Lebenswissenschaften und Ethik
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Choosing wisely in Germany - adapting an international initiative to a national healthcare agenda
(2016)
Overuse and underuse in healthcare is a chronic problem in most healthcare systems. Inspired by the North American Choosing Wisely Initiative, the Association of Scientific Medical Societies in Germany (AWMF), which actually counts 173 member organisations, decided to address the problem. The aim of the German “Gemeinsam klug entscheiden” (deciding together wisely)-initiative is to reduce overuse, underuse and misuse of health interventions in areas where recommendations of clinical practice guidelines (CPG) are not adequately implemented or missing. Starting point are the positive and negative recommendations of the CPGs, which the AWMF-member societies have developed for more than 20 years, following the manual and rules set up by AWMF. To identify and select recommendations methodological criteria have been developed by a working group in a consensus-based process. The development of AWMF-CPGs follows a methodology that aims to ensure the full integration of evidence, an interdisciplinary and interprofessional perspective, the prevention of bias as a consequence of conflicts of interest and full transparency of the development process.
Cybersecurity and Ethics
(2022)
The text aims to demonstrate that establishing cybersecurity is not only a technical challenge, but that legal, economic, or organizational aspects also play at least as important a role. The provision of cybersecurity raises ethical questions, since cybersecurity can affect moral values such as autonomy, freedom, or privacy. If measurements necessary for the provision of cybersecurity shall be accepted, it is essential to find a balance between the different claims of all stakeholders involved. This aim is achieved through a detailed ethical analysis accompanied by an extensive literature study. As the most important result of this analysis, it becomes obvious that cybersecurity is in competition or even conflict with other values and interests, and that establishing cybersecurity always involves a trade-off. Not only can there be no 100 percent cybersecurity for technical reasons, but if other values and interests are to be considered, this inevitably leads to compromises in cybersecurity.
In Germany, midwives are involved in extensive antenatal and postnatal care. As health professionals, they can play a key role in strengthening health literacy (HL) of parents on how to prevent chronic allergic diseases in their children. The objective of this study is to explore midwives’ perspectives regarding HL-sensitive counselling in early childhood allergy prevention (ECAP). Twenty-four qualitative semi-structured interviews were conducted with midwives, and data were analyzed using qualitative content analysis. Only a small number of study participants were aware of HL as a concept. However, most of these use screening and counselling strategies which consider individual information needs and which support parental HL. HL sensitivity in counselling is largely based on the midwives’ “gut feelings” and counselling experience, rather than on formal education. The midwives were largely aware of evidence-based ECAP recommendations; however, allergy prevention was not seen as a stand-alone topic but as part of their general counselling on infant feeding and hygiene. They found parents to be more open to receiving complex prevention information during antenatal counselling. In order to strengthen midwives’ roles in HL-sensitive ECAP counselling, their formal education should provide them with explicit HL knowledge and counselling skills. ECAP should be an inherent part of antenatal care.
Second cancer risk after radiation of localized prostate cancer with and without flattening filter
(2017)
The Faculty of Electrical Engineering and Information Technology of the OTH Regensburg developed and implemented a compact freshmen seminar for the afternoon of the first day of study. The intention of this seminar is to help the freshmen during their transition between school and study without losing lecture time in the first semester. The concept was tested with one small study group at the beginning of the summer semester 2015. To rate the impact of the seminar and to find aspects for continuous improvement an evaluation method was developed and used. Due to the good student resonance during the first run, this introduction seminar was held again in the winter semester 2015/16. It is planned to integrate this seminar as a regular session for all freshmen of the faculty curriculum and monitor the long-term effects of student motivation and success.
Survey practitioners regularly face the task to draw a sample from a (sub-) population for which no sampling frame exists. Indirect sampling might be a way out in such situations, given that connections exist between the target population and another population for which probability sampling is feasible. While the theory of indirect sampling originated in the context of household panel studies, a wider area of applications emerged during the last decade. We first give a short review of the theory of indirect sampling, show that estimators from indirect samples might have smaller variance than the corresponding direct estimators (contrary to some claims in the literature), summarize recent applications and discuss some issues that are relevant for applying indirect sampling in practice. We also present some theory for unbiased estimation after an additional subsampling stage that was necessary for sampling kindergarten children in the German National Educational Panel Study (NEPS).
The University of Shanghai for Science and Technology (USST), the Coburg University of Applied Sciences and Arts (CUASA) and the OTH Regensburg, University of Applied Sciences (OTHR) established an English taught international cooperative bachelor program in the area of Engineering Physics/Optoelectronics. Students from China study their first four semesters at USST. They continue their studies in Germany for the last three semesters, including an internship and a bachelor thesis, graduating with a Chinese and a German bachelor degree. Students from Germany study their third and fourth semester at USST to gain international experience. While the first cohort of Chinese students is currently in Germany, the second cohort of German students is in Shanghai. Up to now the feedback regarding this study program is completely positive, thus it is planned to develop it further.
This paper discusses modeling and nonlinear control of a joint antagonistically actuated by two pneumatic, artificial muscles. A single model of the whole system is obtained by a combined physical and phenomenological modeling approach. The combined model for the joint, the muscles and the proportional valves results in a nonlinear, affine-in-control system description. The model is used to derive control laws for an input/output linearization approach to linearize the plant. Modeling and parametrization errors are covered via an outer control loop consisting of a state-feedback which is extended by an additional feedback of error integral. Extensive experimental results show the quality of the model and the performance of the respective control laws.
Objectives
Germany has one of the highest numbers of coronary angiography worldwide. Nevertheless, we find a great variation between German regions for both, diagnostic coronary angiographies and percutaneous coronary interventions (PCI). We assume that this variation is not only due to variation in morbidity but also reflects factors such as guideline adherence, physician-patient communication and access to care.
In this mixed method project, we aim to first describe the variation of coronary angiographies and PCIs in different German regions. Secondly, we explore current practices and motives for (non-)adherences to guidelines in the diagnostic process of patients with suspected CHD. Based on these results, we consequently plan to develop a complex intervention (treatment pathway) to improve guideline adherence and thus appropriateness of coronary angiography.
Method
The projects will be organized according to the recommendation of the Medical Research Council for the development and evaluation of complex interventions. The first study will use descriptive methods based on routine data of three German Health Care Insurances and registry data to describe status quo and associated factors of coronary angiography. The second study will use qualitative methods to understand barriers and facilitators of guideline adherence and medical decision making. Furthermore, we will discuss variations in care and thereby identify implementation targets for the planned treatment pathway. Based on this information, we will develop local treatment pathways in four selected regions. Relevant peers will develop the local pathway in group discussions. Using this bottom-up approach, we directly address implementation challenges.
Motivation Centered Learning
(2018)
This Research Work in Progress Paper evaluates students’ motivation sources and shows the high impact that work of professors has on students’ motivation. Common goal of most professors is to help students acquiring knowledge and competencies that are relevant for their further life. From the beginning of Universities’ history, lectures are usually chosen to reach this goal but it is seen in recent years that they are in many cases not the optimal choice. In the last years, many efforts were made to increase students knowledge gain. From learning and motivation psychology research, many details are known how humans remember and transfer knowledge. These research results are used to create new lecture formats to activate students. Research based learning, project based lab courses, problem based learning, feedback systems, flipped classroom, blended learning and gamification in lectures are only some examples for new formats. Common goal of all these new types of learning formats is to increasing students’ motivation and to enhance learning success. In this paper, evaluations using a questionnaire with open questions were done among first year students, bachelor students before graduation and alumni, about their sources of motivation and demotivation. Interesting curricula and lectures with application related topics and possibilities for own work are the main sources of motivation. Enthusiastic professors with high competences and good lecture didactics also contribute to students’ motivation. On the other side, demotivated professors with boring lectures play a much higher role for demotivating students. Therefore, it is necessary to integrate aspects of student motivation into curriculum and lecture design and professors should become aware that they are important role-models for motivating or demotivating students.
Gemeinsam Klug Entscheiden – Initiative der AWMF und ihrer
Fachgesellschaften – ein Werkstattberich
(2017)
Gemeinsam Klug Entscheiden ist eine Initiative der AWMF und ihrer
Fachgesellschaften, mit dem Ziel, Empfehlungen zu Versorgungsaspek-
ten in die Versorgung zu bringen, für die ein großes Verbesserungspoten-
tial besteht. Der Impuls dafür wurde durch die TOP-5-Listen der Choosing
Wisely Kampagne gegeben. Ziel des Posters ist es das Vorgehen und die
Methodik für eine evidenzbasierte Entwicklung bekannt zu machen und
zu diskutieren im Hinblick auf Machbarkeit und Verbesserungspotential.
Reduction of variable-truncation artifacts from beam occlusion during in situ x-ray tomography
(2017)
Many in situ x-ray tomography studies require experimental rigs which may partially occlude the beam and cause parts of the projection data to be missing. In a study of fluid flow in porous chalk using a percolation cell with four metal bars drastic streak artifacts arise in the filtered backprojection (FBP) reconstruction at certain orientations. Projections with non-trivial variable truncation caused by the metal bars are the source of these variable-truncation artifacts. To understand the artifacts a mathematical model of variable-truncation data as a function of metal bar radius and distance to sample is derived and verified numerically and with experimental data. The model accurately describes the arising variable-truncation artifacts across simulated variations of the experimental setup. Three variable-truncation artifact-reduction methods are proposed, all aimed at addressing sinogram discontinuities that are shown to be the source of the streaks. The 'reduction to limited angle' (RLA) method simply keeps only non-truncated projections; the 'detector-directed smoothing' (DDS) method smooths the discontinuities; while the 'reflexive boundary condition' (RBC) method enforces a zero derivative at the discontinuities. Experimental results using both simulated and real data show that the proposed methods effectively reduce variable- truncation artifacts. The RBC method is found to provide the best artifact reduction and preservation of image features using both visual and quantitative assessment. The analysis and artifact-reduction methods are designed in context of FBP reconstruction motivated by computational efficiency practical for large, real synchrotron data. While a specific variable- truncation case is considered, the proposed methods can be applied to general data cut-offs arising in different in situ x-ray tomography experiments.
The main focus of the paper is on the description of the development and current state of research and implementation of patient-centered care (PCC) and shared decision making (SDM) after fifteen years of substantial advances in health policy and health services research.
What is the current state of SDM in health policy?
The "Patients' Rights Act" from 2013 standardizes all rights and responsibilities within the framework of medical treatment for German citizens and legal residents. This comprises the right to informed decisions, comprehensive and comprehensible information for patients, and decisions based on a clinician-patient-partnership.
What is the current state of SDM interventions and patient decision support tools?
SDM training programs for healthcare professionals have been developed. Their implementation in medical schools has been successful. Several decision support tools - primarily with support from health insurance funds and other public agencies - are to be implemented in routine care, specifically for national cancer screening programs.
What is the current state of research and routine implementation?
The German government and other public institutions are constantly funding research programs in which patient-centered care and shared decision-making are important topics. The development and implementation of decision tools for patients and professionals as well as the implementation of CME trainings for healthcare professionals require future efforts.
What does the future look like?
With the support of health policy and scientific evidence, transfer of PCC and SDM to practice is regarded as meaningful. Research can help to assess barriers, facilitators, and needs, and subsequently to develop and evaluate corresponding strategies to successfully implement PCC and SDM in routine care, which remains challenging.
ARTIFICIAL INTELLIGENCE (AI) – ASSISTED VESSEL AND TISSUE RECOGNITION IN THIRD-SPACE ENDOSCOPY
(2022)
Aims
Third-space endoscopy procedures such as endoscopic submucosal dissection (ESD) and peroral endoscopic myotomy (POEM) are complex interventions with elevated risk of operator-dependent adverse events, such as intra-procedural bleeding and perforation. We aimed to design an artificial intelligence clinical decision support solution (AI-CDSS, “Smart ESD”) for the detection and delineation of vessels, tissue structures, and instruments during third-space endoscopy procedures.
Methods
Twelve full-length third-space endoscopy videos were extracted from the Augsburg University Hospital database. 1686 frames were annotated for the following categories: Submucosal layer, blood vessels, electrosurgical knife and endoscopic instrument. A DeepLabv3+neural network with a 101-layer ResNet backbone was trained and validated internally. Finally, the ability of the AI system to detect visible vessels during ESD and POEM was determined on 24 separate video clips of 7 to 46 seconds duration and showing 33 predefined vessels. These video clips were also assessed by an expert in third-space endoscopy.
Results
Smart ESD showed a vessel detection rate (VDR) of 93.94%, while an average of 1.87 false positive signals were recorded per minute. VDR of the expert endoscopist was 90.1% with no false positive findings. On the internal validation data set using still images, the AI system demonstrated an Intersection over Union (IoU), mean Dice score and pixel accuracy of 63.47%, 76.18% and 86.61%, respectively.
Conclusions
This is the first AI-CDSS aiming to mitigate operator-dependent limitations during third-space endoscopy. Further clinical trials are underway to better understand the role of AI in such procedures.
Aims
Barrett´s esophagus related neoplasia (BERN) is difficult to detect and characterize during endoscopy, even for expert endoscopists. We aimed to assess the add-on effect of an Artificial Intelligence (AI) algorithm (Barrett-Ampel) as a decision support system (DSS) for non-expert endoscopists in the evaluation of Barrett’s esophagus (BE) and BERN.
Methods
Twelve videos with multimodal imaging white light (WL), narrow-band imaging (NBI), texture and color enhanced imaging (TXI) of histologically confirmed BE and BERN were assessed by expert and non-expert endoscopists. For each video, endoscopists were asked to identify the area of BERN and decide on the biopsy spot. Videos were assessed by the AI algorithm and regions of BERN were highlighted in real-time by a transparent overlay. Finally, endoscopists were shown the AI videos and asked to either confirm or change their initial decision based on the AI support.
Results
Barrett-Ampel correctly identified all areas of BERN, irrespective of the imaging modality (WL, NBI, TXI), but misinterpreted two inflammatory lesions (Accuracy=75%). Expert endoscopists had a similar performance (Accuracy=70,8%), while non-experts had an accuracy of 58.3%. When AI was implemented as a DSS, non-expert endoscopists improved their diagnostic accuracy to 75%.
Conclusions
AI may have the potential to support non-expert endoscopists in the assessment of videos of BE and BERN. Limitations of this study include the low number of videos used. Randomized clinical trials in a real-life setting should be performed to confirm these results.
On closer examination, the concept of civil society becomes blurred, for instance, on the crucial question of who belongs to civil society. The different answers to this question show how controversial the concept of civil society is, since it cannot be assumed that members of civil society would be morally particularly preferable actors. If, however, the conceptual foundations of and the question of membership in civil society already raise doubts about this concept, the recourse to civil society as a means against fake news and hate speech itself, which is often heard in public debates, becomes doubtful.
Background
The aim of this study was to investigate if the flattening filter free mode (FFF) of a linear accelerator reduces the excess absolute risk (EAR) for second cancer as compared to the flat beam mode (FF) in simultaneous integrated boost (SIB) radiation therapy of right-sided breast cancer.
Patients and methods
Six plans were generated treating the whole breast to 50.4 Gy and a SIB volume to 63 Gy on CT data of 10 patients: intensity-modulated radiation therapy (IMRT), volumetric modulated arc therapy (VMAT), and a tangential arc VMAT (tVMAT), each with flattening filter and without. The EAR was calculated for the contralateral breast and the lungs from dose-volume histograms (DVH) based on the linear-exponential, the plateau, and the full mechanistic dose-response model. Peripheral low-dose measurements were performed to compare the EAR in more distant regions as the thyroids and the uterus.
Results
FFF reduces the EAR significantly in the contralateral and peripheral organs for tVMAT and in the peripheral organs for VMAT. No reduction was found for IMRT. The lowest EAR for the contralateral breast and lung was achieved with tVMAT FFF, reducing the EAR by 25 % and 29 % as compared to tVMAT FF, and by 44 % to 58 % as compared to VMAT and IMRT in both irradiation modes. tVMAT FFF showed also the lowest peripheral dose corresponding to the lowest EAR in the thyroids and the uterus.
Conclusion
The use of FFF mode allows reducing the EAR significantly when tVMAT is used as the treatment technique. When second cancer risk is a major concern, tVMAT FFF is considered the preferred treatment option in SIB irradiation of right-sided breast cancer.
Celiac disease is an autoimmune disorder caused by gluten that results in an inflammatory response of the small intestine.We investigated whether celiac disease can be detected using endoscopic images through a deep learning approach. The results show that additional clinical parameters can improve the classification accuracy. In this work, we distinguished between healthy tissue and Marsh III, according to the Marsh score system. We first trained a baseline network to classify endoscopic images of the small bowel into these two classes and then augmented the approach with a multimodality component that took the antibody status into account.
Vascular malformations (VMs) are a rare condition. They can be categorized into high-flow and low-flow VMs, which is a challenging task for radiologists. In this work, a very heterogeneous set of MRI images with only rough annotations are used for classification with a convolutional neural network. The main focus is to describe the challenging data set and strategies to deal with such data in terms of preprocessing, annotation usage and choice of the network architecture. We achieved a classification result of 89.47 % F1-score with a 3D ResNet 18.
As a result of increasing globalisation, universities are being confronted by the challenge of adapting their teaching standards to meet the demands of a more dynamic labour market. Entrepreneurship education provides an important contribution to improving students ́ entrepreneurial competencies and stimulating innovative work behaviour. Based on the current state of research, as well as on the results of an empirical comparative study at partner institutions of applied sciences, this article describes how the internationalisation of curricula with regards to the academic teaching of entrepreneurship and the promotion of entrepreneurial competence can be structured. An online survey of students carried out within the framework of an EU project, as well as joint class observations, revealed some important differences in study-related matters, which emphasises the need for stronger cooperation in terms of cross-border employability. With regards to the promotion of entrepreneurial thinking and behaviour, it appears appropriate to intensify the use of case-based instructional designs within teaching standards, to extend the supportive offers to students and to enable engagement with entrepreneurship in various courses of studies.
Pediatric patients suffering from ependymoma are usually treated with cranial or craniospinal three-dimensional (3D) conformal radiotherapy (3DCRT). Intensity-modulated techniques spare dose to the surrounding tissue, but the risk for second malignancies may be increased due to the increase in low-dose volume. The aim of this study is to investigate if the flattening filter free (FFF) mode allows reducing the risk for second malignancies compared to the mode with flattening filter (FF) for intensity-modulated techniques and to 3DCRT. A reduction of the risk would be advantageous for treating pediatric ependymoma. 3DCRT was compared to intensity-modulated radiation therapy (IMRT) and volumetric-modulated arc therapy (VMAT) with and without flattening filter. Dose-volume histograms (DVHs) were compared to evaluate the plan quality and used to calculate the excess absolute risk (EAR) to develop second cancer in the brain. Dose verification was performed with a two-dimensional (2D) ionization chamber array and the out-of-field dose was measured with an ionization chamber to determine the EAR in peripheral organs. Delivery times were measured. Both VMAT and IMRT achieved similar plan quality in terms of dose sparing in the OAR and higher PTV coverage as compared to 3DCRT. Peripheral dose in low-dose region, which is proportional to the EAR in organs located in this region, for example, gonads, bladder, or bowel, could be significantly reduced using FFF. The lowest peripheral EAR and lowest delivery times were hereby achieved with VMATFFF . The EAR calculated based on DVH in the brain could not be reduced using FFF mode. VMATFFF improved the target coverage and homogeneity and kept the dose in the OAR similar compared to 3DCRT. In addition, delivery times were significantly reduced using VMATFFF . Therefore, for radiotherapy of ependymoma patients, VMATFFF may be considered advantageous for the combination of Elekta Synergy linac and Oncentra External Beam planning system used in this study.
Against the background of the huge rise in the number of asylum seekers and refugees absorbed into German society over the last couple of years this article examines the innovative Bavarian programme of preparatory classes for asylum seekers between 16 and 21 years of age. The challenges faced by educational and social work professionals working with this target group are documented alongside the particular resources which these highly-motivated young people as a rule bring with them. Specific requirements for psychotherapy professionals are addressed as well as a range of recommendations formulated by the author to enable the longer-term success of this vocational training programme in integrating these young people into the German educational and employment system. It has become apparent that a holistic approach to the lives of the target group by professionals in education, social work and therapy is necessary to enable young asylums seekers to complete vocational training successfully. Transitional management is a key part of the process of setting asylum seekers on the path to an apprenticeship. Coordination with the Labour Office, local authority administration and local decision-makers are further parts of the equation. This must intermesh with civil society engagement to provide the maximum use of resources giving young refugees access to training, the labour market and long term integration into German life.
By many accounts, the Newtonian constant of gravitation G is the fundamental constant that is most difficult to measure accurately. Over the past three decades, more than a dozen precision measurements of this constant have been performed. However, the scatter of the data points is much larger than the uncertainties assigned to each individual measurement, yielding a Birge ratio of about five. Today, G is known with a relative standard uncertainty of 4.7 x 10(-5), which is several orders of magnitudes greater than the relative uncertainties of other fundamental constants. In this article, various methods to measure G are discussed. Alarge array of different instruments ranging from the simple torsion balance to the sophisticated atom interferometer can be used to determine G. Some instruments, such as the torsion balance can be used in several different ways. In this article, the advantages and disadvantages of different instruments as well as different methods are discussed. A narrative arc from the historical beginnings of the different methods to their modern implementation is given. Finally, the article ends with a brief overview of the current state of the art and an outlook.
Purpose
The complexity of the treatment techniques IMRT (Intensity Modulated Radiation Therapy) and VMAT (Volumetric Modulated Arc Therapy) introduced the requirement of an individual plan verification. The latest development is 3D verification which allows evaluation in terms of 3D gamma values but also a judgment based on differences in dose distributions on individual patient CT data and in dose volume histograms. For a verification tool the error detection sensitivity is important. The purpose of this work is to evaluate the accuracy and the sensitivity of the gamma evaluation of the 3D verification software MobiusFx when a systematic error in one parameter is applied. The results are compared to an established 2D-measurement based method.
Methods
11 IMRT and 11 VMAT plans were selected as reference plans. For every reference plan a systematic offset of 1 mm, 2 mm and 3 mm in the same direction was applied to the Multi-Leaf-Collimator (MLC) positions. All plans were irradiated and verified simultaneously with MobiusFx and MatriXX Evolution 2D array measurement. For both verification systems the applied dose distributions were evaluated using the gamma method based on the reference plans. In MobiusFx additionally the MLC position errors were evaluated.
Results
Regarding the gamma evaluation results, MobiusFx and MatriXX Evolution 2D measurements have almost the same sensitivity: The gamma evaluation of both systems detected shifts of 1 mm in VMAT plans and shifts of 2 mm and larger in IMRT plans. The information of the MLC position error provided by MobiusFx allows further to detect errors down to a shift of 1 mm in IMRT plans, giving an advantage over the MatriXX measurement.
Conclusions
MobiusFx shows a high error detection sensitivity, comparable to MatriXX Evolution. Through the gamma calculation and the MLC position error it is possible to detect errors down to a shift in MLC positions of 1 mm. It is recommended to inspect all the above parameters during plan verification.
During recent years, there has been a trend to replace traditional lab courses by project-based learning activities. However, there is currently little scientific evidence for educational improvements through such changes. Some years ago, a lab course on electrical measurements in our bachelor Electrical Engineering and Information Technology was modified from single experiments to projects. This change led to a significant increase in the necessary manpower and lab costs. To justify these higher efforts, it is important to investigate if the learning success increased. We carried out the surveys and collected the statistical data from the students who attended this course. In order to see if the students appreciated this lab course and if there was an objective increase of the students' knowledge, these results were evaluated. Evaluation of the grades in the lecture and lab courses shows that the increase of the students' theoretical and practical knowledge is statistically significant.
Mathematical analysis of the 1D model and reconstruction schemes for magnetic particle imaging
(2018)
Magnetic particle imaging (MPI) is a promising new in vivo medical imaging modality in which distributions of super-paramagnetic nanoparticles are tracked based on their response in an applied magnetic field. In this paper we provide a mathematical analysis of the modeled MPI operator in the univariate situation. We provide a Hilbert space setup, in which the MPI operator is decomposed into simple building blocks and in which these building blocks are analyzed with respect to their mathematical properties. In turn, we obtain an analysis of the MPI forward operator and, in particular, of its ill-posedness properties. We further get that the singular values of the MPI core operator decrease exponentially. We complement our analytic results by some numerical studies which, in particular, suggest a rapid decay of the singular values of the MPI operator.
We propose a new permanent magnet system for Kibble balance experiments, which combines advantages of the magnet designs invented by the National Physical Laboratory (NPL) and by the Bureau International des Poids et Mesures (BIPM). The goal of the proposed magnet system is to minimize the coil-current effect and to optimize the shielding at the same time. In the proposed design, a permanent magnet system with two gaps, each housing a coil, is employed to minimize the coil current effect, by reducing the linear coil-current dependence reported for the single air gap design by at least one order of magnitude. Both air gaps of the magnet are completely surrounded by high-permeability material, and hence the coils are shielded from outside magnetic fields and no magnetic field leaks outside of the magnet system. An example of the new magnet system is given and the analysis shows that the magnetic field in the air gap can be optimized to meet the requirement to be used in Kibble balances.
The implant stability and biomechanical response of periprosthetic bone in acetabulum around total hip joint replacement (THR) devices depend on a host of parameters, including design of articulating materials, gait cycle and subject parameters. In this study, the impact of shell design (conventional, finned, spiked, and combined design) and liner material on the biomechanical response of periprosthetic bone has been analyzed using finite element (FE) method. Two different liner materials: high density polyethylene-20% hydroxyapatite-20% alumina (HDPE-20%HA-20%Al2O3) and highly cross-linked ultrahigh molecular weight polyethylene (HC-UHMWPE) were used. The subject parameters included bone condition and bodyweight. Physiologically relevant load cases of a gait cycle were considered. The deviation of mechanical condition of the periprosthetic bone due to implantation was least for the finned shell design. No significant deviation was observed at the bone region adjacent to the spikes and the fins. This study recommends the use of the finned design, particularly for weaker bone conditions. For stronger bones, the combined design may also be recommended for higher stability. The use of HC-UHMWPE liner was found to be better for convensional shell design. However, similar biomechanical response was captured in our FE analysis for both the liner materials in case of other shell designs. Overall, the study establishes the biomechanical response of periprosthetic bone in the acetabular with preclinically tested liner materials together with new shell design for different subject conditions.
Epigenetic modifiers of the histone deacetylase (HDAC) family contribute to autoimmunity, cancer, HIV infection, inflammation, and neurodegeneration. Hence, histone deacetylase inhibitors (HDACi), which alter protein acetylation, gene expression patterns, and cell fate decisions, represent promising new drugs for the therapy of these diseases. Whereas pan-HDACi inhibit all 11 Zn2+-dependent histone deacetylases (HDACs) and cause a broad spectrum of side effects, specific inhibitors of histone deacetylase 6 (HDAC6i) are supposed to have less side effects. We present the synthesis and biological evaluation of Marbostats, novel HDAC6i that contain the hydroxamic acid moiety linked to tetrahydro-β-carboline derivatives. Our lead compound Marbostat-100 is a more potent and more selective HDAC6i than previously established well-characterized compounds in vitro as well as in cells. Moreover, Marbostat-100 is well tolerated by mice and effective against collagen type II induced arthritis. Thus, Marbostat-100 represents a most selective known HDAC6i and the possibility for clinical evaluation of a HDAC isoform-specific drug.
Over the past decade, veno-venous extracorporeal membrane oxygenation (vvECMO) has been increasingly utilized in respiratory failure in patients. This study presents our institution´s experience focusing on the life span of ECMO systems reflecting the performance of a particular system. A retrospective review of our ECMO database identified 461 adult patients undergoing vvECMO (2010-2017). Patients that required more than one system and survived the first exchange >24 hours (n = 139) were included. Life span until the first exchange and exchange criteria were analyzed for all systems (PLS, Cardiohelp HLS-set, both Maquet Cardiopulmonary, Rastatt, Germany; Deltastream/Hilite7000LT, iLA-activve, Xenios/NovaLung, Heilbronn, Germany; ECC.O5, LivaNova, Mirandola, Italy). At our ECMO center, the frequency of a system exchange was 30%. The median (IQR) life span was 9 (6-12) days. There was no difference regarding the different systems (p = 0.145 and p = 0.108, respectively). However, the Deltastream systems were exchanged more frequently due to elective technical complications (e. g. worsened gas transfer, development of coagulation disorder, increased bleedings complications) compared to the other exchanged systems (p = 0.013). In summary, the used ECMO systems are safe and effective for acute respiratory failure. There is no evidence for the usage of a specific system. Only the increased predictability of an imminent exchange preferred the usage of a Deltastream system. However, the decision to use a particular system should not depend solely on the possible criteria for an exchange.
Natural and technological hazards have a major impact on environmental and human safety. Risk assessment plays an essential role in the risk management of the effects of such hazards. This contribution summarizes first the general formulation of risk depending on two parameters: hazard probability and associated consequences. Problems faced in industrial applications based on the experience of the author are discussed. Risk acceptance criteria for the contributors to risk i.e. human, economic and environment are critically reviewed. Resilience based criteria are also included and conclusions for future developments are provided.
This study examines attitudes toward assisted reproductive technologies (ART) among immigrant women and non-migrants in Germany. The social relevance of ART is increasing in Western countries due to overall low birth rates, a high rate of childlessness, and a gap between the desired and the actual numbers of children. Previous literature has been scarce, however, on attitudes toward ART, and immigrant minorities have rarely been included in studies on ART.
Our working hypotheses are drawn from theoretical considerations on political socialisation and cultural integration. The analysis is based on data collected in a pilot study in 2014 and 2015. The sample includes 960 women aged 18 to 50 living in Germany. About 81 percent of the sample are immigrants who originate from Turkey, Poland, the Balkan countries, or countries of the (Russian) Commonwealth of Independent States (CIS). We study the social norm to use ART to have a child, the personal attitude of whether a woman would use ART herself, and the methods that they would consider for their own use.
Our results show that ART is overall socially acceptable, and the majority of women said that they would use it if necessary. There is significant variation between the origin groups, however. Non-migrants show the lowest acceptance rates and migrants from Poland and Turkey the highest approval. There is also variation in the ART procedures considered for use with the migrants more approving of heterologous methods than non-migrants. The differences between the origin groups diminish only partly when controlling for further explanatory variables, i.e. gender-role attitudes, religiosity, and socio-demographic characteristics of the respondents.
We conclude that attitudes toward ART are shaped less by socio-demographic characteristics, but rather by cultural factors and the socialization in the migrants' countries of origin. The diversity in attitudes toward ART by cultural background should be acknowledged in research and public discourses on ART as well as in regulating policies.
Degradation and release of tannic acid from an injectable tissue regeneration bead matrix in vivo
(2021)
The development of multifunctional biomaterials as both tissue regeneration and drug delivery devices is currently a major focus in biomedical research. Tannic Acid (TA), a naturally occurring plant polyphenol, displays unique medicinal abilities as an antioxidant, an antibiotic, and as an anticancer agent. TA has applications in biomaterials acting as a crosslinker in polymer hydrogels improving thermal stability and mechanical properties. We have developed injectable cell seeded collagen beads crosslinked with TA for breast reconstruction and anticancer activity following lumpectomy. This study determined the longevity of the bead implants by establishing a degradation time line and TA release profile in vivo. Beads crosslinked with 0.1% TA and 1% TA were compared to observe the differences in TA concentration on degradation and release. We found collagen/TA beads degrade at similar rates in vivo, yet are resistant to complete degradation after 16 weeks. TA is released over time in vivo through diffusion and cellular activity. Changes in mechanical properties in collagen/TA beads before implantation to after 8 weeks in vivo also indicate loss of TA over a longer period of time. Elastic moduli decreased uniformly in both 0.1% and 1% TA beads. This study establishes that collagen/TA materials can act as a drug delivery system, rapidly releasing TA within the first week following implantation. However, the beads retain TA long term allowing them to resist degradation and remain in situ acting as a cell scaffold and tissue filler. This confirms its potential use as an anticancer and minimally invasive breast reconstructive device following lumpectomy.
We show that templating a Si surface with a focused beam of Si2+ or Si+ ions can create suitable nucleation sites for the subsequent growth of self-assembled Ge quantum dots by chemical vapor deposition. To determine the mechanism of patterning we use atomic force microscopy to show that, similar to Ga+ patterning, the formation of a surface pit is required to enable control over Ge quantum dot locations. We find that relatively high implantation doses are required to achieve patterning, and these doses lead to amorphization of the substrate. We assess the degree to which the substrate crystallinity can be recovered by subsequent processing. Using in situ transmission electron microscopy heating experiments we find that recrystallization is possible at the growth temperature of the Ge quantum dots, but defects remain that follow the pattern of the initial implantation. We discuss the formation mechanism of the defects and the benefits of using Si ions for patterning both defects and quantum dots on Si substrates.
This paper provides an overview of the state of art of research on social entrepreneurship and the establishment of this topic in the academic world, It uses scientometric methods in measuring the maturity of social entrepreneurship research. The empirical part reveals the exponentially growing number of papers, the institutionalization of social entrepreneurship in seven dimensions the emergence of thematic clusters, and methodological issues. The paper makes concrete suggestions on how to overcome methodological challenges. Furthermore, we provide a ranking of the 22 most cited academic contributions in social entrepreneurship. Surprisingly, almost half of the most cited papers have not been published in journals but in books, raising doubts about the current (over-)rating of journal publications.
Aims
Congenital breast asymmetry represents a particular challenge to the classic techniques of plastic surgery given the young age of patients at presentation. This study reviews and compares the long-term results of traditional breast augmentation using silicone implants and the more innovative technique of lipografting.
Methods
To achieve this, we not only captured subjective parameters such as satisfaction with outcome and symmetry, but also objective parameters including breast vol-ume and anthropometric measurements. The objective examination was performed manually and by using the Vectra H2 photogrammetry scanning system.
Results
Differences between patients undergoing either implant augmentation or lipograft were revealed not to be significant with respect to patient satisfaction with surgical outcome (p= 0.55) and symmetry (p= 0.69). Furthermore, a breast symmetry of 93 % was reported in both groups. Likewise, no statistically significant volume difference between the left and right breasts was observed in both groups (p\0.41). However, lipograft patients needed on average 2.9 procedures to achieve the desired result, compared with 1.3 for implant augmentation. In contrast, patients treated with implant augmentation may require anumber of implant changes during their lifetime.
Conclusion
Both methods may be considered for patients presenting with congenital breast asymmetry.
We present the Regensburg Breast Shape Model (RBSM)—a 3D statistical shape model of the female breast built from 110 breast scans acquired in a standing position, and the first publicly available. Together with the model, a fully automated, pairwise surface registration pipeline used to establish dense correspondence among 3D breast scans is introduced. Our method is computationally efficient and requires only four landmarks to guide the registration process. A major challenge when modeling female breasts from surface-only 3D breast scans is the non-separability of breast and thorax. In order to weaken the strong coupling between breast and surrounding areas, we propose to minimize the variance outside the breast region as much as possible. To achieve this goal, a novel concept called breast probability masks (BPMs) is introduced. A BPM assigns probabilities to each point of a 3D breast scan, telling how likely it is that a particular point belongs to the breast area. During registration, we use BPMs to align the template to the target as accurately as possible inside the breast region and only roughly outside. This simple yet effective strategy significantly reduces the unwanted variance outside the breast region, leading to better statistical shape models in which breast shapes are quite well decoupled from the thorax. The RBSM is thus able to produce a variety of different breast shapes as independently as possible from the shape of the thorax. Our systematic experimental evaluation reveals a generalization ability of 0.17 mm and a specificity of 2.8 mm. To underline the expressiveness of the proposed model, we finally demonstrate in two showcase applications how the RBSM can be used for surgical outcome simulation and the prediction of a missing breast from the remaining one. Our model is available at https://www.rbsm.re-mic.de/.
In recent years, our society faced a massive interconnection of computer-based everyday objects, which opens these items for cyber-attacks. Dependent on the physical capabilities, successful attacks can vary from data exposure or a loss of functionality to a threat to life and limb. Connected- and autonomous vehicles are extremely safety-critical systems with a huge damage potential. This global trend, together with existing and upcoming regulations (ISO 270xx, ISO 21434, UNECE WP.29, UNECE R155), and the lack of qualified professionals create a tension field for the entire automotive industry.
Hence, new education concepts for engineers of safety-critical and connected systems are necessary to secure our daily and future systems against cyber-attacks and raise awareness and knowledge of the topic of IT-Security. Existing automotive security education systems have one common problem: All systems are hardware-based and therefore have very steep learning curves for beginners. Hardware-based systems, in general, are expensive in their initial costs, require regular maintenance, and add diverse operational difficulties independent of the aspired education goal. Additionally, the global pandemic increased the necessity of virtual education concepts for security training in cyber-physical systems.
Therefore, we present a novel concept for the education of cyber-security professionals for automotive systems based on discovery and problem-based learning in a virtual learning environment (VLE). Our concept contains individual exercises focusing on the topics of vulnerabilities and attacks in automotive networks and systems. Each exercise relates those topics to the corresponding security goals and countermeasures for mitigation. The learners work collaboratively in a self-contained manner within the VLE to acquire the necessary information to answer questions or find a solution to the given problem. To consider the heterogeneous background (e.g. knowledge, experience, preconceptions) of the learners, the topics can be presented in different difficulties, enabling an adaptable learning environment and different learning trajectories within the exercises.
The concept is based on a VLE, consisting of automotive networks and components, which simulate the behavior of a vehicle. This environment provides a hands-on, "real-life" scenario, which allows discovery and problem-based learning in a realistic, but cheap and scalable education environment. Furthermore, virtualization removes common difficulties, always present in training on real hardware. This aims to decrease complexity, prevent learning obstacles related to hardware handling, and enables a location-independent learning environment.
The target group of our education concept is Bachelor and Master students of computer science, engineering (e.g. electrical engineering, mechatronics), or similar studies, and (experienced) engineers from the industry.
In summary, our publication contains two contributions. We present an adaptable virtual learning environment for automotive security education, combined with an educational concept based on discovery and problem-based learning techniques. The goals of our concept are the education of cyber-security professionals for safety-critical, connected automotive systems and the support of life-long learning reaching from academic education to training in the industry.
Blood flow in channels of varying diameters <500μm exhibits strong non-linear effects. Multiphase finite volume approaches are feasible, but still computationally costly. Here, the feasibility of applying convolutional neural networks for blood flow prediction in artificial lungs is investigated. Training targets are precomputed using an Eulerian two-phase approach. To match with experimental data, the interphase drag and lift, as well as intraphase shear-thinning are adapted. A recursively branching regression network and convolution/deconvolution networks with plain skip connections and densely connected skips are investigated. A priori knowledge is incorporated in the loss functional to prevent the network from learning non-physical solutions. Inference from neural networks is approximately six orders of magnitude faster than the classical finite volume approach. Even if resulting in comparably coarse flow fields, the neural network predictions can be used as close to convergence initial solutions greatly accelerating classical flow computations.
At risk of reproductive disadvantage? Exploring fertility awareness among migrant women in Germany
(2022)
This study examined awareness about fertility among immigrant women and non-migrants in Germany. The social relevance of infertility and fertility treatment is increasing in Western countries due to continually low overall birth rates, a high rate of childlessness, and a gap between the desired and actual numbers of children. While there is growing interest in infertility and reproductive medicine in general, previous studies have rarely included immigrant or ethnic minorities in Europe. This study investigated whether knowledge on the age-related fertility decline (ARFD) varies between migrant groups and the majority group, and the role of education. Working hypotheses were drawn from theoretical considerations on frameworks of migrant assimilation. The analysis was based on data collected in a social science pilot study on reproductive medicine, representative of the general population (‘NeWiRe’ 2014–2015). The sample included 962 women aged 18–50 years living in Germany. Approximately 81% of the sample were immigrants who originated from Turkey, Poland, the Balkan countries or countries of the (post-Soviet) Commonwealth of Independent States. While rather poor overall, knowledge on ARFD was found to be significantly lower in the migrant groups compared with the majority group. This minority-group disadvantage cannot be explained by sociodemographic or cultural variables. Future research should include minority groups in empirical studies on awareness about fertility in order to better understand the causes of this disadvantage, and the potential reproductive needs of migrants.
An amateur radio lecture was developed and is conducted within the general education program of the Ostbayerische Technische Hochschule Regensburg. This course enables the students to participate in a variety of activities within the university. Different learning formats for communication engineering are carried out in combination with an amateur radio station of the university. Additionally, some of the projects serve as anchor points for increased visibility of the university in local society, e.g. by carrying out public events in connection with the local amateur radio community. It is seen that this course together with the amateur radio station have several positive effects for technical education and university visibility.
This paper presents experiences with a digitalized concept for teaching control theory as minor subject with an integrated approach for lectures, exercises and practical sessions in the department of electrical engineering at the OTH Regensburg. The concept uses activating methods like blended learning and possibilities of digitalization of teaching implementing Just in Time Teaching and Peer Instruction. The basis for the new concept is the idea of constructive alignment. Furthermore this paper presents feedback from the students along with an accompanying scientific research over several semesters focusing on the development over past semesters.
Due to the COVID-19 pandemic, the course Communication Systems was transferred from presence to a virtual lecture. No hands-on lab experiments were possible. Therefore, a GNU Radio practical part was integrated into the lecture. A tutorial was written to guide students through the first steps with GNU Radio to decrease initial problems and increase student motivation. Several examples were given regarding digital signal processing, analogue and digital modulation and demodulation. Software Defined Radio receivers were set up in the amateur radio lab of the university and connected to the internet so that students were able to get real radio data to be analyzed and demodulated with their own GNU Radio models. This enables a knowledge transfer from simulated signal processing to the analysis and demodulation of real live signals. Students showed medium to high interest in practical examples during the lectures and tried their own GNU Radio simulations. Overall, the integration of GNU Radio and Software Defined Radio receivers into this virtual lecture gave additional benefits for the students to deal with signal processing and demodulation experiments. It is planned to use GNU Radio in the future for complementary practical examples to the hands-on experiments in the lab.
Physical inactivity is a problem in Europe, contributing to various non-communicable diseases (NCDs). While health sciences offer data and models for preventing the development of NCDs through health promotion, they do not explain the dynamics between the different institutions and actors in the health field. Neofunctionalism refers to these different actors and suggests that their interaction leads to the construction of a supranational authority, allowing the actors to cooperate on common policies, rules and institutions, resulting in integration and Europeanization. Indeed, there are a variety of European Union (EU) institutions and policies concerned with physical activity (PA), however, the purpose of this paper is to analyze if Europeanization and integration are happening in PA promotion, through the lens of neofunctionalism. Analysis uses process tracing for investigating the emergence of PA on the EU agenda, the legal background, existing policies and institutions. Findings indicate that Europeanization and integration of PA promotion are happening, although the opportunity for actions of the EU are restricted to voluntary actions of the EU Member States due to the agreements in the Treaty of Lisbon. This only allows the EU institutions to apply soft law approaches on PA promotion, which seems to be implemented in some Member States despite its non-binding character. The findings are discussed and further implications for public health professionals and policies outlined.
Defining Criteria for Guiding Cancer Patients to Find a Reputable Complementary Medicine Provider
(2020)
Purpose: Even in cases of positive evidence for complementary medicine (CM) therapies, it is still difficult for cancer patients to identify reputable providers. The aim of this study was to develop and evaluate a criteria list to provide guidance to cancer patients seeking a reputable CM provider.
Methods: The design combined a literature review, an expert consensus procedure (n=15) and an assessment from three stakeholder perspectives (patients (n=18), CM providers (n=26) and oncology physicians (n=20)).
Results: A total of 30 existing CM criteria were extracted from the literature, and 12 more were added by the experts. The main challenge was to define criteria that could easily be applied by the patients. A final comprehensive list of 8 criteria guiding cancer patients to find a reputable CM provider was developed.
Conclusion: Health professionals and cancer information services might find the criteria list helpful when aiming to strengthen patients' awareness of quality-related factors associated with CM providers. The criteria developed might be helpful when standards are established for quality assurance in CM in oncology.
Background and objective:
In this work, we present a systematic review concerning the recent enabling technologies as a tool to the diagnosis, treatment and better quality of life of patients diagnosed with Parkinson's Disease (PD), as well as an analysis of future trends on new approaches to this end.
Methods:
In this review, we compile a number of works published at some well-established databases, such as Science Direct, IEEEXplore, PubMed, Plos One, Multidisciplinary Digital Publishing Institute (MDPI), Association for Computing Machinery (ACM), Springer and Hindawi Publishing Corporation. Each selected work has been carefully analyzed in order to identify its objective, methodology and results.
Results:
The review showed the majority of works make use of signal-based data, which are often acquired by means of sensors. Also, we have observed the increasing number of works that employ virtual reality and e-health monitoring systems to increase the life quality of PD patients. Despite the different approaches found in the literature, almost all of them make use of some sort of machine learning mechanism to aid the automatic PD diagnosis.
Conclusions:
The main focus of this survey is to consider computer-assisted diagnosis, and how effective they can be when handling the problem of PD identification. Also, the main contribution of this review is to consider very recent works only, mainly from 2015 and 2016.