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The breaking of spin symmetry in the single-particle resonances in deformed nuclei

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Nuclear Science and Techniques 2024年第3期35卷 237-245页

作者： Zhen-Yu Zheng shou-Wan chen Quan Liu School of Physics and Optoelectronic Engineering Anhui UniversityHefei 230601China

The exploration of spin symmetry (SS) in nuclear physics has been instrumental in identifying atomic nucleus structures.In this study,we solve the Dirac equation from the relativistic mean field (RMF) in complex momentum representation.We investigated SS and its breaking in single-particle resonant states within deformed nuclei,with a focus on the illustrative nucleus168Er.This was the initial discovery of a resonant spin doublet in a deformed nucleus,with the expectation of the SS approaching the continuum threshold.With increasing single-particle energy,the splitting of the resonant spin doublets widened significantly.This escalating splitting implies diminishing adherence to the SS,indicating a departure from the expected behavior as the energy levels increase.We also analyzed the width of the resonant states,showing that lower orbital angular momentum resonances possess shorter decay times and that SS is preserved within broad resonant doublets,as opposed to narrow resonant doublets.Comparing the radial density of the upper components for the bound-state and resonant-state doublets,it becomes evident that while SS is well-preserved in the bound states,it deteriorates in the resonant states.The impact of nuclear deformation (β_(2)) on SS was examined,demonstrating that an increase in β_(2) resulted in higher energy and width splitting in the resonant spin doublets,which is attributed to increased component mixing.Furthermore,the sensitivity of spin doublets to various potential parameters such as surface diffuseness (a),radius (R),and depth (Σ0) is discussed,emphasizing the role of these parameters in SS.This study provides valuable insights into the behavior of spin doublets in deformed nuclei and their interplay with the nuclear structure,thereby advancing our understanding of SS in the resonance state.

关键词： Spin symmetry Resonant states Deformed nuclei Complex-momentum representation

Emergent symmetry in quantum phase transition:From deconfined quantum critical point to gapless quantum spin liquid

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Science Bulletin 2024年第2期69卷 190-196页

作者： Wen-Yuan Liu shou-Shu Gong Wei-Qiang chen Zheng-cheng Gu Department of Physics The Chinese University of Hong KongHong KongChina Division of Chemistry and Chemical Engineering California Institute of TechnologyPasadena CA 91125USA School of Physical Sciences Great Bay UniversityDongguan 523000China Great Bay Institute for Advanced Study Dongguan 523000China Department of Physics and Shenzhen Institute for Quantum Science and Engineering Southern University of Science and TechnologyShenzhen 518055China Shenzhen Key Laboratory of Advanced Quantum Functional Materials and Devices Southern University of Science and TechnologyShenzhen 518055China

The emergence of exotic quantum phenomena in frustrated magnets is rapidly driving the development of quantum many-body physics,raising fundamental questions on the nature of quantum phase transitions.Here we unveil the behaviour of emergent symmetry involving two extraordinarily representative phenomena,i.e.,the deconfined quantum critical point(DQCP)and the quantum spin liquid(QSL)state.Via large-scale tensor network simulations,we study a spatially anisotropic spin-1/2 square-lattice frustrated antiferromagnetic(AFM)model,namely the J1x-J1y-J2 model,which contains anisotropic nearestneighbor couplings J1x,J1y and the next nearest neighbor coupling J2.For small J1y/J1x,by tuning J2,a direct continuous transition between the AFM and valence bond solid phase is observed.With growing J1y/J1x,a gapless QSL phase gradually emerges between the AFM and VBS phases.We observe an emergent O(4)symmetry along the AFM–VBS transition line,which is consistent with the prediction of DQCP theory.Most surprisingly,we find that such an emergent O(4)symmetry holds for the whole QSL–VBS transition line as well.These findings reveal the intrinsic relationship between the QSL and DQCP from categorical symmetry point of view,and strongly constrain the quantum field theory description of the QSL phase.The phase diagram and critical exponents presented in this paper are of direct relevance to future experiments on frustrated magnets and cold atom systems.

关键词： Tensor network Quantum phase transition Emergent symmetry Quantum spin liquid Deconfined quantum critical point Anisotropic

Personal Thermal Management by Radiative Cooling and Heating

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Nano-Micro Letters 2024年第8期16卷 225-267页

作者： Shidong Xue Guanghan Huang Qing chen Xungai Wang Jintu Fan Dahua shou School of Fashion and Textiles The Hong Kong Polytechnic UniversityHung HomKowloonHong Kong 999077People’s Republic of China Future Intelligent Wear Centre The Hong Kong Polytechnic UniversityHung HomKowloonHong Kong 999077People’s Republic of China State Key Laboratory of Precision Electronic Manufacturing Technology and Equipment Guangdong University of TechnologyGuangzhou 510006People’s Republic of China Shanghai International Fashion Innovation Center Donghua UniversityShanghai 200051People’s Republic of China Research Centre of Textiles for Future Fashion The Hong Kong Polytechnic UniversityHung HomKowloonHong Kong 999077People’s Republic of China Research Institute for Smart Energy The Hong Kong Polytechnic UniversityHung HomKowloonHong Kong 999077People’s Republic of China

Maintaining thermal comfort within the human body is crucial for optimal health and overall well-being.By merely broadening the setpoint of indoor temperatures,we could significantly slash energy usage in building heating,ventilation,and air-conditioning systems.In recent years,there has been a surge in advancements in personal thermal management(PTM),aiming to regulate heat and moisture transfer within our immediate surroundings,clothing,and skin.The advent of PTM is driven by the rapid development in nano/micro-materials and energy science and engineering.An emerging research area in PTM is personal radiative thermal management(PRTM),which demonstrates immense potential with its high radiative heat transfer efficiency and ease of regulation.However,it is less taken into account in traditional textiles,and there currently lies a gap in our knowledge and understanding of PRTM.In this review,we aim to present a thorough analysis of advanced textile materials and technologies for PRTM.Specifically,we will introduce and discuss the underlying radiation heat transfer mechanisms,fabrication methods of textiles,and various indoor/outdoor applications in light of their different regulation functionalities,including radiative cooling,radiative heating,and dual-mode thermoregulation.Furthermore,we will shine a light on the current hurdles,propose potential strategies,and delve into future technology trends for PRTM with an emphasis on functionalities and applications.

关键词： Personal thermal management Radiative cooling and heating Thermal comfort Dynamic thermoregulation

Spin effect on redox acceleration and regioselectivity in Fe-catalyzed alkyne hydrosilylation

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National Science Review 2024年第2期11卷 155-167页

作者： Peng He Meng-Yang Hu Jin-Hong Li Tian-Zhang Qiao yi-Lin Lu shou-Fei Zhu Frontiers Science Center for New Organic Matter State Key Laboratory and Institute of Elemento-Organic Chemistry Nankai University

Iron catalysts are ideal transition metal catalysts because of the Earths abundant, cheap, biocompatible features of iron salts. Iron catalysts often have unique open-shell structures that easily undergo spin crossover in chemical transformations, a feature rarely found in noble metal catalysts. Unfortunately, little is known currently about how the open-shell structure and spin crossover affect the reactivity and selectivity of iron catalysts, which makes the development of iron catalysts a low efficient trial-and-error program. In this paper, a combination of experiments and theoretical calculations revealed that the iron-catalyzed hydrosilylation of alkynes is typical spin-crossover catalysis. Deep insight into the electronic structures of a set of well-defined open-shell active formal Fe(0) catalysts revealed that the spin-delocalization between the iron center and the 1,10-phenanthroline ligand effectively regulates the iron center's spin and oxidation state to meet the opposite electrostatic requirements of oxidative addition and reductive elimination, respectively,and the spin crossover is essential for this electron transfer process. The triplet transition state was essential for achieving high regioselectivity through tuning the nonbonding interactions. These findings provide an important reference for understanding the effect of catalyst spin state on reaction. It is inspiring for the development of iron catalysts and other Earth-abundant metal catalysts, especially from the point of view of ligand development.

关键词： spin effect spin-delocalization spin crossover iron-catalysis alkyne hydrosilylation

Evaluation of water management on arsenic methylation and volatilization in arsenic-contaminated soils strengthened by bioaugmentation and biostimulation

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Journal of Environmental Sciences 2024年第3期137卷 515-526页

作者： Peng chen yi Liu Guo-Xin Sun State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Key Laboratory of Aquatic Botany and Watershed Ecology Wuhan Botanical GardenChinese Academy of SciencesWuhan 430074China University of Chinese Academy of Sciences Beijing 100049China

Arsenic(As) fate in paddy fields has been one of the most significant current issues due to the strong As accumulation potential of rice plants under fooded conditions. However,no attempt was done to explore As methylation and volatilization under non-fooded conditions. Herein, we investigated the effects of water management on As methylation and volatilization in three arsenic-contaminated soils enhanced by biostimulation with strawderived organic matter and bioaugmentation with genetic engineered Pseudomonas putida KT2440(GE P. putida). Under fooded conditions, the application of biochar(BC), rice straw(RS)and their combination(BC+RS) increased total As in porewater. However, these effects were greatly attenuated under non-fooded conditions. Compared with RS amendment alone, the combination of GE P. putida and RS further promoted the As methylation and volatilization,and the promotion percentage under non-fooded conditions were significantly higher than that under fooded conditions. The combined GE P. putida and RS showed the highest efficiency in As methylation(88 μg/L) and volatilization(415.4 μg/(kg·year)) in the non-fooded soil with moderate As contamination. Finally, stepwise multiple linear regression analysis presented that methylated As, DOC and p H in porewater were the most important factors contributing to As volatilization. Overall, our findings suggest that combination of bioaugmentation with GE P. putida and biostimulation with RS/BC+RS is a potential strategy for bioremediation of arsenic-contaminated soils by enhancing As methylation and volatilization under non-fooded conditions.

关键词： Arsenic methylation Arsenic volatilization Water management Straw incorporation Bioaugmentation

Unique method for removal of knotted lumbar epidural catheter: A case report

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World Journal of Clinical Cases 2024年第10期12卷 1824-1829页

作者： Nian-Hua Deng Xiao-Cong chen shou-Bo Quan Anesthesia and Surgery Center Dongguan Songshan Lake Central HospitalDongguan 523326Guangdong ProvinceChina

BACKGROUND Combined spinal-epidural(CSE)anesthesia is the preferred anesthesia method for cesarean delivery.The use of an epidural catheter is essential for administering additional drugs intraoperatively and managing postoperative pain.However,the insertion of epidural catheters is associated with various complications,such as total spinal anesthesia,symptoms indicative of spinal nerve root irritation,and challenges in epidural catheter removal.CASE SUMMARY We present a case report of a challenging epidural catheter removal due to knotting.The lumbar computed tomography scan results revealed that the catheter formed a tight knot in the epidural space.We used a novel extubation method and successfully removed the catheter.CONCLUSION The operator can use opposite forces to"spiral"apart the spinal joints by positioning the patient's body in a specific position.The findings indicate that,when combined with imaging examination results,this method is effective for the removal of epidural catheters.

关键词： Epidural catheter Knotting Challenging extubation Case report

Molecular evolution of Toll-like receptors in rodents

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Integrative Zoology 2024年第3期19卷 371-386页

作者： Qianqian SU yi chen Hongxuan HE College of Forestry Central South University of Forestry and TechnologyChangshaChina National Research Center for Wildlife-Borne Diseases Institute of ZoologyChinese Academy of SciencesBeijingChina

Toll-like receptors(TLRs),the key sensor molecules in vertebrates,trigger the innate immunity and prime the adaptive immune system.The TLR family of rodents,the largest order of mammals,typically contains 13 TLR genes.However,a clear picture of the evolution of the rodent TLR family has not yet emerged and the TLR evolutionary patterns are unclear in rodent clades.Here,we analyzed the natural variation and the evolutionary processes acting on the TLR family in rodents at both the interspecific and population levels.Our results showed that rodent TLRs were dominated by purifying selection,but a series of positively selected sites(PSSs)primarily located in the ligand-binding domain was also identified.The numbers of PSSs differed among TLRs,and nonviralsensing TLRs had more PSSs than those in viral-sensing TLRs.Gene-conversion events were found between TLR1 and TLR6 in most rodent species.Population genetic analyses showed that TLR2,TLR8,and TLR12 were under positive selection in Rattus norvegicus and R.tanezumi,whereas positive selection also acted on TLR5 and TLR9 in the former species,as well as TLR1 and TLR7 in the latter species.Moreover,we found that the proportion of polymorphisms with potentially functional change was much lower in viral-sensing TLRs than in nonviral-sensing TLRs in both of these rat species.Our findings revealed the first thorough insight into the evolution of the rodent TLR genetic variability and provided important novel insights into the evolutionary history of TLRs over long and short timescales.

关键词： adaptive evolution gene conversion positive selection rodents Toll-like receptors

Regulation of seed traits in soybean

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aBIOTECH 2023年第4期4卷 372-385页

作者： Yang Hu Yue Liu Jun-Jie Wei Wan-Ke Zhang shou-yi chen Jin-Song Zhang State Key Lab of Plant Genomics Institute of Genetics and Developmental BiologyInnovative Academy of Seed DesignChinese Academy of SciencesBeijing 100101China College of Advanced Agricultural Sciences University of Chinese Academy of SciencesBeijing 100049China

Soybean (Glycine max) is an essential economic crop that provides vegetative oil and protein forhumans, worldwide. Increasing soybean yield as well as improving seed quality is of great importance.Seed weight/size, oil and protein content are the three major traits determining seed quality, and seedweight also influences soybean yield. In recent years, the availability of soybean omics data and thedevelopment of related techniques have paved the way for better research on soybean functionalgenomics, providing a comprehensive understanding of gene functions. This review summarizes theregulatory genes that influence seed size/weight, oil content and protein content in soybean. We alsoprovided a general overview of the pleiotropic effect for the genes in controlling seed traits andenvironmental stresses. Ultimately, it is expected that this review will be beneficial in breedingimproved traits in soybean.

关键词： Soybean Seed weight and size Oil Protein

Development and validation of a nomogram to predict allograft survival after pediatric liver transplantation

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World Journal of Pediatrics 2024年第3期20卷 239-249页

作者： Guang-Xiang Gu Shu-Ting Pan yi-chen Fan chen chen Qiang Xia Department of Liver Surgery Renji HospitalShanghai Jiaotong University School of MedicineNo.160 Pujian RoadPudong New DistrictShanghai 200128China Department of Liver Transplantation Sun Yet-Sen Memorial HospitalSun Yat-Sen UniversityNo.107 Yanjiang West RoadGuangzhou 510080China Clinical Center for Investigation Renji HospitalShanghai Jiaotong University School of MedicineShanghaiChina Department of Anesthesiology Renji HospitalShanghai Jiaotong University School of MedicineShanghaiChina

Background Liver transplantation is the main treatment for cholestatic liver disease and some metabolic liver diseases in children.However,no accurate prediction model to determine the survival probability of grafts prior to surgery exists.This study aimed to develop an effective prognostic model for allograft survival after pediatric liver transplantation.Methods This retrospective cohort study included 2032 patients who underwent pediatric liver transplantation between January 1,2006,and January 1,2020.A nomogram was developed using Cox regression and validated based on bootstrap sampling.Predictive and discriminatory accuracies were determined using the concordance index and visualized using calibration curves;net benefits were calculated for model comparison.An online Shiny application was developed for easy access to the model.Results Multivariable analysis demonstrated that preoperative diagnosis,recipient age,body weight,graft type,preoperative total bilirubin,interleukin-1β,portal venous blood flow direction,spleen thickness,and the presence of heart disease and cholangitis were independent factors for survival,all of which were selected in the nomogram.Calibration of the nomogram indicated that the 1-,3-,and 5-year predicted survival rates agreed with the actual survival rate.The concordance indices for graft survival at 1,3,and 5 years were 0.776,0.757,and 0.753,respectively,which were significantly higher than those of the Pediatric End-Stage Liver Disease and Child-Pugh scoring systems.The allograft dysfunction risk of a recipient could be easily predicted using the following URL:https://aspelt.***.io/ASPELT/l Conclusion The allograft survival after pediatric liver transplantation(ASPELT)score model can effectively predict the graft survival rate after liver transplantation in children,providing a simple and convenient evaluation method for clinicians and patients.

关键词： Allograft survival Nomogram Pediatric liver transplantation