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Benefits of Combined Fluorescence Lifetime Imaging Microscopy and Fluorescence Correlation Spectroscopy for Biomedical Studies Demonstrated by Using a Liposome Model System
No full textDrug delivery systems play a pivotal role in targeted pharmaceutical transport and controlled release at specific sites. Liposomes, commonly used as drug carriers, constitute a fundamental part of these systems. Moreover, the drug–liposome model serves as a robust platform for investigating interaction processes at both cellular and molecular levels. To advance our understanding of drug carrier uptake mechanisms, we employed fluorescence lifetime imaging microscopy (FLIM) and fluorescence correlation spectroscopy (FCS), leveraging the unique benefits of two-photon (2P) excitation. Our approach utilized giant unilamellar vesicles (GUVs) as a simplified model system for cell membranes, labelled with the amphiphilic fluorescent dye 3,3′-dioctadecyloxa-carbocyanine (DiOC18(3)). Additionally, large unilamellar vesicles (LUVs) functioned as a drug carrier system, incorporating the spectrally distinct fluorescent sulforhodamine 101 (SRh101) as a surrogate drug. The investigation emphasized the diverse interactions between GUVs and LUVs based on the charged lipids employed. We examined the exchange kinetics and structural alterations of liposome carriers during the uptake process. Our study underscores the significance of employing 2P excitation in conjunction with FLIM and FCS. This powerful combination offers a valuable methodological approach for studying liposome interactions, positioning them as an exceptionally versatile model system with a distinct technical advantage
Detection of stress using photoplethysmography
No full textStress is an important factor affecting human health, and its timely detection can significantly improve quality of life. This study addresses the current issue of identifying stress states using photoplethysmography signals obtained from the wearable Shimmer 3 sensor. The purpose of the study was to establish an effective approach for stress detection, specifically through the analysis of heart rate variability changes during different states: rest and stress. A distinctive feature of the research is the use of the air raid siren sound as a stress factor. The research methodology includes the collection and analysis of biosignals, allowing for the assessment of cardiovascular system functioning under the impact of stress factors. The results of the study demonstrated significant differences in heart rhythm indicators depending on the person's state, highlighting the potential of these metrics as a tool for health monitoring and stress detection. The paper proposes a new approach to using photoplethysmography for assessing stress responses, which may contribute to the development of personalized stress management methods
Radlogistik: Grundlagen zu Logistik und Wirtschaftsverkehr mit Lasten- und Transporträdern
No full textAus den Straßen europäischer Städte sind sie kaum noch wegzudenken: Lasten- und Transporträder. Im Personenverkehr sind sie für Einkäufe und Kindertransporte bereits Standard, ebenso im Kuriersegment sowie der Paketzustellung. Besonders in der Logistik und im Wirtschaftsverkehr liegt noch ein sehr breit gefächertes und ausdifferenziertes Einsatzpotenzial. Die Renaissance des Lastenrads als Transportmittel nimmt auch im gewerblichen Sektor an Bedeutung zu.
Das Open Access-Buch bietet in dieser Form erstmals systematisch aufbereitetes Wissen für Praktiker in Wirtschaft, Politik und Verwaltung sowie für Studierende in den Bereichen Logistik und Verkehrsplanung. Zu den einzelnen Aspekten der Radlogistik (u. a. Fahrzeuge und Technik, gewerblicher Einsatz, logistischer Einsatz, Planung, Infrastrukturen, intermodale Einbindung, Best-Practice-Beispiele, Entwicklungstrends) haben national renommierte Wissenschaftler:innen Beiträge verfasst. Dieses Buch bündelt den aktuellen Wissensstand auf Basis von Forschungsergebnissen und stellt ihn kompakt und übersichtlich dar
An Integer Programming Model to Assign Train Drivers to Good Positions in Basic Turni
No full textWe are reporting on a project on duty rostering of a train operating company in Germany. There, in the past, rostering took place on a purely individual basis. As the goal of the project, the train drivers should work according to a set of 20 essentially fixed basic turni. These plans took into effect from January 2024 on.
In this extended abstract, we are focusing on a specific task that had to be resolved within the transition process. In particular, the fixed turni are intended to repeat periodically, most of them after 17 weeks. In particular, for that one turnus is equipped with train drivers in a balanced way, 17 employees have to be assigned to this turnus, each of them to one of the 17 different weeks of the turnus to start. To cover each day of the week, the weeks of the turnus typically differ in their number of working days.
Since the holidays of the train drivers had been already planned in advance, depending on the starting week, during the entire year, a smaller or larger number of working days of the turnus could be erased by the individual holidays. In order to preserve as many working days as necessary, a straightforward mixed-integer linear optimization problem has been designed and solved, to decide which train driver should start to work in which week of the turnus. The solution of this optimization run has been finally applied in practice
Human-heart-model for hardware-in-the-loop testing of pacemakers
No full textTo guarantee the safety of medical devices, including embedded systems, it is essential to consider both electronic components and the natural environment during validation and verification. In contrast to prior research, we present a hardware-in-the-loop environment that connects a real medical system to a biological model in real time for validation, including the modeling of the mechanical component of the heart valves in addition to the modeling of the electrical conduction and electrical stimulation of the heart chambers. Our model accounts for the dynamic adaptation of the temporal processes in the heart chambers to the pacing frequency of the individual chambers as a function of the action potential. This study investigates two additional risk factors affecting the heart under different conditions: pacemaker syndrome and electrical stimulation during the vulnerable phase. Both can be life-threatening to the patient if left untreated.
In implementing our concept on a physical pacemaker connected to our software-based model of the heart, we discovered that the test pacemaker was unable to generate the required heart rate in three of the scenarios we tested. Additionally, our tests revealed occurrences of pacemaker syndrome and stimulation in the vulnerable phase
Hops across Continents: Exploring How Terroir Transforms the Aromatic Profiles of Five Hop (Humulus lupulus) Varieties Grown in Their Countries of Origin and in Brazil
No full textHumulus lupulus, or hops, is a vital ingredient in brewing, contributing bitterness, flavor, and aroma. The female plants produce strobiles rich in essential oils and acids, along with bioactive compounds like polyphenols, humulene, and myrcene, which offer health benefits. This study examined the aromatic profiles of five hop varieties grown in Brazil versus their countries of origin. Fifty grams of pelletized hops from each strain were collected and analyzed using HS-SPME/GC-MS to identify volatile compounds, followed by statistical analysis with PLS-DA and ANOVA. The study identified 330 volatile compounds and found significant aromatic differences among hops from different regions. For instance, H. Mittelfrüher grown in Brazil has a fruity and herbaceous profile, while the German-grown variety is more herbal and spicy. Similar variations were noted in the Magnum, Nugget, Saaz, and Sorachi Ace varieties. The findings underscore the impact of terroir on hop aromatic profiles, with Brazilian-grown hops displaying distinct profiles compared to their counterparts from their countries of origin, including variations in aromatic notes and α-acid content
Bibliotheken und KI: in den Startlöchern mit Plan oder nur vereinzelt unterwegs?
No full textSchon vor dem Meisterstück ChatGPT von OpenAI im November 2022 sammelten Bibliotheken in Deutschland auf ganz unterschiedliche Weise Erfahrungen beim Einsatz von Technologien, welche der sogenannten Künstlichen Intelligenz zuzurechnen sind. Ob auf Konferenzen, in Publikationen oder als Beschreibung im Internet, die vielen Aktivitäten sind publik, auch weil das Thema en vogue ist. Bezogen auf die inhaltliche Erschließung aktuell mit dem finnischen Open-Source-Tool annif beginnt der Reigen an der Deutschen Nationalbibliothek und ZBW – Leibniz-Informationszentrum Wirtschaft, bezogen auf Bild- und Filmauswertung an der TIB Hannover mit dem AV-Portal und der Plattform iArts, setzt sich fort mit der Bayerischen Staatsbibliothek eigenen Bavarikon-Lösung und der reichhaltigen Fotosammlung vom stern-Archiv samit der damit angebotenen Bildähnlichkeitssuche. Weitere Beispiele an Projekten und Hilfestellungen lassen sich aufzeigen, wie zur Layout- und Strukturanalyse historischer Zeitungen bis hin zur Qualitätssicherung beim Einsatz von Optical Character Recognition (OCR) an der Berliner Staatsbibliothek, im Kontext von Digital Humanities an der HU Berlin mit Quidex, im Zusammenhang mit Forschungsdaten der ORKG von der TIB Hannover, ähnlich Geoestimation Bildmaterial topographisch zuordnet etc. Große und leistungsstarke Bibliotheken mit teils eigenen Forschungs- und Entwicklungskapazitäten können bereits auf umfangreiches, teils zehnjähriges Erfahrungswissen zurückgreifen. Seit 2023 bieten zahlreiche Hochschul- und Universitätsbibliotheken zudem Unterstützung bei KI-Tools für Recherchen nach Publikationen, Schreibwerkstätten oder zu Analyse von pdf-Dokumenten ihren Zielgruppen an. Mit dem VÖBB in Berlin startete die erste Öffentliche Bibliothek, ihre Katalog- und Metadaten seit Mitte 2024 über einen Chatbot ‘erfahrbar’ zu machen. Erste informelle Arbeitsgruppen fanden sich zusammen, wie z.B. beim DINI oder in Bibliotheksverbünden. Zentralste Anlaufstelle in der Dokumentation zu KI-Ausführungen ist bislang das Bibliotheksportal, die BiblioCon jährlich verlässliche Bühne, für die Präsentation und Diskussion anliegender Themen.
Dennoch ist man im Bereich der Hochschul- und Universitätsbibliotheken weit entfernt von einer zentral orchestrierten Aufstellung der Informationseinrichtungen hierzulande zu KI-Technologien, einer Entwicklung, die sich ohnehin anschickt, durchgreifend und nachhaltig Arbeitsprozesse und die Informationslandschaft zu verändern.
Stellenweise werden Aspekte zu KI in Strategieprozessen tangiert. Erwähnt seien diese für die Berliner Staatsbibliothek, den Bibliotheksverbund KOBV, die Sektion IV des Deutschen Bibliotheksverbandes, an der UB der FU Berlin etc.
Zwei im curricularen Kontext entstandene Arbeiten aus Darmstadt von Frau Balcik und aus München/Berlin von Frau Ernst widmen sich dem Status quo mit qualitativen und quantitativen Ansätzen, und können eine Anregung sein
Linguistic and extralinguistic factors in automatic speech recognition of German atypical speech
No full textAutomatic speech recognition (ASR) has been already used in speech and language therapy, including diagnostic tasks and practice exercises for people with aphasia (PWA). The lack of relevant data makes it difficult to evaluate the algorithms’ suitability for German-speaking PWA. For the current project, four open-source ASR models were selected based on their performance on other types of atypical speech, and the details of their evaluation are presented in this paper. The four selected models are generally robust to speakers’ gender and age. The one-word recognition yields better results for words of moderate length. Speech rate should be neither too slow nor too quick for lower error rates both in words and phrases, and the latter should be also of moderate length
Cultural values and the P-O fit: comparative NLP analysis of German online job advertisements
No full textPurpose
Within the Person-Organization fit framework and Signalling Theory, this study investigates the performance of word dictionaries detecting cultural values in online job advertisements as one form of external communication of an organization. Based upon a merge of the dictionaries, a corporate value analysis of Germany is conducted.
Design/methodology/approach
The study builds on a dataset (n > 151 k) of online job advertisements which were scraped from a German job portal. It was pre-processed according to natural language processing standards. For analysing the values of an organization a dictionary based word count was applied. Therefore, the current state-of-the-art dictionaries were tested, and an enhanced dictionary was developed and translated from English to German. Finally, a cluster analysis was conducted.
Findings
This study supports the possibility of measuring cultural values in texts where the enhanced dictionary based on Ponitzovskiy shows the best results. It thereby supports the use of the Universal Value Structure model (Schwartz, 1992) as well as the Signalling Theory (Guest et al., 2021), that values spread across 10 core or 4 aggregated dimensions are communicated via online job advertisements. Finally, the study offers a profile of the German corporate culture average as well as 4 cultural clusters and separate organizations, all with different profiles.
Originality/value
This study develops an enhanced dictionary based on a large dataset of online job advertisements for analysing the external communication of values or culture of an organization for improving the Person-Organization fit
Optimization of technology processes for enhanced CMOS-integrated 1T-1R RRAM device performance
No full textImplementing artificial synapses that emulate the synaptic behavior observed in the brain is one of the most critical requirements for neuromorphic computing. Resistive random-access memories (RRAM) have been proposed as a candidate for artificial synaptic devices. For this applicability, RRAM device performance depends on the technology used to fabricate the metal–insulator–metal (MIM) stack and the technology chosen for the selector device. To analyze these dependencies, the integrated RRAM devices in a 4k-bit array are studied on a 200 mm wafer scale in this work. The RRAM devices are integrated into two different CMOS transistor technologies of IHP, namely 250 nm and 130 nm and the devices are compared in terms of their pristine state current. The devices in 130 nm technology have shown lower number of high pristine state current devices per die in comparison to the 250 nm technology. For the 130 nm technology, the forming voltage is reduced due to the decrease of HfO₂ dielectric thickness from 8 nm to 5 nm. Additionally, 5% Al-doped 4 nm HfO₂ dielectric displayed a similar reduction in forming voltage and a lower variation in the values. Finally, the multi-level switching between the dielectric layers in 250 nm and 130 nm technologies are compared, where 130 nm showed a more significant number of conductance levels of seven compared to only four levels observed in 250 nm technology