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Manami Watahiki,1 Shigeo Horinaka,1 Toshihiko Ishimitsu,2 Shigeru Toyoda,1 Teruo Inoue1 1Department of Cardiovascular Medicine, Dokkyo Medical University, Mibu, Japan; 2Department of Kidney and Hypertension, Dokkyo Medical University, Mibu, JapanCorrespondence: Shigeo HorinakaDepartment of Cardiovascular Medicine, Dokkyo Medical University, 880 Kitakobayashi, Mibu, Shimotsuga, Tochigi 321-0293, JapanEmail horinaka@dokkyomed.ac.jpPurpose: The cardio-ankle vascular index, applying the stiffness parameter β theory, was calculated using the pulse-wave velocity and blood pressure from the aortic orifice to the ankle. Accordingly, the impact of the stiffness of the aorta [heart–thigh β (htBETA)] and medium-sized muscular artery [thigh–ankle β (taBETA)] on the stiffness of the heart–ankle β (haBETA) was investigated; further, whether the htBETA (haBETA − taBETA) improved the power of diagnosis of coronary artery disease (CAD) was examined.Materials and Methods: Segmental βs were calculated using VaSela with an additional thigh cuff and compared using the receiver operating characteristic (ROC) curve analysis to evaluate CAD.Results: Overall, 90 healthy subjects and 41 patients with CAD were included. In both groups, haBETA and htBETA, but not taBETA, correlated with age, and taBETA was three times higher than htBETA (p < 0.01). Multiple regression analysis revealed that haBETA can be estimated using htBETA and taBETA in healthy subjects and patients with CAD (r = 0.86, r = 0.67, respectively, p < 0.01), and two-thirds of the haBETA components can be estimated by htBETA using the component analysis. The area under the ROC curve (AUC) for CAD in taBETA (0.493, p = n.s.) was smaller than that in haBETA (0.731, p < 0.01) or htBETA (0.757, p < 0.01); no difference was observed in AUC between haBETA and htBETA.Conclusion: The stiffness of medium-sized muscular arteries of the age-independent thigh–ankle segment (taBETA) was constant, which was three times greater than that of the elastic artery of the heart–thigh artery (htBETA). Two-thirds of the haBETA components could be estimated using htBETA. The ROC curve analysis revealed that the AUC of haBETA could be replaced by that of htBETA, prolonging the measurement segment without affecting the diagnostic power for CAD.Keywords: arterial stiffness, stiffness parameter, cardio-ankle vascular index, coronary artery disease

Objective: To determine the incidence and clinical characteristics of spontaneous haemorrhage into metastatic brain tumours after radiosurgery. Methods: Intratumour haemorrhage rate, clinical features, and treatment were evaluated in 54 patients [...]

Nitrogen isotope analysis of chloropigments provides information on the sources of nitrogenous nutrients assimilated by phytoplankton. The abundant, ubiquitous chlorophyll a records nitrogen isotopic compositions (δ15N) of eukaryotic phytoplankton and cyanobacteria, whereas more source‐specific chloropigments, such as the divinylchlorophylls exclusively possessed by the marine picocyanobacterium Prochlorococcus, can potentially resolve isotopic variability within the phytoplankton community. In this study, we analyzed the δ15N of both chlorophyll a and divinylchlorophyll a isolated from suspended particulate material collected at the subsurface chlorophyll maximum (SCM) along a meridional transect at 88°E in the oligotrophic eastern Indian Ocean. The nitrogen isotopic compositions of Prochlorococcus (δ15NPRO) and the combined biomass of eukaryotic phytoplankton and Synechococcus (δ15NEU+SYN) estimated from the δ15N of divinylchlorophyll a and chlorophyll a, respectively, revealed systematic variations that were not apparent from bulk isotope measurements. Whereas consistently low δ15NPRO indicated reliance of Prochlorococcus on regenerated nitrogen throughout the transect, elevation in δ15NEU+SYN values at several stations was interpreted to reflect assimilation of subsurface NO3− by eukaryotic phytoplankton. The δ15N distributions revealed subtle differences in NO3− availability at the SCM along the transect, which were consistently explained by the occurrence of mesoscale eddies in the Bay of Bengal, deepening of the mixed layer induced by a seasonal Wyrtki Jet in the equatorial region, and substantial deepening of the nutricline in the South Indian Ocean gyre. Our results highlight the utility of compound‐specific isotopic measurements of multiple species of chlorophylls in obtaining essential non‐incubation‐based biogeochemical constraints on the primary production in the ocean. Key Points: We determined nitrogen sources for phytoplankton based on nitrogen isotopic measurements of chlorophyll a and divinylchlorophyll aProchlorococcus depended on regenerated nitrogen whereas eukaryotic phytoplankton responded sensitively to the subsurface nitrate supplyPhytoplankton responses were consistently explained by oceanographic conditions along a meridional transect in the eastern Indian Ocean [ABSTRACT FROM AUTHOR]

δ15N-NH4+ of dairy manure compost piles with and without bulking agent (10% w / w) were compared to understand the significant mitigation of N2O emission by the use of bulking agent. δ15N-NH4+ of each locations of the pile (top, side and core) were also compared. Piles with bulking agent showed significantly higher δ15N values (17.7 ± 1.3‰) than that of the piles without bulking agent (11.8 ± 0.9‰) at the end of the process, reflecting significant higher nitrogen conversion and NH3 loss occurred in the pile with bulking agent. The pile top samples, especially in the piles with bulking agent, showed very high NH4+ concentrations with significant high 15N (δ15N: 12.7-29.8‰) values, indicating extremely high nitrogen conversion, nitrification-denitrification activity of the microbes and NH3 volatilization occurred in this zone. [ABSTRACT FROM AUTHOR]

This paper presents the development of an atmospheric N2O isotopocule model based on a chemistry-coupled atmospheric general circulation model (ACTM). We also describe a simple method to optimize the model and present its use in estimating the isotopic signatures of surface sources at the hemispheric scale. Data obtained from ground-based observations, measurements of firn air, and balloon and aircraft flights were used to optimize the long-term trends, interhemispheric gradients, and photolytic fractionation, respectively, in the model. This optimization successfully reproduced realistic spatial and temporal variations of atmospheric N2O isotopocules throughout the atmosphere from the surface to the stratosphere. The very small gradients associated with vertical profiles through the troposphere and the latitudinal and vertical distributions within each hemisphere were also reasonably simulated. The results of the isotopic characterization of the global total sources were generally consistent with previous one-box model estimates, indicating that the observed atmospheric trend is the dominant factor controlling the source isotopic signature. However, hemispheric estimates were different from those generated by a previous two-box model study, mainly due to the model accounting for the interhemispheric transport and latitudinal and vertical distributions of tropospheric N2O isotopocules. Comparisons of time series of atmospheric N2O isotopocule ratios between our model and observational data from several laboratories revealed the need for a more systematic and elaborate intercalibration of the standard scales used in N2O isotopic measurements in order to capture a more complete and precise picture of the temporal and spatial variations in atmospheric N2O isotopocule ratios. This study highlights the possibility that inverse estimation of surface N2O fluxes, including the isotopic information as additional constraints, could be realized. [ABSTRACT FROM AUTHOR]

The article presents a study on the use of laser spectroscopy for site selective real-time measurements of atmospheric N2O. The study uses technique that is based on mid-infrared quantum cascade laser absorption spectroscopy (QCLAS) combined with an automated preconcentration unit. It also demonstrate the potential of the technique by a three week measurement campaign of atmospheric N2O to identify distinct soil microbial N2O source and sink processes.

We report measurements of the ultraviolet absorption cross sections of OC32S, OC33S, OC34S and O13CS from 195 to 260 nm. The OCS isotopologues were synthesized from isotopically-enriched elemental sulfur by reaction with carbon monoxide. The measured cross section of OC32S is consistent with literature spectra recorded using natural abundance samples. Relative to the spectrum of the most abundant isotopologue, substitution of heavier rare isotopes has two effects. First, as predicted by the reflection principle, the Gaussian-based absorption envelope becomes slightly narrower and blue-shifted. Second, as predicted by Franck-Condon considerations, the weak vibrational structure is red-shifted. Sulfur isotopic fractionation constants (33ε, 34ε) as a function of wavelength are not highly structured, and tend to be close to zero on average on the high energy side and negative on the low energy side. The integrated photolysis rate of each isotopologue at 20 km, the approximate altitude at which most OCS photolysis occurs, was calculated. Sulfur isotopic fractionation constants at 20 km altitude are (-3.7±4.5)‰ and (1.1±4.2)‰ for 33ε and 34ε, respectively, which is inconsistent with the previously estimated large fractionation of over 73‰in 34ε. This demonstrates that OCS photolysis does not produce sulfur isotopic fractionation of more than ca. 5 ‰, suggesting OCS may indeed be a significant source of background stratospheric sulfate aerosols. Finally, the predicted isotopic fractionation constant for 33S excess (33E) in OCS photolysis is (-4.2±6.6) ‰, and thus photolysis of OCS is not expected to be the source of the non-mass-dependent signature observed in modern and Archaean samples. [ABSTRACT FROM AUTHOR]

The article presents a study which develops and optimizes a liquid nitrogen-free preconcentration unit to measure the ambient nitrous oxide (N2O) isoptomers using quantum cascade laser absorption spectroscopy (QCLAS). It states that 101 of ambient air are desorbed in 50 ml of synthetic air and preconcentrated on a HayeSep D trap during the standard operation. The results show that a quantitative N2O recovery of greater than 99% has been achieved.

It is suggested that the uplift of Himalaya-Tibetan Plateau enhanced interior aridity in East Asia and resulted in development of middle latitude gobi and sandy deserts and accumulation of the eolian sediments in the Chinese Loess Plateau. Therefore, estimation of the provenance for eolian sediments in the Chinese Loess Plateau is critical to reconstruct the environmental changes in East Asia and their relation to the Himalaya-Tibetan Plateau uplift. We recently developed a new provenance tracing method by using a combination of Electron Spin Resonance (ESR) signal intensity and Crystallinity Index (CI) of quartz, and demonstrated that fine fraction of the surface sediments from nine major deserts in East Asia could be distinguished one another on the ESR signal intensity versus CI diagram. Here, we measured ESR signal intensity and CI of quartz in fine fractions of samples covering the last 7Ma obtained from Lingtai section in the central Chinese Loess Plateau, and compared the results with those of the surface samples from nine major deserts in East Asia. The results suggest that the provenance of fine fraction of the eolian sediment in Lingtai section changed at 4.3, 2.1, 1.4, 1.1, 0.8 and 0.4 Ma. During 7 to 4.3 Ma, the dust might be have been supplied from Precambrian to Paleozoic metamorphic and granitic rocks and granite exposed in the present central to eastern part of the Tian Shan Mountains. The contribution from the Taklimakan desert appeared at 4.3 Ma, increased drastically at 1.1 Ma, and persisted till 0.8 Ma, whereas the main source of detrital material to the Taklimakan desert might have changed from eastern part of the Kunlun and the Altyn Mountains to western part of the Kunlun and the Tian Shan Mountains. During 0.8 to 0.4 Ma, contribution from the Badain Juran desert gradually increased. Finally, contribution from the Tengger desert appeared from 0.4 to 0 Ma. Together with tectonic evidences from literatures, the provenance changes from 4.3 to 0.8Ma seem to reflect uplift of the Tian Shan and the Kunlun Mountains and consequent formation of the Taklimakan desert, whereas the change at 0.4Ma may reflect uplift of the Qilian Mountains although formation of mountain glaciers could be an alternative possibility. These provenance changes will provide important constraints not only on the development of arid areas and evolution of monsoon but also on the uplift and erosion of mountains in East Asia. [ABSTRACT FROM AUTHOR]