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The isotopic composition of Si in biogenic silica (BSi), such as opal buried in the oceans' sediments, has changed over time. Paleorecords suggest that the isotopic composition, described in terms of δ30Si, was generally much lower during glacial times than today. There is consensus that this variability is attributable to differing environmental conditions at the respective time of BSi production and sedimentation. The detailed links between environmental conditions and the isotopic composition of BSi in the sediments remain, however, poorly constrained. In this study, we explore the effects of a suite of offset boundary conditions during the Last Glacial Maximum (LGM) on the isotopic composition of BSi archived in sediments in an Earth System Model of intermediate complexity (EMIC). Our model results suggest that a change in the isotopic composition of Si supply to the glacial ocean is sufficient to explain the observed overall low(er) glacial δ30Si in BSi. All other processes explored trigger model responses of either wrong sign or magnitude or are inconsistent with a recent estimate of bottom water oxygenation in the Atlantic Sector of the Southern Ocean. Caveats, mainly associated with generic uncertainties in today's pelagic biogeochemical modules, remain. Key Points: We simulate the isotopic composition of biogenic silica archived in the ocean's sedimentOur simulations with an Earth System Model compare modern climate to glacial conditionsOut of several hypotheses tested, altering the isotopic composition of runoff during the LGM is most consistent with proxies [ABSTRACT FROM AUTHOR]

Cu(In,Ga)Se2 (CIGS) solar cells in superstrate configuration promise improved light management and higher stability compared to substrate devices, but they have yet to deliver comparable power conversion efficiencies (PCEs). Chemical reactions between the CIGS layer and the front contact were shown in the past to deteriorate the p-n junction in superstrate devices, which led to lower efficiencies compared to the substrate-type devices. This work aims to solve this problem by identifying a buffer layer between the CIGS layer and the front contact, acting as the electron transport layer, with an optimized electron affinity, doping density and chemical stability. Using combinatorial material exploration we identified amorphous gallium oxide (a-GaO x) as a potentially suitable buffer layer material. The best results were obtained for a-GaO x with an electron affinity that was found to be comparable to that of CIGS. Based on the results of device simulations, it is assumed that detrimental interfacial acceptor states are present at the interface between CIGS and a-GaO x. However, these initial experiments indicate the potential of a-GaO x in this application, and how to reach performance parity with substrate devices, by further increase of its n-type doping density. [ABSTRACT FROM AUTHOR]

Copper-oxide compound semiconductors provide a unique possibility to tune the optical and electronic properties from insulating to metallic conduction, from bandgap energies of 2.1 eV to the infrared at 1.40 eV, i.e., right into the middle of the efficiency maximum for solar-cell applications. Three distinctly different phases, Cu2O, Cu4O3, and CuO, of this binary semiconductor can be prepared by thin-film deposition techniques, which differ in the oxidation state of copper. Their material properties as far as they are known by experiment or predicted by theory are reviewed. They are supplemented by new experimental results from thin-film growth and characterization, both will be critically discussed and summarized. With respect to devices the focus is on solar-cell performances based on Cu2O. It is demonstrated by photoelectron spectroscopy (XPS) that the heterojunction system p-Cu2O/n-AlGaN is much more promising for the application as efficient solar cells than that of p-Cu2O/n-ZnO heterojunction devices that have been favored up to now. [ABSTRACT FROM AUTHOR]

This study evaluated the accuracy and reliability of the Dinamap 8100 automated blood pressure machine against three internationally recognized criteria. Systolic and diastolic blood pressures were taken concurrently by two nurses using the automated machine and a manual sphygmomanometer. Results demonstrated agreement between automated and manual readings on one set of criteria for both systolic and diastolic pressures, and support for systolic readings only on one other criterion. Comparison of mean differences between automated and manual measures showed the automated machine consistently under-read both systolic and diastolic blood pressures. The conclusion from this study was that the Dinamap 8100 machine can be used with some degree of confidence to assess systolic blood pressures in a general population of adult hospital inpatients, but with caution when taking diastolic readings. [ABSTRACT FROM AUTHOR]

Unlabelled: We measured Protein S-100 serum levels in 66 healthy newborns during the first week of life and in 7 newborns with perinatal acidosis. Normal values (n = 66) constantly ranged between 0.66 and 3.33 microg/l (2.5 and 97.5 percentiles) during the evaluation period.Conclusions: Newborns with signs of hypoxic-ischaemic encephalopathy (HIE) after perinatal acidosis showed elevated Protein S-100 serum levels, whereas newborns without these signs had normal concentrations. S-100 might thus be a marker of central nervous system damage in newborns. Key words: Asphyxia, brain damage, neonate [ABSTRACT FROM AUTHOR]

An infant with combined methylmalonic aciduria and homocystinuria (cblC/D defect) presented with significant VSD. She underwent successful cardiac surgery at 53 days. [ABSTRACT FROM AUTHOR]

Background: Primary sclerosing cholangitis (PSC) is a progressive bile duct disease associated with inflammatory bowel disease (PSC-IBD)., Aim: To investigate whether patients with PSC-IBD benefit from a gluten-free and amylase trypsin inhibitor (ATI)-free diet (GFD)., Methods: We performed a prospective clinical pilot study administering an eight-week GFD. The primary outcomes were colonic inflammation assessed by proctosigmoidoscopy, and liver stiffness (surrogate for fibrosis, inflammation and cholestasis) measured by transient elastography before and after GFD. Amongst the secondary (exploratory) outcomes were colonic mucosal and serum cytokine/chemokine changes, the intestinal microbiome and transcriptome dynamics, and shifts in serum markers of hepatic fibrogenesis., Results: Fifteen patients with PSC-IBD completed the study. The study did not meet its primary outcome: the endoscopic score and liver stiffness remained unchanged. However, the expression of pro-inflammatory mucosal cytokines and chemokines such as IL6, IL8, CCL2, and TNFα was significantly down-regulated. Two critical markers of liver fibrosis and matrix remodelling, thrombospondin-2 and -4, decreased significantly. The microbiota composition changed slightly, including a decrease in the pathogen Romboutsia ilealis. The intestinal transcriptome indicated a gut barrier improvement. Pruritus, fatigue, overall well-being, faecal calprotectin levels, and serum alkaline phosphatase did not change significantly., Conclusions: This study did not demonstrate a clinical improvement with short-term GFD in patients with PSC-IBD. However, a gluten/ATI-free diet may improve biomarkers of intestinal inflammation and barrier function in these patients with associated changes in the enteric microbiota. Further investigation of the therapeutic potential of the GFD in PSC-IBD is warranted., (© 2022 The Authors. Alimentary Pharmacology & Therapeutics published by John Wiley & Sons Ltd.)

Background & Aims: Biliary strictures are common complications after orthotopic liver transplantation. Endoscopic retrograde cholangiography evolved as standard and percutaneous transhepatic cholangiodrainage as alternative therapy. This study analysed predictors of long-term success of biliary strictures after endoscopic retrograde cholangiography and/or percutaneous transhepatic cholangiodrainage and its impact on patient survival., Methods: All adult patients with biliary strictures receiving endoscopic retrograde cholangiography and/or percutaneous transhepatic cholangiodrainage between 2009 and 2015 at the University Medical Center Hamburg-Eppendorf were retrospectively analysed. Potential predictors of long-term success (≥12 months) were identified by univariate and logistic regression analyses. Patient survival was analysed by Kaplan-Meier method and log-rank test., Results: Hundred and sixteen patients were treated with endoscopic retrograde cholangiography and/or percutaneous transhepatic cholangiodrainage, including 67 patients with anastomotic strictures, 22 with nonanastomotic strictures and 27 with both stricture types. Eighty-five patients received endoscopic retrograde cholangiography, 17 percutaneous transhepatic cholangiodrainage and 14 both techniques. Long-term success was achieved in 60 patients (52%). Predictors of treatment failure were a preinterventional C-reactive protein >8 g/dL in anastomotic strictures (P = 0.039) and a body mass index ≤21 kg/m 2 in nonanastomotic strictures (P = 0.021). In patients who received endoscopic retrograde cholangiography only, balloon dilatation of anastomotic strictures with larger diameters favoured success (P = 0.015). Achievement of long-term success was associated with prolonged patient survival in anastomotic strictures (P = 0.036) and nonanastomotic strictures (P = 0.025), but not in combined strictures (P = 0.739)., Conclusion: In post-orthotopic liver transplantation biliary strictures treated by endoscopic retrograde cholangiography and/or percutaneous transhepatic cholangiodrainage, patient BMI and preinterventional C-reactive protein may influence prognosis. Endoscopic retrograde cholangiography with larger balloon diameter may favour success in anastomotic strictures. Long-term success by endoscopic retrograde cholangiography and/or percutaneous transhepatic cholangiodrainage is associated with superior survival in patients with anastomotic strictures and nonanastomotic strictures only., (© 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Enzymatic gas-phase reactions are usually performed in continuous reactors, and thus very stable and active catalysts are required to perform such transformations on cost-effective levels. The present work is concerned with the reduction of gaseous acetophenone to enantiomerically pure (R)-1-phenylethanol catalyzed by solid alcohol dehydrogenase from Lactobacillus brevis (LBADH), immobilized onto glass beads. Initially, the catalyst preparation displayed a half-life of 1 day under reaction conditions at 40 degrees C and at a water activity of 0.5. It was shown that the observed decrease in activity is due to a degradation of the enzyme itself (LBADH) and not of the co-immobilized cofactor NADP. By the addition of sucrose to the cell extract before immobilization of the enzyme, the half-life of the catalyst preparation (at 40 degrees C) was increased 40 times. The stabilized catalyst preparation was employed in a continuous gas-phase reactor at different temperatures (25-60 degrees C). At 50 degrees C, a space-time yield of 107 g/L/d was achieved within the first 80 h of continuous reaction.

Ischemic damage to vital organs supplied by the thoracoabdominal aorta greatly increases the overall risk of aortic dissection. Of 320 patients operated upon for aortic dissection since 1985, 33 (10.3%) underwent operations directed at the relief of malperfusion (15/158 acute type A; 9/18 acute type B; 4/78 chronic type A; 5/66 chronic type B). Organs affected were the kidneys in 32; the bowel in 20; and the spinal cord in 1, while critical lower extremity ischemia was present in 11 patients. In total, 64 vascular areas were affected. Fenestration of the dissecting membrane with or without infrarenal grafting was the procedure performed most frequently in 25, followed by replacement of the descending or thoracoabdominal aorta in 6, and bypass grafting or direct revascularization of individual side branches in 6. Six other operations targeted at the affected organs were done. Twenty-four patients underwent one-stage operation for malperfusion; in 11, early reoperation after primary aortic repair was necessary, while 2 patients were operated electively. Ten of 33 patients died in hospital, 7 of malperfusion-induced complications. Of three late deaths, one was related to sequelae of malperfusion. We conclude that immediate diagnosis and prompt relief of malperfusion offer the best prospects for patient survival. Membrane fenestration appears to be the method of choice for treating malperfusion in most patients, and must be directed to the level of aortic and/or side branch obstruction.