratio of travels via public transportation than with private vehicles, and problems with safety design. Besides a high need for a system safety approach, Iran needs to deal with the problem of producing a high number of cars and motorcycles. Providing safe mobility for the people of Iran needs to be a top priority of the government.

International audience; BACKGROUND: Measuring disease and injury burden in populations requires a composite metric that captures both premature mortality and the prevalence and severity of ill-health. The 1990 Global Burden of Disease study proposed disability-adjusted life years (DALYs) to measure disease burden. No comprehensive update of disease burden worldwide incorporating a systematic reassessment of disease and injury-specific epidemiology has been done since the 1990 study. We aimed to calculate disease burden worldwide and for 21 regions for 1990, 2005, and 2010 with methods to enable meaningful comparisons over time. METHODS: We calculated DALYs as the sum of years of life lost (YLLs) and years lived with disability (YLDs). DALYs were calculated for 291 causes, 20 age groups, both sexes, and for 187 countries, and aggregated to regional and global estimates of disease burden for three points in time with strictly comparable definitions and methods. YLLs were calculated from age-sex-country-time-specific estimates of mortality by cause, with death by standardised lost life expectancy at each age. YLDs were calculated as prevalence of 1160 disabling sequelae, by age, sex, and cause, and weighted by new disability weights for each health state. Neither YLLs nor YLDs were age-weighted or discounted. Uncertainty around cause-specific DALYs was calculated incorporating uncertainty in levels of all-cause mortality, cause-specific mortality, prevalence, and disability weights. FINDINGS: Global DALYs remained stable from 1990 (2*503 billion) to 2010 (2*490 billion). Crude DALYs per 1000 decreased by 23% (472 per 1000 to 361 per 1000). An important shift has occurred in DALY composition with the contribution of deaths and disability among children (younger than 5 years of age) declining from 41% of global DALYs in 1990 to 25% in 2010. YLLs typically account for about half of disease burden in more developed regions (high-income Asia Pacific, western Europe, high-income North America, and Australasia), rising to over 80% of DALYs in sub-Saharan Africa. In 1990, 47% of DALYs worldwide were from communicable, maternal, neonatal, and nutritional disorders, 43% from non-communicable diseases, and 10% from injuries. By 2010, this had shifted to 35%, 54%, and 11%, respectively. Ischaemic heart disease was the leading cause of DALYs worldwide in 2010 (up from fourth rank in 1990, increasing by 29%), followed by lower respiratory infections (top rank in 1990; 44% decline in DALYs), stroke (fifth in 1990; 19% increase), diarrhoeal diseases (second in 1990; 51% decrease), and HIV/AIDS (33rd in 1990; 351% increase). Major depressive disorder increased from 15th to 11th rank (37% increase) and road injury from 12th to 10th rank (34% increase). Substantial heterogeneity exists in rankings of leading causes of disease burden among regions. INTERPRETATION: Global disease burden has continued to shift away from communicable to non-communicable diseases and from premature death to years lived with disability. In sub-Saharan Africa, however, many communicable, maternal, neonatal, and nutritional disorders remain the dominant causes of disease burden. The rising burden from mental and behavioural disorders, musculoskeletal disorders, and diabetes will impose new challenges on health systems. Regional heterogeneity highlights the importance of understanding local burden of disease and setting goals and targets for the post-2015 agenda taking such patterns into account. Because of improved definitions, methods, and data, these results for 1990 and 2010 supersede all previously published Global Burden of Disease results. FUNDING: Bill & Melinda Gates Foundation.