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Exploring the Impact of Solid-State Fermentation on Fava Bean Flour: A Comparative Study of Aspergillus oryzae and Rhizopus oligosporus
No full textFava bean (Vicia faba L.) is a protein-rich pulse with high nutritional value, but its functional and sensory characteristics limit its application in foods. Solid-state fermentation (SSF) can modify the composition of plant proteins, modulate its functionality, and enhance the sensory aspects. In this study, fava bean flour (FB) was fermented with Aspergillus oryzae and Rhizopus oligosporus to produce FBA and FBR, respectively, ingredients with distinct nutritional, functional, and aroma characteristics. The protein content increased by 20% in FBA and 8% in FBR, while fat levels rose more significantly in FBR (+40%). The overall content of fermentable oligo-, di-, mono-saccharides, and polyols (FODMAPs) decreased by 47% (FBA) and 57% (FBR), although polyol production by A. oryzae was observed. SSF improved the nutritional profile of FBA and FBR, with a notable increase in the concentration of essential amino acids observed, and a reduction in most antinutrients, with the exception of trypsin inhibitors. SSF resulted in the formation of aggregates, which increased the particle size and reduced protein solubility. Emulsions prepared with the fermented ingredients separated faster, and the foaming capacity of both FBA and FBR was decreased, but an increase in water-holding capacity was observed. SSF resulted in the production of predominantly savoury-associated aroma compounds, with compounds characteristic of metallic and mouldy aromas reduced. These results indicate the potential of SSF to transform FB with enhanced nutritional value and improved sensory and functional properties.131
Differential microstrip line to waveguide transitions for D-band based on irises
No full text17251732D-band waveguide transitions that combine a resonant patch on the printed circuit board with multiple waveguide irises are presented and shown to achieve a relative bandwidth of up to 35%. The irises implement an impedance-matching network that is described by a lumped-element circuit model. Parametric sweeps and Monte Carlo simulations quantify the influence of iris dimensions and manufacturing tolerances. The transitions’ group delay is characterized, and its influence on time-domain signals is demonstrated. As an application example, a transition design with six irises is integrated into a multichannel radar frontend with 40 GHz bandwidth, and measured range profiles are presented. The derived design guidelines enable straightforward customization of iris-based transitions for various applications and frequency bands
Surface Integrity of Additively Manufactured Workpieces after Machine Hammer Peening
No full text161166Additively manufactured workpieces often exhibit issues such as porosity, roughness, and induced tensile residual stresses. The surface characteristics of such workpieces can be modified by post-processing techniques like Machine Hammer Peening (MHP). However, the influence of MHP on surface characteristics of additively manufactured workpieces has not been comprehensively studied. Thus, this study investigates the influence of MHP on surface integrity of workpieces created using wire-based Laser Metal Deposition (LMD-w) with Inconel 718 wire. The effect of secondary temperature on surface integrity is first evaluated. Following this, the impact of MHP process parameters on surface integrity is systematically investigated. The quantification of surface integrity is achieved by measuring its key aspects such as topography and surface layer characteristics, including surface roughness, waviness, hardness, recrystallization, and residual stresses. Microstructural analysis of the selected samples is conducted employing Scanning Electron Microscope (SEM) and optical microscopy. The obtained results provide valuable insights into the effectiveness of MHP on the surface integrity of LMD-w workpieces, along with practical guidelines for its optimization. Extending its impact, the study enhances the broader understanding of surface treatment in additive manufacturing
STED super-resolution microscopy of mitochondrial translocases
No full text299327The mitochondrial translocases of the outer membrane (TOM) and of the inner membrane (TIM) act together to facilitate the import of nuclear-encoded proteins across the mitochondrial membranes. Stimulated Emission Depletion (STED) super-resolution microscopy enables the in situ imaging of such complexes in single cells at sub-diffraction resolution. STED microscopy requires only conventional sample preparation techniques and provides super-resolved raw data without the need for further image processing. In this chapter, we provide a detailed example protocol for STED microscopy of TOM20 and mitochondrial DNA in fixed mammalian cells. The protocol includes instructions on sample preparation for immunolabeling, including cell line selection, fixation, permeabilization, blocking, labeling and mounting, but also recommendations for sample and microscope performance evaluation. The protocol is supplemented by considerations on key factors that influence the quality of the final image and also includes some considerations for the analysis of the acquired images. While the protocol described here is aimed at imaging TOM20 and DNA, it contains all the information for an immediate adaptation to other cellular targets.70
Students’ perspectives regarding needs for and opportunities with mixed-reality education in neurosurgery at German medical schools
No full textOBJECTIVE Despite mixed reality being an emerging tool for tailored neurosurgical treatment and safety enhancement, the use of mixed reality in the education of German medical students is not established in the field of neurosurgery. The present study aimed to investigate medical students’ perspectives on the use of mixed reality in neurosurgical medical education. METHODS Between July 3, 2023, and August 31, 2023, an online survey was completed by German medical students through their affiliated student associations and educational institutions. The survey included 16 items related to mixed reality in neurosurgery, with participants providing ratings on a 4-point Likert scale to indicate their level of agreement with these statements. RESULTS A total of 150 students from 27 medical schools in Germany took part in the survey. A significant majority comprising 131 (87.3%) students expressed strong to intense interest in mixed-reality courses in neurosurgery, and 108 (72%) reported an interest in incorporating mixed reality into their curriculum. Furthermore, 94.7% agreed that mixed reality may enhance their understanding of operative neuroanatomy and 72.7% agreed with the idea that teaching via mixed-reality methods may increase the probability of the use of mixed reality in their future career. The majority (116/150 [77.3%]) reported that the preferred optimum timepoint for teaching with mixed reality might be within the first 3 years of medical school. In particular, more students in the first 2 years preferred to start mixed-reality courses in the first 2 years of medical school compared to students in their 3rd to 6th years of medical school (71.9% vs 41.5%, p = 0.003). Residents and attending specialists were believed to be appropriate teachers by 118 students (78.7%). CONCLUSIONS German medical students exhibited significant interest and willingness to engage in mixed reality in neurosurgery. Evidently, there is a high demand for medical schools to provide mixed-reality courses. Students seem to prefer the courses as early as possible in their medical school education in order to transfer preclinical neuroanatomical knowledge into operative neurosurgical anatomy by using this promising technique.56
Risk Management in Production Planning: A Systematic Literature Review
No full text525536In recent years, unforeseen and rare events in the environment of manufacturing companies have been a dominating influence in production planning. Examples are dynamic product demand developments due to the COVID-19 pandemic and geopolitical conflicts or changes in production resource availabilities due to technological disruptions and shortages. In addressing these unforeseen events, large changes in the production systems can cause errors or disruptions raising the need for the inclusion of risk management in production planning. In order to insure applicability for unforeseen and rare events, risk management approaches in production planning require realistic and objective risk assessments. This paper conducts a literature review for risk management in production planning with the aim of assessing the state of the art in regards to realistic and objective risk assessment and concludes with the recommendation for further consideration of rare and unexpected events in future methodologies.Part F176
Polymer Additives
No full text409444Additives are essential components of plastic formulations providing maintenance and/or modification of polymer properties, performance and long-term use. Historically polymer additives were decisive for the development of thermoplastic material applications. This chapter presents the most important classes of additives (antioxidants, PVC heat stabilizers, light stabilizers, and flame retardants). It provides general information on chemical structures and mechanisms, on testing methods and on use examples in selected polymer classes. The chapter summarizes other important additive classes. The compounds used today as PVC heat stabilizers are based on mixed metal salts, for example calcium/zinc, organo-tin compounds, and metal-free organic-based systems. Plasticizers in the form of additives act as processing aids, reduce the melting and processing temperature of the polymer, and modify the polymer properties, for example reducing the elastic modulus and making it more flexible and softer. Impact modifiers are used to toughen rigid PVC and polystyrenes
Assessing the Human Competence and Individual Support Level in Manual Assembly through Cognitive Assistance Systems
No full text811816In today's industrial landscape, production challenges arise from increasing demand for personalized products and demographic changes. Production facilities and employees must be agile and adaptable to changing requirements, while limited automation in multi-variant production elevates the importance of human workers. Cognitive assistance systems, such as digital instructions and pick-by-light systems, can enhance efficiency and reduce errors but should be customized to worker competence levels. This article presents a method for assessing worker competence and individual support using cognitive assistance systems in manual assembly, with an example from Fraunhofer IGCV's "Learning factory for cyber-physical production systems" in Augsburg
Hierarchical pore engineering of lignocellulose-based carbon materials for electric double-layer capacitors
No full textLignocellulose is an ideal precursor for supercapacitor electrodes due to its diverse structures and abundant availability. For supercapacitors, particularly electric double-layer capacitors (EDLCs), pore structure is critical. This review summarizes advances in lignocellulose-derived hierarchical porous carbon (LHPC) for supercapacitors, focusing on pore structure and future research directions. We discuss how pore structure influences supercapacitor performance, the activation methods for creating pores in LHPC, and review studies on optimizing pore structure for high-performance supercapacitors. Hierarchical porous carbon should feature a sufficient micropore surface area along with suitable mesoporous and macroporous surfaces to enhance rate performance while maintaining capacitance. This review is expected to actively advance the selection of lignocellulosic precursors and the development of optimized pore structure models, with the ultimate goal of enabling efficient production of lignocellulose-derived hierarchical porous carbon electrodes with superior properties.181
Using smartphones to study vaccination decisions in the wild
No full textOne of the most important tools available to limit the spread and impact of infectious diseases is vaccination. It is therefore important to understand what factors determine people’s vaccination decisions. To this end, previous behavioural research made use of, (i) controlled but often abstract or hypothetical studies (e.g., vignettes) or, (ii) realistic but typically less flexible studies that make it difficult to understand individual decision processes (e.g., clinical trials). Combining the best of these approaches, we propose integrating real-world Bluetooth contacts via smartphones in several rounds of a game scenario, as a novel methodology to study vaccination decisions and disease spread. In our 12-week proof-of-concept study conducted with N = 494 students, we found that participants strongly responded to some of the information provided to them during or after each decision round, particularly those related to their individual health outcomes. In contrast, information related to others’ decisions and outcomes (e.g., the number of vaccinated or infected individuals) appeared to be less important. We discuss the potential of this novel method and point to fruitful areas for future research.3