Correlating electronic and magnetic coupling in large magnetic molecules via scanning tunneling microscopy

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Comparison of Life Calculations for Oscillating Bearings Considering Individual Pitch Control in Wind Turbines

The fatigue life calculation of bearings under rotating conditions has been well researched and standardized. In contrast, for bearings in oscillating applications no international standards exist. As a result, pitch bearings in wind turbines are designed with different, non standardized approaches. Furthermore, the impact of individual pitch control on pitch bearings has not yet been studied. In this paper four approaches for fatigue life calculation will be applied and compared under individual pitch control conditions. For comparison, the loads and the bearing geometry of the reference turbine IWT 7.5 MW, which is individual pitch controlled, are used. This paper will show how the bearing life calculated by different approaches reacts to individual pitch control conditions. Furthermore, the factors for the modified rating life, according to the ABMA and ISO standards, which implement different operation conditions on the bearings in rotating applications, are calculated for the given loads and the given bearing geometry in oscillating applications

On the ambiguity of 1,3,2-benzodiazaboroles as donor/acceptor functionalities in luminescent molecules

A series of 1,3-bis(perfluoroaryl)-2-(hetero)aryl-1,3,2-benzodiazaboroles, 1,3-FAr2-2-Ar-1,3,2-N2BC6H4 (Ar = Ph, FAr = C6F5 5; Ar = Ph, FAr = 4-C5F4N 6; Ar = Ph, FAr = 4-NCC6F4 7; Ar = 2-C4H3S, FAr = C6F5 8; Ar = 2-C4H3S, FAr = 4-C5F4N 9; Ar = 2-C4H3S, FAr = 4-NCC6F4 10), were synthesised by cyclocondensation of the adducts PhBBr2·PPh3 or 2-thienylBBr2·PPh3 with N,N′-bis(perfluoroaryl)-o-phenylenediamines in the presence of 2,2,6,6-tetramethylpiperidine. Similar treatments of the PPh3 adducts of 4-(1′,3′-diethyl-1′,3′,2′-benzodiazaborolyl)-phenyldibromoborane with the corresponding diamines gave rise to the push–pull compounds, C6H4(NEt)2B-1,4-C6H4-B(NFAr)2C6H4 (FAr = C6F5 11; 4-C5F4N 12) and C6H4(NEt)2B-2,5-C4H2S-B(NFAr)2C6H4 (FAr = C6F5 13; 4-C5F4N 14). The X-ray structures of 8, 11, 12 and 13 were determined. Electronic structure calculations reveal that the LUMOs are located at the perfluoroaryl groups in 5–14; thus the fluorinated benzodiazaborolyl groups are considered as electron-withdrawing moieties. These moieties differ from alkylated benzodiazaborolyl groups which are regarded as donors. The emission spectra for 5–14 show charge transfer bands with significant solvatochromism and large Stokes shifts (6100–12500 cm−1 in cyclohexane and 8900–15900 cm−1 in CH2Cl2). The emissions of the benzodiazaboroles, 5–10, arise from a different charge transfer (CT) process to the local charge transfer (LCT) process typically found in many fluorescent benzodiazaboroles. This novel remote charge transfer (RCT) process involving the perfluoroaryl groups is supported by CAM-B3LYP computations. The push–pull systems 11–14 here give fluorescent emissions with moderate to high fluorescence quantum yields (65–97%) that arise from the usual LCT process only

PAI-1 secretion of endometrial and endometriotic cells is Smad2/3- and ERK1/2-dependent and influences cell adhesion

In the endometrium transforming growth factor-betas (TGF-ßs) are involved mainly in menstruation and endometriosis. After binding of the ligands to the high-affinity receptors, TGF-ß receptors (TBR1 and TBR2), TGF-ßs activate Smad signaling to modulate gene expression and cellular functions. However, recently also Smad-independent pathways have been studied in more details. To evaluate both pathways, we have analyzed TGF-ß signaling in human endometrial and endometriotic cells. Although endometrial and endometriotic cells secrete TGF-ß1, secretion by stromal cells was higher compared to epithelial cells. In contrast, secretion of TGF-ß2 was higher in endometriotic stromal and endometriotic epithelial cells compared to normal endometrial cells. Treatment of endometrial and endometriotic stromal and epithelial cells with TGF-ß1 or TGF-ß2 increased Smad-dependent secretion of plasminogen activator inhibitor-1 (PAI-1) dramatically in all three cell lines. Of note, endometriotic cells secreted clearly higher levels of PAI-1 compared to endometrial cells. Whereas a TBR1 kinase inhibitor completely blocked the TGF-ß1 or TGF-ß2-induced PAI-1 secretion, an ERK1/2 inhibitor only partially reduced PAI-1 secretion. This inhibition was not dependent on epidermal growth factor receptor (EGFR) activation by phosphorylation but on kinase activity of the TBR1. Finally, treatment of endometrial and endometriotic cell lines with recombinant PAI-1 showed reduced cell adhesion, especially of the endometrial cells. In summary, our results demonstrate that both Smad-dependent and TBR1-dependent ERK1/2 pathways are necessary for TGF-ß-dependent high level secretion of PAI-1, which might increase cellular deadhesion

Non‐target site SDHI resistance is present as standing genetic variation in field populations of Zymoseptoria tritici

BACKGROUND A new generation of more active succinate dehydrogenase (Sdh) inhibitors (SDHIs) is currently widely used to control Septoria leaf blotch in northwest Europe. Detailed studies were conducted on Zymoseptoria tritici field isolates with reduced sensitivity to fluopyram and isofetamid; SDHIs which have only just or not been introduced for cereal disease control, respectively. RESULTS Strong cross‐resistance between fluopyram and isofetamid, but not with other SDHIs, was confirmed through sensitivity tests using laboratory mutants and field isolates with and without Sdh mutations. The sensitivity profiles of most field isolates resistant to fluopyram and isofetamid were very similar to a lab mutant carrying SdhC‐A84V, but no alterations were found in SdhB, C and D. Inhibition of mitochondrial Sdh enzyme activity and control efficacy in planta for those isolates was severely impaired by fluopyram and isofetamid, but not by bixafen. Isolates with similar phenotypes were not only detected in northwest Europe but also in New Zealand before the widely use of SDHIs. CONCLUSION This is the first report of SDHI‐specific non‐target site resistance in Z. tritici. Monitoring studies show that this resistance mechanism is present and can be selected from standing genetic variation in field populations. © 2017 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry

Terretonin N: A New Meroterpenoid from Nocardiopsis sp.

Hamed A, Abdel-Razek AS, Frese M, et al. Terretonin N: A New Meroterpenoid from Nocardiopsis sp. Molecules. 2018;23(2): 299.Terretonin N (1), a new highly oxygenated and unique tetracyclic 6-hydroxymeroterpenoid, was isolated together with seven known compounds from the ethyl acetate extract of a solid-state fermented culture of Nocardiopsis sp. Their structures were elucidated by spectroscopic analysis. The structure and absolute configuration of 1 were unambiguously determined by X-ray crystallography. The isolation and taxonomic characterization of Nocardiopsis sp. is reported. The antimicrobial activity and cytotoxicity of the strain extract and compound 1 were studied using different microorganisms and a cervix carcinoma cell line, respectively

Long-Term Trends and Role of Climate in the Population Dynamics of Eurasian Reindeer

Temperature is increasing in Arctic and sub-Arctic regions at a higher rate than anywhere else in the world. The frequency and nature of precipitation events are also predicted to change in the future. These changes in climate are expected, together with increasing human pressures, to have significant impacts on Arctic and sub-Arctic species and ecosystems. Due to the key role that reindeer play in those ecosystems, it is essential to understand how climate will affect the region's most important species. Our study assesses the role of climate on the dynamics of fourteen Eurasian reindeer (Rangifer tarandus) populations, using for the first time data on reindeer abundance collected over a 70-year period, including both wild and semi-domesticated reindeer, and covering more than half of the species' total range. We analyzed trends in population dynamics, investigated synchrony among population growth rates, and assessed the effects of climate on population growth rates. Trends in the population dynamics were remarkably heterogeneous. Synchrony was apparent only among some populations and was not correlated with distance among population ranges. Proxies of climate variability mostly failed to explain population growth rates and synchrony. For both wild and semi-domesticated populations, local weather, biotic pressures, loss of habitat and human disturbances appear to have been more important drivers of reindeer population dynamics than climate. In semi-domesticated populations, management strategies may have masked the effects of climate. Conservation efforts should aim to mitigate human disturbances, which could exacerbate the potentially negative effects of climate change on reindeer populations in the future. Special protection and support should be granted to those semi-domesticated populations that suffered the most because of the collapse of the Soviet Union, in order to protect the livelihood of indigenous peoples that depend on the species, and the multi-faceted role that reindeer exert in Arctic ecosystems

X-ray photoemission electron microscopy for the study of semiconductor materials

Photoemission Electron Microscopy (PEEM) using X-rays is a novel combination of two established materials analysis techniques--PEEM using UV light, and Near Edge X-ray Absorption Fine Structure (NEXAFS) spectroscopy. This combination allows the study of elemental composition and bonding structure of the sample by NEXAFS spectroscopy with a high spatial resolution given by the microscope. A simple, two lens, 10 kV operation voltage PEEM has been used at the Stanford Synchrotron Radiation Laboratory and at the Advanced Light Source (ALS) in Berkeley to study various problems including materials of interest for the semiconductor industry. In the present paper the authors give a short overview over the method and the instrument which was used, and describe in detail a number of applications. These applications include the study of the different phases of titanium disilicide, various phases of boron nitride, and the analysis of small particles. A brief outlook is given on possible new fields of application of the PEEM technique, and the development of new PEEM instruments

Temporal and structural genetic variation in reindeer (Rangifer tarandus) associated with the pastoral transition in Northwestern Siberia

Funding Information NordForsk. Grant Number: 76915 ERC Advanced Grant. Grant Numbers: 295458, ESRC ES/, M011054/1 JPI HUMANOR ERC Starting GrantPeer reviewedPublisher PD

The diagnostic value of ultrasonography-derived edema of the temporal artery wall in giant cell arteritis: a second meta-analysis

<p>Abstract</p> <p>Background</p> <p>Ultrasonography of temporal arteries is not commonly used in the approach of patients with suspected giant cell arteritis (GCA) in clinical practice. A meta-analysis of primary studies available through April 2004 concluded that ultrasonography could indeed be helpful in diagnosing GCA. We specifically re-examined the diagnostic value of the ultrasonography-derived halo sign, a dark hypoechoic circumferential thickening around the artery lumen, indicating vasculitic wall edema, in GCA.</p> <p>Methods</p> <p>Original, prospective studies in patients with suspected GCA that examined ultrasonography findings of temporal arteries using the ACR 1990 classification criteria for GCA as reference standard, published through 2009, were identified. Only eight studies involving 575 patients, 204 of whom received the final diagnosis of GCA, fulfilled technical quality criteria for ultrasound. Weighted sensitivity and specificity estimates of the halo sign were assessed, their possible heterogeneity was investigated and pooled diagnostic odds ratio was determined.</p> <p>Results</p> <p>Unilateral halo sign achieved an overall sensitivity of 68% (95% CI, 0.61-0.74) and specificity of 91% (95% CI, 0.88-0.94) for GCA. The values of inconsistency coefficient (I²) of both sensitivity and specificity of the halo sign, showed significant heterogeneity concerning the results between studies. Pooled diagnostic odds ratio, expressing how much greater the odds of having GCA are for patients with halo sign than for those without, was 34 (95% CI, 8.21-138.23). Diagnostic odds ratio was further increased to 65 (95% CI, 17.86-236.82) when bilateral halo signs were present (sensitivity/specificity of 43% and 100%, respectively). In both cases, it was found that DOR was constant across studies.</p> <p>Conclusion</p> <p>Temporal artery edema demonstrated as halo sign should be always looked for in ultrasonography when GCA is suspected. Providing that currently accepted technical quality criteria are fulfilled, halo sign's sensitivity and specificity are comparable to those of autoantibodies used as diagnostic tests in rheumatology. Validation of revised GCA classification criteria which will include the halo sign may be warranted.</p