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Preparation of Chemically Recyclable Poly(ether-alt-ester) by the Ring Opening Polymerization of Cyclic Monomers Synthesized by Coupling Glycolide and Epoxides

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Chinese Journal of Polymer Science 2024年第2期42卷 168-175,I0006页

作者： Feng Ren Zhuang-Zhuang Liang ming-xin niu Chen-Yang Hu Xuan Pang Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei230026China

Polyester and polyether are two key oxygenated polymers, and completely alternative sequence of poly(ester-alt-ether) could efficiently combine the advantages(including flexibility, degradability, etc.) of both segments. Currently, despite their copolymers could be synthesized from one-pot mixture of cyclic esters and epoxides, perfectly alternative microstructure is very challenging to realize and typically restricted to certain monomer pairs. Moving forward, synthesizing poly(ester-alt-ether) from commercially available and largescale monomers would be a significant advance. For example, successfully commercialized poly(glycolic acid)(PGA), which is not easily soluble in polymers due to its high crystallinity and is brittle and difficult to control the degradation cycle, would encounter a new paradigm if engineered into poly(ester-altether). In this work, starting from the design of monomer with hybrid structures, we successfully synthesized a series of 1,4-dioxan-2-one containing different substituents based on glycolide(GA) and epoxides using commercially available Salen-Cr(III) and PPNCl catalytic *** new monomers underwent ring-opening polymerization(ROP) to form a series of poly(ester-alt-ether) with perfectly alternating glycolic acid and propylene glycol repeat units under catalytic system of thiourea/base. The poly(ester-alt-ether) have significantly lower glass-transition temperature than PGA. Additionally, the poly(ester-alt-ether) can be chemically recovered to monomer using Sn(Oct)2 or 1,8-diazabicyclo[5.4.0]undecane-7-ene(DBU) as a catalyst in solution, thus establishing a closed-loop life cycle. From monomers derived from GA and epoxides, this work furnishes a novel strategy for the synthesis of poly(ester-alt-ether) with chemical recyclability.

关键词： Polyester Polyether Alternative copolymer Ring-opening polymerization

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一个公平的反拒认协议

通信学报 2002年第2期23卷 51-57页

作者：邓所云胡正名钮心忻杨义先北京邮电大学信息安全中心北京100876

反拒认是实现电子商务的一个重要前提条件,公平也是人们在交易过程中所追求的重要目标。本文基于此目标提出了一个公平的反拒认协议,解决了收发双方可能发生的拒认问题,并使收发双方处于平等的位置上。本协议由可靠的第三方产生反拒认证... 详细信息

反拒认是实现电子商务的一个重要前提条件,公平也是人们在交易过程中所追求的重要目标。本文基于此目标提出了一个公平的反拒认协议,解决了收发双方可能发生的拒认问题,并使收发双方处于平等的位置上。本协议由可靠的第三方产生反拒认证据,数据交互次数少,高效实用。

关键词：反拒认协议通信协议电子商务

Burden of mental disorders and risk factors in the Western Pacific region from 1990 to 2021

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World Journal of Psychiatry 2025年第1期15卷 93-105页

作者： Ya-xin Xu Xiao-Xuan niu Wen-Chang Jia Jing Wen Xue-Lin Cheng Yan Han ming-Hui Peng Jing Zhou Yao Liu Sun-Fang Jiang Xiao-Pan Li Department of Health Management Centre Zhongshan HospitalFudan UniversityShanghai 200030China Department of General Practice Zhongshan HospitalFudan UniversityShanghai 200030China Department of Nutrition Zhongshan HospitalFudan UniversityShanghai 200032China School of Public Health Fudan UniversityShanghai 200032China

BACKGROUND The burden of mental disorders(MD)in the Western Pacific Region(WPR)re-mains a critical public health concern,with substantial variations across demogra-phics and *** To analyze the burden of MD in the WPR from 1990 to 2021,along with associated risk factors,to reveal changing trends and emerging *** We used data from the Global Burden of Disease 2021,analyzing prevalence,incidence,and disability-adjusted life years(DALYs)of MD from 1990 to *** methods included age-standardisation and uncertainty analysis to address variations in population structure and data *** Between 1990 and 2021,the prevalence of MD rose from 174.40 million cases[95%uncertainty interval(UI):160.17-189.84]to 234.90 million cases(95%UI:219.04-252.50),with corresponding DALYs increasing from 22.8 million(95%UI:17.22-28.79)to 32.07 million(95%UI:24.50-40.68).During this period,the burden of MD shifted towards older age *** and anxiety disorders were predominant,with females showing higher DALYs for depressive and anxiety disorders,and males more affected by conduct disorders,attention-deficit hyperactivity disorder,and autism spectrum ***,New Zealand,and Malaysia reported the highest burdens,whereas Vietnam,China,and Brunei Darussalam reported the ***,childhood sexual abuse and bullying,and intimate partner violence emerged as significant risk *** This study highlights the significant burden of MD in the WPR,with variations by age,gender,and *** coronavirus disease 2019 pandemic has exacerbated the situation,emphasizing the need for a coordinated response.

关键词： Mental disorders Western pacific region Global Burden of Disease Risk factors Disability-adjusted life years

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不同施肥方式对伊贝母生长及土壤养分的影响

新疆农业科学 2017年第2期54卷 281-288页

作者：马红红陈宝燕杨涛程争鸣牛新湘马兴旺新疆农业科学院土壤肥料与农业节水研究所乌鲁木齐830091 乌鲁木齐市米东区农产品质量安全检测中心乌鲁木齐830011 中国科学院新疆生态与地理研究所乌鲁木齐830000

【目的】研究新疆伊犁地区伊贝母的最佳施肥技术模式。【方法】通过采用四因素三水平正交试验设计,设计微生物菌肥、磷肥,生物有机肥+有机物料腐熟剂,精制有机肥+有机物料腐熟剂4因素,在优化施肥(2水平)基础上,设计1水平(2水平×0.5)、... 详细信息

【目的】研究新疆伊犁地区伊贝母的最佳施肥技术模式。【方法】通过采用四因素三水平正交试验设计,设计微生物菌肥、磷肥,生物有机肥+有机物料腐熟剂,精制有机肥+有机物料腐熟剂4因素,在优化施肥(2水平)基础上,设计1水平(2水平×0.5)、3水平(2水平×1.5),正交处理共9个,对伊贝母生长及土壤进行了测定。【结果】不同施肥量处理下的伊贝母植株高度、伊贝母植株鲜重、鳞茎鲜重、土壤有机质、土壤全氮含量和土壤p H值均不同;随着伊贝母生育进程的推进,各个处理下的土壤p H均表现为萌芽期显著高于现蕾期和始花期,而土壤有机质和土壤全氮含量规律并不明显;不同施肥量处理下,伊贝母每667 m^2株数没有明显差异;在同一微生物菌肥施用量下,伊贝母产量的变化趋势无明显规律,处理8即微生物菌肥为6 kg/667m^2,磷肥为18 kg/667 m^2,生物有机肥+有机物料腐剂为16 kg/667 m^2,精制有机肥+有机物料腐剂为60 kg/667 m^2时,伊贝母产量最高为381.14 kg/667 m^2;在单一微生物菌肥施用量下,伊贝母产量的变化趋势无明显规律。【结论】以微生物菌肥、磷肥基施为主,配施生物有机肥、有机物料腐熟剂,生育期开沟追施微生物菌肥,可获得伊贝母高产。

关键词：伊贝母不同施肥方式生长土壤养分

Clinical effects of phospholipase D2 in attenuating acute pancreatitis

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World Journal of Gastroenterology 2025年第2期31卷 52-60页

作者： Jin-Wei niu Guo-Chao Zhang Wu Ning Hai-Bin Liu Hua Yang Chao-Feng Li Department of General Surgery China-Japan Friendship HospitalBeijing 100029China

BACKGROUND The objective of the current study was to elucidate the clinical mechanism through which phospholipase D2(PLD2)exerted a regulatory effect on neutrophil migra-tion,thereby alleviating the progression of acute *** To elucidate the clinical mechanism through which PLD2 exerted a regulatory effect on neutrophil migration,thereby alleviating the progression of acute *** The study involved 90 patients diagnosed with acute pancreatitis,admitted to our hospital between March 2020 and November 2022.A retrospective analysis was conducted,categorizing patients based on Ranson score severity into mild(n=25),moderate(n=30),and severe(n=35)*** data was collected for each *** blot analysis assessed PLD2 protein expression in patient ***-time reverse transcription polymerase chain reaction was used to evaluate the mRNA expression of chemokine receptors associated with neutrophil *** levels of inflammatory factors in patients were detected using enzyme-linked immunosorbent *** migration tests were conducted to compare migration of neutrophils across groups and analyze the influence of PLD2 on neutrophil *** Overall data analysis did not find significant differences between patient groups(P>0.05).The expression of PLD2 protein in the severe group was lower than that in the moderate and mild groups(P<0.05).The expression level of PLD2 in the moderate group was also lower than that in the mild group(P<0.05).The severity of acute pancreatitis is negatively correlated with PLD2 expression(r=-0.75,P=0.002).The mRNA levels of C-X-C chemokine receptor type 1,C-X-C chemokine receptor type 2,C-C chemokine receptor type 2,and C-C chemokine receptor type 5 in the severe group are significantly higher than those in the moderate and mild groups(P<0.05),and the expression levels in the moderate group are also higher than those in the mild group(P<0.05).The levels of C-reactive protein,tumo

关键词： Phospholipase D2 Neutrophil migration Acute pancreatitis Retrospective analysis Inflammatory response

Bidirectional regulation of the brain-gut-microbiota axis following traumatic brain injury

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Neural Regeneration Research 2025年第8期20卷 2153-2168页

作者： xinyu You Lin niu Jiafeng Fu Shining Ge Jiangwei Shi Yanjun Zhang Pengwei Zhuang National Key Laboratory of Chinese Medicine Modernization Tianjin University of Traditional Chinese MedicineTianjinChina Haihe Laboratory of Modern Chinese Medicine Tianjin University of Traditional Chinese MedicineTianjinChina First Teaching Hospital of Tianjin University of Traditional Chinese Medicine TianjinChina National Clinical Research Center for Chinese Medicine Acupuncture and Moxibustion TianjinChina

Traumatic brain injury is a prevalent disorder of the central nervous *** addition to primary brain parenchymal damage,the enduring biological consequences of traumatic brain injury pose long-term risks for patients with traumatic brain injury;however,the underlying pathogenesis remains unclear,and effective intervention methods are *** dysfunction is a significant consequence of traumatic brain *** the most densely innervated peripheral tissue in the body,the gut possesses multiple pathways for the establishment of a bidirectional“brain-gut axis”with the central nervous *** gut harbors a vast microbial community,and alterations of the gut niche contribute to the progression of traumatic brain injury and its unfavorable prognosis through neuronal,hormonal,and immune pathways.A comprehensive understanding of microbiota-mediated peripheral neuroimmunomodulation mechanisms is needed to enhance treatment strategies for traumatic brain injury and its associated *** comprehensively reviewed alterations in the gut microecological environment following traumatic brain injury,with a specific focus on the complex biological processes of peripheral nerves,immunity,and microbes triggered by traumatic brain injury,encompassing autonomic dysfunction,neuroendocrine disturbances,peripheral immunosuppression,increased intestinal barrier permeability,compromised responses of sensory nerves to microorganisms,and potential effector nuclei in the central nervous system influenced by gut ***,we reviewed the mechanisms underlying secondary biological injury and the dynamic pathological responses that occur following injury to enhance our current understanding of how peripheral pathways impact the outcome of patients with traumatic brain *** review aimed to propose a conceptual model for future risk assessment of central nervous system-related diseases while elucidating novel insights into the bidirectional effec

关键词： traumatic brain injury brain-gut-microbiome axis gut microbiota neuroimmune immunosuppression host defense vagal afferents bacterial infection dorsal root ganglia nociception neural circuitry

C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 pathway as a therapeutic target and regulatory mechanism for spinal cord injury

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Neural Regeneration Research 2025年第8期20卷 2231-2244页

作者： Xiangzi Wang Xiaofei niu Yingkai Wang Yang Liu Cheng Yang Xuyi Chen Zhongquan Qi School of Medicine Guangxi UniversityNanningGuangxi Zhuang Autonomous RegionChina Graduate School of Tianjin University of Traditional Chinese Medicine TianjinChina Characteristic Medical Center of People’s Armed Police Forces TianjinChina Fujian Maternity and Child Health Hospital FuzhouFujian ProvinceChina

Spinal cord injury involves non-reversible damage to the central nervous system that is characterized by limited regenerative capacity and secondary inflammatory *** expression of the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis exhibits significant differences before and after *** studies have revealed that the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis is closely associated with secondary inflammatory responses and the recruitment of immune cells following spinal cord injury,suggesting that this axis is a novel target and regulatory control point for *** review comprehensively examines the therapeutic strategies targeting the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis,along with the regenerative and repair mechanisms linking the axis to spinal cord ***,we summarize the upstream and downstream inflammatory signaling pathways associated with spinal cord injury and the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 *** review primarily elaborates on therapeutic strategies that target the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis and the latest progress of research on antagonistic drugs,along with the approaches used to exploit new therapeutic targets within the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 axis and the development of targeted ***,there are presently no clinical studies relating to spinal cord injury that are focusing on the C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 *** review aims to provide new ideas and therapeutic strategies for the future treatment of spinal cord injury.

关键词： apoptosis C-C motif chemokine ligand 2/C-C motif chemokine receptor 2 pathway C-C motif chemokine receptor 2 antagonists chemokine ligand 2 chemokine receptor 2 inflammation macrophage microglia spinal cord injury therapeutic method

Liposomes as versatile agents for the management of traumatic and nontraumatic central nervous system disorders:drug stability,targeting efficiency,and safety

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Neural Regeneration Research 2025年第7期20卷 1883-1899页

作者： mingyu Zhang Chunyu Xiang Renrui niu Xiaodong He Wenqi Luo Wanguo Liu Rui Gu Department of Orthopedic Surgery China-Japan Union Hospital of Jilin UniversityChangchunJilin ProvinceChina

Various nanoparticle-based drug delivery systems for the treatment of neurological disorders have been widely ***,their inability to cross the blood–brain barrier hampers the clinical translation of these therapeutic *** are nanoparticles composed of lipid bilayers,which can effectively encapsulate drugs and improve drug delivery across the blood–brain barrier and into brain tissue through their targeting and ***,they can potentially treat traumatic and nontraumatic central nervous system *** this review,we outlined the common properties and preparation methods of liposomes,including thin-film hydration,reverse-phase evaporation,solvent injection techniques,detergent removal methods,and microfluidics ***,we comprehensively discussed the current applications of liposomes in central nervous system diseases,such as Alzheimer's disease,Parkinson's disease,Huntington's disease,amyotrophic lateral sclerosis,traumatic brain injury,spinal cord injury,and brain *** studies related to liposomes are still in the laboratory stage and have not yet entered clinical ***,their application as drug delivery systems in clinical practice faces challenges such as drug stability,targeting efficiency,and ***,we proposed development strategies related to liposomes to further promote their development in neurological disease research.

关键词： Alzheimer's disease amyotrophic lateral sclerosis brain tumors central nervous system Huntington's disease liposome drug delivery neurological disorders Parkinson's disease spinal cord injury traumatic brain injury

Ca-and Mg-rich waste as high active carrier for chemical looping gasification of biomass

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Chinese Journal of Chemical Engineering 2021年第10期34卷 145-154页

作者： xin niu Laihong Shen School of Energy and Power Engineering Nanjing University of Science and TechnologyNanjing 210094China Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education School of Energy and EnvironmentSoutheast UniversityNanjing 210096China

Chemical looping gasification(CLG)is a promising technology for high-quality syngas *** key issue to successful CLG is the selection of high-performance oxygen *** this study,several Ca-and Mg-rich steelmaking wastes from steel industry,such as blast furnace slag(BF slag),blast furnace dust(BF dust)and Linz-Donawitz converter slag(LD slag),were used as oxygen carriers in chemical looping gasification of *** results showed that the reducibility of Ca-and Mg-rich waste,especially LD slag and BF dust,was superior to that of *** long-term operation,the cyclic stability of steelmaking waste was *** dust showed a poor stability,while the other carrier(hematite,BF slag or LD slag)presented an excellent stability during multiple redox cycles in spite of partial sintering and ***,the effects of supply oxygen coefficient(O/B ratio)and reaction temperature on CLG of biomass were *** results revealed that Ca-and Mg-rich waste exhibited a higher syngas production compared to *** higher performance could be attributed to the improved reduction rate of Fe2O3 and gasification rate of biomass by Ca or Mg in steelmaking *** addition,LD slag exhibited the higher gas value at the O/B ratio of 1 at 900℃.As a consequence,LD slag was an appropriate oxygen carrier for CLG of biomass in terms of perfect reducibility,superior cyclic stability and high reactivity.

关键词： Biomass Syngas Gasification Ca-and Mg-rich waste Chemical looping