bluuebunny/crossref_metadata_2025 huggingface dataset:
Non-invasive diagnosis of wheat stripe rust progression using hyperspectral reflectance
Authors: Cross James F. , Cobo Nicolas , Drewry Darren T.
Published: September 2024

Wheat stripe rust (WSR), a fungal disease capable of inflicting severe crop loss, threatens most of global wheat production. Breeding for genetic resistance is the primary defense against stripe rust infection. Further development of rust-resistant wheat varieties depends on the ability to accurately and rapidly quantify rust resilience. In this study we demonstrate the ability of visible through shortwave infrared reflectance spectroscopy to effectively provide high-throughput classification of wheat stripe rust severity and identify important spectral regions for classification accuracy. Random forest models were developed using both leaf-level and canopy-level hyperspectral reflectance observations collected across a breeding population that was scored for WSR severity using 10 and 5 severity classes, respectively. The models were able to accurately diagnose scored disease severity class across these fine scoring scales between 45-52% of the time, which improved to 79-96% accuracy when allowing scores to be off-by-one. The canopy-level model demonstrated higher accuracy and distinct spectral characteristics relative to the leaf-level models, pointing to the use of this technology for field-scale monitoring. Leaf-level model performance was strong despite clear variation in scoring conducted between wheat growth stages. Two approaches to reduce predictor and model complexity, principal component dimensionality reduction and backward feature elimination, were applied here. Both approaches demonstrated that model classification skill could remain high while simplifying high-dimensional hyperspectral reflectance predictors, with parsimonious models having approximately 10 unique components or wavebands. Through the use of a high-resolution infection severity scoring methodology this study provides one of the most rigorous tests of the use of hyperspectral reflectance observations for WSR classification. We demonstrate that machine learning in combination with a few carefully-selected wavebands can be leveraged for precision remote monitoring and management of WSR to limit crop damage and to aid in the selection of resilient germplasm in breeding programs.
Colocalising proteins and polysaccharides in plants for cell wall and trafficking studies
Authors: Lampugnani Edwin R. , Persson Staffan , van de Meene Allison M. L.
Published: September 2024

Plant cell walls (PCWs) are intricate structures with complex polysaccharides delivered by distinct trafficking routes. Unravelling the intricate trafficking pathways of polysaccharides and proteins involved in PCW biosynthesis is a crucial first step towards understanding the complexities of plant growth and development. This study investigated the feasibility of employing a multi-modal approach that combines transmission electron microscopy (TEM) with molecular-genetic tagging and antibody labelling techniques to differentiate these pathways at the nanoscale. The genetically encoded electron microscopy (EM) tag APEX2 was fused to Arabidopsis thaliana cellulose synthase 6 (AtCESA6) and Nicotiana alata ARABINAN DEFICIENT LIKE 1 (NaARADL1), and these were transiently expressed in Nicotiana benthamiana leaves. APEX2 localization was then combined with immunolabeling using pectin-specific antibodies (JIM5 and JIM7). Our results demonstrate distinct trafficking patterns for AtCESA6 and NaARADL, with AtCESA6 localized primarily to the plasma membrane and vesicles, while NaARADL1 was found in the trans-Golgi network and cytoplasmic vesicles. Pectin epitopes were observed near the plasma membrane, in Golgi-associated vesicles, and in secretory vesicle clusters (SVCs) with both APEX2 constructs. Notably, JIM7 labelling was found in vesicles adjacent to APEX2-AtCESA6 vesicles, suggesting potential co-trafficking. This integrative approach offers a powerful tool for elucidating the dynamic interactions between PCW components at the nanoscale level. The methodology presented here facilitates the precise mapping of protein and polysaccharide trafficking pathways, advancing our understanding of PCW biosynthesis and providing avenues for future research aimed at engineering plant cell walls for various applications.
Essence of distinction: the ends, ways, and means of China’s military maritime quest
Authors: Erickson Andrew S.
Published: September 2024

The People’s Republic of China (PRC)‘s rapid development of military maritime capabilities, and their harnessing under strong personalist paramount leader Xi Jinping to address ambitious national goals, is one of the most important subjects concerning great power security in the international system today. Understanding the key dynamics is thus inherently important. This article surveys Chinese-language publications, U.S. government analyses, and related research, and applies it to a larger framework that addresses both conceptual and empirical issues, considers comparative cases, and offers suggestions for further examination. Its findings are relevant to scholars and practitioners alike: China’s military maritime power radiates outward, backstopped by a land-based “anti-Navy.” Its Navy focuses on proximate seas—supported by Coast Guard, Maritime Militia, and survey vessel fleets; and extends into the farthest oceans. China’s sea forces and the strategy informing them has become progressively less distinctive with time and distance—trends continuing today. Herein lies one of the greatest strengths, and limitations, of Beijing’s dramatic military maritime development.
The role of affective temperaments in self-care and medication adherence among individuals with bipolar disorder: a moderation analysis
Authors: Visalli Giulia , Longobardi Grazia , Iazzolino Anna Maria , D’Angelo Martina , Stefano Valeria Di , Paribello Pasquale , Steardo Luca , Manchia Mirko , Steardo Luca
Published: September 2024

Background

Affective temperament, defined as the fundamental predisposition from which normal affective states originate or as the constitutional core of personality, play a crucial role in mood disorders, particularly bipolar disorders. Understanding the relationship between temperaments, treatment adherence, and self-care is crucial for effective management and improved clinical results.

Objectives

This study aims to (1) assess the correlation between affective temperaments and treatment adherence, (2) investigate the relationship between affective temperaments and self-care abilities, (3) identify predictors of treatment adherence, and (4) explore the moderating effect of self-care on the relationship between treatment adherence and depressive temperament in individuals with bipolar disorder.

Methods

A cross-sectional study was conducted with 231 individuals diagnosed with bipolar disorder (BD) type I (N=160) and type II (N=71). The participants were evaluated using the following psychometric tools: Temperament Evaluation of Memphis, Pisa, and San Diego (TEMPS) to assess affective temperaments, Personal and Social Performance Scale (PSP) to evaluate social functioning and self-care abilities, and Morisky Medication Adherence Scale (MMAS) to measure treatment adherence. The study involved statistical analyses to examine correlations, identify predictors, and explore moderating effects.

Results

The findings revealed significant correlations between affective temperaments and both treatment adherence and self-care abilities. Specifically, hyperthymic temperament was positively associated with higher treatment adherence, whereas cyclothymic and depressive temperaments were linked to lower adherence. Self-care abilities were found to mediate the relationship between depressive temperament and treatment adherence, suggesting that improved self-care can enhance adherence in individuals with depressive temperament.

Conclusions

Affective temperaments significantly influence treatment adherence and self-care abilities in individuals with bipolar disorder. The mediating role of self-care highlights the importance of developing targeted interventions to improve self-care practices, thereby enhancing treatment adherence and overall well-being. Personalized treatment strategies based on temperament assessments could lead to better clinical outcomes and quality of life for individuals with bipolar disorder.
Health-related quality of life assessed by EQ-5D-5L and its determinants among Chinese adults
Authors: Bai Gengliang , Zhang Jiawen , Chen Yijun , Cao Lejing , Yang Yong , Jiang Chao
Published: September 2024

Background

Due to the rising standard of living and advances in public health and medical care in recent years in China, the health-related quality of life (HRQoL) has been increasingly acknowledged as an important part of health management of adults. This study aimed to analyze the HRQoL of Chinese adults and identify the influencing factors, proposing specific recommendations for improvement.

Methods

A cross-sectional study was conducted among 1,291 selected adults from four provinces spanning different regions in China aged ≥18 years from July 2021 and January 2022. The EuroQol-5D-5L (EQ-5D-5L) was used to conduct the HRQoL survey, and a general questionnaire was administered to collect demographic characteristics, general information, and health behaviors of participants. The health utility value was measured, and one-way analysis of variance was performed. The Tobit regression model was employed to analyze the factors influencing the HRQoL of Chinese adults.

Results

The mean health utility values and visual analog scale scores for adults were 0.9400 ± 0.1197 and 84.09 ± 14.392, respectively. Notably, 60.3% of respondents reported no difficulties in any of the five dimensions of EQ-5D. However, a substantial proportion faced challenges in anxiety/depression (27%) and pain/discomfort (26.2%). Tobit regression model revealed that age, marital status, educational level, diet, sleep, mental state, mood, and chronic diseases significantly impact the HRQoL of Chinese adults.

Conclusion

The HRQoL among Chinese adults is generally satisfactory, but pay particular attention on areas such as pain, psychological anxiety, chronic diseases, and negative emotions is needed. The factors such as stress associated with marriage and the demands of high-skilled occupations might influence the overall health of the population. According to our findings, public health strategies to improve HRQoL should be developed to promote relatively healthy environments and lifestyles for older adults. Moreover, proactive measures are crucial for mitigating the potential health impacts associated with marital stress and high-skilled employment.
Non-biological factors associated with postpartum depression among women in Shenzhen: a case-control study
Authors: He Jiangshan , Li Yang , Chen Ling , Zhang Ying
Published: September 2024

Background

Postpartum depression (PPD) presents a significant public health challenge. While PPD’s impact extends from maternal health to child development, cultural stigma and a lack of public awareness, particularly in developing countries, contribute to its underestimation and under diagnosed. This study investigated the non-biological associated factors for PPD in Shenzhen city due to its unique socioeconomic landscape, where rapid urbanization and migrant influx could uniquely impact maternal mental health. By identifying local PPD determinants, the research aimed to contribute to targeted mental health interventions in the region.

Method

Data were collected from May to December 2019 at the Luohu Maternal and Child Health Medical Center, Shenzhen. Inclusion criteria were postpartum women without psychiatric histories who live within the locality. The Chinese Edinburgh Postnatal Depression Scale was utilized to confirm PPD diagnosis. Participant information including demographics, economic status and postnatal factors were collected via structured questionnaires. Statistical analyses of t-tests, Wilcoxon rank-sum tests, chi-square tests, and logistic regression, were performed using SPSS 20.0, with significance set at p ≤ 0.05.

Results

The study included 430 healthy mothers and 73 PPD mothers. Several factors were found to significantly influence the onset of PPD (p < 0.05): age (OR = 0.921, 95% CI: 0.864–0.981); living with in-laws (OR = 2.133, 95% CI: 1.108–4.106); bottle feeding (OR = 3.757, 95% CI: 1.567–9.006); prenatal depression (OR = 3.515, 95% CI: 1.61–7.675); prenatal anxiety (OR = 6.072, 95% CI: 3.209–11.49); and adverse life events during pregnancy (OR = 3.287, 95% CI: 1.165–9.269). Other factors were not found to have a significant effect.

Conclusion

Our study found that in the developed city of Shenzhen in Southern China, living with in-laws, exclusive bottle feeding, prenatal anxiety, depression, and adverse life events are non-biological associated factors for postpartum depression. The findings emphasize the importance of considering a range of factors when addressing maternal mental health within a specific local regions. It calls for targeted interventions or prevention program that take into considering the specific cultural, social, and individual factors.
National survey questionnaire on the diagnosis and treatment status of Helicobacter pylori in peptic ulcer bleeding disease
Authors: Jiang Zongdan , Ding Yaokun , Li Chao , Zhang Zhenyu
Published: September 2024

Background and objective

The Maastricht VI/Florence Consensus and Chinese National Consensus Report provide comprehensive guidelines for treating Helicobacter pylori infection. This study aimed to assess physicians' understanding of and adherence to this consensus in different hospitals.

Methods

Chinese medical staff attending gastrointestinal conferences across various regions were selected for this study. The questionnaire included: 1. the number of patients with peptic ulcer bleeding in hospitals of different levels annually and the diagnostic methods used for H. pylori; 2. whether routine H. pylori examination was conducted and the specific methods employed; and 3. Treatment plans for H. pylori eradication; 4. The mean follow-up duration after treatment 5. Plans for re-eradication in cases of H. pylori treatment failure.

Results

Across all levels of Chinese hospitals, the urea breath test was the most commonly used method for detecting H. pylori infection. Most primary (81.53%), secondary (89.49%), and tertiary (91.42%) centers opted for a 14-day quadruple regimen. The preferred antibiotic regimen at all hospital levels was amoxicillin+clarithromycin, with rates of 63.69, 58.08, and 59.27% in the primary, secondary, and tertiary hospitals, respectively. The rates of H. pylori re-examination were 68.15, 87.07, and 87.46% in the primary, secondary, and tertiary hospitals. If H. pylori eradication failed, hospitals at different levels choose to replace the initial plan.

Conclusion

There is a need for an enhanced understanding of and adherence to guidelines for H. pylori among physicians in hospitals at all levels.
The association between accelerated biological aging and the risk of osteoarthritis: a cross-sectional study
Authors: He Qiang , Luo Hua , Mei Jie , Wang Zhen , Sun Xin , Wang Ling , Xie Chengxin
Published: September 2024

Background

Biological age (BA) offers an effective assessment of true aging state. The progression of Osteoarthritis (OA) is closely associated with an increase in chronological age, the correlation between BA and OA has not been fully elucidated.

Methods

This study analyzed data from the National Health and Nutrition Examination Survey (NHANES) 2005–2018. Thirteen commonly used clinical traits were employed to calculate two measures of BA: the Klemera-Doubal method age (KDM-Age) and phenotypic age (Pheno-Age). The residuals of the regression of these ages based on chronological age were calculated as KDM-Age or Pheno-Age acceleration, respectively. OA was determined through self-reported prior diagnoses. The prevalence of OA across different quartiles of BA was compared using weighted chi-square tests and linear trend tests. The association between BA and OA was assessed using weighted multivariate logistic regression models.

Results

A total of 30,547 participants aged ≥20 years were included in this study, 3,922 (14%) were diagnosed with OA. Participants with OA exhibited higher chronological age, KDM-Age, Pheno-Age, KDM-Age advance, and Pheno-Age advance compared to those without OA (p < 0.001). The prevalence of OA significantly increased with higher quartiles of KDM-Age advance and Pheno-Age advance (P for trend < 0.001). In the fully adjusted model, compared to the lowest quartile (Q1) of KDM-Age advance, the highest quartile (Q4) was associated with a 36.3% increased risk of OA (OR = 1.363; 95% CI = 1.213 to 1.532, p < 0.001). The highest quartile of Pheno-Age advance (Q4) was associated with a 24.3% increased risk of OA compared to Q1 (OR = 1.243; 95% CI = 1.113 to 1.389, p < 0.001). In males and young people, no statistical differences were found in OA risk between the highest and the lowest quartiles of KDM-Age advance (p = 0.151) and Pheno-Age advance (p = 0.057), respectively.

Conclusion

Adults with accelerated biological aging have an increased risk of OA, particularly among females and older adults.
Implementing TeleSleep at Veterans Healthcare Administration: an organizational case study of adaptation and sustainment
Authors: Belkora Jeffrey K. , Reichert Jill , Williams Katherine , Whooley Mary A. , Rezayat Talayeh , Sorensen Stacy , Chilakamarri Priyanka , Sanders Elizabeth , Maas Andrea , Gomez Alexander , Kurien Philip , Ashbrook Liza , Thomas Jacque , Sarmiento Kathleen F.
Published: September 2024

Veteran access to sleep medicine is of paramount importance to the Veterans Health Administration (VA). To increase access, VA has created community referral policies and programs, as well as telehealth programs. In 2017, the Office of Rural Health (ORH) funded a TeleSleep initiative focused on reaching rural Veterans with unmet sleep needs. ORH provided 3–6 years of funding to help 19 hubs support 98 spoke sites serving rural Veterans. As ORH funding concluded, each hub identified its path to sustainment. This case study follows one TeleSleep hub in VA's western geographic region as it transitioned from ORH funding sustainment as a regional Sleep Clinical Resource Hub. This case study describes the real-world process of adaptation in care delivery strategies. One key area of adaptation revolved around whether to deliver care via the patient's home facility or the provider's home facility. In early 2021, the TeleSleep team implemented an innovative provider transfer model, where temporary reinforcements from the TeleSleep hub increased the workforce capacity of spoke sites, similar to the concept of locum tenens. In this provider transfer model, TeleSleep clinicians scheduled, documented, and billed for each encounter at the Veteran's home facility. Positioning TeleSleep clinicians as local providers facilitated communication and referrals and promoted continuity and quality of care for Veterans in their home facility. This provider transfer model reduced the administrative burden of providers and schedulers and supported patient-side-only documentation of care. While this mirrors current locum tenens practice, transferring providers did not fit VA's financial model as implemented by the western region's Sleep Clinical Resource Hub. Therefore, in December 2021, VA aligned TeleSleep with VA's preferred practice of patient rather than provider transfers. In the patient transfer model, providers schedule and document in both the provider and patient electronic health records, and bill in the provider's facility. However, reflecting on this period of innovation, TeleSleep team members concluded that the provider transfer model could improve patient safety and care coordination while reducing the administrative burden of frontline clinicians. Further research and development are needed to align the provider transfer model with VA's financial model.
Esports buffs: the perceived role of fans and fandoms in U.S. collegiate programs
Authors: Cote Amanda C. , Rahman Md Waseq Ur , Foxman Maxwell , Wilson Andrew , Harris Brandon C. , Can Onder , Hansen Jared C.
Published: September 2024

Introduction

Collegiate esports—organized competitive gaming—has expanded rapidly in the United States, drawing in student players, broadcasters, and support staff, as well as university employees. Universities have invested financially in esports, hoping to capitalize on gaming fandom to attract prospective students and enhance campus community integration. Little research, however, addresses collegiate esports fandom in depth.

Methods

Drawing on thirty-one in-depth interviews with collegiate esports players, student workers, program directors, and administrators, this article investigates how collegiate esports participants perceive and discuss their fans.

Results

We identify three central themes related to fans in the dataset: discussions of fans’ role in the collegiate esports environment, comparisons between esports and traditional sports fans, and concerns about the underutilization of fans within collegiate esports spaces. Subsequently, we theorize these themes through existing research on professional esports and traditional collegiate sports fandoms, as well as through the concept of “fan labor,” or how the productive work of fans provides value to the nascent industry.

Discussion

This article thus not only specifically explores how collegiate esports programs are normalizing fan labor as an essential part of their practices, but also questions who benefits from this relationship and how. Investigating collegiate esports fans as an under-researched group additionally provides a new perspective on how fan labor integrates with media industries more broadly.
Pushing forward: exploring the impact of the sitting position on muscle activation patterns and force generation during paralympic sit-cross-country skiing
Authors: Hirsch Leonie , Barioudi Hatim , Wintergerst Dominic , Rombach Ralf , Rapp Walter , Felderhoff Thomas , Mrachacz-Kersting Natalie
Published: September 2024

Paralympic cross-country sit-skiing is a discipline of the Paralympic Winter Games where athletes use a specialized sledge. Athletes are classified into different groups according to their functional abilities. The double poling technique is used to push the sledge forward and generate speed. Different sitting positions in the sledge are used based on the individual impairment. To date there is no data available on the effects of these different positions on muscle activation patterns. The aim of this study was to analyze the muscle activation patterns of the trunk and upper body muscles in relation to the poling force. Nine Able-bodied athletes were tested on a treadmill at submaximal speed in three sitting positions for 4 min in a flat and uphill condition. Sitting positions included a “knee-high” position, a “knee-low” position, and a “neutral” position with the sitting platform parallel to the ground. Unilateral pole forces and surface EMG from three trunk muscles, two upper limb muscles, and one lower limb muscle were recorded simultaneously on the dominate side. Data were segmented into individual cycles and mean values and standard deviations calculated for each subject and condition. Statistical analyses, including a Friedman test and Bonferroni correction, were applied to examine significant differences across different sitting positions. Our findings demonstrate that while certain muscle groups such as the erector spinae and triceps show consistent patterns of activation across different sitting positions, there is considerable variability among individual athletes, suggesting individualized strategies for task execution. Overall, force application was most efficient in the “knee low” position with 691.33 ± 148.83 N and least efficient in the “knee high” position with 582.81 ± 115.11 N. Testing impaired athletes will be the next step in understanding the neurophysiological aspects of the poling movement. This experimental protocol provides a basis for understanding the movement of paralympic cross-country sit-skiing in greater depth.
An investigation into China’s online catering food safety governance efficacy based on the strategies of frequent supervision and strict penalty
Authors: Shen Cong , Wei Mingxia , Li Chaoyang , Hao Xin , Wang Lin
Published: September 2024

Introduction

Enhancing the efficacy of online food safety supervision requires thoughtful selection and efficient application of regulatory measures.

Methods

This study examined the current state of online food safety supervision in the important food producing city in central China of Zhengzhou. The effectiveness of supervision frequency and penalty on food safety governance of online catering was examined through model construction based on the optimal law enforcement theory. The efficacy of monitoring was evaluated using real supervision and punishment data from the online catering sector in a Chinese new first-tier city.

Results and discussion

Results showed that although high-frequency and high-penalty supervision are two common methods of online food safety governance, the deterrent effect of high-frequency supervision on online food businesses is more significant for improving the supervision efficiency of the online catering market. Simultaneously, bolstering the education of caterers and food operators as well as raising their degree of training are also efficient ways to raise the efficacy of government oversight. The application of law enforcement economics is broadened in this study, which also has implication for the advancement of credit rating and classification supervision in the area of food safety for online catering.
Knowledge mapping and bibliometric analysis of medical knee magnetic resonance imaging for knee osteoarthritis (2004–2023)
Authors: Chen Juntao , Xu Hui , Zhou Hang , Wang Zheng , Li Wanyu , Guo Juan , Zhou Yunfeng
Published: September 2024

Objectives

Magnetic resonance imaging (MRI) is increasingly used to detect knee osteoarthritis (KOA). In this study, we aimed to systematically examine the global research status on the application of medical knee MRI in the treatment of KOA, analyze research hotspots, explore future trends, and present results in the form of a knowledge graph.

Methods

The Web of Science core database was searched for studies on medical knee MRI scans in patients with KOA between 2004 and 2023. CiteSpace, SCImago Graphica, and VOSviewer were used for the country, institution, journal, author, reference, and keyword analyses.

Results

A total of 2,904 articles were included. The United States and Europe are leading countries. Boston University is the main institution. Osteoarthritis and cartilage is the main magazine. The most frequently cocited article was “Radiological assessment of osteoarthrosis”. Guermazi A was the author with the highest number of publications and total references. The keywords most closely linked to MRI and KOA were “cartilage”, “pain”, and “injury”.

Conclusions

The application of medical knee MRI in KOA can be divided into the following parts: (1). MRI was used to assess the relationship between the characteristics of local tissue damage and pathological changes and clinical symptoms. (2).The risk factors of KOA were analyzed by MRI to determine the early diagnosis of KOA. (3). MRI was used to evaluate the efficacy of multiple interventions for KOA tissue damage (e.g., cartilage defects, bone marrow edema, bone marrow microfracture, and subchondral bone remodeling). Artificial intelligence, particularly deep learning, has become the focus of research on MRI applications for KOA.
Short-Term Outcomes of Transabdominal Preperitoneal Ventral Hernia Repair With Rectus Aponeuroplasty (TAPPRA) for the Management of Incisional Hernias
Authors: Bosley Maggie E. , Felix Zev , Salgado-Garza Gustavo , Lansing Shan , Nikolian Vahagn C.
Published: September 2024

Introduction

Options for minimally invasive ventral hernia repair continue to evolve as a function of our understanding of the abdominal wall and the development of new techniques. We describe a robotic transabdominal pre-peritoneal repair with concurrent rectus aponeuroplasty (TAPPRA) for incisional and recurrent ventral hernias.

Methods

All patients in this retrospective cohort study underwent TAPPRA repair between October 2023 and March 2024. This study aimed to determine intraoperative feasibility of the technique and to assess immediate postoperative outcomes.

Results

Twelve patients underwent TAPPRA repair for incisional and/or recurrent ventral hernias at an academic hernia center. The median case duration was 135 min with no significant intraoperative complications noted. Average defect size for the hernias measures 6.5 × 8.5 cm. Polypropylene mesh was used to reinforce all defects, with the average dimensions being 19.7 × 21.5 cm. 83% of patients were discharged within 24 h of their procedure. No significant postoperative complications were noted.

Conclusion

We describe the first use of a novel ventral hernia repair technique, TAPPRA, and demonstrate that it is safe, feasible, and associated with appropriate short-term outcomes for repair of moderate sized incisional hernias.
Development and Experimental Study of a Mixed-Mode Vibration Isolator Using Magnetorheological Elastomer
Authors: Liu Qianjie , Guo Zhirong , Liu Wei , Li Gang , Jin Shengzhi , Yu Lei , Hu Guoliang
Published: September 2024

This paper proposes a mixed-mode (combining shear and squeeze working modes) vibration isolator using magnetorheological elastomer (MRE), which enables the isolator to have a larger working area and better isolation performance by combining the working modes of the MRE. Firstly, based on the magnetorheological effect working principle of the MRE, the material selection and dimensional parameters of each component are determined through structural design and magnetic circuit calculation. On this basis, magnetic field simulation is conducted using Maxwell 16.0 software to analyze the distribution of magnetic field lines and magnetic induction in the working area. Simultaneously, equivalent stiffness and equivalent damping models are established to explore the variation of vibration response with external current and excitation frequency conditions. Finally, a vibration isolation experimental platform is built to test the mixed-mode MRE isolator. The experimental results are basically consistent with the simulation modeling results. The experimental results showed that when the external excitation is in the frequency range of 16 Hz, effective semi-active vibration isolation control could be achieved by applying different current inputs. The isolation effect of the system is difficult to effectively control using current input when the external excitation is at high frequency. These results validate the rationality and feasibility of the mixed-mode MRE isolator structure, which provides a good reference for the design of MRE isolators.
A Model of Public Sector E-Services Development Efficiency as a Sustainable Competitive Advantage
Authors: Valackiene Asta , Giedraitiene Jovita
Published: September 2024

This study aims to explore the links between the efficiency of public sector e-services and sustainable competitive advantage. In line with the emerging approach, the instrumental case study design and the mixed research strategy were used as the most appropriate methodology to answer the general research question that was raised for this study. In this context, we present the positive experience that we have discovered via the Lithuanian case study. A unified model of evaluation of the e-services development system in the public sector was developed. The model explains the application of various e-services development systems methodologies and methods in the public sector and underpins the platform for the interaction of efficiency and sustainable competitive advantage processes. The model developed helps to make the assessment of e-services more effective and demonstrates a personalised outcome that can be applied by other public sector organisations. The paper discusses the efficiency trends in the development of e-services in the public sector in order to achieve Sustainable Development Goals, as well as distinguishes and highlights procedural steps that help to improve the development of e-services and sustainable competitive advantage.
Diagnosis of Mechanical Rotor Faults in Drones Using Functional Gaussian Mixture Classifier
Authors: Bartoszewski Bartosz , Jarzyna Kacper , Baranowski Jerzy
Published: September 2024

The article presents the topic of propeller damage detection on unmanned multirotor drones. Propeller damage is dangerous as it can negatively affect the flight of a drone or lead to hazardous situations. The article proposes a non-invasive method for detecting damage within the drone’s hardware, which utilizes existing sensors in the Internal Measuring Unit (IMU) to classify propeller damage. The classification is performed by using the Bayesian Gaussian Mixture Model (BGMM). In the field of drone propeller damage detection, there is a significant issue of data scarcity due to traditional methods often involving invasive and destructive testing, which can lead to the loss of valuable equipment and high costs. Bayesian methods, such as BGMM, are particularly well-suited to address this issue by effectively handling limited data through incorporating prior knowledge and probabilistic reasoning. Moreover, using the IMU for damage detection is highly advantageous as it eliminates the need for additional sensors, reducing overall costs and preventing added weight that could compromise the drone’s performance. IMUs do not require specific environmental conditions to function properly, making them more versatile and practical for real-world applications.
Effect of Multicoaxial Injectors on Nitrogen Film Cooling in a GCH4/GO2 Thrust Chamber for Small-Scale Methane Rocket Engines: A CFD Study
Authors: Radhakrishnan Kanmaniraja , Ha Dong Hwi , Lee Hyoung Jin
Published: September 2024

Improper film cooling design and positioning of an injector in the face plate cause thermal damage to the thrust chamber wall and lead to rocket engine failures. An experimental combustor with five shear coaxial injectors was damaged owing to inadequate film cooling distribution on the thrust chamber wall. The present study aimed to simulate the experimental test case and investigate the causes of the thermal damage. In the simulation, gaseous methane and oxygen were injected at the inner and outer inlets of the shear coaxial injectors and nitrogen, used as the coolant, was injected near the upstream of the chamber wall. The turbulent chemistry interaction was modeled using a reduced DRM-19 mechanism by incorporating the Eddy Dissipation Concept model. Numerical investigations were conducted to examine the cause of thermal damage. The temperature contours of the thrust chamber wall were compared with the experimental image of the damaged wall. Further, simulations of single-row (SR) and multi-row (MR) injector configurations were conducted to assess the effect on film cooling distribution. The adiabatic film cooling effectiveness and specific impulse were determined for all simulated cases. The results showed that MR simulations with narrow injector angles had poor film cooling performance, while wider angles led to lower specific impulse. The face plate with an angle of 15 degrees between the injector positions showed better performance in terms of considering both the film cooling and specific impulse.
A Low Earth Orbit Satellite-Orbit Extrapolation Method Based on Multi-Satellite Ephemeris Coordination and Multi-Stream Fractional Autoregressive Integrated Moving Average
Authors: Lin Wenliang , Yi Jian , Wang Tong , Wang Ke , Huang Zexi , Deng Zhongliang , Liu Yang , Liao Yicheng , Kang Heng , Liu Zeyang , Zhang Junyu
Published: September 2024

The low Earth orbit (LEO) satellite internet network (LEO-SIN) has become a heated issue for the next generation of mobile communications, serving as a crucial means to achieve global wide-area broadband coverage and, especially, mobile phone directly to satellite cell (MPDTSC) communication. The ultra-high-speed movement of LEO satellites relative to the Earth results in serious Doppler effects, leading to signal de-synchronization at the user end (UE), and relative high-speed motion leading to frequent satellite handovers. Satellite ephemeris, which indicates the satellite’s position, has the potential to determine the position of the transmit (Tx) within the LEO-SIN, thereby enhancing the reliability and efficiency of satellite communication. The adoption of ephemeris in the LEO-SIN has met some new challenges: (1) how UEs can acquire ephemerides before signal synchronization is complete, (2) how to minimize the frequency of ephemeris broadcasting, and (3) how to decrease the overhead of ephemeris broadcasting. To address the above challenges, this paper proposes a method for extrapolating the LEO-SIN orbit based on multi-satellite ephemeris coordination (MSEC) and the multi-stream fractional autoregressive integrated moving average (MS-FARIMA). First, a multi-factor global error analysis model for ephemeris-extrapolation error is established, which decomposes it into three types; namely, random error (RE), trending error (TE), and periodic error (PE), with a focus on increasing the extrapolation accuracy by improving RE and TE. Second, RE is eliminated by utilizing the ephemerides from multiple satellites received at the same UE at the same time, as well as multiple ephemerides from the same satellite at different times. Subsequently, we propose a new FARIMA algorithm with the innovation of a multi-stream data time-series forecast (TSF), which effectively improves ephemeris extrapolation errors. Finally, the simulation results show that the proposed method reduces ephemeris extrapolation errors by 33.5% compared to existing methods, which also contributes to a performance enhancement in the Doppler frequency offset (DFO) estimation of MPDTSC.
Interpretable Digital Soil Organic Matter Mapping Based on Geographical Gaussian Process-Generalized Additive Model (GGP-GAM)
Authors: Cheng Liangwei , Yan Mingzhi , Zhang Wenhui , Guan Weiyan , Zhong Lang , Xu Jianbo
Published: September 2024

Soil organic matter (SOM) is a key soil component. Determining its spatial distribution is necessary for precision agriculture and to understand the ecosystem services that soil provides. However, field SOM studies are severely limited by time and costs. To obtain a spatially continuous distribution map of SOM content, it is necessary to conduct digital soil mapping (DSM). In addition, there is a vital need for both accuracy and interpretability in SOM mapping, which is difficult to achieve with conventional DSM models. To address the above issues, particularly mapping SOM content, a spatial coefficient of variation (SVC) regression model, the Geographic Gaussian Process Generalized Additive Model (GGP-GAM), was used. The root mean squared error (RMSE), mean average error (MAE), and adjusted coefficient of determination (adjusted R2) of this model for SOM mapping in Leizhou area are 7.79, 6.01, and 0.33 g kg−1, respectively. GGP-GAM is more accurate compared to the other three models (i.e., Geographical Random Forest, Geographically Weighted Regression, and Regression Kriging). Moreover, the patterns of covariates affecting SOM are interpreted by mapping coefficients of each predictor individually. The results show that GGP-GAM can be used for the high-precision mapping of SOM content with good interpretability. This DSM technique will in turn contribute to agricultural sustainability and decision making.
Simulation and Testing of Grapevine Branch Crushing and Collection Components
Authors: He Lei , Wang Zhimin , Song Long , Bao Pengyu , Cao Silin
Published: September 2024

Aiming at the problem of the low rate of resource utilization of large amounts of grape branch pruning and the high cost of leaving the garden, we design a kind of grape branch picking and crushing collection machine that integrates the collection of strips, the picking up, crushing, and collecting operations. The crushing and collecting parts of the machine are simulated, analyzed, and tested. Using the method of numerical simulation, combined with the results of the pre-branch material properties measurement, the branch crushing process is simulated based on LS-DYNA software. Our analysis found that in the branch destruction process, not only does knife cutting exist, but the bending fracture of the opposite side of the cutting place also exists. With the increase in the knife roller speed, the cutting resistance of the tool increases, reaching 2690 N at 2500 r/min. In the cutting simulation under different tool edge angles, the cutting resistance of the tool is the smallest when the edge angle is 55°, which is 1860 N, and this edge angle is more suitable for branch crushing and cutting. In the cutting simulation under different cutting edge angles, the cutting resistance of the tool is the smallest when the edge angle is 55°, which is 1860 N, and this edge angle is more suitable for branch crushing and cutting. Using Fluent software to analyze the characteristics of the airflow field of the pulverizing device, it was found that with the increase in the knife roller speed, the inlet flow and negative pressure of the pulverizing chamber increase. When the knife roller speed is 2500 r/min, the inlet flow rate and negative pressure are 1.92 kg/s and 37.16 Pa, respectively, which will be favorable to the feeding of the branches, but the speed is too high and will also lead to the enhancement of the vortex in some areas within the pulverizing device, which will in turn affect the feeding of the branches as well as the throwing out of pulverized materials. Therefore, the speed range of the pulverizing knife roller was finally determined to be 1800~2220 r/min. Based on the ANSYS/Model module modal analysis of the crushing knife roller, the knife roller of the first six orders of the intrinsic frequency and vibration pattern, the crushing knife roller of the lowest order had a modal intrinsic frequency of 137.42 Hz, much larger than the crushing knife roller operating frequency of 37 Hz, above which the machine will not resonate during operation. The research results can provide a theoretical basis and technical support for other similar crops to be crushed and collected.
Recent Advances in Agricultural Robots for Automated Weeding
Authors: Lytridis Chris , Pachidis Theodore
Published: September 2024

Weeds are one of the primary concerns in agriculture since they compete with crops for nutrients and water, and they also attract insects and pests and are, therefore, hindering crop yield. Moreover, seasonal labour shortages necessitate the automation of such agricultural tasks using machines. For this reason, advances in agricultural robotics have led to many attempts to produce autonomous machines that aim to address the task of weeding both effectively and efficiently. Some of these machines are implementing chemical-based weeding methods using herbicides. The challenge for these machines is the targeted delivery of the herbicide so that the environmental impact of the chemical is minimised. However, environmental concerns drive weeding robots away from herbicide use and increasingly utilise mechanical weeding tools or even laser-based devices. In this case, the challenge is the development and application of effective tools. This paper reviews the progress made in the field of weeding robots during the last decade. Trends during this period are identified, and the current state-of-the-art works are highlighted. Finally, the paper examines the areas where the current technological solutions are still lacking, and recommendations on future directions are made.
Toward Flexible Soil Texture Detection by Exploiting Deep Spectrum and Texture Coding
Authors: Ma Ruijun , Jiang Jun , Ouyang Lin , Yang Qingying , Du Jiongxuan , Wu Shuanglong , Qi Long , Hou Junwei , Xing Hang
Published: September 2024

Soil texture is a significant attribute of soil properties. Obtaining insight into the soil texture is beneficial when making agricultural decisions during production. Nevertheless, assessing the soil texture in specific laboratory conditions entails substantial dedication, which is time-consuming and includes a high cost. In this paper, we propose a soil texture detection network by embedding the frequency channel attention network and a texture encoding network into the representation learning paradigm of the ResNet framework. Concretely, the former is reliable in exploiting the feature correlations among multi-frequency, while the latter focuses on encoding feature variables, jointly enhancing the ability of feature expression. Meanwhile, the clay, silt, and sand particles present in the soil are exported through a ResNet18 fully linked layer. Experimental results show that the correlation coefficient for predicting clay, silt, and sand content are 0.931, 0.936, and 0.957, respectively. For the root mean square error, the quantitative scores are 2.106%, 3.390%, and 3.602%, respectively. The proposed network also exhibits proposing generalization capability, yielding quite considerable results on different soil samples. Notably, the detection results are almost in agreement with the conventional laboratory measurements, and, at the same time, outperform other competitors, making it highly attractive for practical applications.
Key Factors Controlling Cadmium and Lead Contents in Rice Grains of Plants Grown in Soil with Different Cadmium Levels from an Area with Typical Karst Geology
Authors: Li Long , Ma Lijun , Tang Lebin , Huang Fengyan , Xiao Naichuan , Zhang Long , Song Bo
Published: September 2024

Cadmium (Cd) is a naturally occurring element often associated with lead (Pb) in the Earth’s crust, particularly in karst regions, posing significant safety hazards for locally grown rice. Identifying the key factors controlling Cd and Pb content in local rice is essential under the natural soil condition, as this will provide a crucial theoretical foundation for implementing security intervention measures within the local rice-growing industry. This study collected three types of paddy field soils with varying Cd concentrations from karst areas for pot experiments. The rice varieties tested included a low-Cd-accumulating variety, a high-Cd-accumulating variety, and a locally cultivated variety. Soil physicochemical properties and plant physiological indices were monitored throughout the rice growth stages. These data were used to construct a segmented regression model of Cd and Pb levels in rice grains based on the plant’s metabolic pathways and the structure of polynomial regression equations. Stepwise regression identified the key factors controlling Cd and Pb accumulation in rice grains. In conclusion, the key factors controlling Cd and Pb levels in rice grains should be classified into two categories: (i) factors influencing accumulation in roots and (ii) factors regulating transport from roots to grains. The aboveground translocation abilities for Cd, Pb, zinc (Zn), iron (Fe), manganese (Mn), calcium (Ca), and magnesium (Mg) in soil among the three rice varieties showed no significant interspecific differences under identical soil conditions. Soil Mg uptake by rice roots may represent a key mechanism for inhibiting soil Cd uptake by rice roots. In karst areas with high background soil Cd, increased soil organic matter (SOM) levels enhance Pb bioavailability. Additionally, the rice YXY may possess a potential for low Cd accumulation.