bluuebunny/crossref_metadata_2025 huggingface dataset:
Impact of clod (aggregate) size on evaporation rate and soil moisture profile during the drying process
Authors: Matsumoto Yoshihiro , Yoshida Shuichiro , Okabe Akimasa , Nishida Kazuhiro
Published: September 2023

Large clods (centimetres in size) can be formed by tillage in clayey paddy fields where upland crops are planted. These clods cause early water depletion near the soil surface, which decreases crop germination and emergence rates. Because of the difficulty in reducing clod size, desiccation damage to seeds can be avoided by adjusting the seeding depth based on the clod size‐dependent soil moisture profile. This study aimed to clarify the effect of clod size on (1) the evaporation rate (E) and soil moisture profile and (2) the mobility of soil water during the drying process. Evaporation experiments were conducted in an air‐conditioned greenhouse with natural light using cylindrical columns filled with artificially made clods 3 (L columns) and 1 cm (S columns) in diameter. We measured E, potential evaporation rate (PE), and total soil moisture content (wtot) throughout the experiment and the soil moisture profiles at the end of the experiment. The water diffusivity (Dw) and apparent vapour diffusion coefficient (dvap) were calculated as the mobility of soil water and water vapour, respectively. We found that wtot was lower in the L column than in the S column, although not at the onset of the experiment. At the end of the experiment, the soil moisture content was lower in the L column than in the S column throughout the soil layer. In contrast, E/PE was higher in the L column than in the S column throughout the experiment and even at the same wtot. Regarding mobility, Dw was slightly greater in the L column than in the S column in the soil moisture content range, where vapour movement could be greater than liquid water movement. In addition, the ratio of dvap to the diffusion coefficient of water vapour in soil was higher than unity in both columns and was 2.4–3.2 times higher in the L column than in the S column. In summary, larger clods caused a higher evaporation rate and lower soil moisture content, owing to the increased enhancement of water vapour movement probably induced by wind.
Environmental modulation of plant mycorrhizal traits in the global flora
Authors: Meng Yiming , Davison John , Clarke John T. , Zobel Martin , Gerz Maret , Moora Mari , Öpik Maarja , Bueno C. Guillermo
Published: September 2023

Mycorrhizal symbioses are known to strongly influence plant performance, structure plant communities and shape ecosystem dynamics. Plant mycorrhizal traits, such as those characterising mycorrhizal type (arbuscular (AM), ecto‐, ericoid or orchid mycorrhiza) and status (obligately (OM), facultatively (FM) or non‐mycorrhizal) offer valuable insight into plant belowground functionality. Here, we compile available plant mycorrhizal trait information and global occurrence data (100 million records) for 11,770 vascular plant species. Using a plant phylogenetic mega‐tree and high‐resolution climatic and edaphic data layers, we assess phylogenetic and environmental correlates of plant mycorrhizal traits. We find that plant mycorrhizal type is more phylogenetically conserved than plant mycorrhizal status, while environmental variables (both climatic and edaphic; notably soil texture) explain more variation in mycorrhizal status, especially FM. The previously underestimated role of environmental conditions has far‐reaching implications for our understanding of ecosystem functioning under changing climatic and soil conditions.
Equity investment, knowledge exploitation, and innovation performance for joint ventures
Authors: Lin Jun‐You
Published: September 2023

How is joint ventures' (JVs) innovation performance affected by their parent companies' equity investment and their exploitation of their parent firms' knowledge? We investigate 183 JV cases and examine the main effect of equity investment as well as the moderating effect of ambidexterity imbalance on the relationship between JVs' knowledge exploitation and exploration of their innovation performance. We utilize proprietary Securities Data Corporation (SDC) JV data combined with the National Bureau of Economic Research's (NBER) patent dataset to develop a mediated moderation model. The model indicates that equity investment is positively related to knowledge exploitation, which in turn has a positive effect on JVs' innovation; in addition, these relationships vary alongside ambidexterity imbalance. Our findings confirm the mediating role played by knowledge exploitation in JVs' innovative activities and highlight the tradeoff between organizational ambidexterity balance and knowledge exploitation as well as its influence on JVs' innovation performance. This research illuminates the foundations of JV innovation. Managerial implications are also discussed.
12th European Hidradenitis Suppurativa (EHSF) e.V. Conference—Facing HS according to the Renessaince style
Authors: Zouboulis Christos C. , Prignano Francesca
Published: September 2023

The—first hybrid—12th Conference of the European Hidradenitis Suppurativa Foundation (EHSF) e.V. took place on 8–10 February 2023 in Florence, Italy. With 198 high level scientific contributions and 757 participants from 45 countries, this 12th EHSF e.V. Conference has already been added to the EHSF's most unforgettable scientific activities. Twenty two active contributors were scientists and students under the age of 30 years and concurred for the three Young Investigator Awards. This special issue of Experimental Dermatology includes extended abstracts of the majority of the scientific lectures and posters. The 13th EHSF Conference will take place on February 7–9, 2024, as a physical presence event in Lyon, France. Dr. Philippe Guillem, Prof. Axel Villani and their team are glad to become your hosts.
The ISTH‐BAT score and outcomes after endometrial ablation in women with heavy menstrual bleeding
Authors: Eising Heleen P. , Punt Marieke C. , Schermer Tjard , Leemans Jaklien C. , Bongers Marlies Y.
Published: September 2023

Background

The International Society on Thrombosis and Haemostasis bleeding assessment tool (ISTH‐BAT), is used during the diagnostic workup of bleeding disorders. Data on ISTH‐BAT scores in women with heavy menstrual bleeding (HMB) undergoing endometrial ablation (EA) could be essential in optimizing HMB counselling.

Objective

To investigate the postsurgical incidence of amenorrhea, dysmenorrhea, quality of life, re‐intervention after EA, and ISTH‐BAT score.

Methods

This study included women who have undergone EA because of HMB. During a follow‐up of 2 to 5 years, ISTH‐BAT, pictorial blood assessment chart (PBAC), and Short Form‐36 survey (SF‐36) were administered. At 10 years of follow‐up surgical re‐interventions were evaluated.

Results

Seventy‐one women were included of whom 77% (n = 55) had an ISTH‐BAT score < 6, versus 23% (n = 16) ISTH‐BAT score ≥6 (mean age 46.3 versus 42.3, p = 0.004). In the ISTH‐BAT ≥6 group versus < 6 group, amenorrhea occurred in 63% (10/16) versus 82% (45/55) (p = 0.111), dysmenorrhea in 38% (6/16) versus 18% (10/55) (p = 0.111), and surgical re‐intervention in 19% (3/16) versus 25% (14/55) (p = 0.582). SF‐36 item (Bodily) pain was lower in the ISTH‐BAT ≥6 group versus < 6 (median score 58.7 vs. 80.0, p = 0.104).

Conclusions

An ISTH‐BAT score ≥6 may be related to a lower amenorrhea incidence and higher dysmenorrhea rate after EA.
Effect of different hydrophobic soybean isolated peptides and their zinc complexes on the growth and fermentation of Lactobacillus bulgaricus
Authors: Li Peiying , Xie Cuina , Zeng Qingzhu , Yuan Yang
Published: September 2023

This study was conducted to investigate the effects of the addition of different hydrophobic peptides and their zinc complexes on the growth and fermentation of lactic acid bacteria (LAB). According to the results of peptide surface hydrophobicity assays, three distinct hydrophobic peptides were isolated from soybean peptides (SP). The UV and FTIR measurements revealed that the peptide‐zinc complexes (SPZnC) were successfully prepared. The LAB group supplemented with ZnSPC exhibited significantly higher biomass, viable bacteria count, acid production capacity and glucose consumption compared to the LAB group supplemented with other components such as organic zinc, inorganic zinc and peptide. Among these supplements, Zn‐MHP demonstrated the most pronounced promotion of Lactobacillus growth and fermentation. Furthermore, additional fermentation experiments conducted on curdled fermented milk demonstrated that the inclusion of Zn‐MHP resulted in improved quality and reduced fermentation time. These findings suggest that Zn‐MHP possesses the ability to enhance the physiological function of LAB.
Author’s Response
Authors: Sonderegger Katherine
Published: September 2023

This essay aims to reply to the three essays devoted to Systematic Theology, volume 2. Common to all three essays is the conviction that my Trinitarian theology exhibits a kind of unicity that gives rise to inconsistencies of method and worries in matters of doctrine. My reply lays out several forms of unity and details how I hope to present proper uniformity in form and matter of dogmatics. A precis of my underlying Doctrine of Scripture and my forthcoming Christology is appended as well, as these prove central to the essayists' queries about the volume.
In vitro and in vivo evaluation of the antimicrobial effectiveness of non‐medicated hydrophobic wound dressings
Authors: Malone Matthew , Nygren Erik , Hamberg Tina , Radzieta Michael , Jensen Slade O.
Published: September 2023

There is an increasing use of non‐medicated wound dressing with claims of irreversible bacterial binding. Most of the data are from in vitro models which lack clinical relevance. This study employed a range of in vitro experiments to address this gap and we complemented our experimental designs with in vivo observations using dressings obtained from patients with diabetes‐related foot ulcers. A hydrophobic wound dressing was compared with a control silicone dressing in vitro. Test dressings were placed on top of a Pseudomonas aeruginosa challenge suspension with increasing concentrations of suspension inoculum in addition to supplementation with phosphate buffered saline (PBS) or increased protein content (IPC). Next, we used the challenge suspensions obtained at the end of the first experiment, where bacterial loads from the suspensions were enumerated following test dressing exposure. Further, the time‐dependent bacterial attachment was investigated over 1 and 24 h. Lastly, test dressings were exposed to a challenge suspension with IPC, with or without the addition of the bacteriostatic agent Deferiprone to assess the impacts of limiting bacterial growth in the experimental design. Lastly, two different wound dressings with claims of bacterial binding were obtained from patients with chronic diabetes‐related foot ulcers after 72 h of application and observed using scanning electron microscope (SEM). Bacteria were enumerated from each dressing after a 1‐h exposure time. There was no statistical difference in bacterial attachment between both test dressings when using different suspension inoculum concentrations or test mediums. Bacterial attachment to the two test dressings was significantly lower (p < 0.0001) when IPC was used instead of PBS. In the challenge suspension with PBS, only the hydrophobic dressing achieved a statistically significant reduction in bacterial loads (0.5 ± 0.05 log colony forming units; p = 0.001). In the presence of IPC, there was no significant reduction in bacterial loads for either test dressing. When bacterial growth was arrested, attachment to the test dressings did not increase over time, suggesting that the number of bacteria on the test dressings increases over time due to bacterial growth. SEM identified widespread adsorption of host fouling across the test dressings which occurred prior to microbial binding. Therein, microbial attachment occurred predominantly to host fouling and not directly to the dressings. Bacterial binding is not unique to dialkylcarbamoyl chloride (DACC) dressings and under clinically relevant in vitro conditions and in vivo observations, we demonstrate (in addition to previously published work) that the bacterial binding capabilities are not effective at reducing the number of bacteria in laboratory models or human wounds.
Alkaline electrolyzed water AS a potential green degreaser for meat processing stainless steel surface
Authors: Khalid Nurul Izzah , Ab Aziz Norashikin , Noh Teh Ubaidah , Abd Rahim Muhamad Hafiz
Published: September 2023

The meat industry faces significant challenges regarding removing fat, oil, and grease (FOG) residues from meat processing stainless steel surfaces, compounded by limited resources and inadequate cleaning knowledge. As an innovative solution to these difficulties, alkaline electrolyzed water (AlEW), a sustainable green degreaser, is proposed to replace the traditional alkaline wash. AlEW is produced through two–chamber (membrane) electrolysis at the cathode. AlEW with a strong reducing potential (−800 to −900 mV), high pH (10.0–11.5), and high dissolved oxygen are used to remove FOG residues from meat processing stainless steel surfaces. Our comprehensive analysis highlights the advantages of AlEW as a sustainable alternative to conventional degreasers for the meat industry, including ease of use, no storage requirements, and reduced costs for wastewater treatment. Our findings underscore AlEW's potential to improve the meat industry's quality, safety, and environmental sustainability. This review contributes to ongoing discussions about sustainable food industry solutions, aligning with the 2030 Agenda for Sustainable Development goals. In conclusion, AlEW is a promising alternative to conventional degreasers, advancing sustainability in the meat industry.

Practical Applications

This research introduces an innovative solution to a significant challenge in the meat processing industry—effective removal of fat, oil, and grease residues from equipment surfaces. Traditional methods involving costly and environmentally harmful chemicals have drawbacks. Our study proposes the use of alkaline electrolyzed water (AlEW) as a green degreaser. AlEW, generated by passing electric current through saltwater, exhibits high alkalinity that dissolves residues efficiently. This eco‐friendly approach not only ensures thorough cleaning but also reduces costs and addresses environmental concerns. By offering a sustainable and cost‐effective alternative, AlEW has the potential to revolutionize cleaning practices in the meat industry, enhancing food safety, operational efficiency, and sustainability. This advancement holds promise for wider adoption, benefiting both producers and consumers alike.
Environmental imprints of agricultural and livestock produce: A scoping review from South Asian countries
Authors: Sachdeva Barkha , Puri Seema , Aeri Bani Tamber
Published: September 2023

Background

Agricultural activities in 2020 have resulted in 5.5 billion tons of CO2 equivalent globally, which is expected to rise because the food system would have to grow 70% more food for the population in 2050. Research suggests that agricultural productivity in South Asian countries, will increase food security; however, the role of their food crops and livestock products in environmental imprints is uncertain. This review aimed to assess the environmental impacts resulting from pre‐ and post‐production agricultural activities related to edible food crops and livestock products consumed in eight South Asian countries.

Methods

Studies were retrieved using three databases (PubMed, Google Scholar and Science Direct) from 2011 to 2022. The protocol for this scoping review was not registered.

Results

Twenty‐seven studies met the inclusion criteria. Most studies were conducted in India. Twenty‐four articles assessed greenhouse gases (GHG) emissions, followed by water footprints (n = 5), nitrogen and phosphorus (N&P) emissions (n = 4), and land requirements (n = 4). The production of rice and wheat was identified as a significant contributor to GHG emissions. In India, Bangladesh and Sri Lanka, the production of livestock (meat/bovine/shrimp and milk) was reported to be harmful to the environment. Inconclusive data were retrieved for other environment variables.

Conclusions

Diversification in food production and cultivating additional coarse cereals (millets) offer opportunities for GHG reduction. Nevertheless, more comprehensive and longitudinal studies for South Asian countries are essential to make precise conclusions and validate the present review.
Fundamental Neurochemistry Review: Microglial immunometabolism in traumatic brain injury
Authors: Strogulski Nathan R. , Portela Luis V. , Polster Brian M. , Loane David J.
Published: September 2023

Traumatic brain injury (TBI) is a devastating neurological disorder caused by a physical impact to the brain that promotes diffuse damage and chronic neurodegeneration. Key mechanisms believed to support secondary brain injury include mitochondrial dysfunction and chronic neuroinflammation. Microglia and brain‐infiltrating macrophages are responsible for neuroinflammatory cytokine and reactive oxygen species (ROS) production after TBI. Their production is associated with loss of homeostatic microglial functions such as immunosurveillance, phagocytosis, and immune resolution. Beyond providing energy support, mitochondrial metabolic pathways reprogram the pro‐ and anti‐inflammatory machinery in immune cells, providing a critical immunometabolic axis capable of regulating immunologic response to noxious stimuli. In the brain, the capacity to adapt to different environmental stimuli derives, in part, from microglia's ability to recognize and respond to changes in extracellular and intracellular metabolite levels. This capacity is met by an equally plastic metabolism, capable of altering immune function. Microglial pro‐inflammatory activation is associated with decreased mitochondrial respiration, whereas anti‐inflammatory microglial polarization is supported by increased oxidative metabolism. These metabolic adaptations contribute to neuroimmune responses, placing mitochondria as a central regulator of post‐traumatic neuroinflammation. Although it is established that profound neurometabolic changes occur following TBI, key questions related to metabolic shifts in microglia remain unresolved. These include (a) the nature of microglial mitochondrial dysfunction after TBI, (b) the hierarchical positions of different metabolic pathways such as glycolysis, pentose phosphate pathway, glutaminolysis, and lipid oxidation during secondary injury and recovery, and (c) how immunometabolism alters microglial phenotypes, culminating in chronic non‐resolving neuroinflammation. In this basic neurochemistry review article, we describe the contributions of immunometabolism to TBI, detail primary evidence of mitochondrial dysfunction and metabolic impairments in microglia and macrophages, discuss how major metabolic pathways contribute to post‐traumatic neuroinflammation, and set out future directions toward advancing immunometabolic phenotyping in TBI.

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Mitigating wildfire losses via insurance‐linked securities: Modeling and risk management perspectives
Authors: Li Hong , Su Jianxi
Published: September 2023

This paper investigates the use of catastrophe (CAT) bonds as a risk management tool for wildfires. We introduce a set of Bayesian dynamic models designed to accurately represent wildfire losses, allowing a thorough examination of wildfire CAT bond pricing and hedge effectiveness. Our model captures crucial attributes of wildfire data, such as zero inflation, overdispersion, temporal fluctuations, and spatial dependence. Employing extensive quantitative analyses of US wildfire data, we highlight that CAT bonds can substantially mitigate tail risk associated with insurers' liability. Importantly, index‐based CAT bonds, drawing their payouts from aggregate wildfire losses over a larger geographical scope than an insurer's operational area, also provide effective hedges. Our research underscores the potential of wildfire CAT bonds as an enhancement to traditional reinsurance strategies, offering insurers an improved means to manage and mitigate wildfire exposures amidst inherent uncertainties.
Cucurbit chlorotic yellows virus, a crinivirus infecting Cannabis sativa plants
Authors: Gezovitch Orit , Luria Neta , Lachman Oded , Sela Noa , Smith Elisheva , Dombrovsky Aviv
Published: September 2023

High cannabidiol‐containing plants of Cannabis sativa (high‐CBD) growing in farms in Israel displayed foliar symptoms of interveinal chlorosis and yellowing, brittleness and occasionally necrosis. These symptoms, which were more apparent in older leaves, resembled those caused by the crinivirus lettuce chlorosis virus (LCV). However, this virus was not detected by reverse transcription (RT)‐PCR using specific primer sets. High‐throughput sequencing of viral RNA extracted from symptomatic leaves revealed the presence of cucurbit chlorotic yellows virus (CCYV), a crinivirus in the Closteroviridae family. The complete viral genome sequence was obtained using RT‐PCR followed by Sanger sequencing. The two CCYV RNA genomic segments shared 99.5%–99.85% nucleotide sequence identity with CCYV isolates from the GenBank. The virus was transmitted from symptomatic cannabis leaves to healthy plants of cannabis and Cucumis sativus ‘King Star’ (cucumber) by the whitefly Bemisia tabaci Middle Eastern Asia Minor 1 (MEAM1) species, causing disease symptoms identical to those of the donor plants. Cannabis‐CCYV was also transmitted between infected cucumber plants and cannabis seedlings of unknown genotype. Severe disease symptoms of yellowing and leaf‐edge necrosis were observed on high‐CBD and high Δ9‐tetrahydrocannabinol‐containing (high‐THC) flowering cannabis plants and were associated with mixed infections of LCV and CCYV. To the best of our knowledge, this is the first report of CCYV infecting C. sativa plants.
A cyberGIS approach to exploring neighborhood‐level social vulnerability for disaster risk management
Authors: Han Su Yeon , Kang Jeon‐Young , Lyu Fangzheng , Baig Furqan , Park Jinwoo , Smilovsky Danielle , Wang Shaowen
Published: September 2023

Timely identification of disaster‐prone neighborhoods and examination of disparity in disaster exposure are critical for policymakers to plan efficient disaster management strategies. Many studies have investigated racial, ethnic, and geographic disparities and populations most vulnerable to disasters. However, little attention has been paid to the development of easily accessible and reusable tools to enable: (1) the prompt identification of vulnerable neighborhoods; and (2) the examination of social disparity in disaster impact. In this research, we have developed a visual analytics tool that allows users to: (1) delineate neighborhoods based on their selection of variables; and (2) explore which neighborhoods are susceptible to the impacts of disasters based on specific socioeconomic and demographic characteristics. Through an exploration of COVID‐19 data in the case study, we revealed that the tool can provide new insights into the identification of vulnerable neighborhoods that need immediate attention for disaster control, management, and relief.
The effect of medical grade compression garments on the repeated‐bout effect in non‐resistance‐trained men
Authors: Brown Freddy , Hill Matt , Renshaw Derek , Pedlar Charles , Hill Jessica , van Someren Ken , Howatson Glyn , Tallis Jason
Published: September 2023

Whilst compression garments (CG) may enhance recovery from exercise‐induced muscle damage (EIMD), many recovery strategies can attenuate adaptative responses. Therefore, the effects of CG on recovery from EIMD, and the rapid protective adaptations known as the repeated bout effect (RBE) were investigated. Thirty‐four non‐resistance‐trained males (18–45 years) randomly received class II medical‐grade CG or placebo for 72 h following eccentrically‐focused lower‐body exercise, in a double‐blind, randomised controlled trial. Indices of EIMD were assessed at baseline, 0, 24, 48 and 72 h post‐exercise, before exercise and testing were repeated after 14 days. Results were analysed using a three‐way (time × condition × bout) linear mixed‐effects model. Exercise impaired isometric and isokinetic strength, with soreness and thigh circumference elevated for 72 h (P < 0.001). Compression did not enhance recovery (P > 0.05), despite small to moderate effect sizes (ES, reported alongside 90% confidence intervals) for isokinetic strength (ES from 0.2 [−0.41, 0.82] to 0.65 [0.03, 1.28]). All variables recovered faster after the repeated bout (P < 0.005). However, RBE for peak isokinetic force was impaired in CG at 60° s−1(group × bout interaction: χ2 = 4.24,P = 0.0395; ES = −0.56 [−1.18, 0.07]) and completely absent at 120° s−1(χ2 = 16.2,P < 0.001, ES = −0.96 [−1.61, −0.32]) and 180° s−1(χ2 = 10.4,P = 0.001, ES = −0.72 [−1.35, −0.09]). Compression blunted RBE at higher isokinetic velocities without improving recovery in non‐resistance‐trained males, potentially contraindicating their use following unaccustomed exercise in this population.
Longitudinal changes in intrinsic motoneuron excitability in amyotrophic lateral sclerosis are dependent on disease progression
Authors: Trajano Gabriel S. , Orssatto Lucas B. R. , McCombe Pamela A. , Rivlin Warwick , Tang Lily , Henderson Robert D.
Published: September 2023

Increased amplitude of persistent inward currents (PICs) is observed in pre‐symptomatic genetically modified SOD1 mice models of amyotrophic lateral sclerosis (ALS). However, at the symptomatic stage this reverses and there is a large reduction in PIC amplitude. It remains unclear whether these changes in PICs can be observed in humans, with cross‐sectional studies in humans reporting contradictory findings. In people with ALS, we estimated the PIC contribution to self‐sustained firing of motoneurons, using the paired‐motor unit analysis to calculate the Δfrequency (ΔF), to compare the weaker and stronger muscles during the course of disease. We hypothesised that, with disease progression, ΔFs would relatively increase in the stronger muscles; and decline in the weaker muscles. Forty‐three individuals with ALS were assessed in two occasions on average 17 weeks apart. Tibialis anterior high‐density electromyograms were recorded during dorsiflexion (40% of maximal capacity) ramped contractions, followed by clinical tests. ∆F increased from 3.14 (2.57, 3.71) peaks per second (pps) to 3.55 (2.94, 4.17) pps on the stronger muscles (0.41 (0.041, 0.781) pps, standardised difference (d) = 0.287 (0.023, 0.552), P = 0.030). ∆F reduced from 3.38 (95% CI 2.92, 3.84) pps to 2.88 (2.40, 3.36) pps on the weaker muscles (−0.50 (−0.80, −0.21) pps, d = 0.353 (0.138, 0.567), P = 0.001). The ALSFRS‐R score reduced 3.9 (2.3, 5.5) points. These data indicate that the contribution of PICs to motoneuron self‐sustained firing increases over time in early stages of the disease when there is little weakness before decreasing as the disease progresses and muscle weakness exacerbates, in alignment with the findings from studies using SOD1 mice.

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Key points

Research on mouse model of amyotrophic lateral sclerosis (ALS) suggests that the amplitude of persistent inward currents (PICs) is increased in early stages before decreasing as the disease progresses.

Cross‐sectional studies in humans have reported contradictory findings with both higher and lower PIC contributions to motoneuron self‐sustained firing.

In this longitudinal (∼17 weeks) study we tracked changes in PIC contribution to motoneuron self‐sustained firing, using the ΔF calculation (i.e. onset‐offset hysteresis of motor unit pairs), in tibialis anterior muscles with normal strength and with clinical signs of weakness in people with ALS.

ΔFs decreased over time in muscles with clinical signs of weakness. The PIC contribution to motoneuron self‐sustained firing increases before the onset of muscle weakness, and subsequently decreases when muscle weakness progresses.
Comparing and Evaluating Human and Computationally Derived Representations of Non-Semantic Design Information
Authors: Kwon Elisa , Goucher-Lambert Kosa
Published: September 2023

Design artifacts provide a mechanism for illustrating design information and concepts, but their effectiveness relies on alignment across design agents in what these artifacts represent. This work investigates the agreement between multi-modal representations of design artifacts by humans and artificial intelligence (AI). Design artifacts are considered to constitute stimuli designers interact with to become inspired (i.e., inspirational stimuli), for which retrieval often relies on computational methods using AI. To facilitate this process for multi-modal stimuli, a better understanding of human perspectives of non-semantic representations of design information, e.g., by form or function-based features, is motivated. This work compares and evaluates human and AI-based representations of 3D-model parts by visual and functional features. Humans and AI were found to share consistent representations of visual and functional similarities, which aligned well with coarse, but not more granular, levels of similarity. Human–AI alignment was higher for identifying low compared to high similarity parts, suggesting mutual representation of features underlying more obvious than nuanced differences. Human evaluation of part relationships in terms of belonging to the same or different categories revealed that human and AI-derived relationships similarly reflect concepts of “near” and “far.” However, levels of similarity corresponding to “near” and “far” differed depending on the criteria evaluated, where “far” was associated with nearer visually than functionally related stimuli. These findings contribute to a fundamental understanding of human evaluation of information conveyed by AI-represented design artifacts needed for successful human–AI collaboration in design.
Requirements, Objectives, Both, or Neither: How to Formulate Complex Design Problems for Innovation Contests
Authors: Vrolijk Ademir-Paolo , Szajnfarber Zoe
Published: September 2023

Technical organizations increasingly rely on innovation contests to find novel ideas for designing complex systems. These activities involve outsiders in the early stages of the design process, leading to ground-breaking designs that often surpass expectations. Here, the contest’s rules document plays a crucial role: this design artifact communicates the organization’s problem and the desired system performance to the participants—significantly impacting the resulting solutions. However, the contest’s nature amplifies the challenges of communicating complex design problems across boundaries. Existing strategies for formulating—i.e., requirement and objective allocation—might not suit this context. We developed an inductive model of their formulation process based on a multiyear field study of five complex innovation contests. We found that a formulation team (or “seeker”) balanced the need to communicate their problem in detail with the risk of excluding valuable participants. Here, they chose among three approaches—incentivize, impose, or subsume—depending on their knowledge of potential solutions and the participants’ capabilities. Notably, the seeker formulated more granularly than the literature describes, employing multiple approaches within each rules document. These findings shed light on a poorly understood aspect of innovation contests, shed new light on a longstanding debate in the engineering design literature, and guide practitioners’ formulation processes.
Numerical Investigation of the Heat Transfer Characteristics of Liquid Lithium Metal in Spiral Tubes
Authors: Liu Yongfu , He Yi , Tan Peng
Published: September 2023

The application of liquid lithium as a coolant for the forthcoming era of space nuclear reactors exhibits significant potential, and spiral tube heat exchanger components are commonly used in steam generators for reactors. However, the heat transfer characteristics of liquid lithium in spiral tubes are not yet fully understood. This research establishes a non-isothermal heat transfer model incorporating a modified turbulent Prandtl number to analyze the flow of liquid lithium through spiral tubes with varying geometries. Numerical analysis is carried out focusing on the influence of inlet velocity, the distribution of related parameters, and the geometry of spiral tubes. The results demonstrate that in the range of the dimensionless Dean number 8165–13,063, the Nusselt number and the pressure drop present approximately linear relations with the Dean number. For the distribution law of relevant physical quantities, the inner side of the tube displays an eye-anatomy low-flowrate area and a high-temperature area, while a low-pressure area forms on the inner pipe wall. Finally, the pitch and spiral radius are found to be reduced as much as possible to ensure high liquid lithium-based heat transfer performance with a small pressure drop. The optimized design parameters reveal that within the actual design range of non-dimensional pitch of 0.667–10.667 and curvature of 0.0556–0.1667, the non-dimensional pitch and curvature are 0.667–2.667 and 0.1667, respectively. This study offers valuable insights into the heat transfer properties of liquid lithium within heat exchangers of the spiral tube design, promoting its application in space nuclear reactor power supply.
The Effect of Heat Exchanger Tube Structure on the Condensation Heat Transfer of R1234ze(E)/R152a Inside Smooth Tubes
Authors: Dai Yuande , Tang Qingqing , Xu Chaoping
Published: September 2023

In this paper, the flow condensation heat transfer characteristics of the environmentally friendly nearly-azeotropic refrigerant R1234ze(E)/R152a (mass ratio of 40:60) in smooth tubes with varying structures were numerically investigated. Under the operating conditions of mass flux of 400 kg/m2/s, heat flux of 12 kW/m2, and saturation temperature of 308.15 K, this study investigated the influence of circular tube inner diameter, elliptical tube aspect ratio, and installation orientation on condensation heat transfer, while the influence on pressure drop has not been taken into account in the present study. The results indicate that the condensation heat transfer coefficient in the tube increases as the inner diameter of the circular tube decreases. The condensation heat transfer coefficient increases by 1.086 times when the circular tube inner diameter is reduced from 10.7 mm to 5 mm. Under identical operating conditions, the condensation heat transfer coefficient of the mixed refrigerant in elliptical tubes increases with an increase in the aspect ratio. The average condensation heat transfer coefficient increases by 18.21% as the aspect ratio of the elliptical tube increases from 1 to 2. Compared to a vertical elliptical tube, a horizontal elliptical tube is more favorable for condensation heat transfer within the tube.
High-Fidelity Simulation of the Interaction Between a Simplified Axial Compressor Cascade and an Ingested Vortex
Authors: Magand Dimitri , Deck Sébastien , Renard Nicolas , Dugeai Alain , Bois Béatrice , Spriet Tony
Published: September 2023

The aim of this research is to analyze the flow generated by the interaction between a simplified linear blade cascade of an industrial aircraft engine demonstrator and an ingested vortex with the aerodynamic characteristics of a ground vortex in real conditions. Due to the lack of experimental and high-fidelity numerical studies in the literature, a representative academic case of this phenomenon with a high-fidelity resolution of turbulence is performed and taken as reference. After the description of the computation setup and the numerical parameters used, the instantaneous topology of this complex flow is discussed, especially the interaction of the compressor cascade with the dynamics of the vortex. The hybrid RANS/LES simulation shows the chopping of the vortex, its destabilization and its dislocation into turbulent structures downstream the blade cascade. Turbulence is finely resolved in the blade wake and in the chopped vortex by the ZDES technique at a moderate computational cost thanks to RANS treatment of attached boundary layers. A decrease of the eddy viscosity injected in the URANS simulation allows a representation of the averaged vortical structures inside the vortex closer to the averaged reference case. Spectral analyses are performed on unsteady velocity signals from probes located inside and outside the vortex chopped by the blades, highlighting more turbulent structures inside the transformed vortex than in the wake of the blades, which are convected downstream in the direction of the Outlet Guide Vane (OGV).
Aerothermal Simulations and Testing of an Air-Cooled APU Bay
Authors: Ostino Léandre , Combébias Sébastien , Demolis Jacques
Published: September 2023

An Auxiliary Power Unit (APU) is an additional gas turbine engine located in a bay on an aircraft or a helicopter. The APU may be used to start the main engines, provide pressurized air to the cabin and generate electricity. Some of the equipment of the APU, such as the fuel metering pump or the ignitor, have certified temperature limits that must not be exceeded. In order to control the thermal environment around the APU, where these equipment are located, the bay needs to be cooled down when the APU is in operation. In this study, bay cooling is achieved with an ejector system.

Numerical simulations using ANSYS Fluent with a RANS (Reynolds Averaged Navier-Stokes) approach and a k-ω SST turbulence model have been performed to study the thermal environment of the APU in the bay. The volume inside the compartment, including many details such as oil and fuel ducts, was meshed using a complex wrapping process. The air-oil heat exchanger located at the inlet of the bay was modeled as a porous zone. Radiative, conductive and convective heat transfers were taken into account. The cooling mass flow through the bay and the surface temperature of all components were calculated.

These calculations have been compared to the results of a test campaign performed in a dedicated facility. During the tests, the APU was installed in a bay representative of the installation on the helicopter. The inlet of the bay was equipped with a calibrated bell mouth and thermal probes were installed on most of the equipment to monitor their temperature. Static and total pressure probes were also installed in the bay to evaluate the total pressure loss of the cooling flow. The comparisons between numerical and test results showed good correlation regarding the surface temperatures.
Simulation of the Thermoacoustic Response of an Aero-Engine Gas Turbine Fuel Injector Using a Hybrid CFD-CAA Method
Authors: Reinhardt Hanna , Alanyalıoğlu Çetin Ozan , Fischer André , Lahiri Claus , Nicolai Hendrik , Hasse Christian
Published: September 2023

Given the stringent emission regulations of aircraft engines, the trend in the aero industry is toward developing leaner combustion systems, which are prone to produce combustion instabilities. Hybrid methods of simultaneous acoustics and fluid dynamics simulations offer an elegant solution for the numerical prediction of these instabilities, taking advantage of the appropriate discretization of relevant scales. The presented work employed a hybrid simulation framework to identify the thermoacoustic response of a practically relevant configuration. The fluid dynamics were described using a CFD solver employing the low Mach formulation of the Navier-Stokes equations, while the acoustics were simulated using a CAA solver employing the acoustic perturbation equations. The coupling was implemented to exchange information between both solvers during runtime. The considered real-life configuration was designed to investigate the thermoacoustic behavior of realistic gas turbine injectors. It is acoustically excited to characterize the given injector via the flame transfer function approach under controlled operating conditions. The CFD simulation results were post-processed to obtain the acoustic behavior of the combustor. The reacting scattering matrix was constructed and then compared to the experimental reference, both obtained using the multi-microphone method. Finally, two different post-processing approaches were used to calculate the flame transfer function and discuss the applied hybrid computation method. This work demonstrated that the hybrid method can capture general features of the flame response of a complex three-dimensional combustion system.
Techno-Economic Analysis of Hydrogen and Ammonia as Low Carbon Fuels for Power Generation
Authors: Goldmeer Jeffrey , Buck Caroline , Suleiman Baha , Selim Hatem , Tayebi Kamel , Agostinelli Gian-Luigi , Dawood Alaaeldin
Published: September 2023

As the world focuses on the transition to low and zero-carbon energy systems, there are regions of the world that will continue to require imported fuels to meet their energy demands. In countries like Japan, renewable energy is not expected to meet all future energy demand. Therefore, these countries need to transition from importing carbon-based fossil fuels, to importing low or zero-carbon intensity fuels.

Focusing on carbon-free molecules, hydrogen and ammonia are of great interest. Hydrogen can be produced directly via reformation or pyrolysis of natural gas or from electrolysis of water, and because it can be used directly as a fuel. But there are well known challenges associated with hydrogen storage and transport. Due to the limited options for transporting liquid hydrogen, there is a growing interest in using ammonia as a method to ship hydrogen. Multiple countries are considering importing ammonia instead of hydrogen. Once imported the ammonia could be cracked back to hydrogen or potentially used directly in several end use applications, potentially including power generation.

However, there are trade-offs in the use of these fuels. Hydrogen has to be liquefied for transport. Producing ammonia requires added process steps. There are also impacts when using these fuels in a gas turbine. This paper will examine the issues in using these fuels in two parts. The first phase identifies the technical impacts of operating a gas turbine power plant on 100% hydrogen and 100% ammonia. The second phase examines the economic impact of the fuel selection, including the landed cost of the fuel and impact on levelized cost of electricity.
Microstructure and Mechanical Properties of NGB Joints Formed With B/Si Free Braze Alloys
Authors: Huang Xiao , Lowden Paul , Gontcharov Alex , Reis Robyn
Published: September 2023

In this research, boron free nickel-based braze alloys were examined in terms of their microstructure in narrow gap and wide gap configurations. The high temperature tensile properties of the standalone boron free braze alloys along with that of the narrow gap braze (NGB) joints with these alloys were also evaluated. The weldability of the boron free alloys was evaluated using bead-on-plate Tungsten Inert Gas (TIG) welding. NGB (with gap of ∼0.1 mm between two surfaces) was carried out using a substrate of GTD111. In addition, two commercial braze alloys, MTU Amdry 788 (A788) and Liburdi low boron braze alloy LW3PL, were incorporated in the tensile test matrix as baselines for comparison. The results from this study showed that the boron free alloy can be used as traditional braze welding rods for manual weld repair with good weldability. In addition, one of the boron free braze alloys, XH-1, possess higher tensile strengths than A788 braze alloy, due to the presence of gamma prime forming elements (Ti+Al). At 982 °C, NGB joint with XH-1 yielded tensile properties superior to that joined by LW3PL, i.e., higher strength and equivalent ductility. The high temperature tensile properties of the same joints showed similar yield and tensile strength values to that of the base metal GTD111, however, with lower ductility. Further improvement to brazing processes will be undertaken to improve the ductility of the boron free brazed joints in our future studies.
Propulsion Aerodynamics for a Novel High-Speed Exhaust System
Authors: Tsentis Spyros , Goulos Ioannis , Prince Simon , Pachidis Vassilios , Zmijanovic Vladeta
Published: September 2023

A key requirement to achieve sustainable high-speed flight and efficiency improvements in space access, lies in the advanced performance of future propulsive architectures. Such concepts often feature high-speed nozzles, similar to rocket engines, but employ different configurations tailored to their mission. Additionally, they exhibit complex interaction phenomena between high-speed and separated flow regions at the base, which are yet not well understood, but are critical in terms of pressure and viscous forces. This paper presents a numerical investigation on the aerodynamic performance of a representative novel exhaust system, which employs a high-speed, truncated, ideal contoured nozzle and a complex-shaped cavity region at the base. Reynolds-Averaged Navier-Stokes computations are performed for a number of Nozzle Pressure Ratios (NPRs) and free stream Mach numbers in the range of 2.7 < NPR < 24 and 0.7 < M∞ < 1.2 respectively. The corresponding Reynolds number lies within the range of 1.06 · 106 < Red < 1.28 · 106 based on the maximum diameter of the configuration. A decomposition of the drag domain forces exposes the major trends between the constituent elements. The impact of the cavity on the aerodynamic characteristics of the apparatus is revealed by direct comparison to an identical non-cavity configuration. Results show a consistent trend of increasing base drag with increasing NPR for all examined M∞ for both configurations. This is attributed to the jet entrainment effect and to the lower base pressure imposed by the higher jet flow expansion. The cavity region is found to have almost no impact on the incipient separation location of the nozzle flow. At low supersonic speeds of M∞ = 1.2 and high NPRs, the cavity has a significant effect on the aerodynamic performance, transitioning nozzle operation to under-expanded conditions. This results in approximately 12% higher drag coefficient compared to the non-cavity case and shifts the minimum NPR for which the system produces positive gross propulsive force to higher values.