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Revisiting collagen:A breaching point in tumor immunotherapy
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作者 Yi-Da Wang Hai-Yue You +3 位作者 Feng zhang Xin Ning Jie Mei yan zhang 《Life Research》 2026年第1期1-4,共4页
Immunotherapy has brought unprecedented breakthroughs to advanced malignant tumors,yet the immune microenvironment shaped by the tumor stroma has often been underestimated in the traditional focus on the“immune check... Immunotherapy has brought unprecedented breakthroughs to advanced malignant tumors,yet the immune microenvironment shaped by the tumor stroma has often been underestimated in the traditional focus on the“immune checkpoint-T cell”axis.Collagen not only constitutes a mechanical barrier that distinguishes between the periphery and core of solid tumors but also systematically remodels the orientation of metabolism,vasculature,and immune cell phenotypic plasticity through its spatial density,fiber arrangement,and crosslinking patterns(F igure 1)[1,2].Abundant evidence suggests that over-accumulated types I and III collagen drive CD8+T cell exhaustion,NK cell functional inhibition,and tumor-associated macrophage polarization through ligand-receptor networks involving LAIR-1,DDR2,andβ1/β3 integrins[3-6].Mechanistically,collagen engagement of LAIR-1 delivers inhibitory signals in effector lymphocytes,promoting dysfunctional or exhausted states[7-9].In parallel,collagen-β1/β3 integrin signaling activates mechanotransduction pathways(e.g.,FAK/SRC),reducing T-cell motility and immune-tumor contact,while DDR2 activation supports matrix-remodeling programs that limit lymphocyte trafficking. 展开更多
关键词 immune microenvironment advanced malignant tumorsyet tumor immunotherapy immune cell phenotypic plasticity COLLAGEN tumor stroma collagen I solid tumors
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Diagnostic clues in patients with clinical malabsorption and pathological small intestinal villous atrophy:Immune-mediated type and beyond
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作者 Mu-Han Li Qi-Pu Wang +9 位作者 Cheng-Zhu Ou Tian-Ming Xu yang Chen Hao Tang yan zhang yan-Jun Lai Xu-Zhen Qin Ji Li Wei-Xun Zhou Jing-Nan Li 《World Journal of Gastroenterology》 2026年第2期37-58,共22页
Small intestinal villi are essential for nutrient absorption,and their impairment can lead to malabsorption.Small intestinal villous atrophy(VA)encompasses a heterogeneous group of disorders,including immune-mediated ... Small intestinal villi are essential for nutrient absorption,and their impairment can lead to malabsorption.Small intestinal villous atrophy(VA)encompasses a heterogeneous group of disorders,including immune-mediated conditions(e.g.,celiac disease,autoimmune enteropathy,inborn errors of immunity),lymphoproliferative disorders(e.g.,enteropathy-associated T-cell lymphoma),infectious causes(e.g.,tropical sprue,Whipple’s disease),iatrogenic factors(e.g.,Olmesartanassociated enteropathy,graft-vs-host disease),as well as inflammatory and idiopathic types.These disorders are often rare and challenging to distinguish due to overlapping clinical,serological,endoscopic,and histopathological features.Through a systematic literature search using keywords such as small intestinal VA,malabsorption,and specific enteropathies,this review provides a comprehensive overview of diagnostic clues for VA and malabsorption.We systematically summarize the pathological characteristics of each condition to assist pathologists and clinicians in accurately identifying the underlying etiologies.Current studies still have many limitations and lack broader and deeper investigations into these diseases.Therefore,future research should focus on the development of novel diagnostic tools,predictive models,therapeutic targets,and mechanistic molecular studies to refine both diagnosis and management strategies. 展开更多
关键词 Autoimmune enteropathy Celiac disease Diagnosis Inborn errors of immunity MALABSORPTION PATHOLOGY Small intestinal villous atrophy disorder
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Crystallographic Engineering Enables Fast Low‑Temperature Ion Transport of TiNb_(2)O_(7)for Cold‑Region Lithium‑Ion Batteries
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作者 Lihua Wei Shenglu Geng +7 位作者 Hailu Liu Liang Deng Yiyang Mao yanbin Ning Biqiong Wang Yueping Xiong yan zhang Shuaifeng Lou 《Nano-Micro Letters》 2026年第3期428-444,共17页
TiNb_(2)O_(7)represents an up-and-coming anode material for fast-charging lithium-ion batteries,but its practicalities are severely impeded by slow transfer rates of ionic and electronic especially at the low-temperat... TiNb_(2)O_(7)represents an up-and-coming anode material for fast-charging lithium-ion batteries,but its practicalities are severely impeded by slow transfer rates of ionic and electronic especially at the low-temperature conditions.Herein,we introduce crystallographic engineering to enhance structure stability and promote Li+diffusion kinetics of TiNb_(2)O_(7)(TNO).The density functional theory computation reveals that Ti^(4+)is replaced by Sb^(5+)and Nb^(5+)in crystal lattices,which can reduce the Li+diffusion impediment and improve electronic conductivity.Synchrotron radiation X-ray 3D nano-computed tomography and in situ X-ray diffraction measurement confirm the introduction of Sb/Nb alleviates volume expansion during lithiation and delithiation processes,contributing to enhancing structure stability.Extended X-ray absorption fine structure spectra results verify that crystallographic engineering also increases short Nb-O bond length in TNO-Sb/Nb.Accordingly,the TNO-Sb/Nb anode delivers an outstanding capacity retention rate of 89.8%at 10 C after 700 cycles and excellent rate performance(140.4 mAh g^(−1) at 20 C).Even at−30℃,TNO-Sb/Nb anode delivers a capacity of 102.6 mAh g^(−1) with little capacity degeneration for 500 cycles.This work provides guidance for the design of fast-charging batteries at low-temperature condition. 展开更多
关键词 Lithium-ion batteries Low-temperature conditions Crystallographic engineering TiNb_(2)O_(7) Structure stability
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Reducing bentonite usage in iron ore pelletization through synergistic modification with mechanical force and DMSO:Effects and mechanisms
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作者 Yinrui Dong Yongbin yang +4 位作者 Lin Wang Qianqian Duan Qian Li yan zhang Tao Jiang 《International Journal of Minerals,Metallurgy and Materials》 2026年第1期177-190,共14页
Bentonite is a necessary binder in producing pellets.Its excessive use reduces the iron grade of pellets and increases production costs.Minimizing bentonite dosage is essential for producing high-quality iron ore pell... Bentonite is a necessary binder in producing pellets.Its excessive use reduces the iron grade of pellets and increases production costs.Minimizing bentonite dosage is essential for producing high-quality iron ore pellets.Addressing the gap in the application of organically-intercalated modified bentonite in the pelletizing field,this study introduces an innovative modification process for bentonite that employs the synergistic effect of mechanical force and dimethyl sulfoxide to enhance the intercalation of organic compounds within bentonite,thus significantly enhancing its binding performance.The colloid value and swell capacity of modified bentonite(98.5 m L/3g and 55.0 m L/g)were much higher than the original bentonite(90.5 m L/3g and 17.5 m L/g).With the decrease of bentonite dosage from1.5wt%to 1.0wt%,the drop number of green pellets from a height of 0.5 m and the compressive strengths of roasted pellets using the modified bentonite(6.0 times and 2916 N per pellet)were significantly higher than those of the original bentonite(4.0 times and 2739 N per pellet).This study provides a comprehensive analysis of the intercalation modification mechanism of bentonite,offering crucial technical insights for the development of high-performance modified bentonite as iron ore pellet binders. 展开更多
关键词 PELLETS bentonite modification mechanical force dimethyl sulfoxide organic intercalation
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Mapping stripe rust resistance genes by BSR-Seq:YrMM58 and YrHY1 on chromosome 2AS in Chinese wheat lines Mengmai 58 and Huaiyang 1 are Yr17 被引量:6
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作者 Yong Wang Huaizhi zhang +15 位作者 Jingzhong Xie Bingmin Guo Yongxing Chen Huaiyu zhang Ping Lu Qiuhong Wu Miaomiao Li Deyun zhang Guanghao Guo Jian yang Panpan zhang yan zhang Xicheng Wang Hong Zhao Tingjie Cao Zhiyong Liu 《The Crop Journal》 SCIE CAS CSCD 2018年第1期91-98,共8页
Stripe rust(yellow rust), caused by Puccinia striiformis f. sp. tritici(PST),is one of the most devastating fungal diseases in common wheat(Triticum aestivum L.) in China and worldwide. Resistance breeding is the most... Stripe rust(yellow rust), caused by Puccinia striiformis f. sp. tritici(PST),is one of the most devastating fungal diseases in common wheat(Triticum aestivum L.) in China and worldwide. Resistance breeding is the most effective strategy to control diseases in crop plants. Chinese wheat lines Mengmai 58 and Huaiyang 1 are highly resistant to PST race CYR34(V26) at the adult plant stage. To genetically map the underlying resistance genes we developed segregating populations by crossing Mengmai 58 and Huaiyang 1 with the susceptible cultivar Nongda 399. The stripe rust resistances in Mengmai 58 and Huaiyang 1 were both controlled by single dominant genes, provisionally designated YrMM58 and YrHY1, respectively. Bulked segregant RNA-Seq(BSR-Seq) analysis showed that YrMM58 and YrHY1 were located in the same distal ~16 Mb region on chromosome 2 AS.Comparative genomics analysis with the physical map of Aegilops tauschii proved useful for developing additional markers to saturate the genetic linkage map. YrMM58 and YrHY1 were mapped to the distal end of chromosome arm 2 AS, with the closest marker WGGB148 being 7.7 cM and 3.8 cM from the resistance gene, which was considered to be Yr17. These markers can be used in marker-assisted selection. 展开更多
关键词 Genetic MAPPING STRIPE rust TRITICUM AESTIVUM BSR-seq SNP
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Synthesis and insecticidal evaluation of novel sulfide-containing amide derivatives as potential ryanodine receptor modulators 被引量:1
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作者 yan zhang Yuxin Li +3 位作者 Huan Li Junfeng Shang Zhengming Li Baolei Wang 《Chinese Chemical Letters》 SCIE CAS CSCD 2022年第1期501-507,共7页
With the aim of discovering new bioactive pesticides for crop protection,a series of novel sulfidecontaining amide derivatives A were efficiently synthesized via a strategy of modifying the“amide”structure of anthra... With the aim of discovering new bioactive pesticides for crop protection,a series of novel sulfidecontaining amide derivatives A were efficiently synthesized via a strategy of modifying the“amide”structure of anthranilic diamide insecticides.The single-crystal structures of A2-3 and A4-5 were firstly reported.The bioassay results showed that most of the synthesized compounds display moderate to high insecticidal activities.Particularly,some sulfone-containing compounds,e.g.,A2-3,A3-3 and A6-3,not only possessed favorable lethality rate(50%–100%)against P.xylostella at a concentration of 0.1 mg/L,but also held good activities towards a variety of agricultural pests such as M.separata,C.pipiens pallen,H.armigera and O.nubilalis;the larvicidal activities of A4-1 and A6-1 towards P.xylostella were close to that of chlorantraniliprole at 0.01 mg/L.The calcium imaging experiments revealed that the representative compounds A2-3 and A6-3 are potential ryanodine receptor(RyR)modulators.The structure–activity relationships were discussed in detail.These results provide useful information for further design and development of novel insecticides. 展开更多
关键词 Sulfide-containing amide derivatives SULFOXIDE SULFONE Insecticidal activities Calcium channel
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The First Isolation of a Cyanophage-Synechococcus System from the East China Sea 被引量:1
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作者 yan zhang Min Xu +1 位作者 Yijun Zhao Kai Cheng 《Virologica Sinica》 SCIE CAS CSCD 2013年第5期260-265,共6页
A cyanophage strain and its host Synechococcus were isolated from the East China Sea. The host Synechococcus sp. S J01 was characterized by its 16S rRNA, ITS, andpsbA gene sequences as well as by its morphological app... A cyanophage strain and its host Synechococcus were isolated from the East China Sea. The host Synechococcus sp. S J01 was characterized by its 16S rRNA, ITS, andpsbA gene sequences as well as by its morphological appearance and pigmentation. The cyanophage, strain S-SJ2, was able to cause a lytic infection of the coastal Synechococcus. TEM of negative-stained specimens showed that the phage isolate has an isometric head with a diameter of 68 nm and a long tail with a length of 280 nm. The cyanophage-Synechococcus system from the East China Sea shares many properties with other marine cyanophage-Synechocoecus systems worldwide. 展开更多
关键词 Synechococcus sp. CYANOPHAGE East China Sea
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Mechanism of Hypoxia-Inducible Factor 1 Alpha Regulation of Apoptosis in Human Spermatozoa
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作者 Xinge Liu Linfeng Mo +5 位作者 Yinjia zhang Liangzhao Liu yan zhang Yonghua He Mingxue zhang Lishan Tang 《Advances in Reproductive Sciences》 2025年第1期49-62,共14页
Objective: To investigate the specific mechanism of hypoxia-inducible factor 1 alpha (HIF-1α) in the regulation of human sperm apoptosis, and to provide a new theoretical reference and scientific basis for the diagno... Objective: To investigate the specific mechanism of hypoxia-inducible factor 1 alpha (HIF-1α) in the regulation of human sperm apoptosis, and to provide a new theoretical reference and scientific basis for the diagnosis and treatment of asthenospermia and other related conditions. Methods: Semen samples were categorized into the normal group and asthenospermia group based on sperm motility criteria. HIF-1α interfering agent cobalt chloride (CoCl2) and guanylate cyclase activator (Lificiguat, YC-1) were added respectively, with a control group established accordingly. Sperm motility (using anterior viability rate as an index), apoptosis level, ATP level, mitochondrial membrane potential, and reactive oxygen species (ROS) level were measured. The expression levels of HIF-1α, p-PI3K, and Bcl-2 in the samples were analyzed using Western blotting. Results: Following CoCl2 treatment, there was a significant increase in sperm apoptosis compared to the normal control group (12.51% ± 2.50% VS 11.15% ± 2.42%);additionally, sperm motility (45.34% ± 3.37% VS 51.36% ± 11.68%), ATP production (11.51 ± 2.87 nM/µL VS 14.99 ± 2.83 nM/µL), ROS levels, and mitochondrial membrane potential all decreased significantly (all P α and p-PI3K increased significantly while Bcl-2 expression decreased (all P α in the YC-1 treatment group were decreased, and the expression level of Bcl-2 was increased (all P α can influence human sperm apoptosis and motility through the PI3K signaling pathway. 展开更多
关键词 Hypoxia Inducible Factor-1α APOPTOSIS Sperm Motility ASTHENOSPERMIA
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A Review of Bicuspid Aortic Valve Anomaly
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作者 Wei Hu Rubing Wang +8 位作者 yan zhang Yuxin Qi Jibin Xu Jingjing Wang Junnan Wang Weiqing Pu Yufeng zhang Zhinong Wang Yudi Liu 《International Journal of Clinical Medicine》 2025年第1期112-126,共15页
Bicuspid aortic valve (BAV) is a common congenital heart valve disease, often accompanied by aortic valve stenosis or regurgitation, infective endocarditis, and aortic diseases such as aortic dilation and dissection. ... Bicuspid aortic valve (BAV) is a common congenital heart valve disease, often accompanied by aortic valve stenosis or regurgitation, infective endocarditis, and aortic diseases such as aortic dilation and dissection. This article aims to review the definition, pathogenesis and genetic basis, classification methods, clinical features and current status of research and treatment and prognosis of BAV, and provide reference for the diagnosis and treatment of BAV. The content and structure of this article are as follows: The first part introduces the definition of BAV;The second part introduces the etiology and classification methods of BAV;The third part briefly describes the clinical manifestations and diagnosis of BAV;The fourth part discusses the treatment strategies and prognosis prediction of BAV;Finally, the article summarizes and looks forward to the future research directions. 展开更多
关键词 Bicuspid Aortic Valve Congenital Heart Disease Aortic Valve Disease Transcatheter Aortic Valve Replacement
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Photochemistry of Potassium Ferrocyanide and its Reaction with Uridine 5′-monophosphate in Aqueous Solution under Ultraviolet Irradiation
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作者 Song-qiu yang yan zhang yan-ni Wang 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2022年第5期764-773,I0014-I0022,I0011,I0012,共21页
The photochemical reaction of potassium ferrocyanide(K_(4)Fe(CN)_(6))exhibits excitation wavelength dependence and non-Kasha rule behavior.In this study,the excited-state dynamics of K_(4)Fe(CN)_(6) were studied by tr... The photochemical reaction of potassium ferrocyanide(K_(4)Fe(CN)_(6))exhibits excitation wavelength dependence and non-Kasha rule behavior.In this study,the excited-state dynamics of K_(4)Fe(CN)_(6) were studied by transient absorption spectroscopy.Excited state electron detachment(ESED)and photoaquation reactions were clarified by comparing the results of 260,320,340,and 350 nm excitations.ESED is the path to generate a hydrated electron(e^(−)_(aq)).ESED energy barrier varies with the excited state,and it occurs even at the first singlet excited state(^(1)T_(1g)).The ^(1)T_(1g) state shows∼0.2 ps lifetime and converts into triplet[Fe(CN)_(6)]4−by intersystem crossing.Subsequently,3Fe(CN)_(5)]^(3-)appears after one CN−ligand is ejected.In sequence,H2O attacksFe(CN)_(5)]^(3-)to generate[Fe(CN)_(5)H_(2)O]^(3−)with a time constant of approximately 20 ps.The ^(1)T_(1g) state and e−aq exhibit strong reducing power.The addition of uridine 5′-monophosphate(UMP)to the K_(4)Fe(CN)_(6) solution decrease the yield of e−aq and reduce the lifetimes of the e−aq and ^(1)T_(1g) state.The obtained reaction rate constant of ^(1)T_(1g) state and UMP is 1.7×10^(14)(mol/L)^(−1)·s^(−1),and the e−aq attachment to UMP is∼8×10^(9)(mol/L)^(−1)·s^(−1).Our results indicate that the reductive damage of K_(4)Fe(CN)_(6) solution to nucleic acids under ultraviolet irradiation cannot be neglected. 展开更多
关键词 Ultrafast spectroscopy Photoaquation Electron detachment Excited state dynamics Ferrous hexacyanides
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Anthocyanin Profiles in Grape Berry Skins of Different Species ofWine Grapes in Shanxi,China
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作者 Wei Tan Mingxiu Xu +5 位作者 Siqi Xie yan zhang Shuai Wu Qinyan Zou Qifeng Zhao Qingliang Li 《Phyton-International Journal of Experimental Botany》 SCIE 2021年第2期553-570,共18页
To understand the anthocyanin characteristics of wine grape varieties,the anthocyanin composition and content of 31 wine grape varieties were analyzed to explore the use of anthocyanins as chemical fingerprints to dis... To understand the anthocyanin characteristics of wine grape varieties,the anthocyanin composition and content of 31 wine grape varieties were analyzed to explore the use of anthocyanins as chemical fingerprints to distinguish varieties.Results showed that a total of 21 anthocyanins were detected in the skins,including cyanidin,delphinidin,petunidin,peonidin and malvidin 3-monoglucosides(or 3,5-diglucosides)along with the corresponding acetyl and p-coumaroyl derivatives.The highest and lowest total amount of anthocyanins were detected in‘Ruby Cabernet’and‘Muscat Rouge’,respectively.In the 21 Vitis vinifera grapes,there were 3~11 monoglucoside anthocyanins detected,however,there were 4 to 9 monoglucoside anthocyanins and 1~7 diglucoside anthocyanins detected in the 10 other species of grapes.Except for‘Zhesexiang’‘Seibel Noir’,‘44-6-7-1’and‘Beibinghong’,the contents of diglucoside anthocyanins in the other six varieties accounted for more than 52%of the total anthocyanins.Except for‘Zhesexiang’,‘Muscat Rouge’and‘Beibinghong’,the content of methylated anthocyanins accounted for more than 75%of total anthocyanins.There were significant differences in the anthocyanin types and contents in the skins among V.vinifera and other grapes.The results of the principal component analysis and the cluster classification of 31 grape varieties(lines)were nearly consistent,which suggested that anthocyanins can be used as chemical fingerprints to distinguish wine grape varieties. 展开更多
关键词 ANTHOCYANIN cluster analysis principal component analysis wine grape
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Dynamically changing antineutrophil cytoplasmic antibodies in granulomatosis with polyangiitis:A case report
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作者 yan zhang Qiao-Ding Dai +3 位作者 Ji-An Wang Li-Ping Xu Qiang Chen yang-Zi Jin 《World Journal of Clinical Cases》 SCIE 2024年第16期2881-2886,共6页
BACKGROUND Granulomatosis with polyangiitis(GPA)is one of the most prevalent forms of the antineutrophil cytoplasmic antibody(ANCA)-associated vasculitis.GPA is characterized histologically by necrotizing granulomatou... BACKGROUND Granulomatosis with polyangiitis(GPA)is one of the most prevalent forms of the antineutrophil cytoplasmic antibody(ANCA)-associated vasculitis.GPA is characterized histologically by necrotizing granulomatous inflammation in addition to vasculitis.The diagnosis of GPA depends on clinical presentation,serological evidence of a positive ANCA,and/or histological evidence of necrotizing vasculitis or granulomatous destructive parenchymal inflammation.Cytoplasmic ANCA(c-ANCA)is positive in 65%-75% of GPA patients,accompanied by proteinase 3(PR3),the main target antigen of c-ANCA,another 5% of GPA patients had negative ANCA.CASE SUMMARY The patient,a 52-year-old male,presented with unexplained nasal congestion,tinnitus,and hearing loss.After a duration of 4 months experiencing these symptoms,the patient subsequently developed fever and headache.The imaging examination revealed the presence of bilateral auricular mastoiditis and partial paranasal sinusitis,and the ANCA results were negative.The anti-infective therapy proved to be ineffective,but the patient's symptoms and fever were quickly relieved after 1 wk of treatment with methylprednisolone 40 mg once a day.However,after continuous use of methylprednisolone tablets for 3 months,the patient experienced a recurrence of fever accompanied by right-sided migraine,positive c-ANCA and PR3,and increased total protein in cerebrospinal fluid.The and cyclophosphamide 0.8 g monthly,the patient experienced alleviation of fever and headache.Additionally,the ANCA levels became negative and there has been no recurrence.CONCLUSION For GPA patients with negative ANCA,there is a potential for early missed diagnosis.The integration of histopathological results and multidisciplinary communication plays a crucial role in facilitating ANCA-negative GPA. 展开更多
关键词 Anti-neutrophil cytoplasmic antibodies Granulomatosis with polyangiitis Antineutrophil cytoplasmic antibodyassociated vasculitis Immunosuppressive therapy Case report
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新型氢储运技术发展及应用现状 被引量:1
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作者 张岩 王旭升 +4 位作者 林羲 晏嘉泽 孙玉杰 姜方 邹建新 《科技导报》 北大核心 2025年第7期67-78,共12页
重点分析了固态储氢、有机液态储氢、甲醇储氢和氨储氢等多种新型储运氢技术特点、发展现状、经济成本及关键技术瓶颈,探讨了其未来发展方向,并横向对比了不同氢储运技术的经济性水平与应用前景。当前,固态储氢技术已在部分领域实现示... 重点分析了固态储氢、有机液态储氢、甲醇储氢和氨储氢等多种新型储运氢技术特点、发展现状、经济成本及关键技术瓶颈,探讨了其未来发展方向,并横向对比了不同氢储运技术的经济性水平与应用前景。当前,固态储氢技术已在部分领域实现示范应用,但其大规模产业化仍面临高成本和高能耗等挑战。有机液态储氢技术虽然操作便捷,但受限于脱氢温度高、释氢速率低及对贵金属催化剂的依赖。绿色甲醇和绿氨储氢技术在能耗、安全性和经济性方面仍存在一定制约。不同储运技术各具优势与局限,需要综合考虑氢储运量、运输距离、安全性、碳排放及具体应用场景,以确定最优的技术路径和应用方案。 展开更多
关键词 新型氢储运技术 镁基固态储氢 有机液态储氢 甲醇储氢 氨储氢
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4′-N,N-二乙氨基-3-羟基苯并黄酮激发态分子内质子转移机制的溶剂极性效应——实验和理论研究
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作者 姜羊林 陈明卿 +4 位作者 梁民 尧奕歌 张燕 王鹏 张建平 《物理化学学报》 北大核心 2025年第2期116-124,共9页
激发态分子内质子转移(ESIPT)反应是一种重要的基础光化学反应,通常发生在具有分子内氢键的发色团中。3-羟基黄酮类衍生物(3-HFs)由于其广泛的天然来源和对环境极度敏感的荧光发光特性而备受关注。与3-HFs相比,4′-N,N-二乙氨基-3-羟基... 激发态分子内质子转移(ESIPT)反应是一种重要的基础光化学反应,通常发生在具有分子内氢键的发色团中。3-羟基黄酮类衍生物(3-HFs)由于其广泛的天然来源和对环境极度敏感的荧光发光特性而备受关注。与3-HFs相比,4′-N,N-二乙氨基-3-羟基黄酮(D-HBF)具有扩展的共轭体系和大幅红移的吸收特性,而最新研究表明,由于具有ESIPT特性,它可以用作环境极性敏感的生物荧光探针。本研究通过采用多种光谱和理论计算方法,系统研究了D-HBF在极性不同的三种非质子型溶剂(环己烷、乙醚和四氢呋喃)中的ESIPT反应机制。研究结果显示,在这三种溶剂中均能观测到D-HBF的ESIPT典型双发射峰,而这些峰的相对比率受溶剂极性的调控。荧光动力学分析揭示,随着溶剂极性的增加,激发态中正向和反向的质子转移反应速率都降低,同时反向质子转移变得更占优势。该研究还通过密度泛函理论和含时密度泛函理论计算,比较了三种溶剂中D-HBF的基态和激发态分子内氢键的键长和键角参数,确定了ESIPT反应是激发态分子内氢键增强机制。计算结果表明,增加溶剂极性会导致处于S1态的D-HBF分子的3-羟基伸缩振动红外吸收频率向高波数移动,这证明了相应的N^(*)态的分子内氢键减弱。此外,电子密度分析显示,引入在4′-位的强给电子官能团(4′-N,N-二乙氨基)使得D-HBF在激发态下具有典型的分子内电荷转移特征。最后,势能曲线计算结果表明,在激发态下质子转移更容易发生,而溶剂极性增加会导致更高的质子转移势垒,从而阻碍了相应的ESIPT反应。吉布斯自由能分析进一步表明,溶剂极性增加使激发态快速质子转移更倾向于向N^(*)态移动。这项研究为D-HBF类衍生物作为环境极性敏感的生物探针的应用提供了理论基础。 展开更多
关键词 4′-N N-二乙氨基-3-羟基苯并黄酮 激发态分子内质子转移 密度泛函理论/含时密度泛函理论 溶剂极性效应 荧光动力学
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国内外物理化学教材对比研究——电解质溶液
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作者 张岩 曹晓燕 +2 位作者 李一鸣 夏树伟 包木太 《大学化学》 2025年第9期303-309,共7页
溶液是化学学科的核心研究体系之一,电解质溶液是溶液体系的重要组成部分。本文选取了8本国内外代表性物理化学教材,以电解质溶液为研究对象,详细比较了不同教材中该部分的章节设置、内容安排,并对教材中的习题进行了介绍,期望为物理化... 溶液是化学学科的核心研究体系之一,电解质溶液是溶液体系的重要组成部分。本文选取了8本国内外代表性物理化学教材,以电解质溶液为研究对象,详细比较了不同教材中该部分的章节设置、内容安排,并对教材中的习题进行了介绍,期望为物理化学的教材编写和一线教学提供参考。 展开更多
关键词 物理化学 教材建设 对比研究 电解质溶液
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人工智能在海洋特色物理化学综合实验中的应用探索
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作者 张岩 周立敏 +1 位作者 曹晓燕 包木太 《大学化学》 2025年第9期118-125,共8页
本研究基于海洋特色物理化学实验教学,探索人工智能赋能实验教学的创新路径。介绍了知识图谱在系统化学习与跨学科知识方面的有效运用,并结合DeepSeek与Python开源大模型,提升了数据处理智能化水平,推动了实验教学智能化发展。
关键词 物理化学实验 人工智能 海洋特色 知识图谱 DeepSeek PYTHON
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耐低温水性聚氨酯胶黏剂的分子设计及性能研究 被引量:1
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作者 史翔 张艳朋 +3 位作者 张燕 闫旭焕 王中丽 耿建新 《高分子学报》 北大核心 2025年第4期644-652,共9页
针对太空技术、极地考察等高科技领域发展的需求,研究在低温环境下具有良好粘接性能的绿色胶黏剂具有重要意义.水性聚氨酯(WPU)胶黏剂以水为分散剂,是一种极具潜力的绿色胶黏剂材料.然而,目前针对WPU胶黏剂耐低温性能的研究仍较为缺乏.... 针对太空技术、极地考察等高科技领域发展的需求,研究在低温环境下具有良好粘接性能的绿色胶黏剂具有重要意义.水性聚氨酯(WPU)胶黏剂以水为分散剂,是一种极具潜力的绿色胶黏剂材料.然而,目前针对WPU胶黏剂耐低温性能的研究仍较为缺乏.本文以聚丙二醇(PPG)和异佛尔酮二异氰酸酯(IPDI)为主要合成原料、二羟甲基丙酸(DMPA)为亲水扩链剂、乙二胺(EDA)为小分子后扩链剂,通过调控DMPA质量分数和异氰酸根与羟基的初始摩尔数比值,制备了一系列具有玻璃化转变温度(T_(g))的WPU胶黏剂,并重点对T_(g)的调控及其与T剥离强度的关系进行了研究,获得了具有优异耐低温性能的WPU胶黏剂.所得该胶黏剂的T_(g)最低可达-35℃,以芳纶机织布为基材测得的T剥离强度达到2.69N/mm.相应胶条的断裂强度可达5.51MPa,弹性模量可达296.64MPa,断裂伸长率可达504%,体现出优异的机械柔性和韧性.相关结果对新型耐低温绿色胶黏剂材料的研发及其在相关领域的应用具有重要的参考价值. 展开更多
关键词 水性聚氨酯 胶黏剂 耐低温性能 力学性能
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智能药品研磨机温度控制系统设计与实现
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作者 王星阳 张燕 +2 位作者 李明哲 刘伸 高朕帝 《新疆钢铁》 2025年第3期199-201,共3页
本文设计了一套基于STM32单片机的药品低温智能研磨系统。该系统在研磨机的内部和外部都装有温度传感器,这些传感器负责实时监控研磨机的温度状态。为了维持研磨机工作在一个适宜的温度范围内,该系统还引入了水循环冷却机制,通过外部水... 本文设计了一套基于STM32单片机的药品低温智能研磨系统。该系统在研磨机的内部和外部都装有温度传感器,这些传感器负责实时监控研磨机的温度状态。为了维持研磨机工作在一个适宜的温度范围内,该系统还引入了水循环冷却机制,通过外部水循环的方式,将研磨机机壁的热量传递给冷水,有效地降低研磨机机壁的热量,从而使研磨机内部热量降低。此外,该系统还具备高温自动断电、低温自启动的功能:当检测到研磨机温度过高时,系统会自动切断内部电源,停止研磨,同时不断进行外部水循环,降低研磨机温度,减少药品中有效成分的挥发;当温度下降到工作温度范围内时,系统又会自动恢复内部供电,使研磨机继续工作。 展开更多
关键词 智能研磨 温度控制 STM32
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An Integrated Framework of Grasp Detection and Imitation Learning for Space Robotics Applications 被引量:1
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作者 Yuming Ning Tuanjie Li +3 位作者 Yulin zhang Ziang Li Wenqian Du yan zhang 《Chinese Journal of Mechanical Engineering》 2025年第4期316-335,共20页
Robots are key to expanding the scope of space applications.The end-to-end training for robot vision-based detection and precision operations is challenging owing to constraints such as extreme environments and high c... Robots are key to expanding the scope of space applications.The end-to-end training for robot vision-based detection and precision operations is challenging owing to constraints such as extreme environments and high computational overhead.This study proposes a lightweight integrated framework for grasp detection and imitation learning,named GD-IL;it comprises a grasp detection algorithm based on manipulability and Gaussian mixture model(manipulability-GMM),and a grasp trajectory generation algorithm based on a two-stage robot imitation learning algorithm(TS-RIL).In the manipulability-GMM algorithm,we apply GMM clustering and ellipse regression to the object point cloud,propose two judgment criteria to generate multiple candidate grasp bounding boxes for the robot,and use manipulability as a metric for selecting the optimal grasp bounding box.The stages of the TS-RIL algorithm are grasp trajectory learning and robot pose optimization.In the first stage,the robot grasp trajectory is characterized using a second-order dynamic movement primitive model and Gaussian mixture regression(GMM).By adjusting the function form of the forcing term,the robot closely approximates the target-grasping trajectory.In the second stage,a robot pose optimization model is built based on the derived pose error formula and manipulability metric.This model allows the robot to adjust its configuration in real time while grasping,thereby effectively avoiding singularities.Finally,an algorithm verification platform is developed based on a Robot Operating System and a series of comparative experiments are conducted in real-world scenarios.The experimental results demonstrate that GD-IL significantly improves the effectiveness and robustness of grasp detection and trajectory imitation learning,outperforming existing state-of-the-art methods in execution efficiency,manipulability,and success rate. 展开更多
关键词 Grasp detection Robot imitation learning MANIPULABILITY Dynamic movement primitives Gaussian mixture model and Gaussian mixture regression Pose optimization
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Cumulative effects of stress-sensitivity factors on depressive symptoms and suicide risk:A prospective study 被引量:1
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作者 Xue-Mei Qin Meng-Qi Xu +20 位作者 Ya-Qi Qin Fang-Zhou Shao Mo-Han Ma Wen-Wen Ou Guan-Yi Lv Qian-Qianzhang Wen-Tao Chen Xiao-Tian Zhao Ao-Qian Deng Jin-Tao Xiong Ling-Si Zeng Yi-Lin Peng Mei Huang Shu-Yin Xu Mei Liao Li zhang Ling-Jiang Li Yu-Meng Ju Jin Liu Bang-Shan Liu yan zhang 《World Journal of Psychiatry》 2025年第2期173-185,共13页
BACKGROUND Sensitivity to stress is essential in the onset,clinical symptoms,course,and prognosis of major depressive disorder(MDD).Meanwhile,it was unclear how variously classified but connected stress-sensitivity va... BACKGROUND Sensitivity to stress is essential in the onset,clinical symptoms,course,and prognosis of major depressive disorder(MDD).Meanwhile,it was unclear how variously classified but connected stress-sensitivity variables affect MDD.We hypothesize that high-level trait-and state-related stress-sensitivity factors may have different cumulative effects on the clinical symptoms and follow-up outcomes of MDD.AIM To investigate how stress-sensitivity factors added up and affected MDD clinical symptoms and follow-up results.METHODS In this prospective study,281 MDD patients were enrolled from a tertiary care setting.High-level stress-sensitivity factors were classified as trait anxiety,state anxiety,perceived stress,and neuroticism,with a total score in the top quartile of the research cohort.The cumulative effects of stress-sensitivity factors on cognitive dysfunction,disability and functional impairment,suicide risk,and depressive and anxiety symptoms were examined using an analysis of variance with linear trend analysis.Correlations were investigated further using multiple regression analysis.RESULTS Regarding high-level stress-sensitivity factors,53.40%of patients had at least one at baseline,and 29.61%had two or more.Four high-level stress-sensitivity components had significant cumulative impacts on MDD symptoms at baseline(all P<0.001).Perceived stress predicted the greatest effect sizes of state-related factors on depressive symptoms(partialη^(2)=0.153;standardizedβ=0.195;P<0.05).The follow-up outcomes were significantly impacted only by the high-level trait-related components,mainly when it came to depressive symptoms and suicide risk,which were predicted by trait anxiety and neuroticism,respectively(partialη^(2)=0.204 and 0.156;standardizedβ=0.247 and 0.392;P<0.05).CONCLUSION To enhance outcomes of MDD and lower the suicide risk,screening for stress-sensitivity factors and considering multifaceted measures,mainly focusing on trait-related ones,should be addressed clinically. 展开更多
关键词 Major depressive disorder Stress sensitivity Depressive symptoms Suicide risk Cumulative effect
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