bluuebunny/crossref_metadata_2025 huggingface dataset:
The increased aspartate levels in transgenic cotton (Gossypium hirsutum L.) lead to improved tolerance against whitefly (Bemisia tabaci, Gennadius)
Authors: Gul Ambreen , Rao Abdul Qayyum , Ahmed Mukhtar , Latif Ayesha , Bakhsh Allah , Iftikhar Sehrish
Published: August 2024

The whitefly, a polyphagous insect pest feeding on nearly 1328 plant species, is a major threat to global cotton production and incurs up to 50% yield losses in cotton production in Pakistan. We investigated whether increased aspartate in phloem sap imparts whitefly toxicity and protects cotton plants from intense damage. The enzymatic step for aspartate production is carried through aspartate aminotransferase (AAT). In this study, we constitutively overexpressed the Oryza sativa cytoplasmic AAT (OsAAT2) under the CaMV35S promoter in Gossypium hirsutum cv. CIM‐482. Real‐time PCR analysis of the AAT transcripts revealed a 2.85‐ to 31.7‐fold increase in mRNA levels between the different cotton lines. A substantial increase in the free‐amino acid content of the major N‐assimilation and transport amino acids (aspartate, glutamate, asparagine, and glutamine) was seen in the phloem sap of the transgenic cotton lines. The bioassay revealed that the two transgenic cotton lines with the highest free aspartate content in the phloem sap exhibited 97 and 94% mortality in the adult whitefly population and a 98 and 96% decline in subsequent nymph populations, respectively. There was also a significant change in the physiological behaviour of the transgenic cotton lines, with an increased net assimilation (A), gaseous exchange (Gs) and rate of transpiration (E). Improved morphological characteristics like plant height, total number of bolls and fiber yield were recorded in transgenic cotton lines. The AAT gene shows promise in mitigating whitefly infestations and enhancing the overall health and yield of cotton plants.
Exploring expressed emotion and its influencing factors among family caregivers of dementia people: a 3‐month study in Japan
Authors: Liu Xiaoji , Kanaya Reiko , Shigenobu Kazue , Takiue Keigo , Mo Wenping , Koujiya Eriko , Takeya Yasushi , Yamakawa Miyae
Published: August 2024

Background

Family caregivers of dementia patients face significant challenges, including managing their own emotional responses. Understanding factors influencing expressed emotion (EE) is crucial for effective support interventions. The aim of this study was to explore and describe changes in EE among family caregivers of dementia and its associated factors at different time points over 3 months.

Methods

A 3‐month observational study was conducted in Japan. We collected demographically detailed data on family caregivers currently providing care, including care burden, relationship closeness, and depression. We assessed EE using the validated Family Attitude Scale (FAS). After adjustment for multiple confounding factors, multivariate linear regression analysis was performed to assess factors affecting EE at various time points. Linear regression analysis with generalised estimating equations was used to assess associations between 3‐month time‐varying EE and burden, intimacy, and depression.

Results

Fifty‐six family caregivers completed the study. Changes in FAS scores did not show statistical differences over 3 months. It is worth noting that the degree of relationship closeness and care burden are important influencing factors of EE in both cross‐sectional analysis and longitudinal analysis.

Conclusions

Early identification of risk factors can aid in developing interventions aimed at preventing high levels of EE in the dementia family, thereby mitigating their detrimental effects. Tailored interventions are essential to enhance caregiver well‐being and cultivate positive caregiver–patient relationships.
Can transcutaneous auricular vagus nerve stimulation mitigate vigilance loss? Examining the effects of stimulation at individualized versus constant current intensity
Authors: Luna Fernando G. , Lupiáñez Juan , König Stefanie , Garscha Ulrike , Fischer Rico
Published: August 2024

According to the arousal model of vigilance, the locus coeruleus‐norepinephrine (LC‐NE) system modulates sustained attention over long periods by regulating physiological arousal. Recent research has proposed that transcutaneous auricular vagus nerve stimulation (taVNS) modulates indirect physiological markers of LC‐NE activity, although its effects on vigilance have not yet been examined. Aiming to develop a safe and noninvasive procedure to prevent vigilance failures in prolonged tasks, the present study examined whether taVNS can mitigate vigilance loss while modulating indirect markers of LC‐NE activity. Following a preregistered protocol (https://osf.io/tu2xy/), 50 participants completed three repeated sessions in a randomized order, in which either active taVNS at individualized intensity set by participant, active taVNS set at 0.5 mA for all participants, or sham taVNS, was delivered while performing an attentional and vigilance task (i.e., ANTI‐Vea). Changes in salivary alpha‐amylase and cortisol concentrations were measured as markers of LC‐NE activity. Self‐reports of feelings associated with stimulation and guessing rate of active/sham conditions supported the efficacy of the single‐blind procedure. Contrary to our predictions, the observed vigilance decrement was not modulated by active taVNS. Pairwise comparisons showed a mitigation by active taVNS on cortisol reduction across time. Interestingly, Spearman's correlational analyses showed some interindividual effects of taVNS on indirect markers of LC‐NE, evidenced by positive associations between changes in salivary alpha‐amylase and cortisol in active but not sham taVNS. We highlight the relevance of replicating and extending the present outcomes, investigating further parameters of stimulation and its effects on other indirect markers of LC‐NE activity.
Exposed Aquaculture Operations: Strategies for Safety and Fish Welfare
Authors: Bjelland Hans Vanhauwaert , Folkedal Ole , Føre Heidi Moe , Grøtli Esten Ingar , Holmen Ingunn Marie , Lona Eivind , Slette Hans Tobias , Størkersen Kristine Vedal , Thorvaldsen Trine
Published: August 2024

The expansion of aquaculture production into more exposed harsh and remote ocean environments presents both new opportunities and challenges. To manage the complexities of exposed operations, research into fish welfare, personnel safety, and facilitating technology is thus of key importance. This paper reviews recent research advances in the areas of safety, fish welfare, and technology, while the focus is on the Norwegian salmon farming industry, the results could benefit exposed fish farming internationally. Regarding fish welfare, the study summarizes the current knowledge status of salmon coping abilities and welfare indicators in strong currents and waves. On the safety front, there has been significant progress in operational safety management, accident analysis, and emergency preparedness, all of which are crucial for human personnel in these demanding settings. Human safety and fish welfare also rely on structures and equipment, and recent research results include advances in environmental load analysis, vessel design, simulations of fish farms. Notably, the development of contact‐free, autonomous lifting operations, and hole detection methods represents a significant leap in maintaining aquaculture infrastructure. This multidisciplinary study underscores the need for integrated research approaches to address exposed aquaculture, emphasizing that while recent innovations have enhanced safety and robustness, ongoing research and new strategies are critical for safety and fish welfare in exposed aquaculture operations.
Exploring the Nexus of Steroidal Hormone Receptor, Uterine VEGF Expression and NADPH‐d Interaction in Buffalo Uterus During Oestrous Cycle With Seasonal Variation
Authors: Dehury Sagarika , Uppal Varinder , Pathak Devendra , Gupta Anuradha
Published: August 2024

The reproductive efficiency in buffalo is highly influenced by seasonal variability. Angiogenesis in the reproductive cycle is important for optimal physiological functioning of uterus. Estrogen receptor‐α (ERα), vascular endothelial growth factor (VEGF) and reduced nicotinamide adenine dinucleotide phosphatase diaphorase (NADPH‐d) are vital indicators for the uterine angiogenic process. This study was conducted to see the effect of season on the expression of different uterine angiogenic factors. Season wise (winter and summer) and phase wise (follicular and luteal), immune staining intensity of buffalo uterus was measured by calculating the optical density value (OD) for ERα and VEGF. Percentage of immuno‐positive cell count for ERα was done. Histoenzymic NADPH‐d expression was analysed. Expression of all these factors increased during follicular phase of oestrous cycle in order to support the angiogenesis; however, the expression was significantly lower (p ≤ 0.05) in term of OD value as well as percentage count of immuno‐positive cells during summer season indicating lower angiogenic activity that subsequently affected reproduction in buffalo.
Genotyping of Holstein Cows by SELL, MX1 and CXCR1 Gene Loci Associated With Mastitis Resistance
Authors: Muslimova Zhadyra , Abdualiyeva Assem , Shaugimbayeva Nurzhan , Orynkhanov Kanat , Ussenbekov Yessengali
Published: August 2024

Mastitis is a significant factor that decreases milk production in cows of different breeds in Kazakhstan. The objective of this study was to determine the genetic makeup of Holstein cows by analysing specific gene loci (SELL, MX1, CXCR1+291C>T and CXCR1+1093C>T) that are linked to resistance against mastitis. The goal was to identify cows with favourable genotypes that are less prone to udder diseases. At the SELL gene locus c.567T>C, all three genetic variants were identified in the control population with the respective frequencies: TT (0.20), CT (0.44), and CC (0.36). Genetic variation was also detected at the MX1 gene c.567T>C, CXCR1 c.+291C>T and CXCR1+1093C>T loci. Deviation from the expected Hardy–Weinberg equilibrium was observed for two gene loci, MX1 g.143182088 and CXCR1+1093C>T, with increased chi‐square values of 10.6261 and 9.7137, respectively. The analysis of subclinical mastitis incidence indicates that cows carrying the heterozygous CT genotype at the L‐selectin gene locus exhibit greater resistance to the disease. Animals carrying the CCCCCT genotype at the MX1 c.567T>C, CXCR1 c.+291C>T and CXCR1+1093C>T gene loci were discovered to have a significant likelihood of developing subclinical mastitis. This suggests that these genes could serve as potential indicators of susceptibility to the condition. The practical significance of this study lies in determining the frequency of genotypes linked to mammary gland morbidity in Holstein breeding farms in Kazakhstan.
Religion and female labor force participation in India
Authors: Kar Sujata
Published: August 2024

This paper primarily aims to identify the impact of religion on currently working women in India by considering the National Family Health Survey 2015–2016 data. It also incorporates several socioeconomics variables as controls. The models are estimated with aggregate as well as disaggregated urban–rural as well as zonal data. The results suggest that compared to the Hindus, Christian and Buddhist women have higher odds of labor force participation and Muslim and Sikh women have lower odds. Extensive analysis of the data indicates that economic well‐being among the Sikhs and the status of being married among the Muslims could be the primary factors responsible for their lower workforce participation. Additionally, lower age, lower education, better economic well‐being, the status of being married, large family size, having only one child, male household heads, and younger children are associated with lower workforce participation. Furthermore, education seems to be more accessible to women from urban areas and wealthier sections. Based on these observations, the study recommends devising policies for greater provisions for higher education in rural areas and among the poorer sections of society. Also, imparting awareness and developing an understanding of the importance of female labor force participation is crucial to improve women's labor force participation in India.
Determinants and international transmission of interest rates: Do foreign reserves and sovereign debt matter?
Authors: Afonso António , Huart Florence , Jalles João Tovar , Stanek Piotr
Published: August 2024

We analyze the role of international reserves and sovereign debt in the determination and international transmission of interest rates. We develop a model that describes the money market equilibrium with capital account openness. It predicts that higher levels of international reserves lead to lower interest rates whereas the effect of higher government debt is ambiguous. We then test empirically these predictions on a panel of 128 countries over 1985–2019. We find that: (i) the transmission of U.S. interest rates to domestic interest rates is stronger in emerging market economies (EMEs) than in advanced economies (AEs) for short‐term interest rates (STIR), and vice versa for long‐term interest rates (LTIR); (ii) international reserves help counteract the transmission of the U.S. policy rate on STIR in EMEs; (iii) a higher sovereign debt level is associated with lower interest rates in EMEs (liquidity effect), but higher interest rates in developing economies (risk premium effect).
Mechanism of action of montmorillonite powder on injury and repair factors in Stage II pressure ulcers in model mice
Authors: Li Xiaofei , Zhao Jinying
Published: August 2024

Background

This study aims to elucidate the therapeutic effects and underlying mechanisms of montmorillonite powder on wound healing in mice with Stage II pressure ulcers, thereby providing a robust foundation for its clinical application in the treatment of such ulcers.

Materials and methods

Sixty 8‐week‐old specific pathogen‐free male BALB/c mice were randomly allocated into three groups: a model group (where Stage II pressure ulcers were induced using the magnet pressure method and the wounds were dressed with gauze soaked in 0.9% sodium chloride solution), a treatment group (where, following the induction of Stage II pressure ulcer models, wounds were uniformly treated with montmorillonite powder), and a control group (where magnets were placed in the same location without exerting magnetic pressure). Skin histopathology was assessed via light microscopy. Wound healing progress over various intervals was quantified utilizing Image‐Pro Plus software. Histopathological alterations in the wounds were examined through hematoxylin and eosin (H&E) staining. The expression of growth factor proteins within the wound tissue was analyzed using the streptavidin–peroxidase method. Furthermore, the levels of vascular endothelial growth factor (VEGF), collagen types I and III (COL‐I, COL‐III) proteins were quantified via Western blotting, serum concentrations of inflammatory mediators in mice were determined by enzyme‐linked immunosorbent assay, and the levels of oxidative stress markers in wound tissues were measured using UV‐visible spectrophotometry.

Results

The treatment group exhibited significantly reduced serum levels of interleukin‐1β, interleukin‐6, and tumor necrosis factor‐alpha, and elevated levels of interleukin‐4 compared to the model group (p < 0.05). Additionally, the expression of transforming growth factor‐beta1, basic fibroblast growth factor, epidermal growth factor, VEGF, COL‐I, and COL‐III proteins in wound tissues was significantly higher in the treatment group than in the model group (p < 0.05). Levels of superoxide dismutase and glutathione peroxidase in wound tissues were higher, and levels of malondialdehyde were lower in the treatment group compared to the model group (p < 0.05).

Conclusion

Montmorillonite powder facilitates wound healing and augments the healing rate of Stage II pressure ulcers in model mice. Its mechanism of action is likely associated with mitigating wound inflammation, reducing oxidative stress damage, promoting angiogenesis, and enhancing the synthesis of growth factors and collagen.
The novel HLA‐DPB1*04:02:01:44 allele identified in a volunteer bone marrow donor
Authors: Khamaganova Ekaterina , Leonov Evgeny , Pavlova Irina , French Albert J. E. , Hopper Sebastian J. F.
Published: August 2024

Nucleotide substitution in the intron 2 of HLA‐DPB1*04:02:01:01 results in a novel allele, HLA‐DPB1*04:02:01:44.
Molecular insights into OPR gene family in Saccharum identified a ScOPR2 gene could enhance plant disease resistance
Authors: Sun Tingting , Wu Qibin , Zang Shoujian , Zou Wenhui , Wang Dongjiao , Wang Wenzhi , Shen Linbo , Zhang Shuzhen , Su Yachun , Que Youxiong
Published: August 2024

12‐Oxo‐phytodienoic acid reductases (OPRs) perform vital functions in plants. However, few studies have been reported in sugarcane (Saccharum spp.), and it is of great significance to systematically investigates it in sugarcane. Here, 61 ShOPRs, 32 SsOPRs, and 36 SoOPRs were identified from R570 (Saccharum spp. hybrid cultivar R570), AP85‐441 (Saccharum spontaneum), and LA‐purple (Saccharum officinarum), respectively. These OPRs were phylogenetically classified into four groups, with close genes similar structures. During evolution, OPR gene family was mainly expanded via whole‐genome duplications/segmental events and predominantly underwent purifying selection, while sugarcane OPR genes may function differently in response to various stresses. Further, ScOPR2, a tissue‐specific OPR, which was localized in cytoplasm and cell membrane and actively response to salicylic acid (SA), methyl jasmonate, and smut pathogen (Sporisorium scitamineum) stresses, was cloned from sugarcane. In addition, both its transient overexpression and stable overexpression enhanced the resistance of transgenic plants to pathogen infection, most probably through activating pathogen‐associated molecular pattern/pattern‐recognition receptor‐triggered immunity, producing reactive oxygen species, and initiating mitogen‐activated protein kinase cascade. Subsequently, the transmission of SA and hypersensitive reaction were triggered, which stimulated the transcription of defense‐related genes. These findings provide insights into the function of ScOPR2 gene for disease resistance.
Evaluation of the Amount of Compounded Chemotherapy Drugs: A Comparison Between Nine Compounding Pharmacies
Authors: Bajorek Samantha R. , Hazzah Trina N. , Chretin John D. , Mills Tracy N. , McKee Talon S. , Frank Jennifer R. , Benvin‐Guzzo Jessica L. , Clifton Kary A. , Bergman Philip J.
Published: August 2024

The use of compounded formulations of chemotherapy in veterinary medicine is common. The purpose of this study was to evaluate the drug amount of two compounded chemotherapeutics (chlorambucil and cyclophosphamide) from multiple veterinary compounding pharmacies, to determine if there was a difference in drug amounts between those that came from 503A versus 503B pharmacies, and finally to determine heterogeneity in drug amounts within each individual pharmacy. Nine veterinary compounding pharmacies (eight 503A, one 503B) were sampled in total, with two different batches sampled from each pharmacy. Each capsule's actual concentration was compared to the intended (prescribed) concentration. Of the 68 total samples obtained, 20 (29%) tested outside the FDA‐acceptable discrepancy of ±10%. Of these, 12 (60%) were chlorambucil and 8 (40%) were cyclophosphamide. 503A cyclophosphamide samples had an average discrepancy of 6.6% from the intended dose while samples from the 503B pharmacy had a discrepancy of 1.8%. 503A chlorambucil samples had an average discrepancy of 10.4% from the intended dose while samples from the 503B pharmacy had a discrepancy of 9.6%. Heterogeneity within the same pharmacy and batch ranged from 0.1% to 51% for the 503A pharmacies and 2.6% to 7.5% for the 503B pharmacy. Heterogeneity between different batches within the same pharmacy ranged from 0.4% to 58.3% for the 503A pharmacies and 5% to 14.8% for the 503B pharmacy. Although the drug amounts of compounded cyclophosphamide and chlorambucil manufactured by the 503B compounding pharmacy was more reliably maintained compared to that compounded by the 503A pharmacies, there was ultimately still potential for variability in drug amounts regardless of the pharmacy designation.
Use of preoperative erythropoietin‐stimulating agents is associated with decreased thrombotic adverse events compared to red blood cell transfusion in surgical patients with anaemia
Authors: Choi Una E. , Nicholson Ryan C. , Frank Steven M. , Cha Stephanie , Cho Brian C. , Lawton Jennifer S. , Lester Laeben C. , Hensley Nadia B.
Published: August 2024

Background and Objectives

Preoperative red blood cell (RBC) transfusions increase post‐operative venous thromboembolic (VTE) events. Erythropoietin‐stimulating agents (ESAs) increase VTE risk in cancer patients; we aimed to assess ESA versus RBC‐associated VTE risks in a broad population of surgical patients.

Materials and Methods

We queried TriNetX Diamond Network from 2006 to 2023, comparing patients with anaemia within 3 months preoperatively who received preoperative ESAs with or without intravenous (IV) iron to patients who received preoperative RBCs. Sub‐analyses included (1) all surgeries and (2) cardiovascular surgeries.

We propensity score matched for demographics, comorbidities, medical services, post‐treatment haemoglobin (g/dL) and, for all‐surgery comparisons, surgery type. Outcomes included 30‐day post‐operative mortality, VTE, pulmonary embolism (PE), disseminated intravascular coagulation (DIC) and haemoglobin.

Results

In our 19,548‐patient cohorts, compared with preoperative RBC transfusion, ESAs without IV iron were associated with lower mortality (relative risk [RR] = 0.51 [95% confidence interval (CI), 0.45–0.59]), VTE (RR = 0.57 [0.50–0.65]) and PE (RR = 0.67 [0.54–0.84]). Post‐operative haemoglobin was higher in the ESA without IV iron cohort compared with the transfusion cohort (10.0 ± 1.4 vs. 9.4 ± 1.8 g/dL, p = 0.002). Cardiac surgical patients receiving ESAs with or without IV iron had lower risk for post‐operative mortality, VTE and PE (p < 0.001) than those receiving RBCs. Post‐operative haemoglobin differed between patients receiving ESAs with IV iron versus RBCs (10.1 ± 1.5 vs. 9.4 ± 1.9 g/dL, p = 0.0009).

Conclusion

Compared with surgical patients who were transfused RBCs, ESA recipients had reduced 30‐day post‐operative risk of mortality, VTE, PE and DIC and increased haemoglobin levels. IV iron given with ESAs improved mortality.
Use of cannulated screws in the treatment of unicondylar humeral condylar fractures in dogs
Authors: Whyte MacKenzie A. , Murphy Sean M. , Won Wade W. , Weng Hsin‐Yi , Malek Sarah
Published: August 2024

Objective

To describe unicondylar humeral fracture (UHF) repair using cannulated transcondylar screws, report postoperative fracture reduction, healing, and complication rates.

Study design

Retrospective.

Animals

A total of 49 client owned dogs with UHF.

Methods

Surgical technique and approach (i.e., open, limited open, or minimally invasive) were recorded. Articular step defect (ASD) and gap (Gap) at the humeral condylar articular surface were measured on pre‐ and postoperative images and reported as percentages. Fracture healing was graded on follow‐up radiographs. Functional outcome was based on client questionnaire over the phone. General linear models were used to assess the impact of surgical approach on %ASD, %Gap, whereas Cox regression was used to assess prognostic factors of full fracture healing.

Results

A total of 49 fractures repaired with a transcondylar screw with or without an antirotational pin(s) were included. Surgical approach did not have an impact on postoperative %ASD, %Gap or development of complications. The overall complication rate was 26% (11/42), with no revision surgery necessary. Of the dogs that encountered complications, 50% required pin and/or screw removal after fracture healing. For 29 dogs with a minimum of four‐month owner telephone questionnaire follow‐up, 90% reported no lameness and only three reported intermittent lameness. Achieving complete fracture healing was affected by increased postoperative %ASD (p = .033).

Conclusion

The UHFs repaired by transcondylar cannulated screws had acceptable outcomes and fracture reduction with complication rates being similar regardless of the surgical approach.

Clinical significance

Cannulated screws can be implanted with varying surgical approaches to successfully repair UHFs with comparable clinical outcome to previous reports.
Intensive and critical care nurses patient safety, care quality, professional self‐efficacy, and missed nursing care: Structural equation model analysis
Authors: Berdida Daniel Joseph E.
Published: August 2024

Background

Globally, nurses' patient safety, care quality, and missed nursing care are well documented. However, there is a paucity of studies on the mediating roles of care quality and professional self‐efficacy, particularly among intensive and critical care unit (ICCU) nurses in developing countries like the Philippines.

Aim

To test a model of the interrelationships of patient safety, care quality, professional self‐efficacy, and missed nursing care among ICCU nurses.

Methods

A cross‐sectional, correlational design study was used. ICCU nurses (n = 335) were recruited via consecutive sampling from August to December 2023 and completed four validated self‐report scales. Spearman Rho, structural equation modeling, mediation, and path analyses were utilized for data analysis.

Results

The emerging model demonstrated acceptable fit parameters. Patient safety positively influenced care quality (β = .34, p = .002) and professional self‐efficacy (β = .18, p = .011), while negatively affecting missed nursing care (β = −.34, p = .003). Care quality positively and negatively influenced professional self‐efficacy (β = .40, p = .003) and missed nursing care (β = −.13, p = .003), respectively. Professional self‐efficacy indirectly impacted missed nursing care (β = −.32, p = .003). Care quality (β = −.10, p = .003) and professional self‐efficacy (β = .13, p = .003) showed mediating effects between patient safety and missed nursing care.

Linking Evidence to Action

ICCU nurses' care quality and professional self‐efficacy are essential mediating factors that can bolster patient safety practices, hence reducing missed nursing care. Therefore, healthcare organizations, nurse managers, and policymakers should cultivate care quality and self‐efficacy by creating support programs and providing a positive practice environment. Nurses and nurse supervisors could directly observe missed nursing care in the ICCU to understand its underreported causes.
A Numerical Study of Crack Penetration and Deflection at the Interface Between Peritubular and Intertubular Dentin
Authors: Xu Min , Xu Zhangying , An Bingbing
Published: August 2024

Dentin is a biological composite exhibiting multilevel hierarchical structure, which confers excellent damage tolerance to this tissue. Despite the progress in characterization of fracture behavior of dentin, the contribution of composite structure consisting of peritubular dentin (PTD), intertubular dentin (ITD) and tubules to fracture resistance remains elusive. In this study, calculations are carried out for energy release rate associated with crack propagation in the microstructure of dentin. Crack penetration and deflection at the PTD–ITD interface are accounted for in the numerical analyses. It is found that high stiffness of the PTD plays a role in increasing crack driving force, promoting crack growth in the microstructure of dentin. For crack penetration across the PTD–ITD interface, the crack driving force increases with increasing tubule radius; and thick PTD generates amplified crack driving force, thereby leading to weak fracture resistance. The driving force for crack deflection increases with the increase in tubule radius in the case of short cracks, while for long cracks, there is a decrease in driving force with increasing tubule radius. Furthermore, we show that the competition between crack penetration and deflection at the PTD-ITD interface is controlled by the ratio of PTD to ITD elastic modulus, tubule radius and thickness of PTD. High PTD stiffness can increase the propensity of crack deflection. The microstructure of dentin with large tubule radius favors crack deflection and thick PTD is beneficial for crack penetration.
IndRNN-Based Data-Driven Modeling Integrated With Physical Knowledge for Engine Performance Monitoring
Authors: Xiao Dasheng , Xiao Hong , Wang Zhanxue
Published: August 2024

Monitoring the whole performance status of aircraft engines is of paramount importance for ensuring flight safety, control system, and prognostic health management. This work introduced an aircraft engine deep learning (DL) model that integrated with engine physical knowledge. First, component networks were established for each engine component (e.g., fan, turbine, nozzle) using the independently recurrent neural network (IndRNN), self-attention mechanism, and residual network. Subsequently, based on the physical spatial alignment of engine components, the data transfer between component networks was determined to establish the whole engine model. Case studies were conducted on exhaust gas temperature (EGT) prediction for two civil aircraft engines and thrust prediction for another two turbofan engines. When processing the actual engine running data, the data augmentation method was invested to address the issue of nonuniform distribution of engine working states in the training data. Compared with three pure data-driven models based on IndRNN, recurrent neural network, and long short-term memory (LSTM), the model introduced in this work demonstrated superior precision in both steady states and transient states. Specifically, the achieved mean absolute relative error (MARE) was 0.54% for EGT prediction and 0.41% for thrust prediction. When adjusting the time-steps, the introduced model showed steadier predictions with minimal MARE fluctuation compared to the three pure data-driven models, enhancing overall predictive stability.
Generative Design of a Gas Turbine Combustor Using Invertible Neural Networks
Authors: Krueger Patrick , Gottschalk Hanno , Werdelmann Bastian , Krebs Werner
Published: August 2024

The need to burn 100% H2 in high efficient gas turbines featuring low NOx combustion in premix mode requires the complete redesign of the combustion system to ensure stable operation without any flashback. Since all engine frames featuring a power range from 4 MW up to 600 MW are affected, a huge design effort is expected. To reduce this effort, especially to transfer knowledge between the different engine classes, generative design methods using latest AI technology will provide promising potential. In this work, this challenge is approached utilizing the current advances in generative artificial intelligence. We train an invertible neural network (INN) on an expandable database of geometrically parameterized combustor designs with simulated performance labels. Utilizing the INN in its inverse direction, multiple design proposals are generated, which fulfill specified performance labels.
Dynamic Modeling of Spatially Varying Shape Memory Alloy Unimorph Actuators
Authors: Kennedy Scott , Vlajic Nicholas , Perkins Edmon
Published: August 2024

Shape memory alloys are a class of soft actuators that can recover strain through a phase change and are capable of biomimetic motion. Despite the advantages of these alloys (e.g., high strength-to-weight ratios, inexpensive cost, and small form factor), their major drawbacks (e.g., limited deformation, complex modeling, and low operating frequency) have limited their practical use. Incorporating these alloys into morphing structures increases their deformation profile but also increases the complexity of modeling. Here, continuous shape memory alloy phase kinetic equations are used to calculate the state of the material and are paired with a dynamic beam model in order to model the dynamic response of these morphing structures. A constant cross section, varying cross section, and series combination actuators are experimentally tested in order to assess the model’s accuracy for varying actuator dimensions. The root mean square errors were 1.60 mm and 1.65 mm for a constant cross section and varying cross section actuator, respectively. Additionally, two unimorph actuators were combined in series and experimentally tested with a payload mass of 10 g and 30 g resulting in an average root mean square error of 1.00 mm and 0.73 mm with a displacement of 21.14 mm and 10.48 mm, respectively. This model proves to be accurate for a variety of actuator configurations and external conditions, which enables shape memory alloy morphing actuators to be more easily designed and implemented in soft robotics and other systems.
Aerodynamic Noise Generated in Three-Dimensional Lock-In and Galloping Behavior of Square Cylinder in High Reynolds Number Turbulent Flows
Authors: Cheng Zhi , Wu Ying , Dowell Earl H. , Lien Fue-Sang
Published: August 2024

The flow dynamics and aeroacoustics propagation for flow-induced vibration system consisting of three-dimensional flow past an elastically-mounted square cylinder are investigated using the Ffowcs Williams–Hawkings method and detached eddy simulation model for the first time. Previous experimental and numerical data are compared with the results obtained by models implemented in this work to validate the correctness of the present hybrid modeling. The representative reduced velocities, spanning from lock-in to galloping regimes of concerned configurations, are chosen for investigation with the Reynolds number fixed at 6.67 × 104. The structural response of the present fluid-induced vibration (FIV) system exhibits the feature of “vortex-induced vibration–galloping instability,” and the pattern of wake dynamics is determined into “wake-locked instability” or “wake-unlocked instability“ based on the specific vortex-shedding behavior. Specifically, the wake dynamics of the FIV system at a reduced velocity of 30 involve spatially concentrated vortex-shedding behaviors compared to smaller reduced velocities, leading to the corresponding higher-frequency components in the pressure spectrum. Furthermore, the enhancement of structural amplitude leads to the increasing energy of acoustics pressure, but structural amplitude is not the only decisive factor in determining the power of sound pressure level. The impermeable surface could provide the turbulence-induced noise source which increases the power of broadband frequency. The phase differences of acoustics pressure fluctuation between loading and thickness noise components will suppress the overall noise energy and the variation of phase differences is correlated to the position of sound monitors as well as reduced velocities.
First-principles calculations on adsorption-diffusion behavior of transition layer Ti atoms on the Fe surface
Authors: Han Haiwei , Chen Chunyan , Bian Shunuo , Yu Lihua , Xu Junhua , Wu Xinmeng , Jiang Yaohong , Zhao Lijun
Published: August 2024

When preparing films through magnetron sputtering, atoms of the target material ejected during sputtering adhere, diffuse across the surface, condense, nucleate, and grow on the substrate surface, ultimately forming a film. However, due to the short time scales involved in this process, it is difficult to acquire detailed knowledge about the adsorption, surface diffusion, and film formation of target material atoms on the substrate surface in experimental settings. Therefore, this paper employs first-principles calculation methods to investigate the strongest adsorption sites, optimal diffusion paths, and the impact of diffusion distance of Ti atoms on the Fe(110) and Fe(100) surfaces on the film’s microstructure. Through theoretical calculations, this study enriches the theoretical understanding of this process, providing a theoretical basis for the design and analysis of experimental schemes. The calculation results indicate that the adsorption energy of Ti atoms is the highest at the B sites on the Fe(100) surface. The diffusion barrier for Ti atoms on the Fe(100) surface is the lowest, making it easier for Ti atoms to diffuse on this surface. Under the condition of a relative substrate temperature labeled as Ts/Tm<0.3, the average diffusion distance of Ti atoms on the Fe(100) surface is the greatest, facilitating the formation of T-zone structures with superior mechanical properties.
Optimized thermoelectric performance of flexible Bi0.5Sb1.5Te3 thin film through PbTe incorporation
Authors: Zhang Rensheng , Tian Xujiang , Liang Shaojun , Zhu Hanming , Yue Song
Published: August 2024

Being the most widely applied thermoelectric materials near room temperature, (Bi,Sb)2Te3 alloys have to face the performance deterioration above 400 K due to their intrinsic narrow bandgap. Increasing the dominant hole concentration and expanding the bandgap have been proven as effective strategies to suppress bipolar excitation through elemental substitution and nanoscale compositing. Herein, PbTe-incorporated Bi0.5Sb1.5Te3 thin films were deposited on flexible polyimide substrates through intermittent magnetron cosputtering. The introduction of tiny amount of PbTe was found to have significant influences on the microstructure and orientation, atomic compositions, and carrier concentration. Profiting from the enhanced carrier concentration and altered effective mass, the descending in Seebeck coefficient above 400 K can be effectively inhibited, accompanied with the distinctly improved electrical conductively. Finally, the highest power factor of 16.38 μW cm−1 K−2 at 420 K and the highest average power factor of 14.62 μW cm−1 K−2 in the temperature range of 300–540 K were obtained in the Bi0.5Sb1.5Te3/PbTe composite film containing 0.25% Pb, with the increments of 28.2% and 38.2% from those of the PbTe-free Bi0.5Sb1.5Te3 film, respectively. These values are competitive among the flexible Bi0.5Sb1.5Te3 thin films fabricated from the scalable routes.
MeV proton and neutron damage effects on deep-ultraviolet light-emitting diodes
Authors: Li Jian-Sian , Chiang Chao-Ching , Wan Hsiao-Hsuan , Kim Jihyun , Barke Simon , Wass Peter , Ren Fan , Conklin John W. , Pearton S. J.
Published: August 2024

270 nm deep-ultraviolet AlGaN light-emitting diodes were irradiated with either neutrons or 15 MeV protons. Neutrons produced via charge-exchange reactions of 9Be with protons exhibited energy ranges from 0 to 33 MeV, with an average energy of approximately 9.8 MeV. The fluences ranged from 1.1 × 1014 to 2.2 × 1014 neutrons cm−2 and 1013 or 1014 protons cm−2. Two primary degradation modes were observed: increased trap-assisted tunneling, indicated by an initial reduction in turn-on voltage, and a decrease in carrier concentration, shown by reduced forward current due to deep state formation. For instance, 15 MeV proton irradiation resulted in more than an order of magnitude reduction in reverse current at a fluence of 1014 ions cm−2. The decrease in subthreshold leakage current at higher fluences of neutrons and protons is attributed to defect-induced carrier trapping, thereby reducing layer conductivity across the p-n junction. Emission intensity decreased with fluence for both protons and neutrons, without a measurable increase in midgap emission. The nonlinear degradation in current and light output with fluence suggests strong dynamic recombination of defects during irradiation of high aluminum alloys.
Tuning microstructural and oxidative characteristics of direct current- and high-power pulsed magnetron sputtered MoSi2-based thin films
Authors: Richter Sophie , Bahr Ahmed , Kutrowatz Philip , Wojcik Tomasz , Kolozsvári Szilárd , Polcik Peter , Jerg Carmen , Ramm Jürgen , Riedl Helmut
Published: August 2024

A comparative study on nonreactively direct current magnetron sputtered (DCMS) and high-power pulsed magnetron sputtered (HPPMS) MoSi2-based coatings has been implemented with the objective of advancing the knowledge on the growth conditions and oxidation resistance of MoSi2 thin films. The energy supplied during the growth process (i.e., deposition temperature and ionization degree) exerts a significant influence on the phase formation and morphology. At 200 °C, highly dense but x-ray amorphous films are prevalent, whereas an increase up to 400 °C leads to dense and fine-columnar structured hexagonal MoSi2 films. Increased growth temperatures (≥500 °C for DCMS) and strongly ionized plasma states result in the formation of dual-phase structures (h-MoSi2 and t-Mo5Si3), accompanied by slightly underdense but strongly columnar grains. The MoSi1.92 HPPMS film (1000 Hz, 10% duty cycle) grown at 500 °C exhibits the maximum hardness of 22.8 GPa and an elastic modulus of approximately 400 GPa. In long-term oxidation tests conducted at 600, 850, and 1200 °C (up to 100 h), all MoSi2-based films exhibited a temperature-dependent scale formation. Up to 850 °C, the formation of a continuous, dense protective scale is disrupted by the competing growth of MoOx and SiOx. At temperatures exceeding 1200 °C, all MoSi2-based coatings analyzed demonstrate exceptional oxidation resistance, resulting in the formation of a continuous, dense SiO2 scale. At 1500 °C for 30 min, the initially slightly underdense and dual-phased MoSi1.92 coating achieved a scale thickness of only 670 nm, thereby demonstrating the exceptional oxidation resistance capabilities of HPPMS-grown MoSi2-based coatings.
Effects of Velocity Loss During Bench-Press Training With Light Relative Loads
Authors: Rodiles-Guerrero Luis , Sánchez-Valdepeñas Juan , Cornejo-Daza Pedro Jesús , Páez-Maldonado José , Cano-Castillo Clara , Bachero-Mena Beatriz , Sánchez-Moreno Miguel , Pareja-Blanco Fernando
Published: August 2024

Purpose: This study explored the effects of 4 bench-press (BP) training programs with different velocity-loss (VL) thresholds (0%, 15%, 25%, and 50%) on strength gains and neuromuscular adaptations. Methods: Forty-six resistance-trained men (22.8 [4.4] y) were randomly assigned into 4 groups that differed in the VL allowed within the set: 0% (VL0), 15% (VL15), 25% (VL25), and 50% (VL50). Training loads (40%–55% 1-repetition maximum), frequency (2 sessions/wk), number of sets (3), and interset recovery (4 min) were identical for all groups. Participants completed the following tests before and after an 8-week (16-session) BP training program: (1) maximal isometric test, (2) progressive loading test, and (3) fatigue test in the BP exercise. During all tests, triceps brachii muscle electromyography was assessed. Results: After completing the resistance-training program, no significant group × time interactions were noticed for isometric and dynamic BP strength variables. The dose–response relationship exhibited an inverted U-shaped relationship pattern, with VL25 showing the greatest effect sizes for almost all strength variables analyzed. The total number of repetitions performed during the training program increased as the VL magnitude increased. Conclusions: The group that trained with high VL threshold (50%), which performed a total of 876 repetitions, did not experience additional strength gains compared with those experienced by the 0%, 15%, and 25% of VL groups, which performed significantly fewer repetitions (48, 357, and 547, respectively). These findings suggest that when light loads (40%–55% 1-repetition maximum) are used, low and moderate VL thresholds (0%–25%) provide a higher training efficiency.
Effects of 6-Week Weighted-Jump-Squat Training With and Without Eccentric Load Reduction on Explosive Performance
Authors: Yi Baoyi , Zhang Liang , Zhang Conghui , Huang Tian , Wang Yang , Zhao Xinrong , Yan Bing , Girard Olivier
Published: August 2024

Purpose: To compare the effects of 6-week barbell weighted-jump-squat (WJS) training with and without eccentric load reduction on explosive performance. Methods: Twenty well-trained male athletes were randomly assigned to either an experimental group (n = 10) or a control group (n = 10). Participants completed 12 WJS training sessions (6 sets of 5 repetitions of barbell back squat at 30% of 1-repetition maximum [1RM]) twice a week over a 6-week period. While the control group used 0% eccentric loading (ie, traditional WJS), the experimental group utilized a 50% eccentric loading reduction with a mechanical braking unit (ie, eccentric load set at 15% of 1RM). Performance assessments, including countermovement jump, 20-m sprint, standing long jump, and 1RM barbell back squat, were conducted both before (pretests) and after (posttests) the intervention. Results: Both the experimental group and the control group demonstrated a significant increase in countermovement-jump height (+6.4% [4.0%] vs +4.9% [5.7%]; P < .001) and peak power output (+2.3% [2.7%] vs +1.9% [5.1%]; P = .017), faster 20-m sprint times (+9.4% [4.8%] vs +9.2% [5.5%]; P < .001), longer standing long jump (+3.1% [2.5%] vs +3.0% [3.3%]; P < .001), and higher 1RM back squat (+6.4% [4.0%] vs +4.9% [5.7%]; P < .001) from pretests to posttests. However, there was no significant condition × time interaction for any variable (all P ≥ .294). Conclusions: Both WJS training methods, with and without load reduction in the eccentric phase, effectively enhance explosive performance. Nevertheless, athletes in later stages of injury rehabilitation or intense training may find reducing eccentric load a more tolerable strategy for achieving similar performance gains compared with traditional isoinertial loading.
Chronobiological Insights in Plyometric Jump Training: Optimizing Sport-Performance Adaptations for Volleyball Players
Authors: Zhu Meizhen , Cui Zhenghe
Published: August 2024

Purpose: The objective of this study was to investigate the effects of morning versus evening plyometric training (PT) on performance adaptations in male volleyball players. Methods: A total of 30 collegiate national-level young male volleyball players (age = 21.9 [2.1]; height = 186 [4.1]; body mass = 82.4 [4.6]) were randomly divided into 3 groups: morning PT (MPT), evening PT (EPT), and an active control group, each group consisting of 10 subjects. The players engaged in PT sessions twice weekly for a period of 6 weeks. The evaluation of biomotor abilities such as countermovement vertical jump, standing long jump, spike jump, block jump, 10-m sprint, T-test, sit and reach, and Y-balance test took place in the morning and evening before and after the intervention. Results: Both the MPT and EPT groups indicated significant (P < .05) improvements in all biomotor abilities from pretraining to posttraining during both the morning and evening testing sessions. Furthermore, the MPT group displayed greater adaptive responses in the vertical jump (P = .001), standing long jump (P = .023), and Y-balance test (P ≤ .01) compared to the EPT group. Time-of-day fluctuations were the same between the MPT and EPT groups at the pretest. Conversely, EPT demonstrated significantly more daytime variations than MPT in the jump, sprint, and balance tests at postintervention (P < .05). Conclusion: Engaging in PT at specific times of the day has a significant impact on biomotor ability adaptations, with a focus on morning being more favorable than the evening for achieving greater gains in jump and balance performance of volleyball players.