bluuebunny/crossref_metadata_2025 huggingface dataset:
Quantitative 17O MRSI of myocardial oxygen metabolic rate, blood flow, and oxygen extraction fraction under normal and high workload conditions
Authors: Zhu Xiao‐Hong , Chen Wei
Published: December 2023

Purpose

The heart is a highly aerobic organ consuming most of the oxygen the body in supporting heart function. Quantitative imaging of myocardial oxygen metabolism and perfusion is essential for studying cardiac physiopathology in vivo. Here, we report a new imaging method that can simultaneously assess myocardial oxygen metabolism and blood flow in the rat heart.

Methods

This novel method is based on the 17O‐MRSI combined with brief inhalation of 17O‐isotope labeled oxygen gas for quantitative imaging of myocardial metabolic rate of oxygen consumption (MVO2), myocardial blood flow (MBF), and oxygen extraction fraction (OEF). We demonstrate this imaging method under basal and high workload conditions in rat hearts at 9.4 T.

Results

We show that this 17O MRSI–based approach can directly measure and image MVO2 (1.35–4.06 μmol/g/min), MBF (0.49–1.38 mL/g/min), and OEF (0.33–0.44) in the heart of anesthetized rat under basal and high workload (21.6 × 103–56.7 × 103 mmHg • bpm) conditions. Under high workload condition, MVO2 and MBF values in healthy rats approximately doubled, whereas OEF remained unchanged, indicating a strong coupling between myocardial oxygen metabolic demand and supply through blood perfusion.

Conclusion

The 17O‐MRSI method has been used to simultaneously image the myocardial metabolic rate of oxygen consumption, blood flow, and oxygen extraction fraction in small animal hearts, which are sensitive to the physiological changes induced by high workload. This approach could provide comprehensive measures that are critical for studying myocardial function in normal and diseased states and has a potential for translation.
Optimized quantitative mapping of cardiopulmonary oscillations using hyperpolarized 129Xe gas exchange MRI: Digital phantoms and clinical evaluation in CTEPH
Authors: Lu Junlan , Alenezi Fawaz , Bier Elianna , Leewiwatwong Suphachart , Mummy David , Kabir Sakib , Rajagopal Sudarshan , Robertson Scott , Niedbalski Peter J. , Driehuys Bastiaan
Published: December 2023

Purpose

The interaction between 129Xe atoms and pulmonary capillary red blood cells provides cardiogenic signal oscillations that display sensitivity to precapillary and postcapillary pulmonary hypertension. Recently, such oscillations have been spatially mapped, but little is known about optimal reconstruction or sensitivity to artifacts. In this study, we use digital phantom simulations to specifically optimize keyhole reconstruction for oscillation imaging. We then use this optimized method to re‐establish healthy reference values and quantitatively evaluate microvascular flow changes in patients with chronic thromboembolic pulmonary hypertension (CTEPH) before and after pulmonary thromboendarterectomy (PTE).

Methods

A six‐zone digital lung phantom was designed to investigate the effects of radial views, key radius, and SNR. One‐point Dixon 129Xe gas exchange MRI images were acquired in a healthy cohort (n = 17) to generate a reference distribution and thresholds for mapping red blood cell oscillations. These thresholds were applied to 10 CTEPH participants, with 6 rescanned following PTE.

Results

For undersampled acquisitions, a key radius of was found to optimally resolve oscillation defects while minimizing excessive heterogeneity. CTEPH participants at baseline showed higher oscillation defect + low (32 ± 14%) compared with healthy volunteers (18 ± 12%, p < 0.001). For those scanned both before and after PTE, oscillation defect + low decreased from 37 ± 13% to 23 ± 14% (p = 0.03).

Conclusions

Digital phantom simulations have informed an optimized keyhole reconstruction technique for gas exchange images acquired with standard 1‐point Dixon parameters. Our proposed methodology enables more robust quantitative mapping of cardiogenic oscillations, potentially facilitating effective regional quantification of microvascular flow impairment in patients with pulmonary vascular diseases such as CTEPH.
A double‐dynamic‐bond crosslinked multifunctional conductive hydrogel with self‐adhesive, remoldability, and rapid self‐healing properties for wearable sensing
Authors: Li Xinfeng , Zhang Tianyi , Song Baiqing , Yang Kaili , Hao Xiaoqiong , Ma Jianhua
Published: December 2023

In recent years, conductive hydrogels have been designed as flexible sensors with broad application prospects in the field of smart wearable devices. However, the coordination of the mechanical properties, self‐healing capability, and conductivity of hydrogels has always been a challenge. In this work, a multifunctional conductive hydrogel with self‐adhesive, re‐shapeable, and rapid self‐healing abilities (PB‐PACS‐PM3 (self‐healing efficiency) = 98.8% in 15 s) was prepared by incorporating protocatechualdehyde modified carboxymethyl chitosan (PA@o‐CMCS) and PDA‐modified MXene (PDA@MXene) into the interchain of polyvinyl alcohol through dynamic borate ester crosslinking. The dynamic Schiff base reaction not only effectively introduced o‐CMCS as a mechanical enhancer but also improved the viscoelasticity and self‐healing capability of the hydrogel through the dual dynamic bond crosslinking structure. The PDA@MXene nanosheets are uniformly distributed in the hydrogel, providing the composite system with excellent conductivity (the conductivity of PB‐PACS‐PM3 hydrogel is 1.5 S/m) and strain sensitivity (the response time and recovery time of the hydrogel sensor are 230 and 260 ms, respectively), while the tensile strength of the hydrogel is improved to 0.035 MPa. Due to all these advantages, this conductive hydrogel can be assembled into flexible wearable sensors for rapid and accurate monitoring of various physiological activities of the human body, such as finger, wrist, elbow, and knee bending vibrations, among others.
Hoping for a normal life: Decision‐making on hematopoietic stem cell transplantation by patients with a hemoglobinopathy and their caregivers
Authors: Mekelenkamp Hilda , de Vries Martine , Saalmink Ineke , Nur Erfan , Kerkhoffs Jean‐Louis , Heijboer Harriët , Cnossen Marjon , Lankester Arjan , Smiers Frans ,   SCORE consortium
Published: December 2023

Background

To provide insight into the perspectives of children and young adults with transfusion‐dependent thalassemia and sickle cell disease and their caregivers regarding the decision for hematopoietic stem cell transplantation (HSCT).

Procedure

A qualitative longitudinal multicenter study. Data collection consisted of 40 audio‐recorded conversations between physicians and families and 77 interviews with patients and/or caregivers related to 27 unique cases, collected at different time points throughout the decision‐making process.

Results

Conversations and interviews revealed “hoping for a normal life” as an overarching theme, consisting of four main topics: (i) “Building a frame of reference” refers to a process where patients or families try to obtain comprehensive information on HSCT and translate this to their situation to decide. (ii) “Balancing between loss and benefit” reports the process of considering the advantages and disadvantages of continuing with supportive care to treat their disease versus choosing HSCT. (iii) “Experiencing the impact of HSCT” describes the impactfull experience of the HSCT period by those who chose HSCT. (iv) “Balancing again” refers to reflecting on the decision made.

Conclusions

The hope for a normal life guided the decision‐making process, described as a constant balance between the impact of the disease and HSCT. A structured approach to explore patients’ and caregivers’ perspectives on HSCT decision‐making is needed, where specifically discussing the impact of the disease and hope for a normal life need to be integrated in the process.
Thermal aging effect on mechanical properties of polyamide 6 matrix composites produced by TFP and compression molding
Authors: Yarar Eser , Şahin Alp Eren , Kara Hasan , Çep Emine Baş , Bora Mustafa Özgür
Published: December 2023

Tailored Fiber Placement is an innovative manufacturing technique that precisely positions continuous fibers in critical areas of fiber preforms for optimal structural performance. This study focuses on producing glass fiber‐reinforced polyamide composites using TFP technology and compression molding to address the durability concerns of thermoplastic matrix composites in automotive parts. The production process involved a constant temperature of 300°C, 16 bar pressure, and holding times of 270, 300, and 330 s. Short‐term thermal aging cycles were applied to simulate automotive part acclimatization. Tensile and 3‐point bending tests were conducted to evaluate mechanical properties. Statistical analysis using response surface methodology provided insights into the relationship between production parameters and mechanical properties. Differential Scanning Calorimetry characterized the composite material, and macroscopic damage analysis was performed. Results showed a potential 10% decrease in tensile strength due to short‐term thermal aging. Aging had the most significant impact on elastic modulus and tensile strength according to the Pareto chart. Flexural modulus increased, while flexural strength decreased with thermal aging. Holding time had no effect on flexural modulus but reduced flexural strength.

Highlights

Glass/polyamide composites were produced by compression molding with TFP technology.

Short‐term thermal aging cycles were applied on the GF‐PA6 composite material.

Mechanical properties were analyzed statistically according to the RSM.

TFP technique can assist OEM companies in lowering desired target cost per vehicle.
Enhancing ablation and oxidation resistance of phenolic resin with modified pickling asbestos
Authors: Shi Jun‐Feng , Li Nan , Zhang Feng , Gao Jie‐Feng , Wang Yue‐Yi , Yan Ding‐Xiang
Published: December 2023

Given the increasing requirements for ablative thermal protection materials, there is an urgent need for boron phenolic resin (BPR) composites with excellent high‐temperature strength properties as well as ablation performance to address the structural failure during the ablation process of these devices. Herein, modified pickling asbestos (MPA) was successfully incorporated into BPR to prepare MPA‐modified BPR (MPABPR). In addition, one‐dimensional MPA with improved dispersion and compatibility was used to fabricate a fiber‐reinforced network inside of BPR for the first time, which effectively increased the high‐temperature strength and ablation resistance of BPR. The results demonstrated that the high‐temperature strength of MPABPR was optimally improved by 25% compared to pure BPR. Meanwhile, when the content of MPA was only 5 wt%, the linear and mass ablation rates of MPABPR could reduce to 0.046 mm/s and 0.043 g/s, which were 34.3% and 23.2% lower than that of pure BPR, respectively. This study has the enormous potential to provide a new strategy for preparing high‐performance BPR matrix materials.

Highlights

The dispersion and compatibility of PA are improved by modification.

MPA constructs a fiber‐reinforced network that can strengthen the carbon layer.

The ablative properties of MPABPR have great advantages over the BPR.

The compressive strength of carbonized MPABPR5 is 25% higher than that of BPR.
Epoxy resin with both ultraviolet shielding and enhanced thermal mechanical properties: Study on synergistic modification of Ce–Zr–Si oxide nanoparticles and basalt fibers
Authors: Li Yi , Zhang Ning , Liang Jicai , Yu Kaifeng , Zhao Zengxia , Liang Ce
Published: December 2023

Composites with good thermomechanical and UV‐shielding properties are essential in fiber‐reinforced composites. This paper focuses on composites' ultraviolet (UV) shielding efficiency with added Ce‐Zr‐Si oxide nanoparticles/epoxy resin. The Ce‐Zr oxide nanoparticles were first functionalized with a silicon coupling agent and ethyl silicate to improve their dispersion and surface activity. In this work, we prepared epoxy nanocomposites with the addition of Ce‐Zr ‐Si oxides(1,3,5,7 wt%) and found that the materials had good enhancement of the UV shielding properties of the epoxy resin matrix. Meanwhile, it was used in basalt fiber (BF)/epoxy composites prepared by the hot‐pressing method, and surface treatment of basalt fibers was carried out. The results showed that the modified fiber composites could effectively enhance the thermomechanical properties of epoxy resin composites. It is noteworthy that the tensile strength and flexural strength of the hybrid composites reached their peak when 5 wt% Ce‐Zr‐Si was added, increasing by 13.8% and 33.67% respectively. The modified (BF)/epoxy composites exhibited improved thermal stability compared to pure epoxy resin, with the maximum weight loss temperature of BF‐1/EP reaching 349°C. The T(UVA) decreased to 2.41%, while the T(UVB) decreased to 0.053%, and almost all the ultraviolet irradiation was blocked. These results show that our prepared composites have good thermomechanical and UV shielding properties.

Highlights

Ce‐Zr oxide nanoparticles were functionalized with a silicon coupling agent.

Ce‐Zr‐Si oxide was added to enhance the ultraviolet shielding efficiency.

Modified BFs were composited to improve thermomechanical properties.
In‐plane and in‐depth frontal polymerization behaviors of continuous fiber‐reinforced epoxy composites
Authors: Luo Tingting , Fu Kunkun , Zhu Huixin , Chen Yuan , Yang Bin , Li Yan
Published: December 2023

Frontal polymerization (FP) is a self‐sustaining reaction that relies on polymerization exothermicity and heat transfer. This study explores the in‐plane and in‐depth FP mechanisms of continuous fiber‐reinforced epoxy composites. First, the effects of initiator and diluent concentrations on the FP behaviors of neat epoxy resins were examined. It was found that the frontal velocity and frontal temperature of the neat resins increase with an increase of either the initiator concentration or the diluent content, depending on the polymerization enthalpy and curing kinetics. Then, the FP behaviors of continuous carbon fiber and glass fiber‐reinforced epoxy woven composites were investigated. The results showed that the in‐plane FP behavior of the composites was primarily controlled by the thermal conductivity and specific heat capacity of the continuous fibers, whereas the in‐depth FP behavior mainly depended on the pores of the woven fabrics.

Highlights

Frontal velocity and temperature of neat resins are controlled by the polymerization enthalpy and curing kinetics.

The in‐plane FP behavior of continuous fiber reinforced composites is dependent on the thermal conductivity and specific heat capacity of the fibers.

The in‐depth FP behavior of composite is determined by both the thermal conductivity of fibers and the pores of fabrics.
Neonatal hepatitis B vaccination: Reevaluating timing and adjuvants for enhanced safety and effectiveness
Authors: Cirovic Aleksandar , Cirovic Ana , Ivanovski Ana , Ivanovski Petar
Published: December 2023

Our aim is an achievement of a 100 percent vaccination rate without toxic vaccine effects. We did a comprehensive literature review on aluminum neurotoxicity and early neonatal hepatitis B vaccination. We analyzed indications for introduction of early neonatal hepatitis B vaccination and the data on experimental and clinical aluminum‐induced neurotoxicity. It is justified very early hepatitis B vaccination to be carried out in high‐risk endemic areas. In those countries there is a large number of hepatitis B positive individuals, including pregnant women, which leads to a great number of vertical, mother‐to‐child, transmissions of the virus during pregnancy. There is also a serious risk of perinatal Hepatitis B virus infections in such countries. Early neonatal hepatitis B vaccination is also carried out in low‐risk countries, where the number of hepatitis B positive pregnant women is extremely small, making the number of newborns who require the prevention of hepatitis B infection extremely small as well. It is necessary for all vaccines which contain aluminum as an adjuvant to be immediately suspended as children vaccination until they start walking and until aluminum is replaced with calcium, zinc or a nonmetallic adjuvant such as microcrystalline tyrosine or monosodium urate. Meanwhile sustained efforts should be made to create the so‐called mucosal vaccines against diphtheria, pertussis, measles, mumps and rubella. At the same time, all the children born to hepatitis B positive mothers, regardless of their place of birth must be vaccinated against hepatitis B as the benefits from vaccines by far outweigh potential harm caused by adjuvant aluminum.
Concentration effect on the chain structure and photoelectric properties of conjugated polymer precursor solutions and thin films: A mini review
Authors: Zhang Yuhua , Cheng Dongyang , Li Tao , Guan Yijia , Liu Bin , Zhang Hao , Lu Dan
Published: December 2023

Conjugated polymers have attracted extensive attention in numerous research fields because of their exceptional photoelectric properties and distinctive solution processing capabilities. The conformation of the chain and the structure of the condensed state in solution are closely related to various factors, such as concentration and solvent. Concentration, as a significant external parameter, plays a crucial role in the self‐assembly and formation of crystalline structures in conjugated polymers. It also affects the properties of the solution, the structure of the membrane, and the performance of the fabricated devices. Recently, there have been an increasing number of studies conducted from the perspective of solution concentration. Therefore, it is important to comprehensively summarize the effect of concentration on the transition process of chain structure from solution to film, as well as the impact of concentration on the performance of related devices. In this review, we summarize the effects of concentration on the chain motion, particle size, ordered structure, and photoelectric properties of conjugated polymers in solutions and thin films, as well as on device efficiency. This provides a unique perspective on the fundamental characteristics of conjugated polymers, which can assist in the development and improvement of optoelectronic devices.
Aerobic Synthesis and Nucleophilicity of 2,3‐Dihydroindolizines
Authors: Qiu Dong , Su Yijin
Published: December 2023

Herein, we reported a practical and metal‐free synthesis of 2,3‐dihydroindolizines using N‐alkyl pyridinium salts and electron‐deficient alkenes with ambient air as a sole oxidant. Interestingly, a halogen bond donor (penta‐fluoroiodobenzene 20 mol %) was successfully applied to promote this partial oxidation by slowing down the undesired decomposition processes, probably because of the formation of a halogen‐bonded adduct. Moreover, the C1 position of 2,3‐dihydroindolizines was utilized as a good nucleophile for nucleophilic aromatic substitution with 4‐iodo‐1‐methylpyridin‐1‐ium trifluoromethanesulfonate as electrophile and provided a new‐type dipyridinium compound effectively.
Beyond the finish line: How losing in patent race drives post‐race innovation
Authors: Hong A‐Sung
Published: December 2023

Research Summary

Although patent races of leading technology firms have garnered significant attention in the prior literature, it remains unclear how the outcome of a patent race affects subsequent firm‐level innovation. Drawing on agency theory, we propose that losing a patent race drives firms to pursue more technological innovation than winning due to managerial concerns. To investigate the mechanism, we hypothesize that the positive impact of a lost race on a firm's innovation is more pronounced when more shareholders hold near‐term investment horizons and when a CEO is less protected against the pressure of shareholders. By constructing a unique dataset of simultaneous patent applications, we find evidence consistent with the proposed theory.

Managerial Summary

This study explores the impact of a patent race on the subsequent innovation of leading technology firms. We find that losing firms tend to pursue more innovation after the race, surpassing the winner in terms of innovation. This finding is particularly pronounced when top managers are more pressured by the shareholders. Specifically, we show that the positive effect of a lost race is especially evident in publicly listed companies with a higher ratio of short‐term institutional investors and where CEOs have less protection from shareholder pressures in the public market. This research underscores how a setback in a technology competition can act as a catalyst to change innovation dynamics among competitors at the technology frontiers.
Design of Novel Photoactive Modified Titanium Silicalites and Their Application for Venlafaxine Degradation under Simulated Solar Irradiation
Authors: Cruz‐Quesada Guillermo , Sampaio Maria J. , Espinal‐Viguri Maialen , López‐Ramón María Victoria , Garrido Julián J. , Silva Cláudia G. , Faria Joaquim L.
Published: December 2023

Titanium silicalites (TS) are well‐known materials for their use in industrial oxidation reactions, and although they are used as photocatalysts, their activity is limited. Therefore, numerous synthetic strategies are investigated to improve their photocatalytic activity. Herein, three series of modified titanium silicalites are synthesized using three different organotriethoxysilanes at different molar percentages with the aim of modifying the structure of the zeolite, both at a porous and chemical level, to obtain materials with high photocatalytic activity. The study of their morphological, textural, chemical, and UV–vis light absorption properties through various characterization techniques has allowed the selection of the best candidates to test their photoactivity in the degradation of venlafaxine, an antidepressant drug that persists as a contaminant in wastewater and has serious neurotoxic effects. Materials synthesized using a 5% molar percentage of RTEOS and 10% of PhTEOS (Ph = phenyl) are able to degrade venlafaxine, whereas the reference material does not show any photocatalytic activity. These results lead the way to use this synthetic strategy to develop titanium silicates and optimize their photocatalytic activity in degradation reactions of different pollutants.
Ball milling‐assisted exfoliation and deposition to prepare few‐layer graphene/PVC nanocomposites with enhanced thermal stability
Authors: Li Jinyun , Xu Jingwei , Chen Wenhua , Ma Chen , Chen Guohua
Published: December 2023

It is still a great challenge to prepare high‐performance graphene/polymer nanocomposites by fully utilizing the large surface area, high tensile strength, and high thermal stability. Herein, a simple but efficient approach based on ball milling was developed to in situ exfoliate graphite into single‐layer graphene and simultaneously deposit them onto polyvinyl chloride (PVC) surface. Graphene/PVC nanocomposites were prepared via the plasticized molding and followed by hot pressing. Resulting from incorporation of highly exfoliated and evenly distributed graphene nanosheets, the obtained graphene/PVC nanocomposites displayed a significantly enhanced thermal stability. In contrast with neat PVC, the temperature of maximum weight loss (Tmax), glass transition temperature (Tg), and residual content of composite with 2.0 wt% graphene were increased by 10, 13°C, and 4.4%, respectively. Based on the deep analysis on heat releasing behavior and structure of residue, we proposed the related enhancing mechanism. Large‐area and highly exfoliated graphene sheets effectively inhibited the heat/mass transfer in composite system and prevented the degradation of PVC, as well as promoted the compact residue formation from polymer itself at high temperatures. In short, this work provided an environmentally friendly strategy to prepare high‐performance graphene/polymer nanocomposites with using low additive amount of single‐layer graphene.

Highlights

A simple graphite exfoliation method based on ball milling was proposed.

Strong shearing and compact force induce graphene exfoliation and deposition.

Graphene/PVC nanocomposites with enhanced thermal stability was prepared.
Pathology and forensic science: Dignity, respect, and the dead body
Authors: Jones Imogen
Published: December 2023

This perspective considers the forensic examination of deceased bodies via the medico‐legal autopsy. It is argued that the decisions we make about what we do with, and to, deceased bodies and body parts is, and should be, limited by the need to treat bodies with dignity and respect. The treatment of parts of bodies has been explored in bioethics, substantially due to organ retention scandals bringing this to the public and political attention. But these cases—although important—represent extremes. This perspective therefore focuses on routine death investigations and the extent to which scientific method should be limited because of the competing interests in the deceased body and its treatment. It is argued that how we treat bodies/body parts matters because they represent once‐living people with contexts, histories, and relationships. They had, and perhaps still have, value as human persons. As humans, we share complex relationships and have different views and interpretations of what our duties are to each other. Dignity and respect aid by providing baseline standards, and are reflected as such in professional codes and regulations. However, the system is imbued with sufficient discretion that it is impossible to achieve consistency of standards or practice. This means that the treatment of deceased bodies in forensic science will differ substantially depending on both context and the practitioners involved.

This article is categorized under:

Forensic Medicine > Medicolegal Death Investigation Systems
Alles unter einem Dach? Einstellungen und erforderliche Kompetenzen für die erfolgreiche Nutzung von BIM-orientierten digitalen Technologien in KMU am Beispiel von Koop-3D
Authors: Tartler Darien , Rothenbusch Sandra , Kauffeld Simone
Published: December 2023

Im Zuge der Digitalisierung verschmilzt die reale Arbeitswelt auch im Handwerk zunehmend mit der virtuellen. Die Einführung digitaler Technologien am Arbeitsplatz geht dabei mit Herausforderungen einher. Mitarbeitende in kleinen und mittleren Unternehmen (KMU) benötigen neue Kompetenzen für eine effektive Nutzung digitaler Technologien. Dafür sollten KMU gemäß der soziotechnischen Systemtheorie die Einführung durch die gezielte Förderung von Kompetenzen und Technikakzeptanz begleiten. Diese Studie soll dafür am Beispiel von Koop-3D, einem digitalen Gebäudemodellierungstool zum Planungs- und Ausführungsmanagement in der gewerkeübergreifenden Kooperation im Baugewerbe, folgende Forschungsfragen beantworten: Welche Gewerkevertretende würden Koop-3D in der Praxis aus welchen Gründen (nicht) einsetzen? Welche Chancen und Risiken sehen die Gewerkevertretenden durch Koop-3D für die Kooperation? Welche Methoden-, Sozial-, Fach und Selbstkompetenzen werden zur Nutzung von Koop-3D benötigt? Zur Überprüfung dieser Fragestellungen wurde Fachpersonen aus dem Baugewerbe eine Videovignette vorgelegt und via Fragebogen evaluiert. Es werden Chancen und Risiken von, sowie notwendige Kompetenzen für die Nutzung von Koop-3D in KMU identifiziert. Basierend auf diesen Ergebnissen werden konkrete Handlungsempfehlungen abgeleitet, die KMU im Baugewerbe bei der Einführung neuer digitaler Technologien unterstützen sollen.
Management wirksamer agiler Lernprozesse mithilfe digitalisierter Personaleinsatzplanung in KMUs
Authors: Mynarek Felix , Jahr Michael
Published: December 2023

Unternehmen und größere Organisationen stehen in sich schnell wandelnden Märkten und bei komplexen Umweltbedingungen vor immer neuen und teilweise schwer abschätzbaren Herausforderungen, deren Bewältigung einen nachhaltig nutzbaren (Kern-)Kompetenzerwerb verlangt. Kontinuierliches Lernen und insbesondere informelles Lernen sind hierfür entscheidende Bausteine. Diese informellen Lerngelegenheiten, die vor allem durch den gemeinsamen Austausch und die individuelle Reflexion gekennzeichnet sind, sollten daher bereits bei der Planung von operativen Arbeitsabläufen und Projekten systematisch berücksichtigt werden. Allerdings ist die Planung von Arbeitsreihenfolgen mit vielen und knappen Ressourcen vor allem bei Mehrfachzielsetzung ein komplexes Problem. So sollten für eine digitalisierte Planung leistungsstarke Methoden aus dem Bereich Künstlicher Intelligenz (KI) eingesetzt werden, um ein optimales Ergebnis erzielen zu können. Mithilfe entsprechender smarter Algorithmik wird gezeigt, wie Agile Lernprozesse, z. B. selbstorganisierbare Austausche, zielgerecht in automatisch berechnete dynamische Zeitfenster in einen Arbeits- und Projektplan integriert werden können. In der Folge eröffnet sich für Unternehmen die Möglichkeit zusätzlich zu der bisherigen Nutzung formaler Lerneinheiten ebenso informelles Lernen zu systematisieren bzw. die hierfür erforderlichen Rahmenbedingungen im operativen Tagesgeschäft zu schaffen.
How to awaken a sleeping giant: antagonistic expression of Flowering locus T homologs and elements of the age-related pathway are associated with the flowering transition in Agave tequilana
Authors: Hernández-Soriano Laura , Gálvez-Sandre Laura , Ávila de Dios Emmanuel , Simpson June
Published: December 2023

Key message

Antagonistic expression of Flowering locus T proteins and the ageing pathway via miRNAs and sugar metabolism regulate the initiation of flowering in A. tequilana.

Flowering in commercial plantations of Agave tequilana signals that plants are ready to harvest for tequila production. However, time of flowering is often unpredictable and a detailed understanding of the process would be beneficial in the field, for breeding and for the development of future research. This report describes the functional analysis of A. tequilana FLOWERING LOCUS T (FT) genes by heterologous expression in A. thaliana and in situ hybridization in agave plants. The gene structures of the Agave tequilana FT family are also described and putative regulatory promoter elements were identified. Most Agave species have monocarpic, perennial life cycles that can last over 25 years during which plants do not respond to the normal environmental signals which induce flowering, suggesting that the ageing pathway as described in Arabidopsis may play an important role in determining flowering time in these species. Elements of this pathway were analyzed and in silico data is presented that supports the regulation of SQUAMOSA PROMOTER BINDING LIKE proteins (SPL), APETALA2 (AP2) proteins and members of Plant Glycoside Hydrolase Family 32 (PGHF32) by interactions with miRNAs 156, 172 and 164 during the initiation of flowering in A. tequilana.
Direct calculation of the equilibrium composition for multi-component Langmuir isotherms in batch adsorption
Authors: Kaiblinger Norbert , Hahn Rainer , Beck Jürgen , Wang Yiran , Carta Giorgio
Published: December 2023

The extended Langmuir isotherm is commonly used to describe multi-component adsorption. In batch adsorption, the equilibrium composition can be computed by solving simultaneously the Langmuir equations and the material balance equations numerically. We demonstrate that for given values of the initial fluid-phase concentrations, the adsorbed phase composition of all components can be expressed in terms of the fluid-phase concentration of a reference species. As a result, the adsorbed phase composition is easily derived by combining the isotherm expression for the reference species with the corresponding material balance. We derive a general graphical representation of the underlying mathematics valid for N components along with the analytic solution for two-component systems.
Quipu Quivers and Nakayama Algebras with Almost Separate Relations
Authors: Fosse Didrik
Published: December 2023

A Nakayama algebra with almost separate relations is one where the overlap between any pair of relations is at most one arrow. In this paper we give a derived equivalence between such Nakayama algebras and path algebras of quivers of a special form known as quipu quivers. Furthermore, we show how this derived equivalence can be used to produce a complete classification of linear Nakayama algebras with almost separate relations. As an application, we include a list of the derived equivalence classes of all Nakayama algebras of length $$\le 8$$

≤
8

with almost separate relations.
LncRNA HCP5 Facilitates the Progression of Ovarian Cancer by Interacting with the PTBP1 Protein
Authors: Shou Jian , Zhang Chuanling , Zheng Xiaoyu , Li Yaowei , Wu Peng , Chen Long , Wei XiuJun
Published: December 2023

Ovarian cancer (OC) is a major gynecological malignancy with an annually increasing morbidity that poses a significant threat to the health of women worldwide. Most OC patients are diagnosed at an advanced stage. It is an urgent task to search for biomarkers for the diagnosis and treatment of OC. The lncRNA HCP5 (HCP5) was recently identified as an oncogene in several malignant tumors. However, the function of HCP5 in OC has rarely been reported. Herein, the levels of HCP5 and PTBP1 were found to be markedly increased in malignant OC tumor tissues and OC cell lines. In HCP5-silenced SKOV-3 and HEY cells, cell viability was markedly decreased, and the apoptosis rate was significantly increased, with more cells exhibiting G0/G1 arrest and increased expression of cleaved caspase-3 and cleaved caspase-9. Furthermore, the number of migrated cells, number of invaded cells, and migration distance were notably decreased by the knockdown of HCP5 in SKOV-3 cells and HEY cells. In the xenograft model established with SKOV-3 cells, the number of lung metastases, tumor growth, and Ki67 expression in tumor tissues were markedly decreased by the knockdown of HCP5, accompanied by an increased percentage of TUNEL-positive cells. HCP5 was found to be localized in the nucleus, and the interaction between HCP5 and PTBP1 was verified by RNA pull-down and RNA immunoprecipitation assays. Furthermore, in HCP5-overexpressing OC cells, the impacts of HCP5 on cell proliferation and apoptosis were significantly attenuated by the knockdown of PTBP1. Collectively, these results indicate that HCP5 facilitates the progression of OC by interacting with the PTBP1 protein.
Success factors for effective plastic avoidance in tourism: a German consumer study with focus on beach holidays
Authors: Friedrich Daniel
Published: December 2023

Hotels are under increasing pressure to reduce their plastic consumption and keep holiday destinations cleaner. Tourism experts already pointed to a variety of solutions, from replacing, avoiding to waste collection campaigns with guests. This study mirrors these measures with the opinions of German consumers who, in the European Union, travel most and mainly for beach holiday. A survey (n = 630) showed that plastic prevention should be practised by holiday organisers, actively involving guests, e.g. in beach clean-ups, was least popular. Personal attitudes towards plastic avoidance had no effect, but rather women and older people were more willing to engage on holiday (max. r = 0.17). Also, agreement tended to decrease with the distance of the holiday destination (max. r = 0.11). For effective marketing, providers of plastic-free holidays should rather avoid this material than replacing it and participate in environmental protection projects on destinations and get certified for this. This most convinces diverse consumer groups, instead of demonstrating sustainability with obligations and bans.
Visual Education and the Care of the Figuring Self. Mr. Palomar’s Exercises as Pedagogy
Authors: Oliverio Stefano
Published: December 2023

This paper engages with Italo Calvino’s lecture on Visibility, included in his last—and testamentary—volume Six Memos, by understanding it in an educational and pedagogical key. While the question of pedagogy is expressly addressed by Calvino himself in his lecture, the interpretation here provided is not merely an application of his tenets but an elaboration on and an autonomous development of them. In particular, in the spotlight there is the intimate bond image-cum-writing which seems to preside over Calvino’s insights and is here suggested as key to tackling the challenges of the contemporary mediascape and the “tautological vision” dominating therein. While a part of the educational discourse invokes “homeostatic” pedagogical solutions, namely the (ultimately confrontational) deployment of writing to compensate for the iconic ruling regime, this paper explores the possibility of a specific kind of visual education (instantiated by comics and Otto Neurath’s Isotype), which combines the role of the image with some features traditionally attributed to the pedagogy of writing (e.g. the cultivation of abilities of abstraction, of reflection etc.). A pedagogy of figuration is, accordingly, proposed as an interruption of the tautological vision of the new media and as conducive to educating readers of the unwritten world and of the world of digital images, Mr. Palomar—the hero of Calvino’s last novel—possibly being the archetype of this kind of (new?) readership. By referring to two influential notions in the contemporary debate in educational philosophy and theory, this pedagogy is finally interpreted in term of (visual) thing-centredness rather than (visual) subjectification.
Survivability and proliferation of microorganisms in bentonite with implication to radioactive waste geological disposal: strong effect of temperature and negligible effect of pressure
Authors: Bartak Deepa , Bedrníková Eva , Kašpar Vlastislav , Říha Jakub , Hlaváčková Veronika , Večerník Petr , Šachlová Šárka , Černá Kateřina
Published: December 2023

As bentonite hosts a diverse spectrum of indigenous microorganisms with the potential to influence the long-term stability of deep geological repositories, it is essential to understand the factors influencing microbial activity under repository conditions. Here, we focus on two factors, i.e., temperature and swelling pressure, using a suspension of Cerny Vrch bentonite to boost microbial activity and evaluate microbial response. Suspensions were exposed either to different pressures (10, 12 and 15 MPa; to simulate the effect of swelling pressure) or elevated temperatures (60, 70, 80 and 90 °C; to simulate the effect of cannister heating) for four weeks. Each treatment was followed by a period of anaerobic incubation at atmospheric pressure/laboratory temperature to assess microbial recovery after treatment. Microbial load and community structure were then estimated using molecular-genetic methods, with presence of living cells confirmed through microscopic analysis. Our study demonstrated that discrete application of pressure did not influence on overall microbial activity or proliferation, implying that pressure evolution during bentonite swelling is not the critical factor responsible for microbial suppression in saturated bentonites. However, pressure treatment caused significant shifts in microbial community structure. We also demonstrated that microbial activity decreased with increasing temperature, and that heat treatment strongly influenced bentonite microbial community structure, with several thermophilic taxa identified. A temperature of 90 °C proved to be limiting for microbial activity and proliferation in all bentonite suspensions. Our study emphasizes the crucial role of a deep understanding of microbial activity under repository-relevant conditions in identifying possible strategies to mitigate the microbial potential within the deep geological repository and increase its long-term stability and safety.
Ti-Fe Phase Evolution and Equilibria Toward β-Ti Superalloys
Authors: O’Kelly P. , Watson A. , Schmidt G. , Galetz M. , Knowles A. J.
Published: December 2023

Recent design and development of precipitate reinforced refractory metal alloys demonstrate the possibility of A2 + B2 bcc superalloys as a new class of high temperature materials. Existing β-Ti alloys do not typically employ reinforcement with intermetallics, as in other high temperature alloys; to this effect sufficient additions of Fe, a low cost β-Ti stabiliser, can promote formation of an ordered-bcc intermetallic phase, β′-TiFe (B2), offering scope to develop a β + β′ dual-phase field. However, key uncertainties exist in the base Ti-Fe binary. The current research evaluates the formation of ordered-bcc TiFe precipitates within a disordered-bcc β-Ti matrix through variable heat treatment strategies. The microstructure optimisation has revealed new insight into the Ti-Fe phase equilibria at near eutectoid temperatures in the purported dual-phase field, where a complex interplay between β-Ti, β′-TiFe and α-Ti exists.
Methodological comparison of laser stripping solutions with contemporary pulsed lasers for e-drive copper hairpins
Authors: D’Arcangelo Simone , Caprio Leonardo , Chesi Davide , Nocciolini Daniele , Corbinelli Rubino , Previtali Barbara , Demir Ali Gökhan
Published: December 2023

The electric drives used in traction applications employ conventionally pure Cu bars bent to the required form, inserted in the stator and welded by a laser at the extremities. These extremities, which are referred to as Cu hairpins, should be stripped off from the electrically isolating polymeric enamel. Laser stripping is industrially used to remove the enamel from the Cu surface. Pulsed wave lasers are employed for the purpose with a large variety of solutions industrially available to the end users. The peculiar process may give way to material removal by surface heating for instance using infrared radiation (IR) or ultraviolet (UV) lasers or an indirect material expulsion via near-infrared (NIR) sources. Accordingly all major laser sources, namely CO2, active fiber, active disk, and Nd:YAG at different wavelengths, may be used for the purpose. Such laser sources possess very different characteristics regarding the pulse durations, power levels, and beam diameters. As newer laser system solutions are made available, the need for methods and experimental procedures to compare the process performance also increases. This work compares 7 different hairpin stripping solutions based on contemporary pulsed laser sources along with a detailed comparative analysis method. Initially, the 7 laser sources are used for hairpin stripping. The process quality is analyzed through surface morphology, chemistry, and the mechanical strength upon laser welding. Productivity and efficiency indicators are collected. Using the collected data, the work proposes system configurations for three different scenarios prioritizing quality, productivity, and cost.
A method for an efficiency and weight-optimised preliminary design of a hydrogen-powered fuel cell-based hybrid-electric propulsion system for aviation purposes
Authors: Akkaya Mücahit , Neumann Nicolai , Peitsch Dieter
Published: December 2023

There is a worldwide effort to advance the usage of zero-emission propulsion systems for aircraft. Due to their high thermodynamic efficiency and the fact that they produce no $$\textrm{CO}_{2}$$

CO
2

and $$\textrm{NO}_{x}$$

NO
x

emissions, hydrogen-powered fuel cells are becoming increasingly popular for aviation purposes. However, fuel cell systems suffer from lower power density and higher cooling requirements when compared to conventional propulsion systems. Harnessing the high potential requires an optimised design of the whole propulsion system and its heat management system. This paper aims to present a method for the preliminary design and dimensioning of a fuel cell-based hybrid-electric propulsion system, which respects the limits of the heat management system and is weight and efficiency optimised. Thermodynamic models of the whole propulsion system are a crucial element to enable further investigations. Such a model has been developed, which is suitable for unsteady simulations of the propulsion and the heat management system performance of a short-range four-seater aircraft. A parameter study of the design parameters has been performed to display their impact on the system mass, the overall efficiency and the total hydrogen consumption. These results enable the identification of an overall optimised configuration. The study indicates that fuel cell-only configurations with an oversized fuel cell stack are beneficial for the analysed aircraft and flight mission.
Algorithmic Fairness, Risk, and the Dominant Protective Agency
Authors: Franke Ulrik
Published: December 2023

With increasing use of automated algorithmic decision-making, issues of algorithmic fairness have attracted much attention lately. In this growing literature, existing concepts from ethics and political philosophy are often applied to new contexts. The reverse—that novel insights from the algorithmic fairness literature are fed back into ethics and political philosophy—is far less established. However, this short commentary on Baumann and Loi (Philosophy & Technology, 36(3), 45 2023) aims to do precisely this. Baumann and Loi argue that among algorithmic group fairness measures proposed, one—sufficiency (well-calibration) is morally defensible for insurers to use, whereas independence (statistical parity or demographic parity) and separation (equalized odds) are not normatively appropriate in the insurance context. Such a result may seem to be of relatively narrow interest to insurers and insurance scholars only. We argue, however, that arguments such as that offered by Baumann and Loi have an important but so far overlooked connection to the derivation of the minimal state offered by Nozick (1974) and thus to political philosophy at large.
Influence of nitrogen-doped shielding gas for welding of medium manganese austenites for cryogenic applications
Authors: Neef Philipp , Reppin Christoph , Treutler Kai , Gericke Andreas , Henkel Knuth-Michael , Wesling Volker
Published: December 2023

The relevance of technical gases is constantly increasing due to environmental and climate policy requirements. The storage and transport of liquefied natural gas (LNG) takes place under cryogenic conditions with substantial volume reduction due to significant storage efficiency. Consequently, there are specific requirements for the mechanical properties of the applied materials at cryogenic temperatures. The materials used so far have been cold-hard, high-nickel austenites, and martensitic steels of the X8Ni9 type. The austenitic materials offer good processing properties, but due to their comparatively low strength and high costs, these materials are not attractive. In contrast, the welding of the martensite has a significant negative impact on the processing quality and the automation of the process. In order to address the problems of automation, material costs, and mechanical properties, particularly high strength and cold toughness, the application of innovative austenitic steels with a medium as well as a high manganese content is suggested. For the qualification of medium manganese austenites as a substitute for maritime applications, the welding processing of an X2CrMnNiN17-7–5 (1.4371) is considered under the aspects of the standards and guidelines of the International Association of Classification Societies (IACS), the International Maritime Organization (IMO) and the classification society Det Norske Veritas (DNV). Preliminary investigations have revealed that the application of a conventional filler metal of type G 20 16 3 Mn N L in combination with nitrogen doping of the M12-ArC-2.5 shielding gas according to DIN EN ISO 14175 results in a significant enhancement of the mechanical properties. The addition of 4% nitrogen into the shielding gas caused a diffusion-induced increase in the nitrogen content of the weld metal and a simultaneous increase in strength. Additionally, there were no negative influences on the austenitic microstructure. In consideration of the qualification specifications for welded joints and filler metals of the standards and guidelines according to IACS, IMO, and DNV, the joint welds are examined, and the qualification of the welding process is envisaged. For this purpose, comparative welds of the mentioned material combination are carried out and compared with both the initial gas mixtures and the nitrogen-doped shielding gas.