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Die kritische Auseinandersetzung mit Werkstoffeigenschaften und potenziellen Nebenwirkungen von in einer Therapie verwendeten Materialien ist obligat für Zahnmediziner*innen. Die Freisetzung von Monomeren aus alltäglich genutzten Kunststoffen und deren Einflüsse auf den menschlichen Organismus sind ein breit diskutiertes Thema. Die Kieferorthopädie bedient sich diverser Werkstoffe, unter anderen acrylhaltige Polymeren. Ziel dieser In-vitro-Studie war der qualitative und quantitative Nachweis der Monomerfreisetzung aus dentalen Adhäsiven. Im Fokus der Untersuchung standen fünf kieferorthopädische Materialien verschiedener Indikationen, die primär in der Behandlungsphase mit festsitzenden Apparaturen Anwendung finden: BrackFix® (VOCO, Cuxhaven, Deutschland), Triad® Gel (DeguDent, Hanau, Deutschland), Transbond™ XT, LR und Plus (3M Unitek, Monrovia, CA, USA). Konform mit DIN EN ISO 10993-13 und weiteren Schritten der Standardisierung wurden Probekörper über einen Zeitraum von fünf Wochen im Elutionsmedium Kunstspeichel (Typ Fusayama) bei Körpertemperatur (37 °C) gelagert. Die anschließende Analyse der Proben auf freigesetzte Monomere wurde mittels Hochleistungsflüssigkeitschromatographie (HPLC) durchgeführt. Die Weiterverarbeitung der Daten erfolgte mit Hilfe von Shimadzu Class VP 4.7 (Shimadzu, Kyoto, Japan), Excel for Mac 16.23 (Microsoft, Redmond, WA, USA), SPSS Statistics 26 (IBM, Armonk, NY, USA) und OriginPro 2019 (OriginLab, Northampton, MA, USA). Die Freisetzung verschiedener Substanzen war bei allen Materialien über den Untersuchungszeitraum von fünf Wochen nachweisbar. Neben der Elution von gering konzentrierten und nicht identifizierten Substanzen erfolgte eine qualitative und quantitative Analyse für Bisphenol-A (BPA), Triethylenglycoldimethacrylat (TEGDMA) und Urethandimethacrylat (UDMA). BPA eluierte aus Transbond™ Plus, - XT, - LR und BrackFix®. Die gemessenen kumulierten Mittelwerte von BPA differieren je nach Material von 16,04 ppm bis 64,83 ppm. TEGDMA eluierte aus Transbond™ LR mit einem Mittelwert von 688,61 ppm. UDMA mit einem Mittelwert von 1682,00 ppm aus Triad® Gel. Die initialen Perioden zeigten maximale Elutionsraten bei allen Materialien. Die Analyse mittels Hochleistungsflüssigkeitschromatographie konnte die Elution von drei nachweislich gesundheitsschädigenden Monomeren aus fünf kieferorthopädischen Materialien belegen. Alle gemessenen Konzentrationen unterschreiten aktuelle offizielle Grenzwerte der maximal empfohlenen Aufnahmemenge. Geringe Dosen, eine kumulative Exposition und alternative Wege der Aufnahme in den menschlichen Organismus sind bekannt und stehen unter Verdacht, gesundheitsschädigende Effekte auszulösen. Explizit junge Patient*innen im Wachstum stellen eine Risikogruppe dar. Maßnahmen zur reduzierten Exposition von Patient*innen sowie der Arbeitsschutz von zahnmedizinischen Personal sollte beachtet werden. Weitere Untersuchungen zu Elutionsprozessen und Grenzwerte sind zu diskutieren., It is compulsory for dental professionals to study properties and potential side effects of materials used during treatment. The elution of monomers from plastics in daily use and their influence on the human organism is part of an ongoing controversy. Orthodontists make use of several different materials, amongst others acrylic polymers. Goal of this in-vitro study was the identification and quantification of monomers eluting from dental adhesives, with a focus on five orthodontic materials with different indications, mostly used in treatments with fixed orthodontic appliances: BrackFix® (VOCO, Cuxhaven, Germany), Triad® Gel (DeguDent, Hanau, Germany), Transbond™ XT, - LR and - Plus (3M Unitek, Monrovia, CA, USA). In accordance with DIN EN ISO 10993-13 and further steps for standardization, specimen were immersed in artificial saliva (Type Fusayama) for a period of five weeks at body-temperature (37 °C). Aliquots were analyzed by high-pressure liquid chromatography (HPLC). For processing of the obtained data, Class VP 4.7 (Shimadzu, Kyoto, Japan), Excel for Mac 16.23 (Microsoft, Redmond, WA, USA), SPSS Statistics 26 (IBM, Armonk, NY, USA) and OriginPro 2019 (OriginLab, Northampton, MA, USA) were used. An elution of different substances from all five materials after the period of 35 days was detectable. Besides unequivocally and low-concentrated substances, an identification and quantification of BPA, TEGDMA and UDMA was conducted. Transbond™ Plus, - XT, - LR and BrackFix® eluted BPA. The cumulated mean values for BPA after five weeks differ between 16,04 ppm and 64,83 ppm, depending on the material. TEGDMA eluted from Transbond™ LR with a mean of 688,61 ppm. UDMA with a mean of 1682,00 ppm from Triad® Gel. The highest ratios of eluted substances per time unit were measured for the initial period for every material. The analysis by a high-pressure liquid chromatography confirmed the elution of three substances from five orthodontic materials, proven to be harmful to health. The detected concentrations were all below the statutory thresholds, considered health threatening by authorities. Low dose effects, a cumulated exposition and alternative ways of uptake of monomers in everyday life to the human organism should be taken into consideration. An exposure management of patients and dental professionals is indicated. Further investigations and thresholds should be open for discussion.

Motile cells inside living tissues often encounter junctions, where their path branches into several alternative directions of migration. We present a theoretical model of cellular polarization for cells migrating along one-dimensional lines, arriving at a symmetric Y-junction and extending protrusions along the different paths that emanate from the junction. The model predicts the spontaneous emergence of deterministic oscillations between competing protrusions, whereby the cellular polarization and growth alternates between the competing protrusions. The oscillations are modified by cellular noise, but remain as a dominant feature which affects the time it takes the cell to migrate across the junction. These predicted oscillations in the cellular polarization during the directional decision making process at the junction are found experimentally for two different cell types, noncancerous endothelial and cancerous glioma cells, migrating on patterned network of thin adhesive lanes with junctions.

Main goal of the study was the identification and quantitative analysis of monomer elution from materials commonly used in fixed orthodontic therapy. Studies have shown severe health effects of monomers including cytotoxic, allergenic or mutagenic potential and endocrine changes. This in vitro study focusses primarily on five resins which are usually processed intraorally and remain in the oral cavity long-term.We tested the elution of monomers from specimens (7.5 mm × 1.5 mm) immersed in artificial saliva at body temperature (37 °C) for 30 min to 5 weeks. The used method is in accordance with DIN EN ISO 10993-13. The five tested materials were BrackFix® (Voco GmbH, Cuxhaven, Germany), Triad®Gel (DeguDent GmbH, Hanau, Germany), and Transbond™ XT, LR and Plus (3M Unitek, Monrovia, CA, USA). All aliquots were analyzed using high performance liquid chromatography (HPLC). Data were statistically analyzed.All five analyzed materials eluted substances over a period of 5 weeks. Identified substances included bisphenol A (BPA), triethylene glycol dimethacrylate (TEGDMA) and urethane dimethacrylate (UDMA). BPA eluted from Transbond™ Plus, XT, LR and BrackFix®. The cumulated mean values after 35 days ranged from 16.04 to 64.83 ppm, depending on the material. TEGDMA eluted with a mean of 688.61 ppm from Transbond™ LR. UDMA with a mean of 1682.00 ppm from Triad®Gel. For each material the highest concentrations of all these substances were found in the first elution period. Other substances that were not equivocally identified or of low concentration also eluted.Using the described method, it is possible to qualitatively and quantitatively determine the in vitro elution of monomers from orthodontic materials. The concentrations of the substances identified were below the current maximum recommended intake. However, a cumulative effect and low-dose effects should be considered for both patients and dental professionals, especially for young patients. Measures to reduce exposure patients and practitioners are suggested.ZIEL: Das übergeordnete Ziel dieser Untersuchung war die qualitative und quantitative Untersuchung gebräuchlicher kieferorthopädischer Materialien hinsichtlich ihrer Monomerfreisetzung. Studien haben erhebliche gesundheitliche Auswirkungen von Monomeren nachgewiesen, etwa ihr zytotoxisches, allergenes bzw. mutagenes Potenzial und endokrine Veränderungen. Diese In-vitro-Studie konzentriert sich vor allem auf 5 Kunststoffe, die in der Regel intraoral verarbeitet werden und langfristig dort verbleiben.Untersucht wurde die Freisetzung von Monomeren aus Proben (7.5 mm × 1.5 mm), die bei Körpertemperatur (37 °C) für 30 min bis 5 Wochen in künstlichen Speichel getaucht wurden. Die dabei verwendete Methode ist konform mit DIN EN ISO 10993-13. Die 5 getesteten Materialien waren BrackFix® (Voco GmbH, Cuxhaven), Triad®Gel (DeguDent GmbH, Hanau) und Transbond™ XT, LR und Plus (3M Unitek, Monrovia/CA, USA). Alle Aliquots wurden mit Hochleistungsflüssigkeitschromatographie (HPLC) analysiert.Alle 5 analysierten Materialien eluierten Substanzen über einen Zeitraum von 5 Wochen. Zu den identifizierten Substanzen gehörten Bisphenol A (BPA), Triethylenglykol-Dimethacrylat (TEGDMA) und Urethan-Dimethacrylat (UDMA). BPA wurde aus Transbond™ Plus, XT, LR und BrackFix® eluiert. Die kumulierten Mittelwerte nach 35 Tagen reichten je nach Material von 16,04–64,83 ppm. TEGDMA eluierte mit einem Mittelwert von 688,61 ppm aus Transbond™ LR, UDMA mit einem Mittelwert von 1682,00 ppm aus Triad®Gel. Höchstwerte im Verhältnis von Menge zur Zeit der freigesetzten Substanzen wurden für jedes Material in der initialen Periode ermittelt. Weitere, nicht identifizierte sowie gering konzentrierte Substanzen wurden ebenfalls eluiert. Für jedes Material wurden die höchsten Konzentrationen all dieser Substanzen in der ersten Elutionsperiode gefunden. Andere Substanzen, die nicht eindeutig identifiziert wurden oder von geringer Konzentration waren, wurden ebenfalls eluiert.Mit der beschriebenen Methode ist es möglich, die In-vitro-Elution von Monomeren aus kieferorthopädischen Materialien qualitativ wie quantitativ zu bestimmen. Die Konzentrationen der identifizierten Substanzen lagen unterhalb der derzeit empfohlenen maximalen Aufnahmemenge. Dennoch sollten eine kumulative Wirkung und Niedrigdosiseffekte sowohl für Patienten, vor allem für junge Patienten, als auch für das zahnärztliche Personal in Erwägung gezogen werden. Maßnahmen zur Verringerung der Exposition von Patienten und Behandelnden werden vorgeschlagen.

The natural capacity of extracellular vesicles (EVs) to transport their payload to recipient cells has raised big interest to repurpose EVs as delivery vehicles for xenobiotics. In the present study, bovine milk-derived EVs (BMEVs) were investigated for their potential to shuttle locked nucleic acid-modified antisense oligonucleotides (LNA ASOs) into the systemic circulation after oral administration. To this end, a broad array of analytical methods including proteomics and lipidomics were used to thoroughly characterize BMEVs. We found that additional purification by density gradients efficiently reduced levels of non-EV associated proteins. The potential of BMEVs to functionally transfer LNA ASOs was tested using advanced in vitro systems (i.e. hPSC-derived neurons and primary human cells). A slight increase in cellular LNA ASO internalization and target gene reduction was observed when LNA ASOs were delivered using BMEVs. When dosed orally in mice, only a small fraction (about 1% of total administered dose) of LNA ASOs was recovered in the peripheral tissues liver and kidney, however, no significant reduction in target gene expression (i.e. functional knockdown) was observed.

O livro de Klaus Schönitzer, publicado em alemão em 2011, na Baviera, pode ser considerado uma contribuição necessária para destacar e relembrar a importância do zoólogo Johann Baptist von Spix nessa expedição histórica. A comunidade dos zoólogos no mundo inteiro lembra-se sempre do zoólogo bávaro devido à designação da ararinha-azul com o nome científico “ Cyanopsitta spixii ” – um exemplar empalhado foi levado por Spix e se encontra até hoje na coleção zoológica de Munique.

Os fenômenos naturais, existentes em todo o nosso planeta, podem acabar em desastres naturais quando há uma relação inadequada entre Homem e Natureza. No Brasil, um dos principais fenômenos que afetam a população são os deslizamentos de terra desencadeados por chuvas intensas. Por conta dos prejuízos econômicos, sociais e a ocorrência de perda de vidas, a identificação e o constante monitoramento de áreas de risco são extremamente importantes. Dessa forma, este trabalho objetiva identificar as áreas suscetível à ocorrência de deslizamentos de terra, no bairro Britador, localizado no município de Campos do Jordão - SP, assim como os principais fatores que favorecem à ocorrência de deslizamentos. Para tanto, foi utilizado o modelo matemático Shalstab, que analisa a estabilidade de encostas, imagens de satélite do sensor WorldView 2, e técnicas de Mineração de Dados, a fim de identificar as características relacionadas ao uso e ocupação da área em estudo. Foram simulados três cenários de suscetibilidade à deslizamentos, variando os parâmetros de entrada do modelo Shalstab. Os resultados gerados pelo modelo matemático são condizentes com a realidade observada neste bairro e comprovada pelas cicatrizes de deslizamento pré-existentes. A imagem de satélite permite ainda identificar que as alterações antrópicas em áreas de encosta, são os elementos condicionantes para a ocorrência dos desastres por deslizamento de terra.

Dissertation, Rheinisch-Westfälische Technische Hochschule Aachen, 2022; Aachen : RWTH Aachen University 1 Online-Ressource : Illustrationen, Diagramme (2022). = Dissertation, Rheinisch-Westfälische Technische Hochschule Aachen, 2022, The dissertation is part of the research field of writing in the workplace. In particular, it addresses the following research gap as postulated by Jakobs and Perrin (2014: 19) "Future writing research has to develop a more inclusive and systematic understanding of the environments in which writing takes place and with which it interacts". This gap is investigated with a focus on written parts of the work of engineers. In addtion, the study examines and compares two professional fields: engineering in science and business. The investigation is designed as a long-term study. To the knowledge of the author, there is a lack of such investigations on this topic; most studies from the field only provide short-term ‚snapshots‘ on writing in the workplace. The long-term study examines four research questions: - Research question 1: What characterizes the editing of written work components among engineers and what current challenges of text production do engineers face? - Research Question 2: How do domains, time periods, and work experience affect the professional writing among engineers? - Research Question 3: How are engineers prepared for or supported in managing writing-related tasks? - Research Question 4: What influence do disruptive events have on text-production among engineers? The corpus of data collected for the analysis of this thesis covers a period of 18 years. The surveys were conducted at different points within this period. An initial thesis of the long-term study is that contexts and person-related variables change over time and that these changes can affect written tasks and their completion. Accordingly, the comparison of samples collected at different points in time is directed toward evidence of the stability or variance of phenomena over time. A variance may mean that a phenomenon occurs with different weights and/or that trends emerge. The dissertation project is empirical-exploratory in nature. The database comprises 229 interviews, 145 hours of audio material, and 2059 transcript pages. The starting point is formed by interviews from the Aachen corpus from 2004 to 2018 (112 interviews), which were supplemented by further surveys in subsequent years. The evaluation adopts qualitative content analysis (Mayring 2010) for several dimensions: comparison by domain, the date of the survey and domain, and professional experience groups. The classification, interpretation, and discussion of the results are extend Jakobs' (2007) context model of workplace writing. The results provide a detailed insight into the subject of the study. They confirm the conceptualization of professional writing as a strongly domain-specific activity coined in the 2010s, which has undergone partly continuous and partly disruptive change over the period under consideration (2004 to 2021). The sub-studies capturing disruptive changes during the Corona pandemic are new and unique in their kind. Evaluation by time shows strong effects: There are rather few constant phenomena, such as standard writing tasks and their relevance to the completion of work and to career trajectories. Dynamics vary. Changes can be more or less continuous as well as disruptive (e.g., during the corona pandemic). Under "normal conditions," i.e., during periods without disruptive contextual changes, they become weaker or less noticeable from the inside out relative to the shells of the contextual model. In times of disruptive change (Corona study), the effects are similarly strong at different levels (organizational, workplace-related, individual-related).The strongest differentiating factor is the domain in its embedding in superordinate socio-economic, cultural, and temporal contexts. Text-production changes to different degrees and at different rates depending on the domain. The economic domain shows a greater dynamic than the scientific domain. The domain-specific differences result in particular from the motives or occasions du to which writing takes place. The influence of work experience on workplace writing is significant. However, it manifests itself primarily in domain-specific ways. Representatives of both domains see a considerable need for action in terms of training and further education for career starters as well as for the course of a professional career. On the one hand, the results of the dissertation allow a deeper understanding of the subject area and its description. On the other hand, they imply - as all research does - a need for further research. This includes studies in which the same individuals are interviewed at different points in time on the same subject as well as studies that accompany emerging subdomains. Studies on many other domains and subdomains are lacking. Further studies would have to clarify how text-productive activity differs depending on the industry (e.g., chemical industry versus IT company), the type of company (e.g., sole proprietor, SME, corporation), professional roles, and organizational-functional units (written work shares of managers and trainers, in construction, production, sales, and marketing) to be able to develop training and continuing education programs that are as demand-oriented as possible., Published by RWTH Aachen University, Aachen

Cryptocurrencies are characterized by high volatility, both in the short and long term. Experienced traders exploit this to make profits from price fluctuations by swing trading. However, this requires closely observing and analyzing the prices and trading positions at the right time. Only a few specialists, who spend time focusing on this, or optimized trading bots are able to actually make continuously profits. The autradix protocol is a selfoptimizing and self-learning parametric trading algorithm that analyzes price actions in real-time and adaptively optimizes the algorithm���s parameters to realize the user���s investment objective. Embedded in an adaptive genetic algorithm, possible parameterizations are simulated and the optimal for the investigated trading pairs are calculated. The generic trading protocol API enables coupling with various crypto exchanges and decentralized protocols. A smart contract based decentralized, trustless, and tokenized fund, controlled by a DAO, enables users to invest, operate trading agents, and to participate in the profits generated according to their share.