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Molecular Dynamics Simulations of Nitric Oxide Scattering Off Graphene
Get PDFWe performed classical molecular dynamics simulations to model the scattering process of nitric oxide, NO, off graphene supported on gold. This is motivated by our desire to probe the energy transfer in collisions with graphene. Since many of these collision systems comprising of graphene and small molecules have been shown to scatter non-reactively, classical molecular dynamics appear to describe such systems sufficiently. We directed thousands of trajectories of NO molecules onto graphene along the surface normal, while varying impact position, but also speed, orientation, and rotational excitation of the nitric oxide, and compare the results with experimental data. While experiment and theory do not match quantitatively, we observe agreement that the relative amount of kineti cenergy lost during the collision increases with increasing initial kinetic energy of the NO. Furthermore, while at higher collision energies, all NO molecules lose some energy, and the vast majority of NO is scattered back, in contrast at low impact energies, the fraction of those nitric oxide molecules that are trapped at the surface increases, and some NO molecules even gain some kinetic energy during the collision process. The collision energy seems to preferentially go into the collective motion of the carbon atoms in the graphene sheet
Fachkommunikation gestern – heute – morgen : Festschrift für Klaus Schubert
Get PDFDieser Band ist eine Festschrift zum 68. Geburtstag von Klaus Schubert, der seit 30 Jahren – zunächst an der Fachhochschule Flensburg, dann an der Universität Hildesheim – als Professor im Bereich der Fachkommunikationswissenschaft starke Impulse gesetzt und das Fach nachhaltig geprägt hat. Nicht nur durch sein Modell der vier Dimensionen der Fachkommunikation, sondern auch durch umfassende Publikationstätigkeit, unerschöpfliche Einsatzbereitschaft in der Lehre und herausragendes Engagement für die Förderung des wissenschaftlichen Nachwuchses hat Klaus Schubert die eigenständige Disziplin der Fachkommunikationswissenschaft begründet, bekannt gemacht und fortentwickelt. Seine Studierenden, Promovierenden und Fachkolleginnen und -kollegen sind dadurch nachhaltig geprägt worden.
„Fachkommunikationswissenschaft gestern, heute, morgen“ versammelt Beiträge von Klaus Schuberts ehemaligen und aktuellen Doktorandinnen und Doktoranden, Mitarbeiterinnen und Mitarbeitern und Weggefährtinnen und Weggefährten, in denen die große Diversität der Fachkommunikationswissenschaft zum Ausdruck kommt
Ein modularer Ansatz für die optimale Ausführungsplanung in industriellen Produktionsprozessen
Get PDFThis paper proposes an extended Petri net formalism as a suitable language for composing optimal scheduling problems of industrial production processes with real and binary decision variables. The proposed approach is modular and scalable, as the overall process dynamics and constraints can be collected by parsing of all atomic elements of the net graph. To conclude, we demonstrate the use of this framework for modeling the moulding sand preparation process of a real foundry plant.Dieser Beitrag schlägt einen erweiterten Petrinetz-Formalismus vor, der für die Zusammenstellung optimaler Planungsprobleme von vielfältigen industriellen Produktionsprozessen mit realen und binären Entscheidungsvariablen geeignet ist. Der vorgeschlagene Ansatz ist modular und skalierbar, da die Gesamtprozessdynamik und -beschränkungen durch Analyse und Betrachtung aller atomaren Elemente des Netzgraphen aufgestellt werden können. Der Ansatz wird abschließend für die Komposition des Planungsproblems des Formsandaufbereitungsprozesses einer realen Gießereianlage eingesetzt
Management of calves in commercial dairy farms in Mecklenburg-Western Pomerania, Germany and its impact on calf mortality and prevalence of rotavirus and Cryptosporidium parvum infections in pre-weaned calves
Get PDFIn a cross-sectional study, impact of management in dairy farms on calf mortality rates and prevalence of rotavirus and Cryptosporidium parvum in feces of calves was investigated. Sixty-two commercial dairy herds in Mecklenburg-Western Pomerania, Germany, were stratified selected in 2019. We performed in-person interviews and fecal specimens in samples of all-female calves of age 7 up to 21 days. Management data were documented on farm level. A Multiscreen Ag-ELISA was performed to determine rotavirus and Cryptosporidium parvum. Associations between two calf mortality rates, detection of C. parvum and rotavirus, and predictors were examined with GLM models. In farms with routine vaccination against respiratory diseases, 31-days mortality rate was 4.2% +/-1.26 compared to 7.6% +/-0.97 (p = 0.040) on non-vaccinating farms. Six-months mortality was lower in farms that continued feeding milk to calves during periods of diarrhea compared to farms that did not (6.9% +/-0.8 vs. 12.4% +/-2.3). In case of a routine shifting of calves from the calving box into calf boxes less C. parvum was detected compared to an individual moving of calves (33.3% +/-2.6 vs. 19.6% +/-5.3; p = 0.024). Our model confirms a positive association between occurrence of aqueous feces and frequency of detection of C. parvum (45.4% +/-23.6 vs. 21.4% +/-18.7; p < 0.001). Frequency of detection of rotavirus was lower in farms that reported a defined amount of applicated colostrum per calf than in farms that presented a range of colostrum instead of a defined amount. This study indicates the potential for mitigation of risk factors for mortality in calves
Übergänge : Ein Bericht von der Mitgliederversammlung der Deutschen Gesellschaft für Supervision und Coaching e. V. am 11. und 12. November 2022 in Hannover
Get PDFDer Bericht über die Mitgliederversammlung gliedert sich in vier Teile: Einen kurzen Bericht über die formalen Anteile der Versammlung (1), die kurze Vorstellung der mit dem Cora-Baltussen-Förderpreis ausgezeichneten Abschlussarbeiten (2), eine Paraphrase des Vortrags von Armin Nassehi (3) sowie eine kritisch-kommentierende Diskussion des Fishbowls über Führungskräfte in der klinischen Pflege (4)
Hybride Arbeit: Wo und wie wollen Mitglieder agiler Softwareentwicklungsteams zukünftig arbeiten?
Get PDFVor dem Ausbruch der COVID-19 Pandemie haben Mitglieder agiler Softwareentwicklungsteams üblicherweise gemeinsam im Büro gearbeitet. Durch die rasche Verbreitung des Coronavirus wurden diese Teams weltweit ins Home Office geschickt, um die Ausbreitung des Virus einzudämmen. Verschiedene Studien weisen darauf hin, dass viele Mitglieder agiler Softwareentwicklungsteams nach dem Ende der Pandemie nicht wieder in Vollzeit in das Büro zurückkehren wollen, sondern einen hybriden Ansatz zwischen dem Büro und dem Home Office präferieren. Das Ziel dieser Abschlussarbeit ist herauszufinden, wie Mitglieder agiler Softwareentwicklungsteams sich die Zukunft ihrer Arbeit vorstellen. Dazu wurde eine quantitative Datenerhebung in Form einer webbasierten Befragung mittels eines standardisierten Fragebogens unter Mitgliedern agiler Softwareentwicklungsteams durchgeführt. Das Ergebnis ist, dass eine flexible Wahl des Arbeitsortes erwartet wird, wobei das Home Office zukünftig der präferierte Arbeitsort sein wird. Einen Einfluss durch agile Rahmenwerke und den dazugehörigen Praktiken auf die Wahl des Arbeitsortes konnte nicht festgestellt werden. Für die Zukunft wird keine signifikante Produktivitätssteigerung durch ein hybrides Arbeitsmodell erwartet.Before the outbreak of the covid-19 pandemic, members of agile software development teams typically worked together in the office. Due to the rapid spread of the corona virus, these teams were sent to the home office globally to limit the spread of the virus. Various studies indicate that many members of agile software development teams do not want to return to the office full-time after the end of the pandemic but prefer a hybrid approach between the office and the home office. The aim of this thesis is to find out how members of agile software development teams envision the future of their work. For this purpose, a quantitative data collection was conducted in the form of a web-based survey using a standardized questionnaire among members of agile software development teams. The result is that a flexible choice of work location is expected, whereby the home office will be the preferred work location in the future. An influence of agile methods and the associated practices on the choice of work location could not be determined. No significant increase in productivity is expected in the future through a hybrid working model
Factors Associated with the Severity of Clinical Mastitis
Get PDFSevere mastitis can lead to considerable disturbances in the cows’ general condition and even to septicemia and death. The aim of this cross-sectional study was to identify factors associated with the severity of the clinical expression of mastitis. Streptococcus (Str.) uberis (29.9%) was the most frequently isolated pathogen, followed by coliform bacteria (22.3%). The majority of all mastitis cases (n = 854) in this study were either mild or moderate, but 21.1% were severe. It can be deduced that the combination of coliform pathogens and increasing pathogen shedding of these showed associations with severe mastitis. Furthermore, animal-related factors associated with severe disease progression were stages of lactation, and previous diseases in the period prior to the mastitis episode. Cows in early lactation had more severe mastitis. Ketosis and uterine diseases in temporal relation to the mastitis were associated with more severe mastitis in the diseased cows. Hypocalcemia was significantly associated with milder mastitis. As another factor, treatment with corticosteroids within two weeks before mastitis was associated with higher severity of mastitis. Knowledge of these risk factors may provide the basis for randomized controlled trials of the exact influence of these on the severity of mastitis
Predicting Visible Terms from Image Captions using Concreteness and Distributional Semantics
Get PDFImage captions in scientific papers usually are complementary to the images. Consequently, the captions contain many terms that do not refer to concepts visible in the image. We conjecture that it is possible to distinguish between these two types of terms in an image caption by analysing the text only. To examine this, we evaluated different features. The dataset we used to compute tf.idf values, word embeddings and concreteness values contains over 700 000 scientific papers with over 4,6 million images. The evaluation was done with a manually annotated subset of 329 images. Additionally, we trained a support vector machine to predict whether a term is a likely visible or not. We show that concreteness of terms is a very important feature to identify terms in captions and context that refer to concepts visible in images
Comparison of Choi, RECIST and Somatostatin Receptor PET/CT Based Criteria for the Evaluation of Response and Response Prediction to PRRT
Get PDFAim:
The most suitable method for assessment of response to peptide receptor radionuclide therapy (PRRT) of neuroendocrine tumors (NET) is still under debate. In this study we aimed to compare size (RECIST 1.1), density (Choi), Standardized Uptake Value (SUV) and a newly defined ZP combined parameter derived from Somatostatin Receptor (SSR) PET/CT for prediction of both response to PRRT and overall survival (OS).
Material and Methods:
Thirty-four NET patients with progressive disease (F:M 23:11; mean age 61.2 y; SD ± 12) treated with PRRT using either Lu-177 DOTATOC or Lu-177 DOTATATE and imaged with Ga-68 SSR PET/CT approximately 10–12 weeks prior to and after each treatment cycle were retrospectively analyzed. Median duration of follow-up after the first cycle was 63.9 months (range 6.2–86.2). A total of 77 lesions (2–8 per patient) were analyzed. Response assessment was performed according to RECIST 1.1, Choi and modified EORTC (MORE) criteria. In addition, a new parameter named ZP, the product of Hounsfield unit (HU) and SUVmean (Standard Uptake Value) of a tumor lesion, was tested. Further, SUV values (max and mean) of the tumor were normalized to SUV of normal liver parenchyma. Tumor response was defined as CR, PR, or SD. Gold standard for comparison of baseline parameters for prediction of response of individual target lesions to PRRT was change in size of lesions according to RECIST 1.1. For prediction of overall survival, the response after the first and second PRRT were tested.
Results:
Based on RECIST 1.1, Choi, MORE, and ZP, 85.3%, 64.7%, 61.8%, and 70.6% achieved a response whereas 14.7%, 35.3%, 38.2%, and 29.4% demonstrated PD (progressive disease), respectively. Baseline ZP and ZPnormalized were found to be the only parameters predictive of lesion progression after three PRRT cycles (AUC ZP 0.753; 95% CI 0.6–0.9, p 0.037; AUC ZPnormalized 0.766; 95% CI 0.6–0.9; p 0.029). Based on a cut-off-value of 1201, ZP achieved a sensitivity of 86% and a specificity of 67%, while ZPnormalized reached a sensitivity of 86% and a specificity of 76% at a cut-off-value of 198. Median OS in the total cohort was not reached. In univariate analysis amongst all parameters, only patients having progressive disease according to MORE after the second cycle of PRRT were found to have significantly shorter overall survival (median OS in objective responders not reached, in PD 29.2 months; p 0.015). Patients progressive after two cycles of PRRT according to ZP had shorter OS compared to those responding (median OS for responders not reached, for PD 47.2 months, p 0.066).
Conclusions:
In this explorative study, we showed that Choi, RECIST 1.1, and SUVmax-based response evaluation varied significantly from each other. Only patients showing progressive disease after two PRRT cycles according to MORE criteria had a worse prognosis while baseline ZP and
ZPnormalized performed best in predicting lesion progression after three cycles of PRRT
Giving Anergy a Value by the Application of an Anergy-exergy Cost Ratio in Thermo-economic Analysis of Systems that Make Thermal Energy Available
Get PDFTechno-economic analysis that allocate costs to the energy flows of energy systems are helpful to understand the formation of costs within processes and to increase the cost efficiency. For the economic evaluation, the usefulness or quality of the energy is of great importance. In exergy-based methods, this is considered by allocating costs to the exergy instead of energy. As exergy represents the ability of performing work, it is often named the useful part of energy. In contrast, the anergy, the part of energy, which cannot perform work, is often assumed to be not useful.
However, heat flows as used e.g. in domestic heating are always a mixture of a relative small portion of exergy and a big portion of anergy. Although of lower quality, the anergy is obviously useful for these applications. The question is, whether it makes sense to differentiate between exergy and anergy and take both properties into account for the economic evaluation.
To answer this question, a new methodical concept based on the definition of an anergy-exergy cost ratio is compared to the commonly applied approaches of considering either energy or exergy as the basis for economic evaluation. These three different approaches for the economic analysis of thermal energy systems are applied to an exemplary heating system with thermal storages. It is shown that the results of the techno-economic analysis can be improved by giving anergy an economic value and that the proposed anergy-cost ratio allows a flexible adaptation of the evaluation depending on the economic constraints of a system