bluuebunny/crossref_metadata_2025 huggingface dataset:
Timing of Deep and REM Sleep Based on Fitbit Sleep Staging in Young Healthy Adults under Real-Life Conditions
Authors: von Gall Charlotte , Holub Leon , Ali Amira A. H. , Eickhoff Simon
Published: March 2024

Sleep timing is controlled by intrinsic homeostatic and circadian components. The circadian component controls the chronotype, which is defined by the propensity to sleep at a particular clock time. However, sleep timing can be significantly affected by external factors such as the morning alarm clock. In this study, we analysed the timing of deep and REM sleep as well as the composition of REM sleep using Fitbit sleep staging in young healthy adults (n = 59) under real-life conditions. Sleep stage percentiles were correlated with the timing of total sleep in time after sleep onset for the homeostatic component and in clock time for the circadian component. Regarding the circadian component, the phase of total sleep is most strongly associated with the phases of early deep sleep and REM sleep. Furthermore, a stronger phase relationship between deep and REM sleep with total sleep is associated with greater consolidation of REM sleep. Chronotype-dependent sleep loss correlates negatively with the strength of the phase relationship between deep sleep and total sleep. In conclusion, the interaction of the circadian component of sleep timing with the timing of sleep stages is associated with REM sleep quality. In particular, the interaction of the circadian component of sleep timing with deep sleep seems to be more vulnerable to external factors.
Narrative Forewarnings: A Qualitative Analysis of the Themes Preceding Disorganized Speech in Schizophrenia
Authors: Bettis Robert J. , Faith Laura A. , Beard Ashlynn M. , Whan Brailee A. , Hegwood Ceouna M. , Monette Mahogany A. , Myers Evan J. , Linton Imani S. , Leonhardt Bethany L. , Salyers Michelle P. , Minor Kyle S.
Published: March 2024

Disorganized speech is a critical barrier to recovery in schizophrenia, with profound negative impacts on one’s ability to engage with the world. Despite the limited efficacy of existing treatments in addressing disorganization, a qualitative analysis of what leads to disorganization in patient narratives has been lacking. This study addresses this gap through inductive thematic analysis of 30 narrative interviews with individuals with schizophrenia, matched based on whether Formal Thought Disorder (FTD) is present. Through this analysis, we identified four core themes (alienation, interpersonal tension, personal benchmarks, and adverse experiences) and eight subthemes. Our findings suggest that disorganization may serve as a protective mechanism against psychological distress and highlight how the severity of FTD influences these themes. Alienation, particularly due to illness-related stigma, emerged more prominently in those with FTD. The themes of personal benchmarks and interpersonal tension pointed towards a heightened sensitivity to social interactions and self-perception among those with schizophrenia. Adverse experiences, encompassing past challenges, suggest a potential link between trauma and symptom exacerbation. Our qualitative analysis of what themes precede disorganized speech has implications for tailoring psychotherapy. By considering an individual’s specific triggers and level of disorganization, therapy may be more effectively targeted to improve recovery-based outcomes. By identifying themes within patient narratives, this study advances our understanding of the qualitative aspects preceding disorganized speech in schizophrenia, paving the way for more personalized and effective recovery-focused interventions.
A Filling Method Based on K-Singular Value Decomposition (K-SVD) for Missing and Abnormal Energy Consumption Data of Buildings
Authors: Su Lihong , Liu Manjia , Ling Zaixun , Gang Wenjie , Zhang Chong , Zhang Ying , Hao Xiuxia
Published: March 2024

Massive data can be collected from meters to analyze the energy use behavior and detect the operation problems of buildings. However, missing and abnormal data often occur for the raw data. Effective data filling and smoothing methods are required to improve data quality before conducting the analysis. This paper introduces a data filling method based on K-SVD. The complete dictionary is trained and then utilized to reconstruct incomplete samples to fill the missing or abnormal data. The impacts of the dictionary size, the data missing continuity, and the sample size on the performance of the proposed method are studied. The results show that a smaller dictionary size is recommended considering the computational complexity and accuracy. The K-SVD method outperforms traditional methods, showing a reduction in the MAPE and CVRMSE by 3.8–5.4% and 6.7–87.8%. The proposed K-SVD filling method performs better for non-consecutive missing data, with an improvement in the MAPE and CVRMSE by 0.1–4% and 5.1–6.7%. Smaller training samples are recommended. The method proposed in this study would provide an effective solution for data preprocessing in building and energy systems.
Determinant Features to Reduce the Infrastructure Gap in Saudi Arabia under a Public–Private Partnership Scheme
Authors: Guerrero Adolfo , Lara-Galera Antonio , Alcaraz Carrillo de Albornoz Vicente , Arévalo Sarrate Carlos
Published: March 2024

Saudi Arabia is forecast to develop a significant number of infrastructure projects, as recorded in its strategy Saudi Vision 2030. To implement this strategy, the country intends to leverage public–private partnerships. This research has various goals. Firstly, it intends to identify the determinant features (DFs) that may facilitate the population of private–public partnership (PPP) infrastructure projects in the Kingdom of Saudi Arabia (KSA) through the opinions of PPP experts. Second, it aims to analyse these opinions through a statistical approach. The research used the following methodologies: the development of a survey amongst sectorial experts, with a total of 45 valid responses; a statistical characterisation of the responses; and an exploratory factor analysis to determine the minimum number of factors explaining the proposed objectives. The findings of the research revealed that the five most relevant factors were the availability and effectiveness of a proper regulatory and legal framework; adequate risk allocation and sharing among project stakeholders; a straightforward project brief and client outcomes; the comprehensive and business viability of project feasibility studies; and finally, the assurance that proper project value management systems are in place during different project stages. As its principal contribution, this study finds, based on the experts’ opinions, that KSA should consider the mentioned determinant factors to ensure that PPP plays the expected role in the provision of infrastructure.
Immuno-Molecular Targeted Therapy Use and Survival Benefit in Patients with Stage IVB Cervical Carcinoma in Commission on Cancer®-Accredited Facilities in the United States
Authors: Sitler Collin A. , Tian Chunqiao , Hamilton Chad A. , Richardson Michael T. , Chan John K. , Kapp Daniel S. , Leath Charles A. , Casablanca Yovanni , Washington Christina , Chappell Nicole P. , Klopp Ann H. , Shriver Craig D. , Tarney Christopher M. , Bateman Nicholas W. , Conrads Thomas P. , Maxwell George Larry , Phippen Neil T. , Darcy Kathleen M.
Published: March 2024

Purpose: To investigate IMT use and survival in real-world stage IVB cervical cancer patients outside randomized clinical trials. Methods: Patients diagnosed with stage IVB cervical cancer during 2013–2019 in the National Cancer Database and treated with chemotherapy (CT) ± external beam radiation (EBRT) ± intracavitary brachytherapy (ICBT) ± IMT were studied. The adjusted hazard ratio (AHR) and 95% confidence interval (CI) for risk of death were estimated in patients treated with vs. without IMT after applying propensity score analysis to balance the clinical covariates. Results: There were 3164 evaluable patients, including 969 (31%) who were treated with IMT. The use of IMT increased from 11% in 2013 to 46% in 2019. Age, insurance, facility type, sites of distant metastasis, and type of first-line treatment were independently associated with using IMT. In propensity-score-balanced patients, the median survival was 18.6 vs. 13.1 months for with vs. without IMT (p < 0.001). The AHR was 0.72 (95% CI = 0.64–0.80) for adding IMT overall, 0.72 for IMT + CT, 0.66 for IMT + CT + EBRT, and 0.69 for IMT + CT + EBRT + ICBT. IMT-associated survival improvements were suggested in all subgroups by age, race/ethnicity, comorbidity score, facility type, tumor grade, tumor size, and site of metastasis. Conclusions: IMT was associated with a consistent survival benefit in real-world patients with stage IVB cervical cancer.
The Impact of Mutational Hotspots on Cancer Survival
Authors: Gonzalez-Cárdenas Melissa , Treviño Víctor
Published: March 2024

Background: Cofactors, biomarkers, and the mutational status of genes such as TP53, EGFR, IDH1/2, or PIK3CA have been used for patient stratification. However, many genes exhibit recurrent mutational positions known as hotspots, specifically linked to varying degrees of survival outcomes. Nevertheless, few hotspots have been analyzed (e.g., TP53 and EGFR). Thus, many other genes and hotspots remain unexplored. Methods: We systematically screened over 1400 hotspots across 33 TCGA cancer types. We compared the patients carrying a hotspot against (i) all cases, (ii) gene-mutated cases, (iii) other mutated hotspots, or (iv) specific hotspots. Due to the limited number of samples in hotspots and the inherent group imbalance, besides Cox models and the log-rank test, we employed VALORATE to estimate their association with survival precisely. Results: We screened 1469 hotspots in 6451 comparisons, where 314 were associated with survival. Many are discussed and linked to the current literature. Our findings demonstrate associations between known hotspots and survival while also revealing more potential hotspots. To enhance accessibility and promote further investigation, all the Kaplan–Meier curves, the log-rank tests, Cox statistics, and VALORATE-estimated null distributions are accessible on our website. Conclusions: Our analysis revealed both known and putatively novel hotspots associated with survival, which can be used as biomarkers. Our web resource is a valuable tool for cancer research.
Longitudinal Muscle Biopsies Reveal Inter- and Intra-Subject Variability in Cancer Cachexia: Paving the Way for Biopsy-Guided Tailored Treatment
Authors: Filis Panagiotis , Tzavellas Nikolaos P. , Stagikas Dimitrios , Zachariou Christianna , Lekkas Panagiotis , Kosmas Dimitrios , Dounousi Evangelia , Sarmas Ioannis , Ntzani Evangelia , Mauri Davide , Korompilias Anastasios , Simos Yannis V. , Tsamis Konstantinos I. , Peschos Dimitrios
Published: March 2024

In the rapidly evolving landscape of cancer cachexia research, the development and refinement of diagnostic and predictive biomarkers constitute an ongoing challenge. This study aims to introduce longitudinal muscle biopsies as a potential framework for disease monitoring and treatment. The initial feasibility and safety assessment was performed for healthy mice and rats that received two consecutive muscle biopsies. The assessment was performed by utilizing three different tools. Subsequently, the protocol was also applied in leiomyosarcoma tumor-bearing rats. Longitudinal muscle biopsies proved to be a safe and feasible technique, especially in rat models. The application of this protocol to tumor-bearing rats further affirmed its tolerability and feasibility, while microscopic evaluation of the biopsies demonstrated varying levels of muscle atrophy with or without leukocyte infiltration. In this tumor model, sequential muscle biopsies confirmed the variability of the cancer cachexia evolution among subjects and at different time-points. Despite the abundance of promising cancer cachexia data during the past decade, the full potential of muscle biopsies is not being leveraged. Sequential muscle biopsies throughout the disease course represent a feasible and safe tool that can be utilized to guide precision treatment and monitor the response in cancer cachexia research.
The Industrial Catalysis Section: A Place to Publish Applied Catalysis Research
Authors: Busca Guido
Published: March 2024

Chemical technologies provide processes for the large-scale production of materials (i [...]
Wear Reduction on the Roller–Shoe Mechanism at High Operation Loads
Authors: Iordache Constantin Răzvan , Bujoreanu Carmen , Alaci Stelian , Ciornei Florina-Carmen , Romanu Ionut-Cristian
Published: March 2024

The roller–shoe mechanism is a classic mechanical assembly with an essential role in motion transmission. Common rail high-pressure pumps are an example of a complex assembly that uses such a mechanism to transform the rotation motion into a translation one. The rolling element of the mechanism is represented by a cylindrical roller. Although it can carry heavy loads due to its design, a proper surface profile could significantly increase the life of the entire mechanism. A better solution can be achieved using a logarithmic profile. The shoe is the second base element of the mechanism. It is a part with an inner cylindrical surface and it is separated from the roller by a thin lubricant film. Considering this, increasing the hardness of the roller–shoe contact surface can be obtained using a suitable coating. The positive results of this coating are highlighted using endurance tests to which high-pressure pumps are subjected. Therefore, the roller profile and the shoe coating represent two directions for improving the contact between the mechanism transmission elements, in terms of wear reduction. The purpose of this paper is to identify a suitable roller profile and to highlight its impact on the shoe coating.
Effect of Sulphate-Reducing Bacteria Activity on the Performance of Thermally Sprayed Aluminium and Polyurethane Coatings
Authors: Santos-Pereda Iñigo , Madina Virginia , Rodriguez Elena , Jorcin Jean-Baptiste , Acha Esther
Published: March 2024

In the present work, we studied whether the exposure of synthetic seawater with anaerobic sulphate-reducing bacteria (SRB) on some steel samples generates a bacterial biofilm in their surfaces. Bare steel belonging to a mooring chain as well as two coating systems applied on the steel surface were studied: polyurethane (PU) and thermally sprayed aluminium (TSA) with and without an epoxy-based sealant. After 30 days of immersion in SRB-inoculated synthetic seawater, a bacterial count was attained, and the samples were observed using scanning electron microscopy (SEM) and locally analysed using X-ray scattered energy spectroscopy (EDS). A biofilm developed on every tested surface (continuous or in the form of pustules), with evidence of metabolic activity of the SRB. Finally, a mechanism of degradation for TSA in the presence of SRB is proposed for environments with a high concentration of bacteria.
Binder-Free Two-Dimensional Few-Layer Titanium Carbide MXene Ink for High-Performance Symmetric Supercapacitor Device Applications
Authors: Thirumal Vediyappan , Rajkumar Palanisamy , Kim Jin-Ho , Babu Bathula , Yoo Kisoo
Published: March 2024

A heightened interest in developing MXene (Ti3C2Tx) for energy storage is evident in binder-free MXene ink being directly applied to current collector Ni-foam. Moreover, 2D titanium carbide MXene, with a few layers of nanostructure, has been prepared for symmetric supercapacitor device applications. As-prepared MXene nanosheets exist in two forms: dried powder and ink, achieved through wet-chemical etching and dimethyl sulfoxide delamination from the MAX (Ti3AlC2) phase. This comparative study of electrode devices involves (i) MX-dry powder with binder/additive electrodes and (ii) binder-free MXene inks with directly applied MX-conductive inks. The surface morphological images of pure MX-powder/ink display few layers, and material analysis reveals the good crystalline nature of delaminated MXene (Ti3C2Tx) inks. The electrochemical symmetric supercapacitor device performances of pure MXene powder and binder-free directly applied/coated MXene (Ti3C2Tx) ink, in terms of cyclic voltammetry (CV) and impedance spectroscopy (EIS), exhibit galvanostatic charge–discharge (GCD) curves that show high specific capacitance (Csp) at 105.75 F/g at a current density of 1 A/g. A comparison of active material electrodes demonstrated excellent cycle stability. Hence, in this work, we confirmed the superior capacitive behavior of binder-free MXene ink (MX-I) compared to conductive additives with polymeric binders included in MXene electrodes.
The Potential of Foraging Chacma Baboons (Papio ursinus) to Disperse Seeds of Alien and Invasive Plant Species in the Amathole Forest in Hogsback in the Eastern Cape Province, South Africa
Authors: Pamla Lwandiso , Vukeya Loyd R. , Mokotjomela Thabiso M.
Published: March 2024

The invasion of alien and invasive plants into the threatened Amathole Forest in Hogsback, Eastern Cape Province (South Africa) is an emerging priority conservation issue. The objective of this pilot study was to document and compare the foraging visits of two chacma baboon (Papio ursinus) troops in their natural and human habitats and their foraging behavioural activities to understand their potential to disperse ingested alien seeds in Hogsback. We also estimated the number of seeds per faecal sample collected from the foraging trails of the two troops of baboons, and determined potential dispersal distances using allometric equations. Since the focal troops used preferred sleeping and foraging sites, we predicted that these sites would have a high concentration of propagules. We applied the normalised difference vegetation index (NDVI) to discern possible vegetation cover changes. Overall, the two chacma baboon troops showed a similar number of daily foraging visits, although they preferred to forage more in human-modified than natural habitats. Their feeding and moving activities were significantly greater than other activities recorded during the study. There were significant differences in the numbers of seeds of six different fruiting plant species: 82.2 ± 13.3% (n = 284) for Acacia mearnsii; 78.9 ± 12.1% (n = 231) for Pinus patula, and 64.0 ± 20.0% (n = 108) for Solanum mauritianum. The two baboon troops could transport about 445 536 seeds from the six focal fruiting plant species considered in this study. Baboons’ seed dispersal distances were long at > 5 km per daily foraging activity. The NVDI vegetation cover analysis (i.e., 1978–2023) shows that the dense vegetation cover expanded by 80.9 ha, while the moderate and sparse vegetation cover collectively decreased by 10.3 ha. Although the seed dispersal pattern was neither clumped nor displayed any recognisable pattern, against our prediction, the number of faecal samples containing alien seeds and the observed foraging movement patterns suggest that chacma baboons disperse alien plant seeds that may establish and facilitate the deterioration of the natural forest. Further quantitative studies investigating the diversity of the plant species dispersed, their germination rates after ingestion by baboons, and their seasonal patterns are required to understand the baboon seed dispersal systems in the Amathole forests of Hogsback.
Giant Lipoma of the Bauhin’s Valve
Authors: Fugărețu Cosmina , Misarca Catalin
Published: March 2024

Lipomas are benign tumors that can affect the digestive tract, everywhere from the hypopharynx to the rectum. Lipomas affecting the large intestine are the second most common benign tumor, after colon adenoma. We present the case of a 46-year-old patient who was initially hospitalized in the Gastroenterology Clinic with a diagnosis of gastrointestinal bleeding. The colonoscopy raised the suspicion of a malignant tumor of the transverse colon, but the computed tomography scan showed the existence of a lipoma that measured 16/11/12 cm that occupied the ascending and transverse colon, though the CT examination could not determinate the origin of the lipoma. After restoring the hydro-electrolytic and fluid balance of the patient, surgery was performed and a huge lipoma of the ileocecal valve was discovered. Extended right hemicolectomy was performed, with good subsequent postoperative recovery of the patient, who was discharged on the fifth day after the surgery. The peculiarity of this case is the huge size of the benign tumor. Lipomas with digestive system localization, although rare, must be considered in patients arriving at the Emergency Department with digestive hemorrhages, intussusception and even intestinal obstruction.
Hangeshashinto-Associated Mesenteric Phlebosclerosis and Highly Atypical Adenoma Requiring Laparoscopic Right Hemicolectomy
Authors: Nishiwaki Ryo , Inoue Yasuhiro , Sugao Masataka , Sugimasa Natsuko , Hamaguchi Tetsuya , Noji Midori , Takeuchi Kenji , Ito Yoshiyuki , Kato Toshio , Yasuma Taro , D’Alessandoro-Gabazza Corina N. , Gabazza Esteban C. , Imoto Ichiro
Published: March 2024

Mesenteric phlebosclerosis is a rare ischemic colonic disorder caused by impaired venous drainage. Its prevalence is higher in East Asia, where herbal medicine is widely used. Treatment remains controversial. A 76-year-old woman who had taken Hangeshashinto, an herbal medicine, for 11 years was admitted for endoscopic treatment of high-grade dysplasia in the ascending colon. She had diarrhea and mesenteric phlebosclerosis diagnosed by abdominal computed tomography at age 71. At age 75, small polyps were detected in the ascending colon. A subsequent study revealed an increase in polyp size to 15 mm. Endoscopic mucosal resection failed to remove the lesion. A biopsy showed high-grade dysplasia with possible colon cancer risk. Conservative therapy did not improve mesenteric phlebosclerosis-related diarrhea; therefore, a laparoscopic right hemicolectomy was performed. Intraoperatively, the cecum was adherent to the abdominal wall and the right ovary. The specimen showed high-grade dysplasia in the mucosa and severe submucosal fibrosis. No metastasis was observed. This case shows the link between mesenteric phlebosclerosis and high-grade dysplasia in the ascending colon. Endoscopic mucosal resection was unsuccessful in removing the tumor. Endoscopic submucosal dissection was an alternative, but its safety in mesenteric phlebosclerosis-affected colonic segments remains uncertain. A laparoscopic right hemicolectomy was performed.
Enhancing Education in Elementary Schools through Gamified Learning: Exploring the Impact of Kahoot! on the Learning Process
Authors: Rayan Baraa , Watted Abeer
Published: March 2024

The integration of technology in educational settings has gained popularity, aiming to enhance student engagement and motivation. Kahoot! digital tool activities have emerged as a favored choice for creating dynamic and captivating learning environments. This study investigates the impact of incorporating Kahoot! on students’ learning outcomes and motivation to learn science. The research utilized a quantitative methodology, collecting data through pre- and post-questionnaires administered to both experimental (N = 53) and control groups (N = 56). This study identified that integrating Kahoot! activities led to a significant improvement in students’ grasp of scientific concepts and principles. Moreover, a noteworthy increase in self-efficacy, interest, and enjoyment levels was observed among students in the experimental groups. This indicates that Kahoot! activities not only enhance students’ understanding of scientific concepts but also amplify their motivation to engage with the subject matter. This study also explored potential demographic variables that could influence these outcomes. Notably, the findings suggest that grade level plays a role in students’ motivation to learn science. In conclusion, this study underscores the potential of Kahoot! activities to positively influence students’ science learning experiences, emphasizing the importance of cultivating dynamic and captivating learning environments.
The Effect of Visual Reasoning on Arithmetic Word Problem Solving
Authors: Purcar Ana-Maria , Bocoș Mușata , Pop Alexandra-Lucia , Roman Alina , Rad Dana , Mara Daniel , Crișan Claudia , Răduț-Taciu Ramona , Mara Elena-Lucia , Todor Ioana , Muntean-Trif Letiția , Neacșu Mihaela-Gabriela , Costache Colareza Corina , Maier Monica , Tăușan-Crișan Liana , Triff Zorica , Baciu Ciprian , Marin Diana-Crina , Triff Dorin-Gheorghe
Published: March 2024

First-grade students often encounter challenges in understanding and solving arithmetic word problems due to their limited reading comprehension abilities. Despite these difficulties, students may employ arbitrary strategies, such as combining numbers based on specific keywords, even if they lack a full understanding of the problems. Research suggests that effective mathematical reasoning involves the use of visual mental representations during the problem-solving process. To address this, some studies have explored methods to enhance students’ comprehension of word problems. Building on this, the current study explores the impact of first-grade pupils creating visual representations of problem situations on their comprehension and the number of correct solutions. In a typical math class, 45 first graders received a paper-and-pencil task, and, in a visual context, they solved similar problems after reading and illustrating the situation. The findings reveal that while most participants correctly represented the problem situations through drawing, about half struggled to determine the numeric solutions. Nevertheless, the visual context led to an increase in the number of correct problem solutions compared to the normal context, suggesting the potential benefits of incorporating visual representations in enhancing comprehension and problem-solving skills.
A Behavior Model of SiC DMOSFET Considering Thermal-Runaway Failures in Short-Circuit and Avalanche Breakdown Faults
Authors: Wu Yifan , Li Chi , Zheng Zedong , Wang Lianzhong , Zhao Wenxian , Zou Qifeng
Published: March 2024

Accurate fault simulation and failure prediction have long been challenges for SiC MOSFETs users. This paper presents a behavior model of Silicon Carbide (SiC) double-implanted MOSFET (DMOSFET), considering thermal-runaway failures in short-circuit and avalanche breakdown faults on the basis of cell-level physical processes. The proposed model can simulate the faults with extremely high accuracy and precisely predict SiC DMOSFET’s short-circuit withstand time and critical avalanche energy. By finite-element simulations, cell-level physical processes of short-circuit and avalanche breakdown faults are clarified. The mechanisms of thermal-runaway failures are deeply discussed with references to existing studies. Based on semiconductor and device physics mechanisms, the proposed model is constructed upon a traditional behavior model of SiC MOSFET with several parallel branches that are proposed to describe the thermal-runaway failures during both faults. The Cauer thermal network model is used for estimating junction temperature within it. The proposed model is constructed in Simulink, and it is validated using short-circuit and unclamped inductive switching (UIS) tests.
Compact Four-Port Waveguide Circulator Using Discrete Ferrites for Injection-Locking Magnetron System
Authors: Mi Chaguo , Zhao Chaoxia , Liu Zhenlong , Luo Tingfang , Huang Chao , Agrawal Dinesh K. , Zhang Yi , Huang Kama
Published: March 2024

A compact high-power four-port circulator aiming to simplify the conventional, complex, and bulky injection-locking magnetron system is proposed. To reduce the performance deterioration and the risk of ferrite rupture under long-term high-microwave-power condition, the method of breaking a monolithic ferrite into three discrete ferrites in a conventional three-port circulator is proposed. To miniaturize the size and cost of the four-port circulator, a butterfly-shaped waveguide structure is proposed, with a stub inserted into the cavity at the central point and with no connecting waveguide. Multiphysics simulation results show that the temperature coefficient of variation (COV) at the surface of the discrete ferrites is 12.4% lower than that of a monolithic ferrite circulator, with input microwave power of 10 kW. The size of the proposed four-port waveguide circulator is 27% less than the assembly of two three-port circulators, and way smaller than a conventional differential phase shift circulator (DPSC). The simulated and measured S-parameters match well, and the measured power capacity of the fabricated circulator is higher than 3 kW (limited by the experimental condition). A magnetron is successfully locked using only one designed compact circulator. The research in this paper promotes the development of injection-locking magnetron and provides a design example for the compact, high-power circulator.
Exploration- and Exploitation-Driven Deep Deterministic Policy Gradient for Active SLAM in Unknown Indoor Environments
Authors: Zhao Shengmin , Hwang Seung-Hoon
Published: March 2024

This study proposes a solution for Active Simultaneous Localization and Mapping (Active SLAM) of robots in unknown indoor environments using a combination of Deep Deterministic Policy Gradient (DDPG) path planning and the Cartographer algorithm. To enhance the convergence speed of the DDPG network and minimize collisions with obstacles, we devised a unique reward function that integrates exploration and exploitation strategies. The exploration strategy allows the robot to achieve the shortest running time and movement trajectory, enabling efficient traversal of unmapped environments. Moreover, the exploitation strategy introduces active closed loops to enhance map accuracy. We conducted experiments using the simulation platform Gazebo to validate our proposed model. The experimental results demonstrate that our model surpasses other Active SLAM methods in exploring and mapping unknown environments, achieving significant grid completeness of 98.7%.
Research on Flutter Characterization of Flexible Blade Response under Typhoon Operating Conditions
Authors: Liu Huiyuan , Han Qiaoli , Tian De , Feng Xiaomei , Guo Zhiyong , Zhang Minghui
Published: March 2024

Wind turbine blades, being flexible, are susceptible to damage during typhoons. Studying the aeroelastic response of these blades in typhoon conditions is crucial for providing a theoretical foundation for their optimization and design. This research focuses on the NREL 5 MW flexible blade, employing the B-L stall model for dynamic inflow and geometrically exact beam theory to develop an aeroelastic model capable of predicting the blade’s flutter limit. Through quantitative analysis, we assess the stability of the wind turbine’s flexible blade under typhoon conditions and examine the blade tip’s transient response. The findings indicate that the model’s flutter speed is 21.5 rpm, marked by a significant increase in tip deflection’s mean square error of over 80% and a coupling of flapwise and torsional modes at 4.81 Hz. The blade tip’s transient response under typhoon conditions does not satisfy the flutter criterion, thus preventing instability. Under typhoon conditions, the deflection in the flapwise, edgewise, and twist directions of the blade shows an increase of 12.1%, 10.5%, and 119.2%, respectively, compared to standard operating conditions.
Load Calculation and Strength Analysis of the Deepwater Landing Drill Pipe-Lowering Operation
Authors: He Guolei , Wang Linqing , Wang Jiarui , Shen Kaixiang , Xiang Hengfu , Wang Jintang , Chen Haowen , Xu Benchong , Qin Rulei , Yin Guole
Published: March 2024

A landing string is directly exposed to seawater and subjected to significant stresses and complex deformations due to environmental loads such as wind, waves, and ocean currents during the phase in which the drill string carries the casing to the wellhead. Meanwhile, as the water depth increases, the weight of the drill string increases, leading to an increase in the tensile loads borne by the drill string, which can easily cause a risk of failure. Therefore, a quasi-static load calculation model for the deepwater insertion of the pipe column was established. Using the Ansys platform, simulations were conducted for average wind, wave, and ocean current conditions during different months throughout the year. The ultimate loads and stress distributions of the string were derived from theoretical analyses and numerical simulations for different operational sea states, and the suggested safe operating window and desired BOP trolley restraining reaction force for landing strings’ lowering are given according to the existing industry standards. The research findings can help in identifying the potential risks and failure modes of the deepwater landing string under different working conditions.
Geological Constraints on the Gas-Bearing Properties in High-Rank Coal: A Case Study of the Upper Permian Longtan Formation from the Songzao Coalfield, Chongqing, Southwest China
Authors: Chen Dishu , Wang Jinxi , Tian Xuesong , Guo Dongxin , Zhang Yuelei , Zeng Chunlin
Published: March 2024

The Permian Longtan Formation in the Songzao coalfield, Southwest China, has abundant coalbed methane (CBM) stored in high-rank coals. However, few studies have been performed on the mechanism underlying the differences in CBM gas content in high-rank coal. This study focuses on the characterization of coal geochemical, reservoir physical, and gas-bearing properties in the coal seams M6, M7, M8, and M12 based on the CBM wells and coal exploration boreholes, discusses the effects of depositional environment, tectono-thermal evolution, and regional geological structure associated with CBM, and identifies major geological constraints on the gas-bearing properties in high-rank coal. The results show that high-rank coals are characterized by high TOC contents (31.49~51.32 wt%), high Tmax and R0 values (averaging 539 °C and 2.17%), low HI values (averaging 15.21 mg of HC/g TOC), high porosity and low permeability, and high gas-bearing contents, indicating a post-thermal maturity and a good CBM production potential. Changes in the shallow bay–tidal flat–lagoon environment triggered coal formation and provided the material basis for CBM generation. Multistage tectono-thermal evolution caused by the Emeishan mantle plume activity guaranteed the temperature and time for overmaturation and thermal metamorphism and added massive pyrolytic CBM, which improved the gas production potential. Good geological structural conditions, like enclosed fold regions, were shown to directly control CBM accumulation.
Endogenous Phytohormone and Transcriptome Analysis Provided Insights into Seedling Height Growth of Pinus yunnanensis
Authors: Lu Zhuangyue , Wang Qibo , Yang Zhenxin , Chen Lin , Cai Nianhui , Xu Yulan
Published: March 2024

Plant height plays a crucial role in both the structure and quality of plants. Pinus yunnanensis is a distinctive species of the forest found in Southwest China, where the height of the plants significantly influences both yield performance and plant architecture. Although the phenotypes of P. yunnanensis seedlings with different plant heights were quite different at their seedling stage, the molecular mechanisms controlling the seedling differentiation remain poorly understood. This study is aimed to investigate the underlying mechanisms of P. yunnanensis seedling differentiation using phenotypic, transcriptomic, and endogenous phytohormone analyses. The P. yunnanensis seedlings were categorized into three grades, i.e., Grades A, B, and C, by mean ± 1/2 standard deviation method (H ± 1/2σ), and the seedling height and ground diameter were measured. We conducted the measurements of endogenous hormone levels in the young shoot apexes of seedlings at different grades during the fast-growth period (March). The DEGs were identified through transcriptome sequencing and analyzed by qRT-PCR validation. Significant differences were observed in the content and ratio of endogenous phytohormones among various grades of P. yunnanensis seedlings (p < 0.05). The ABA content in Grade A was prominently more than that in Grades B and C, and the order of the content of auxins was Grade B > C > A. Furthermore, when compared to Grade A, the ratios of auxins/CTKs, auxins/ABA, CTKs/ABA, and (auxins + CTKs)/ABA exhibited significant increases in Grades B and C. Moreover, GO functional annotation analysis indicated the more pronounced enrichment of DEGs in molecular functions. KEGG metabolic pathway analysis revealed notable differences in enrichment pathways between the pairwise comparisons. The “plant hormone signal transduction” pathway exhibited enrichment in the two groups, followed by “plant–pathogen interaction” pathway in the organism system that was enriched in the three groups. In addition, the results for endogenous phytohormone metabolism pathways indicate a significant up-regulation in the expression of AUX1, while AHP and PP2C exhibited significant down-regulation. To sum up, we aimed at investigating the underlying mechanisms of P. yunnanensis seedling differentiation using phenotypic, transcriptomic, and endogenous phytohormone analyses. The results suggested that individual phytohormones have a limited capacity to regulate gene expression, and seedling differentiation results from the combined regulation of multiple hormones. In addition, several candidate genes associated with phytohormone biosynthesis and signal transduction pathways were identified, including AUX1, GH3, AHP, B-ARR, PP2C, etc., which provided candidate genes for the following hormone-related gene overexpression and knockout experiments. These findings provide insights into the molecular genetic control of seedling height growth of P. yunnanensis.
Decomposition and Carbon and Nitrogen Releases of Twig and Leaf Litter Were Inhibited by Increased Level of Nitrogen Deposition in a Subtropical Evergreen Broad-Leaved Forest in Southwest China
Authors: Song Yali , Xing Jinmei , Hu Chun , Song Chenggong , Wang Qian , Wang Shaojun
Published: March 2024

Atmospheric nitrogen (N) deposition has rapidly increased due to anthropogenic activities, which can exert a crucial effect on biochemical cycling process such as litter decomposition in the subtropical forests. However, the is still uncertainty about the knowledge of N deposition in regulating nutrient release from the leaf and twig litter. For this study, a 2 yr litterbag decomposition experiment was conducted under three levels of N addition treatments in a subtropical evergreen broad-leaved forest, in southwest China. This study aimed to identify the effects of low (LN: 10 g·N·m−2·y−1), medium (MN: 20 g·N·m−2·y−1), and high N addition (HN: 25 g·N·m−2·y−1) on litter decomposition and nutrient release from leaves and twigs. We observed that there was significantly lower litter decomposition (8.13%–13.86%) and nutrient release (7.24%–36.08%) in the HN treatment compared to the LN treatment. The decay of mass, lignin, and cellulose and the nutrient release were faster in leaf litter than in twig litter after N addition (p < 0.05). The ratios of C/phosphorus (P), C/N, and N/P were also significantly greater in twig litter than in leaf litter. Furthermore, the N addition treatments resulted in higher contents of the mass, lignin, and cellulgapose remaining in leaf and twig litter compared to the control (CK). The amount of C, N, and P remaining in leaf (51.4%–59.1%) and twig (44.1%–64.8%) debris was significantly higher in the N treatment compared to CK treatment (p < 0.05). In addition, the litter C/N and C/P were smaller and the litter N/P was larger for each N treatment compared to CK (p < 0.05). The results suggest that N inputs restrain lignin and cellulose degradation and C and N release, and increase the N/P ratio that limits P release in litter. These effects vary with the level of N treatments.
Using Essential Oils to Reduce Yersinia enterocolitica in Minced Meat and in Biofilms
Authors: Vidaković Knežević Suzana , Knežević Slobodan , Vranešević Jelena , Milanov Dubravka , Ružić Zoran , Karabasil Nedjeljko , Kocić-Tanackov Sunčica
Published: March 2024

Yersiniosis, one of the leading foodborne infections in the European Union, is caused by Yersinia enterocolitica. In this study, the antibacterial and antibiofilm effects of cinnamon (Cinnamomum zeylanicum Nees), clove (Syzygium aromaticum L.), oregano (Origanum vulgare L.), rosemary (Rosmarinus officinalis L.), thyme (Thymus vulgaris L.), and winter savory (Satureja montana L.) essential oils were investigated against Y. enterocolitica strains belonging to the bioserotype 4/O:3. Cinnamon essential oil showed the highest antibacterial activity, with an MIC value 0.09 µL/mL, followed by oregano and thyme essential oils, with MIC values from 0.09 to 0.18 µL/mL, and from 0.18 to 0.23 µL/mL, respectively. Thyme essential oil at 0.23 µL/g (MIC) and at 0.46 µL/g (2MIC) significantly (p < 0.05) reduced the number of Y. enterocolitica by 0.38 log CFU/g and 0.64 log CFU/g, respectively, in minced pork meat during storage at 4 °C for 4 days. The Y. enterocolitica strains formed biofilms at 15 °C and 37 °C in tryptic soy broth and Luria–Bertani broth, while no biofilms were obtained at 5 °C, and in meat broth nutrient media. Applying the minimum bactericidal concentrations of cinnamon, clove, oregano, rosemary, thyme, and winter savory essential oils on preformed biofilms led to significant reductions being observed in the range from 45.34% to 78.89%. A scanning electron microscopy assay showed the devastating impact of oregano and thyme essential oils on the morphology of Y. enterocolitica bacterial cells. In conclusion, the results of this study show that essential oils possess high anti-Yersinia and antibiofilm effects.
Synchronous Front-Face Fluorescence Spectra: A Review of Milk Fluorophores
Authors: Freire Paulina , Zamora Anna , Castillo Manuel
Published: March 2024

Milk is subjected to different industrial processes, provoking significant physicochemical modifications that impact milk’s functional properties. As a rapid and in-line method, front-face fluorescence can be used to characterize milk instead of conventional analytical tests. However, when applying fluorescence spectroscopy for any application, it is not always necessary to determine which compound is responsible for each fluorescent response. In complex matrixes such as milk where several variables are interdependent, the unique identification of compounds can be challenging. Thus, few efforts have been made on the chemical characterization of milk’ fluorescent spectrum and the current information is dispersed. This review aims to organize research findings by dividing the milk spectra into areas and concatenating each area with at least one fluorophore. Designations are discussed by providing specific information on the fluorescent properties of each compound. In addition, a summary table of all fluorophores and references cited in this work by area is provided. This review provides a solid foundation for further research and could serve as a central reference.
Investigating Associations between HLA-DR Genotype, H. pylori Infection, and Anti-CagA IgA Seropositivity in a Turkish Gastritis Cohort
Authors: Karataş Lokman , Tatar Zeynep , James Eddie A. , Colakogullari Mukaddes
Published: March 2024

Helicobacter pylori (H. pylori) is associated with gastric inflammation and mucosal antibodies against its cytotoxin-associated gene A (CagA) are protective. Vaccine-elicited immunity against H. pylori requires MHC class II expression, indicating that CD4+ T cells are protective. We hypothesized that the HLA-DR genotypes in human populations include protective alleles that more effectively bind immunogenic CagA peptide fragments and susceptible alleles with an impaired capacity to present CagA peptides. We recruited patients (n = 170) admitted for gastroendoscopy procedures and performed high-resolution HLA-DRB1 typing. Serum anti-CagA IgA levels were analyzed by ELISA (23.2% positive) and H. pylori classified as positive or negative in gastric mucosal tissue slides (72.9% positive). Pearson Chi-square analysis revealed that H. pylori infection was significantly increased in DRB1*11:04-positive individuals (p = 0.027). Anti-CagA IgA was significantly decreased in DRB1*11:04 positive individuals (p = 0.041). In contrast, anti-CagA IgA was significantly increased in DRB1*03:01 positive individuals (p = 0.030). For these HLA-DRB1 alleles of interest, we utilized two in silico prediction methods to compare their capacity to present CagA peptides. Both methods predicted increased numbers of peptides for DRB1*03:01 than DRB1*11:04. In addition, both alleles preferred distinctively different CagA 15mer peptide sequences for high affinity binding. These observations suggest that DRB1*11:04 is a susceptible genotype with impaired CagA immunity, whereas DRB1*03:01 is a protective genotype that promotes enhanced CagA immunity.
Impact of Work–Life Balance on the Quality of Life of Spanish Nurses during the Sixth Wave of the COVID-19 Pandemic: A Cross-Sectional Study
Authors: Antolí-Jover Ana María , Álvarez-Serrano María Adelaida , Gázquez-López María , Martín-Salvador Adelina , Pérez-Morente María Ángeles , Martínez-García Encarnación , García-García Inmaculada
Published: March 2024

This study addresses the health-related quality of life (HRQoL) of Spanish nurses during the sixth wave of the COVID-19 pandemic, assessed through the EQ-5D and EQ-VAS indices. Methods: This cross-sectional 334 study used online surveys, recruiting 305 Spanish nurses. Results: Nurses generally perceived a good HRQoL. “Negative work–family interaction” is adversely associated with the EQ-VAS (β = −0.337, 95% CI [−1.733, −0.723]) and EQ-5D (β = −0.399, 95% CI [−0.021, −0.01]) indices, while “positive work–family interaction” shows a positive relationship with the EQ-VAS (β = 0.218, 95% CI [0.381, 1.759]). The presence of a “paid supportive caregiver” is positively associated with the EQ-VAS (β = 0.18, 95% CI [1.47, 12.3]) and EQ-5D (β = 0.149, 95% CI [0.004, 0.117]) indices, but a higher “number of children” is negatively linked with the EQ-5D index (β = −0.146, 95% CI [−0.061, −0.002]). In addition, living with a partner (EQ-VAS β = 0.16, 95% CI [1.094, 14.67] and EQ-5D index β = 0.174, 95% CI [0.018, 0.163]) and working a “rotating shift” (EQ-5D index β = 0.158, 95% CI [0.005, 0.098]) are positively associated. Conclusions: These findings highlight the need to comprehensively address nurses’ well-being, considering both their working conditions and their home environment, especially in crisis contexts such as the current pandemic.
Oral Health-Related Quality of Life in Italian Children and Adolescents Living with Bone Dysplasia: A Cross-Sectional Study
Authors: Defabianis Patrizia , Ninivaggi Rossella , Tessaris Daniele , Bocca Norma , Romano Federica
Published: March 2024

Bone dysplasia (BD) refers to a group of rare disorders characterized by skeletal and dental anomalies which may negatively influence oral health-related quality of life (OHRQoL). The aim of this cross-sectional study was to assess the impact of BD on OHRQoL in Italian children and adolescents and to assess whether gender and age influence their OHRQoL. A total of 40 patients with BD and 40 age- and gender-matched controls (aged 8–14 years) were asked to complete the Oral Health Impact Profile-14 (OHIP-14), Child Oral Health Impact Profile (COHIP), and the short form of the Child Perceptions Questionnaire (SF-CPQ). Children with BD showed statistically significant lower overall scores of all the questionnaires than the controls (all p < 0.001), with the largest differences being detected in overall symptoms, functional well-being, and social well-being domains. While no statistically significant gender-related differences were observed, adolescents aged 11–14 years experienced worse perception in the emotional and social well-being SSF-CPQ domains (p = 0.042 and p = 0.045, respectively) and in the peer interaction COHIP domain (p = 0.011) compared to the younger age group. Based on these findings, children suffering from BD experience poorer OHRQoL than their healthy peers, suggesting that oral and dental issues may be of special importance for the socio-psychological well-being of these growing individuals.