First-principles investigation of spin polarized conductance in atomic carbon wire

We analyze spin-dependent energetics and conductance for one dimensional (1D) atomic carbon wires consisting of terminal magnetic (Co) and interior nonmagnetic (C) atoms sandwiched between gold electrodes, obtained employing first-principles gradient corrected density functional theory and Landauer's formalism for conductance. Wires containing an even number of interior carbon atoms are found to be acetylenic with sigma-pi bonding patterns, while cumulene structures are seen in wires containing odd number of interior carbon atoms, as a result of strong pi-conjugation. Ground states of carbon wires containing up to 13 C atoms are found to have anti-parallel spin configurations of the two terminal Co atoms, while the 14 C wire has a parallel Co spin configuration in the ground state. The stability of the anti-ferromagnetic state in the wires is ascribed to a super-exchange effect. For the cumulenic wires this effect is constant for all wire lengths. For the acetylenic wires, the super-exchange effect diminishes as the wire length increases, going to zero for the atomic wire containing 14 carbon atoms. Conductance calculations at the zero bias limit show spin-valve behavior, with the parallel Co spin configuration state giving higher conductance than the corresponding anti-parallel state, and a non-monotonic variation of conductance with the length of the wires for both spin configurations.Comment: revtex, 6 pages, 5 figure

Four-year stability, change, and multidirectionality of well-being in very-old age

We examined stability, change, and dedifferentiation of well-being in 124 participants with a baseline age between 87 and 97 years (M = 90.56, SD = 2.92) across 7 measurement occasions over 4 years. Measures of hedonic (life satisfaction, positive affect and negative affect) and eudaimonic well-being (autonomy, purpose in life, self-acceptance, environmental mastery), as well as indicators of mental distress (depressive symptoms, attitudes toward death and dying, disease phobia) were included. Average levels indicated high well-being at all measurement occasions in the majority of indicators analyzed. However, mean numbers of depressive symptoms were close to the cutoff point of clinical depression. Analyses of intra-individual correlations revealed high loadings of depressive symptoms, positive affect, and environmental mastery on a common factor. However, several well-being indicators were not substantially interrelated on the intra-individual level, suggesting their trajectories were rather independent of each other. Acceptance of death and dying was surprisingly high and even increased, whereas mean levels in fear of death were very low and declined over time. Overall, our findings do not suggest late-life dedifferentiation of well-being trajectories in very-old age. Our results rather support the need to consider indicators of hedonic and eudaimonic well-being, as well as mental distress, to understand the multifaceted and multidirectional dynamics of well-being in very-old age

Tracing the fate of 15N-labelled animal manure in the environment

Background • Nitrate leaching threatens both the environment and drinking water quality • Switzerland ca. 380,000 ha with > 25 mg nitrate/L in groundwater (quality criteria for drinking water) [1]; the Gäu region (Canton Solothurn) is especially vulnerable • Organic fertilizers (slurry, farmyard manure, etc.) might entail considerably increased leaching risks due to variable nitrogen (N) content and availability • Aim: increase N use efficiency, simultaneously reduce leachin

The key role of topography in altering North Atlantic atmospheric circulation during the last glacial period

The Last Glacial Maximum (LGM; 21 000 yr before present) was a period of low atmospheric greenhouse gas concentrations, when vast ice sheets covered large parts of North America and Europe. Paleoclimate reconstructions and modeling studies suggest that the atmospheric circulation was substantially altered compared to today, both in terms of its mean state and its variability. Here we present a suite of coupled model simulations designed to investigate both the separate and combined influences of the main LGM boundary condition changes (greenhouse gases, ice sheet topography and ice sheet albedo) on the mean state and variability of the atmospheric circulation as represented by sea level pressure (SLP) and 200-hPa zonal wind in the North Atlantic sector. We find that ice sheet topography accounts for most of the simulated changes during the LGM. Greenhouse gases and ice sheet albedo affect the SLP gradient in the North Atlantic, but the overall placement of high and low pressure centers is controlled by topography. Additional analysis shows that North Atlantic sea surface temperatures and sea ice edge position do not substantially influence the pattern of the climatological-mean SLP field, SLP variability or the position of the North Atlantic jet in the LGM

Wireless capsule endoscopy for the detection of small bowel diseases in HIV-1-infected patients

<p>Abstract</p> <p>Background and Aims</p> <p>In HIV-infected patients, manifestations of the disease are common in the gastrointestinal tract. The objective of our study was to evaluate the diagnostic yield of the Given^®Video Capsule System (Given Imaging, Yoqneam, Israel) in these patients.</p> <p>Methods</p> <p>After exclusion of GI-tract stenosis by anamnestic exploration, 49 patients were included into the study. Stratification: Group A (n = 19): HIV-positive, CD₄cell count < 200/μl, gastrointestinal symptoms present. Group B: HIV-positive, CD₄< 200/μl, without gastrointestinal symptoms (n = 19 Group) C: healthy volunteers (n = 11).</p> <p>Results</p> <p>In group A there was a total of 30 pathological findings, 15 of which with therapeutic implications. In group B, there was a total of 22 pathological findings, 5 relevant for therapy. In group C there was a total of 13 pathological findings, 3 with therapeutic relevance. In 89% (group A) vs. 26% (group B), pathological findings were detected distal the ligament of Treitz (p = 0.001). All capsules were recovered without complications after 12 to 96 h from the stool.</p> <p>Conclusion</p> <p>Wireless capsule endoscopy of the small intestine should be considered for HIV-infected patients with marked immunosuppression and gastrointestinal symptoms.</p

Induction of Mutants with Ectopic Expression of Condensed Tannins

Leaves of 47,000 Lotus japonicus plants were screened using a butanol:HCl histochemical test to select “gain of function” mutants. These plants were progeny from L. japonicus lines which were transformed with T-DNA constructs containing either the maize Ds or Ac transposon (Thykjaer et al., 1995). Among 21 putative leaf tannin mutants, five (tan1-5) were characterized for synthesis of condensed tannins, leucocyanidin reductase activity and the presence of Ac and the selectable marker gene, nptII . A range of leaf tannin content among other Lotus species was also characterized

From invasion percolation to flow in rock fracture networks

The main purpose of this work is to simulate two-phase flow in the form of immiscible displacement through anisotropic, three-dimensional (3D) discrete fracture networks (DFN). The considered DFNs are artificially generated, based on a general distribution function or are conditioned on measured data from deep geological investigations. We introduce several modifications to the invasion percolation (MIP) to incorporate fracture inclinations, intersection lines, as well as the hydraulic path length inside the fractures. Additionally a trapping algorithm is implemented that forbids any advance of the invading fluid into a region, where the defending fluid is completely encircled by the invader and has no escape route. We study invasion, saturation, and flow through artificial fracture networks, with varying anisotropy and size and finally compare our findings to well studied, conditioned fracture networks.Comment: 18 pages, 10 figure

Limited Value of Bladder Wash Cytology During Follow-Up of Patients With Non-muscle Invasive Bladder Cancer

Aims We aimed to assess the performance of bladder wash cytology (BWC) in daily clinical practice in a pure follow-up cohort of patients previously diagnosed with non-muscle invasive bladder cancer (NMIBC). Materials and methods We analyzed 2064 BWCs derived from 314 patients followed for NMIBC (2003-2016). Follow-up investigations were performed using cystoscopy (CS) in combination with BWC. Patients with suspicious CS and/or positive BWC underwent bladder biopsy or transurethral resection. BWC was considered positive if malignant or suspicious cells were reported. Sensitivity (Sn) and specificity (Sp) were calculated for the entire cohort and separately for low-grade (LG) and high-grade (HG) tumors, and carcinoma in situ (CIS) subgroups. Results A total of 95 recurrences were detected, of which only three were detected by BWC alone. Overall, Sn and Sp of BWC were 17.9% and 99.5%, respectively. For LG disease, these numbers were 14.0% and 100%, and for HG disease, these were 22.2% and 99.1%, respectively. For patients with CIS at initial diagnosis, Sn and Sp were 11.0% and 71.4%, respectively. For isolated primary CIS, Sn was 50.0%, and Sp was 98.2%. Conclusion Routine use of BWC in the follow-up for NMIBC is of limited value even in HG tumors. In the presence of isolated primary CIS, adjunct BWC might be justified

High expression of Cathepsin E in tissues but not blood of patients with Barrett’s esophagus and adenocarcinoma

Background Cathepsin E (CTSE), an aspartic proteinase, is differentially expressed in the metaplasia–dysplasia–neoplasia sequence of gastric and colon cancer. We evaluated CTSE in Barrett’s esophagus (BE) and cancer because increased CTSE levels are linked to improved survival in several cancers, and other cathepsins are up-regulated in BE and esophageal adenocarcinoma (EAC). Methods A total of 273 pretreatment tissues from 199 patients were analyzed [31 normal squamous esophagus (NE), 29 BE intestinal metaplasia, 31 BE with dysplasia (BE/D), 108 EAC]. CTSE relative mRNA expression was measured by real-time polymerase chain reaction, and protein expression was measured by immunohistochemistry. CTSE serum levels were determined by enzyme-linked immunosorbent assay. Results Median CTSE mRNA expression levels were ≥1,000-fold higher in BE/intestinal metaplasia and BE/D compared to NE. CTSE levels were significantly lower in EAC compared to BE/intestinal metaplasia and BE/D, but significantly higher than NE levels. A similar expression pattern was present in immunohistochemistry, with absent staining in NE, intense staining in intestinal metaplasia and dysplasia, and less intense EAC staining. CTSE serum analysis did not discriminate patient groups. In a uni- and multivariable Cox proportional hazards model, CTSE expression was not significantly associated with survival in patients with EAC, although CTSE expression above the 25th percentile was associated with a 41 % relative risk reduction for death (hazard ratio 0.59, 95 % confidence interval 0.27–1.26, p = 0.17). Conclusions CTSE mRNA expression is up-regulated more than any known gene in Barrett intestinal metaplasia and dysplasia tissues. Protein expression is similarly highly intense in intestinal metaplasia and dysplasia tissues