•EGS seismicity is compared to wastewater disposal and ultra-deep fluid-injection events.•Near-well and far-field fracturing mechanisms are identified in EGS stimulation.•Recommendations are given to ...safely operate EGS sites (seismic hazard).
In this overview we report results of analysing induced seismicity in geothermal reservoirs in various tectonic settings within the framework of the European Geothermal Engineering Integrating Mitigation of Induced Seismicity in Reservoirs (GEISER) project. In the reconnaissance phase of a field, the subsurface fault mapping, in situ stress and the seismic network are of primary interest in order to help assess the geothermal resource. The hypocentres of the observed seismic events (seismic cloud) are dependent on the design of the installed network, the used velocity model and the applied location technique. During the stimulation phase, the attention is turned to reservoir hydraulics (e.g., fluid pressure, injection volume) and its relation to larger magnitude seismic events, their source characteristics and occurrence in space and time. A change in isotropic components of the full waveform moment tensor is observed for events close to the injection well (tensile character) as compared to events further away from the injection well (shear character). Tensile events coincide with high Gutenberg-Richter b-values and low Brune stress drop values. The stress regime in the reservoir controls the direction of the fracture growth at depth, as indicated by the extent of the seismic cloud detected. Stress magnitudes are important in multiple stimulation of wells, where little or no seismicity is observed until the previous maximum stress level is exceeded (Kaiser Effect). Prior to drilling, obtaining a 3D P-wave (Vp) and S-wave velocity (Vs) model down to reservoir depth is recommended. In the stimulation phase, we recommend to monitor and to locate seismicity with high precision (decametre) in real-time and to perform local 4D tomography for velocity ratio (Vp/Vs). During exploitation, one should use observed and model induced seismicity to forward estimate seismic hazard so that field operators are in a position to adjust well hydraulics (rate and volume of the fluid injected) when induced events start to occur far away from the boundary of the seismic cloud.
The dentist's main working area is the head and neck region, which is innervated by the cranial nerves. On a daily basis, dentists must administer local anaesthesia to ensure pain-free treatment and ...differentiate between dental pain and neuropathies to avoid mistreatment. Therefore, neuroanatomical training, especially on the cranial nerves, is of immense importance for clinical practice. In order to adopt the curriculum, it is essential to constantly evaluate the quality of the training and to investigate whether there is a correlation between the students' performance and the relevance of the subfields to their work.
To address this issue, the results of MC exams in the neuroanatomy course for dental students at Charité-Universitätsmedizin Berlin from winter semester 2014/2015 to winter semester 2019/2020 were analysed. Each question was assigned to a specific subfield of neuroanatomy. We then compared cranial nerves and cranial nerve nuclei (clinically relevant) with the remaining subfields (clinically less/not relevant) to investigate whether students performed better in anatomy subfields that are more aligned with the clinical practice of a dentist. We also conducted an anonymous survey (n=201) of the dental students.
From winter semester 2014/2015 to winter semester 2019/2020, students performed significantly (***, p< 0.001) better on the clinically relevant questions of the MC examination than on the less/not clinically relevant questions. However, when looking at each of the eleven semesters separately, only three semesters actually performed significantly better on the clinically relevant questions. Our survey also showed that students perceived the subfield of cranial nerves and cranial nerve nuclei to be the most relevant and studied it more intensively out of their own interest.
The study showed that students perceived the subfield of cranial nerves and cranial nerve nuclei to be the most relevant. However, there was no direct correlation between student performance and clinically relevant questions. Using student performance alone as an indicator of relevance is not optimal, as factors such as motivation to learn can have a significant impact.
Greater clinical relevance influences what students learn more intensively out of their own interest, but does not influence the results of the MC examination in favour of the subspecialty. Based on the available evidence, it is recommended that the structure of the neuroanatomy course be reconsidered.
Change in body weight during the COVID-19 pandemic as an unintended side effect of lockdown measures has been predominantly reported for younger and middle-aged adults. However, information on older ...adults for which weight loss is known to result in adverse outcomes, is scarce. In this study we describe the body weight change in older adults before, during, and after the COVID-19 lockdown measures and explore putative associated factors with a focus on the period that includes the first six months of the COVID-19 containment measures.
Prospective cohort study with three follow-up examinations over the course of 10 years.
In this study, we analyzed the longitudinal weight change of 472 participants of the Berlin Aging Study II (mean age of 67.5 years at baseline).
Body weight was assessed at four time points. Additionally, differences between subgroups characterized by socio-economic, cognitive, and psychosocial variables as well as morbidity burden, biological age markers (epigenetic clocks, telomere length), and frailty were compared.
On average, women and men lost 0.87% (n = 227) and 0.5% (n = 245) of their body weight per year in the study period covering the first six months of the COVID-19 pandemic. Weight loss among men was particularly pronounced among groups characterized by change in physical activity due to COVID-19 lockdown, low positive affect, premature epigenetic age (7-CpG clock), diagnosed metabolic syndrome, and a more masculine gender score (all variables: p < 0.05, n = 245).
During the COVID-19 pandemic, older participants lost weight with a 2.5-times (women) and 2-times (men) higher rate than what is expected in this age.
•A relative significance analysis tool to assess solute transport in streams.•Analyzing process signatures on a concentration cloud of solute.•Consistent assessment of longitudinal dispersion and ...transient storage.
Solute transport in rivers is controlled by surface flow hydrodynamics and by transient storage in dead zones, pockets of vegetation and hyporheic sediments where mass exchange and retention are governed by complex mechanisms. The physics of these processes are generally investigated by optimization of transient storage models (TSMs) to experimental data often yielding inconsistent and equifinal parameter sets. Uncertainty on parameters estimation is found to depend not only on the rates of exchange between the stream and storage zones, the stream-water velocity and the stream reach length according to the experimental Damkohler number (DaI), but also on the relative significance between transient storage and longitudinal dispersion on breakthrough curves (BTCs). An optimization strategy was developed and applied to an experimental dataset obtained from tracer tests in a small lowland river, analyzing BTCs generated through tracer injections under different conditions. The method supplies a tool to estimate model parameters from observed data through the analysis of the relative parameter significance. To analyze model performance a double compartment TSM was optimized by a regular fit procedure based on simple root mean square error minimization and by a fit based on a relative significance analysis of mechanism signatures. As a result consistent longitudinal dispersion and transient storage parameters were obtained when the signature targeted optimization was used.
Um 1900 entwickelte die Heimatschutzbewegung aus dem Volkstumsdiskurs heraus eine identitätspolitische Spielart der Moderne, die eine eigene Architekturprogrammatik einschloss. Rainer Schmitz ...untersucht deren Entstehung und Konzeption durch Akteure des 1904 gegründeten »Bundes Heimatschutz« wie Ernst Rudorff, Paul Schultze-Naumburg oder Otto March. Im Fokus seiner Sondierungen steht die Übersetzung gesellschaftlicher Konstrukte und Phänomene wie der »sozialen Frage«, Heimat, Volkstum oder Antisemitismus in den Baudiskurs sowie deren Architektonisierung in Projekten wie den Nationalstadien oder der »deutschen Ostkolonisation«. Damit trägt er u.a. zur Debatte über die Konstruktion kollektiver Identitäten bei.
This paper reviews the development and establishment of the Berlin Heart EXCOR® (BHE®) as a paediatric mechanical circulatory support and reports our entire experience with regard to indications, ...timing of implantation and explantation and outcome. The Berlin group reported the first successful paediatric bridge to transplantation using a pulsatile pneumatic paracorporeal biventricular assist device, the BHE®, in 1990 in an 8-year-old boy with end-stage heart failure and coarctation of the aorta. This experience prompted them to develop miniaturized pump systems for children through the company Berlin Heart Mediproduct GmbH. The development and production of BHE® to support paediatric patients with heart failure then began. Between 1990 and 2013, the BHE® has been implanted in 122 patients (median age 8.64 years, range 3 days to 17 years) with heart failure, who were inotrope-dependent or switched from extracorporeal membrane oxygenation support or had postcardiotomy low-output syndrome. Thirty-five patients were <1 year old (median 125 days). The aetiology of heart failure included cardiomyopathy in 56 (median age 9.14 years), fulminant myocarditis in 17 (median age 8.2 years), end-stage congenital heart disease in 18 (median age 6.4 years), postcardiotomy heart failure (after correction of congenital heart disease) in 28 (median age 9.6 years) and transplant graft failure in 3 (median age 12.5 years). The overall median duration of implantation was 63.6 (range 1–841) days. Fifty-six children eventually underwent orthotopic heart transplantation. Eighteen patients had myocardial recovery and were weaned successfully. They had entirely normal cardiac function after a range of 4–10 years after surgery. At the time of this report, five patients were still on support, with a duration of 354–369 days. Forty-three patients died on the system from loss of peripheral circulatory resistance, multiorgan damage, sepsis or haemorrhagic or thrombotic complications. Re-exploration because of bleeding was necessary in 22 patients. Pump exchange because of thrombus formation in the valves was necessary 35 times. With the introduction of a modified anticoagulation regimen in 2000, the pump exchange rate has decreased. The BHE® can reliably support the circulation at any age for long periods with good results. It is now an established treatment for children with heart failure of any aetiology.
Purpose
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has spread worldwide causing a global health emergency. Pa-COVID-19 aims to provide comprehensive data on clinical course, ...pathophysiology, immunology and outcome of COVID-19, to identify prognostic biomarkers, clinical scores, and therapeutic targets for improved clinical management and preventive interventions.
Methods
Pa-COVID-19 is a prospective observational cohort study of patients with confirmed SARS-CoV-2 infection treated at Charité - Universitätsmedizin Berlin. We collect data on epidemiology, demography, medical history, symptoms, clinical course, and pathogen testing and treatment. Systematic, serial blood sampling will allow deep molecular and immunological phenotyping, transcriptomic profiling, and comprehensive biobanking. Longitudinal data and sample collection during hospitalization will be supplemented by long-term follow-up.
Results
Outcome measures include the WHO clinical ordinal scale on day 15 and clinical, functional, and health-related quality-of-life assessments at discharge and during follow-up. We developed a scalable dataset to (i) suit national standards of care, (ii) facilitate comprehensive data collection in medical care facilities with varying resources, and (iii) allow for rapid implementation of interventional trials based on the standardized study design and data collection. We propose this scalable protocol as blueprint for harmonized data collection and deep phenotyping in COVID-19 in Germany.
Conclusion
We established a basic platform for harmonized, scalable data collection, pathophysiological analysis, and deep phenotyping of COVID-19, which enables rapid generation of evidence for improved medical care and identification of candidate therapeutic and preventive strategies. The electronic database accredited for interventional trials allows fast trial implementation for candidate therapeutic agents.
Trial registration
Registered at the German registry for clinical studies (DRKS00021688)
Stroke is the most feared complication associated with the Berlin Heart EXCOR pediatric ventricular assist device (VAD), the most commonly used VAD in children, and affects 1 in 3 children. We sought ...to determine whether a modified anti-thrombotic guideline, involving more intense platelet inhibition and less reliance on platelet function testing, is associated with a lower incidence of stroke.
All children supported with the EXCOR at Stanford from 2009 to 2014 were divided into 2 cohorts based on the primary anti-thrombotic guideline used to prevent pump thrombosis: (1) the Edmonton Anti-thrombotic Guideline (EG) cohort, which included children implanted before September 2012 when dual anti-platelet therapy was used with doses titrated to Thromboelastrography/PlateletMapping (TEG/PM); and (2) the Stanford Modified Anti-thrombotic Guideline (SG) cohort, which included children implanted on or after September 2012 when triple anti-platelet therapy was used routinely and where doses were uptitrated to high, weight-based dosing targets, with low-dose steroids administered as needed for inflammation.
At baseline, the EG (N = 16) and SG (N = 11) cohorts were similar. The incidence rate of stroke in the SG cohort was 84% lower than in the EG cohort (0.8 vs 4.9 events per 1,000 days of support, p = 0.031), and 86% lower than in the previous Investigational Device Exemption trial (p = 0.006). The bleeding rate was also lower in the SG cohort (p = 0.015). Target doses of aspirin, clopidogrel and dipyridamole were higher (all p < 0.003), with less dosing variability in the SG cohort than in the EG cohort. There was no difference in adenosine diphosphate inhibition by TEG/PM, but arachidonic acid inhibition was higher in the SG cohort (median 75% vs 39%, p = 0.008).
Stroke was significantly less common in pediatric patients supported with the Berlin Heart EXCOR VAD using a triple anti-platelet regimen uptitrated to high, weight-based dosing targets as compared with the dual anti-platelet regimen titrated to PM, and without a higher risk of bleeding. Larger studies are needed to confirm these findings.
Exploiting imaging spectrometer data with machine learning algorithms has been demonstrated to be an excellent choice for mapping ecologically meaningful land cover categories in spectrally complex ...urban environments. However, the potential of kernel-based regression techniques for quantitatively analyzing urban composition has not yet been fully explored. To a great extent, this can be explained by difficulties in deriving quantitative training information that reliably represents pairs of spectral signatures with associated land cover fractions needed for empirical modeling. In this paper we present an approach to circumvent this limitation by combining support vector regression (SVR) with synthetically mixed training data to map sub-pixel fractions of single urban land cover categories of interest. This approach was tested on Hyperspectral Mapper (HyMap) data acquired over Berlin, Germany. Fraction estimates were validated with extensive manual mappings and compared to fractions derived from multiple endmember spectral mixture analysis (MESMA). Our regression results demonstrate that the sets of multiple mixtures yielded high accuracies for quantitative estimates for four spectrally complex urban land cover types, i.e., fractions of impervious rooftops and pavements, as well as grass- and tree-covered areas. Despite the extrapolation uncertainty of SVR, which resulted in fraction values below 0% and above 100%, physically meaningful model outputs were reported for a clear majority of pixels, and visual inspection underpinned the quality of produced fraction maps. Statistical accuracy assessment with detailed reference information for 92 urban blocks showed linear relations with R2 values of 0.86, 0.58, 0.81 and 0.85 for the four categories, respectively. Mean absolute errors (MAE) ranged from 6.4 to 12.8% and block-wise sums of the four individually modeled category fractions were always around 100%. Results of MESMA followed similar trends, but with slightly lower accuracies. Our findings demonstrate that the combination of SVR and synthetically mixed training data enable the use of empirical regression for sub-pixel mapping. Thus, the strengths of kernel-based approaches for quantifying urban land cover from imaging spectrometer data can be well utilized. Remaining uncertainties and limitations were related to the known phenomena of spectral similarity or ambiguity of urban materials, the spectral deficiencies in shaded areas, or the dependency on comprehensive and representative spectral libraries. Therefore, the suggested workflow constitutes a new flexible and extendable universal modeling approach to map land cover fractions.
•We used HyMap data and SVR to quantify spectrally complex urban land cover types.•We trained SVR models with synthetically mixed data.•We compared our results to fraction maps derived from MESMA.•Our approach yields high accuracies and improves fraction estimates.•Our approach enables the use of empirical regression for sub-pixel mapping.
Because of the high prevalence of obstructive sleep apnea (OSA) and its adverse impact on perioperative outcome, a practical screening tool for surgical patients is required. This study was conducted ...to validate the Berlin questionnaire and the American Society of Anesthesiologists (ASA) checklist in surgical patients and to compare them with the STOP questionnaire.
After hospital ethics approval, preoperative patients aged 18 yr or older and without previously diagnosed OSA were recruited. The scores from the Berlin questionnaire, ASA checklist, and STOP questionnaire were evaluated versus the apnea-hypopnea index from in-laboratory polysomnography. The perioperative data were collected through chart review.
Of 2,467 screened patients, 33, 27, and 28% were respectively classified as being at high risk of OSA by the Berlin questionnaire, ASA checklist, and STOP questionnaire. The performance of the screening tools was evaluated in 177 patients who underwent polysomnography. The sensitivities of the Berlin questionnaire, ASA checklist, and STOP questionnaire were 68.9-87.2, 72.1-87.2, and 65.6-79.5% at different apnea-hypopnea index cutoffs. There was no significant difference between the three screening tools in the predictive parameters. The patients with an apnea-hypopnea index greater than 5 and the patients identified as being at high risk of OSA by the STOP questionnaire or ASA checklist had a significantly increased incidence of postoperative complications.
Similar to the STOP questionnaire, the Berlin questionnaire and ASA checklist demonstrated a moderately high level of sensitivity for OSA screening. The STOP questionnaire and the ASA checklist were able to identify the patients who were likely to develop postoperative complications.
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