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Samples of the carbonaceous asteroid (162173) Ryugu were collected and brought to Earth by the Hayabusa2 spacecraft. We investigated the macromolecular organic matter in Ryugu samples and found that it contains aromatic and aliphatic carbon, ketone, and carboxyl functional groups. The spectroscopic features of the organic matter are consistent with those in chemically primitive carbonaceous chondrite meteorites that experienced parent-body aqueous alteration (reactions with liquid water). The morphology of the organic carbon includes nanoglobules and diffuse carbon associated with phyllosilicate and carbonate minerals. Deuterium and/or nitrogen-15 enrichments indicate that the organic matter formed in a cold molecular cloud or the presolar nebula. The diversity of the organic matter indicates variable levels of aqueous alteration on Ryugu's parent body.

We report on the design and performance of a double-sided coincidence velocity map imaging spectrometer optimized for electron-ion and ion-ion coincidence experiments studying inner-shell photoionization of gas-phase molecules with soft X-ray synchrotron radiation. The apparatus employs two microchannel plate detectors equipped with delay-line anodes for coincident, time- and position-resolved detection of photoelectrons and Auger electrons with kinetic energies up to 300 eV on one side of the spectrometer and photoions up to 25 eV per unit charge on the opposite side. We demonstrate its capabilities by measuring valence photoelectrons and ion spectra of neon and nitrogen and by studying channel-resolved photoelectron and Auger spectra along with fragment-ion momentum correlations for chlorine 2p inner-shell ionization of cis- and trans-1,2-dichloroethene.

The sources and nature of organic carbon on Mars have been a subject of intense research. Steele et al. (2012) showed that 10 martian meteorites contain macromolecular carbon phases contained within pyroxene- and olivine-hosted melt inclusions. Here, we show that martian meteorites Tissint, Nakhla, and NWA 1950 have an inventory of organic carbon species associated with fluid-mineral reactions that are remarkably consistent with those detected by the Mars Science Laboratory (MSL) mission. We advance the hypothesis that interactions among spinel-group minerals, sulfides, and a brine enable the electrochemical reduction of aqueous CO 2 to organic molecules. Although documented here in martian samples, a similar process likely occurs wherever igneous rocks containing spinel-group minerals and/or sulfides encounter brines.

Lithium-rich layered transition metal oxide positive electrodes offer access to anion redox at high potentials, thereby promising high energy densities for lithium-ion batteries. However, anion redox is also associated with several unfavorable electrochemical properties, such as open-circuit voltage hysteresis. Here we reveal that in Li 1.17-x Ni 0.21 Co 0.08 Mn 0.54 O 2 , these properties arise from a strong coupling between anion redox and cation migration. We combine various X-ray spectroscopic, microscopic, and structural probes to show that partially reversible transition metal migration decreases the potential of the bulk oxygen redox couple by > 1 V, leading to a reordering in the anionic and cationic redox potentials during cycling. First principles calculations show that this is due to the drastic change in the local oxygen coordination environments associated with the transition metal migration. We propose that this mechanism is involved in stabilizing the oxygen redox couple, which we observe spectroscopically to persist for 500 charge/discharge cycles.

The fragmentation dynamics of 2,6- and 3,5-difluoroiodobenzene after iodine 4d inner-shell photoionization with soft X-rays are studied using coincident electron and ion momentum imaging. By analyzing the momentum correlation between iodine and fluorine cations in three-fold ion coincidence events, we can distinguish the two isomers experimentally. Classical Coulomb explosion simulations are in overall agreement with the experimentally determined fragment ion kinetic energies and momentum correlations and point toward different fragmentation mechanisms and time scales. While most three-body fragmentation channels show clear evidence for sequential fragmentation on a time scale larger than the rotational period of the fragments, the breakup into iodine and fluorine cations and a third charged co-fragment appears to occur within several hundred femtoseconds.

Fluid phase transitions inside single, isolated carbon nanotubes are predicted to deviate substantially from classical thermodynamics. This behaviour enables the study of ice nanotubes and the exploration of their potential applications. Here we report measurements of the phase boundaries of water confined within six isolated carbon nanotubes of different diameters (1.05, 1.06, 1.15, 1.24, 1.44 and 1.52 nm) using Raman spectroscopy. The results reveal an exquisite sensitivity to diameter and substantially larger temperature elevations of the freezing transition (by as much as 100 °C) than have been theoretically predicted. Dynamic water filling and reversible freezing transitions were marked by 2-5 cm -1 shifts in the radial breathing mode frequency, revealing reversible melting bracketed to 105-151 °C and 87-117 °C for 1.05 and 1.06 nm single-walled carbon nanotubes, respectively. Near-ambient phase changes were observed for 1.44 and 1.52 nm nanotubes, bracketed between 15-49 °C and 3-30 °C, respectively, whereas the depression of the freezing point was observed for the 1.15 nm nanotube between -35 and 10 °C. We also find that the interior aqueous phase reversibly decreases the axial thermal conductivity of the nanotube by as much as 500%, allowing digital control of the heat flux.

This study assesses the quantitative effects of incorporating high-volume fly ash (HVFA) into tricalcium silicate (C₃S) paste on the hydration, degree of silicate polymerization, and Al substitution for Si in calcium silicate hydrate (C-S-H). Thermogravimetric analysis and isothermal conduction calorimetry showed that, although the induction period of C₃S hydration was significantly extended, the degree of hydration of C₃S after the deceleration period increased due to HVFA incorporation. Synchrotron-sourced soft X-ray spectromicroscopy further showed that most of the C₃S in the C₃S-HVFA paste was fully hydrated after 28 days of hydration, while that in the pure C₃S paste was not. The chemical shifts of the Si K edge peaks in the near-edge X-ray fine structure of C-S-H in the C₃S-HVFA paste directly indicate that Al substitutes for Si in C-S-H and that the additional silicate provided by the HVFA induces an enhanced degree of silicate polymerization. This new spectromicroscopic approach, supplemented with 27 Al and 29 Si magic-angle spinning nuclear magnetic resonance spectroscopy and transmission electron microscopy, turned out to be a powerful characterization tool for studying a local atomic binding structure of C-S-H in C₃S-HVFA system and presented results consistent with previous literature.

An experimental route to identify and separate geometric isomers by means of coincident Coulomb explosion imaging is presented, allowing isomer-resolved photoionization studies on isomerically mixed samples. We demonstrate the technique on cis/trans 1,2-dibromoethene (C 2 H 2 Br 2 ). The momentum correlation between the bromine ions in a three-body fragmentation process induced by bromine 3d inner-shell photoionization is used to identify the cis and trans structures of the isomers. The experimentally determined momentum correlations and the isomer-resolved fragment-ion kinetic energies are matched closely by a classical Coulomb explosion model.

The understanding and control of early hydration of tricalcium silicate (C₃S) is of great importance to cement science and concrete technology. However, traditional characterization methods are incapable of providing morphological and spectroscopic information about in situ hydration at the nanoscale. Using soft X-ray spectromicroscopy, we report the changes in morphology and molecular structure of C₃S at an early stage of hydration. In situ C₃S hydration in a wet cell, beginning with induction (~1 h) and acceleration (~4 h) periods of up to ~8 h, was studied and compared with ex situ measurements in the deceleration period after 15 h of curing. Analysis of the near-edge X-ray absorption fine structure showed that the Ca binding energy and energy splitting of C₃S changed rapidly in the early age of hydration and exhibited values similar to calcium silicate hydrate (C-S-H). The formation of C-S-H nanoseeds in the C₃S solution and the development of a fibrillar C-S-H morphology on the C₃S surface were visualized. Following this, silicate polymerization accompanied by C-S-H precipitation produced chemical shifts in the peaks of the main Si K edge and in multiple scattering. However, the silicate polymerization process did not significantly affect the Ca binding energy of C-S-H.

Stromatolites composed of apatite occur in post-Lomagundi-Jatuli successions (late Palaeoproterozoic) and suggest the emergence of novel types of biomineralization at that time. The microscopic and nanoscopic petrology of organic matter in stromatolitic phosphorites might provide insights into the suite of diagenetic processes that formed these types of stromatolites. Correlated geochemical micro-analyses of the organic matter could also yield molecular, elemental and isotopic compositions and thus insights into the role of specific micro-organisms among these communities. Here, we report on the occurrence of nanoscopic disseminated organic matter in the Palaeoproterozoic stromatolitic phosphorite from the Aravalli Supergroup of north-west India. Organic petrography by micro-Raman and Transmission Electron Microscopy demonstrates syngeneity of the organic matter. Total organic carbon contents of these stromatolitic phosphorite columns are between 0.05 and 3.0 wt% and have a large range of δ(13) Corg values with an average of -18.5‰ (1σ = 4.5‰). δ(15) N values of decarbonated rock powders are between -1.2 and +2.7‰. These isotopic compositions point to the important role of biological N2 -fixation and CO2 -fixation by the pentose phosphate pathway consistent with a population of cyanobacteria. Microscopic spheroidal grains of apatite (MSGA) occur in association with calcite microspar in microbial mats from stromatolite columns and with chert in the core of diagenetic apatite rosettes. Organic matter extracted from the stromatolitic phosphorites contains a range of molecular functional group (e.g. carboxylic acid, alcohol, and aliphatic hydrocarbons) as well as nitrile and nitro groups as determined from C- and N-XANES spectra. The presence of organic nitrogen was independently confirmed by a CN(-) peak detected by ToF-SIMS. Nanoscale petrography and geochemistry allow for a refinement of the formation model for the accretion and phototrophic growth of stromatolites. The original microbial biomass is inferred to have been dominated by cyanobacteria, which might be an important contributor of organic matter in shallow-marine phosphorites., (© 2015 John Wiley & Sons Ltd.)

We report on the successful installation and operation of a scanning transmission x-ray microspectroscope (STXM) at the PolLux facility at the Swiss Light Source. This integration of an advanced STXM with improved sample handling capabilities and a novel beamline provides unique capabilities. PolLux uses linearly or circularly polarized x-rays from a bending magnet with an extended photon energy range (200-1400 eV). It is therefore well suited to determine a sample's quantitative chemical composition, molecular orientation, or thickness of organic as well as condensed matter materials. The local magnetic state of magnetic thin films is accessible through fast helicity switching by steering the electron beam off axis through the bending magnet. Ex vacuo girder movers allow fast and highly reproducible (<1 microm) alignment of the instrument with respect to the photon beam. The present spatial resolution is approximately 20 nm, limited by the zone plates utilized. The instrument has the stability and positional resolution to operate with much higher resolution optics as it becomes available. In addition to characterization experiments, we present several typical examples from materials research and environmental science to exemplify the capabilities.

The high brightness of the bend magnets at the Advanced Light Source has been exploited to illuminate a scanning transmission X-ray microscope (STXM). This is the first diffraction-limited scanning X-ray microscope to operate with a useful count rate on a synchrotron bend-magnet source. A simple dedicated beamline has been built covering the range of photon energy from 250 eV to 600 eV. The beamline is always available and needs little adjustment. Use of this facility is much easier than that of installations that share undulator beams. This facility provides radiation for C 1s, N 1s and O 1s near-edge X-ray absorption spectromicroscopy with STXM count rates in excess of 1 MHz and with spectral resolution typically 1:2000, limited to about 1:5000.

The Kilkenny Health Project was a community research and demonstration programme which aimed to reduce risk of cardiovascular disease in a county in the south-east of Ireland with a total population of approximately 70,000. The health promotion programme was carried out in Kilkenny from 1985 to 1992. Outcome evaluation was by means of population surveys of independent samples of men and women aged 35 to 64 years in Kilkenny (n approximately 800) and in the reference county (n approximately 600) in 1985/1986 and in 1990/1991. Survey methods for health behaviour questionnaires and risk factor measurements were similar to those of the WHO MONICA Project. Mean systolic blood pressure (SBP) declined significantly (P < 0.01) in men and women in both counties, from 144.0 by 5.4 mmHg and from 143.2 by 5.4 mmHg in men and from 139.5 by 7.7 mmHg and from 136.5 by 6.6 mmHg in women in the intervention and reference counties. The prevalence of hypertension declined from 23.1% by 2.8% and from 26.1% by 6.0% in men in the two counties. Prevalence declined from 24.1% by 6.2% (P < 0.05) in women in the intervention county but was unchanged, increasing by 0.5% from 17.5%, in women in the reference county. Mean serum total cholesterol declined from 6.04 mmol.l-1 by 0.09 mmol.l-1 and from 6.00 by 0.44 mmol.l-1 (P < 0.01) in men and from 6.01 by 0.36 (P < 0.01) and from 5.90 by 0.31 (P < 0.01) in women in the intervention and reference counties, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Objective: To assess the use of acute coronary care facilities in the Republic of Ireland with regard to case mix, patient characteristics, mortality and factors associated with mortality, time intervals to admission, utilisation of thrombolysis, and risk factor profiles., Design: A 1 week prospective census of all hospitals admitting acute coronary cases. These comprised 23 coronary care units (CCU) and 17 combined coronary care/intensive care units (CCU/ICU). Data were collected by standardised methods on each new patient "upon whom a cardiac monitor was placed"., Results: Acute coronary heart disease was confirmed in 185 (44.9%) of 412 patients. Of these 109 (26.4%) had a confirmed myocardial infarction and 76 (18.4%) unstable angina. Women were significantly older than men in all groups. Of those with proven acute coronary heart disease, 42.6% were current smokers, 23.1% were aware of having a raised cholesterol concentration, and 42.3% gave a history of prior hypertension. Only 44% were transported by ambulance. Median delay time from the onset of symptoms to admission was 6 h in Dublin and 4 h elsewhere. 34.9% of patients with a confirmed myocardial infarction received thrombolysis. Mortality of patients with myocardial infarction CCU/ICU at 7 days was 10.9 %., Conclusions: There is potential for considerable improvement in the management of coronary heart disease in the Republic of Ireland through a reduction in delay times to admission to hospital, increased use of thrombolytic treatment, and intensification of advice on primary and secondary risk factors.

As part of the evaluation of the Kilkenny Health Project, a survey of factors associated with increased risk of coronary heart disease (CHD) was carried out in Kilkenny, Ireland, in 1985. A random sample of 784 men and women aged 35 to 64 years was surveyed. Mean serum total cholesterol was mmol/l in men and women; 7.0% had levels greater than 7.8 mmol/l. Serum total cholesterol was significantly associated with age. 23.4% of males and 23.6% of females were hypertensive. 60.9% of males and 56.4% of females who were hypertensive were not on treatment. The prevalence of regular cigarette smoking was similar in males (27.7%) and females (27.1%). A further 6.3% of males and 1.6% of females smoked cigarettes occasionally or smoked a pipe or cigars regularly. 4.5% had a positive Rose questionnaire for previous myocardial infarction and 3.4% had a positive angina questionnaire. The high median total cholesterol and the low proportion of hypertensives on medication are consistent with findings in other population surveys in the British Isles and with the high mortality rates from CHD in Ireland. The prevalence of hypercholesterolaemia and of untreated hypertension was higher than in population surveys in the United States and Australia where CHD mortality rates are lower and declining at a faster rate than in Ireland.

Ireland has one of the highest death rates in the world from coronary heart disease (CHD) and has not shared in the rapid decline in mortality which has occurred in other countries. The Kilkenny Health Project was established as a community-based research and demonstration programme for cardiovascular disease prevention in County Kilkenny and as a pilot project for future national initiatives. The first phase of the health promotion programme in Kilkenny is being carried out between 1985 and 1990. Changes in behaviour and in factors associated with CHD will be estimated by the difference in changes over time between Kilkenny and the reference area, as measured by independent random sample surveys of men and women aged 35 to 64 years. CHD and stroke events, fatal and non-fatal, will be registered in both areas from 1987-1992. The Project has studied attitudes to CHD and its prevention. Health behaviours have been studied in adults and in post-primary school pupils. Risk factors for CHD have been measured in adults in accordance with the methods of the international MONICA Project. It has been demonstrated that health and education professionals can incorporate preventive activities and health education into everyday practice.

We examined the prevalence of different categories of body weight in a random sample of men and women aged 35 to 64 years studied in 1985 in County Kilkenny, Ireland. The largest group was those classified as overweight-51.1% of men and 44.7% of women. There were 13.7% of men and 19.2% of women in the obese category. The obese were older but the distribution by social class did not differ significantly from the non-obese. Obese women had significantly more children born alive and a higher prevalence of positive angina questionnaire than those who were not obese. Serum total cholesterol was higher in obese men and HDL cholesterol was lower in obese men and obese women. Systolic and diastolic blood pressures were significantly higher in obese men and women but smoking status was similar. In a multiple logistic regression analysis, systolic blood pressure in men and diastolic in women remained significantly associated with obesity; there was an inverse association between obesity and HDL cholesterol in women and between obesity and HDL-cholesterol as a proportion of total cholesterol in men. A cardiovascular disease prevention programme should seek to prevent the increase in the prevalence of obesity with age which occurs in this population. It would also be important to assess other risk factors for coronary heart disease among those who are obese, with a view to reducing their overall level of risk.