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Open Data Workshop
(2023)
ChatGPT – Freund oder Feind?
(2023)
ChatGPT 4.0 – friend or foe?
(2023)
Automatic classification of a full-thickness macular hole in optical coherence tomography images
(2023)
ChatGPT 4.0 – friend or foe?
(2023)
ChatGPT – friend or foe?
(2023)
ChatGPT – Freund oder Feind?
(2023)
A Turbulent Context
(2023)
Interface with WP123200
(2023)
Regeneration of bone defects is often limited due to compromised bone tissue physiology. Previous studies suggest that engineered extracellular matrices enhance the regenerative capacity of mesenchymal stromal cells. In this study, we used human-induced pluripotent stem cells, a scalable source of young mesenchymal progenitors (hiPSC-MPs), to generate extracellular matrix (iECM) and test its effects on the osteogenic capacity of human bone-marrow mesenchymal stromal cells (BMSCs). iECM was deposited as a layer on cell culture dishes and into three-dimensional (3D) silk-based spongy scaffolds. After decellularization, iECM maintained inherent structural proteins including collagens, fibronectin and laminin, and contained minimal residual DNA. Young adult and aged BMSCs cultured on the iECM layer in osteogenic medium exhibited a significant increase in proliferation, osteogenic marker expression, and mineralization as compared to tissue culture plastic. With BMSCs from aged donors, matrix mineralization was only detected when cultured on iECM, but not on tissue culture plastic. When cultured in 3D iECM/silk scaffolds, BMSCs exhibited significantly increased osteogenic gene expression levels and bone matrix deposition. iECM layer showed a similar enhancement of aged BMSC proliferation, osteogenic gene expression, and mineralization compared with extracellular matrix layers derived from young adult or aged BMSCs. However, iECM increased osteogenic differentiation and decreased adipocyte formation compared with single protein substrates including collagen and fibronectin. Together, our data suggest that the microenvironment comprised of iECM can enhance the osteogenic activity of BMSCs, providing a bioactive and scalable biomaterial strategy for enhancing bone regeneration in patients with delayed or failed bone healing.
MS SPIDOC is a novel sample delivery system designed for single (isolated) particle imaging at X-ray Free-Electron Lasers
that is adaptable towards most large-scale facility beamlines. Biological samples can range from small proteins to MDa
particles. Following nano-electrospray ionization, ionic samples can be m/z-filtered and structurally separated before being
oriented at the interaction zone. Here, we present the simulation package developed alongside this prototype. The first part
describes how the front-to-end ion trajectory simulations have been conducted. Highlighted is a quadrant lens; a simple but
efficient device that steers the ion beam within the vicinity of the strong DC orientation field in the interaction zone to ensure
spatial overlap with the X-rays. The second part focuses on protein orientation and discusses its potential with respect to
diffractive imaging methods. Last, coherent diffractive imaging of prototypical T = 1 and T = 3 norovirus capsids is shown.
We use realistic experimental parameters from the SPB/SFX instrument at the European XFEL to demonstrate that low-
resolution diffractive imaging data (q < 0.3 nm −1 ) can be collected with only a few X-ray pulses. Such low-resolution data
are sufficient to distinguish between both symmetries of the capsids, allowing to probe low abundant species in a beam if
MS SPIDOC is used as sample delivery.
Background
Online symptom checkers are digital health solutions that provide a differential diagnosis based on a user’s symptoms. During the coronavirus disease 2019 (COVID-19) pandemic, symptom checkers have become increasingly important due to physical distance constraints and reduced access to in-person medical consultations. Furthermore, various symptom checkers specialised in the assessment of COVID-19 infection have been produced.
Objectives
Assess the correlation between COVID-19 risk assessments from an online symptom checker and current trends in COVID-19 infections. Analyse whether those correlations are reflective of various country-wise quality of life measures. Lastly, determine whether the trends found in symptom checker assessments predict or lag relative to those of the COVID-19 infections.
Materials and methods
In this study, we compile the outcomes of COVID-19 risk assessments provided by the symptom checker Symptoma (www.symptoma.com) in 18 countries with suitably large user bases. We analyse this dataset’s spatial and temporal features compared to the number of newly confirmed COVID-19 cases published by the respective countries.
Results
We find an average correlation of 0.342 between the number of Symptoma users assessed to have a high risk of a COVID-19 infection and the official COVID-19 infection numbers. Further, we show a significant relationship between that correlation and the self-reported health of a country. Lastly, we find that the symptom checker is, on average, ahead (median +3 days) of the official infection numbers for most countries.
Conclusion
We show that online symptom checkers can capture the national-level trends in coronavirus infections. As such, they provide a valuable and unique information source in policymaking against pandemics, unrestricted by conventional resources.
Electrolytic capacitors have the disadvantage of
pronounced aging. Non-electrolytic capacitors are therefore used
in applications where long-life is important. In this paper we
present a driving stage for LEDs without any capacitive
elements. The basic topology is a Buck converter with one coil,
one active, and one passive switch. Instead of the output
capacitor, series connections of one or more LEDs and an active
switch are connected. An additional diode is connected between
the output and the input to achieve a current path, when all LED-
paths are off. A nonlinear hysteresis controller is used to achieve
a robust control. A system with three switchable LED-strings is
analyzed. Design hints are given and the function is proved with
the help of LTSpice simulations. The system can be used for
lighting purposes with the possibility to change the chrominance.
The potentiality to transmit data is also treated.
Technologiemanagement
(2023)
Stellhebel beim Aufbau von Corporate Start-ups. Dargestellt am Start-Up-Projekt „Hallo Sonne“
(2023)
Bucket increasing trees are multilabelled generalizations of increasing trees, where each non-leaf node carries b labels, with a fixed integer. We provide a fundamental result, giving a complete characterization of all families of bucket increasing trees that can be generated by a tree evolution process. We also provide several equivalent properties, complementing and extending earlier results for ordinary increasing trees to bucket trees. Additionally, we state second order results for the number of descendants of label j, again extending earlier results in the literature.
Dieser Beitrag soll interessierten Laien eine Hilfestellung an die Hand geben, ihre Infomaterialien barriereärmer zu gestalten. Einführend erfolgt eine kurze Darstellung der rechtlichen und gesellschaftlichen Situation rund um das Thema Behinderung. Verschiedene Ebenen von Barrieren und Lösungsansätze werden vorgestellt: Organisationale Barrieren von Bildungseinrichtungen werden ebenso wie Barrieren rund um das Bildungsberatungsgespräch adressiert. Der Schwerpunkt liegt bei auf der Gestaltung von Informationsmaterial. Neben einem theoretischen Hintergrund über Lösungsansätze werden praktische Umsetzungen für verschiedene Medien vorgestellt. Der Beitrag wird durch Beispiele guter Praxis in der Umsetzung, eine Checkliste zur Anwendung und weiterführende Ressourcen abgerundet.
A Model-Based Approach for Remote Development of Embedded Software for Object Avoidance Applications
(2023)
Using nylon bag techniques, Cornell net carbohydrates and protein systems (CNCPS), and scanning electron microscopy, the authors examined the digestibility and structure of Vicia ervilia (ervil, bitter vetch) after steam flaking, roasting, and microwave processing. During the in situ technique, the samples were incubated at 0, 2, 4, 6, 8, 12, 16, 24, 36, and 48 h. For the description of the ruminal DM (dry matter) and CP (crude protein) degradation kinetics of treated and untreated Vicia ervilia, different models were selected as the best fit for the dry matter (DM) and crude protein (CP) degradation parameters of steam flaked samples. The results showed that both the steam flaking and microwave treatment samples contained high levels of non-protein nitrogen and buffer soluble protein, respectively. In comparison with steam flaking and microwave treatment, roasting decreased and increased the buffer soluble protein and neutral detergent insoluble protein, respectively. The control treatments showed the highest levels of neutral detergent soluble protein and the lowest levels of acid detergent soluble protein. Moreover, steam flaking and roasting decreased and increased the amount of acid detergent insoluble protein, respectively. When using dry heat (microwave and roasting), the acid detergent soluble and insoluble protein fractions were increased. As a result of this experiment, the nitrogen fractions were altered using heat processing. Hence, protein fermented feed and ruminal fermentation conditions can be expressed using these results.
Greenhouse Gas Emission Reduction Potential of Lavender Meal and Essential Oil for Dairy Cows
(2023)
This research aims to evaluate the potential of lavender meal (LM) and lavender essential oil (LEO) to mitigate methane emissions by dairy cows. Locally grown lavender was collected fresh for this purpose, and its oil was extracted using the cold-press method. The resultant LEO and LM and whole lavender (WL) were added to dairy cow concentrate feed at 0%, 0.05%, and 0.10%, and their effects on vitro gas production values and gas concentrations were subsequently assessed. Out of the 30 bioactive compounds isolated from LEO, linalool and linalyl acetate were the most common—accounting for 70.4% of the total. The lavender dose had a significant influence on gas production for up to 12 h. No significant variations were found across the lavender forms when gas kinetics, in vitro degradability, and predicted energy values were compared. The addition of WL to the concentrate feed of dairy cows produced the greatest quantities of methane, carbon dioxide, and hydrogen sulfide, whereas LEO resulted in the lowest values. In contrast, no significant difference in ammonia content was found across the various lavender forms added into dairy cow concentrate feed. The results of this research suggest that adding 0.05–0.10% LM and LEO to concentrate feed may decrease greenhouse gas emissions from dairy cows.
We explore the different notions of completeness applied in the EPR discussion following and amending the thorough analysis of Arthur Fine. To this aim, we propose a classification scheme for scientific theories that provides a methodology for analyzing the different levels at which interpretive approaches come into play. This allows us to contrast several concepts of completeness that operate on specific levels of the theory. We introduce the notion of theory completeness and compare it with the established notions of Born completeness, Schrödinger completeness and bijective completeness. We relate these notions to the recent concept of ????-completeness and predictable completeness. The paper shows that the EPR argument contains conflicting versions of completeness. The confusion of these notions led to misunderstandings in the EPR debate and hindered its progress. Their clarification will thus contribute to recent debates on interpretational issues of quantum mechanics. Finally, we discuss the connection between the EPR paper and the Einstein–Rosen paper with regard to the question of completeness.
DC/DC-Konverter wandeln eine Eingangsspannung in eine Ausgangsspannung. In diesem Beitrag werden drei solche Konverter behandelt, die aus den drei Grundschaltungen hergeleitet sind. Im Gegensatz zu den Originalstrukturen sind diese nur für einen geringeren Spannungsübersetzungsbereich geeignet, haben aber den Vorteil, dass die elektronischen Schalter immer bei Strom null schalten und die Dioden nicht zwangsweise, sondern immer von selbst ausschalten. Die Gewinnung der Konverterschaltungen wird erläutert, und die Funktionsweisen werden durch mathematische Beschreibung, durch Skizzen und mithilfe des uZ-i-Diagramms erklärt. Weiters werden einige mögliche Erweiterungen der Schaltungen gezeigt.
The use of fault detection and tolerance measures in wireless sensor networks is inevitable to ensure the reliability of the data sources. In this context, immune-inspired concepts offer suitable characteristics for developing lightweight fault detection systems, and previous works have shown promising results. In this article, we provide a literature review of immune-inspired fault detection approaches in sensor networks proposed in the last two decades. We discuss the unique properties of the human immune system and how the found approaches exploit them. With the information from the literature review extended with the findings of our previous works, we discuss the limitations of current approaches and consequent future research directions. We have found that immune-inspired techniques are well suited for lightweight fault detection, but there are still open questions concerning the effective and efficient use of those in sensor networks.
This study aimed to assess the impact of essential oils (EOs) on in vitro gas formation and the degradability of dairy and beef cattle diets. This study also aimed to investigate the effects of different types of EOs on nutrient utilization and rumen microbial activity. The current study was conducted using a fully randomized design consisting of eight experimental treatments, including two control treatments without any additives, and treatments with cinnamon essential oil (CEO), flaxseed essential oil (FEO), and lemon seed essential oil (LEO) at a concentration of 60 mg/kg fresh mass. Two control treatments were used, one with alfalfa silage and dairy concentrate (DC, CON-DC) and the other with alfalfa silage and fattening concentrate (FC, CON-FC). Gas formation, dry matter (DM) digestibility, crude protein (CP) digestibility, effective degradability (ED), and soluble fractions of DM and organic matter (OM) were evaluated. CEO had a substantial effect on gas formation (p < 0.05). When EOs were added to the diets, they increased dry matter digestibility after 24 h of incubation as compared to control treatments. After 24 h of incubation, FCCEO and FCFEO had the highest CP digestibility among the diets. FCLEO considerably enhanced ED, as well as the soluble fraction of DM (a) at a passage rate of 2% per hour. Treatment with FCCEO resulted in a significant increase in soluble fractions compared to the control diets. At a passage rate of 2% h, DCCEO had the maximum ED value. When EOs were introduced to the diet, they dramatically decreased the insoluble portion of CP (b). Compared to the control treatments, gas production was significantly lower in the presence of LEO (FCLEO; p < 0.05). The addition of EOs to cattle diets may increase nutrient utilization and enhance rumen microbial activity. EOs extracted from lemon seeds (at a dose of 60 mg/kg of diet) lowered gas production in both dairy cattle and fattening diets.