bluuebunny/crossref_metadata_2025 huggingface dataset:
Knowledge, attitude, and practice of frailty management among clinical nurses: A cross-sectional study
Authors: huang Xueyan , Zhou Haifang , Feng Ying , Li Mengchi , Wang Rui , Ge Fang , Lu Lumeng , Chen Jian’ao , Jiang Wenhui
Published: November 2024

Background
Frailty is a leading risk factor of falls, incapacitation, functional decline, and even death in aging populations globally. Clinical nurses play pivotal roles in screening, prevention, and intervention to reverse or slow the progression of frailty. Therefore, it is essential to clarify knowledge of, attitudes towards, and practices of frailty management among clinical nurses.
Methods
Questionnaire surveys were sent electronically to clinical nurses in a tertiary hospital in Zhejiang Province, China. The survey instruments included a questionnaire inquiring about the knowledge, attitudes, and practices of nurses in terms of frailty management, a demographic data form, and a self-designed frailty educational information questionnaire. Data were analyzed by descriptive statistics, univariate analysis, multiple linear regression, and structural equation modeling.The STROBE checklist was used for the reporting of this study.
Results
Of 524 nurses, Only 37.2% were rated as good in terms of knowledge, attitude, and practice of frailty management, while 55.7% were rated as moderate. Among them, the proportion of nurses with good knowledge (10.30%) and practical skills (13.4%) is much lower than their attitude (67.82%). Structural equation modeling found that knowledge and attitudes were related to frailty management practices, with significant associations between knowledge and attitudes. Attitude exerted a partial mediating effect on the pathway from knowledge to practice, accounting for 20.03% of the total effect. Multiple linear regression analysis showed that age, organizational support, familiarity with relevant guidelines, familiar with the term frailty, and department all had a significant effect on the total score.
Conclusions
Despite inadequate knowledge and limited experience in frailty management, clinical nurses’ attitudes towards frailty management were positive, indicating potential for improvement. The model was useful to explain practices in frailty management, thereby providing a theoretical basis for development of targeted training programs.
Clinical trial number:
not applicable.
Spatiotemporal Relationship between Air Pollution and Upper Respiratory Tract Infection Cases Among Children Under Five: A Case Study of Nakuru County, Kenya (2020-2022)
Authors: Kipterer John Kapoi , Sowe Alieu , Boitt Mark K , Mundia Charles N
Published: November 2024

Air pollution seriously threatens respiratory health, particularly for children under five. The majority of air pollution-related fatalities occur in low- and middle-income countries, with Africa bearing a significant burden. The rapid urbanization, vehicle emissions, and inadequate waste management in Kenya have led to a surge in respiratory illnesses, such as Upper Respiratory Tract Infections (URTI) in Nakuru County. To address this pressing issue, this study explored the use of remote sensing data to analyze pollutant levels (CO, NO2, SO2, and PM2.5-AOD) and URTI cases from 2020 to 2022. This research aimed to uncover the correlation between air pollution levels and respiratory health outcomes, emphasizing the urgent need for action.
Health facility data from KHIS and WHO were mapped using ArcGIS, with a 10 km buffer for spatial analysis. Google Earth Engine extracted and processed pollutant data (CO, NO2, SO2, PM2.5). Statistical analysis was conducted using Pearson, Spearman, and Mann-Kendall tests in R to analyze the correlation between pollutants and URTI cases, providing insights into temporal trends and spatial distributions of contaminants relative to health outcomes.
The spatial analysis showed low and moderately distributed CO concentrations, consistent levels of PM2.5-AOD, and a peak in URTI cases from May 2021 to February 2022, with no clear evident seasonal correlation with NO2 levels. SO2 levels remained low, and CO variations showed no seasonal association with URTI. AOD was lower in early 2020, 2021, and January 2022 without affecting the URTI patterns.
The correlation analysis revealed weak positive relationships between URTI and pollutant levels, with Pearson coefficients of 0.042 and 0.002, respectively, and even weaker relationships for PM2.5-AOD. This suggests that other unmeasured factors might influence URTI incidences or that the analysis needed to capture the impact of pollutants fully. However, these findings are crucial as they highlight the need for further exploration of indoor air pollution, socioeconomic status, nutrition, and genetic predisposition to gain a comprehensive understanding of this issue. They have the potential to significantly impact future research and policy decisions in this area.
Risks and Complications of Monozygotic Triplet Pregnancy Following Single Blastocyst Transfer: Insights from a Case Report and Future Directions.
Authors: Upadhyay Divyesh , Halaby Rajia Al , Anandt Sudha , Albuz Firas , Almekosh Rawan , Peramo Braulio
Published: November 2024

Background
This case report explores the rare occurrence of monozygotic triplet pregnancies resulting from a single blastocyst transfer in Assisted Reproductive Technology (ART). The novelty lies in documenting this unusual outcome, which provides valuable insights into the potential for zygotic splitting and its implications for reproductive practices.
Case Presentation
The patient, a woman with diminished ovarian reserve, underwent in vitro fertilization with intracytoplasmic sperm injection (IVF-ICSI) and Preimplantation Genetic Testing for Aneuploidy (PGT-A). The testing identified one euploid and one aneuploid embryo. With informed consent, a single euploid frozen-thawed embryo was transferred. The pregnancy resulted in the development of monozygotic triplets, as confirmed by the presence of three yolk sacs and fetal poles. Unfortunately, the pregnancy ended in a spontaneous miscarriage at the 10th week of gestation.
Conclusion
The development of monozygotic triplets from a single embryo transfer underscores the unpredictable nature of ART and the potential for rare outcomes such as zygotic splitting. This case highlights the need for heightened awareness, early detection, and proactive management of such pregnancies to address associated risks. Further research is needed to better understand the mechanisms behind zygotic splitting in ART procedures and to improve clinical outcomes.
The Experience of Parents of Autistic Children with Pathological Demand Avoidance: An Interpretative Phenomenological Analysis
Authors: Curtis Sam , Izett Elizabeth
Published: November 2024

Purpose: Emergent research literature has identified emotional and behavioural challenges for autistic children with pathological demand avoidance (PDA). However, understanding of their parents’ experience is limited. This study aimed to explore the experience of parents of autistic children with PDA. Methods: Semi-structured interviews were completed with ten parents of autistic children with PDA, aged between 5 and 11 years. To explore what meaning participants gave to their lived experience, an interpretative phenomenological analysis was conducted on interview data. Results: Four main themes were developed from the IPA data analysis; the benefit of a shared understanding about PDA to the parents and their PDA children, the power of PDA and the impact on families, the emotional experience of parents, and the various ways in which they coped. Conclusion: The need for further recognition and understanding about PDA is emphasised through recommendations for future research. As is the need for flexible, informed, and appropriate support for PDA children and their families.
Oncoplastic Breast Reconstruction with Single-Port Laparoscopically Harvested Omental Flap: Insights from a Ten-Year Tertiary Center Experience
Authors: Yoon Kyung-Hwak , Ahn Sang-Hoon , Shin Hee-Chul , Koh Hyoung Won , Park Joseph Kyu-Hyung , Myung Yujin , Jeong Jae Hoon , Heo Chan Yeong , Kim Eun-Kyu
Published: November 2024

Purpose
To evaluate the 10-year functional and oncological outcomes of single-port laparoscopically harvested omental flap (SLOF) for immediate breast reconstruction after breast cancer surgery. The technical feasibility and oncologic safety of breast reconstruction using a laparoscopically harvested omental flap remain controversial.
Methods
We examined 236 patients with breast cancer (including 2 patients with malignant phyllodes tumors) who underwent nipple-sparing mastectomy or breast-conserving surgery followed by immediate SLOF reconstruction between February 2015 and March 2024 at our institution. Short- and long-term outcomes were assessed. Cosmetic outcomes were evaluated using a three-panel assessment and the Seoul Breast Esthetic Scoring Tool and compared with those of a matched cohort of patients who underwent transverse rectus abdominis myocutaneous (TRAM) flap breast reconstruction.
Results
The rate of clinically significant complications of Clavien-Dindo grade IIIa or greater was 3.8% (9/236). Two patients with flap failure required flap removal and conversion to other reconstruction procedures. The cosmetic satisfaction rates were 82.5% and 76.4% in the SLOF and TRAM groups, respectively (P = 0.467). Over a median 59-month follow-up, the local, regional, and systemic recurrence rates were 3%, 2.1%, and 3%, respectively. All patients underwent annual screening for gastric cancer via esophagogastroduodenoscopy, and there were no cases of delayed flap removal due to gastrectomy.
Conclusions
Oncoplastic breast reconstruction using SLOF is safe and feasible. The natural contour and texture of the reconstructed breast and the nearly invisible scar at the abdominal single-port incision provide excellent cosmetic outcomes that are superior to those of other reconstruction methods.
The mixed effects of recent cover crop adoption on U.S. cropland productivity
Authors: Lobell David , Tommaso Stephania di , Zhou Qu , Ma Yuchi , Specht James , Guan Kaiyu
Published: November 2024

Farmers in the United States have rapidly expanded the use of cover crops (CC), with national CC area nearly doubling since 2012. Despite many benefits that motivate public subsidies, questions remain about potential downsides. Using satellite observations from over 100,000 fields, half of which recently adopted CC, we demonstrate that CC led to: (i) declines in average yields for corn and soybean, by ~3% and ~2%, respectively; (ii) delays in sowing of corn (4 days) and soybean (3 days); (iii) reduced damages in the wet spring of 2019, with CC fields only half as likely to experience prevented planting as non-CC fields. CC appears to reduce important aspects of farmer risk in wet conditions but increase them in dry conditions. Timely planting of the cash crop deserves emphasis moving forward, as we show eliminating sowing delays would reduce yield penalties by roughly 50% for corn and 90% for soybean.
A Case of Cutaneous Cryptococcosis and Literature Review
Authors: Wu Shurui , Zhao Pei , Lin Biwen , Zhang Xiaoning , Ye Kun , Li Chengxin , Song Cuihao
Published: November 2024

Background When a patient presents with painful skin ulcers accompanied by purulent discharge and there is a possibility of immune deficiency, the potential for opportunistic pathogen infection should be considered.
Case Presentation This report presents a case of a skin cryptococcal infection in a 68-year-old female patient who had been on long-term oral ruxolitinib due to myelofibrosis. The skin lesions were characterized by red plaques on the inner side of the right upper arm, accompanied by painful ulcers that had persisted for 9 months. Following an incision and drainage procedure locally, there was continuous purulent exudate that did not heal. Pathological examination indicated diffuse lymphocytic infiltration in the dermis, with a small number of neutrophils, and PAS staining was positive. Cultures of the purulent discharge revealed Cryptococcus neoformans in full view, with positive India ink staining. Serum cryptococcal antigen testing was positive, and after antifungal treatment and daily wound irrigation, the lesions healed.
Conclusions This article briefly introduces the diagnosis and treatment process of the patient in this case and further analyzes the possible causes. Our literature review reveals that skin cryptococcosis lesions are typically non-specific, and clinical manifestations alone are insufficient for a definitive diagnosis. It is essential to maintain clinical vigilance and combine tissue pathology and microbiological examinations.
Examining the Feasibility and Preliminary Effects of Eyes-Open and Eyes-Closed Backward Treadmill Training on Balance, Mobility, and Fear of Falling in Sub-Acute Stroke Survivors: A Pilot Randomized Clinical Trial
Authors: Pathan Nawaj Mehtab , Saxena Rahul , Kumar Chandan
Published: November 2024

Introduction: Gait impairment among stroke survivors is a prevalent and significant issue that necessitates appropriate rehabilitation interventions to address multiple factors such as muscle strength, balance, and coordination. One recommended approach for improving gait function is physical therapy, which helps to improve strength, balance, and coordination by reducing muscle weakness, spasticity, and tone. Other interventions that have demonstrated efficacy in enhancing gait function and mobility among stroke survivors include task-specific, high-velocity gait training. The effects of backward treadmill training were comparable to or superior to those of forward treadmill training in improving balance, gait speed, and stride length. Backward treadmill training can be considered as a potential rehabilitation intervention for stroke survivors with gait impairments.
Methods: This study will be a two-arm, double-blinded, 4-week pilot, randomised clinical trial involving 4-week interventions & 2 weeks follow-up. Forty subacute stroke survivors will be recruited from a tertiary care hospital in India. The study participants will be randomly assigned to either the eyes-open backward treadmill training group EOBT(n=20) or the eyes-closed backward treadmill ECBT training group (n=20). The participants in both groups will receive 4-week interventions and standard care. Standard care consists of self-management exercises printed in a booklet. The primary outcomes will include a series of feasibility assessments of the study protocols about the study’s methodological procedures, including subject recruitment and follow-up processes, completion of study protocols, and feasibility acceptability and safety of the intervention such as balance, gait, and fear of fall, which will be evaluated using the Berg Balance Scale, Timed Up and Go Test, and Fall Efficacy Scale.
Ethics and Dissemination: Ethical approval was obtained from the Institutional Ethical Committee of Sharda University (Ref No-SU/SMS&R/76-A/2022/73). The research results will be presented at conferences and disseminated through scientific journals subject to peer review.
Trial Registration Number: -CTRI/2023/08/056653.
Dual Natural Enzyme-Tuned Biomineralized Nanoflowers for Boosting Cascade Catalytic Antibacterial Therapy and Relieving Inflammation
Authors: Zhang Hanyu , Hao Meng , Dong Xiao , Liang Gemeng , Zou Jinshuo , Li Yongxin , Xie Peitao
Published: November 2024

The development of the non-antibiotic agents that clinically safe remains a huge challenge in combating bacterial infections. Herein, we report the construction of dual natural enzymes bromelain (Bro) and glucose oxidase (Gox)-based peroxidase-like nanoflowers through copper phosphate biomineralization for synergistic antibacterial/anti-inflammatory therapy. The hybrid nanoflowers firstly exert the Gox activity for catalyzing the oxidation of glucose to produce H2O2, which is subsequently converted into highly reactive ·OH through their peroxidase-like activity. This cascade enzymatic activity endows nanoflowers with excellent antibacterial efficiencies, inhibiting the growth of Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) by 99% without the addition of exogenous H2O2, thus greatly reducing toxic side effects. Meanwhile, the nanoflowers downregulate the secretion of pro-inflammatory cytokines and inhibit the inflammatory response through the release of Bro, significantly accelerate the healing of bacteria-infected wounds. Besides, the nanoflowers utilize the biomolecules and endogenous metal species as building blocks, together with a green and simple synthesis method, guaranteeing their biosafety in practical applications. Overall, the unparalleled biocompatibility and robust antibacterial/anti-inflammatory ability make the nanoflowers a highly promising candidate for the treatment of bacterial infections in future clinical applications.
Unraveling the competition between charge and energy transfer in 0D/2D nanographene-graphene heterojunctions
Authors: Wlazło Mateusz , Langer Michal , Semchuk Oleksandr Y. , Osella Silvio
Published: November 2024

The charge and energy transfer processes in photoexcited 0D/2D donor/graphene heterojunctions occur through multiple different pathways. A donor deexcitation event occurring in the most prevalent Förster energy transfer mechanism (strongly favored over Dexter transfer in van der Waals heterojunctions) forbids the charge transfer from occurring, thus creating a competition between the two processes. By applying a robust computational approach, we describe the two processes from first principles, and quantify their rates using Förster and Marcus theories. We consider nanojunctions where the donor are nanographenes with varying size and symmetry, and discern important trends, e.g. the symmetry-induced quenching, or the enhancement due to increased size. We find that heterojunctions where nanographenes do not have a center of symmetry show decreased photoinduced hole and energy transfer rates, which can then be recovered by increasing the delocalization length, whereas for centrosymmetric nanographenes both hole and energy transfer processes are enhanced. However, the hole transfer rate dominates over the energy transfer process, providing a new computation-driven design principle for obtaining a high-charge transfer junction with minimized contribution of the competing energy transfer.
Estimating the nutritional value of an aerobic digester waste by vertical agriculture system (hydroponics)
Authors: Ghai Manan Kaur , khatri Annu , Seth Kunal , Thakur Indu Shekhar
Published: November 2024

Soilless cultivation (Hydroponics) has emerged as a potential technique which is expeditiously acquiring the interest of a wide range of researchers and scientists all around the globe. Loss of arable land, soil degradation, water shortages, biodiversity loss, and climate change are all having negative consequences for a key agricultural industry. The two most essential criteria impacting crop production in hydroponics are the growth media (substrates). The study is helpful in determining the appropriate growing media and nutrient solution concentration for commercial cultivation of commercial plants like Lactuca sativa, Spinacia oleracea, Brassica rapa and Coriandrum sativum are grown hydroponically. The response of plant to different growing media (nutrient media) was examined and analysed in detail in this study. The macronutrient and micronutrient analysis were done and evaluated. However, our findings must be interpreted in light of a few limitations in the research design and implementation. In future it might be possible due to de-contamination of the toxic compounds from the aerobic digester waste water, the quality and quantity of the plant might improve. Utilisation of nano-nutrients can be done which can provide high stability in the nutrient solution. Development of photo tubes can be done to enhance photosynthesis and also to work out the cost.
Exploring the effect of pore shape on mechanical properties of porous rock-like materials under uniaxial compression via DEM
Authors: Fang Chuanfeng , Yu Weijian , Wang Ping , Zhang Zizheng , An Baifu , Wu Genshui , Liu Shunkai , Zhao Tieyong
Published: November 2024

The pore shape is a crucial factor affecting the mechanical properties and failure characteristics of porous rock-like materials. This paper quantitatively analyzes the effects of the angularity and aspect ratio of pores on the mechanical properties of porous rock-like materials under uniaxial compression via the Discrete Element Method (DEM). Numerical models containing pores of various shapes were constructed as Voronoi polygon aggregates to more realistically reflect material fracture. The results indicate that as either angularity or aspect ratio increases, the uniaxial compressive strength and elastic modulus decrease in distinct patterns, while Poisson's ratio remains constant. Additionally, an increase in angularity or aspect ratio not only causes cracks to initiate at the sharp corner and make the crack deviate from the axial loading direction, but also results in an increase in the total length of cracks and the number of fragments. Finally, the evolution of the microstructure, including contact forces and the spatial distribution of stress, was evaluated to investigate the impact of pore shape on microscopic characteristics.
The application of hyperin on tobacco leaf to affect leaf microbial communities and reduce TSNAs in Burley tobacco
Authors: Feng Ji , Yang Chunlei , Yang Ruiwei , Liu Juan , Rao Xiongfei , Qiao Baoming , Qin Guangjiong , Yang Mei , Yang Jinpeng
Published: November 2024

To study the effect of hyperin on the bacterial community diversity and richness on the leaves surface of Burley tobacco, a variety of Burley tobacco ‘Eyan 1’ was used as the research material. On harvesting day, two weeks and four weeks after air-curing, all leaves of the treatment group were sprayed with the hypericin, while all leaves of the control group were sprayed with pure water. The results showed that the application of hyperin could potentially affect the bacterial community diversity and richness on the Burley tobacco leaves. By analyzing the microbial population structure analysis, microbial correlation, and related metabolic pathways, we found that the hyperin can promote the growth of the three genera (Agrobacterium, Stenotrophomonas, and Bacillus) to reduce the TSNAs content of the middle and upper Burley tobacco leaves. The results of this study can provide evidence to study the effect of hyperin on the microbial community and enhance the understanding of the regulation mechanisms of hyperin in Burley tobacco.
Analyzing the Effect of Major Financial Indicators on the Stock Prices of Nepalese Commercial Banks
Authors: Dahal Pramod
Published: November 2024

This research investigates how the price-to-earnings ratio (PE ratio) and other financial indicators influence the market prices of Nepalese commercial banks. It highlights the importance of the market PE ratio in shaping investment decisions among Nepalese investors. The study utilizes multiple regression models to analyze data from five commercial banks listed on the Nepal Stock Exchange, covering 35 yearly observations from the fiscal years 2015/16 to 2021/22. The analysis reveals a significant positive relationship between the market prices of these banks and their PE ratios and book values. Other indicators, such as the dividend rate, earnings yield, and market-to-book value ratio, also show positive relationships, though their significance diminishes in certain cases. However, the study's generalizability may be limited due to the small sample size and the focus on a few financial measures specific to commercial banks. Despite this, the research offers valuable insights, particularly emphasizing the PE ratio as a key factor that Nepalese investors consider in their investment decisions. The findings are expected to be useful for investors, researchers, policymakers, and other stakeholders.
JEL Classification: G11, G12, G21, G41
Microwave pre-stimulation methodology for plant growth promotion
Authors: Suzuki Nobuhiro , Hasegawa Yasuhiko , Kadomatsu Kanae , Yamakawa Kazuha , Sameshima Miori , Ando Atsumi , Horikoshi Satoshi
Published: November 2024

Although positive effects of microwave irradiation on plants have been reported, their underlying mechanisms remain unknown. In this study, we investigated the effects of low microwave irradiation on Arabidopsis thaliana. Interestingly, we found low output (23 wattages) with oscillating condition (not continuous irradiation) promoted plant growth. The microwave irradiation neither raised the plants’ temperature nor induced heat responsive gene expression. Futhermore, overall transcriptome profile in microwave irradiation treated plants were significanly different from heat treated plants, suggesting that growth promotion might be attributed to non-thermal effects of microwave. Transcriptome and metabolome analysis indicated that microwave irradiation altered circadian clock as well as hormonal response especially in auxin and gibberellin, which promoted plant growth by inducing amino acid biosynthesis and stress tolerance, and reducing cell wall thickness. This finding potentially contribute to develop new approach to increase food production through accelerating crop yield in environmentally friendly way.
Enhanced surface-groundwater interaction modeling in the middle and lower reaches of the Songhua River Basin using a coupled SWAT-MODFLOW model
Authors: Yang xiao , Dai Chang-Lei , Jing Jian-yu , Liu Geng-wei , Ru Qing , Li Jia-jun , Liu Peixian
Published: November 2024

The management of groundwater resources and the rehabilitation of groundwater levels in the middle and lower portions of the Songhua River basin have consistently garnered significant attention in our country. The SWAT-MODLFOW model, developed on the QSWATMOD2 platform, was calibrated and validated utilizing river runoff and groundwater observation data to precisely illustrate the transformation relationship across various spatial and temporal scales in the middle and lower reaches of the Songhua River basin, characterized by numerous agricultural and irrigation zones with frequent surface water conversion. The water cycle process in the middle and lower sections of the Songhua River basin is simulated and studied based on this foundation.The results show: (1) The SWAT-MODLFOW coupling model has a good simulation effect, and the simulation effect of menstrual flow in the periodic and verification periods is R2≥0.86, NSE≥0.87, R2≥0.76, NSE≥0.77, respectively. The simulated groundwater level and the actual error value are within 0.6m, and the R2 in the periodic and verification periods are 0.97 and 0.98, respectively. The simulation results of the model are satisfactory and meet the requirements of scientific research. (2) The groundwater in the study area generally decreases in the direction of west-north to northeast, and in the direction of east-south to north, and the groundwater level is affected by precipitation. Jiamusi, Fujin and Tongjiang, three major cities in the study area, are selected for characteristic study, and the lag time of their groundwater level to precipitation is about 10.56d, 10.58d and 3.15d. (3) The river channels of surface water recharge groundwater occupy 41.75% of the total length of Jiamusi - Tongjiang section of Songhua River, and the annual average recharge accounts for 50.84% of the total exchange water; On the seasonal scale, the maximum recharge value of each river section appeared in August, and the minimum recharge value appeared in April. On an annual scale, the maximum recharge occurred in 2009 and the minimum in 2014. The supply of groundwater to surface water fluctuates obviously, with seasonal variation ranging from -52% to 55% and inter-annual variation ranging from -35% to 52%.
Research on Planning and Construction Strategies for Flood Control Projects: A Case Study of the Erlongtao River Section of the Heilongjiang River
Authors: chen yuxiu , Zhang Liyin , Zhang Ge , Sang Zijie
Published: November 2024

Due to the combined effects of many factors, flood disasters are becoming increasingly serious worldwide, resulting in increasingly frequent river floods. This situation has severely disrupted the ecological balance near riverbanks and has had a great negative impact on the normal production and life of residents. Therefore, certain solutions must be adopted to solve the problem of river floods. This study takes the section of the Erlongtao River in Heilongjiang Province, China, as the research object, presents detailed statistics on the occurrence of floods in this section in recent years, and conducts an in-depth investigation and research on the current status of various flood control projects. In view of the existing problems of the project and the root causes of floods, a comprehensive analysis of the necessity of governance is carried out, and corresponding governance countermeasures and scientific and reasonable design schemes are proposed to improve basic flood control construction and provide a reference case for flood control governance of rivers with the same type of flood control problems in the future.
Experimental study on the influencing factors and pore production law of CO2 huff and puff in tight sandstone reservoirs
Authors: Zhang Rongjun , Zhang Zhe , Sun Jian , Niu Zhihao , Tuo Zhilin , Zhong Xinyu , Zheng Xiaolei
Published: November 2024

In order to determine the influence of different factors on the CO2 huff and puff displacement effect, a CO2 huff and puff experiment was carried out with Chang 6 tight sandstone samples in Ordos Basin as the research object. Combined with nuclear magnetic resonance technology, the influences of injection pressure, cycle numbers and soaking time on the CO2 huff and puff effect were evaluated, and the optimal CO2 huff and puff parameters were optimized. The microscopic degree of crude oil production in different scale pores was quantitatively characterized. The results show that the injection pressure and the cycle numbers have a significant influence on the effect of CO2 huff and puff. With the increase of injection pressure, huff and puff cycle numbers and soaking time, the recovery efficiency increases, but the growth range decreases. When the injection pressure is increased from 6MPa to 12MPa, the degree of pore mobilization in the oil in macro and medium pores (≥ 10ms) increases by 13.0%-22.63%. The recovery efficiency of a single round gradually decreased with the increase of huff and puff rounds. The first cycle of CO2 huff and puff was the main contribution of crude oil recovery. However, the production effect of micro and small pores (< 10ms) was significantly improved after multiple cycle numbers of CO2 huff and puff. When the soaking time increases from 6h to 24h, the recovery efficiency increases by 11.47%-14.93%. After that, the influence of prolonged soaking time on the porosity production degree of cores with different permeability decreases. It is found that medium pores and macro pores are the main contributors to pore mobilization during multiple cycles of CO2 huff and puff.
On Godunov-type finite volume methods for seismic wave propagation
Authors: Camargo Juan Camilo Barrios , Peixoto Pedro da Silva , Silva Felipe Augusto Guedes  da
Published: November 2024

The computational complexity of simulating seismic waves demands continual exploration of more efficient numerical methods. While Finite Volume methods are widely acclaimed for tackling general nonlinear hyperbolic (wave) problems, their application in realistic seismic wave simulation remains uncommon, with rare investigations in the literature. Furthermore, seismic wavefields are influenced by sharp subsurface interfaces frequently encountered in realistic models, which could, in principle, be adequately solved with Finite Volume methods. In this study, we delved into two Finite Volume (FV) methods to assess their efficacy and competitiveness in seismic wave simulations, compared to traditional Finite Difference schemes. We investigated Gudunov-type FV methods: an upwind method called wave propagation algorithm (WPA), and a Central-Upwind type method (CUp).
Our numerical analysis uncovered that these finite volume methods could provide less dispersion (albeit increased dissipation) compared to finite differences for seismic problems characterized by velocity profiles with abrupt transitions in the velocity. However, when applied to more realistic seismic models, finite volume methods yielded unfavorable outcomes compared to finite difference methods, the latter offering lower computational costs and higher accuracy. This highlights that despite the potential advantages of finite volume methods, such as their conservative nature and aptitude for accurately capturing shock waves in specific contexts, our results indicate that they are only advantageous for seismic simulations when unrealistic abrupt transitions are present in the velocity models.
Serum-equivalency Comparison, Detection, and Quantification of Group B Streptococcus Anti-capsular Polysaccharide Antibodies from Dried Blood Spots
Authors: Bolcen Shanna , Patel Palak Y. , Alston Bailey , Li Yikun , Maniatis Panagiotis , Schmidt Donna Giordano , Pavliakova Danka , Southwell Jessica E. , Jia Lily Tao , Gaylord Michelle , Simon Raphael , Monerri Natalie Clare Silmon , Rhodes Julia , Schrag Stephanie , Vishwanathan Sundaram Ajay
Published: November 2024

A standardized multiplex immunoassay (MIA) to quantify group B Streptococcus (GBS) anti-capsular polysaccharide (CPS) IgG serum concentrations was adopted by the Group B streptococcal Assay Standardization (GASTON) consortium as a standardized assay with the most immediate applications for facilitating the licensure of GBS vaccines. However, dried blood spot (DBS) samples offer advantages for immunological studies, including cost-effectiveness, ease of transport, and storage. To determine suitability of DBS as an alternative sample matrix to serum in multiplex immunoassays, a contrived GBS seropositive panel, including matched DBS and serum samples, was prepared using established methods. The calculated geometric mean titers of GBS anti-CPS IgG values by individual serotype were compared using a paired t-test to establish serum equivalency. Geometric mean values for the matched panel were assessed via Deming regression for precision, accuracy, and concordance correlation coefficient (CCC). The initial acceptance criterion was set at 0.95 for CCC. Two additional criteria based on confidence intervals of CCC, slope, and intercept were used to determine the necessity of a serotype-specific conversion factor. The paired t-test p-values were > 0.05 for serum equivalency. For sample matrix concordance, CCC values were > 0.95 and met correlation criteria for all serotypes. Conversion factors were applied to four serotypes (II, III, IV, and V) that did not meet the criteria for slope, intercept, or both. This demonstration of equivalency between DBS and serum supports the hypothesis that DBS is a suitable testing matrix from which to elucidate anti-CPS IgG concentrations in seroepidemiological and vaccine evaluation studies.
Environmentally Friendly Gel Tape Casting of Silicon Nitride Ceramic Substrates with Enhanced Thermal Conductivity
Authors: Liu Yuanfei , Fu Jie , Liu Yuan , Gao Zhengxia , Ma Chengliang
Published: November 2024

With the development of third-generation semiconductors, the heat dissipation problems of electronic packaging systems and the harsh usage environment of high-power devices have put forward higher requirements on the thermal conductivity and mechanical properties of silicon nitride ceramic substrates. As an almost defect-free ceramic forming technology, aqueous gel tape casting technology is very suitable for the forming of ceramic substrate materials because of the high density, low porosity and large forming size of the ceramic flakes produced. However, the existing acrylamide-methylene bisacrylamide (AM-MBAM) gel system has a complicated process, is subject to oxygen depolymerisation and has problems such as neurotoxicity. For this reason, in this study, a non-toxic and environmentally friendly isobutylene-maleic anhydride copolymer (Isobam) gel system was used to prepare silicon nitride ceramic substrates in-situ by combining the methods of gel tape casting and reaction sintering. The amount of additives was adjusted to optimise the rheological properties of the pastes, and the effects of the Si powder nitridation reaction process and different sintering aids on the properties of Si3N4 ceramic substrates were investigated in detail. The results show that the slurries with different additive contents show shear-thinning behaviour and relatively high solid content. Under 0.1 MPa nitrogen atmosphere, Si3N4 has been basically completely generated at 1400°C, and the comprehensive performance of Si3N4 ceramics is optimal with the addition of Y2O3-MgO-ZrO2 sintering additives. The relative density and thermal conductivity were 98.4% and 61.5 W·m− 1·K− 1, respectively, and Si3N4 showed columnar morphology, which effectively improved the hardness, fracture toughness and flexural strength of Si3N4 ceramics, up to 13.39 GPa, 6.9 MPa·m1/2 and 684.5 MPa, respectively.
Microfluidic Passive Valve Regulator for Controlling Flow Rates
Authors: Thabet Hitham
Published: November 2024

In microfluidic applications where cost effectiveness and miniaturization are key, the use of passive microvalve offers significant benefits. This study introduces an innovative passive microfluidic valve design comprising a fluid chamber, a flexible membrane, and a rectangular control chamber, enabling effective flow rate management at exceptionally pressures. The model was created using the 3D photolithography method, and the passive microvalve was evaluated under pressure circumstances that are both constant and time-dependent. In the experiment, the microfluidic passive valve demonstrated a constant flow rate when the pressure ranged from 40 kPa to 70 kPa. This regulator can achieve a consistent delivery flow rate of up to 53 ± 2.5µL/min with deviations under 4.5%, as demonstrated by the testing outcomes. Furthermore, the microfluidic passive valve has demonstrated the capability to maintain a stable liquid flow rate under fluctuating conditions, specifically under square wave pressure variations over time. The suggested microfluidic passive valve device may be used in portable, low-cost Lab-on-a-Chip (LoC) applications to precisely control flow. We anticipate this innovative passive microfluidic valve will work well for regulating fluid flow in systems with broader applications or portable microfluidic devices.
Integrated metabolomic and transcriptomic strategies to reveal adaptive mechanisms in barley plant during germination stage under waterlogging stress
Authors: luan haiye , gao jiajia , qu xin , Yang jnghan , qian xin , xu meng , sun miao , xiao xiao , shen huiquan , zhang yinghu , feng gongneng
Published: November 2024

Waterlogging stress is one of prominent abiotic stresses that has a significant impact on the yield and quality of barley. Seed germination is crucial for seedling establishment and is highly sensitive to waterlogging stress. However, there is a limited understanding of the regulatory mechanisms of gene expression and metabolic processes in barley during the germination stage under waterlogging stress. This study aimed to investigate the metabolome and transcriptome responses in germinating barley seeds under waterlogging stress. The findings of the study revealed that waterlogging stress sharply decreased seedling growth. The tolerant genotype (LLZDM) exhibited higher levels of antioxidase activities and lower malondialdehyde (MDA) content in comparison to the sensitive genotype (NN). In addition, waterlogging induced 86 and 85 differentially expressed metabolites (DEMs) in LLZDM and NN, respectively. Concurrently, transcriptome analysis identified 1776 and 839 differentially expressed genes (DEGs) in LLZDM and NN, respectively. Notably, the expression of genes associated with redox reactions, hormone regulation, and other biological processes were altered in response to waterlogging stress. Furthermore, the integrated transcriptomic and metabolomic analyses revealed that the DEGs and DEMs implicated in mitigating waterlogging stress primarily pertained to the regulation of pyruvate metabolism and flavonoid biosynthesis. Moreover, waterlogging might promote flavonoid biosynthesis by regulating 15 flavonoid-related genes and 10 metabolites. The present research provides deeper insights into overall understanding waterlogging-tolerant mechanisms in barley during the germination process.
Gallium: Assessing the long term future extraction, supply, recycling and price of using WORLD7, in relation to future technology visions in the European Union
Authors: Sverdrup Harald Ulrik , Haraldsson Hördur Valdimar
Published: November 2024

The gallium resources were assessed and used as input to long term simulations using the WORLD7 model. The content of gallium in different mother ores has been estimated to be about 14.7 million ton of gallium. Much of this is not accessible because of low extraction yields, about 610,000 ton gallium appear to be extractable (4%) with present practices. The gallium content in all source metal refining residuals is about 51,000 ton/yr, but only a production of 1,374 ton/yr appear as the maximum with present technology and conditions. The actual gallium production was about 450 ton/yr in 2023. The gallium price is very sensitive to increases in demand, and production is not very likely to be able to rapidly increase. The simulations show that soft gallium scarcity sets in after 2028 and physical scarcity will occur about 2060. Better gallium extraction and recycling yields may push the scarcity date forward to 2100. In the long term, only 60% of the gallium demand to photovoltaic technology can be satisfied. To really improve the situation and prevent scarcity, extractive access, gallium extraction yields and recycling yields must be significantly improved to better than 50%. At present the overall yields are 7-15%. Increasing both extraction yields and recycling yields can reduce the shortage. The long term sustainable extraction is under Business-as-Usual about 300 ton gallium per year, about 67% of the present production. Doubling present extraction and recycling yields may increase this to 460 ton per year. This poses a major challenge to future plans for an energy transition, where under Business-As-Usual (BAU), such a transition will remain a fair fantasy. The four EEA imaginaries, Ecotopia, The Great Decoupling, Unity in Adversity, and Technocracy for the Common Good, offer different policy pathways for managing future gallium scarcity through varying degrees of technological advancement, resource conservation, and avoidance strategy.
A comparative analysis between Piezoelectric and Photovoltaic systems for a better quality of Wireless charging system
Authors: Boukhchana Asma , Mohamed Naoui , Aymen Flah , Habib Kraiem , EL-bayeh Claude Ziad , Blazek Vojtech
Published: November 2024

The number of electric vehicles on the road continues to rise, and finding practical solutions for the charging stage is essential, particularly when traveling long distances. To power the charging coils that enable the EV battery to be charged, we placed piezoelectric generators in this work to recover vibration energy from road disturbances. We also employed solar energy to enable the EV battery to be charged appropriately. Next, using Ansys, we built a 3D model of the transmitting and receiving coils and evaluated their efficiency. Finally, we utilized MATLAB Simulink to evaluate the efficiency of two different energy sources. The results let us compare the two energy sources and show that piezoelectric generators are not suitable for use as the primary energy source due to their poor performance.
Optimal Location and Sizing of Multiple WTs and PVs in Radial Configuration System Using Hybrid Technique
Authors: Samala Rajesh Kumar , Kotapuri Mercy Rosalina , Kothuri Rama Krishna
Published: November 2024

Identification of better sites and capacity of Distributed Generations (DGs) is the greatest issue of power system utilities. In this research an improved idea is presented to solve the optimum power flow problems with uncertainties. This presented idea is the hybridization of Fuzzy with Cuttle Fish Optimization Algorithm (CFOA). The CFOA is roused by the color-altering behavior used by the cuttlefish. The Fuzzy Logic Controller (FLC) has been trained with training datasets and testing time. Firstly, defining and analyzing the multi objective functions like the deviation in voltage, reduction in loss of power and improvement of Voltage Stability Index (VSI). The multi-objectives like minimization of operating cost and reduction in cost factor index by considering voltage constraints. The proposed hybrid algorithm is evaluated on applying on standard IEEE-33 radial configuration test system. To investigate the best placement for multiple Wind Tubines (WTs) and Photo-Voltaic (PVs), four cases are considered. Validation of the proposed methodology is done by comparing it with conventional methods like Ant Lion Optimization (ALO) and Manta Ray Foraging Optimization (MRFO) algorithm. All these methods are executed on MATLAB platform and tested with the various cases.
Design of Unequal Wilkinson Power Divider using Multi-Section Coupled-line for Dual-Band Operation with High Bandwidth Performance
Authors: Sen Sarbani , Sharma Rajesh , Moyra Tamasi
Published: November 2024

A new Wilkinson Power Divider microstrip structure along with design equations has been represented in this paper. The proposed structure replaces the section of a quarter wavelength impedance transformer of a conventional power divider by a multisection coupled line with considerable bandwidth improvement. The new structure is simulated and fabricated using derived design equations for arbitrary selected frequencies 1 GHz and 2.3 GHz with a frequency ratio of 2.3. A high power division ratio of 6.85 is selected based on the available RF resistor 150 Ω. Simulated and measured outputs are presented and a good bandwidth performance is achieved.
Topological Dirac-vortex modes in a three-dimensional photonic topological insulator
Authors: Gao Zhen , Yan Bei , Qi Yingfeng , Wang Ziyao , Meng Yan , Yang Linyun , Zhu Zhenxiao , Chen Jingming , Zhong Yuxin , Cheng Minqi , Xi Xiang
Published: November 2024

Recently, topological Dirac-vortex modes in Kekulé-distorted photonic lattices have attracted broad interest and exhibited promising applications in robust photonic devices such as topological cavities, lasers, and fibers. However, due to the vectorial nature of electromagnetic waves that results in complicated band dispersions and fails the tight-binding model predictions, it is challenging to construct three-dimensional (3D) topological photonic structures with Kekulé distortion and the photonic topological Dirac-vortex modes have thus far been limited to two-dimensional (2D) systems. Here, by directly mapping a 3D Kekulé-distorted tight-binding model in a 3D tight-binding-like photonic crystal exhibiting scalar-wave-like band structures, we theoretically propose and experimentally demonstrate topological Dirac-vortex modes in a 3D photonic topological insulator for the first time. Using microwave near-field measurements, we directly observe robust photonic topological Dirac-vortex modes bound to and propagate along a one-dimensional (1D) Dirac-vortex line defect, matching well with the tight-binding and simulation results. Our work offers an ideal platform to map tight-binding models in 3D topological photonic crystals directly and opens a new avenue for exploiting topological lattice defects to manipulate light in 3D space.