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We present a model of the electrical resistivity structure of the lithosphere in the Central Andes between 20° and 24°S from 3‐D inversion of 56 long‐period magnetotelluric sites. Our model shows a complex resistivity structure with significant variability parallel and perpendicular to the trench direction. The continental forearc is characterized mainly by high electrical resistivity (>1,000 Ωm), suggesting overall low volumes of fluids. However, low resistivity zones (LRZs, <5 Ωm) were found in the continental forearc below areas where major trench‐parallel faults systems intersect NW‐SE transverse faults. Forearc LRZs indicate circulation and accumulation of fluids in highly permeable fault zones. The continental crust along the arc shows three distinctive resistivity domains, which coincide with segmentation in the distribution of volcanoes. The northern domain (20°–20.5°S) is characterized by resistivities >1,000 Ωm and the absence of active volcanism, suggesting the presence of a low‐permeability block in the continental crust. The central domain (20.5°–23°S) exhibits a number of LRZs at varying depths, indicating different levels of a magmatic plumbing system. The southern domain (23°–24°S) is characterized by resistivities >1,000 Ωm, suggesting the absence of large magma reservoirs below the volcanic chain at crustal depths. Magma reservoirs located below the base of the crust or in the backarc may fed active volcanism in the southern domain. In the subcontinental mantle, the model exhibits LRZs in the forearc mantle wedge and above clusters of intermediate‐depth seismicity, likely related to fluids produced by serpentinization of the mantle and eclogitization of the slab, respectively. Key Points: This paper presents a three-dimensional model of the electrical resistivity structure of the Central Andes subduction zone (20°–24°S)Resistivity of the mantle wedge suggests along‐margin variability in the amount of fluids released by eclogitization of the slabResistivity structure below the arc shows distinctive domains that coincide with segmentation in the distribution of active volcanoes [ABSTRACT FROM AUTHOR]

ABSTRACT The basic physical properties of the magnetic source field, namely its homogeneity and spatial coherence, have been used for a variety of magnetotelluric processing techniques including remote reference processing. In the present work we propose a data acquisition and processing technique for a large number of stations distributed over a localized area ideally on a grid. For pseudo-remote reference processing it is necessary to use the following station setup: five-component MT data are only measured at some sites (base stations) while at the majority of sites (local stations) only the electric and vertical magnetic fields are recorded. The impedance tensor and vertical magnetic transfer functions at each local station are computed by assigning the magnetic fields of a base station to the local station as if they had been measured there. This approach can lead to biased or erroneous estimates of local transfer functions at stations in the vicinity of strong conductivity contrasts that can be corrected using the interstation transfer functions between the horizontal magnetic fields measured at the base station(s). We test this approach with a data set collected in the vicinity of the Groß Schönebeck geothermal test site. Magnetotelluric data were collected at 146 local and 5 base stations distributed over an approximately 5 km × 25 km wide grid with site spacing ranging from 500 m × 500 m to 1000 m × 1000 m in the frequency range 128-0.001Hz. The obtained pseudo-remote reference transfer functions are generally smooth and consistent and conductivity models obtained from 2D inversion of the data are in agreement with previous conductivity models from the study area. [ABSTRACT FROM AUTHOR]

Determining the MR compatibility of medical implants and devices is becoming increasingly relevant. In most cases, the heating of conductive implants due to radiefrequency (RF) excitation pulses is measured by fluoroptic temperature sensors in relevant tests for approval. Another common method to determine these heating effects is MR thermometry using the proton resonance frequency. This method gives good results in homogeneous phantoms. However in many cases, technical shortcomings such as susceptibility artifacts prohibit exact proton resonance frequency thermometry near medical implants. Therefore, this work aimed at developing a fast T1- based method which allows controlled MR-related heating of a medical implant while simultaneously quantifying the spatial and temporal temperature distribution. To this end, an inversion recovery snapshot Fast Low-Angle Shot (FLASH) sequence was modified with additional off-resonant heating pulses. With an accelerated imaging method and a sliding-window technique, every 7.6 s a new temperature map could be generated with a spatial in-plane resolution of 2 mm. The temperature deviation from calculated temperature values to reference fluoroptic probe was found to be smaller than 1 K. [ABSTRACT FROM AUTHOR]

Background and Purpose: Our recent experiments demonstrated that the Sphingosine-1-phosphate (S1P) receptor agonist FTY720 (2-amino-2-[2-(4-octylphenyl)ethyl]-1,3-propanediol hydrochloride) improves recovery of function after myocardial ischaemia-reperfusion ex vivo. Therefore, we tested the hypothesis that pharmacological post-conditioning with FTY720 reduces infarct size after myocardial ischaemia-reperfusion in vivo.Experimental Approach: Myocardial ischaemia was induced in Wistar rats by ligation of the left coronary artery for 45 min. FTY720 (0.5 mg kg(-1)) was applied i.p. either once, before reperfusion, or twice, 24 h before myocardial ischaemia and before reperfusion. After 24 h reperfusion, we determined infarct size by triphenyltetrazolium chloride staining and granulocyte infiltration by immunohistochemistry. Tumour necrosis factor-alpha (TNF)-alpha concentration was determined by elisa. S1P receptor expression was studied by Western blot. Calcium transients were evaluated in Indo-1-loaded cardiomyocytes.Key Results: In both groups, FTY720 significantly reduced lymphocyte count in peripheral blood. FTY720 treatment attenuated granulocyte infiltration and TNF-alpha protein expression in reperfused myocardium. However, both treatment regimens were not able to reduce infarct size. FTY720 increased mortality due to induction of fatal ventricular tachyarrhythmias when administered once before reperfusion, but protected against reperfusion arrhythmias when given 24 h prior to ischaemia. Pretreatment selectively down-regulated S1P(1) receptor expression within the myocardium. S1P receptor agonists did not induce calcium deregulation in cardiomyocytes.Conclusions and Implications: FTY720 applied during reperfusion did not reduce infarct size but increased mortality during myocardial ischaemia-reperfusion due to induction of arrhythmias. Pretreatment with FTY720 before ischaemia abrogated the deleterious pro-arrhythmic effects without reducing infarct size. [ABSTRACT FROM AUTHOR]

An abstract of the article "Stimulation of Myocardial AT2-Rezeptors Increases Calcineurin Activity Via Calpain," by O. Ritter and colleagues is presented.

An abstract of the study "Prohibition of Calcineurin/Importin-Interaction Disrupts Calcineurin/NFAT Cascade," by O. Ritter and colleagues is presented.

An abstract of the study "Conditional Neuronal Nitric Oxide Synthase Overexpression Impairs Myocardial Contractility," by K. Hu and colleagues is presented.

An abstract of the study "Inhibition of nuclear import of calcineurin prevents myocardial hypertrophy," by O. Ritter is presented

Aim: Arteriogenesis constitutes the most efficient endogenous rescue mechanism in cases of cerebral ischaemia. The aim of this work was to investigate whether angiotensin-converting enzyme inhibitors (ACEi) stimulates, and angiotensin II receptor type 1 blockers (ARB) inhibits cerebral collateral growth by applying a three-vessel occlusion (3-VO) model in rat., Methods: Cerebral collateral growth was measured post 3-VO (1) by assessing blood flow using the cerebrovascular reserve capacity (CVRC) technique, and (2) by assessing vessel diameters in the posterior cerebral artery (PCA) via the evaluation of latex angiographies. A stimulatory effect on arteriogenesis was investigated for ACEi administration ± bradykinin receptor 1 (B1R) and 2 (B2R) blockers, and an inhibitory effect was analysed for ARB administration. Results were validated by immunohistochemical analysis and mechanistic data were collected by human umbilical vein endothelial cell (HUVEC) viability or scratch assay and monocyte (THP-1) migration assay., Results: An inhibitory effect of ARB on arteriogenesis could not be demonstrated. However, collateral growth measurements demonstrated a significantly increased CVRC and PCA diameters in the ACEi group. ACEi stimulates cell viability and migration, which could be partially reduced by additional administration of bradykinin receptor 1 inhibitor (B1Ri). ACEi inhibits the degradation of pro-arteriogenic bradykinin derivatives, but combined ACEi + B1Ri + B1Ri (BRB) treatment did not reverse the stimulatory effect. Yet, co-administration of ACEi + BRB enhances arteriogenesis and cell migration., Conclusion: We demonstrate a potent stimulatory effect of ACEi on cerebral arteriogenesis in rats, presumable via B1R. However, results imply a pleiotropic and compensatory effect of ACEi on bradykinin receptor-stimulated arteriogenesis., (© 2021 The Authors. Acta Physiologica published by John Wiley & Sons Ltd on behalf of Scandinavian Physiological Society.)

Objectives: Low emotional intelligence (EI) may predispose individuals to applying maladaptive coping strategies. This may maintain anxious worrying, which is highly prevalent in patients with chronic heart failure (CHF) and may affect mental (MCS) and physical component summaries (PCS) of health-related quality of life (HRQoL)., Design: The current study is a cross-sectional and cross-cultural survey., Methods: N = 200 outpatients with CHF were recruited at cardiology institutes in Germany and Pakistan and assessed with self-report questionnaires., Results: Path analysis (χ 2 (4) = 7.59, p = .11, GFI = .99) revealed that the expected associations between low EI and lower SF-36 MCS and PCS of HRQoL were fully mediated by negative metacognition and maladaptive coping in the Pakistani sample (p's ≤ .05). The German sample applied different maladaptive coping strategies, which also led to lower MCS and PCS scores, but did not mediate a direct positive effect of EI on HRQoL., Conclusion: The current findings support culture-independent validity of the metacognitive model but also reveal major cultural differences regarding the application and effect of specific maladaptive coping strategies. This has important implications for caregivers in a cross-cultural context and highlights the need for culture-specific tailoring of psychosocial interventions. Statement of contribution What is already known on this subject? Worry, an integral component of generalized anxiety disorder (GAD) and highly comorbid in chronic heart failure (CHF) patients, contributes to anxiety and resulting stress as evident from metacognitive model of GAD. In addition, previous literature has also established the protective role of emotional intelligence (EI) against stress, thus maintaining quality of life. What does this study add? Cross-cultural (Pakistan vs. Germany) validation of the metacognitive model of GAD. Supportive evidence for the metacognitive model in patients with CHF. Mediation of maladaptive metacognitions and negative coping in the relationship of low trait EI and low health-related quality of life., (© 2019 The British Psychological Society.)

The Protein Data Bank (PDB) at Brookhaven National Laboratory, is a database containing experimentally determined three-dimensional structures of proteins, nucleic acids and other biological macromolecules, with approximately 8000 entries. Data are easily submitted via PDB's WWW-based tool AutoDep, in either mmCIF or PDB format, and are most conveniently examined via PDB's WWW-based tool 3DB Browser.