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Abstract In terms of the characteristics of multi‐objective and interactions among optimization objectives of the tubular permanent magnet linear generator with 120° phase belt toroidal winding (120°‐TPMLG), a multi‐objective optimization method is proposed to improve the generators performances, which is based on the combination of response surface method and the genetic algorithm. First, the sensitivity analysis of different structural parameters on the performances of the 120°‐TPMLG is conducted to pick out the sensitive structural parameters. Then develop those sensitive parameters as optimization variables to establish the response surface equation of the generator performances including output power (P), detent force (F), and the efficiency (η). Subsequently, based on the surface equation, the genetic algorithm (GA) fitness function is proposed to conducted the global optimization and the optimization results are finally obtained. To verify the effectiveness of the proposed optimization method, the performances of the optimal 120°‐TPMLG are analysed and compared with the initial one. The results show that the performances including the detent force and power density of the 120°‐TPMLG are greatly improved, which prove that the proposed multi‐objective optimization method is effective for the 120°‐TPMLG.

Abstract The three‐phase permanent magnet synchronous motor (three‐phase PMSM) has gained much popularity in many applications due to its various advantages. In addition, due to the good fault tolerance, simple inverter circuit structure and high torque density, the six‐phase PMSM has better prospects than three‐phase PMSM in biomedical devices, electric vehicles and other fields with high reliability requirements. In this study, a six‐phase axial‐flux PMSM inherently without cogging torque is proposed to improve torque density, which equips the 60° phase‐belt toroidal winding (60°TW) and slotless stator core. Based on the same effective volume, permanent magnet material, power grade and the other major motor parameters, two six‐phase PMSMs with 30° phase‐belt toroidal winding (30°TW) and 60°TW are designed, respectively. The armature reaction field, air gap magnetic density, back‐electromotive force, output torque, loss characteristic and torque‐speed characteristic are compared by using three‐dimensional (3D) finite‐element models in detail. Finally, the experimental test is carried out using the prototype of three‐phase PMSM with 120° phase‐belt toroidal winding. The experimental results indirectly verify the feasibility of 60° phase‐belt toroidal winding and correctness of 3D FEM. The 3D FEM analysis results are presented to show that torque density of the proposed six‐phase PMSM with 60°TW is improved in comparison to the six‐phase PMSM with 30°TW. Index Terms—60° phase‐belt toroidal winding, axial flux, six‐phase permanent magnet synchronous motor, torque density

Double-sided permanent magnet linear synchronous machine with 120° phase belt toroidal windings (120°-TWDSPMLSM) suffers from large detent force due to the end effect and slot effect. Many existing methods can reduce the detent force of the 120°-TWDSPMLSM effectively. But they also minimize the back electromotive force (back-EMF) and thrust simultaneously. To alleviate this problem, this paper adopts a method of combining slot-shift structure with rearranging the 120° phase belt toroidal windings (120°-TW) to suppress the detent force and improve the back-EMF and thrust of the 120°-TWDSPMLSM simultaneously. First, the slots on the two sides of the primary part are stagger by an optimal distance to reduce the detent force. The models of the detent force, including the end force and cogging force, is established theoretically, and then verified by finite-element analysis (FA). Then, the 120°-TW are rearranged to improve the back-EMF and average thrust. And the electromagnetic characteristics of the 120°-TWDSPMLSM under different shifted distances are analyzed and compared in detail. Finally, the result shows that the detent force of optimized machine is 70.19% lower than that of the original machine, and the thrust fluctuation reduces 19.21%. Besides, the back-EMF of optimized machine is 6.84% lower than that of the original machine, but 31.86 higher than the machine with shifting slots and without rearranging the 120°-TW. Therefore, the optimal method in this paper is available in the detent force reduction and thrust improvement of the 120°-DSPMLSM.

Traditional Se (selenium) fertilizers are poorly deposited on crop leaves and are easily washed away by rain; these factors limit plant Se absorption and pose potential environmental risks. To address this issue, a thermosensitive Se nanoparticles gel (CS-FA/BP-SeNPs) based on chitosan-ferulic acid (CS-FA) and β-glycerophosphate (β-BP) was developed to increase rain-washing resistance and Se uptake in grape leaves. The CS-FA derivative was synthesized via an amide reaction between chitosan and ferulic acid(1:2); this derivative demonstrated strong antibacterial and antioxidant activity, effectively dispersing the Se nanoparticles (SeNPs) and preventing their aggregation. β-glycerophosphate neutralized the pH value of the CS-FA/SeNPs solution, significantly increasing the stability of the SeNPs (stable for 30 days). Up to 37 °C, the solution rapidly formed a hydrogel, increasing its viscous modulus by 5.1 times and improving adhesion. Compared with SeNPs alone, CS-FA/BP-SeNPs showed superior spreading, reducing droplet splashing and retraction. In simulated rainfall experiments, the CS-FA/BP-SeNPs gel coating retained 91.1 % of the material on the leaf surface, while the corresponding value for SeNPs was 13.6 %, demonstrating excellent rainfastness in the former. In open-field cultivation trials, grape leaves treated with the CS-FA/BP-SeNPs gel coating presented a 141.3–192.7 % increase in the Se retention rate and a 51.3–62.3 % increase in Se uptake than those with SeNPs alone. Additionally, CS-FA/BP-SeNPs significantly reduced Fusarium oxysporum infection rates, demonstrating potential for use in challenging outdoor environments. This thermosensitive gel coating provides an effective strategy for enhancing nanoselenium utilization on crop leaves through its temperature-responsive properties and strong postgelation adhesion.

Background:. Chronic venous leg ulcers (VLUs) are a common manifestation of chronic venous insufficiency, accounting for up to 70% of all chronic leg ulcers. Patients sustained refractory ulcers and persistent phleboedema even with a combination of different treatment methods. Lymphovenous bypass (LVB) has shown promising results in patients with lymphedema. We hypothesize that LVB could potentially alleviate VLUs and phleboedema, given their symptom similarities with lymphedema. Methods:. From May 2021 to June 2023, we prospectively deployed LVB in patients with nonhealing stasis ulcers after 4-week traditional care, or in those with persistent phleboedema despite prior surgery for vein etiologies. Demographics, healing course and recurrence, lymphoscintigraphy, and VLU quality of life (QoL) questionnaires were collected. Results:. Thirty-one patients were treated with LVB and additional skin grafting as necessary. Their mean age was 62.6 ± 14.7 years, with male predominance (20, 64.5%), and most patients sustained clinical, etiologic, anatomic, pathophysiologic classification C6 (25, 80.6%). Postoperatively, wound healing and phleboedema decongestion were observed mostly within 2 months. The VLU QoL questionnaire (39.3% response rate) showed improvement in QoL in activities, and psychological and symptom distress aspects. Conclusions:. Using LVB for chronic venous insufficiency showed an increase in the success rate of ulcer healing and decompression of the swollen limbs with durable results. Patient-reported outcome measures disclosed the potential benefits of LVB. Large-scale randomized controlled trials and pathophysiological studies are warranted to elucidate its efficacy.

Abstract Speaking constitutes one of the main goals of learning a second language (L2). Despite the increasing attention on the role of planning and language transfer in L2 learning, the combined effect of using different languages and pre-task planning on language production remains unclear. This study investigated whether the use of different languages in planning affects speaking performance and whether the effect differs by language proficiency. A total of 84 students in Chinese universities learning English as a foreign language participated in several speaking tasks after planning using their first language (L1) Chinese or L2 English. Findings showed that using L1 in planning results in significantly higher syntactic complexity, accuracy, and fluency in speaking performance than using L2 in planning, while the difference in lexical diversity were not statistically significant. Further analysis shows that for speech accuracy, the facilitative effect of L1 was stronger among low-proficient than high-proficient learners. Findings from this study support the use of L2 learners’ entire linguistic repertoire in speaking activities and provides implications on speech production theories as well as translanguaging pedagogies.

The deposition of nitrogen in soil may be influenced by the presence of different nitrogen components, which may affect the accessibility of soil nitrogen and invasive plant–soil microbe interactions. This, in turn, may alter the success of invasive plants. This study aimed to clarify the influences of the invasive plant Bidens pilosa L. on the physicochemical properties, carbon and nitrogen contents, enzymatic activities, and bacterial communities in soil in comparison to the native plant Pterocypsela laciniata (Houtt.) Shih treated with simulated nitrogen deposition at 5 g nitrogen m−2 yr−1 in four forms (nitrate, ammonium, urea, and mixed nitrogen). Monocultural B. pilosa resulted in a notable increase in soil pH but a substantial decrease in the moisture, electrical conductivity, ammonium content, and the activities of polyphenol oxidase, β-xylosidase, FDA hydrolase, and sucrase in soil in comparison to the control. Co-cultivating B. pilosa and P. laciniata resulted in a notable increase in total soil organic carbon content in comparison to the control. Monocultural B. pilosa resulted in a notable decrease in soil bacterial alpha diversity in comparison to monocultural P. laciniata. Soil FDA hydrolase activity and soil bacterial alpha diversity, especially the indices of Shannon’s diversity, Simpson’s dominance, and Pielou’s evenness, exhibited a notable decline under co-cultivated B. pilosa and P. laciniata treated with nitrate in comparison to those treated with ammonium, urea, and mixed nitrogen.

Drought may facilitate the invasion process of invasive plants, mainly because invasive plants can obtain a stronger growth competitiveness than native plants under drought. It is therefore imperative to illuminate the mechanisms underlying the successful invasion of invasive plants under drought, with a particular focus on the differences in the resistance of invasive and native plants to drought. This study aimed to elucidate the differences in the resistance between the invasive plant Amaranthus spinosus L. and the native plant A. tricolor L. to drought under a gradient of drought. The resistance of co-cultivated A. spinosus to drought was significantly higher than that of co-cultivated A. tricolor under light drought. Hence, A. spinosus may obtain a stronger competitive advantage than A. spinosus under co-cultivation conditions when treated with light drought. The resistance of the two plants to drought may be predominantly influenced by their height and biomass. This present study also defines a method for evaluating the stress resistance of a given plant species to stress by calculating the stress resistance index. This present study offers a robust theoretical foundation for determining the stress resistance of a given plant species and the environmental management of A. spinosus under drought.

We report the case of a 51-year-old woman who was initially hospitalized in the respiratory department with cough and fever. Urinary computed tomography (CT) showed two different incidental masses in the right kidney. The patient underwent a radical right nephrectomy without lymph node dissection and postoperative adjuvant treatment. The pathological examination of the surgical specimens showed a collision tumor composed of a clear cell renal cell carcinoma (CCRCC) and a clear cell papillary renal cell tumor (CCPRCT). To the best of our knowledge, this is the first such case reported to date. No recurrence of local or distant metastasis was found during routine follow-up 14 months after the operation.

This paper proposes three-phase 120° phase belt toroidal windings (120°-TW) and are applied in a double-sided permanent magnet linear synchronous motor (DSPMLSM), in which the incoming ends of all coils are on the same side and have the same incoming direction. First, the structure of the proposed motor is introduced and its operation principle is analyzed by describing the variation in the armature magnet field versus time. Second, based on the similar volume, magnetic load and electrical load, the initial parameters of the DSPMLSM with different winding arrangements are presented. Then, the finite-element models (FEMs) of the DSPMLSM with 120°-TW (120°-TWDSPMLSM) and traditional toroidal windings (TTW) are established to analyze the distribution of magnetic field, back electromotive force (back-EMF), detent force, thrust, efficiency and so on. Besides, the primary optimization of the detent force is designed. Finally, the results show that the thrust density and efficiency of the 120°-TWDSPMLSM is higher than that of DSPMLSM with TTW (TTWDSPMLSM). [ABSTRACT FROM AUTHOR]

One of the key reasons for the success of invasive plants is the functional differences between invasive plants and native plants. However, atmospheric nitrogen deposition may disrupt the level of available nitrogen in soil and the functional differences between invasive plants and native plants, which may alter the colonization of invasive plants. Thus, there is a pressing necessity to examine the effects of atmospheric nitrogen deposition containing different nitrogen components on the functional differences between invasive plants and native plants. However, the progress made thus far in this field is not sufficiently detailed. This study aimed to elucidate the effects of artificially simulated nitrogen deposition containing different nitrogen components (i.e., nitrate, ammonium, urea, and mixed nitrogen) on the functional differences between the Asteraceae invasive plant Bidens pilosa L. and the Asteraceae native plant Pterocypsela laciniata (Houtt.) Shih. The study was conducted over a four-month period using a pot-competitive co-culture experiment. The growth performance of P. laciniata, in particular with regard to the sunlight capture capacity (55.12% lower), plant supporting capacity (45.92% lower), leaf photosynthetic area (51.24% lower), and plant growth competitiveness (79.92% lower), may be significantly inhibited under co-cultivation condition in comparison to monoculture condition. Bidens pilosa exhibited a more pronounced competitive advantage over P. laciniata, particularly in terms of the sunlight capture capacity (129.43% higher), leaf photosynthetic capacity (40.06% higher), and enzymatic defense capacity under stress to oxidative stress (956.44% higher). The application of artificially simulated nitrogen deposition was found to facilitate the growth performance of monocultural P. laciniata, particularly in terms of the sunlight capture capacity and leaf photosynthetic area. Bidens pilosa exhibited a more pronounced competitive advantage (the average value of the relative dominance index of B. pilosa is ≈ 0.8995) than P. laciniata under artificially simulated nitrogen deposition containing different nitrogen components, especially when treated with ammonium (the relative dominance index of B. pilosa is ≈ 0.9363) and mixed nitrogen (the relative dominance index of B. pilosa is ≈ 0.9328). Consequently, atmospheric nitrogen deposition, especially the increased relative proportion of ammonium in atmospheric nitrogen deposition, may facilitate the colonization of B. pilosa via a stronger competitive advantage.

Bone regeneration materials (BRMs) bring us new sights into the clinical management bone defects. With advances in BRMs technologies, new strategies are emerging to promote bone regeneration. The aim of this study was to comprehensively assess the existing research and recent progress on BRMs, thus providing useful insights into contemporary research, as well as to explore potential future directions within the scope of bone regeneration therapy. A comprehensive literature review using formal data mining procedures was performed to explore the global trends of selected areas of research for the past 20 years. The study applied bibliometric methods and knowledge visualization techniques to identify and investigate publications based on the publication year (between 2002 and 2021), document type, language, country, institution, author, journal, keywords, and citation number. The most productive countries were China, United States, and Italy. The most prolific journal in the BRM field was Acta Biomaterialia, closely followed by Biomaterials. Moreover, recent investigations have been focused on extracellular matrices (ECMs) (370 publications), hydrogel materials (286 publications), and drug delivery systems (220 publications). Research hotspots related to BRMs and extracellular matrices from 2002 to 2011 were growth factor, bone morphogenetic protein (BMP)-2, and mesenchymal stem cell (MSC), whereas after 2012 were composite scaffolds. Between 2002 and 2011, studies related to BRMs and hydrogels were focused on BMP-2, in vivo, and in vitro investigations, whereas it turned to the exploration of MSCs, mechanical properties, and osteogenic differentiation after 2012. Research hotspots related to BRM and drug delivery were fibroblast growth factor, mesoporous materials, and controlled release during 2002–2011, and electrospinning, antibacterial activity, and in vitro bioactivity after 2012. Overall, composite scaffolds, 3D printing technology, and antibacterial activity were found to have an important intersection within BRM investigations, representing relevant research fields for the future. Taken together, this extensive analysis highlights the existing literature and findings that advance scientific insights into bone tissue engineering and its subsequent applications.

China's social work education dates back to the 1920s, but the profession disappeared for 36 years after the establishment of the People's Republic of China. Not until the late 1980s was social work education in China revived. At the turn of the new century, the Central Committee of the Chinese Communist Party and the State Council supported the urgent need for social work professionals to solve serious social problems to build what the government called a harmonious society. Since then, China's social work education has gone through rapid development. We examine the characteristics of China's social work education development since the economic reform of 1978 and present the challenges, opportunities, and future prospects for the profession. [ABSTRACT FROM AUTHOR]