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The Late Middle and Early Upper Palaeolithic in Crimea (Ukraine)—A Review of the Neanderthal Refugium Hypothesis
Get PDFThe Crimean Peninsula contains numerous important Palaeolithic sites. It has been considered a potential Neanderthal refugium in Eurasia prior to their disappearance or assimilation, and subsequent replacement by Homo sapiens . This understanding is primarily drawn from lithic technological analysis and radiocarbon dating. However, recent developments in the latter suggest that many of the previously obtained radiocarbon dates from Crimean sites may be too young. The chronological sequence from the site of Kabazi II is a case in point, where differences between dates of bulk collagen and those of single amino acids range up to 10,000 radiocarbon years. These discrepancies are argued to arise from sample contamination and its lack of removal in bulk collagen dating. In this paper, we undertake a critical re-evaluation of results from seven Palaeolithic archaeological sites in the Crimean Peninsula: Kabazi II, Siuren I, Buran-Kaya III, Zaskalnaya V and Zaskalnaya VI, Kabazi V and Starosel’e. Our analysis of radiocarbon results from various sites supports the view that radiocarbon dates obtained so far tend to be too young, which has been indicated in the stratigraphy and lithic assemblages. By harnessing robust radiocarbon protocols in future chronometric work, such as the extraction of hydroxyproline, ninhydrin derivatisation or the purification of amino acids using XAD-2 resin, there is potential for constructing accurate chronologies. Furthermore, improved dating accuracy holds the promise of significant additional insights into the prehistoric sequence of the Crimean Peninsula and its potential role as a refugium for Neanderthals prior to their disappearance.Open access funding provided by University of Vienna.University of Vienn
A surgical activity model of laparoscopic cholecystectomy for co-operation with collaborative robots
Get PDFBackground Laparoscopic cholecystectomy is a very frequent surgical procedure. However, in an ageing society, less surgical staff will need to perform surgery on patients. Collaborative surgical robots (cobots) could address surgical staff shortages and workload. To achieve context-awareness for surgeon-robot collaboration, the intraoperative action workflow recognition is a key challenge. Methods A surgical process model was developed for intraoperative surgical activities including actor, instrument, action and target in laparoscopic cholecystectomy (excluding camera guidance). These activities, as well as instrument presence and surgical phases were annotated in videos of laparoscopic cholecystectomy performed on human patients ( n = 10) and on explanted porcine livers ( n = 10). The machine learning algorithm Distilled-Swin was trained on our own annotated dataset and the CholecT45 dataset. The validation of the model was conducted using a fivefold cross-validation approach. Results In total, 22,351 activities were annotated with a cumulative duration of 24.9 h of video segments. The machine learning algorithm trained and validated on our own dataset scored a mean average precision (mAP) of 25.7% and a top K = 5 accuracy of 85.3%. With training and validation on our dataset and CholecT45, the algorithm scored a mAP of 37.9%. Conclusions An activity model was developed and applied for the fine-granular annotation of laparoscopic cholecystectomies in two surgical settings. A machine recognition algorithm trained on our own annotated dataset and CholecT45 achieved a higher performance than training only on CholecT45 and can recognize frequently occurring activities well, but not infrequent activities. The analysis of an annotated dataset allowed for the quantification of the potential of collaborative surgical robots to address the workload of surgical staff. If collaborative surgical robots could grasp and hold tissue, up to 83.5% of the assistant’s tissue interacting tasks (i.e. excluding camera guidance) could be performed by robots.Open access funding enabled and organized by Projekt DEAL.Open Access funding enabled and organized by Projekt DEAL.Bundesministerium für Bildung und Forschunghttp://dx.doi.org/10.13039/501100002347Deutsche Forschungsgemeinschafthttp://dx.doi.org/10.13039/501100001659Technische Universität Dresden (1019
Two-dye two-color laser-induced fluorescence spectroscopy on droplets of green solvent water/ethanol mixtures for thermometry and mixture composition
Get PDFThis work shows new insights on the application of two-color laser-induced-fluorescence (2c-LIF) thermometry in a droplet chain. A two-dye mixture is used in ethanol, water and ethanol/water mixtures in order to reach a high-temperature sensitivity and avoid the detection of lasing effects in the droplets. Various droplet sizes are recorded in regard to the limitation of the detection system for very small micrometric droplets. The breakup of a droplet chain is measured to assess the spectral detection system in applications with liquid structures of different sizes. Additionally, a proposal to expand the 2c-LIF application for studying ethanol/water droplets regarding mixture composition with a third color channel is presented. Forming two intensity ratios, the spectra can be used to obtain information on the mixture composition of the solvent. Measurements in different ethanol/water mixtures containing 0–100 vol% water are evaluated to show this possibility.Open Access funding enabled and organized by Projekt DEAL.Universität der Bundeswehr München (3147
Uncertainty in determining the optimal test duration for maximal rate of lactate accumulation during all‐out sprint cycle ergometry
Get PDFOpen Access funding enabled and organized by Projekt DEAL.Julius-Maximilians-Universität Würzburg (3088
Interdiffusion Coefficients and Strengthening Effects of Nb, Ta, and Zr in the α2-Ti3Al Phase
Get PDFThe creep properties of fully lamellar γ/α2 titanium aluminides can be significantly improved by alloying with Nb, Ta or Zr. While the influence of these alloying elements on the γ-phase has already been examined, their diffusivity and strengthening properties in the α2-phase are still lacking. In order to study the effect of Nb, Ta and Zr in α2-Ti3Al, the alloys Ti-33Al, Ti-33Al-5Nb, Ti-33Al-5Ta and Ti-33Al-5Zr were investigated using a diffusion couple approach and strain rate jump tests. The results show that Zr diffuses the fastest, followed by Nb and Ta. Furthermore, these alloying elements also increase the strength compared to a binary Ti-33Al alloy, from which Zr leads to the highest strength increase followed by Ta and Nb. The lower diffusivity of Ta becomes increasingly important at higher temperatures and lower strain rates resulting in a higher strengthening potential than Nb and Zr under such conditions.Open Access funding enabled and organized by Projekt DEAL.Friedrich-Alexander-Universität Erlangen-Nürnberg (1041
Integrating artificial intelligence with expert knowledge in global environmental assessments: opportunities, challenges and the way ahead
Get PDFWith new cycles of global environmental assessments (GEAs) recently starting, including GEO-7 and IPCC AR7, there is increasing need for artificial intelligence (AI) to support in synthesising the rapidly growing body of evidence for authors and users of these assessments. In this article, we explore recent advances in AI and connect them to the different stages of GEAs showing how some processes can be automatised and streamlined. The meticulous and labour-intensive nature of GEAs serves as both a valuable strength and a challenge to staying pertinent and current in today’s era of urgency and the pursuit of the latest knowledge. Utilising AI tools for reviewing and synthesizing scientific literature holds the evident promise of substantially lessening the workload for experts and expediting the assessment process. This, in turn, could lead to more frequent report releases and a smoother integration of the latest scientific advancements into actionable measures. However, successful outcomes can only be achieved if domain experts co-develop and oversee the deployment of such tools together with AI researchers. Otherwise, these tools run the risk of producing inaccurate, incomplete, or misleading information with significant consequences. We demonstrate this through a few examples that compare recently deployed large language models (LLMs) based tools in their performance in capturing nuanced concepts in the context of the reports of the Intergovernmental Panel on Climate Change (IPCC). We recommend establishing ethical committees and organising dedicated expert meetings to develop best practice guidelines, ensuring responsible and transparent integration of AI into GEAs.Open access funding provided by University of ZurichUniversity of Zuric
„Tracking Ulcus digital-vital“ - Mobilität, Schmerzniveau und Schlafqualität von Patienten mit Ulcus cruris venosum
Get PDFHintergrund und Ziele
Das Ziel dieser Arbeit war es, das Ausmaß der Mobilität, das Schmerzniveau und die Schlafqualität von Patienten mit venösen Beingeschwüren mit alters- und geschlechtsadaptierten Kontrollpersonen ohne chronische Wunden zu vergleichen. Darüber hinaus wurde der Einfluss von Alter, Body-Mass-Index (BMI), Short-Physical Performance Battery (SPPB) und Dauer körperlicher Outdoor-Aktivitäten auf die Gesamtschrittzahl in beiden Gruppen untersucht.
Methoden
Zwanzig Patienten mit venösen Beingeschwüren und zwanzig Kontrollpersonen trugen jeweils eine Smartwatch (Huawei Watch GT), die über einen Zeitraum von einer Woche die Anzahl der Schritte, die zurückgelegte Distanz, die Herzfrequenz und die Schlafdauer aufzeichnete. Zusätzlich wurden ein Fragebogen, körperliche Tests und ein Probandentagebuch verwendet, um die Mobilität, die Schmerzintensität und den Schlaf in beiden Gruppen zu erfassen.
Ergebnisse
Die medianen täglichen Schrittzahlen der Ulcusgruppe (3622 Schritte/Tag [Bereich: 672 – 9091 Schritte/Tag]) und der Kontrollgruppe (5133 Schritte/Tag [Bereich: 1206 – 14304 Schritte/Tag]) unterschieden sich signifikant (Mann -Whitney-U-Test: U = 112.000; Z = -2.380; p = .017). In der Ulcusgruppe wurden signifikante Korrelationen zwischen der Gesamtschrittzahl und dem Alter, der Dauer der angegebenen körperlichen Outdoor-Aktivitäten und dem SPPB-Score beobachtet. Obwohl die Gesamtschrittzahl eine signifikante Korrelation zum BMI in der Kontrollgruppe aufwies (rs = -0,677; p = 0,001), zeigte sich kein Zusammenhang zwischen dem BMI und der Gesamtschrittzahl in der Ulcusgruppe (rs = 0,385; p =.094). Die Ergebnisse der SPPB unterschieden sich in beiden Gruppen signifikant (Mann-Whitney-U-Test: U = 96.000; p = .005), was auf eine verminderte körperliche Leistungsfähigkeit in der Ulcusgruppe hinweist. Der größte Unterschied der anamnestisch angegeben Schmerzstärke, bewertet anhand der numerischen Rating-Skala (NRS), zwischen der Ulcusgruppe (NRS = 5,3 ± 2,7) und der Kontrollgruppe (NRS = 2,6 ± 2,5) zeigte sich während der Bewegung. Im Durchschnitt schlief die Ulcusgruppe um 1 Stunde und 38 Minuten kürzer (Mann-Whitney-U-Test: U = 85.000; p = .002) und hatte 0,7 Wachphasen pro Nacht (Mann-Whitney-U-Test: U = 119.000; p = .019) mehr als die Kontrollgruppe. Die Ergebnisse der vorliegenden Arbeit wurden veröffentlicht von Michael Siegling, Prof. Dr. med. Regina Renner und PD Dr. med. Cornelia Erfurt-Berge unter dem Titel „Mobility range, level of pain and sleep quality of patients with venous leg ulcers.“ im International Wound Journal am 20 April 2023, auffindbar unter: doi: 10.1111/iwj.14195.
Schlussfolgerungen
Teilnehmende mit venösen Beingeschwüren sind im Vergleich zu einer alters- und geschlechtsadaptierten Kontrollgruppe deutlich in ihrer Mobilität eingeschränkt. In unserer Studie zeigten sich bei Patienten mit venösen Beingeschwüren eine deutlich kleinere mediane Schrittzahl pro Tag, eine verringerte körperliche Leistungsfähigkeit, eine höhere Schmerzintensität sowie eine verringerte Schlafdauer und -qualität
Postnatal management of preterm infants with spinal muscular atrophy: experience from German newborn screening
Get PDFBackground The introduction of newborn screening (NBS) for spinal muscular atrophy (SMA) has increased the early diagnosis of 5q-associated SMA in presymptomatic and symptomatic preterm infants. National and international recommendations for treating preterms and newborns < 38 weeks of gestational age are unavailable. Our retrospective multicentre study aimed to evaluate the postnatal clinical course of preterm infants with 5q-associated SMA diagnosed since the implementation of NBS in Germany in 2021 and to summarize the German experience regarding the decision-making process for available treatment regimens for preterm infants with ≤ 3 survival of motor neuron 2 ( SMN2 ) copies. Results Twelve preterm infants with 5q-associated SMA and a mean gestational age of 34.0 weeks (range: 26.1–36.8) and birth weight of 2022 g (range: 645–3370) were reported from 8/20 German SMA NBS follow-up centers using a pseudonymized questionnaire. Confirmatory diagnosis, including SMN2 copy number, was completed on average on postnatal day 13. All patients had a biallelic deletion of exon 7 or exons 7 and 8 of the survival of motor neuron 1 ( SMN1 ) gene, with SMN2 copy numbers of two in 10 patients and three in two patients. The neonatal course was complicated by respiratory distress due to prematurity ( n = 2), sepsis ( n = 2), and jaundice ( n = 2). At birth, 11 preterm infants (91.6%) were presymptomatic. However, the neurological status of one patient deteriorated at five weeks of age (postconceptional age of 41.8 weeks) prior to the start of treatment. Disease-modifying treatments were initiated in all patients at a mean postconceptional age of 38.8 weeks, with the majority receiving onasemnogene abeparvovec (83.3%, including 2 patients with prior risdiplam bridge therapy). Notably, consensus among participating experts from German neuromuscular centers resulted in 83.3% of patients receiving disease-modifying treatment at term. Conclusions Premature infants with SMA require interdisciplinary care in close collaboration with the neuromuscular center. SMA NBS facilitates early initiation of disease-modifying therapy, ideally during the presymptomatic phase, which significantly influences the prognosis of the newborn.Open Access funding enabled and organized by Projekt DEAL.Universitätsklinikum Erlangen (8546
Workplace-related stress experience and mental health of healthcare workers during the COVID-19 pandemic: risk and protective factors from the VOICE study
No full textZusammenfassung Hintergrund Beschäftigte im Gesundheitswesen haben ein erhöhtes Risiko für Depressionen und Angstsymptome und insbesondere während der COVID-19-Pandemie war medizinisches Personal vielseitig gefordert. Ziel der VOICE-Studie war es, Risiko- und Schutzfaktoren für arbeitsplatzbezogenes Belastungserleben und psychische Gesundheit zu untersuchen. Methode Im Verbund von 5 psychosomatischen Universitätskliniken (Erlangen, Ulm, Bonn, Köln und Dresden) wurde ab Frühjahr 2020 eine multizentrische, webbasierte und prospektive Befragung (VOICE-Studie) initiiert. An der Studie nahmen zu 5 Messzeitpunkten mehr als 25.000 Personen teil. Ergebnisse Von 3678 während der ersten Pandemiewelle untersuchten Mitarbeitenden im Krankenhaussetting waren 17,4 % bzw. 17,8 % der Ärztinnen und Ärzte, 21,6 % bzw. 19,0 % der Pflegekräfte und 23,0 % bzw. 20,1 % der medizinisch-technischen Assistenteninnen und Assistenten (MTA) von Depressions- und Angstsymptomen in klinisch relevantem Ausmaß betroffen. Die wichtigsten Risikofaktoren für eine depressive bzw. Angstsymptomatik waren unzureichende Erholung in der Freizeit, erhöhter Alkoholkonsum, geringeres Vertrauen in die Kolleginnen und Kollegen in schwierigen Arbeitssituationen sowie erhöhte Angst, sich mit COVID-19 zu infizieren. Prädiktoren für eine erhöhte posttraumatische Symptomatik waren erhöhte generalisierte Angst und Depressivität sowie erhöhte Angst vor Ansteckung der Angehörigen. Als protektive Faktoren fungierten Kohärenzgefühl, soziale Unterstützung, Optimismus und Belohnungsniveau. Diskussion Die psychischen Auswirkungen arbeitsplatzbezogener Belastung in der Pandemie stellten sich als bedeutsam dar. Daher sind regelmäßige Screening- und Präventionsprogramme zur psychischen Gesundheit für Beschäftigte im Gesundheitswesen angezeigt.Background Healthcare workers have an increased risk of depression and anxiety, and medical staff have faced a wide variety of challenges, especially during the COVID-19-pandemic. The aim of the VOICE study was to investigate risk and protective factors for workplace-related stress experience and mental health. Method A multicentre, web-based and prospective survey (VOICE study) was initiated in the spring of 2020 by a network of five psychosomatic university clinics (Erlangen, Ulm, Bonn, Cologne and Dresden). More than 25,000 respondents took part in the study at five measurement points. Results Of 3678 employees examined in a hospital setting during the first wave of the pandemic, 17.4% and 17.8% of physicians, 21.6% and 19.0% of nurses and 23.0% and 20.1% of medical-technical assistants (MTA) were affected by symptoms of depression and anxiety, respectively, to a clinically relevant extent. The most important risk factors for depressive and anxiety symptoms were insufficient relaxation during leisure time, increased alcohol consumption, lower trust in colleagues in difficult work situations and increased fear of becoming ill with COVID-19. Predictors for increased post-traumatic symptoms were increased generalized anxiety and depression as well as increased fear of infecting family members. Sense of coherence, social support, optimism and reward level acted as protective factors. Discussion The psychological effects of workplace-related stress during the pandemic were found to be significant. Therefore, regular mental health screening and prevention programmes for healthcare workers are indicated.Open Access funding enabled and organized by Projekt DEAL.Universitätsklinikum Erlangen (8546
Fast and Long‐Term Super‐Resolution Imaging of Endoplasmic Reticulum Nano‐structural Dynamics in Living Cells Using a Neural Network
Get PDFStimulated emission depletion (STED) microscopy is a super‐resolution technique that surpasses the diffraction limit and has contributed to the study of dynamic processes in living cells. However, high laser intensities induce fluorophore photobleaching and sample phototoxicity, limiting the number of fluorescence images obtainable from a living cell. Herein, these challenges are addressed by using ultra‐low irradiation intensities and a neural network for image restoration, enabling extensive imaging of single living cells. The endoplasmic reticulum (ER) is chosen as the target structure due to its dynamic nature over short and long timescales. The reduced irradiation intensity combined with denoising permits continuous ER dynamics observation in living cells for up to 7 h with a temporal resolution of seconds. This allows for quantitative analysis of ER structural features over short (seconds) and long (hours) timescales within the same cell, and enabled fast 3D live‐cell STED microscopy. Overall, the combination of ultralow irradiation with image restoration enables comprehensive analysis of organelle dynamics over extended periods in living cells.Photobleaching and phototoxicity limit the observation time of living cells with super‐resolution fluorescence microscopy. Herein, the authors use low‐illumination microscopy and neural network assisted denoising to achieve fast and long‐term stimulated emission depletion microscopy in living cells. Imaging of the endoplasmic reticulum in live cells at sub‐100 nm spatial resolution and and ≈4 s time resolution over 7 h is demonstrated. image © 2024 WILEY‐VCH GmbHDeutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/50110000165