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Abstract The negatively charged silicon vacancy center ( $${{\rm{V}}}_{{\rm{Si}}}^{-}$$ V Si − ) in silicon carbide (SiC) is an emerging color center for quantum technology covering quantum sensing, communication, and computing. Yet, limited information currently available on the internal spin-optical dynamics of these color centers prevents us from achieving the optimal operation conditions and reaching the maximum performance especially when integrated within quantum photonics. Here, we establish all the relevant intrinsic spin dynamics of the $${{\rm{V}}}_{{\rm{Si}}}^{-}$$ V Si − center at cubic lattice site (V2) in 4H-SiC by an in-depth electronic fine structure modeling including the intersystem-crossing and deshelving mechanisms. With carefully designed spin-dependent measurements, we obtain all the previously unknown spin-selective radiative and non-radiative decay rates. To showcase the relevance of our work for integrated quantum photonics, we use the obtained rates to propose a realistic implementation of time-bin entangled multi-photon GHZ and cluster state generation. We find that up to three-photon GHZ or cluster states are readily within reach using the existing nanophotonic cavity technology.

Abstract Colour centres in silicon carbide emerge as a promising semiconductor quantum technology platform with excellent spin-optical coherences. However, recent efforts towards maximising the photonic efficiency via integration into nanophotonic structures proved to be challenging due to reduced spectral stabilities. Here, we provide a large-scale systematic investigation on silicon vacancy centres in thin silicon carbide membranes with thicknesses down to 0.25 μm. Our membrane fabrication process involves a combination of chemical mechanical polishing, reactive ion etching, and subsequent annealing. This leads to highly reproducible membranes with roughness values of 3–4 Å, as well as negligible surface fluorescence. We find that silicon vacancy centres show close-to lifetime limited optical linewidths with almost no signs of spectral wandering down to membrane thicknesses of ~0.7 μm. For silicon vacancy centres in thinner membranes down to 0.25 μm, we observe spectral wandering, however, optical linewidths remain below 200 MHz, which is compatible with spin-selective excitation schemes. Our work clearly shows that silicon vacancy centres can be integrated into sub-micron silicon carbide membranes, which opens the avenue towards obtaining the necessary improvements in photon extraction efficiency based on nanophotonic structuring.

Abstract Background Currently, a conclusive experience on the uniform implementation and benefits of day hospice structures and interventions is lacking in Germany. The following questions should be clarified: (1) Which structural conditions and interventional measures should be established in day hospices from the point of view of patients, relatives, and specialist staff?; (2) Are the planned structures or interventions feasible and implementable under real conditions and accepted by patients, relatives, and staff?; (3) How can a final implementation and intervention catalog for day hospices be designed?; (4) Is this final catalog of services feasible, reasonable, economical, and effective under everyday conditions in day hospices? Methods We planned to perform a multistage investigation, guided by the Medical Research Council Framework for the development and evaluation of complex interventions. In Stage 1, an initial theoretical construct on structures and interventions will be established through an extensive literature and guideline review on day hospices and through qualitative interviews. In a nominal group process, we will create a catalog of offers. In Stage 2, feasibility testing is conducted in a single-day hospice under real-life conditions using quantitative quality indicators and qualitative interviews. Structures and interventions can be adapted here if necessary. In a second nominal group process, a final structure and offer catalog is created, which is then implemented in Stage 3 in the day hospice under investigation and evaluated under real daily conditions through a process and effectiveness test. For this purpose, qualitative and quantitative quality indicators will be used and a comparative cohort of patients who are not cared for in the day hospice – but in the same network structure (oncology–palliative care network Lower Bavaria) – is examined. Discussion Finally, the initial statements on the reasonable and realizable structures or interventions in day hospices and their benefits in daily real-life conditions as well as possible optimization processes shall be made. Trial registration The study was retrospectively registered in the German Clinical Trials Register (DRKS-ID DRKS00031613, registration date April 04, 2023) and the display portal of the Center for Clinical Trials of the University Hospital Regensburg (Z-2022-1734-6, registration date July 01, 2023).

Abstract The recent outbreak of the COVID-19 pandemic caused by severe acute respiratory syndrome-Coronavirus-2 (SARS-CoV-2) has shown the necessity for fast and broad drug discovery methods to enable us to react quickly to novel and highly infectious diseases. A well-known SARS-CoV-2 target is the viral main 3-chymotrypsin-like cysteine protease (Mpro), known to control coronavirus replication, which is essential for the viral life cycle. Here, we applied an interaction-based drug repositioning algorithm on all protein-compound complexes available in the protein database (PDB) to identify Mpro inhibitors and potential novel compound scaffolds against SARS-CoV-2. The screen revealed a heterogeneous set of 692 potential Mpro inhibitors containing known ones such as Dasatinib, Amodiaquine, and Flavin mononucleotide, as well as so far untested chemical scaffolds. In a follow-up evaluation, we used publicly available data published almost two years after the screen to validate our results. In total, we are able to validate 17% of the top 100 predictions with publicly available data and can furthermore show that predicted compounds do cover scaffolds that are yet not associated with Mpro. Finally, we detected a potentially important binding pattern consisting of 3 hydrogen bonds with hydrogen donors of an oxyanion hole within the active side of Mpro. Overall, these results give hope that we will be better prepared for future pandemics and that drug development will become more efficient in the upcoming years.

Background: More than 80% of the residents in German hospices suffer from tumor disease. But the administration of supportive-oncological therapies in hospices for symptom control is controversially discussed. Objectives: This study aims to investigate the care situation of tumor patients in German hospices with regard to medical care and the use of supportive-oncological therapies. Methods: In February 2019, all hospices in Germany were offered the opportunity to participate in an anonymous online survey on medical and drug care for their tumor patients. The survey was conducted using the online platform SoSci Survey and ended in April 2019. The analysis was descriptive. Results: Of 202 hospices, 112 responded to the questionnaire. The hospices were distributed nationwide. Most have 8 to 10 places. More than 80% of hospice residents are tumor patients, and the length of stay is usually three to four weeks. Medical care is primarily provided by primary care physicians. While specialized outpatient palliative care is increasingly involved in care, hematologists/oncologists are rarely represented. Supportive-oncological therapies are rarely prescribed, whereas medication for other chronic conditions is often continued. The percentage of supportive-oncological therapies prescribed is higher in hospices with oncology co-care. Conclusions: Although most hospice residents suffer from malignant disease, co-care by a hematologist/oncologist is rare. Supportive-oncology therapies, particularly for symptom relief, may therefore be rarely used. However, since a small select group of hospice residents may benefit from these therapies, further investigation in this direction should be undertaken.

Cyber-attacks have a tremendous impact on worldwide economic performance. Hence, it is vitally important to implement effective risk management for different cyber-attacks, which calls for profound attacker models. However, cyber risk modelling based on attacker models seems to be restricted to overly simplified models. This hinders the understanding of cyber risks and represents a heavy burden for efficient cyber risk management. This work aims to forward scientific research in this field by employing a multi-method approach based on a quantitative content analysis of scientific literature and a natural experiment. Our work gives evidence for the oversimplified modelling of attacker motivational patterns. The quantitative content analysis gives evidence for a broad and established misunderstanding of attackers as being illicitly malicious. The results of the natural experiment substantiate the findings of the content analysis. We thereby contribute to the improvement of attacker modelling, which can be considered a necessary prerequisite for effective cyber risk management.

IntroductionEarly tumor shrinkage (ETS), depth of response (DpR), and time to DpR represent exploratory endpoints that may serve as early efficacy parameters and predictors of long-term outcome in metastatic colorectal cancer (mCRC). We analyzed these endpoints in mCRC patients treated with first-line bevacizumab-based sequential (initial fluoropyrimidines) versus combination (initial fluoropyrimidines plus irinotecan) chemotherapy within the phase 3 XELAVIRI trial.MethodsDpR (change from baseline to smallest tumor diameter), ETS (≥20% reduction in tumor diameter at first reassessment), and time to DpR (study randomization to DpR image) were analyzed. We evaluated progression-free survival and overall survival with ETS as stratification parameter according to treatment arm, molecular subgroup, and sex.ResultsIn 370 patients analyzed, a higher rate of ETS (60.9% vs. 43.5%; p = 0.001) and significantly greater DpR (-40.0% vs. -24.7%; p < 0.001) were observed in the initial combination therapy arm. The improvement was pronounced in RAS/BRAF wild-type tumors. ETS correlated with improved survival irrespective of treatment arm (PFS: p < 0.001; OS: p = 0.012) and molecular subgroup (PFS: p < 0.001; OS: p < 0.001). Male patients in contrast to female patients with ETS had survival benefit (PFS: p < 0.001, HR 0.532; OS: p < 0.001, HR 0.574 vs. PFS: p = 0.107; OS: p = 0.965).ConclusionsInitial irinotecan-based combination therapy with bevacizumab improved ETS and DpR in mCRC patients with a particularly high irinotecan sensitivity of RAS/BRAF wild-type tumors. ETS seems to be a suitable prognostic marker for fluoropyrimidine- and bevacizumab-based combinations in mCRC. This finding was rather driven by male patients, potentially indicating that ETS might be less predictive of long-term outcome in an elderly, female population.

Abstract Background There is controversy regarding the practical implementation of symptom-focused oncological cancer therapies to hospice residents. In this study, we aim to analyse the use and indication of supportive-oncological cancer therapies in hospices. Methods We conducted a retrospective survey of all residents of two hospice centres in the government district of Lower Bavaria, Germany. Hospice 1 (H1) was a member of an oncological–palliative medical network, and hospice 2 (H2) was independently organized. The evaluation period was the first 40 months after the opening of the respective hospice care centre. Demographical and epidemiological data as well as indications and type of supportive-oncological cancer therapies were recorded. A descriptive analysis and statistical tests were performed. Results Of the 706 residents, 645 had an underlying malignant disease. The average age was 72 years and the mean residence time was 28 days. The most frequent cancer types were gastrointestinal cancers, gynaecological cancers and bronchial carcinomas. Overall 39 residents (33 in H1 and 6 in H2, p

Defects in silicon carbide can act as single photon sources that also have the benefit of a host material that is already used in electronic devices. Here the authors demonstrate that they can control the distinguishability of the emitted photons by changing the defect spin state.

IntroductionThe Covid-19 pandemic has caused great personal stress for medical staff. To ensure adequate outpatient care for cancer patients, extensive safety and hygiene measures must be taken. This interview-based study examines the effects-both personal and professional-of the pandemic on the work routine of outpatient hematology/oncology nurses and medical assistants.Patients, materials and methodsHalf a year after the outbreak of Covid-19 and the introduction of infection control regulations in three outpatient hematological/oncological centers, the affected medical staff (n = 15) were surveyed about the consequences for patient care and clinical work using audio-recorded telephone interviews. The interviews were transcribed and analyzed using a qualitative content analysis.ResultsThe Covid-19 pandemic has complicated the medical care of cancer patients, but only a slight deterioration of medical and psycho-oncological care was observed. The level of stress experienced by medical staff is moderate, with hygiene and safety measures at the workplace helping to reduce stress.ConclusionFrom the point of view of medical staff, the Covid-19 pandemic has had a moderate impact on the outpatient care of cancer patients. Safety measures against Covid-19 are decisive for ensuring the continuation of therapy and for motivating employees.

Point defects in solids have potential applications in quantum technologies, but the mechanisms underlying different defects’ performance are not fully established. Nagy et al. show how the wavefunction symmetry of silicon vacancies in SiC leads to promising optical and spin coherence properties.

Abstract Background Machine learning strategies are prominent tools for data analysis. Especially in life sciences, they have become increasingly important to handle the growing datasets collected by the scientific community. Meanwhile, algorithms improve in performance, but also gain complexity, and tend to neglect interpretability and comprehensiveness of the resulting models. Results Generalized Matrix Learning Vector Quantization (GMLVQ) is a supervised, prototype-based machine learning method and provides comprehensive visualization capabilities not present in other classifiers which allow for a fine-grained interpretation of the data. In contrast to commonly used machine learning strategies, GMLVQ is well-suited for imbalanced classification problems which are frequent in life sciences. We present a Weka plug-in implementing GMLVQ. The feasibility of GMLVQ is demonstrated on a dataset of Early Folding Residues (EFR) that have been shown to initiate and guide the protein folding process. Using 27 features, an area under the receiver operating characteristic of 76.6% was achieved which is comparable to other state-of-the-art classifiers. The obtained model is accessible at https://biosciences.hs-mittweida.de/efpred/. Conclusions The application on EFR prediction demonstrates how an easy interpretation of classification models can promote the comprehension of biological mechanisms. The results shed light on the special features of EFR which were reported as most influential for the classification: EFR are embedded in ordered secondary structure elements and they participate in networks of hydrophobic residues. Visualization capabilities of GMLVQ are presented as we demonstrate how to interpret the results.

The ability to perform high-precision optical measurements is paramount in science and engineering. Laser interferometry enables interaction-free sensing with a precision ultimately limited by shot noise. Quantum optical sensors can surpass this limit but single- or multiphoton schemes are challenged by low experimental sampling rates, while squeezed-light approaches require complex optical setups and sophisticated time gating. Here, we introduce a simple method that infers optical phase shifts through standard intensity measurements while still maintaining the quantum advantage in the measurement precision. Capitalizing on the robustness and high sampling rates of our device, we implement a quantum optical microphone in the audio band. Its performance is benchmarked against a classical laser microphone in a standardized medically approved speech-recognition test on 45 subjects. We find that quantum-recorded words improve the speech-recognition threshold by −0.57dB_{SPL}, thus making the quantum advantage audible. Not only do these results open the door toward applications in quantum nonlinear interferometry but they also show that quantum phenomena can be experienced by humans.

The current study explores implications of Situational Action Theory suggesting that the effect of crime-prone peer associates on delinquency is contingent on the combination of unstructured socializing and personal morals. I analyse this three-way interaction with data from a German adolescent sample, using predictions and (average) marginal effects that were calculated from a multilevel Bayesian negative binomial regression. In line with the implications of Situational Action Theory, the results indicate that criminogenic peer influence depends on unstructured socializing and personal morals. Peer effects on criminal behaviour were marginal among individuals who held strong personal morals against delinquency and among individuals who spent relatively little time in unstructured socializing. Peer effects were greatest among individuals who held weaker morals against delinquency and spent a relatively large amount of time in unstructured socializing. The results underline the importance of studying the contingencies of criminogenic peer effects on personal and environmental factors.

Introduction Five months after COVID-19 first occurred and protective regulations were introduced, patients at three outpatient hematological/oncological centers in Bavaria who had received antiproliferative tumor therapy (n = 30) were questioned about the pandemic’s impact. Patients, materials and methods In recorded semi-structured telephone interviews, the patients answered questions about their quality of life, treatment procedures, their relationship with medical care staff and modern communication technologies. Each interview consisted of 28 questions. The average length of an interview was 30 minutes. The interviews were transcribed and analyzed by means of a qualitative content analysis according to Mayring. Results The COVID-19 pandemic adds to the burden of patients by decreasing their social contacts. They perceived the new isolation and protective measures in outpatient clinics as mostly positive and said its impact had been only slightly adverse. With the implemented safety measures, they feel adequately protected and looked after and want their antiproliferative therapy to be performed as scheduled. Talking to medical staff provides additional reassurance. Conclusion Although the COVID-19 pandemic has exacerbated the social isolation of tumor patients, it has had only a minor effect on tumor therapy in the surveyed patient population. The benefits of modern communication options to tumor patients remains uncertain and should be investigated further in future studies.

In der Fahrzeugindustrie halten aktuell eine Reihe von Neuerungen Einzug. So sorgen neben dem Umstieg auf E‑Mobilität hochtechnologische Assistenzsysteme in Fahrzeugen für einschneidende Veränderungen. Eine weitere mit diesen neuen Systemen einhergehende Neuerung ist, dass Autos nun wie Smartphones mit regelmäßigen Updates versorgt werden. Der Hersteller Tesla behauptet sogar, seine Autos in Zukunft per Softwareupdate zum vollautonomen Fahrzeug upgraden zu können. Diese Entwicklung kann zu einer nicht nachhaltigen und risikoreichen Entwicklung der IT‑Security und der Umweltbilanz des Fahrzeugsektors führen.

The origin of the machinery that realizes protein biosynthesis in all organisms is still unclear. One key component of this machinery are aminoacyl tRNA synthetases (aaRS), which ligate tRNAs to amino acids while consuming ATP. Sequence analyses revealed that these enzymes can be divided into two complementary classes. Both classes differ significantly on a sequence and structural level, feature different reaction mechanisms, and occur in diverse oligomerization states. The one unifying aspect of both classes is their function of binding ATP. We identified Backbone Brackets and Arginine Tweezers as most compact ATP binding motifs characteristic for each Class. Geometric analysis shows a structural rearrangement of the Backbone Brackets upon ATP binding, indicating a general mechanism of all Class I structures. Regarding the origin of aaRS, the Rodin-Ohno hypothesis states that the peculiar nature of the two aaRS classes is the result of their primordial forms, called Protozymes, being encoded on opposite strands of the same gene. Backbone Brackets and Arginine Tweezers were traced back to the proposed Protozymes and their more efficient successors, the Urzymes. Both structural motifs can be observed as pairs of residues in contemporary structures and it seems that the time of their addition, indicated by their placement in the ancient aaRS, coincides with the evolutionary trace of Proto- and Urzymes.