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Autophagy-targeting modulation to promote peripheral nerve regeneration
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作者 Yan Chen Hongxia Deng nannan zhang 《Neural Regeneration Research》 SCIE CAS 2025年第7期1864-1882,共19页
Nerve regeneration following traumatic peripheral nerve injuries and neuropathies is a complex process modulated by diverse factors and intricate molecular mechanisms.Past studies have focused on factors that stimulat... Nerve regeneration following traumatic peripheral nerve injuries and neuropathies is a complex process modulated by diverse factors and intricate molecular mechanisms.Past studies have focused on factors that stimulate axonal outgrowth and myelin regeneration.However,recent studies have highlighted the pivotal role of autophagy in peripheral nerve regeneration,particularly in the context of traumatic injuries.Consequently,autophagy-targeting modulation has emerged as a promising therapeutic approach to enhancing peripheral nerve regeneration.Our current understanding suggests that activating autophagy facilitates the rapid clearance of damaged axons and myelin sheaths,thereby enhancing neuronal survival and mitigating injury-induced oxidative stress and inflammation.These actions collectively contribute to creating a favorable microenvironment for structural and functional nerve regeneration.A range of autophagyinducing drugs and interventions have demonstrated beneficial effects in alleviating peripheral neuropathy and promoting nerve regeneration in preclinical models of traumatic peripheral nerve injuries.This review delves into the regulation of autophagy in cell types involved in peripheral nerve regeneration,summarizing the potential drugs and interventions that can be harnessed to promote this process.We hope that our review will offer novel insights and perspectives on the exploitation of autophagy pathways in the treatment of peripheral nerve injuries and neuropathies. 展开更多
关键词 AUTOPHAGY autophagy related genes Charcot–Marie–Tooth diseases diabetic peripheral neuropathy METFORMIN MYELINATION peripheral nerve injury Schwann cells sciatic nerve Wallerian degeneration
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DNA damage response-related immune activation signature predicts the response to immune checkpoint inhibitors: from gastrointestinal cancer analysis to pan-cancer validation
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作者 Junya Yan Shibo Wang +20 位作者 Jing zhang Qiangqiang Yuan Xianchun Gao nannan zhang Yan Pan Haohao zhang Kun Liu Jun Yu Linbin Lu Hui Liu Xiaoliang Gao Sheng Zhao Wenyao zhang Abudurousuli Reyila Yu Qi Qiujin zhang Shundong Cang Yuanyuan Lu Yanglin Pan Yan Kong Yongzhan Nie 《Cancer Biology & Medicine》 SCIE CAS CSCD 2024年第3期252-266,共15页
Objective: DNA damage response(DDR) deficiency has emerged as a prominent determinant of tumor immunogenicity. This study aimed to construct a DDR-related immune activation(DRIA) signature and evaluate the predictive ... Objective: DNA damage response(DDR) deficiency has emerged as a prominent determinant of tumor immunogenicity. This study aimed to construct a DDR-related immune activation(DRIA) signature and evaluate the predictive accuracy of the DRIA signature for response to immune checkpoint inhibitor(ICI) therapy in gastrointestinal(GI) cancer.Methods: A DRIA signature was established based on two previously reported DNA damage immune response assays. Clinical and gene expression data from two published GI cancer cohorts were used to assess and validate the association between the DRIA score and response to ICI therapy. The predictive accuracy of the DRIA score was validated based on one ICI-treated melanoma and three pan-cancer published cohorts.Results: The DRIA signature includes three genes(CXCL10, IDO1, and IFI44L). In the discovery cancer cohort, DRIA-high patients with gastric cancer achieved a higher response rate to ICI therapy than DRIA-low patients(81.8% vs. 8.8%;P < 0.001), and the predictive accuracy of the DRIA score [area under the receiver operating characteristic curve(AUC) = 0.845] was superior to the predictive accuracy of PD-L1 expression, tumor mutational burden, microsatellite instability, and Epstein–Barr virus status. The validation cohort demonstrated that the DRIA score identified responders with microsatellite-stable colorectal and pancreatic adenocarcinoma who received dual PD-1 and CTLA-4 blockade with radiation therapy. Furthermore, the predictive performance of the DRIA score was shown to be robust through an extended validation in melanoma, urothelial cancer, and pan-cancer.Conclusions: The DRIA signature has superior and robust predictive accuracy for the efficacy of ICI therapy in GI cancer and pancancer, indicating that the DRIA signature may serve as a powerful biomarker for guiding ICI therapy decisions. 展开更多
关键词 DNA damage response-related immune activation immune checkpoint inhibitors biomarker gastrointestinal cancer pan-cancer
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Frequent recombination in Cynoglossus abbreviatus(Pleuronectiformes:Cynoglossidae)ribosomal 18S rDNA
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作者 Li Gong Tingqi Jiang +3 位作者 Bilin Hu Kaixin Wang nannan zhang Zengliang Miao 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第8期98-103,共6页
The conventional theory of concerted evolution has been used to explain the lack of sequence variation in ribosomal RNA(rRNA)genes across diverse eukaryotic species.However,recent investigations into rRNA genes in fla... The conventional theory of concerted evolution has been used to explain the lack of sequence variation in ribosomal RNA(rRNA)genes across diverse eukaryotic species.However,recent investigations into rRNA genes in flatfish genome have resulted in controversial findings.This study focuses on 18S rRNA genes of the widely distributed tongue sole,Cynoglossus abbreviatus(Pleuronectiformes:Cynoglossidae),aiming to explore sequence polymorphism.Five distinct 18S rDNA sequence types(Type A,B,R1,R2,and R3)were identified,suggesting a departure from concerted evolution.A combination of general criteria and variations in highly conserved regions were employed to detect pseudogenes.The results pinpointed Type A sequences as potential pseudogenes due to significant sequence variations and deviations in secondary structure within highly conserved regions.Three types(Type R1,R2,and R3)were identified as recombinants between Type A and B sequences,with simple crossing over and gene conversion as the most likely recombination mechanisms.These findings not only contribute to rRNA pseudogene identification but also shed light on the evolutionary dynamics of rRNA genes in teleost genomes. 展开更多
关键词 ribosomal RNA tongue sole non-concerted evolution PSEUDOGENE crossing over gene conversion
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有富电子镍位点的耐酸金属间化合物CaNi_(2)Si_(2)催化剂用于不饱和有机酸酐/酸的水相加氢
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作者 刘诗瑶 巩玉同 +4 位作者 杨晓 张楠楠 刘会斌 梁长海 陈霄 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2023年第7期260-272,共13页
顺酐水相加氢制备下游产物丁二酸,是一种合成生物可降解塑料聚丁二酸丁二醇酯的重要单体.在水相体系中,顺酐迅速水解生成顺丁烯二酸,表现出较强的酸性,对催化剂耐酸稳定性要求较高.贵金属催化剂通常表现出较高的顺酐加氢活性,但由于其... 顺酐水相加氢制备下游产物丁二酸,是一种合成生物可降解塑料聚丁二酸丁二醇酯的重要单体.在水相体系中,顺酐迅速水解生成顺丁烯二酸,表现出较强的酸性,对催化剂耐酸稳定性要求较高.贵金属催化剂通常表现出较高的顺酐加氢活性,但由于其与底物分子结合能力较强,容易生成深度加氢或氢解产物,并且贵金属高昂的价格也限制了其进一步应用.此外,工业上常用的负载型Ni基催化剂的活性和稳定性也有待进一步提高.因此,在顺酐水相直接加氢生成丁二酸的过程中开发高活性和高稳定性的非贵金属基催化剂具有重要意义.金属硅化物作为一种新型的金属间化合物催化材料,常作为非均相催化剂应用,尤其对涉氢反应表现出较高的活性和选择性,并且由于硅原子的掺入,调变了活性位点的几何和电子结构,使其展现出较好的催化活性、耐酸碱腐蚀性和热稳定性,有望用于顺酐直接水相加氢反应制备丁二酸.本文采用新型低温熔盐技术成功制备了一种单相的、元素分散均匀以及高比表的CaNi_(2)Si_(2)金属间化合物纳米催化剂,并将其应用于顺酐连续水相加氢制备丁二酸的反应体系中,可以有效解决该体系存在的瓶颈问题.采用X射线衍射Rietveld精修技术、X射线光电子能谱深度剖析、紫外光电子能谱和态密度分析等手段对CaNi_(2)Si_(2)催化剂的几何和电子结构进行剖析.并采用模型化合物丙烯酸原位漫反射傅里叶变换红外光谱、原位程序升温脱附/表面反应及密度泛函理论计算等研究了CaNi_(2)Si_(2)催化顺酐加氢反应机理,并剖析构效关系.结果表明CaNi_(2)Si_(2)催化剂中电子由Ca向Ni和Si发生转移,并证明了这种富电子Ni活性位点的协同作用有利于其对底物分子中C=C键选择性吸附和H_(2)的活化,从而使其展现出较好的目标产物丁二酸的选择性.在3 MPa,120℃,接触时间5.4 gcat/(mmolreactant·min^(‒1))条件下,丁二酸产率可达到100%.此外,相比于负载型Ni/SBA-15催化剂(51.90 kJ/mol),CaNi_(2)Si_(2)展现出更低的表观活化能(46.39 kJ/mol),从本征活性证明了其作为顺酐水相加氢催化剂的优势.稳定性测试结果表明,与Ni/SBA-15相比,由于CaNi_(2)Si_(2)中Ni特殊的配位环境和电子结构抑制了羧酸盐的形成,有效减少了活性金属Ni位点的流失,从而有效的提高了其在顺酐水溶液(2 wt%,pH=1.51)中的耐酸腐蚀性能,使其表现出高活性的同时具有较好稳定性,在一定程度上可替代贵金属催化剂.同时,底物扩展实验也证明了CaNi_(2)Si_(2)作为一种催化新材料在不饱和链状或环状有机酸/酸酐的加氢性能反应中均能展现出较好的活性,说明了CaNi_(2)Si_(2)作为非贵金属催化剂在酸酐加氢领域具有巨大潜力.总之,金属硅化物的精细设计和结构调控将为顺酐加氢催化剂的可控优化提供重要参考,并为设计高效稳定的苛刻反应中选择性加氢催化剂提供新的思路. 展开更多
关键词 CaNi_(2)Si_(2) 金属间化合物 富电子镍活性位点 选择性加氢 丁二酸
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Comparative mitochondrial genome analysis of Cynoglossidae(Teleost:Pleuronectiformes)and phylogenetic implications
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作者 Bilin Hu Tingqi Jiang +7 位作者 Liming Wei nannan zhang Kaixin Wang Liqin Liu Bingjian Liu Jing Liu Zhenming Lü Li Gong 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第11期69-80,共12页
Generally,a teleostean group(e.g.,family or genus)owns one type or a set of similar mitochondrial gene arrangement.It is interesting,however,that four different types of gene arrangement have been found in the mitocho... Generally,a teleostean group(e.g.,family or genus)owns one type or a set of similar mitochondrial gene arrangement.It is interesting,however,that four different types of gene arrangement have been found in the mitochondrial genome(mitogenome)of Cynoglossidae species.So far,the possible mechanisms of mitogenomic gene rearrangement and its potential implications have aroused widespread attention and caused lots of controversy.Here,a total of 21 Cynoglossidae mitogenomes and a newly sequenced mitogenome of Cynoglossus puncticpes(Pleuronectiformes:Cynoglossidae)were compared.The length ranges from 16417 bp to 18369 bp,which is mainly caused by the length heteroplasmy of control region(CR).Further analysis reveals that the difference of tandem repeats acts as a determining factor resulting in the length heterogeneity.Like most gene rearrangements of Cynoglossinae mitogenomes,tRNA-Gln gene encoded by the L-strand has translocated to the H-strand(Q inversion),accompanied by the translocation of CR in C.puncticpes mitogenome.The typical IQM order(tRNA-Ile-Gln-Met)changed to QIM order.Tandem duplication/random loss and mitochondrial recombination were accepted as the most possible models to account for the rearrangements in C.puncticpes mitogenome.Phylogenetic trees showed a strong correlation between the gap spacer in the rearranged QIM area and phylogeny,which provides a fresh idea for phylogenetic studies in future. 展开更多
关键词 MITOGENOME gene rearrangement tandem duplication/random loss mitochondrial inversion control region phylogenetic study
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Fault diagnosis of rolling bearings with noise signal based on modified kernel principal component analysis and DC‐ResNet
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作者 Yunji Zhao Menglin Zhou +1 位作者 Xiaozhuo Xu nannan zhang 《CAAI Transactions on Intelligence Technology》 SCIE EI 2023年第3期1014-1028,共15页
In view of the influence of aliasing noise on the effectiveness and accuracy of bearing fault diagnosis,a bearing fault diagnosis algorithm based on the spatial decoupling method of modified kernel principal component... In view of the influence of aliasing noise on the effectiveness and accuracy of bearing fault diagnosis,a bearing fault diagnosis algorithm based on the spatial decoupling method of modified kernel principal component analysis(MKPCA)and the residual network with deformable convolution(DC‐ResNet)is innovatively proposed.Firstly,the Gaussian noise with different signal‐to‐noise ratios(SNRs)is added to the data to simulate the different degrees of noise in the actual data acquisition process.The MKPCA is used to project the fault signal with different SNRs in the kernel space to reduce the data dimension and eliminate some noise effects.Finally,the DC‐ResNet model is used to further filter the noise effects and fully extract the fault features through the training of the preprocessed data.The proposed algorithm is tested on the Case Western Reserve University(CWRU)and Xi'an Jiaotong University and Changxing Sumyoung Technology Co.,Ltd.(XJTU‐SY)bearing data sets with different SNR noise.The fault diagnosis accuracy can reach 100%within 30 min,which has better performance than most of the existing methods.The experimental results show that the algorithm has an excellent effect on accuracy and computation complexity under different noise levels. 展开更多
关键词 artificial intelligence CLASSIFICATION deep learning fault feature extraction
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Research on Identification Method of Apple Diseases in Southern Xinjiang Based on Deep Learning and Its System Implementation
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作者 Peng QIN nannan zhang +1 位作者 Rong WU Lijun GAO 《Agricultural Biotechnology》 CAS 2023年第5期78-82,共5页
Apple disease samples were collected from the southern Xinjiang and annotated to design a convolutional neural network model based on deep learning.The accuracy and robustness of the model was improved through trainin... Apple disease samples were collected from the southern Xinjiang and annotated to design a convolutional neural network model based on deep learning.The accuracy and robustness of the model was improved through training and optimization algorithms,and a complete apple disease identification system was developed with the model as the core,and evaluated for its performance in terms of accuracy,recall rate and speed.This study provides a reliable AI-based apple disease diagnosis solution for the apple planting industry in the southern Xinjiang,hoping to help farmers better manage and protect crop health. 展开更多
关键词 Deep learning Convolutional neural network Apple disease identification Southern Xinjiang System implementation
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Predictive values of multidetector-row computed tomography combined with serum tumor biomarkers in preoperative lymph node metastasis of gastric cancer 被引量:12
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作者 Huihui Bai Jingyu Deng +4 位作者 nannan zhang Huifang Liu Wenting He Jinyuan Liu Han Liang 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2019年第3期453-462,共10页
Objective: Multidetector-row computed tomography(MDCT) and serum tumor biomarkers are commonly used to evaluate the preoperative lymph node metastasis and the clinical staging of gastric cancer(GC). This study intends... Objective: Multidetector-row computed tomography(MDCT) and serum tumor biomarkers are commonly used to evaluate the preoperative lymph node metastasis and the clinical staging of gastric cancer(GC). This study intends to evaluate the clinical predictive value of MDCT and serum tumor biomarkers in lymph node metastasis of GC.Methods: The clinicopathologic data of 445 GC patients who underwent radical gastrectomy were retrospectively analyzed to evaluate the diagnostic value of MDCT and serum tumor biomarkers in lymph node metastatic staging of GC before surgery.Results: With the multinomial logistic regression analysis, the independent relative factors of lymph node metastasis of GC were identified as tumor size, depth of tumor invasion, vessel invasion, vascular embolus, and soft tissue invasion. The optimal critical value of the short diameter of lymph nodes detected by MDCT scanning for evaluation of preoperative lymph node metastasis was 6.0 mm, with 75.7% as predictive accuracy of lymph node metastasis compared to the postoperative pathological results of GC patients. In addition, the critical value of the short diameter of lymph nodes combined with serum tumor biomarkers [including carbohydrate antigen(CA)-724 and CA-199] could show an enhancement of predictive sensitivity of lymph node metastasis(up to 89.3%) before surgery.Conclusions: MDCT combined with serum tumor biomarkers should be adopted to improve preoperative sensitivity and accuracy of lymph node metastasis for GC patients. 展开更多
关键词 GASTRIC cancer MDCT SERUM TUMOR biomarkers PREOPERATIVE
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Prognostic impact of D2-plus lymphadenectomy and optimal extent of lymphadenectomy in advanced gastric antral carcinoma: Propensity score matching analysis 被引量:9
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作者 Weilin Sun Jingyu Deng +8 位作者 nannan zhang Huifang Liu Jinyuan Liu Pengfei Gu Yingxin Du Zizhen Wu Wenting He Pengliang Wang Han Liang 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2020年第1期51-61,共11页
Objective: To investigate the prognostic impact of D2-plus lymphadenectomy including the posterior(No. 8 p,No. 12 b/p, No. 13, and No. 14 v), and para-aortic(No. 16 a2, and No. 16 b1) lymph nodes(LNs) in subtotal gast... Objective: To investigate the prognostic impact of D2-plus lymphadenectomy including the posterior(No. 8 p,No. 12 b/p, No. 13, and No. 14 v), and para-aortic(No. 16 a2, and No. 16 b1) lymph nodes(LNs) in subtotal gastrectomy for advanced gastric antral carcinoma.Methods: A total of 203 patients with advanced gastric cancer(GC) located in the antrum, who underwent R0 gastrectomy with D2 or D2-plus lymphadenectomy between January 2003 and December 2011 were enrolled.Propensity score matching was used to reduce the strength of the confounding factors to accurately evaluate prognoses. The therapeutic value index(TVI) was calculate to evaluate the survival benefit of dissecting each LN station.Results: Of 102 patients with D2-plus lymphadenectomy, 21(20.59%) were pathologically identified as having LN metastases beyond the extent of D2 lymphadenectomy. After matching, the overall survival(OS) was significantly better in the D2-plus than the D2 group(P=0.030). In the multivariate survival analysis, D2-plus lymphadenectomy(hazard ratio, 0.516;P=0.006) was confirmed to significantly improve the survival rate. In the logistic regression analysis, p N stage [odds ratio(OR), 2.533;95% confidence interval(95% CI), 1.368-4.691;P=0.003] and extent of LNs metastasis(OR, 5.965;95% CI, 1.335-26.650;P=0.019) were identified as independent risk factors for LN metastases beyond the extent of D2 lymphadenectomy. The TVI of patient with metastasis to LNs station was 7.1(No. 8p), 5.7(No. 12p), 5.1(No. 13), and 7.1(both No. 16a2 and No. 16b1), respectively.Conclusions: D2-plus lymphadenectomy may improve the prognoses of some patients with advanced GC located in the antrum, especially for No. 8p, No. 12b, No. 13, and No. 16. 展开更多
关键词 STOMACH NEOPLASM LYMPHADENECTOMY prognosis metastasis
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727例胃癌根治术标本淋巴结精细分拣的临床价值探讨 被引量:10
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作者 张楠楠 邓靖宇 +5 位作者 何文婷 刘勇 王学军 丁学伟 张汝鹏 梁寒 《中国肿瘤临床》 CAS CSCD 北大核心 2019年第1期22-27,共6页
目的:探讨胃癌根治术标本中淋巴结精细分拣的临床应用价值。方法:回顾性分析2016年1月至2017年12月就诊于天津医科大学肿瘤医院实施胃癌根治术的727例胃癌患者临床病理资料,按照手术切除标本中淋巴结分拣方式分为精细淋巴结分拣组和区... 目的:探讨胃癌根治术标本中淋巴结精细分拣的临床应用价值。方法:回顾性分析2016年1月至2017年12月就诊于天津医科大学肿瘤医院实施胃癌根治术的727例胃癌患者临床病理资料,按照手术切除标本中淋巴结分拣方式分为精细淋巴结分拣组和区域淋巴结分拣组,分析两组患者送检淋巴结数目、转移淋巴结数目的差异并进行相关性分析比较。结果:两组患者的性别、年龄、肿瘤大小等因素间差异均无统计学意义(P>0.05),两组之间具有可比性。精细淋巴结分拣组患者淋巴结送检数目明显多于区域淋巴结分拣组(P<0.001)。在T分期、N分期以及TNM分期相同的情况下,精细淋巴结分拣组送检淋巴结数目显著多于区域淋巴结分拣组(P<0.001);精细淋巴结分拣组淋巴结转移数目也显著多于区域淋巴结分拣组(P<0.001)。此外,两组患者送检淋巴结数目与转移淋巴结数目均呈正相关,差异具有统计学意义(精细淋巴结分拣组r=0.181,P=0.023;区域淋巴结分拣组r=0.227,P<0.001),且精细淋巴结分拣组患者的送检淋巴结数目与转移淋巴结数目之间相关性弱于区域淋巴结分拣组患者。结论:胃癌根治术后精细淋巴结分拣可以提高送检淋巴结数目,提供精确的术后淋巴结分期,减少分期迁移,可以在临床上规范性推广。 展开更多
关键词 胃癌 淋巴结转移 预后
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Glial cell line-derived neurotrophic factor in brain repair after focal ischemic stroke 被引量:1
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作者 Zhe zhang nannan zhang Shinghua Ding 《Neural Regeneration Research》 SCIE CAS CSCD 2022年第8期1735-1736,共2页
Cerebral focal ischemic stroke(FIS)is a leading brain disorder associated with human debilitation and death.It is induced by the formation of a thrombus in the arteries that supply blood to the central nervous system.... Cerebral focal ischemic stroke(FIS)is a leading brain disorder associated with human debilitation and death.It is induced by the formation of a thrombus in the arteries that supply blood to the central nervous system.FIS patients may suddenly experience paralysis,impairment of speech and loss of vision.Most patients develop permanent disabilities.In the past decades,enormous efforts have been taken to develop FIS treatment strategies,but unfortunately,there is still a lack of effective ones for this disease.Currently,tissue plasminogen activator is the only Food and Drug Administration approved drug for FIS treatment,however,this method has limited application since it is only effective within 3-5 hours after the onset of FIS.Because of this,the recovery from FIS largely depends on self-brain repair and rehabilitation(Campbell et al.,2019). 展开更多
关键词 PARALYSIS ARTERIES suddenly
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Study on Detection of Pesticide Residues on Winter Jujube Surface by Near-infrared Spectroscopy Combined with PLS and SPA 被引量:2
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作者 Xiao zhang nannan zhang 《Agricultural Biotechnology》 CAS 2018年第5期222-226,228,共6页
With fresh winter jujube from the southern region of Xinjiang as the object of study, the method for detecting pesticide residues on winter jujube surface by near-infrared spectroscopy (NIR) combined with successive... With fresh winter jujube from the southern region of Xinjiang as the object of study, the method for detecting pesticide residues on winter jujube surface by near-infrared spectroscopy (NIR) combined with successive projections algorithm (SPA) and partial least squares (PLS) was investigated. The absorbance information of winter jujube sample surface was obtained through NIR technology, for the building of a full-wave band PLS model of fresh winter jujube sample sprayed with different concentrations of pesticide (taking chlorpyrifos as an example) as well as an SPA-PLS model which was built with the characteristic wavelengths extracted with SPA as the input variables for PLS, and the prediction precision of the two kinds of models was compared. The model built with the five characteristic waveslengths extected by SPA method only used the variables 0.32% of all the variables in the full wave band, but its accuracy and precision were better than the model built with the full wave band. It is feasible to build a model for different concentrations of chlorpyrifos on fresh winter jujube surfarce by NIR technology combined with SPA and PLS, and SPA method could simplify the complexity of the model and improve the precision and stablity of the model. 展开更多
关键词 Near infrared spectroscopy Pesticide residue SPA Winter jujube PLS
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Regulation of Queue Length in Router Based on an Optimal Scheme
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作者 nannan zhang 《International Journal of Communications, Network and System Sciences》 2009年第5期371-377,共7页
Based on the proportionally fair scheme that Kelly proposed to solve the optimization problems for utility function in networks, and in order to improve the congestion control performance for the queue in router, the ... Based on the proportionally fair scheme that Kelly proposed to solve the optimization problems for utility function in networks, and in order to improve the congestion control performance for the queue in router, the linear and terminal sliding active queue management (AQM) algorithms are designed. Especially in the ter-minal sliding AQM algorithm, a special nonlinear terminal sliding surface is designed in order to force queue length to reach the desired value in finite time. The upper bound of the time is also obtained. Simulation re-sults demonstrate that the proposed congestion algorithm enables the system be better transient and stable performance. At the same time, the robustness is guaranteed. 展开更多
关键词 CONGESTION CONTROL Sliding Mode CONTROL (SMC) Active QUEUE Management (AQM) Kelly’s Proportional FAIR Scheme
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Analysis and Countermeasures on Jilin Physical graduates' Internal Education Causes of employment difficulties
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作者 nannan zhang 《International Journal of Technology Management》 2013年第9期110-112,共3页
The main contents of this paper is a new trend of employment status and employment difficulties of professional sports graduates in Jilin, and analysis on Jilin Physical graduates' Internal Education Causes of employ... The main contents of this paper is a new trend of employment status and employment difficulties of professional sports graduates in Jilin, and analysis on Jilin Physical graduates' Internal Education Causes of employment difficulties ,and how to effectively promote employment of Jilin education and sports undergraduate and graduate and implement measures. In this paper, we use literature, interview survey method, to analyze five professional employment situations of the graduates (physical education major, professional sports training, human movement science, and social sports professional, traditional sports professional). From this perspective of the internal education, employment difficulties of professional sports graduates are these : the concept of employment is a direct factor behind their employment difficulties ; university entrepreneurship education are indirect factors behind Kyrgyzstan employment difficulties ; training model obsolete is the root cause of their difficulties in finding jobs; college enrollment in recent years is its employment difficulties catalyst. This article analyzes the employment situation relating to education, and proposed employment countenueasures which professional sports graduates adapt to, namely: to meet market demand, improve professional structural adjustment; establish the concept of occupation after the first job; establish their own businesses and Multiple Employment Awareness; create a "multi-skilltype" physical training model. 展开更多
关键词 GRADUATES employment difficulties internal education cause analysis COUNTERMEASURES
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Study on the Influence of Blade Outlet Backsweep Angle on Performance of Impeller
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作者 Peng Jiang Yong Tian +1 位作者 Bo Wang nannan zhang 《Open Journal of Applied Sciences》 2022年第4期555-573,共19页
As an important parameter of compressor impeller, the design value of blade outlet backsweep angle has a great influence on the performance of impeller. In this paper, six impellers with blade outlet backsweep angle ... As an important parameter of compressor impeller, the design value of blade outlet backsweep angle has a great influence on the performance of impeller. In this paper, six impellers with blade outlet backsweep angle β<sub>2B</sub> equal to 0°, 10°, 20°, 30°, 40°, and 50° were designed to evaluate the influences of impeller backsweep angle β<sub>2B</sub> on the performance, characteristics of gas flow and equivalent stress using computational fluid dynamics (CFD) and finite element analysis (FEA). Results indicated that the performance curve for the outlet backsweep blade angle β<sub>2B</sub> of 50° has the largest stable operating range. The isentropic efficiency of the impeller with backsweep angle β<sub>2B</sub> equal to 40° is 16.8% - 25.9% higher than that of the impeller with backsweep angle β<sub>2B</sub> equal to 0°. When the blade outlet backsweep angle is 30°, the equivalent stress distribution of the impeller is more uniform, the maximum equivalent stress is the smallest. 展开更多
关键词 IMPELLER Blade Outlet Backsweep Angle PERFORMANCE Isentropic Efficiency CFD Secondary Flow
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All-solid Light-driven Charging and Storage Textile for Wearable Applications
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作者 Xing Fan nannan zhang +1 位作者 Yi Huang Li Cheng 《功能材料信息》 2016年第2期45-45,共1页
Developments in wearable electronics,have brought a revolution to our way of life.In order to power them sustainably and flexibly,novel technologies have been developed to harvesting commonly existed clean and renewab... Developments in wearable electronics,have brought a revolution to our way of life.In order to power them sustainably and flexibly,novel technologies have been developed to harvesting commonly existed clean and renewable energy,such as solar irradiance,wind,rain.Herein,we have come up with the idea of wire-shaped solar cell,which has provided a new solution to get rid of expensive TCO substrates.Progresses have 展开更多
关键词 英语 阅读 理解 纳米材料与技术
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The development of local ambient air quality standards: A case study of Hainan Province, China 被引量:1
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作者 Qian Song nannan zhang +19 位作者 Yanning zhang Dejia Yin Jiming Hao Shuxiao Wang Shengyue Li Wenshuai Xu Weijun Yan Xinxin Meng Xinghong Xu Xiaochen Wu Donghai Xie Yun Zhu Qipeng Qu Xuan Hou Yueqi Jiang Zhaoxin Dong Haotian Zheng Yisheng Sun Zeqi Li Bin Zhao 《Eco-Environment & Health》 2024年第1期11-20,共10页
The ambient air quality standard(AAQS)is a vital policy instrument for protecting the environment and human health.Hainan Province is at the forefront of China's efforts to protect its ecological environment,with ... The ambient air quality standard(AAQS)is a vital policy instrument for protecting the environment and human health.Hainan Province is at the forefront of China's efforts to protect its ecological environment,with an official goal to achieve world-leading air quality by 2035.However,neither the national AAQS nor the World Health Organization guideline offers sufficient guidance for improving air quality in Hainan because Hainan has well met the former while the latter is excessively stringent.Consequently,the establishment of Hainan's local AAQS becomes imperative.Nonetheless,research regarding the development of local AAQS is scarce,especially in comparatively more polluted countries such as China.The relatively high background values and significant interannual fluctuations in air pollutant concentrations in Hainan present challenges in the development of local AAQS.Our research proposes a world-class local AAQS of Hainan Province by reviewing the AAQS in major countries or regions worldwide,analyzing the influence of different statistical forms,and carefully evaluating the attainability of the standard.In the proposed AAQS,the annual mean concentration limit for PM2.5,the annual 95th percentile of daily maximum 8-h mean(MDA8)concentration limit for O_(3),and the peak season concentration limit for O_(3) are set at 10,120,and 85μg/m^(3),respectively.Our study indicates that,with effective control policies,Hainan is projected to achieve compliance with the new standard by 2035.The implementation of the local AAQS is estimated to avoid 1,526(1,253–1,789)and 259(132–501)premature deaths attributable to longterm exposure to PM2.5 and O_(3) in Hainan in 2035,respectively. 展开更多
关键词 Local ambient air quality standard Statistical form FEASIBILITY Health effects Hainan province
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Characteristics of gut microbiota determine effects of specific probiotics strains in patients with functional constipation
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作者 Haohao zhang Lijuan Sun +16 位作者 Zhixin Zhao Yao Zhou Yuyao Liu nannan zhang Junya Yan Shibo Wang Renlong Li Jing zhang Xueying Wang Wenjiao Li Yan Pan Meixia Wang Bing Luo Mengbin Li Zhihong Sun Yongxiang Zhao Yongzhan Nie 《Chinese Medical Journal》 SCIE CAS CSCD 2024年第1期120-122,共3页
To the Editor:Probiotics are a promising treatment modality for functional constipation(FC);however,the factors affecting individual responses to probiotics remain unclear.Growing evidence has identified that there is... To the Editor:Probiotics are a promising treatment modality for functional constipation(FC);however,the factors affecting individual responses to probiotics remain unclear.Growing evidence has identified that there is a strong relationship among the gut microbiota and constipation and related gut-brain axis.[1]The gut microbiota may modulate the gut functions via gut metabolites or trigger the release of gut hormones,such as peptide YY,gastric inhibitory polypeptide,and 5-hydroxytryptamine.[2]In turn,gut hormones affect gut secretion,motility,and sensation through their receptors located on epithelial,enteric,and smooth muscle cells.[2]Based on these findings,exogenous probiotics have been used in patients with constipation;however,few have produced consistent results.[3]In this study,we investigated the efficacy and safety of several specific probiotics strains for constipation,and also examined the potential reasons for the individualized effects of probiotics,which may facilitate interventional decisionmaking for FC patients. 展开更多
关键词 CONSTIPATION PATIENTS SENSATION
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第500例--双髋关节疼痛、头痛、复视
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作者 张楠楠 段彦龙 +7 位作者 王卉 张宁宁 杨菁 张梦 李楠 黄爽 张楠 金玲 《中华内科杂志》 CAS CSCD 北大核心 2023年第2期232-236,共5页
患儿男,5岁3个月,主因双髋关节疼痛40 d,间断头痛、复视24 d就诊。查体无明确阳性体征,神经系统未见明显异常。影像学仅有颅脑及脊髓的异常。脑脊液(CSF)常规:白细胞总数升高,以单个核细胞为主。生化检查:糖及氯化物正常,蛋白增高。考... 患儿男,5岁3个月,主因双髋关节疼痛40 d,间断头痛、复视24 d就诊。查体无明确阳性体征,神经系统未见明显异常。影像学仅有颅脑及脊髓的异常。脑脊液(CSF)常规:白细胞总数升高,以单个核细胞为主。生化检查:糖及氯化物正常,蛋白增高。考虑中枢神经系统感染可能,予抗细菌、抗病毒治疗效果欠佳。进一步完善CSF免疫分型示成熟B细胞淋巴瘤表型,全身其他部位未见肿瘤浸润,最终诊断为原发中枢神经系统淋巴瘤(PCNSL)。按CNCL-2017-成熟B细胞淋巴瘤方案化疗后达到完全缓解,现已完成全部化疗,处于持续完全缓解状态,仍在随访中。临床医生应提高对儿童PCNSL的认识与重视。 展开更多
关键词 儿童 淋巴瘤 诊断 治疗
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Effects of direct aging treatment on microstructure,mechanical properties and residual stress of selective laser melted AlSi10Mg alloy 被引量:4
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作者 Huaping Tang Chaofeng Gao +5 位作者 Yong zhang nannan zhang Chuan Lei Yunjie Bi Ping Tang Jeremy Heng Rao 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2023年第8期198-209,共12页
Direct aging treatment is an important post-processing procedure,yet little research has been done on how it balances the mechanical properties and the stress removal for selective laser melted(SLMed)AlSi10Mg alloys.H... Direct aging treatment is an important post-processing procedure,yet little research has been done on how it balances the mechanical properties and the stress removal for selective laser melted(SLMed)AlSi10Mg alloys.Here,we proposed a typical direct aging treatment on SLMed AlSi10Mg alloys,and studied the effects on their microstructure,properties and residual stress evolution.The results indi-cate that the as-built microstructure is mainly composed of fine cellularα-Al and reticulated Si phases,and some pre-existing precipitates and dislocations are found in these cells.The direct aging treatment promotes the precipitation of nano-scaled Si phases and preserves a network-like Si structure.Therefore,the strength of the peak-aged alloy increases while the ductility decreases.As the aging temperature in-creases from 160 to 200℃,aging hardening behavior was accelerated significantly.Aging at 160℃ for 4-9 h removes 32.0%-43.0%of the residual stress,which is attributed to the decomposition of the su-persaturatedα-Al matrix,the precipitation of the nano-Si phase and the exposure of low-angle grain boundaries(LAGBs).Considering the overal alloy performance obtained,over-aging at 160℃ for 4 h is the optimized heat treatment regime.Under this condition,the yield strength(YS),ultimate tensile strength(UTS)and elongation(EL)of the alloy in the transverse and longitudinal direction are 309.5 MPa,464.4 MPa and 8.3%and 286.4 MPa,464.9 MPa and 5.1%,respectively. 展开更多
关键词 Selective laser melting AlSi10Mg alloys Direct aging treatment Residual stress removal
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