The influence of different diamond spacings in diamond impregnated tools on the wear behavior and material removal

The influence of the spacing of four diamonds on the breakout time and material removal is investigated for a diamond impregnated tool for machining concrete workpieces. A statistical analysis using the Cox-model shows a positive effect of larger spacings on the lifetime of the diamonds where no effect on the material removal can be found. Moreover, a relationship between the position of the diamond and its lifetime is observed

Körperschallanalyse der Ermüdung von Spannbetonbauteilen

Das Ermüdungsversagen von Spannbetonbauteilen mit Spanngliedern aus mehrdrähtigen Litzenbündeln erfolgt i. d. R. drahtweise. Das Brechen solcher einzelner Spanndrähte kann unter Laborbedingungen akustisch sehr gut exakt erfasst werden. Hier wird untersucht, ob das Brechen der Spanndrähte schon kurz vorher akustisch messbar ist. Dies erfolgte über eine Körperschallanalyse mit 512 Frequenzen im Frequenzbereich 0.003 MHz – 1.562 MHz. Wir beschreiben hier eine Analyse-Möglichkeit, identifizieren Probleme dabei und machen Vorschläge für verbesserte zukünftige Analysen. Insbesondere war es von Nachteil, dass nur in einem zweistündigen Takt zweimal pro Stunde nur für ca. Sekunden gemessen werden konnte. Damit konnte kein Zusammenhang zu den Drahtbrüchen festgestellt werden. Allerdings ergab sich ein Zusammenhang zu einem Steifigkeitsparameter

„Hamburger Note zur Digitalisierung des kulturellen Erbes“

Das Recht, insbesondere das Urheberrecht, hat große Auswirkungen darauf, was von dem großen Reichtum unseres kulturellen Erbes im kollektiven Gedächtnis verbleibt. In der digitalen Welt, in der alles Kopie und damit – im urheberrechtlichen Sinne – Vervielfältigung ist, ist auch jede Nutzung des kulturellen Erbes urheberrechtlich relevant. Auf der anderen Seite leben wir in Zeiten einer rasanten Medienentwicklung und eines Überflusses an Informationen, Bildern, Filmen und Texten. Umso größer ist die Herausforderung, die Erinnerung an unser kulturelles Erbe wachzuhalten. Es ist also eine Frage der kulturellen Selbstbehauptung, wie die rechtlichen Rahmenbedingungen für den Umgang mit unserem kulturellen Erbe gesetzt werden. Was nicht online gefunden werden kann, wird zunehmend verschwinden. Insofern können die Auswirkungen eines unausgewogenen Urheberrechts, das das kulturelle Erbe nicht ausreichend berücksichtigt, dramatisch sein. Dieses Buch versammelt verschiedene Vorschläge und Überlegungen, wie die rechtlichen Rahmenbedingungen geändert werden können, um eine stärkere Präsenz auch des urheberrechtlich geschützten kulturellen Erbes im Netz zu ermöglichen. Verfasst sind diese Vorschläge von Experten aus den Gedächtnisinstitutionen sowie aus der Rechtswissenschaft und Politik, mithin von Autoren, die mit den internationalen Rahmenbedingungen und dem urheberrechtlichen Diskurs in Deutschland gut vertraut sind.The law, in particular copyright, has a major impact on what remains in collective memory of the great wealth of our cultural heritage. In the digital world where everything is copy and therefore - in the sense of copyright - reproduction, every use of the cultural heritage is also relevant under copyright law. On the other hand, we live in times of rapid media development and an abundance of information, images, films and texts. This is why the challenge of keeping the memory of our cultural heritage alive is all the greater. It is therefore a question of cultural self-assertion how the legal framework conditions for dealing with our cultural heritage are set. What cannot be found online will increasingly disappear. In this respect, the effects of an unbalanced copyright law that does not take sufficient account of cultural heritage can be dramatic. This book brings together various proposals and reflections on how to change the legal framework in order to increase the presence of copyrighted cultural heritage on the Internet. These proposals are written by experts from memory institutions, law and politics, and thus by authors who are well acquainted with the international framework conditions and copyright discourse in Germany

Quality indicators for patients with traumatic brain injury in European intensive care units

Background: The aim of this study is to validate a previously published consensus-based quality indicator set for the management of patients with traumatic brain injury (TBI) at intensive care units (ICUs) in Europe and to study its potential for quality measur

Changing care pathways and between-center practice variations in intensive care for traumatic brain injury across Europe

Purpose: To describe ICU stay, selected management aspects, and outcome of Intensive Care Unit (ICU) patients with traumatic brain injury (TBI) in Europe, and to quantify variation across centers. Methods: This is a prospective observational multicenter study conducted across 18 countries in Europe and Israel. Admission characteristics, clinical data, and outcome were described at patient- and center levels. Between-center variation in the total ICU population was quantified with the median odds ratio (MOR), with correction for case-mix and random variation between centers. Results: A total of 2138 patients were admitted to the ICU, with median age of 49 years; 36% of which were mild TBI (Glasgow Coma Scale; GCS 13–15). Within, 72 h 636 (30%) were discharged and 128 (6%) died. Early deaths and long-stay patients (> 72 h) had more severe injuries based on the GCS and neuroimaging characteristics, compared with short-stay patients. Long-stay patients received more monitoring and were treated at higher intensity, and experienced worse 6-month outcome compared to short-stay patients. Between-center variations were prominent in the proportion of short-stay patients (MOR = 2.3, p < 0.001), use of intracranial pressure (ICP) monitoring (MOR = 2.5, p < 0.001) and aggressive treatme

ECMO for COVID-19 patients in Europe and Israel

Since March 15th, 2020, 177 centres from Europe and Israel have joined the study, routinely reporting on the ECMO support they provide to COVID-19 patients. The mean annual number of cases treated with ECMO in the participating centres before the pandemic (2019) was 55. The number of COVID-19 patients has increased rapidly each week reaching 1531 treated patients as of September 14th. The greatest number of cases has been reported from France (n = 385), UK (n = 193), Germany (n = 176), Spain (n = 166), and Italy (n = 136) .The mean age of treated patients was 52.6 years (range 16–80), 79% were male. The ECMO configuration used was VV in 91% of cases, VA in 5% and other in 4%. The mean PaO2 before ECMO implantation was 65 mmHg. The mean duration of ECMO support thus far has been 18 days and the mean ICU length of stay of these patients was 33 days. As of the 14th September, overall 841 patients have been weaned from ECMO support, 601 died during ECMO support, 71 died after withdrawal of ECMO, 79 are still receiving ECMO support and for 10 patients status n.a. . Our preliminary data suggest that patients placed on ECMO with severe refractory respiratory or cardiac failure secondary to COVID-19 have a reasonable (55%) chance of survival. Further extensive data analysis is expected to provide invaluable information on the demographics, severity of illness, indications and different ECMO management strategies in these patients

Machine learning algorithms performed no better than regression models for prognostication in traumatic brain injury

Objective: We aimed to explore the added value of common machine learning (ML) algorithms for prediction of outcome for moderate and severe traumatic brain injury. Study Design and Setting: We performed logistic regression (LR), lasso regression, and ridge regression with key baseline predictors in the IMPACT-II database (15 studies, n = 11,022). ML algorithms included support vector machines, random forests, gradient boosting machines, and artificial neural networks and were trained using the same predictors. To assess generalizability of predictions, we performed internal, internal-external, and external validation on the recent CENTER-TBI study (patients with Glasgow Coma Scale <13, n = 1,554). Both calibration (calibration slope/intercept) and discrimination (area under the curve) was quantified. Results: In the IMPACT-II database, 3,332/11,022 (30%) died and 5,233(48%) had unfavorable outcome (Glasgow Outcome Scale less than 4). In the CENTER-TBI study, 348/1,554(29%) died and 651(54%) had unfavorable outcome. Discrimination and calibration varied widely between the studies and less so between the studied algorithms. The mean area under the curve was 0.82 for mortality and 0.77 for unfavorable outcomes in the CENTER-TBI study. Conclusion: ML algorithms may not outperform traditional regression approaches in a low-dimensional setting for outcome prediction after moderate or severe traumatic brain injury. Similar to regression-based prediction models, ML algorithms should be rigorously validated to ensure applicability to new populations

Use and impact of high intensity treatments in patients with traumatic brain injury across Europe: a CENTER-TBI analysis

Abstract: Purpose: To study variation in, and clinical impact of high Therapy Intensity Level (TIL) treatments for elevated intracranial pressure (ICP) in patients with traumatic brain injury (TBI) across European Intensive Care Units (ICUs). Methods: We studied high TIL treatments (metabolic suppression, hypothermia (< 35 °C), intensive hyperventilation (PaCO2 < 4 kPa), and secondary decompressive craniectomy) in patients receiving ICP monitoring in the ICU stratum of the CENTER-TBI study. A random effect logistic regression model was used to determine between-centre variation in their use. A propensity score-matched model was used to study the impact on outcome (6-months Glasgow Outcome Score-extended (GOSE)), whilst adjusting for case-mix severity, signs of brain herniation on imaging, and ICP. Results: 313 of 758 patients from 52 European centres (41%) received at least one high TIL treatment with significant variation between centres (median odds ratio = 2.26). Patients often transiently received high TIL therapies without escalation from lower tier treatments. 38% of patients with high TIL treatment had favourable outcomes (GOSE ≥ 5). The use of high TIL treatment was not significantly associated with worse outcome (285 matched pairs, OR 1.4, 95% CI [1.0–2.0]). However, a sensitivity analysis excluding high TIL treatments at day 1 or use of metabolic suppression at any day did reveal a statistically significant association with worse outcome. Conclusion: Substantial between-centre variation in use of high TIL treatments for TBI was found and treatment escalation to higher TIL treatments were often not preceded by more conventional lower TIL treatments. The significant association between high TIL treatments after day 1 and worse outcomes may reflect aggressive use or unmeasured confounders or inappropriate escalation strategies. Take home message: Substantial variation was found in the use of highly intensive ICP-lowering treatments across European ICUs and a stepwise escalation strategy from lower to higher intensity level therapy is often lacking. Further research is necessary to study the impact of high therapy intensity treatments. Trial registration: The core study was registered with ClinicalTrials.gov, number NCT02210221, registered 08/06/2014, https://clinicaltrials.gov/ct2/show/NCT02210221?id=NCT02210221&draw=1&rank=1 and with Resource Identification Portal (RRID: SCR_015582)