Disentangling source of moisture driving glacier dynamics and identification of 8.2 ka event: evidence from pore water isotopes, Western Himalaya

Two atmospheric circulation patterns, the Indian Summer Monsoon (ISM) and mid-latitude Westerlies control precipitation and thus glacier variability in the Himalaya. However, the role of the ISM and westerlies in controlling climate and thus past glacier variability in the Himalaya is poorly understood because of the paucity of the ice core records. In this article, we present a new Holocene paleorecord disentangling the presence of the ISM and mid-latitude westerlies and their effect on glacier fluctuations during the Holocene. Our new record is based on high-resolution multi-proxy analyses (δ18Oporewater, deuterium-excess, grain size analysis, permeability, and environmental magnetism) of lake sediments retrieved from Chandratal Lake, Western Himalaya. Our study provides new evidence that improves the current understanding of the forcing factor behind glacier advances and retreat in the Western Himalaya and identifies the 8.2 ka cold event using the aforementioned proxies. The results indicate that the ISM dominated precipitation ~ 21% of the time, whereas the mid-latitude westerlies dominated precipitation ~ 79% of the time during the last 11 ka cal BP. This is the first study that portrays the moisture sources by using the above proxies from the Himalayan region as an alternative of ice core records.publishedVersio

Corrigendum: Image-based siRNA screen to identify kinases regulating Weibel-Palade body size control using electroporation.

This corrects the article DOI: 10.1038/sdata.2017.22

Characterisation and effects of a xylanase enzyme preparation extracted from Thermomyces lanuginosus cultures

This paper describes the production of an enzyme preparation from the fungus Thermomyces lanuginosus. Thermal resistance, pH stability and lignocellulolytic activity of the enzyme preparation high in xylanase were studied on a variety of grains and forages. The enzyme preparation preserved more than 70% of its original xylanase activity for 4 and 1 h at 60 and 70 °C, respectively. The xylanase activity remained over 80% when the preparation was incubated for 30 min at pH 4.5. In vitro digestibility studies indicated that the enzyme digested 7.5, 8.5 and 8.0% of the dry matter (DM) of barley meal, wheat bran and oat meal samples, respectively. When applying 60-min incubation, 7.5, 7.3 and 8.4% of DM of the oat straw, alfalfa hay and triticale straw was digested, respectively. When the time of digestion was increased to 360 min, the sunflower hull showed 15.8% DM digestibility

Bosniak category III cysts are more likely to be malignant than we expected in the era of multidetector computed tomography technology

Background: Complex indeterminate Bosniak category III renal cystic masses are traditionally considered to be malignant in 50%. Our aim was to retrospectively evaluate the attenuation characteristics in multiphase computed tomography (CT) and to determinate the incidence of malignancy based on histological findings on all Bosniak category III renal cystic masses investigated in our department between April 3, 2007 and November 21, 2013. Materials and Methods: Quadriphasic multidetector CT images of nineteen patients (mean age: 56.5 +/- 16.5 years) with radiologically detected Bosniak category III lesions were reviewed retrospectively. All lesions were surgically removed, and the incidence of malignancy, based on pathological results was determined. Results: Calcification was present in four lesions (21%). The mean largest diameter was 48.7 +/- 28.8 mm. All lesions were multilobulated and septated. Of the 19 removed lesions, 16 (84%) were malignant, and 3 (16%) were benign (one inflammatory cyst including a nephrolith, one cystic nephroma and one atypical angiomyolipoma). CT and histological findings of 19 Bosniak III cysts were correlated. Conclusion: Our study demonstrated much higher prevalence of malignancy (84%) in radiologically detected Bosniak category III cysts than it has been described before. It may due to the era of modern multidetector CT technology and multiphase protocol

Assessment of choroidal blood flow using laser speckle flowgraphy

Background/aims There is considerable interest in novel techniques to quantify choroidal blood flow (CBF) in humans. In the present study, we investigated a novel technique to measure CBF based on laser speckle flowgraphy (LSFG) in healthy subjects. Methods This study included 31 eyes of 31 healthy, non-smoking subjects aged between 19 and 74 years. A commercial LSFG instrument was used to measure choroidal vessel diameter (CVD) and relative flow volume (RFV) in choroidal vessels that were identified on fundus photos, an approach that was used previously only for retinal vessels. The reproducibility and the effect of isometric exercise on these parameters were investigated. The latter was compared with measurement of subfoveal CBF using laser Doppler flowmetry (LDF). Results Intraclass correlation coefficients for CVD and RFV were higher than 0.8 indicating excellent reproducibility. During isometric exercise, we observed an increase in ocular perfusion pressure of approximately 60% (P<0.001). The increase in RFV and CBF was lower, but also highly significant versus baseline (at minute 6 of isometric exercise: RFV 10.5%+/- 4.2%, CBF 8.3%+/- 3.6%;P< 0.001 each) indicating choroidal autoregulation. Conclusion LSFG may be a novel approach to study blood flow in choroidal vessels. Data are reproducible and show good agreement with LDF data

Reverse Hall-Petch effect in ultra nanocrystalline diamond

We present atomistic simulations for the mechanical response of ultra nanocrystalline diamond, a polycrystalline form of diamond with grain diameters of the order of a few nm. We consider fully three-dimensional model structures, having several grains of random sizes and orientations, and employ state-of-the-art Monte Carlo simulations. We calculate structural properties, elastic constants and the hardness of the material; our results compare well with experimental observations for this material. Moreover, we verify that this material becomes softer at small grain sizes, in analogy to the observed reversal of the Hall-Petch effect in various nanocrystalline metals. The effect is attributed to the large concentration of grain boundary atoms at smaller grain sizes. Our analysis yields scaling relations for the elastic constants as a function of the average grain size.Comment: Proceedings of the IUTAM Symposium on Modelling Nanomaterials and Nanosystems, Aalborg, Denmark, May 19-22 2008; to be published in the IUTAM Bookseries by Springe

Evaluation of flicker induced hyperemia in the retina and optic nerve head measured by Laser Speckle Flowgraphy

Purpose The coupling between neural activity and blood flow is a physiological key principle of ocular blood flow regulation. The current study was performed to investigate whether Laser speckle flowgraphy (LSFG), a commercially available technique for measuring blood flow, is capable to assess flicker-induced haemodynamic changes in the retinal and optic nerve head (ONH) circulation. Methods Twenty healthy subjects were included in this cross sectional study. A commercial LSFG instrument was used to measure blood flow at the ONH as well as in retinal vessels before and during stimulation with flickering light. Mean blur rate (MBR), a measure of relative blood flow velocity, was obtained for the ONH and relative flow volume (RFV) a measure of relative blood flow of the respective retinal vessels. Results Stimulation with flicker light increased ONH MBR by +17.5%+/- 6.6% (p<0.01). In retinal arteries, flicker stimulation led an increase of +23.8 +/- 10.0% (p<0.05) in total RFV. For retinal veins, an increase of +23.1%+/- 11.0 (p<0.05) in total RFV was observed during stimulation. A higher response was observed in nasal RFV compared to temporal RFV in retinal arteries (nasal: +28.9%+/- 20.0%;temporal: +20.4%+/- 17.6%, p<0.05) and veins (nasal: +28.3%+/- 19.6%;temporal +17.8%+/- 18.9%, p<0.05). Conclusion As shown previously with other techniques, flicker stimulation leads to an increase in retinal and optic nerve head blood flow. Our results indicate that LSFG is an appropriate method for the quantification of retinal and ONH blood flow during visual stimulation and may be used as a non-invasive, easy to use tool to assess neuro-vascular coupling in humans

Ocular Blood Flow Measurements in Healthy White Subjects Using Laser Speckle Flowgraphy

Purpose. To assess the feasibility and reliability of Laser Speckle Flowgraphy (LSFG) to measure ocular perfusion in a sample of healthy white subjects and to elucidate the age-dependence of the parameters obtained. Methods: This cross-sectional study included 80 eyes of 80 healthy, non-smoking white subjects of Western European descent between 19 and 79 years of age. A commercial LSFG instrument was applied to measure ocular blood flow at the optic nerve head (ONH) three successive times before and after pharmacological pupil dilation. The mean blur rate (MBR), a measure of relative blood flow velocity, was obtained for different regions of the ONH. Eight parameters of ocular perfusion derived from the pulse-waveform analysis of MBR including blowout time (BOT) and falling rate (FR) were also recorded. Results Artifact-free LSFG images meeting the quality criteria for automated image analysis were obtainable in 93.8% without pupil dilation and in 98.8% with pharmacological pupil dilation. Measurements of MBR showed excellent repeatability with intraclass correlation coefficients >= 0.937 and were barely affected by pupil dilation. The majority of pulse-waveform derived variables exhibited equally high repeatability. MBR-related blood flow indices exhibited significant age dependence (p<0.001). FR (r = 0.747, p<0.001) and BOT (r = -0.714, p<0.001) most strongly correlated with age. Conclusions: LSFG represents a reliable method for the quantitative assessment of ocular blood flow in white subjects. Our data affirms that the LSFG-derived variables FR and BOT may be useful biomarkers for age-related changes in ocular perfusion