bluuebunny/crossref_metadata_2025 huggingface dataset:
Prevalence of Cobalt in the Environment and Its Role in Biological Processes
Authors: Genchi Giuseppe , Lauria Graziantonio , Catalano Alessia , Carocci Alessia , Sinicropi Maria Stefania
Published: October 2023

Cobalt (Co) is an essential trace element for humans and other animals, but high doses can be harmful to human health. It is present in some foods such as green vegetables, various spices, meat, milk products, seafood, and eggs, and in drinking water. Co is necessary for the metabolism of human beings and animals due to its key role in the formation of vitamin B12, also known as cobalamin, the biological reservoir of Co. In high concentrations, Co may cause some health issues such as vomiting, nausea, diarrhea, bleeding, low blood pressure, heart diseases, thyroid damage, hair loss, bone defects, and the inhibition of some enzyme activities. Conversely, Co deficiency can lead to anorexia, chronic swelling, and detrimental anemia. Co nanoparticles have different and various biomedical applications thanks to their antioxidant, antimicrobial, anticancer, and antidiabetic properties. In addition, Co and cobalt oxide nanoparticles can be used in lithium-ion batteries, as a catalyst, a carrier for targeted drug delivery, a gas sensor, an electronic thin film, and in energy storage. Accumulation of Co in agriculture and humans, due to natural and anthropogenic factors, represents a global problem affecting water quality and human and animal health. Besides the common chelating agents used for Co intoxication, phytoremediation is an interesting environmental technology for cleaning up soil contaminated with Co. The occurrence of Co in the environment is discussed and its involvement in biological processes is underlined. Toxicological aspects related to Co are also examined in this review.
Red Blood Cell-Derived Extracellular Vesicles: An Overview of Current Research Progress, Challenges, and Opportunities
Authors: Ma Si-Rui , Xia Hou-Fu , Gong Ping , Yu Zi-Li
Published: October 2023

Red blood cell-derived extracellular vesicles (RBC EVs) are small, spherical fragments released from red blood cells. These vesicles, similar to EVs derived from other cell types, are crucial for intercellular communication processes and have been implicated in various physiological and pathological processes. The diagnostic and therapeutic potential of RBC EVs has garnered increasing attention in recent years, revealing their valuable role in the field of medicine. In this review, we aim to provide a comprehensive analysis of the current research status of RBC EVs. We summarize existing studies and highlight the progress made in understanding the characteristics and functions of RBC EVs, with a particular focus on their biological roles in different diseases. We also discuss their potential utility as diagnostic and prognostic biomarkers in diseases and as vectors for drug delivery. Furthermore, we emphasize the need for further research to achieve selective purification of RBC EVs and unravel their heterogeneity, which will allow for a deeper understanding of their diverse functions and exploration of their potential applications in diagnostics and therapeutics.
Non-Pharmacological Pain Treatment of Patients with Myofascial Pain Syndrome of the Masticatory Muscles—Case Series
Authors: Macrì Monica , Rotelli Chiara , Pegreffi Francesco , Festa Felice
Published: October 2023

Myofascial pain is the most common cause of chronic pain in the masticatory region and can be assessed through clinical analysis and muscle palpation. Generally, it appears with headache and orofacial pain associated with sensitive points (trigger points) due to the excessive contraction of the masticatory muscle fibers. The study aims to evaluate how a correct treatment of myofascial pain can improve the life quality of affected patients. In this case series, 300 patients with myofascial pain were divided into two groups: 150 with intra- and extra-articular disorders and 150 with only extra-articular disorder. Each group included 75 males and 75 females. All the patients were treated with gnathological therapy through passive aligners and biofeedback exercises for four months. They underwent pain assessment (through a visual analogue scale and muscular palpation test) before, during, and after the treatment, as well as nuclear magnetic resonance of the temporomandibular joint before and after the gnathological treatment. The treatment considerably reduced the pain in all patients, without drugs, in four months according to the visual analogue scales and the palpation test. The temporomandibular magnetic resonance in each patient was similar before and after the gnathological treatment. The improvement in pain did not depend on a change in the relationship between the articular condyle and the disc.
Analyzing Facial Asymmetry in Alzheimer’s Dementia Using Image-Based Technology
Authors: Chien Ching-Fang , Sung Jia-Li , Wang Chung-Pang , Yen Chen-Wen , Yang Yuan-Han
Published: October 2023

Several studies have demonstrated accelerated brain aging in Alzheimer’s dementia (AD). Previous studies have also reported that facial asymmetry increases with age. Because obtaining facial images is much easier than obtaining brain images, the aim of this work was to investigate whether AD exhibits accelerated aging patterns in facial asymmetry. We developed new facial asymmetry measures to compare Alzheimer’s patients with healthy controls. A three-dimensional camera was used to capture facial images, and 68 facial landmarks were identified using an open-source machine-learning algorithm called OpenFace. A standard image registration method was used to align the three-dimensional original and mirrored facial images. This study used the registration error, representing landmark superimposition asymmetry distances, to examine 29 pairs of landmarks to characterize facial asymmetry. After comparing the facial images of 150 patients with AD with those of 150 age- and sex-matched non-demented controls, we found that the asymmetry of 20 landmarks was significantly different in AD than in the controls (p < 0.05). The AD-linked asymmetry was concentrated in the face edge, eyebrows, eyes, nostrils, and mouth. Facial asymmetry evaluation may thus serve as a tool for the detection of AD.
Sensorimotor Uncertainty of Immersive Virtual Reality Environments for People in Pain: Scoping Review
Authors: Flores-Cortes Mar , Guerra-Armas Javier , Pineda-Galan Consolacion , La Touche Roy , Luque-Suarez Alejandro
Published: October 2023

Introduction: Decision making and action execution both rely on sensory information, and their primary objective is to minimise uncertainty. Virtual reality (VR) introduces uncertainty due to the imprecision of perceptual information. The concept of “sensorimotor uncertainty” is a pivotal element in the interplay between perception and action within the VR environment. The role of immersive VR in the four stages of motor behaviour decision making in people with pain has been previously discussed. These four processing levels are the basis to understand the uncertainty that a patient experiences when using VR: sensory information, current state, transition rules, and the outcome obtained. Methods: This review examines the different types of uncertainty that a patient may experience when they are immersed in a virtual reality environment in a context of pain. Randomised clinical trials, a secondary analysis of randomised clinical trials, and pilot randomised clinical trials related to the scope of Sensorimotor Uncertainty in Immersive Virtual Reality were included after searching. Results: Fifty studies were included in this review. They were divided into four categories regarding the type of uncertainty the intervention created and the stage of the decision-making model. Conclusions: Immersive virtual reality makes it possible to alter sensorimotor uncertainty, but studies of higher methodological quality are needed on this topic, as well as an exploration into the patient profile for pain management using immersive VR.
Sleep and Well-Being during the COVID-19 Remote and In-Person Periods: Experiences of College Faculty and Staff with and without Disabilities
Authors: Fichten Catherine S. , Wing Samantha , Costin Georgiana , Jorgensen Mary , Havel Alice , Wileman Susie , Bailes Sally , Creti Laura , Libman Eva
Published: October 2023

We explored the impacts of the remote and return-to-in-person work periods on sleep and well-being as reported by faculty (n = 22) and non-teaching staff (n = 21) with and without disabilities. Participants were recruited through college platforms and personal contacts. Our results show that contrary to expectations, the COVID-19 remote teaching/working period resulted in better sleep, as well as greater well-being, than the return-to-in-person work period. With respect to sleep, faculty members had slightly more negative outcomes than staff, most evident in heightened anxiety and work aspects. Faculty with disabilities had somewhat worse sleep and well-being during the remote period than faculty without disabilities. During the return to in-person work, both faculty and non-teaching staff reported more negative than positive sleep and well-being outcomes. In particular, during the in-person period, faculty members experienced slightly more negative sleep outcomes related to anxiety and work, while staff members experienced slightly more negative sleep outcomes related to the need to commute and lifestyle. Our findings show that there were benefits and disadvantages to both remote and in-person work periods, suggesting a hybrid work schedule should be considered in more detail, particularly as an optional reasonable accommodation for faculty and staff with disabilities. Our study highlights that training to keep faculty abreast of the latest technological innovations, ways to promote work–life balance, and steps to remedy classroom size and building ventilation to prevent the spread of disease all need urgent attention.
Cross-Level Influence of Group-Focused Transformational Leadership on Organizational Citizenship Behavior among Chinese Secondary School Teachers
Authors: Fang Zhuotao , Yu Shun-Chi
Published: October 2023

The organizational citizenship behavior of teachers holds paramount significance in elevating school organizational effectiveness and sustaining competitive advantage. To address this, this study examines the cross-level influence of group-focused transformational leadership on organizational citizenship behavior among secondary school teachers. This exploration includes investigating the mediating role of individual-level psychological contract fulfillment and the moderating impact of group-level collectivism. An empirical investigation involving 1162 secondary school teachers in China was designed for this purpose. The results demonstrate that group-focused transformational leadership significantly positively impacts teachers’ organizational citizenship behavior. Moreover, this relationship is positively moderated by collectivism at the group level, suggesting a stronger effect of transformational leadership on organizational citizenship behavior in more collective-oriented groups. Additionally, the findings reveal that psychological contract fulfillment at the individual level mediates this cross-level relationship, providing evidence for its role in translating leadership’s influence to organizational citizenship behavior. The findings underscore the significance of concentrating on group-focused transformational leadership, cultivating a collectivist atmosphere, and guaranteeing the fulfillment of psychological contracts as pivotal strategies for bolstering organizational citizenship behavior among teachers.
Niosomal Delivery of Celecoxib and Metformin for Targeted Breast Cancer Treatment
Authors: Basheer Haneen A. , Alhusban Maram A. , Zaid Alkilani Ahlam , Alshishani Anas , Elsalem Lina , Afarinkia Kamyar
Published: October 2023

Breast cancer continues to be a prominent worldwide health concern and requires continued investigation into innovative therapeutic approaches. Here, we report the first investigation into the therapeutic efficacy of combining Metformin (MET) and Celecoxib (CXB), both in free and niosomal form, for the treatment of breast cancer. Our investigation encompassed the characterization of these niosomal drug carriers, their stability assessment, and their effect on breast cancer cell models. The thin-film hydration technique was employed to prepare niosomes with spherical, uniform-size distributions and high encapsulation efficiencies. The niosomes were characterized by TEM, particle size analyzer, and ATR-FTIR. The niosomes with an average size of 110.6 ± 0.6 and 96.7 ± 0.7, respectively, for MET and CXB were stable when stored at 4 °C for three months with minimal drug leakage, minor changes in encapsulation efficiency and size, and unchanged physicochemical parameters. Evaluation in two-dimensional (2D) and three-dimensional (3D) viability assays demonstrated an increased cytotoxicity of encapsulated drugs when compared to their free-drug counterparts. Additionally, the combination of Metformin Niosomal Particles (MET NPs) and Celecoxib Niosomal Particles (CXB NPs) led to decreased cell viability in both 2D and 3D models compared to each drug administered individually. When comparing the effect of the niosomal versus the free combination of the drugs on cell migration, we found that both interventions effectively prevented cell migration. However, the efficacy of the niosomes’ combination was not superior to that of the free drug combination (p < 0.05). In conclusion, the results of this study provide valuable insights into the potential application of combining MET and CXB nanoparticle delivery systems to breast cancer treatment. Exploring the in vivo application of this drug delivery system could open new avenues for more effective and targeted therapeutic approaches for breast cancer patients.
Proteomic Profiling of Small-Cell Lung Cancer: A Systematic Review
Authors: Elshoeibi Amgad Mohamed , Elsayed Basel , Kaleem Muhammad Zain , Elhadary Mohamed Ragab , Abu-Haweeleh Mohannad Natheef , Haithm Yunes , Krzyslak Hubert , Vranic Semir , Pedersen Shona
Published: October 2023

The accurate diagnosis of small-cell lung cancer (SCLC) is crucial, as treatment strategies differ from those of other lung cancers. This systematic review aims to identify proteins differentially expressed in SCLC compared to normal lung tissue, evaluating their potential utility in diagnosing and prognosing the disease. Additionally, the study identifies proteins differentially expressed between SCLC and large cell neuroendocrine carcinoma (LCNEC), aiming to discover biomarkers distinguishing between these two subtypes of neuroendocrine lung cancers. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, a comprehensive search was conducted across PubMed/MEDLINE, Scopus, Embase, and Web of Science databases. Studies reporting proteomics information and confirming SCLC and/or LCNEC through histopathological and/or cytopathological examination were included, while review articles, non-original articles, and studies based on animal samples or cell lines were excluded. The initial search yielded 1705 articles, and after deduplication and screening, 16 articles were deemed eligible. These studies revealed 117 unique proteins significantly differentially expressed in SCLC compared to normal lung tissue, along with 37 unique proteins differentially expressed between SCLC and LCNEC. In conclusion, this review highlights the potential of proteomics technology in identifying novel biomarkers for diagnosing SCLC, predicting its prognosis, and distinguishing it from LCNEC.
KEAP1/NRF2 Mutations in Stem Cells Define an Aggressive Subset of Head and Neck Cancer Patients Who Have a Poor Prognosis, Lung Metastasis, and Therapeutic Failure
Authors: Islam Syed S. , Karakas Bedri , Aboussekhra Abdelilah , Noman Abu Shadat M.
Published: October 2023

Mutations in Keap1/Nrf2 in head and neck cancer result in abnormal cell growth. Progenitor cells, bulk tumor cells, and head and neck cancer stem cells (HN-CSCs) may all harbor these mutations. Nevertheless, whether Keap1/Nrf2 mutations in HN-CSCs have an impact on clinical outcomes is unknown. Cancerous HN-CSCs and benign stem cells were obtained from freshly resected head and neck cancer patients (n = 50) via flow cytometry cell sorting and tested for Keap1/Nrf2 mutations. The existence of Keap1/Nrf2 mutations in HN-CSCs, as well as their correlations with tumor mutations, pathologic tumor stage, tumor histologic grades, lung metastasis, treatment outcomes, and the patient’s age and conditions, are assessed at the last follow-up visit. Thirteen tumors were found to have Keap1/Nrf2 mutations in their HN-CSCs. More than half of the lung metastases and disease progression occurred in HN-CSCs with mutations. Patients whose tumors carried Keap1/Nrf2 mutations in their HN-CSCs had significantly shorter progression-free survival, overall survival, and time of treatment failure than their non-HN-CSC counterparts. These associations were partly driven by HN-CSCs, in which Keap1/Nrf2 mutations were overrepresented in fast progressors and associated with an increased risk of disease progression. Our findings suggest that molecular genotyping of HN-CSCs may facilitate personalized treatment strategies and assist in identifying patients who are likely to benefit from chemotherapy.
The Evolving Role of Stereotactic Body Radiation Therapy for Head and Neck Cancer: Where Do We Stand?
Authors: Mohamad Issa , Karam Irene , El-Sehemy Ahmed , Abu-Gheida Ibrahim , Al-Ibraheem Akram , AL-Assaf Hossam , Aldehaim Mohammed , Alghamdi Majed , Alotain Ibrahim , Ashour May , Bushehri Ahmad , ElHaddad Mostafa , Hosni Ali
Published: October 2023

Stereotactic body radiation therapy (SBRT) is a precise and conformal radiation therapy (RT) that aims to deliver a high dose of radiation to the tumor whilst sparing surrounding normal tissue, making it an attractive option for head and neck cancer (HNC) patients who are not suitable for the traditional long course of RT with comprehensive RT target volume. Definitive SBRT for HNC has been investigated in different settings, including early stage glottis cancer, and as an alternative to brachytherapy boost after external beam RT. It is also used as a primary treatment option for elderly or medically unfit patients. More recently, an SBRT combination with immunotherapy in the neoadjuvant setting for HNC showed promising results. Salvage or adjuvant SBRT for HNC can be used in appropriately selected cases. Future studies are warranted to determine the optimum dose and fractionation schedules in any of these indications.
Aminocyclopropenium as a New Class of Hydrogen Bonding Catalyst in Friedel–Crafts Alkylation
Authors: Ma Xuesuo , Xu Jiaxi , Liu Jingjing , He Jun , Chang Tong , Yang Qingbiao , Li Ning , Qian Dong , Li Zhenjiang
Published: October 2023

H-bonding has achieved massive advancements by utilizing an H-bond donor (HBD) to interact with the electron-rich site of the substrate, and an H-bond acceptor (HBA) to coordinate with the electron-deficient site. Rapid transformation is often correlated with the acidity of HBD, namely the degree of charge deficiency of the hydrogen proton. In addition, the positive cations were employed to enhance the HBD; the electron-withdrawing groups were also a dissimilar approach for increasing the capability of the H-bond donor. We first introduced the H-bonding organic ion pair tris(phenylamino)cyclopropenium (TPAC·Cl) into the Friedel–Crafts alkylation of indoles with nitroalkenes, which was implemented via vicinal positive charges on the cyclopropenium core. The counter ion chloride anion became a potential HBA to activate the electron-deficient part of the substrate. X-ray analyses of a single crystal of TPAC·Cl described the 3D architecture and the delocalized cationic charge in the solid state. The aromatic cyclopropenium endowed the N–H moieties with the ability of the H-bond donor to activate the nitroalkene; meanwhile, the chloride anion acted as the H-bond acceptor to activate the indole. The amino-cyclopropenium-offered HBD and HBA displayed cooperative organocatalysis in the Friedel–Crafts alkylation of indole with nitroalkene. A new class of hydrogen bonding catalysis and a working mechanism were proposed.
Body Image and Psychological Impact of Dental Appearance in Adolescents with Malocclusion: A Preliminary Exploratory Study
Authors: Sicari Federica , Merlo Emanuele Maria , Gentile Giulia , Nucera Riccardo , Portelli Marco , Settineri Salvatore , Myles Liam Alexander MacKenzie , Militi Angela
Published: October 2023

Background: Body image and psychosocial functioning represent central challenges during adolescence and early adulthood. Malocclusion, defined as an irregularity in the alignment of the teeth, is known to negatively influence psychological outcomes. The current study aimed to elucidate the role of malocclusion, together with age, gender, and dental class, in body image and psychological functioning. Methods: A total of 126 participants aged from 12 to 19 years old (mean: 15.87, SD: 2.35, female participants: 52.4%, male participants: 47.6%) were recruited. Participants were visited at the University Hospital of Messina, Italy, and completed a sociodemographic questionnaire, the Body Image Concern Inventory (I-BICI), and the Psychosocial Impact of Dental Aesthetics Questionnaire (PIDAQ). Results: Significant correlations were found between age, dental class, the BICI, and the PIDAQ. In particular, age showed a positive and significant correlation with PIDAQ—total score. The correlations between occlusal status and the BICI variables were all significant and positive. All correlations between occlusal status and the PIDAQ variables were all significant and positive, except for dental self-confidence. The correlations between the variables of the PIDAQ and BICI instruments were all significant and positive, except for dental self-confidence, where the directions were significant and negative. Moreover, age, gender, and occlusal status predicted BICI and PIDAQ scores. Age was a positive predictor for PIDAQ self-confidence, gender for BICI and PIDAQ total scores, along with dysmorphic symptoms, social impact, psychological impact, and aesthetic concerns. Several significant gender differences were highlighted by the analyses, with higher scores in the female group on all the BICI variables, except symptom interference, and all the PIDAQ variables, except dental self-confidence. Conclusions: Malocclusion appeared to play a central role in the psychological, representational, and psychosocial life of the participants. This research suggests that malocclusion and dental issues influence the psychological, representational, and psychosocial life of adolescents. Further research is required to examine the psychological impact of dental problems.
A Process Evaluation of Intervention Delivery for a Cancer Survivorship Rehabilitation Clinical Trial Conducted during the COVID-19 Pandemic
Authors: Stevens Courtney J. , Wechsler Stephen , Ejem Deborah B. , Khalidi Sarah , Coffee-Dunning Jazmine , Morency Jamme L. , Thorp Karen E. , Codini Megan E. , Newman Robin M. , Echols Jennifer , Cloyd Danielle Z. , dos Anjos Sarah , Muse Colleen , Gallups Sarah , Goedeken Susan C. , Flannery Kaitlin , Bakitas Marie A. , Hegel Mark T. , Lyons Kathleen Doyle
Published: October 2023

The purpose of the present study was to conduct a process evaluation of intervention delivery for a randomized controlled trial (RCT) conducted during the COVID-19 pandemic (NCT 03915548). The RCT tested the effects of a telephone-delivered behavioral intervention on changes in breast cancer survivors’ satisfaction with social roles and activities, as compared to an attention control condition. This process evaluation examined (a) fidelity monitoring scores; (b) participants’ perceived benefit ratings for gaining confidence, reducing distress, adjusting habits and routines, setting goals, and increasing exercise; and (c) field notes, email communications, and transcripts of coach supervision and debriefing sessions. The behavioral and attention control conditions were delivered with a high degree of fidelity (global quality rating score for the BA/PS condition was M = 4.6 (SD = 0.6) and M = 4.9 (SD = 0.3) for the attention control condition, where “5” is the highest rating). The behavioral intervention participants perceived greater benefits than the control participants pertaining to goal setting, t(248) = 5.73, p = <0.0001, adjusting habits and routines, t(248) = 2.94, p = 0.0036, and increasing exercise, t(248) = 4.66, p = <0.0001. Moreover, coaches’ perceptions regarding the behavioral intervention’s therapeutic aspects aligned with the study’s a priori conceptual model including the use of a structured process to set small, observable goals and facilitate the independent use of problem-solving skills. However, coaches also noted that aspects of the attention control condition, including the perceived relevance of the educational content and opportunities for social support, may have made it more therapeutically potent than intended. The pandemic may have affected the activity goals behavioral intervention participants could set as well as augmented the relevancy of social support provided in both conditions.
Derivation of a HEAR Pathway for Emergency Department Chest Pain Patients to Safely Avoid a Second Troponin Test
Authors: Chen Chen , Yu Yao , Chen Dongxu , Cai Canguang , Zhou Yannan , Liao Fengqing , Humarbek Alima , Li Xuan , Song Zhenju , Sun Zhan , Tong Chaoyang , Yao Chenling , Gu Guorong
Published: October 2023

The study aims to develop a decision pathway based on HEAR score and 0 h high-sensitivity cardiac troponin T (hs-cTnT) to safely avoid a second troponin test for suspected non-ST elevation myocardial infarction (NSTEMI) in emergency departments. A HEAR score consists of history, electrocardiogram, age, and risk factors. A HEAR pathway is established using a Bayesian approach based on a predefined safety threshold of NSTEMI prevalence in the rule-out group. In total, 7131 patients were retrospectively enrolled, 582 (8.2%) with index visit NSTEMI and 940 (13.2%) with 180-day major adverse cardiovascular events (MACE). For patients with a low-risk HEAR score (0 to 2) and low 0 h hs-cTnT (<14 ng/L), the HEAR pathway recommends early discharge without further testing. After the HEAR pathway had been applied to rule out NSTEMI, the negative predictive value of index visit NSTEMI was 100.0% (95% CI, 99.8% to 100.0%) and false-negative rate of 180-day MACE was 0.40% (95% CI, 0.18% to 0.87%). Compared with the 0 h hs-cTnT < limit of detection (LoD) strategy (<5 ng/L), the HEAR pathway could correctly reclassify 1298 patients without MACE as low risk and lead to a 18.2% decrease (95% CI, 17.4–19.1%) in the need for a second troponin test. The HEAR pathway may lead to a substantial and safe reduction in repeated troponin test for emergency department patients with suspected NSTEMI.
Weil’s Disease in an HIV-Infected Patient: A Case Report and Literature Review
Authors: Zheng Xinchun , He Pengyuan , Zhong Ruihua , Chen Gongqi , Xia Jinyu , Li Chunna
Published: October 2023

Weil’s disease, an icterohemorrhagic infection, is the most severe and fatal form of leptospirosis and is characterized by jaundice, renal dysfunction, and hemorrhagic predisposition. Weil’s disease with HIV infection has rarely been reported. A 68-year-old male with HIV infection presented to our hospital with fever and dyspnea that progressed to severe hemoptysis and systemic multiple organ failure, necessitating a tracheal intubation ventilator. A diagnosis of Weil’s disease was made after Leptospira interrogans was identified via metagenomic next-generation sequencing (mNGS) in bronchoalveolar lavage fluid (BALF). After immediately receiving supportive therapy and targeted antimicrobial agents, the patient achieved complete recovery upon discharge. The co-infection of HIV infection and leptospirosis resulting in systemic multi-organ failure is rare, but awareness should be raised of the differential diagnosis. mNGS can help identify pathogens and facilitate the use of targeted and efficacious antimicrobial therapy in unusual clinical environments.
Bubble Plume Tracking Using a Backseat Driver on an Autonomous Underwater Vehicle
Authors: Hwang Jimin , Bose Neil , Millar Gina , Bulger Craig , Nazareth Ginelle
Published: October 2023

Autonomous underwater vehicles (AUVs) have been applied in various scientific missions including oceanographic research, bathymetry studies, sea mine detection, and marine pollution tracking. We have designed and field-tested in the ocean a backseat driver autonomous system for a 5.5 m survey-class Explorer AUV to detect and track a mixed-phase oil plume. While the first driver is responsible for controlling and safely operating the vehicle; the second driver processes real-time data surrounding the vehicle based on in situ sensor measurements and adaptively modifies the mission details. This adaptive sensing and tracking method uses the Gaussian blur and occupancy grid method. Using a large bubble plume as a proxy, our approach enables real-time adaptive modifications to the AUV’s mission details, and field tests show successful plume detection and tracking. Our results provide for remote detection of underwater oil plumes and enhanced autonomy with these large AUVs.
Automatic P-Phase-Onset-Time-Picking Method of Microseismic Monitoring Signal of Underground Mine Based on Noise Reduction and Multiple Detection Indexes
Authors: Dai Rui , Wang Yibo , Zhang Da , Ji Hu
Published: October 2023

The underground pressure disaster caused by the exploitation of deep mineral resources has become a major hidden danger restricting the safe production of mines. Microseismic monitoring technology is a universally recognized means of underground pressure monitoring and early warning. In this paper, the wavelet coefficient threshold denoising method in the time–frequency domain, STA/LTA method, AIC method, and skew and kurtosis method are studied, and the automatic P-phase-onset-time-picking model based on noise reduction and multiple detection indexes is established. Through the effect analysis of microseismic signals collected by microseismic monitoring system of coral Tungsten Mine in Guangxi, automatic P-phase onset time picking is realized, the reliability of the P-phase-onset-time-picking method proposed in this paper based on noise reduction and multiple detection indexes is verified. The picking accuracy can still be guaranteed under the severe signal interference of background noise, power frequency interference and manual activity in the underground mine, which is of great significance to the data processing and analysis of microseismic monitoring.
From Protected Habitat to Agricultural Land: Dogs and Small Mammals Link Habitats in Northern Thailand
Authors: Thinphovong Chuanphot , Kritiyakan Anamika , Chakngean Ronnakrit , Paladsing Yossapong , Makaew Phurin , Labadie Morgane , Mahuzier Christophe , Phimpraphai Waraphon , Morand Serge , Chaisiri Kittipong
Published: October 2023

Wildlife communities are positively affected by ecological restoration and reforestation. Understanding the dynamics of mammal communities along a gradient of a human-dominated habitat to a protected habitats, right up to a reforestation habitat, is crucial for assessing the effects of reforestation on conservation biology and disease ecology. We used data obtained from a set of camera traps and live traps implemented in the “Spillover Interface” project. A network analysis showed that the reforested area was central in the sharing of mammal species between human-dominated habitats, such as plantations, and the protected area. A network analysis also confirmed the centrality of the domestic dog and the rodent Rattus tanezumi (R. tanezumi) in shared habitats and the co-occurrence with other mammal species. This rodent species was previously mentioned as a bridge species between habitats favouring disease transmission. This study is a first step to identify potential reservoirs and habitat interfaces associated with the risk of zoonotic diseases and pathogen spillover.
Proposed Adaptive Control Strategy of Modular Multilevel Converter Based on Virtual Synchronous Generator
Authors: Shi Dao , Lv Ling , Wang Xuesong , Zhang Liang
Published: October 2023

In the context of weak grids, vector-controlled modular multilevel converters (MMC) suffer from issues such as low inertia, low damping, and poor system stability. To address these challenges, this paper proposes a control strategy for virtual synchronous generators (VSGs) based on a fuzzy logic control algorithm. The conFtrol strategy leverages the capability of fuzzy algorithms to handle the fuzziness and uncertainty of input signals, enabling adaptive control of the virtual inertia and damping coefficient of the VSG, thus empowering the system with autonomous frequency and voltage regulation capabilities. When the system deviates from or approaches the stable operating point, increasing or decreasing the virtual inertia allows for dynamic adjustment of the virtual inertia and damping coefficient in response to load fluctuations during MMC operation. Through simulation verification, it is demonstrated that the proposed control method provides inertia support to the system during sudden changes in active load during MMC grid-connected operation. This control method achieves adaptive adjustment of the virtual inertia and damping coefficient, effectively enhancing system stability. The simulation results validate the effectiveness and correctness of the proposed control strategy.
Output Waveform Distortion Suppression Method of Asymmetric Sine Wave Inverter Based on Online Identification and Linearization of System Transmission Characteristics
Authors: Ning Jichao , Ben Hongqi , Li Jinhui , Wang Xuesong , Meng Tao
Published: October 2023

Limited by the switching frequency of an insulated gate bipolar transistor (IGBT), the system bandwidth of high-power inverters is low. If the amplitude and phase changes of each harmonic from the reference signal to the output waveform are defined as transmission characteristics, it can be concluded that the limited bandwidth will result in nonlinear system transmission characteristics. This results in the amplitude and phase distortion of each harmonic of the asymmetric sine wave, which in turn leads to severe distortion of the output waveform. Therefore, this article proposes a method to linearize transmission characteristics. This method effectively offsets the nonlinear effect of transmission characteristics, which is caused by the limited bandwidth, by causing distortions with respect to each harmonic in the reference signal, thereby suppressing the distortion of the output waveform. In addition, an online identification method of transmission characteristics based on a state observer is proposed to achieve the online linearization of system transmission characteristics. This method does not rely on closed-loop system control, has no stability problems, and can be used for a variety of control methods. Simulation and experiments verify the effectiveness of this method.
Boosting the Response of Object Detection and Steering Angle Prediction for Self-Driving Control
Authors: Chang Bao Rong , Tsai Hsiu-Fen , Chang Fu-Yang
Published: October 2023

Our previous work introduced the LW-YOLOv4-tiny and the LW-ResNet18 models by replacing traditional convolution with the Ghost Conv to achieve rapid object detection and steering angle prediction, respectively. However, the entire object detection and steering angle prediction process has encountered a speed limit problem. Therefore, this study aims to significantly speed up the object detection and the steering angle prediction simultaneously. This paper proposes the GhostBottleneck approach to speed the frame rate of feature extraction and add the SElayer method to maintain the existing precision of object detection, which constructs an enhanced object detection model abbreviated as LWGSE-YOLOv4-tiny. In addition, this paper also conducted depthwise separable convolution to simplify the Ghost Conv as depthwise separable and ghost convolution, which constructs an improved steering angle prediction model abbreviated as LWDSG-ResNet18 that can considerably speed up the prediction and slightly increase image recognition accuracy. Compared with our previous work, the proposed approach shows that the GhostBottleneck module can significantly boost the frame rate of feature extraction by 9.98%, and SElayer can upgrade the precision of object detection slightly by 0.41%. Moreover, depthwise separable and ghost convolution can considerably boost prediction speed by 20.55% and increase image recognition accuracy by 2.05%.
Power Generation Calculation Model and Validation of Solar Array on Stratospheric Airships
Authors: Song Kaiyin , Li Zhaojie , Zhang Yanlei , Wang Xuwei , Xu Guoning , Zhang Xiaojun
Published: October 2023

Current stratospheric airships generally employ photovoltaic cycle energy systems. Accurately calculating their power generation is significant for airships’ overall design and mission planning. However, the power generation of solar arrays on stratospheric airships is challenging to model and calculate due to the dynamic nature of the airships’ flight, resulting in continuously changing radiation conditions on the curved surface of the airships. The power generated by the airship solar array was modeled herein through a combination of the flight attitude, spatial position, time, and other influencing factors. Additionally, the model was modified by considering the variation in photovoltaic conversion efficiency based on the radiation incidence angle, as well as the state of charge and power consumption of the energy storage battery pack. This study compared the measurement data of power generation in real flight tests with the calculation results of the model. The comparison showed that the results of the calculated model were highly consistent with the actual measured data. An average normalized root-mean-square error of 2.47% validated the accuracy of the newly built model. The generalizability and rapidity of the model were also tested, and the results showed that the model performed well in both metrics.
Assessment of Wind and Solar Power Potential and Their Temporal Complementarity in China’s Northwestern Provinces: Insights from ERA5 Reanalysis
Authors: Fang Wei , Yang Cheng , Liu Dengfeng , Huang Qiang , Ming Bo , Cheng Long , Wang Lu , Feng Gang , Shang Jianan
Published: October 2023

In the quest to scientifically develop power systems increasingly reliant on renewable energy sources, the potential and temporal complementarity of wind and solar power in China’s northwestern provinces necessitated a systematic assessment. Using ERA5 reanalysis data for wind speed and solar irradiance, an evaluation was carried out to determine the potential and spatial distribution of wind and solar power across these provinces. Land use types and terrestrial surface slopes were considered in gauging this potential. Theoretical wind and solar power outputs were then compared to understand their complementarity on annual, monthly, and hourly temporal scales. This exploration utilized methodologies including rank correlation coefficients, crossover frequency analysis, and standard deviation complementarity rates. Areas such as the Tarim Basin, Jungar Basin, and the northeastern part of Xinjiang, northwestern Qinghai, and northern Gansu were identified as having significant wind and solar power potential, with wind power densities reaching as high as 600 W/m2 and solar irradiance surpassing 2000 kWh/m2. In these energy-rich areas, the distinct complementarity between theoretical wind and solar outputs was discerned. On an annual scale, the complementarity appeared weakest, with only 7.48% of the combined provinces’ area showing medium-level complementarity. On a monthly scale, conversely, a pronounced complementarity was displayed, especially during the March–May and October–November periods. When evaluated on an hourly basis, an impressive 63.63% of the total output duration exhibited complementary characteristics.
Integrated Design and Flight Validation of Solar-Powered Unmanned Aerial Vehicle (UAV) Structure and Propulsion System
Authors: Guo Qing , Qiu Minghao , Li Xiaoqiang , Sun Wen , Guo Zihua
Published: October 2023

The development of solar-powered unmanned aerial vehicles (UAVs) primarily focuses on enhancing the efficiency of the propulsion system to minimize energy consumption during the conversion of valuable solar energy. However, due to the unique nature of UAV propulsion systems, there is limited cross-reference ability among existing solar-powered UAV systems. This paper proposes an integrated design approach for the propulsion system and UAV structure. Based on this approach, an overall design is conducted for the solar-powered UAV, including initial design goals and performance parameters. Aerodynamic layout design and performance estimation are carried out, and a prototype is fabricated and assembled for flight testing validation. The results demonstrate the significant importance of this approach in improving the efficiency of the solar-powered UAV propulsion system.
Compliance-Based Determination of Fatigue Design Curves for Elastomeric Adhesive Joints
Authors: Fernandes Pedro Henrique Evangelista , Nagel Christof , Wulf Andreas , Beber Vinicius Carrillo , Mayer Bernd
Published: October 2023

A compliance-based method for the determination of fatigue design curves for elastomeric adhesive joints is developed and validated. Fatigue experiments are conducted on elastomeric adhesives (a polyurethane and a silane-modified polymer) under different stress ratios (R = 0.1/0.5/−1) and conditions (23 °C/50% r.h. and 40 °C/60% r.h.). The investigation focused on butt and thick adherent shear test joints. Fatigue tests are recorded with cameras to identify the stages of crack initiation and propagation. For each fatigue test, the stiffness and compliance per cycle are calculated until final failure. The proposed method identifies a transition point that distinguishes regions under stable and unstable compliance growth. Fatigue design curves are then built based on the transition point and on the number of cycles to reach different degrees of initial stiffness (90%, 80%, 70% and 60%). The failure ratio, i.e., the lifetime for reaching a given approach divided by the total lifetime, is introduced to evaluate the data in terms of average values and standard deviation. The results indicate that the proposed method can yield fatigue design curves with a high coefficient of determination (accuracy) and high failure ratio (avoiding over-conservative design). Moreover, the method is robust, as the failure ratio for different adhesives, stress ratios, conditions and geometries is highly consistent.
Bioprospecting Plant-Growth-Promoting Endophytic Bacteria Isolated from Moso Bamboo (Phyllostachys edulis) Shoots
Authors: Zhao Aoshun , Ding Xingcui , Huang Manchang , Cheng Yingjie
Published: October 2023

Endophytic bacteria improve plant health and are sometimes necessary to fight against adverse conditions. Bamboo shoots can be eaten as a vegetable and grow into culm wood. However, few studies have focused on the colonization characteristics of endophytic bacteria in Moso bamboo shoots at different tissue sites and different growth developmental phases. Endophytic bacteria were isolated from the top, the base, and the root of Moso bamboo shoots during three different growth and development stages (winter shoot period underground (S1), spring shoot period at 50 cm aboveground (S2), and fast growth shoot period at 200 cm aboveground (S3)), and the highest content of isolable endophytes were in roots in the S3 stage. A total of 253 different endophytic bacteria strains were totally isolated and then evaluated in term of their PGP (plant growth promoting) traits such as inorganic phosphorus solubilization, organic phosphorus solubilization, hormone production, siderophore production, ACC deaminase, and biological nitrogen fixation. Among those newly isolated strains, Pseudomonas rhodesiae RD7-4 had the strongest phosphorus solubilizing ability, Burkholderia pyrrocinia BD24-2 had the strongest nitrogen fixing ability, and Pseudomonas edaphica TD33-1 had the strongest IAA production ability. Inoculation with all three strains significantly increased the content of soluble starch in Arabidopsis, and B. pyrrocinia BD24-2 significantly increased the fresh weight and promoted the growth of the root system. Furthermore, in pot experiments, B. pyrrocinia BD24-2 significantly increased the biomass, root length, and leaf area. Our study contributes to understanding the endophytes in Moso bamboo shoots, and indicates that the strain BD24-2 can be potentially acted as a plant growth promoter.
Variations in the Diversity and Biomass of Soil Bacteria and Fungi under Different Fire Disturbances in the Taiga Forests of Northeastern China
Authors: Cheng Zhichao , Wu Song , Du Jun , Pan Hong , Lu Xinming , Liu Yongzhi , Yang Libin
Published: October 2023

Fire is a crucial disturbance factor for the structure and function of forest ecosystems, as it directly or indirectly affects plant growth, animal life and soil biogeochemical properties. Here, the effects of different fire severities and key driving environmental factors on soil microbial diversity and biomass were investigated in taiga forests that had undergone light, moderate or heavy fires, more recently or in the past, with unburned taiga forest included as a control (CK). The sample sites were located in the Greater Khingan mountains in the northeast of China. Critical soil parameters were determined, and bacterial and fungal content was inferred from determined phospholipid fatty acids (TPLFAs). The results showed that (1) all three fire severities significantly increased the concentrations of soil microbial carbon (MBC), moisture content (MC) and total nitrogen content (TN), but they significantly decreased soil available potassium (AK) content compared with the CK. (2) Recent light and moderate fires significantly decreased the Simpson and Shannon indices of soil microbial communities compared to CK; moderate fire did not change the Menhinick and Margalef indices. (3) Following moderate fire disturbance, there were no significant differences (p > 0.05) in relative abundance of total soil bacteria (Ba), Gram-positive bacteria (G+), Gram-negative bacteria (G−) and content of TPLFAs compared to the control, either as a result of more recent fires or earlier fires. (4) Redundancy analysis revealed that soil MC, TN, soil organic carbon (SOC), available P (AP) and alkaline N (AN) all strongly significantly affected the composition of the microbial communities, with a total explanation of 85.16% of the data. The species diversity and biomass of Ba, G+, G− and TPLFAs were in accordance with the intermediate disturbance hypothesis. The change pattern of soil fungi was in accordance with their own characteristics of reproduction and growth, which was in line with k-selection and ecological countermeasures.