bluuebunny/crossref_metadata_2025 huggingface dataset:
Deacetylation of chitin oligomers by Fusarium graminearum polysaccharide deacetylase suppresses plant immunity
Authors: Hu Su , Jin Minxia , Xu Yangjie , Wu Qin , Jiang Qiantao , Ma Jian , Zhang Yazhou , Qi Pengfei , Chen Guoyue , Jiang Yunfeng , Zheng Youliang , Wei Yuming , Xu Qiang
Published: September 2023

Chitin is a long‐chain polymer of β‐1,4‐linked N‐acetylglucosamine that forms rigid microfibrils to maintain the hyphal form and protect it from host attacks. Chitin oligomers are first recognized by the plant receptors in the apoplast region, priming the plant's immune system. Here, seven polysaccharide deacetylases (PDAs) were identified and their activities on chitin substrates were investigated via systematic characterization of the PDA family from Fusarium graminearum. Among these PDAs, FgPDA5 was identified as an important virulence factor and was specifically expressed during pathogenesis. ΔFgpda5 compromised the pathogen's ability to infect wheat. The polysaccharide deacetylase structure of FgPDA5 is essential for the pathogenicity of F. graminearum. FgPDA5 formed a homodimer and accumulated in the plant apoplast. In addition, FgPDA5 showed a high affinity toward chitin substrates. FgPDA5‐mediated deacetylation of chitin oligomers prevented activation of plant defence responses. Overall, our results identify FgPDA5 as a polysaccharide deacetylase that can prevent chitin‐triggered host immunity in plant apoplast through deacetylation of chitin oligomers.
Dynamic monitoring of TGW6 by selective autophagy during grain development in rice
Authors: Liu Zinan , Yang Qianying , Wu Pingfan , Li Yifan , Lin Yanni , Liu Wanqing , Guo Shaoying , Liu Yunfeng , Huang Yifeng , Xu Peng , Qian Yangwen , Xie Qingjun
Published: September 2023

Crop yield must increase to achieve food security in the face of a growing population and environmental deterioration. Grain size is a prime breeding target for improving grain yield and quality in crop.

Here, we report that autophagy emerges as an important regulatory pathway contributing to grain size and quality in rice. Mutations of rice Autophagy‐related 9b (OsATG9b) or OsATG13a causes smaller grains and increase of chalkiness, whereas overexpression of either promotes grain size and quality.

We also demonstrate that THOUSAND‐GRAIN WEIGHT 6 (TGW6), a superior allele that regulates grain size and quality in the rice variety Kasalath, interacts with OsATG8 via the canonical Atg8‐interacting motif (AIM), and then is recruited to the autophagosome for selective degradation. In consistent, alteration of either OsATG9b or OsATG13a expression results in reciprocal modulation of TGW6 abundance during grain growth. Genetic analyses confirmed that knockout of TGW6 in either osatg9b or osatg13a mutants can partially rescue their grain size defects, indicating that TGW6 is one of the substrates for autophagy to regulate grain development.

We therefore propose a potential framework for autophagy in contributing to grain size and quality in crops.
The vacuolar Ca2+ transporter CATION EXCHANGER 2 regulates cytosolic calcium homeostasis, hypoxic signaling, and response to flooding in Arabidopsis thaliana
Authors: Bakshi Arkadipta , Choi Won‐Gyu , Kim Su‐Hwa , Gilroy Simon
Published: September 2023

Flooding represents a major threat to global agricultural productivity and food security, but plants are capable of deploying a suite of adaptive responses that can lead to short‐ or longer‐term survival to this stress. One cellular pathway thought to help coordinate these responses is via flooding‐triggered Ca2+ signaling.

We have mined publicly available transcriptomic data from Arabidopsis subjected to flooding or low oxygen stress to identify rapidly upregulated, Ca2+‐related transcripts. We then focused on transporters likely to modulate Ca2+ signals. Candidates emerging from this analysis included AUTOINHIBITED Ca2+ ATPASE 1 and CATION EXCHANGER 2. We therefore assayed mutants in these genes for flooding sensitivity at levels from growth to patterns of gene expression and the kinetics of flooding‐related Ca2+ changes.

Knockout mutants in CAX2 especially showed enhanced survival to soil waterlogging coupled with suppressed induction of many marker genes for hypoxic response and constitutive activation of others. CAX2 mutants also generated larger and more sustained Ca2+ signals in response to both flooding and hypoxic challenges.

CAX2 is a Ca2+ transporter located on the tonoplast, and so these results are consistent with an important role for vacuolar Ca2+ transport in the signaling systems that trigger flooding response.
DNA methyltransferase 3A induces the occurrence of oral submucous fibrosis by promoting the methylation of the von Hippel–Lindau
Authors: Kuang Huifang , Yang Liyan , Li Zhixin , Wang Jinrong , Zheng Kaiyue , Mei Jie , Sun Honglan , Huang Yuqi , Yang Chao , Luo Wen
Published: September 2023

Background

Oral submucous fibrosis (OSF) is associated with malignant disorders. DNA methyltransferase 3A (DNMT3A) is a DNA methylesterase reported to be upregulated in multiple organs and shown to inhibit fibrosis. However, the detailed effect of DNMT3A on OSF remains unclear.

Methods

To mimic OSF in vitro, oral fibroblasts were exposed to arecoline and molecular biological experiments were performed to detect the function of DNMT3A in OSF.

Results

We found that von Hippel–Lindau (VHL) was downregulated and highly methylated in OSF. Arecoline remarkably increased the viability, invasiveness, and migration of oral fibroblasts, but upregulation of VHL partially reversed these effects. DNMT3A induces DNA hypermethylation in the VHL promoter, and VHL markedly inhibits the level of tenascin‐C (TNC) by inducing the ubiquitination of TNC. TNC reversed the inhibitory effect of VHL upregulation on the differentiation of oral fibroblasts into myofibroblasts.

Conclusion

DNMT3A induces OSF by promoting methylation of the VHL promoter. Hence, our study provides novel insights into the discovery of novel strategies that can be employed against OSF.
Stomatal aperture dynamics coupling mechanically passive and ionically active mechanisms
Authors: Cong Xue , Li Sien , Hu Dan
Published: September 2023

Stomata are the key nodes linking photosynthesis and transpiration. By regulating the opening degree of stomata, plants successively achieve the balance between water loss and carbon dioxide acquisition. The dynamic behaviour of stomata is an important cornerstone of plant adaptability. Though there have been miscellaneous experimental results on stomata and their constituent cells, the guard cells and the subsidiary cells, current theory of stomata regulation is far from clear and unified. In this work, we develop an integrated model to describe the stomatal dynamics of seed plants based on existing experimental results. The model includes three parts: (1) a passive mechanical model of the stomatal aperture as a bivariate function of the guard‐cell turgor and the subsidiary‐cell turgor; (2) an active regulation model with a target ion‐content in guard cells as a function of their water potential; and (3) a dynamical model for the movement of potassium ions and water content. Our model has been used to reproduce abundant experimental phenomena semi‐quantitatively. With accurately measured parameters, our model can also be used to predict stomatal responses to changes of environmental conditions.
Inventory and supply chain management with auto‐delivery subscription
Authors: Chen Shi , Lei Junfei , Moinzadeh Kamran
Published: September 2023

Auto‐delivery is a subscription model widely employed in supply chains, whereby a supplier delivers products to a buyer (or multiple buyers) according to the buyer's choice of a constant shipping quantity to be delivered at prescheduled dates. The buyer enjoys a discount for the auto‐delivery orders and other benefits, including free subscription and cancellation. Because these benefits seem to all accrue to the buyer at the supplier's expense, the rationale for the supplier's decision to offer auto‐delivery and its impact on the profitability of both parties is an intriguing concern. We first develop a model that consists of a supplier and a single buyer, whereby the supplier offers a discount for the auto‐delivery orders and the buyer chooses the auto‐delivery quantity with the flexibility of cancelling the subscription. We derive the two parties' operating characteristics of their inventory systems and examine their optimal decisions. Our analysis shows that buyers benefit from the auto‐delivery discount; the supplier benefits from the demand‐expansion effect and the inventory‐reduction effect, a potential discount on the cost of the auto‐delivery units; and the supply chain benefits from reducing the bullwhip effect. We also find that channel coordination requires the supplier to pass the inventory‐related savings to the buyer through the auto‐delivery discount, which depends on the ratio of the two parties' holding cost rates. Moreover, we examine a model extension whereby the supplier announces a discount that is available for multiple buyers, we show that the supplier's optimal auto‐delivery discount under exponential demand can be determined based on the aggregate‐level demand information from all buyers. Finally, we discuss another model extension whereby the lead time of the supplier's recurring orders for auto‐delivery is longer than that of the regular orders and present a full analysis of the case when the lead time differential is one time period.
Children's satisfaction with a comprehensive study program—Results from the LIFE Child cohort study
Authors: Bier Elisabeth , Vogel Mandy , Grafe Nico , Jurkutat Anne , Ludwig Juliane , Wagner Oleg , Meigen Christof , Kiess Wieland , Poulain Tanja
Published: September 2023

Background

Research participants' satisfaction is a topic of great interest, especially in the context of longitudinal studies. Evaluation also represents an important component of quality management in the health care system. Adult studies found that personal characteristics, e.g., age, sex, ethnicity, and SES, can influence satisfaction with health care or study participation. Studies on paediatric participants are sparse.

Objectives

To examine how children rated the study day of a cohort study and how these ratings were associated with sociodemographic and socioeconomic characteristics and retention in the context of a large cohort study.

Methods

Analyses were performed on 4‐ to 17‐year‐old participants of the German longitudinal cohort study LIFE Child (n = 2033). To assess the associations between overall satisfaction (high versus low/middle) and age, sex, body‐mass index, socioecomonic status, and participation in a follow‐up visit, we applied logistic mixed‐effects models.

Results

Participants' overall satisfaction with the LIFE Child study day was high (“very good”: 67.8%). Overall satisfaction was higher in 7–9 years olds (odds ratio [OR] 2.00, 95% confidence interval [CI 1.51, 2.66) and 10–12 years olds (OR 1.51, 95% CI 1.16, 1.98) than in 4–6 years olds and 13–17 years olds. Children with obesity were less likely to participate in a follow‐up visit (OR 0.56, 95% CI 0.39, 0.78). Children reporting high overall satisfaction at the first study visit completed a follow‐up visit more frequently (OR 1.32, 95% CI 1.05,1.67).

Conclusions

A high level of satisfaction increased participants' attendance at a follow‐up visit. Our results might be helpful for adapting the study program to the participants' needs in order to maximise retention and minimise attrition rates.
Metabolite profiling and screening of callus browning‐related genes in lotus (Nelumbo nucifera)
Authors: Deng Xianbao , Huang Jinghao , Zhang Minghua , Wei Xue , Song Heyun , Wang Yuxin , Xin Jia , Sun Heng , Liu Juan , Yang Dong , Li Jing , Yang Mei
Published: September 2023

Callus browning is a major drawback to lotus callus proliferation and regeneration. However, the underlying mechanism of its formation remains largely unknown. Herein, we aimed to explore the metabolic and molecular basis of lotus callus browning by combining histological staining, high‐throughput metabolomics, and transcriptomic assays for lotus callus at three browning stages. Histological stained brown callus cross sections displayed severe cell death symptoms, accompanied by an obvious accumulation of polyphenols and lignified materials. Widely targeted metabolomics revealed extensively decreased accumulation of most detected flavonoids and benzylisoquinoline alkaloids (BIAs), as well as a few phenolic acids, amino acids and their derivatives in callus with browning symptoms. Conversely, the contents of most detected tannins were significantly increased. Subsequent comparative transcriptomics identified a set of differentially expressed genes (DEGs) associated with the biosynthesis and regulation of flavonoids and BIAs in lotus. Notably, callus browning was coupled with significantly up‐regulated expression of two polyphenol oxidase (PPO) and 17 peroxidase (POD) encoding genes, while the expression of ethylene associated genes remained at marginal levels. These results suggest that lotus callus browning is primarily controlled at the level of metabolism, wherein the oxidation of flavonoids and BIAs is crucially decisive.
The effect of likelihood and impact information on public response to severe weather warnings
Authors: Taylor Andrea , Summers Barbara , Domingos Samuel , Garrett Natalie , Yeomans Sophie
Published: September 2023

Meteorological services are increasingly moving away from issuing weather warnings based on the exceedance of meteorological thresholds (e.g., windspeed), toward risk‐based (or “impact‐based”) approaches. The UK Met Office's National Severe Weather Warning Service has been a pioneer of this approach, issuing yellow, amber, and red warnings based on an integrated evaluation of information about the likelihood of occurrence and potential impact severity. However, although this approach is inherently probabilistic, probabilistic information does not currently accompany public weather warning communications. In this study, we explored whether providing information about the likelihood and impact severity of forecast weather affected subjective judgments of likelihood, severity, concern, trust in forecast, and intention to take protective action. In a mixed‐factorial online experiment, 550 UK residents from 2 regions with different weather profiles were randomly assigned to 1 of 3 Warning Format conditions (Color‐only, Text, Risk Matrix) and presented with 3 warnings: high‐probability/moderate‐impact (amber HPMI); low‐probability/high‐impact (amber); high‐probability/high‐impact (red). Amongst those presented with information about probability and impact severity, red high‐likelihood/high‐impact warnings elicited the strongest ratings on all dependent variables, followed by amber HPMI warnings. Amber low‐likelihood/high‐impact warnings elicited the lowest perceived likelihood, severity, concern, trust, and intention to take protective responses. Taken together, this indicates that UK residents are sensitive to probabilistic information for amber warnings, and that communicating that severe events are unlikely to occur reduces perceived risk, trust in the warning, and behavioral intention, even though potential impacts could be severe. We discuss the practical implications of this for weather warning communication.
Effectiveness of a native vein arteriovenous fistula tracking system
Authors: Meng Lingyan , Ng Jun Jie , Choong Andrew Mark Tze Liang , Dharmaraj Rajesh Babu , Menon Raj , Wong Julian Chi Leung , Ching Susan , Wong Yen Feng , Kong Jaqueline , Ho Pei
Published: September 2023

Objective

This study aims to evaluate the effectiveness of a tracking program on the functional maturation rate of arteriovenous fistula (AVF).

Methods

Two major clinical outcomes (commencement of cannulation and functional maturation) of created AVFs were compared between two cohorts. (i) Cohort 1: historical cohort; (ii) Cohort 2: AVFs created after implementation of the tracking project. Multivariable Cox regression models were used to assess the association between cohort allocation and the two major clinical outcomes.

Results

Data of 114 and 141 patients were analyzed respectively from Cohorts 1 (historical data) and 2 (with AVF tracking). After adjustment of covariates in the multivariable analysis, the AVFs created in Cohort 2 were more likely to be cannulated earlier (adjusted HR: 2.82; 95% CI: 1.97–4.05; p < 0.001), compared to those in Cohort 1. Similarly, the AVFs of Cohort 2 patients had significantly higher probability of functional maturation (adjusted HR: 1.81; 95% CI: 1.31–2.48; p < 0.001) than fistulas in Cohort 1. Cannulation was commenced for half of the AVFs by 4.1 months post‐creation in the historical cohort (Cohort 1), whereas in the post‐tracking cohort, 50% of the AVFs were cannulated by 2.3 months after creation (p < 0.001). It took 5.5 and 4.3 months for 50% of the AVFs created in Cohort 1 and Cohort 2 patients to achieve catheter‐free functional maturation, respectively (p = 0.06).

Conclusion

An AVF tracking program with maturation target for the access surgeons, together with a standardized tracking, feedback, and clinical strategy adjustment system is able to improve the AVF functional maturation rate.
Examining the relationship between metacognitive trust in thinking styles and supernatural beliefs
Authors: van Mulukom Valerie , Baimel Adam , Maraldi Everton , Farias Miguel
Published: September 2023

Conflicting findings have emerged from research on the relationship between thinking styles and supernatural beliefs. In two studies, we examined this relationship through meta‐cognitive trust and developed a new: (1) experimental manipulation, a short scientific article describing the benefits of thinking styles: (2) trust in thinking styles measure, the Ambiguous Decisions task; and (3) supernatural belief measure, the Belief in Psychic Ability scale. In Study 1 (N = 415) we found differences in metacognitive trust in thinking styles between the analytical and intuitive condition, and overall greater trust in analytical thinking. We also found stronger correlations between thinking style measures (in particular intuitive thinking) and psychic ability and paranormal beliefs than with religious beliefs, but a mixed‐effect linear regression showed little to no variation in how measures of thinking style related to types of supernatural beliefs. In Study 2, we replicated Study 1 with participants from the United States, Canada, and Brazil (N = 802), and found similar results, with the Brazilian participants showing a reduced emphasis on analytical thinking. We conclude that our new design, task, and scale may be particularly useful for dual‐processing research on supernatural belief.
First report of an outbreak of “Q” fever IN an abattoir from Argentina
Authors: Cardillo Natalia Marina , Bastos Reginaldo , García Araceli , Pérez Rosendo , García Ezequiel , Lloveras Susana , Suarez Carlos
Published: September 2023

In late October 2021, one of the veterinarians and the occupational physician of a bovine and swine abattoir from Entre Ríos Province, Argentina were alerted about workers with atypical pneumonia symptoms, raising suspicious of a possible Q fever outbreak. An outbreak epidemiological investigation was carried out. Analysis was based on the description of the study population, according to gender, age, symptoms, and position within the abattoir, as well as on outbreak epidemic curve and its probable origin. Cases of Q fever in the workers were confirmed by serology. Measurements of the association between the evaluated variables and the risk of exposure were investigated and calculated as attack rates. The outbreak occurred between October and November 2021, symptomatically affecting 11 workers, out of a total exposed population of 49 individuals. The index case was a 33‐year‐old male who started with symptoms on 27 October 2021, and the outbreak extended for at least 17 days. Workers in the clean zone of the slaughter floor had a 4.68 times higher risk of contracting Q fever than people located in other areas. Importantly, two pregnant cows were slaughtered a few days before the outbreak began, which could have been the origin of the outbreak. The present study demonstrates the urgent need to consider Q fever when diagnosing abortive diseases of ruminants in Argentina, as well as in zoonotic disease epidemiological surveillance to inform all actors of the health system.
The Analysis of World Information Warfare and Information Security in the Context of the Russian-Ukrainian War
Authors: Lysenko Serhii , Marukhovskyi Oleg , Krap Andrii , Illiuschenko Sergii , Pochapska Oksana
Published: September 2023

The appearance of significant transnational information processes has given rise to new threats to international security, such as information warfare. The problem of employing information warfare, which has become particularly acute and relevant, can be observed through the example of the full-scale war between the Russian Federation and Ukraine. Numerous information attacks by the aggressor country in the form of fake news dissemination confirm this. The latter requires in-depth study for the development of countermeasures, the application of combat algorithms, and the organization of modern information security.This article aims to introduce a methodology of information security based on several advanced defensive administrative measures, including a review of a series of response cycles to information attacks, mainly when conducted through hybrid and information technologies in the context of the Russian-Ukrainian war. Given the rapid dynamics of contemporary information processes and associated information threats, a complex set of countermeasures is necessary enabling an effective response to threats and timely prediction.The research methodology is based on general scientific and empirical methods of analysis and scientific cognition, including observation, systemic analysis, classification, scientific abstraction, statistical analysis, analogy, graphical generalization, and systematization. According to the results of the conducted research, it has been established that the distribution of managerial decisions into "fast" and "slow" allows for combining response to attacks with information accumulation to identify the most vulnerable elements and predict future information warfare. In particular, a process of responding to information attacks consisting of several stages of administrative measures has been proposed. Attention is given to the need to consider the initial data for further use in each relevant war period when repeating the cycle following the completion of the specified four-step countermeasure algorithm. Additionally, it has been identified that transmitting data on unlawful aggressor attacks to the information collection system requires careful planning and coordination among various operations and structures. The authors have substantiated and proposed the necessity and application of coordinated administrative measures among information security entities.
Pregnant nurses’ experiences of working shifts: a qualitative systematic review
Authors: Ooshige Narumi , Matsunaka Eriko , Ueki Shingo , Takuma Sayuka
Published: September 2023

Objective:

The objective of this systematic review was to synthesize the experiences of nurses who work shifts during pregnancy.

Introduction:

Pregnancy is a process of rapid physical change that requires adaptation both mentally and physically. Many women continue to work during pregnancy, including in the nursing profession, but there are various risks associated with working while pregnant.

Inclusion criteria:

This review included studies that focused on the experiences of pregnant registered nurses, regardless of their level of qualification, working shifts in any workplace, including hospitals, nursing home facilities, or clinics, in any country. Nurses not involved in direct care (eg, advanced practice nurses, administrators, educators) were excluded.

Methods:

The review followed the JBI methodology for qualitative systematic reviews. Published and gray literature were searched for via CINAHL (EBSCOhost), MEDLINE (EBSCOhost), PsycINFO (EBSCOhost), and Igaku Chuo Zasshi (Japan Medical Abstracts Society). No language restrictions were imposed, and the date limit was set for 2013 to 2021. Two independent reviewers performed data collection, extraction, critical appraisal, and analysis. Unequivocal and credible findings were used to develop categories, which were then synthesized to provide a set of comprehensive findings that were graded according to ConQual.

Results:

Five qualitative studies were included (2 from the USA, 2 from Japan, and 1 from Korea), from which 23 findings with narrative illustrations were extracted. Of these findings, 22 were assessed as unequivocal and 1 as credible. The studies were low to moderate quality based on the JBI critical appraisal checklist for qualitative research. All studies used qualitative methodologies, including phenomenology, qualitative description, and the grounded theory approach. Results were integrated into 8 categories and 3 synthesized findings. The first synthesized finding was that nurses struggle with the physical burden of pregnancy and work environments that threaten continued pregnancy. The second was that nurses achieve work–pregnancy compatibility by disclosing their pregnancy and obtaining support. The third was that development as a nurse results from continuing to work during pregnancy.

Conclusions:

Pregnant nurses face a harsh work environment; the support they receive after disclosing their pregnancy allows them to balance work and pregnancy; and they feel that they grow as professionals by continuing to work even if they are pregnant. More research is needed to inform support systems for pregnant nurses.

Review registration:

PROSPERO CRD42022309674

Supplemental digital content:

A Japanese-language version of the abstract of this review is available: http://links.lww.com/SRX/A31
Opportunities and Challenges for Co-Firing Ammonia in Coal-Fired Boilers
Authors: Rosinski Stan , Coleman Kent
Published: September 2023

Ammonia is being evaluated worldwide as an alternative energy carrier for hydrogen in future low-carbon energy scenarios. Ammonia is presently the second most produced chemical in the world. This global experience with ammonia has resulted in development of mature technologies for its production, handling, transport, and storage. The global supply chain already exists, and distribution infrastructure is well established locally in many countries. Additionally, safety regulations concerning the handling, transport, and storage of ammonia are well established. Ammonia could form the basis of an integrated energy storage and distribution decarbonization solution for multiple industries beyond its historic use in the production of fertilizers and other chemicals.

EPRI is evaluating the opportunities for coal/ammonia co-firing to understand the potential benefits in avoiding premature shutdown of valuable coal power generation assets and the technical challenges that may occur regarding degradation of boiler components (e.g., waterwalls, headers, piping) due to the changing combustion profile from ammonia co-firing. This paper summarizes ongoing research in ammonia co-firing with coal and discusses future applications.
Trigeneration System Replacement for a University Central Plant Boiler Facility
Authors: Mitri Frederick B. , Mukai Emily , Ponce Genesis , Anderson Kevin R.
Published: September 2023

This paper explores a replacement option for the heating boilers at the California State Polytechnic University, Pomona. The retrofit proposed uses solar thermal energy, thermal energy storage, and a combined cooling, heating, and power (CCHP) cycle with a focus on efficiency and reduced carbon emissions. The primary source of high-grade input heat energy for the Rankine cycle is a Concentrated Solar Power (CSP) farm. During times of high heating demand, steam is bled off to drive a lithium bromide (LiBr/H2O) cycle to produce auxiliary on-demand part load cooling and heating, with Coefficient of Performance (COP) values of COP = 1.5 (heating), and COP = 0.75 (cooling). The facility will produce up to 1.565 MW of electricity, 813.54 tons (2862 kW) of heating, and 220 tons (774 kW) of cooling. This system will utilize an 11-acre CSP facility to be located on the site of the former dorm units at the university. The CSP has a capacity factor of 34% and produces 4.260 MW of thermal energy which will be used to drive the reheat Rankine cycle. Equipment selection and specification using Commercial-off-the-shelf (COTS) components are cited herein. Economic analysis shows the Levelized Cost of Energy (LCOE) to be 8.10 ¢/kWh for the proposed trigeneration powerplant.
Investigation of Melting of PCM Dispersed With Nanoparticles in a Square Enclosure Integrated With Fins Subjected to a Uniform Magnetic Field: A Numerical Study
Authors: Sharma Akhalesh , Saxena Vivek , Joshi Jaykumar , Sahu Santosh K.
Published: September 2023

In this study, we examine the melting behavior of paraffin wax mixed with Cu0 nanoparticles within a square cavity that incorporates a triangular double fin. The investigation focuses on different nanoparticle concentrations (1% and 2%) and considers the melting process under constrained conditions. Two different arrangements of double fin are analyzed based on melting performance keeping the total area of fin constant. Arrangement with lower fin having longer length and shorter base has better melting performance. Melting performance increases with the addition of nanoparticles. The addition of 1% nanoparticles results in a notable enhancement in the melt rate. However, when the volume fraction of nanoparticles is further increased to 2%, the increase in the melt fraction becomes negligible in comparison to the 1% nanoparticle concentration. This is due to the increase in effective viscosity which negatively impacts the occurrence of natural convection, resulting in a less notable increase in the melt rate. Compared to single nanoparticles hybrid nanoparticles (Al2O3+CuO) perform better in terms of melting. Impact of uniform magnetic field on the melting of NePCM is examined by introducing the Lorentz force term into the momentum equation. Magnetic field is found to decrease the phenomenon of natural convection and, hence melting rate. However, the influence of magnetic field is found to be insignificant in the initial phases of the melting process. due to weak natural convection. The present work could be used for the optimization of LHTES unit integrated with fins and subjected to magnetic field in industries.
A Holistic Design Approach for a Micro Wind Turbine Powertrain
Authors: Claudio-Rodriguez Idalina L. , Santiago-Vargas Alex D. , Espinoza Albert A. , Aponte-Roa Diego A.
Published: September 2023

This paper proposes a holistic design methodology for a Micro Wind Turbine (MWT) powertrain. The design process integrates the design of an Axial-Flux Permanent Magnet (AFPM) Generator into the aerodynamic design methodology based on Blade Element Momentum (BEM) Theory. This approach shares aerodynamic blade inputs as parameters for the electromagnetic generator design. Tackling this as an integrated multidisciplinary design problem allows early identification of the limitations of the electrical and mechanical design domains. Early identification allows a more effective tuning and refinement of the design parameters. QBlade was used to simulate the performance of the blade design. A MATLAB script simulates the AFPM generator geometry on FEMM to determine the peak magnetic flux at the stator. The power curve simulation in MATLAB used the design parameters and a Thevenin equivalent circuit model to estimate the design performance.

A case study following the proposed methodology for a 20cm rotor MWT is presented to benchmark the model accuracy. Preliminary results show that the AFPM model matched the generator’s simulated power curve with 85% accuracy. The micro wind turbine prototype reached 10.5 W of nominal power at a wind speed of 15 m/s during testing at the 2022 Collegiate Wind Competition wind tunnel.
Experimental Analysis of an Elastohydrodynamic Seal for Supercritical Carbon Dioxide Turbomachinery
Authors: Henry Jonah , Xu Hanping , Hassan Mohammad Fuad , Cesmeci Sevki , Islam Mohammad Towhidul , Liu Shuangbiao , Tang Jing
Published: September 2023

To unlock the potential of sCO2 power cycles, technology readiness must be demonstrated on the scale of 10–600 MWe and at the sCO2 temperatures and pressures of 350–700 °C and 20–35 MPa for nuclear industries. The lack of suitable shaft seals in sCO2 operating conditions is one of the main challenges at the component level. So far, conventional seals all suffer from the incapability of handling sCO2 pressure and temperature in one way or another. To this end, we propose an elastohydrodynamic (EHD) high-pressure, high-temperature, and scalable shaft seal for sCO2 cycles. The unique mechanism of such an EHD seal provides a self-regulated constriction effect to restrict the flow without substantial material contact, thereby minimizing leakage and wear. In this study, we conducted an experimental study to prove the EHD seal concept on a 2″ static shaft. The shaft was made from stainless steel, whereas the test seal was made from PEEK. The experiments were performed for 12.7 μm initial clearance, and the operating pressure was increased up to 5 MPa. It was observed that the EHD seal throttled the leakage rate successfully. The leakage rate increased to a maximum of 2 g/s at around 4MPa before it started to decay to 1.75 g/s at the maximum operating pressure of 5 MPa. This unique behavior of the EHD seal could become advantageous for sCO2 turbomachinery, where lower leakage rates are required at high pressure and temperature values.
Evaluating Critical Weather Parameters Using Machine Learning Models
Authors: Najian Maede , Goudarzi Navid
Published: September 2023

Wind speed and temperature forecasting accurately for an urban area are two critical elements to mitigate cost and energy in engineering calculations. Recently, researchers have employed a combination of mesoscale Weather Research and Forecasting (WRF) and microscale models of Computational Fluid Dynamics (CFD) to simulate wind flow in urban areas. Employing machine learning algorithms is also introduced as another promising alternative/complementary tool. In this work, a WRF model is developed to calculate wind speed at 10m above the ground in two different residential regions with different upwind roughness in Singapore. The results are validated by the literature. Using the validated model, Recurrent Neural Network (RNN) models are developed to compare with numerical weather models and evaluate their performance in prediction. Prediction results’ accuracy is evaluated using Root Mean Square Error (RMSE) and Mean Absolute Percentage Error (MAPE), and obtained errors below 0.19 and 5%, respectively. The models can provide high-resolution data as boundary conditions for CFD modeling at the local/building scale, which leads to understanding the more realistic behavior of the flow field in a built environment. In addition, they support an extended range of urban microclimate analysis, renewable energy integration practices, and smart city planning efforts.
Transient Multi-Fuel Performance Modelling of a Utility Scale Boiler
Authors: Johnson Michael D. , Hübel Moritz
Published: September 2023

Following the trends of integrating intermittent renewable energy into the electrical grids, design processes and tools for thermal power plants are changing. Utility-scale boilers are complex thermodynamic systems, which consist of components like combustors, heat exchangers, pumps, or valves. These components are well understood in principle and can be described with fundamental physical equations such as mass, energy, and species balances as well as heat transfer, and pressure loss correlations. Evolving computational performance and transient system simulation tools allow the coupling of these components and the creation of system models which support the design process to adapt to the energy market trends.

The paper will give insights into the underlying modelling approaches and assumptions for a commercial, 540MW boiler design process. System model validation for a wide load range will be shown based on plant measurement data. The paper will cover the implementation of an innovative dual-fuel combustion model, which allows switching from 100% coal operation to 100% natural gas operation. In addition, ramp-rate studies will be presented, affecting critical operational data such as temperature differences in critical headers causing thermal stress. The presented approach serves plant designers, owners, and operators to increase safety, reduce commissioning times and maximize output.
Numerical Modeling of an Elastohydrodynamic Seal Design for Supercritical CO2 Power Cycles
Authors: Cesmeci Sevki , Ejiogu Ikenna , Rahman Md Mahmudur , Hassan Mohammad Fuad , Xu Hanping , Tang Jing
Published: September 2023

Supercritical carbon dioxide (SCO2) leakage has been one of the major issues in sCO2 power cycles, penalizing the cycle efficiencies. The effect of the seal leakage on the cycle efficiency could be as high as 0.65% for a utility sCO2 power cycle. Therefore, there is a pressing need for effective sealing solutions to get the full benefit of sCO2 power generation technology. To offer a potential solution, we propose an Elasto-Hydrodynamic (EHD) seal that can work at elevated pressures and temperatures with low leakage and minimal wear. The EHD seal has a very simple, sleeve like structure, wrapping on the rotor with minimal initial clearance at 25 to 50μm levels. In this work, a proof-of-concept study for the proposed EHD seal was presented by using the Reynolds equation, Lame’s formula, Barus Equation, and Dowson-Higginson formula to model the pressure distribution along the seal clearance as well as the seal deformation. The numerical modeling of the seal was carried out in Matlab using its built-in ordinary differential equation solver. The seal was evaluated for a 2″ diameter test seal with a pressure range of 0.2 MPa to 20 MPa. At the high pressure of 20 MPa, the clearance height at the throat (ht) was found to be 24.7 μm which is about 50.6% than the initial seal clearance (h0) of 50 μm, which resulted in a mass flow rate of 0.00162 kg/s. The presented analytical study lays a solid foundation for future model developments that could be used in the design of the proposed EHD seal.
Failure Analysis of OTSG Tube in a Cogeneration Power Plant
Authors: Tina Wahida , Donaldson Elizabeth , Dickinson Thomas E.
Published: September 2023

Tube leakage is one of the most frequent causes of Once Through Steam Generator (OTSG) tube failure. A leaking tube was discovered within the OTSG unit of the Cogeneration Plant of 100 MW. The failed section of the tube was removed from the steam generator. Several metallurgical examinations of this tube segment were performed to identify the failure mode and cause. The results of the metallurgical evaluation revealed that the tubing was furnished to the chemical requirements of ASME Specification SB 407 and UNS N08800 alloy. The subject tube failure involved a through-wall crack that occurred as stress corrosion cracking. Residual stresses in the tube, created from forming of the tube at the time of manufacturing, combined with flow-induced stresses experienced in service as the steam generator operated, resulted in the formation of longitudinal cracking. The cracking formed and extended gradually into and through the tube wall, influenced by corrosion products in the cracks until the failure occurred. Additions of solutions used in boiler water treatment practices potentially induced corrosive substances into the tube. It is suggested that the tubes, especially the lower ones, of the OTSG are not located in a confined space.
Broad and potent neutralizing antibodies are elicited in vaccinated individuals following Delta/BA.1 breakthrough infection
Authors: Seow Jeffrey , Shalim Zayed A. , Graham Carl , Kimuda Simon , Pillai Aswin , Lechmere Thomas , Kurshan Ashwini , Khimji Atika M. , Snell Luke B. , Nebbia Gaia , Mant Christine , Waters Anele , Fox Julie , Malim Michael H. , Doores Katie J.
Published: September 2023

Despite the success of COVID-19 vaccines in preventing infection and/or severe disease, there has been an increase in SARS-CoV-2 infections in vaccinated individuals owing to the waning vaccine-derived immunity, and the emergence of new variants which encode escape mutations in Spike. Following breakthrough infection in vaccinated individuals, an increase in neutralization breadth has been observed in sera/plasma. However, how exposure to a heterologous Spike broadens the neutralizing response at the monoclonal antibody (mAb) level is not fully understood. Through isolation of 119 mAbs from three individuals receiving two doses of BNT162b2 vaccine before becoming Delta or Omicron/BA.1 infected, we show that serum breadth occurs due to the presence of somatically mutated mAbs with broad neutralization activity indicative of re-activation and maturation of B cells generated through previous COVID-19 vaccination. Isolated mAbs frequently show reduced neutralization of current circulating variants including BA.2.75.2, XBB, XBB.1.5, and BQ.1.1 confirming continuous selective pressure on Spike to evolve and evade neutralization. However, isolation of mAbs that display effective cross-neutralization against all variants indicates the presence of conserved epitopes on the receptor binding domain and a lesser extent the N-terminal domain. These findings have implications for the selection of Spike antigens for next-generation COVID-19 vaccines.

IMPORTANCE

With the emergence of SARS-CoV-2 viral variants, there has been an increase in infections in vaccinated individuals. Here, we isolated monoclonal antibodies (mAbs) from individuals experiencing a breakthrough infection (Delta or BA.1) to determine how exposure to a heterologous Spike broadens the neutralizing antibody response at the monoclonal level. All mAbs isolated had reactivity to the Spike of the vaccine and infection variant. While many mAbs showed reduced neutralization of current circulating variants, we identified mAbs with broad and potent neutralization of BA.2.75.2, XBB, XBB.1.5, and BQ.1.1 indicating the presence of conserved epitopes on Spike. These results indicate that variant-based vaccine boosters have the potential to broaden the vaccine response.
GBS hyaluronidase mediates immune suppression in a TLR2/4- and IL-10-dependent manner during pregnancy-associated infection
Authors: Coleman Michelle , Orvis Austyn , Brokaw Alyssa , Furuta Anna , Sharma Kavita , Quach Phoenicia , Bhullar Avneet , Sanghavi Rhea , Nguyen Shayla , Sweeney Erin , Seepersaud Ravin , Armistead Blair , Adams Waldorf Kristina M. , Rajagopal Lakshmi
Published: September 2023

Bacterial infections remain a significant cause of adverse pregnancy outcomes. Ascending infection of group B streptococcus (GBS) or
Streptococcus agalactiae
from the lower genital tract to the amniotic cavity leads to fetal injury, preterm births, or stillbirths. Factors increasing the invasive potential of bacteria at the maternal-fetal interface are poorly understood. Previous studies have indicated that the GBS hyaluronidase (HylB) can enhance systemic infection by breaking down host hyaluronan into disaccharides that dampen protective TLR2 and TLR4 signaling. Here, we examined the importance of hyaluronan receptors such as TLR2, TLR4, and CD44 in defense against GBS infections during pregnancy. While HylB promoted ascending GBS infection in wild-type (WT) and CD44-deficient mice, surprisingly, mice lacking both TLR2 and TLR4 (TLR2/4) were able to curtail these infections. Interleukin-10 (IL-10) and IL-10-expressing macrophages were significantly increased in the uterine tissues of WT mice during infection with HylB-proficient GBS compared with those of TLR2/4-deficient mice, and this likely promotes immune suppression and GBS dissemination. Consistent with these observations, pregnant IL-10-deficient mice exhibited diminished GBS ascension and dissemination. Similarly, the administration of a blocking antibody against the IL-10 receptor (IL-10R) in WT mice diminished ascending GBS infection. Collectively, these observations indicate that HylB promotes immune suppression in a TLR2/4- and IL-10-dependent manner to enhance the invasive potential of GBS during pregnancy-associated infections.

IMPORTANCE

Bacteria such as GBS can cause infections during pregnancy leading to preterm births, stillbirths, and neonatal infections. The interaction between host and bacterial factors during infections in the placenta is not fully understood. GBS secretes a hyaluronidase enzyme that is thought to digest host hyaluronan into immunosuppressive disaccharides that dampen TLR2/4 signaling, leading to increased bacterial dissemination and adverse outcomes. In this study, we show that GBS HylB mediates immune suppression and promotes bacterial infection during pregnancy that requires TLR2, TLR4, and IL-10. Understanding the interaction between host and bacterial factors can inform future therapeutic strategies to mitigate GBS infections.
Coding-complete genome of human alphaherpesvirus 1 isolated from a case of fulminant hepatitis
Authors: Viljoen Natalie , Burt Felicity , Weyer Jacqueline
Published: September 2023

We report the coding-complete genome sequence of human alphaherpesvirus 1 (HHV1) isolated from a previously healthy 64-year-old male with fulminant hepatitis, a rare presentation of a common viral agent. The sequence is highly similar to previously described HHV1 sequences. Additional sequence data for fulminant hepatitis cases are required.
A high-throughput structural system biology approach to increase structure representation of proteins from
Clostridioides difficile
Authors: Rosas-Lemus Monica , Dey Supratim , Minasov George , Tan Kemin , Anderson Spencer M. , Brunzelle Joseph , Nocadello Salvatore , Shabalin Ivan , Filippova Ekaterina , Halavaty Andrei , Kim Youngchang , Maltseva Natalia , Osipiuk Jerzy , Minor Wladek , Joachimiak Andrzej , Savchenko Alexei , Anderson Wayne F. , Satchell Karla J. F. ,   Center for Structural Biology of Infectious Diseases team members
Published: September 2023

Clostridioides difficile
causes life-threatening gastrointestinal infections. It is a high-risk pathogen due to a lack of effective treatments, antimicrobial resistance, and a poorly conserved genomic core. Herein, we report 30 X-ray structures from a structure genomics pipeline spanning 13 years, representing 10.2% of the X-ray structures for this important pathogen.
Whole-genome sequence of
Paenibacillus
sp.
,
isolated from soil, Fort Collins, Colorado, USA
Authors: Kiehl Paris M. , Cagle Shelby M. , Kinkel Traci L. , Stenglein Mark D.
Published: September 2023

A whole genome sequence of a
Paenibacillus
sp. bacterium isolated from soil in Fort Collins, Colorado was obtained. This bacterium was of particular interest due to its antibiotic potential against Gram-positive pathogen surrogates.
Isolating and characterizing cluster AB Mycobacteriophage NoShow, which encodes lysis proteins shared with cluster H2 phages
Authors: Niblock Danielle J. , Winkler Anne R. , Curtin Caroline E. , Kokinda Jacqui F. , Danker Walter A. , Llorente Fernandez Ignacio , Smith Ava R. , Ali Asad , Cruz Gabrielle G. , Givvines Leya C. , Lee-Soety Julia Y.
Published: September 2023

We present here Mycobacteriophage NoShow, isolated from a soil sample collected on the Maguire Campus of Saint Joseph’s University in Merion Station, Pennsylvania. Even though NoShow’s 52,825 bp genome is most similar to phages in cluster AB, its
lysA
and
lysB
genes are most similar to phages in cluster H2.