Technische Universität Dresden: Qucosa
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Supply Chain Disruption Models: a Critical Review
No full textEnterprises affected by supply chain disruptions have reported adverse consequences and dramatic financial losses. Within the research area of supply chain risk management, researchers use simulation models and algorithms to analyze disruption risks and their potential effects on the supply chain. Supply chain disruption risk models focus on ways to quantify and assess disruption risks, study interdependencies between them, and explore the dynamic behavior of risks as they propagate through the network. So far, no review has covered and evaluated quantitative decision models which focus on these specific network-related risk characteristics. This paper derives a definition for supply chain disruption risk odels and analyzes existing approaches on the basis of requirements derived from the literature. Its aims are to structure existing approaches, reveal their shortcomings, and guide future research efforts to improve prospective models systematically. This analysis reveals potential improvements regarding the simultaneous integration of dynamic and interdependent aspects of disruption risks in the supply chain model as well as their propagation through the network. More process steps of a supply chain risk management framework should be supported and more mitigation strategies should be incorporated to expand the scope and usefulness of the models
How many species of Rafflesia exist in Java, Indonesia and what are the implications for conservation?
No full textSocietal Impact Statement:
Clarifying species status for closely related taxa with similar and overlapping morphology is important for planning conservation efforts. Conservation of Rafflesia goes beyond merely saving species from extinction. It has far-reaching societal impacts that touch on scientific discovery, cultural heritage, economic development, education, and more. Rafflesia interests many nature lovers, and so protected areas that preserve Rafflesia can become tourism hotspots, contributing to local economies and livelihoods. By conserving biodiversity, we acknowledge and value the interdependence of all living organisms, promoting a holistic understanding of nature. Biodiversity conservation is an investment in the health and well-being of both ecosystems and human societies.
Summary:
- Species ambiguity could hinder conservation activities. Rafflesia is an endangered, holoparasitic, and endophytic plant genus that grows exclusively on Tetrastigma (Vitaceae) host plants.
- Overlapping morphological characters make their species delimitation difficult. Therefore, the number of Rafflesia species has been a major debate until now. On the island of Java, Indonesia, two or three species have been variously recognized.
- Here, we aim to illuminate the species status using single nucleotide polymorphisms (SNPs) marker obtained via a multiplexed ISSR genotyping by sequencing (MIG-seq) approach. Clustering analysis with STRUCTURE indicates three different groups. Furthermore, the delimitation of the Javanese Rafflesia into three species is the favored model based on SNAPPER analysis. Phylogenetic analysis using Randomized Axelerated Maximum Likelihood (RAxML) also supports the distinction of the three groups. Although a SplitsTree4 analysis confirms the abovementioned results, it also highlights that Rafflesia patma shows broader gene flow compared to the other two species R. rochusenii and R. zollingeriana.
- We conclude that there are likely three species of Rafflesia on Java. Our study highlights the ability of using SNPs markers, in this case derived from a MIG-seq approach, in approaching species uncertainty. The importance of clarifying the Rafflesia species status on Java Island for conservation planning is also discussed
Experimentelle Tragsicherheitsbewertung an Spannbeton-Hohlkammerplatten nach einer unplanmäßigen Abweichung vom Sanierungskonzept
No full textAn einem in den 1970er Jahren errichteten, fünfgeschossigen Stahlbetonskelettbau wurden im Rahmen einer umfassenden Generalsanierung weitreichende Baumaßnahmen durchgeführt. Das weiterhin als Schulgebäude dienende Bauwerk soll dabei umgebaut und durch zusätzliche Anbauten erweitert werden. Im Zuge einer Bewehrungsabnahme wurde festgestellt, dass zusätzliche Bewehrungsanschlüsse für die geplanten Aussteifungskerne vorbereitet wurden, die jedoch nicht der Ausführungsplanung entsprachen. Stattdessen wurden die Hohlkammern eines signifikanten Anteils der als Decken dienenden Spannbetonfertigteilplatten im Auflagerbereich oberseitig aufgestemmt bzw. eingefräst, um zusätzliche Bewehrungseisen einzulegen. In diesem Beitrag wird auf eine mögliche Beeinträchtigung der Tragfähigkeit der bestehenden Deckenplatten infolge der unplanmäßigen Eingriffe eingegangen. Dabei stehen die Analyse der Deckenplatten mittels zerstörungsfreier Prüfverfahren, die durchgeführten Sanierungsmaßnahmen sowie die experimentellen Prüfungen zur Bewertung des Erfolgs dieser Ertüchtigung im Fokus
Wirklichkeitsnahe Eigenfrequenzen mittels moderner Messmethoden und KI-Tools in der Brückendynamik
No full textFür Problemstellungen in der Brückendynamik können moderne Messmittel im Zuge der Brückenhauptprüfung eingesetzt werden. Die Verarbeitung der Messergebnisse kann dabei durch ein Kl-gestütztes Tool erfolgen. Das Ergebnis ist ein verbessertes Verfahren zum Nachweis der Resonanz für Bestandsbauwerke nach DB-Handbuch 80500. Ein Ziel ist dabei ein Nachweis zur Erhöhung der Streckengeschwindigkeit. Die Validierung kann über gemessene Brücken der DB AG erfolgen.Anmerkung: Teile dieses Beitrages wurden bereits im Rahmen der 20. Fachtagung Konstruktiver Ingenieurbau 2024 der VDEI Akademie als Vortrag vorgestellt
Putting “Us” in Place: a Contrapuntal “Position” on Research Access in OverResearched Contexts
No full textThis article centers the labor aid workers perform to manage researchers in the humanitarian aid sector in Jordan. It examines how workers move and manage researchers’ bodies (including the author’s) as part of their daily job routines. Drawing from sociological and postcolonial scholarship on labor and the body to document the latter highlights multiple “knowledge producers” that shape and contest data collection in this context. The goal in describing this process is twofold. First, this article seeks to elaborate understandings of power relations in data collection processes, particularly in postcolonial settings considered over-researched. Second, it aims to broaden the scope and utility of analytic reflexivity through contrapuntal thinking about researchers’ positions in the research process
Using 360° video to create immersive virtual reality teaching materials: A virtual field trip to the Swiss Alps to assess stream water sources
No full textThe use of 360° video embedded within teaching materials has seen increasing use due to its immersive and interactive features. Embedding 360° video into virtual reality teaching materials creates a more realistic experience of dynamic environments than photos and photo panoramas because of their ability to capture motion and therefore creates a richer virtual experience within the learning resource
Using outcrop digital models to guide subsurface studies for CO2 storage: An example from the Amellago Oolitic Ramp (Mo-rocco) as an analogue for the Paris Basin Dogger Reservoir
No full textUnderstanding subsurface reservoirs remains an important objective for the future when considering carbon capture and storage (CCS) solutions for reducing greenhouse gas emissions. As with traditional subsurface studies, methods and techniques to characterise reservoirs for CCS are the same; utilising cores, well logs and/or seismic data, overseen by conceptual geological model. However, the lack of data for characterising geobodies, at the core of the reservoir, oblige geologists to use outcrop analogues
Digital outcrop mapping of the Puga geothermal field, Ladakh, India
No full textThe Puga geothermal field, located at ~4400 m elevation within exhumed ultra-high pressure gneisses of the Tso Morari nappe (Ladakh, western Himalayas), presents one of the most prospective high-enthalpy geothermal energy resources in India (GUPTA et al., 1974). It has been extensively characterised with geophysical and hydrogeochemical methods, but remains relatively poorly understood from a geological perspective
Beliefs about stress moderate the association between COVID-19-related work demands and burnout symptoms in physicians
No full textThe present study set out to investigate the role of different stress beliefs (positive and negative beliefs about stress, as well as perceived control) on the association between central COVID-19-related work demands and burnout symptoms in physicians during the second lockdown of the SARS-CoV-2 pandemic. N = 154 practicing physicians (mean [SD] age = 37.21 [9.43] years]; 57.14% female) participated in our cross-sectional German-wide online survey and answered questions about sociodemographic factors, their current work situation, their stress beliefs, and their current burnout symptoms. Moderation analyses revealed significant interaction effects between stress beliefs and specific COVID-19-related work demands on the prediction of burnout symptoms, most consistent with respect to perceived control. Positive believes about stress and its controllability were cross-sectional associated with reduced, negative believes about stress however with enhanced associations between COVID-19-related work demands and burnout symptoms. This finding indicates, if confirmed by longitudinal research, the potential of the usage of stress beliefs in prevention programs for physicians in order to mitigating negative effects of chronic stress
Exhaustion and cardiovascular risk factors: the role of vagally-mediated heart rate variability
No full textPurpose:
Exhaustion symptoms are known to be associated with cardiovascular disease (CVD) risk; however, the underlying mechanisms remain unclear. Autonomic imbalance, as indicated by reductions in vagally-mediated heart rate variability (vmHRV), appears to be a valid candidate for such a biological link, as it has been associated with both exhaustion symptoms and CVD risk and mortality.
Methods:
The present study examined a potential mediation of vmHRV on the association between exhaustion symptoms and self-reported CVD risk factors as well as the age dependency of this mediation in a large, heterogeneous sample of the Dresden Burnout Study (N = 388; 72.9% females; Mage = 42.61, SD = 11.67).
Results:
Results indicate that exhaustion symptoms were indirectly associated with CVD risk factors through vmHRV even after adjusting for well-known confounders (i.e., sex, body mass index, depressive symptoms). Moreover, this pattern was significant only among middle-aged (i.e., 54.27 years) and older individuals.
Conclusions:
Our findings add to growing evidence that autonomic imbalance may be a key biological link between exhaustion symptoms and CVD risk in middle-aged and older individuals. Implications for public health are discussed