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Ohmic heating (OH) is an alternative sustainable heating technology that has demonstrated its potential to modify protein structures and aggregates. Furthermore, certain protein aggregates, namely amyloid fibrils (AF), are associated with an enhanced protein functionality, such as gelation. This study evaluates how Ohmic heating (OH) influences the formation of AF structures from ovalbumin source under two electric field strength levels, 8.5 to 10.5 and 24.0–31.0 V/cm, respectively. Hence, AF aggregate formation was assessed over holding times ranging from 30 to 1200 sunder various environmental conditions (3.45 and 67.95 mM NaCl, 80, 85 and 90 °C, pH = 7). AF were formed under all conditions. SDS-PAGE revealed that OH had a higher tendency to preserve native ovalbumin molecules. Furthermore, Congo Red and Thioflavin T stainings indicated that OH reduces the amount of AF structures. This finding was supported by FTIR measurements, which showed OH samples to contain lower amounts of beta-sheets. Field flow fractioning revealed smaller-sized aggregates or aggregate clusters occurred after OH treatment. In contrast, prolonged holding time or higher treatment temperatures increased ThT fluorescence, beta-sheet structures and aggregate as well as cluster sizes. Ionic strength was found to dominate the effects of electric field strength under different environmental conditions.
Olive oil holds significant importance in the European diet and is renowned globally for its sensory attributes and health benefits. The effectiveness of producing olive oil is greatly influenced by factors like the maturity and type of olives used, as well as the milling techniques employed. Generally, mechanical methods can extract approximately 80% of the oil contained in the olives. The rest 20% of the oil remains in the olive waste generated at the end of the process. Additionally, significant amounts of bioactive compounds like polyphenols are also lost in the olive pomace. Traditionally, heat treatment, enzymes, and other chemicals are used for the enhancement of oil extraction; however, this approach may impact the quality of olive oil. Therefore, new technology, such as pulsed electric field (PEF), is of great benefit for nonthermal yield and quality improvements.
Easy and inexpensive methods for measuring ammonia emissions in multi-plot field trials allow the comparison of several treatments with liquid manure application. One approach that might be suitable under these conditions is the dynamic tube method (DTM). Applying the DTM, a mobile chamber system is placed on the soil surface, and the air volume within is exchanged at a constant rate for approx. 90 s. with an automated pump. This procedure is assumed to achieve an equilibrium ammonia concentration within the system. Subsequently, a measurement is performed using an ammonia-sensitive detector tube. Ammonia fluxes are calculated based on an empirical model that also takes into account the background ammonia concentration measured on unfertilized control plots. Between measurements on different plots, the chamber system is flushed with ambient air and cleaned with paper towels to minimize contamination with ammonia. The aim of this study was to determine important prerequisites and boundary conditions for the application of the DTM.
We conducted a laboratory experiment to test if the ammonia concentration remains stable while performing a measurement. Furthermore, we investigated the cleaning procedure and the effect of potential ammonia carryover on cumulated emissions under field conditions following liquid manure application. The laboratory experiment indicated that the premeasurement phase to ensure a constant ammonia concentration is not sufficient. The concentration only stabilized after performing more than 100 pump strokes, with 20 pump strokes (lasting approximately 90 s) being the recommendation.
However, the duration of performing a measurement can vary substantially, and linear conversion accounts for those differences, so a stable concentration is mandatory. Further experiments showed that the cleaning procedure is not sufficient under field conditions. Thirty minutes after performing measurements on high emitting plots, which resulted in an ammonia concentration of approx.
10 ppm in the chamber, we detected a residual concentration of 2 ppm. This contamination may affect measurements on plots with liquid manure application as well as on untreated control plots. In a field experiment with trailing hose application of liquid manure, we subsequently demonstrated that the calculation of cumulative ammonia emissions can vary by a factor of three, depending on the degree of chamber system contamination when measuring control plots. When the ammoni background values were determined by an uncontaminated chamber system that was used to measure only control plots, cumulative ammonia emissions were approximately 9 kg NH3-N ha1.
However, when ammonia background values were determined using the contaminated chamber system that was also used to measure on plots with liquid manure application, the calculation of cumulative ammonia losses indicated approximately 3 kg NH3-N ha1. Based on these results, it can be concluded that a new empirical DTM calibration is needed for multi-plot field experiments with high-emitting treatments.
Hintergrund
Die Anämie hat eine hohe Prävalenz bei Patienten vor Hüftgelenkrevisionsoperation und ist mit einer erhöhten Komplikationsrate assoziiert. Die vorliegende Arbeit untersucht erstmals den Zusammenhang von Kosten, realen DRG-Erlösen und Falldeckung der präoperativen Anämie bei elektiven Hüftgelenkrevisionsoperationen.
Methoden
Für alle Patienten, die sich von 2010 bis 2017 an 2 Campi der Charité – Universitätsmedizin Berlin einer Hüftgelenkrevisionsoperation unterzogen, wurden Daten zu Patienten sowie Transfusionen, Kosten und Erlösen gesammelt. Subgruppen- und lineare Regressionsanalysen untersuchten die Falldeckung anämischer und nichtanämischer Patienten.
Ergebnisse
Von 1187 eingeschlossenen Patienten waren 354 (29,8 %) präoperativ anämisch. Insgesamt wurden 565 (47,6 %) Patienten, mit einem deutlichen Überwiegen anämischer Patienten (72,6 % vs. 37,0 %, p < 0,001), transfundiert. Kosten (12.318 € [9027;20.044 €] vs. 8948 € [7501;11.339 €], p < 0,001) und Erlöse (11.788 € [8992;16.298 €] vs. 9611 € [8332;10.719 €], p < 0,001) waren für anämische Patienten höher, die Fallkostendeckung defizitär (−1170 € [−4467;1238 €] vs. 591 € [−1441;2103 €] €, p < 0,001). Bei anämischen Patienten nahm die Falldeckung mit zunehmender Transfusionsrate ab (p ≤ 0,001). Komorbiditäten hatten keinen signifikanten ökonomischen Einfluss.
Schlussfolgerung
Die präoperative Anämie und perioperative Transfusionen bei Hüftgelenkrevisionsoperationen sind mit erhöhten Behandlungskosten und einer finanziellen Unterdeckung für Kostenträger im Gesundheitswesen verbunden. Konzepte zur Behandlung der präoperativen Anämie (z. B. Patient Blood Management) könnten mittelfristig Behandlungskosten senken.
Introduction Postoperative delirium (POD) is seen in approximately 15% of elderly patients and is related to poorer outcomes. In 2017, the Federal Joint Committee (Gemeinsamer Bundesausschuss) introduced a ‘quality contract’ (QC) as a new instrument to improve healthcare in Germany. One of the four areas for improvement of in-patient care is the ‘Prevention of POD in the care of elderly patients’ (QC-POD), as a means to reduce the risk of developing POD and its complications.
The Institute for Quality Assurance and Transparency in Health Care identified gaps in the in-patient care of elderly patients related to the prevention, screening and treatment of POD, as required by consensus-based and evidence-based delirium guidelines. This paper introduces the QC-POD protocol, which aims to implement these guidelines into the clinical routine. There is an urgent need for well-structured, standardised and interdisciplinary pathways that enable the reliable screening and treatment of POD. Along with effective preventive measures, these concepts have a considerable potential to improve the care of elderly patients.
Methods and analysis The QC-POD study is a non-randomised, pre–post, monocentric, prospective trial with an interventional concept following a baseline control period. The QC-POD trial was initiated on 1 April 2020 between Charité-Universitätsmedizin Berlin and the German health insurance company BARMER and will end on 30 June 2023. Inclusion criteria: patients 70 years of age or older that are scheduled for a surgical procedure requiring anaesthesia and insurance with the QC partner (BARMER). Exclusion criteria included patients with a language barrier, moribund patients and those unwilling or unable to provide informed consent. The QC-POD protocol provides perioperative intervention at least two times per day, with delirium screening and non-pharmacological preventive measures.
Ethics and dissemination This protocol was approved by the ethics committee of the Charité-Universitätsmedizin, Berlin, Germany (EA1/054/20). The results will be published in a peer-reviewed scientific journal and presented at national and international conferences.
A brief questionnaire for measuring alarm fatigue in nurses and physicians in intensive care units
(2023)
When exposed to hundreds of medical device alarms per day, intensive care unit (ICU) staff can develop “alarm fatigue” (i.e., desensitisation to alarms). However, no standardised way of quantifying alarm fatigue exists. We aimed to develop a brief questionnaire for measuring alarm fatigue in nurses and physicians. After developing a list of initial items based on a literature review, we conducted 15 cognitive interviews with the target group (13 nurses and two physicians) to ensure that the items are face valid and comprehensible. We then asked 32 experts on alarm fatigue to judge whether the items are suited for measuring alarm fatigue. The resulting 27 items were sent to nurses and physicians from 15 ICUs of a large German hospital. We used exploratory factor analysis to further reduce the number of items and to identify scales. A total of 585 submissions from 707 participants could be analysed (of which 14% were physicians and 64% were nurses). The simple structure of a two-factor model was achieved within three rounds. The final questionnaire (called Charité Alarm Fatigue Questionnaire; CAFQa) consists of nine items along two scales (i.e., the “alarm stress scale” and the “alarm coping scale”). The CAFQa is a brief questionnaire that allows clinical alarm researchers to quantify the alarm fatigue of nurses and physicians. It should not take more than five minutes to administer.
Introduction: Patients undergoing revision total hip surgery (RTHS) have a high prevalence of mild and moderate preoperative anemia, associated with adverse outcomes. The aim of this study was to investigate the association of perioperative allogeneic blood transfusions (ABT) and postoperative complications in preoperatively mild compared to moderate anemic patients undergoing RTHS who did not receive a diagnostic anemia workup and treatment before surgery. Methods: We included 1,765 patients between 2007 and 2019 at a university hospital. Patients were categorized according to their severity of anemia using the WHO criteria of mild, moderate, and severe anemia in the first Hb level of the case. Patients were grouped as having received no ABT, 1–2 units of ABT, or more than 2 units of ABT. Need for intraoperative ABT was assessed in accordance with institutional standards. Primary endpoint was the compound incidence of postoperative complications. Secondary outcomes included major/minor complications and length of hospital and ICU stay. Results: Of the 1,765 patients, 31.0% were anemic of any cause before surgery. Transfusion rates were 81% in anemic patients and 41.2% in nonanemic patients. The adjusted risks for compound postoperative complication were significantly higher in patients with moderate anemia (OR 4.88, 95% CI: 1.54–13.15, p = 0.003) but not for patients with mild anemia (OR 1.93, 95% CI: 0.85–3.94, p < 0.090). Perioperative ABT was associated with significantly higher risks for complications in nonanemic patients and showed an increased risk for complications in all anemic patients. In RTHS, perioperative ABT as a treatment for moderate preoperative anemia of any cause was associated with a negative compound effect on postoperative complications, compared to anemia or ABT alone. Discussion: ABT is associated with adverse outcomes of patients with moderate preoperative anemia before RTHS. For this reason, medical treatment of moderate preoperative anemia may be considered.
Background
Beta-blocker (BB) therapy plays a central role in the treatment of cardiovascular diseases. An increasing number of patients with cardiovascular diseases undergoe noncardiac surgery, where opioids are an integral part of the anesthesiological management. There is evidence to suggest that short-term intravenous BB therapy may influence perioperative opioid requirements due to an assumed cross-talk between G-protein coupled beta-adrenergic and opioid receptors. Whether chronic BB therapy could also have an influence on perioperative opioid requirements is unclear.
Methods
A post hoc analysis of prospectively collected data from a multicenter observational (BioCog) study was performed. Inclusion criteria consisted of elderly patients (≥ 65 years) undergoing elective noncardiac surgery as well as total intravenous general anesthesia without the use of regional anesthesia and duration of anesthesia ≥ 60 min. Two groups were defined: patients with and without BB in their regular preopreative medication. The administered opioids were converted to their respective morphine equivalent doses. Multiple regression analysis was performed using the morphine-index to identify independent predictors.
Results
A total of 747 patients were included in the BioCog study in the study center Berlin. 106 patients fulfilled the inclusion criteria. Of these, 37 were on chronic BB. The latter were preoperatively significantly more likely to have arterial hypertension (94.6%), chronic renal failure (27%) and hyperlipoproteinemia (51.4%) compared to patients without BB. Both groups did not differ in terms of cumulative perioperative morphine equivalent dose (230.9 (BB group) vs. 214.8 mg (Non-BB group)). Predictive factors for increased morphine-index were older age, male sex, longer duration of anesthesia and surgery of the trunk. In a model with logarithmised morphine index, only gender (female) and duration of anesthesia remained predictive factors.
Conclusions
Chronic BB therapy was not associated with a reduced perioperative opioid consumption.
Aufgrund seiner starken Umweltauswirkungen gilt der Nahrungsmittelsektor durch Effekte in Produktion, Verarbeitung, Konsum und Entsorgung gemeinhin als ein wichtiges Handlungsfeld, soll eine gesellschaftliche Transformation in Richtung Nachhaltigkeit weiter vorangetrieben werden. Insofern Ernährungsgewohnheiten sowohl ökologische Auswirkungen induzieren als auch gesundheitliche Folgen für die Verbraucher haben, sind Konzepte gefragt, die ökologische mit gesundheitlichen Indikatoren kombinieren; diese sind jedoch bislang rar. Das vorgestellte Instrument des Nutritional Footprint greift diese Problemstellung auf und verbindet jeweils vier Kernindikatoren beider Dimensionen. Mit Hilfe des Konzeptes erhalten Verbraucher einen Überblick zu Umwelt- und Gesundheitswirkungen ihrer Ernährung. Unternehmen können wiederum interne Datensätze verwalten, Benchmarking betreiben und ihre externe Kommunikationsleistung erweitern.
Werkstattbericht zum Projekt NAHGast, Fokus: ‚Leitbild nachhaltiger Gemeinschaftsverpflegung‘
(2016)
"The limits of my language are the limits of my mind. All I know is what I have words for" (Wittgenstein). When learning something completely new, we connect the unknown term to an already existing part of our knowledge. We can only build new ideas and insights upon an existing conceptual foundation. In the field of statistics, we educators frequently find ourselves met with great confusion when teaching novices. These students, entirely unfamiliar with even basic statistics, must connect the introduced statistical terms within their personal existing networks of largely non-statistical knowledge. Lecturers, on the other hand, who are well versed in statistics, have deeply internalized the content to be taught and its relevant context. The juxtaposition of the two roles may produce amusement in a lecturer upon gaining insight into the word associations made by the statistical novices. For example, a ‘logistic regression’ does not involve the ‘shipping of goods in economically difficult times,’ though this might seem entirely reasonable and intuitive to the statistics learner. Other times, these different perspectives can lead to headaches and frustration for both learners and their lecturers. In this article, we illustrate how simple statistical terms are initially connected to a student’s pre-exiting knowledge and how these associations change after completing an introductory course in applied statistics. Furthermore, we emphasize the important difference between “term”, “approach”, and “context”. Understanding this fundamental distinction may help improve the communication between the lecturer and the learner. We offer a collection of practical tools for instructors to help promote students’ conceptual understanding in a supportive, mutually-beneficial learning environment.
In diesem Buch sind Lehrbeispiele gesammelt, die Dozierenden wertvolle Anregungen für ihre eigene Lehre liefern: Es werden Ideen für einzelne Übungen, Unterrichtseinheiten, Prüfungen oder ganze Kurse vorgestellt. Die benötigten Materialien sind für die Nutzer online frei verfügbar, um die Anwendung zu vereinfachen.
Alle Beiträge dieses Buches wurden 2020 für den Preis für das beste Health-Data-Science-Lehrmaterial eingereicht, der von der Arbeitsgruppe Lehre und Didaktik der Biometrie der Deutschen Region der Internationalen Biometrischen Gesellschaft und der GMDS ausgeschrieben wurde. So entstand ein breiter Querschnitt an Beiträgen für lebendige Lehre in Biometrie, Epidemiologie, Public Health und ähnlichen Gebieten.
Das Buch knüpft damit an die beiden Bände Zeig mir Biostatistik! und Zeig mir mehr Biostatistik! an, denen ähnliche Ausschreibungen vorausgingen.
Die Herausgeber unterrichten Biometrie als Haupt- oder Nebenfach an verschiedenen Universitäten bzw. Hochschulen. Es verbindet sie das gemeinsame Ziel, den Austausch von Ideen und ausgereiftem Unterrichtsmaterial im Bereich Health Data Science zu fördern.
Die Analyse des Geschäftsberichts (Risikoberichts) zeigt, dass das Risikomanagementsystem der Wirecard AG gravierende Defizite aufwies. Man muss basierend auf den öffentlich verfügbaren Daten davon ausgehen, dass sich aus den gesetzlichen Bestimmungen nach §§ 91 und 93 AktG ergebende Anforderungen nicht erfüllt waren. Wie bei vielen anderen Unternehmen ist z. B. nicht erkennbar, dass eine Risikoaggregation durch eine geeignete Methode stattgefunden hat. Ohne eine solche Risikoaggregation ist die Frühidentifikation von „bestandsgefährdenden Entwicklungen“ aus Kombinationseffekten von Einzelrisiken nicht möglich. Trotz dieser Defizite ist allerdings nicht erkennbar, dass eine kausale Verbindung mit der späteren Insolvenz besteht. Viele der Schwächen sind auch bei anderen börsennotierten Gesellschaften „üblich“ und daher kein Indiz dafür, dass das Unternehmen einem besonderen Insolvenzrisiko, speziell durch Betrug von Vorstandsmitgliedern, ausgesetzt war. Die nach dem „alten“ IDW Prüfungsstandard 340 durchgeführte Prüfung des Risikomanagements durch EY hat bestehende „schwerwiegende Mängel“ offenbar akzeptiert. Solche Schwächen der Abschlussprüfung findet man jedoch auch bei vielen anderen Unternehmen, was empirische Studien belegen. Im vorliegenden Fall bedeutet dies, dass die gravierenden Defizite der Abschlussprüfung durch EY auch im Bereich der Prüfung des Risikofrüherkennungssystems eindeutig erkennbar waren.
The ability of film stars to attract viewers is a widely accepted rationale for hiring expensive actors. However, the precise mechanisms behind this ‘drawing power’ remain unclear. By reviewing the existing literature, six possible antecedents of drawing power are identified. Artists with high acting abilities (i) increase a film’s artistic appeal, (ii) function as markers of quality and (iii) facilitate the matching process with the right audiences. Widely popular, commonly perceived as beautiful/handsome but often less talented actors, on the other hand, rather (iv) facilitate the marketing campaigns of films, (v) offer entertaining interactions with famous personalities and (vi) provide manifold opportunities for gossiping. Based on a discussion of the implications for theory and a preliminary analysis of a sample of Hollywood actors, managerial recommendations for those who have and those who depend on star drawing power are developed.
Response of petunia to wood fibre amended peat substrate under ebb-and-flow irrigation (Abstract)
(2024)
Test von Schnellverfahren zur Bestimmung der Benetzungseigenschaften von Kultursubstraten (Abstract)
(2024)
Purpose
This paper aims to investigate the strategic consequences of manufacturing location decisions, with a focus on understanding the link between collocating manufacturing with other value chain activities, via reshoring or retaining and organizational agility.
Design/methodology/approach
The paper uses qualitative data from 115 interviews with executives from UK high value manufacturing companies to explore the recent phenomenon of reshoring and the strategic effects of manufacturing location.
Findings
The location of manufacturing is operationally and strategically important for multinational companies. The spatial dispersion of manufacturing is determined by firm-specific and external factors, both of which are subject to constant change. The analysis shows that concentrating on manufacturing in their home countries enables firms to increase organizational agility and stimulate innovation. Better integration with and more extensive collaboration between related value chain activities, such as research and development, sales and marketing, leads to higher flexibility, speed and responsiveness to customer requirements. However, under certain conditions, firms also continue to benefit from the known advantages of offshoring.
Originality/value
This research sheds light on possible strategic downsides of global value chains, characterized by dispersed activities and intermitted processes. The results provide evidence that retaining manufacturing or bringing back manufacturing operations to a company’s home country can increase organizational flexibility, speed, adaptability, innovativeness and responsiveness to customer requirements. As these capabilities are critical for long-term survival, especially in dynamic environments, firms need to review their global factory configurations and determine whether the short-term advantages of foreign locations continue to justify offshoring practices.
Enhancing the nutritional value of pears through agronomic biofortification with iodine (Abstract)
(2024)
Over the past decade, the proliferation of entrepreneurial ventures and small firms with sustainable business models have pushed the sustainability agenda in the fashion industry. Despite prominent success stories, these companies often encounter significant operative challenges that hinder growth or even cause business failure. This paper adopts a qualitative research design and uses data gathered during 18 expert interviews with entrepreneurs and executive managers of 18 firms from 13 countries to identify and explore the dominant challenges that micro- and small-sized sustainable fashion companies struggle with. The results indicate that communicating with consumers is perceived as surprisingly difficult, especially because sustainable brands need to justify higher prices and explain the added benefits of their products. Second, resource constraints lead to operative friction and overburdening of the decision makers and their small management teams. Third, sustainable sourcing and production processes are economically difficult in an industry that continues to occupy a mass and low-cost logic. Against the background of these insights, a range of managerial recommendations are developed and contextualized in the framework of the Business Model Canvas. This novel approach makes the suggestions which are rooted in the resource-based view actionable and supports sustainable businesses to better manage their operations and achieve growth. For example, collaborative approaches with different stakeholders may mitigate constraints across all three identified problem areas.
The 3GPP release 16 integrates TSN functionality into 5G and standardizes various options for TSN time synchronization over 5G such as transparent mode and bridge mode. The time domains for the TSN network and the 5G network are kept separate with an option to synchronize either of the networks to the other. The TSN time synchronization over 5G is possible either by using the IEEE 1588 generalized Precision Time Protocol (gPTP) based on UDP/IP multicast or via IEEE 802.1AS based on Ethernet PDUs. The INET and Simu5G simulation frameworks, which are both based on the OMNeT++ discrete event simulator, are widely used for simulating TSN and 5G networks. The INET framework comprises the 802.1AS based time synchronization mechanism, and Simu5G provides the 5G user plane carrying IP PDUs. We modified the 802.1AS-based synchronization model of INET so that it works over UDP/IP. With that, it is possible to synchronize TSN slaves (connected to 5G UEs), across a 5G network, with a TSN master clock, present within a TSN network, that is connected to the 5G core network. Our simulation results show that 500 microseconds of synchronization accuracy can be achieved with the corrected asymmetric propagation delay of uplink and downlink between the gNodeB (gNB) and the User Equipment (UE). Furthermore, the synchronization accuracy can be improved if the delay difference between uplink and downlink is known.
Recent real-time networking developments have enabled ultra reliability, very low latency and high data rates in wired networks. Wireless networking developments have also shown that they can achieve very high data rates with consistency, but they still lack in providing ultra reliability and extremely low latency. Time Sensitive Networking (TSN) developments have brought these capabilities in Industry automation and Automotive industry too. Although TSN is standardized for wired networks for a long time, for wireless networks it will be standardized within the IEEE 802.11be standard for Wi-Fi and 3GPP Release 17 for 5G in the near future. This paper provides an overview of TSN in wired and wireless networks with the aim of comparing different simulators and presenting their offered functionality and shortcomings. These tools can be used to make oneself familiar with TSN algorithms, standards, and for the development and testing of time sensitive networks. Afterwards, the paper discusses open research questions for using TSN over wireless networks.
This paper presents a framework for OMNeT++ which includes time synchronization model for WLANs. Synchronization is based on the Generalized Precision Time Protocol (gPTP) standard, which aims to achieve an accuracy of less than 100 nanoseconds. The presented model is developed and implemented in OMNeT++, a discrete event network simulator, using its INET library. A new type of WLAN node is modeled which supports time synchronization at the Link layer. A clock module for WLAN nodes is also modeled which implements variable clock drift to simulate noise interference in clock frequency oscillators. Simulations with our WLAN nodes are done and the results show that using gPTP based time synchronization in wireless networks, accuracy of ±3ns can be achieved.
Long Range Wide Area Network (LoRaWAN) operates in the ISM band with 868 MHz, where the Time on Air (ToA) is regulated in the EU to 1 %. LoRaWAN nodes use the Adaptive Data Rate (ADR) algorithm to adapt their data rates during operation. The standard ADR algorithm works well with stationary nodes, however is very slow in the adaptation for mobile nodes. This paper introduces a new ADR algorithm for LoRaWAN that is supported by higher level meta-data for sensor streams, namely Quality of Information (QoI). With the help of QoI it is possible to provide additional information to the new ADR algorithm, reducing the convergence time and thus improving the Packet Delivery Ratio (PDR) of data from mobile sensor nodes. The new algorithm requires only modifications on network server side and keeps backwards compatibility with LoRaWAN nodes. Results show a significant better PDR compared to the standard ADR in scenarios with a limited number of mobile nodes.
Auf vielen Landmaschinen wird der CAN-Bus zur Übertragung von Daten zwischen Sensoren, Aktoren und Steuergeräten genutzt. Anwendungen wie Rückfahrkameras und Bird-ViewAnzeigen erfordern in der Regel zusätzliche, breitbandige Kommunikationskanäle. Dieser Beitrag untersucht, inwieweit ein gemeinschaftliches Kommunikationsmedium auf Basis von Ethernet zur Realisierung aktueller und zukünftiger Anwendungen auf Landmaschinen genutzt werden kann. Zusätzlich wird der Einsatz aktueller Technologien wie Audio/Video Bridging, Time-Sensitive Networking und Wifi auf einem Landmaschinengespann untersucht und bewertet.
Analysis of methods for prioritizing critical data transmissions in agricultural vehicular networks
(2020)
Applying wireless communication technologies to agricultural vehicular networks often results in high end-to-end delays and loss of packets due to intermittent or broken connectivity. This paper analyses the methods for the successful delivery of the vehicular data within acceptable delay times. Different kinds of data that are generated and transmitted in agricultural networks are considered in this paper, followed by the data prioritization methods which allow critical data to be prioritized against other data. In this regard, Enhanced Distributed Channel Access, Differentiated Services, and application-based data rate variation are discussed in conjunction with the Simple Network Management Protocol. These techniques are simulated or tested separately and then together and the results show that even in poor network conditions, high-prioritized data is not lost or delayed.
Die Digitalisierung des Bodenbeprobungsverfahrens mit einer automatisierten Generierung einer Düngeempfehlung auf Grundlage der analysierten Bodennährstoffgehalte – direkt nach Beendigung der Bodenbeprobung auf dem Acker – ist ein übergeordnetes Ziel bei der Nutzung des mobilen Feldlabors „soil2data“. Neben den Bodennährstoffanalyse-Ergebnissen sind für die Umsetzung einer automatisierten generierten Düngeempfehlung weitere Informationen notwendig.
Die Quellen dieser Informationen haben einen unterschiedlichen Ursprung. Es sind Daten aus verschiedenen Quellen vom Bewirtschafter, von Dienstleistern und vom mobilen Feldlabor, welche miteinander verknüpft und synchronisiert werden müssen. Für einen automatisierten Prozessablauf zur Generierung einer Düngeempfehlung ist die Datenorganisation eine essenzielle Voraussetzung. Die Grundlage der Empfehlung sind die Tabellenwerke der offiziellen Düngeempfehlung, die bei den für die Düngung zuständigen Behörden der Bundesländer vorliegen. In dieser Publikation werden die notwendigen Daten und der Prozessdatenfluss für die Bodenbeprobung und Düngeempfehlung-Generierung beschrieben und grafisch dargestellt.
Knowledge of the small-scale nutrient status of arable land is an important basis for optimizing fertilizer use in crop production. A mobile field laboratory opens up the possibility of carrying out soil sampling and nutrient analysis directly on the field. In addition to the benefits of fast data availability and the avoidance of soil material transport to the laboratory, it provides a future foundation for advanced application options, e.g. a high sampling density, sampling of small sub-fields or dynamic adaptation of the sampling line during field sampling. An innovative key component is the NUTRI-STAT ISFET sensor module. It measures values for the ions "NO3- ”, “H2PO4- " and "K+ " as well as the pH. The ISFET sensor module was specially developed for soil nutrient analysis. The phosphorus measurement was further developed for the project "soil2data". First results from the ISFET sensor module show a measurement signal settling time of significantly less than 100 seconds and a further consistent stable measurement signal. The measurement signal dynamics of approx. 58 mV per factor 10 of concentration change is given for the measured variables pH and K+. For the measured quantities of NO3- and H2PO4- , the measurement signal dynamics are lower.
Die funktionale Wiedervernetzung von Ökosystemen ist ein notwendiger und entscheidender Beitrag zur nachhaltigen Sicherung der Artenvielfalt. In der nationalen Strategie zur Biologischen Vielfalt 2007 ist formuliert, dass von Verkehrswegen bis 2020 in der Regel keine erheblichen Beeinträchtigungen des Biotopverbundsystems ausgehen (sollen). In der EU-Biodiversitätsstrategie 2030 ist formuliert, dass es für ein wirklich kohärentes und resilientes transeuropäisches Naturschutznetz wichtig sein wird, ökologische Korridore zu schaffen, um eine genetische Isolierung zu verhindern, die Migration von Arten zu ermöglichen und gesunde Ökosysteme zu erhalten und zu verbessern.
Fütterung von Zuchtstuten
(2021)
Shredlage für Mastbullen?
(2021)
Shredlage in der Bullenmast?
(2021)
Mehr Milchleistung
(2021)
Flüssigfutter bei Milchkühen
(2021)
Ist die TMR zu feucht?
(2021)
Zu viel Wasser in der TMR?
(2021)
The aim of the study was to examine different pH parameters, such as variations throughout the day, depending on differing concentrate feed proportions. Moreover, special attention was payed to individual variation in microbial efficiencies (microbial crude protein/fermented organic matter) and their relation to ruminal pH, nutrient flows and digestibilities. For this, cows were grouped according to microbial efficiency (more, n = 5, vs. less efficient cows, n = 4). After calving, thirteen ruminally cannulated pluriparous cows, including nine duodenally cannulated animals, were divided into groups offered rations with a lower (35% on dry matter basis, n = 7) or a higher (60% on dry matter basis, n = 6) concentrate feed proportion. Ruminal pH parameters were assessed continuously by using intraruminal probes. Nutrient flows, nutrient digestibility and microbial efficiency were determined for duodenally cannulated cows. For most ruminal pH parameters it seemed that individual variability was higher than the treatment effect. However, a positive relationship between actual concentrate intake and diurnal pH fluctuations was found. Besides, the effect of individually different microbial efficiencies was assessed. Again, there were no group differences for pH parameters. However, nutrient flows were significantly higher in more efficient cows, whereas digestibilities were lower in in more efficient cows.
Ursachen von Kotwasser
(2021)
Wasser dosiert zusetzen
(2021)
Duckweed is a promising resource for future feed and food production as well as wastewater treatment. However, diseases and pests can critically limit the performance of the production systems. Patches of discolored and bleached duckweed (Lemna minor L.) appeared in hydroponic systems and spread rapidly through the crop. Pythium myriotylum was confirmed as the causing pathogen by microbiological and molecular biological analysis. This is the first report of P. myriotylum on duckweed in Germany. The result and possible countermeasures are discussed.
The development of non-precious metal-based electrodes that actively and stably support the oxygen evolution reaction (OER) in water electrolysis systems remains a challenge, especially at low pH levels. The recently published study has conclusively shown that the addition of haematite to H2 SO4 is a highly effective method of significantly reducing oxygen evolution overpotential and extending anode life. The far superior result is achieved by concentrating oxygen evolution centres on the oxide particles rather than on the electrode. However, unsatisfactory Faradaic efficiencies of the OER and hydrogen evolution reaction (HER) parts as well as the required high haematite load impede applicability and upscaling of this process. Here it is shown that the same performance is achieved with three times less metal oxide powder if NiO/H2 SO4 suspensions are used along with stainless steel anodes. The reason for the enormous improvement in OER performance by adding NiO to the electrolyte is the weakening of the intramolecular O─H bond in the water molecules, which is under the direct influence of the nickel oxide suspended in the electrolyte. The manipulation of bonds in water molecules to increase the tendency of the water to split is a ground-breaking development, as shown in this first example.
Wasser
(2021)
The development of base metal electrodes that can act as active and stable oxygen generating electrodes in water electrolysis systems, especially at low pH levels, remains a challenge. The use of suspensions as electrolytes for water splitting has until recently been limited to photoelectrocatalytic approaches. A high current density (j=30 mA/cm2) for water electrolysis has been achieved at a very low oxygen evolution reaction (OER) potential (E=1.36 V vs. RHE) using a SnO2/H2SO4 suspension-based electrolyte in combination with a steel anode. More importantly, the high charge-to-oxygen conversion rate (Faraday efficiency of 88% for OER at j=10 mA/cm2 current density). Since cyclic voltammetry (CV) experiments show that oxygen evolution starts at a low, but not exceptionally low, potential, the reason for the low potential in chronoamperometry (CP) tests is an increase in the active electrode area, which has been confirmed by various experiments. For the first time, the addition of a relatively small amount of solids to a clear electrolyte has been shown to significantly reduce the overpotential of the OER in water electrolysis down to the 100 mV region, resulting in a remarkable reduction in anode wear while maintaining a high current density.
Neue Futtermittel
(2021)
Ganzpflanzensilage
(2021)
Maniok und Tapioka
(2021)