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The Reconnaissance of Mineral Resources through ASTER Data-Based Image Processing, Interpreting and Ground Inspection in the Jiafushaersu Area, West Junggar, China 被引量:7
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作者 Lei Liu jun zhou +2 位作者 Fang Yin Min Feng Bing Zhang 《Journal of Earth Science》 SCIE CAS CSCD 2014年第2期397-406,共10页
Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) data covering the Jiafushaersu area in Xinjiang were used for mapping lithology and hydrothermal alteration. The study area situates at a potent... Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) data covering the Jiafushaersu area in Xinjiang were used for mapping lithology and hydrothermal alteration. The study area situates at a potential mineralization zone in relation to small hypabyssai granodiorite or quartz monzonite intrusions along the margin of granitoid batholiths of Darbut foot wall. The false colour composition of bands 521 and the first three principal component analyses (PCA1, PCA2, PCA3) in RGB identify the lithological units and discriminate the small intrusions very well from the adjacent granitoid batholiths. PCA and spectral angle mapper (SAM) algorithm were employed to discriminate alteration minerals. The results indicate that the hydroxyl-bearing or ferric and less commonly carbonate types show good correlation with the quartz monzonite porphyry and aplite. Field verification led to finding of the Jiafushaersu molybdenum mineralization. The lithological and geochemical features imply that the molybdenum mineralization is close to the porphyry type. This study further verified that the foot wall of the Darbut suture could have served as a more important metallogenic district for the porphyry copper and molybdenum deposits. It is concluded that the ASTER data-based methods can be used as a powerful tool for small intrusion-type mineral resources targeting. 展开更多
关键词 ASTER DARBUT false colour combination principal component analysis SAM.
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Phylogeography and Cryptic Species Diversity of Paramesotriton caudopunctatus Species Group(Salamandridae: Paramesotriton) in Guizhou, China 被引量:2
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作者 Tao LUO Huamei WEN +2 位作者 Kai GAO jun zhou Jiang zhou 《Asian Herpetological Research》 SCIE CSCD 2021年第2期188-200,共13页
The Paramesotriton caudopunctatus species group is mainly distributed in the karst mountain ecosystems of Guizhou, China. Although some species have been included in previous phylogenetic studies, the evolutionary rel... The Paramesotriton caudopunctatus species group is mainly distributed in the karst mountain ecosystems of Guizhou, China. Although some species have been included in previous phylogenetic studies, the evolutionary relationships and divergence-time of members of this species group as a whole remain unexplored. In this study, we report the sequencing of one protein coding mitochondrial gene fragment(ND2) and one nuclear gene(POMC), and use a combination of phylogenetic analyses and coalescent simulations to explore the cryptic diversity and evolutionary history of the P. caudopunctatus species group. Phylogenetic relationships revealed that the P. caudopunctatus species group is composed of two major groups, i. e., East Clade and Western-South Clade. The divergence-time and ancestral area estimation suggested that the P. caudopunctatus species group likely originated in the Doupeng Mountains in Guizhou, China at 12.34 Ma(95% HPD: 8.30–14.73), and intraspecific divergence began at about 2.17 Ma(95% HPD: 1.39–2.97). This timing coincides with the orogenesis of the Miaoling Mountains during the Late Miocene to early Pleistocene. The delimitation of species in the P. caudopunctatus species group supports the existence of the currently identified species, and consensus was confirmed across methods for the existence of least to two cryptic species within what has been traditionally considered to be P. caudopunctatus species group. This study is of significance for understanding the species formation, dispersal, and diversity of the tailed amphibians in the karst mountains ecosystem of Guizhou and the role of the Miaoling Mountains as a geographical barrier to species dispersal. 展开更多
关键词 P.caudopunctatus species group PHYLOGEOGRAPHY cryptic diversity BIOGEOGRAPHY species delimitation GUIZHOU
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The tumor suppressor CYLD controls epithelial morphogenesis and homeostasis by regulating mitotic spindle behavior and adherens junction assembly 被引量:1
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作者 Wei Xie Yunfan Yang +5 位作者 Siqi Gao Ting Song Yuhan Wu Dengwen Li Min Liu jun zhou 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2017年第7期343-353,共11页
Epithelial morphogenesis and homeostasis are essential for animal development and tissue regeneration, and epithelial disorganization is associated with developmental disorders and tumorigenesis. However, the molecula... Epithelial morphogenesis and homeostasis are essential for animal development and tissue regeneration, and epithelial disorganization is associated with developmental disorders and tumorigenesis. However, the molecular mechanisms that contribute to the morphogenesis and homeostasis of the epithelium remain elusive. Herein, we report a novel role for the cylindromatosis (CYLD) tumor suppressor in these events. Our results show that CYLD depletion disrupts epithelial organization in both Drosophila egg chambers and mouse skin and intestinal epithelia. Microscopic analysis of proliferating cells in mouse epithelial tissues and cultured organoids reveals that loss of CYLD synergizes with tumor-promoting agents to cause the misorientation of the mitotic spindle. Mechanistic studies show that CYLD accu- mulates at the cell cortex in epithelial tissues and cultured ceils, where it promotes the formation of epithelial adherens junctions through the modulation of microtuhule dynamics. These data suggest that CYLD controls epithelial morphogenesis and homeostasis by modulating the assembly of adherens junctions and ensuring proper orientation of the mitotic spindle. Our findings thus provide novel insight into the role of CYLD in development, tissue homeostasis, and tumorigenesis. 展开更多
关键词 EPITHELIUM CYLD Mitotic spindle Cell cortex Adherens junction
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A NEW CYCLOPEPTIDE FROM ARENARIA JUNCEA 被引量:2
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作者 Yu Rui ZHAO jun zhou +3 位作者 Xian Kai WANG Xiao Lin HUANG Hou Ming WU Tong Fang ZHAO(Department of Medicinal Chemistry of Natural Products, School of Pharmacy, West China University of Medical Sciences. Chengdu, 610041)(Laboratory of Phytochemistry, Kunming I 《Chinese Chemical Letters》 SCIE CAS CSCD 1994年第9期751-754,共4页
A new cyclopeptide named arenarin A(1) was obtained from the roots of Arenaria juncea Bieb and its structure was established to be cyclo(Ser-Ser-Phe-lle-Pro-Phe)by a combination of 2D-NMR and FABMS.
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Feasibility Study of Enforcing Immunization Certificate Check Before Primary School or Kindergarten Enrollment in Guizhou Province, China
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作者 LI SHENG SHU-YAN ZUO +8 位作者 JING XIE YA-LI QI YI-BING TONG GUANG-PENG TANG jun zhou DA-YONG ZHANG CHANG-BING LONG WEN DU ZI-JIAN FENG 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2007年第5期357-365,共9页
Objective To study the feasibility of enforcing immunization certificate check before children enroll in primary schools or kindergartens in Guizhou Province. Methods Quantitative and qualitative studies were conducte... Objective To study the feasibility of enforcing immunization certificate check before children enroll in primary schools or kindergartens in Guizhou Province. Methods Quantitative and qualitative studies were conducted. The multi-stage and cluster sampling approach was adopted for the quantitative part of the study. A questionnaire was designed and 996 children and their keepers were interviewed. Principals, doctors or teachers of the primary schools, directors and child care nurses of kindergarten, and staff of immunization agencies were invited to take part in 12 focus group discussions; meanwhile, face-to-face individual in-depth interviews with 16 officials of the Health, Education and Governmental Departments at various levels were conducted. Results The total number of subjects was 996. 16.7% of the children in the study completed all the procedures of the National Immunization Programme. 34.3% of them had immunization certificates while the remainder 44.7% registered in immunization agencies. Factors, including the migrant children, doubt about vaccine efficiency, mother’s occupation and educational background, knowledge of the National Immunization Programme on targeted vaccines, played an important role in obtaining or not immunization certificates. 95% of the keepers interviewed thought the immunization certificates were useful; 94.8% of them considered the check was critical while only 3.6% of them thought it unnecessary. The first reason from those who found it unnecessary was that they feared that repeated immunization might affect their children’s health. The second reason was the cost of immunization, which some of them could not afford to pay. However, the Health Department expressed a favorable attitude to the checking scheme. Though the Education Department agreed that the scheme was essential, they worried that it would affect the enrollment rate.Conclusion In spite of the difficulty in administering immunization certificate check, the effort would be rewarding for raising the immunization coverage rate among the children in Guizhou Province. 展开更多
关键词 Immunization certificate check Impacting factors Sampling research Quantitative study Qualitative study Enrollment rate
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Field Prevention and Control of Tobacco Black Shank in Guizhou Province
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作者 Yingjie JIANG Yongmo LI +2 位作者 jun zhou Laifu LUO Yinsheng WANG 《Plant Diseases and Pests》 2024年第5期11-14,23,共5页
[Objectives]The paper was to explore the prevention and therapeutic schedule of tobacco black shank.[Methods]Different concentrations of 25 g/L fludioxonil·37.5 g/L metalaxyl-M,10 billion/mL Bacillus amyloliquefa... [Objectives]The paper was to explore the prevention and therapeutic schedule of tobacco black shank.[Methods]Different concentrations of 25 g/L fludioxonil·37.5 g/L metalaxyl-M,10 billion/mL Bacillus amyloliquefaciens,110 g/L amino acids·24 g/L manganese zinc,120 g/L calcium·20 g/L magnesium,and 4%metalaxyl-M·64%mancozeb were employed to assess their efficacy in controlling tobacco black shank.The disease index was subsequently evaluated.[Results]25 g/L fludioxonil·37.5 g/L metalaxyl-M+10 billion/mL B.amyloliquefaciens+110 g/L amino acids·24 g/L manganese zinc(transplanting dosage)or 120 g/L calcium·20 g/L magnesium(sealing dosage)(transplanting dosage:750 mL/hm^(2)+1.2×10^(4) mL/hm^(2)+1.5×10^(3) mL/hm^(2),sealing dosage:1.5×10^(3) mL/hm^(2)+1.2×10^(4) mL/hm^(2)+1.5×10^(3) mL/hm^(2))resulted in a notable impact on the prevention of tobacco black shank.The incidence in the treated area was 10.78%,a 35.72%reduction compared to the control.The estimated yield was 99700 yuan/hm^(2),a 34.91%increase compared to the control.25 g/L fludioxonil·37.5 g/L metalaxyl-M+10 billion/mL B.amyloliquefaciens+120 g/L calcium·20 g/L magnesium+4%metalaxyl-M·64%mancozeb(control dosage:1.5×10^(3) mL/hm^(2)+1.2×10^(4) mL/hm^(2)+1.5×10^(3) mL/hm^(2)+1.5×10^(3) g/hm^(2),1.5×10^(3) mL/hm^(2)+1.2×10^(4) mL/hm^(2)+1.5×10^(3) mL/hm^(2)+1.5×10^(3) g/hm^(2),with an interval of 7 d between applications)demonstrated a significant efficacy in controlling tobacco black shank.At 7 d following the second application,the relative preventive efficacy was observed to be 88.99%.Additionally,the estimated yield was 109900 yuan/hm^(2),representing an increase of 244.51%compared to the control.[Conclusions]During the transplanting and sealing stages,25 g/L fludioxonil·37.5 g/L metalaxyl-M+10 billion/mL B.amyloliquefaciens+110 g/L amino acids·24 g/L manganese zinc(transplanting dosage)or 120 g/L calcium·20 g/L magnesium(sealing dosage)may be employed to enhance the growth of tobacco plants and mitigate the occurrence of tobacco black shank.Additionally,25 g/L fludioxonil·37.5 g/L metalaxyl-M+10 billion/mL B.amyloliquefaciens+120 g/L calcium·20 g/L magnesium+4%metalaxyl-M·64%mancozeb can be utilized for the treatment of tobacco black shank during the initial incidence stage. 展开更多
关键词 Tobacco black shank PREVENTION TREATMENT FIELD
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An integrated method of data-driven and mechanism models for formation evaluation with logs 被引量:1
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作者 Meng-Lu Kang jun zhou +4 位作者 Juan Zhang Li-Zhi Xiao Guang-Zhi Liao Rong-Bo Shao Gang Luo 《Petroleum Science》 2025年第3期1110-1124,共15页
We propose an integrated method of data-driven and mechanism models for well logging formation evaluation,explicitly focusing on predicting reservoir parameters,such as porosity and water saturation.Accurately interpr... We propose an integrated method of data-driven and mechanism models for well logging formation evaluation,explicitly focusing on predicting reservoir parameters,such as porosity and water saturation.Accurately interpreting these parameters is crucial for effectively exploring and developing oil and gas.However,with the increasing complexity of geological conditions in this industry,there is a growing demand for improved accuracy in reservoir parameter prediction,leading to higher costs associated with manual interpretation.The conventional logging interpretation methods rely on empirical relationships between logging data and reservoir parameters,which suffer from low interpretation efficiency,intense subjectivity,and suitability for ideal conditions.The application of artificial intelligence in the interpretation of logging data provides a new solution to the problems existing in traditional methods.It is expected to improve the accuracy and efficiency of the interpretation.If large and high-quality datasets exist,data-driven models can reveal relationships of arbitrary complexity.Nevertheless,constructing sufficiently large logging datasets with reliable labels remains challenging,making it difficult to apply data-driven models effectively in logging data interpretation.Furthermore,data-driven models often act as“black boxes”without explaining their predictions or ensuring compliance with primary physical constraints.This paper proposes a machine learning method with strong physical constraints by integrating mechanism and data-driven models.Prior knowledge of logging data interpretation is embedded into machine learning regarding network structure,loss function,and optimization algorithm.We employ the Physically Informed Auto-Encoder(PIAE)to predict porosity and water saturation,which can be trained without labeled reservoir parameters using self-supervised learning techniques.This approach effectively achieves automated interpretation and facilitates generalization across diverse datasets. 展开更多
关键词 Well log Reservoir evaluation Label scarcity Mechanism model Data-driven model Physically informed model Self-supervised learning Machine learning
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Single-nucleotide polymorphisms and copy number variations drive adaptive evolution to freezing stress in a subtropical evergreen broadleaved tree:Hexaploid wild Camellia oleifera 被引量:1
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作者 Haoxing Xie Kaifeng Xing +3 位作者 jun zhou Yao Zhao Jian Zhang jun Rong 《Plant Diversity》 2025年第2期214-228,共15页
Subtropical evergreen broad-leaved trees are usually vulnerable to freezing stress,while hexaploid wild Camellia oleifera shows strong freezing tolerance.As a valuable genetic resource of woody oil crop C.oleifera,wil... Subtropical evergreen broad-leaved trees are usually vulnerable to freezing stress,while hexaploid wild Camellia oleifera shows strong freezing tolerance.As a valuable genetic resource of woody oil crop C.oleifera,wild C.oleifera can serve as a case for studying the molecular bases of adaptive evolution to freezing stress.Here,47 wild C.oleifera from 11 natural distribution sites in China and 4 relative species of C.oleifera were selected for genome sequencing.“Min Temperature of Coldest Month”(BIO6)had the highest comprehensive contribution to wild C.oleifera distribution.The population genetic structure of wild C.oleifera could be divided into two groups:in cold winter(BIO6≤0℃)and warm winter(BIO6>0℃)areas.Wild C.oleifera in cold winter areas might have experienced stronger selection pressures and population bottlenecks with lower N_(e) than those in warm winter areas.155 singlenucleotide polymorphisms(SNPs)were significantly correlated with the key bioclimatic variables(106 SNPs significantly correlated with BIO6).Twenty key SNPs and 15 key copy number variation regions(CNVRs)were found with genotype differentiation>50%between the two groups of wild C.oleifera.Key SNPs in cis-regulatory elements might affect the expression of key genes associated with freezing tolerance,and they were also found within a CNVR suggesting interactions between them.Some key CNVRs in the exon regions were closely related to the differentially expressed genes under freezing stress.The findings suggest that rich SNPs and CNVRs in polyploid trees may contribute to the adaptive evolution to freezing stress. 展开更多
关键词 Adaptive evolution Camellia oleifera Copy number variations Freezing stress POLYPLOID Single-nucleotide polymorphisms
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Plasma metabolomics combined with mass spectrometry imaging reveals crosstalk between tumor and plasma in gastric cancer genesis and metastasis 被引量:1
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作者 Yanhua Chen Xian Ding +9 位作者 jun zhou Zhaoying Wang Yunhai Bo Ying Hu Qingce Zang Jing Xu Ruiping Zhang Jiuming He Fen Yang Zeper Abliz 《Chinese Chemical Letters》 2025年第1期506-512,共7页
Gastric Carcinoma(GC)is a highly fatal malignant tumor with a poor prognosis.Its elevated mortality rates are primarily due to its proclivity for late-stage metastasis.Exploring the metabolic interactions between tumo... Gastric Carcinoma(GC)is a highly fatal malignant tumor with a poor prognosis.Its elevated mortality rates are primarily due to its proclivity for late-stage metastasis.Exploring the metabolic interactions between tumor microenvironment and the systemic bloodstream could help to clearly understand the mechanisms and identify precise biomarkers of tumor growth,proliferation,and metastasis.In this study,an integrative approach that combines plasma metabolomics with mass spectrometry imaging of tumor tissue was developed to investigate the global metabolic landscape of GC tumorigenesis and metastasis.The results showed that the oxidized glutathione to glutathione ratio(GSSH/GSH)became increased in non-distal metastatic GC(M0),which means an accumulation of oxidative stress in tumor tissues.Furthermore,it was found that the peroxidation of polyunsaturated fatty acids,such as 9,10-EpOMe,9-HOTrE,etc.,were accelerated in both plasma and tumor tissues of distal metastatic GC(M1).These changes were further confirmed the potential effect of CYP2E1 and GGT1 in metastatic potential of GC by mass spectrometry imaging(MSI)and immunohistochemistry(IHC).Collectively,our findings reveal the integrated multidimensional metabolomics approach is a clinical useful method to unravel the bloodtumor metabolic crosstalk,illuminate reprogrammed metabolic networks,and provide reliable circulating biomarkers. 展开更多
关键词 Metabolomics Spatial-resolved metabolomics Gastric cancer Blood-tumor metabolic crosstalk Lipid peroxidation
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屈光参差性弱视与斜视性弱视的电生理研究 被引量:10
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作者 吴晓璇 周珺 +3 位作者 王肖 高敬 刘瑞芬 赵琪 《中国现代医学杂志》 CAS 北大核心 2017年第28期96-101,共6页
目的分析屈光参差性弱视和斜视性弱视的视觉诱发电位(VEP)与对比敏感度(CS)的特征性变化,并探讨2种弱视不同的致病机制。方法采用德国罗兰公司RETI scan 3.15系统对20例屈光参差性弱视、9例斜视性弱视和18例非弱视性儿童的双眼行VEP和C... 目的分析屈光参差性弱视和斜视性弱视的视觉诱发电位(VEP)与对比敏感度(CS)的特征性变化,并探讨2种弱视不同的致病机制。方法采用德国罗兰公司RETI scan 3.15系统对20例屈光参差性弱视、9例斜视性弱视和18例非弱视性儿童的双眼行VEP和CS检查,进行弱视眼、对侧眼及非弱视眼之间的对比研究。结果与对侧眼或非弱视眼相比,屈光参差性弱视眼在高空间频率条件下潜时延长,而斜视性弱视眼在全空间频率条件下潜时延长。2种弱视眼的振幅在低频时均下降。屈光参差性弱视对侧眼与非弱视眼比较差异无统计学意义(P>0.05),而斜视性弱视对侧眼的潜时在低频下较非弱视眼延长,差异有统计学意义(P<0.05)。屈光参差性弱视眼和对侧眼的CS与非弱视眼比较差异无统计学意义(P>0.05)。斜视性弱视眼表现为全空间频率上的CS下降,差异有统计学意义(P<0.05),其对侧眼的CS则优于非弱视眼。结论本研究结果支持斜视性弱视与屈光参差性弱视拥有不同神经机制的观点。斜视性弱视的对侧眼并非"健眼"。VEP与CS检查对弱视诊断具有临床意义。 展开更多
关键词 屈光参差性弱视 斜视性弱视 视觉诱发电位 对比敏感度
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透明质酸对膝关节骨性关节炎相关细胞因子及生物标志物的影响 被引量:17
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作者 廖瑛 张兴 +5 位作者 周君 曾亚华 成果 王甜甜 邓程远 黎洲 《中国现代医学杂志》 CAS 2019年第4期33-38,共6页
骨性关节炎(OA)是一种由不同病因引起的综合征最终聚集在同一致病途径上,产生软骨、软骨下骨和滑膜的特征性变化。OA由于软骨破坏及其代谢改变,可在其体液中寻找反映软骨结构变化的相关细胞因子和特异性生物标志物,这对于OA的诊疗及预... 骨性关节炎(OA)是一种由不同病因引起的综合征最终聚集在同一致病途径上,产生软骨、软骨下骨和滑膜的特征性变化。OA由于软骨破坏及其代谢改变,可在其体液中寻找反映软骨结构变化的相关细胞因子和特异性生物标志物,这对于OA的诊疗及预后评估起到积极的指导作用。关节腔注射透明质酸(HA)是治疗膝关节OA最常用的有效方法,其可刺激内生HA分泌,润滑关节组织,也可有效防止软骨降解。此外,关节腔注射HA可以降低金属蛋白酶含量,减少促炎介质的产生,从而减少参与OA发病机制的因素,改善关节炎症症状和关节软骨的损伤。 展开更多
关键词 骨关节炎 透明质酸 细胞因子类
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SATB1、CBX7表达预测结直肠癌患者术后复发的价值 被引量:7
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作者 马博 周军 +1 位作者 李建刚 王俊 《中国现代医学杂志》 CAS 北大核心 2022年第20期90-95,共6页
目的探究核基质结合区结合蛋白1(SATB1)与色素框蛋白7(CBX7)表达预测结直肠癌患者术后复发的价值。方法回顾性分析2018年4月—2021年2月新疆医科大学第二附属医院收治的104例行结直肠癌根治术患者的临床资料,取其留存的癌组织蜡块进行... 目的探究核基质结合区结合蛋白1(SATB1)与色素框蛋白7(CBX7)表达预测结直肠癌患者术后复发的价值。方法回顾性分析2018年4月—2021年2月新疆医科大学第二附属医院收治的104例行结直肠癌根治术患者的临床资料,取其留存的癌组织蜡块进行分析。采用免疫组织化学法检测癌组织SATB1、CBX7的表达,两组患者均随访12个月,按照术后复发、淋巴结远端转移将患者分为复发组和未复发组。采用多因素Logistic回归模型分析结直肠癌术后复发的相关因素。绘制受试者工作特征(ROC)曲线评估SATB1、CBX7表达预测结直肠癌术后复发的价值。结果104例结直肠癌患者中73例复发,复发率为70.19%。复发组临床分期Ⅲ和Ⅳ期、肿瘤低分化、有淋巴结转移、SATB1阳性表达、CBX7阳性表达、SATB1和CBX7均阳性表达占比均高于未复发组(P<0.05),SATB1、CBX7均阴性表达占比低于未复发组(P<0.05)。多因素Logistic回归分析结果显示,临床分期Ⅲ和Ⅳ期、肿瘤低分化、淋巴结转移、SATB1阳性表达及CBX7阳性表达均为结直肠癌术后复发的危险因素(P<0.05)。ROC曲线结果显示,SATB1阳性、CBX7阳性、SATB1和CBX7均阳性、SATB1和CBX7均阴性预测结直肠癌术后复发的曲线下面积分别为0.640(95%CI:0.524,0.756)、0.659(95%CI:0.546,0.771)、0.739(95%CI:0.641,0.837)和0.743(95%CI:0.633,0.853)。结论SATB1、CBX7表达预测结直肠癌术后复发效能较高。 展开更多
关键词 结直肠癌 核基质结合区结合蛋白1 色素框蛋白7 术后复发 预测价值
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Phonon Angular Momentum Generation in Single-Stranded Helix Structure
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作者 Hong Sun Jiaqi Chen +3 位作者 Qingxuan Wang Xiaoliang Zeng jun zhou Lifa Zhang 《Chinese Physics Letters》 2025年第9期246-260,共15页
The experimental realization of observable phonon angular momentum(PAM)in feasible systems using relatively simple methods remains a critical challenge.Motivated by the chiral-induced spin selectivity effect,this stud... The experimental realization of observable phonon angular momentum(PAM)in feasible systems using relatively simple methods remains a critical challenge.Motivated by the chiral-induced spin selectivity effect,this study explores the generation of PAM during the transport of electrically driven polarons along a singlestranded helix structure.We demonstrate that the motion of a polaron under an applied electric field inherently induces a finite PAM,exhibiting drift-locked behavior between the PAM and the polaron.By analyzing the time evolution of PAM distribution at each site,we identify the observed PAM as a natural consequence of coherent superposition between lattice waves,in which the chiral structure selectively determines the direction of induced PAM.Furthermore,we examine the roles of two types of electron-phonon interactions and structural periodicity in modulating PAM.These findings highlight the potential of chiral molecules as platforms for PAM generation and offer new insights into developing phonon-spin-based devices for information processing and transmission. 展开更多
关键词 transport electrically driven polarons phonon angular momentum pam electron phonon interactions structural periodicity POLARONS singlestranded helix structurewe phonon angular momentum chiral molecules
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Development and application of a nitrogen oxides analyzer based on the cavity attenuated phase shift technique
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作者 jun zhou Wenjie Wang +5 位作者 Yanfeng Wu Chunsheng Zhang Aiming Liu Yixin Hao Xiao-Bing Li Min Shao 《Journal of Environmental Sciences》 2025年第4期692-703,共12页
Nitrogen oxides(NO_(x))are crucial in tropospheric photochemical ozone(O_(3))production and oxidation capacity.Currently,the widely used NO_(x)measurement technique is chemiluminescence(CL)(CL-NO_(x)),which tends to o... Nitrogen oxides(NO_(x))are crucial in tropospheric photochemical ozone(O_(3))production and oxidation capacity.Currently,the widely used NO_(x)measurement technique is chemiluminescence(CL)(CL-NO_(x)),which tends to overestimate NO_(2)due to atmospheric oxidation products of NO_(x)(i.e.,NO_(z)).We developed and characterized a NO_(x)measurement system using the cavity attenuated phase shift(CAPS)technique(CAPS-NO_(x)),which is free from interferences with nitrogen-containing species.The NO_(x)measured by the CAPS-NO_(x)and CL-NO_(x)analyzers were compared.Results show that both analyzers showed consistent measurement results for NO,but the NO_(2)measured by the CAPS-NO_(x)analyzer(NO_(2)_CAPS)was mostly lower than that measured by the CL-NO_(x)analyzer(NO_(2)_CL),which led to the deviations in O_(3)formation sensitivity regime and O_(x)(=O_(3)+NO_(2))sources(i.e.,regional background and photochemically produced O_(x))determined by the ozone production efficiencies(OPE)calculated from NO_(2)_CL and NO_(2)_CAPS.Overall,OPE_CL exceeded OPE_CAPS by 18.9%,which shifted 3 out of 13 observation days from the VOCs-limited to the transition regime when judging using OPE_CL,as compared to calculations using OPE_CAPS.During the observation period,days dominated by regional background O_(x)accounted for 46%and 62%when determined using NO_(2)_CL and NO_(2)_CAPS,respectively.These findings suggest that the use of the CL-NO_(x)analyzer tends to underestimate both the VOCs-limited regime and the regional background O_(x)dominated days.The newly built CAPS-NO_(x)analyzer here can promote the accurate measurement of NO_(2),which is meaningful for diagnosing O_(3)formation regimes and O_(x)sources. 展开更多
关键词 Nitrogen oxides measurement Cavity attenuated phase shift (CAPS)technique Instrument development O_(3)formation regime O_(x)source
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A novel fluoroapatite-type phosphor Ca_(2)Y_(8)(BO_(4))_(2)(SiO_(4))_(4)F_(2)Eu^(3+) with high quantum efficiency and good thermal stability for multimodal applications
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作者 Zhenyun Wang Tian Tian +7 位作者 Weiwei Wang Yao Cheng Yao Zheng Jiaqi Gao Jiahui Ru Yaoqing Chu jun zhou Jiayue Xu 《Journal of Rare Earths》 2025年第10期2065-2076,I0001,共13页
A novel Eu^(3+)-doped fluorapatite red phosphor Ca_(2)Y_(8)(BO_(4))_(2)(SiO_(4))_(4)F_(2)Eu^(3+)with pure phase was synthesized in this study.Density functional theory(DFT)calculation and diffuse reflection spectrum a... A novel Eu^(3+)-doped fluorapatite red phosphor Ca_(2)Y_(8)(BO_(4))_(2)(SiO_(4))_(4)F_(2)Eu^(3+)with pure phase was synthesized in this study.Density functional theory(DFT)calculation and diffuse reflection spectrum analysis reveal its potential as a matrix for phosphors excited by ultraviolet light.Eu^(3+)has a^(7)F_(0)→^(5)L_(6)transition at 394 nm,and the prepared phosphor exhibits a high emission intensity at 614 nm,which may be attributed to the^(5)D_(0)-^(7)F_(2)energy transition at the lower symmetry site of Eu^(3+).The optimal doping concentration of the phosphor is determined to be 11 mol%,with concentration quenching attributed to the exchange interaction mechanism.The overall color purity of the phosphor is up to 99.88%,with an internal quantum efficiency as high as 91.15%.Notably,Ca_(2)Y_(8)(BO_(4))_(2)(SiO_(4))_(4)F_(2):11 mol%Eu^(3+)(CYBSF:11 mol%Eu^(3+))phosphors exhibit good thermal stability,with a thermal quenching temperature(T1/2)of 552 K and the intensity of emission at 423 K still at 88.89%of that at 298 K.The activation energy of the phosphor is up to 0.30287 eV.Its comprehensive luminescence performance surpasses that of commercial red phosphor,making it suitable for near ultraviolet excited warm white light emitting diode(NUV-WLED)with a high color rendering index(Ra=82)and a correlated color temperature(CCT)of 4339 K.Moreover,the phosphor achieves latent fingerprint visualization and anti-counterfeiting ink on different material surfaces:glass,aluminum foil,plastic and paper.Overall,the fluorapatite CYBSF:11 mol%Eu^(3+)phosphor holds great potential for multimodal applications due to its high quantum efficiency and good thermal stability. 展开更多
关键词 Eu^(3+)-doped Ca_(2)Y_(8)(BO_(4))_(2)(SiO_(4))_(4)F_(2) FLUOROAPATITE High quantum efficiency Thermal stability Multimodal applications Rare earths
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Systematic modeling and methodological approaches for optimizing gas storage facility design with fluctuating hydraulic characteristics
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作者 Shi-Tao Liu Cheng-Yu Li +5 位作者 jun zhou Zi-Chen Li Zhan-Peng Ye Jing-Hong Peng Yun-Xiang Zhao Guang-Chuan Liang 《Petroleum Science》 2025年第6期2546-2569,共24页
As the proportion of natural gas consumption in the energy market gradually increases,optimizing the design of gas storage surface system(GSSS)has become a current research focus.Existing studies on the two independen... As the proportion of natural gas consumption in the energy market gradually increases,optimizing the design of gas storage surface system(GSSS)has become a current research focus.Existing studies on the two independent injection pipeline network(InNET)and production pipeline network(ProNET)for underground natural gas storage(UNGS)are scarce,and no optimization methods have been proposed yet.Therefore,this paper focuses on the flow and pressure boundary characteristics of the GSSS.It constructs systematic models,including the injection multi-condition coupled model(INM model),production multi-condition coupled model(PRM model),injection single condition model(INS model)and production single condition model(PRS model)to optimize the design parameters.Additionally,this paper proposes a hybrid genetic algorithm based on generalized reduced gradient(HGA-GRG)for solving the models.The models and algorithm are applied to a case study with the objective of minimizing the cost of the pipeline network.For the GSSS,nine different condition scenarios are considered,and iterative process analysis and sensitivity analysis of these scenarios are conducted.Moreover,simulation scenarios are set up to verify the applicability of different scenarios to the boundaries.The research results show that the cost of the InNET considering the coupled pressure boundary is 64.4890×10^(4) CNY,and the cost of the ProNET considering coupled flow and pressure boundaries is 87.7655×10^(4) CNY,demonstrating greater applicability and economy than those considering only one or two types of conditions.The algorithms and models proposed in this paper provide an effective means for the design of parameters for GSSS. 展开更多
关键词 Gas storage Pipeline diameter optimization Hybrid genetic algorithm based on generalized reduced gradient Multi-condition Hydraulic characteristics
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Non-linear responses of the plant phosphorus pool and soil available phosphorus to short-term nitrogen addition in an alpine meadow
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作者 Bing Han Yicheng He +7 位作者 jun zhou Yufei Wang Lina Shi Zhenrong Lin Lu Yu Wantong Zhang Yiyi Geng Xinqing Shao 《Journal of Integrative Agriculture》 2025年第3期815-826,共12页
Nitrogen(N)enrichment is expected to induce a greater phosphorus(P)limitation,despite the acceleration of soil P cycling.However,the changing patterns in plant P and soil available P after N enrichment,and their regul... Nitrogen(N)enrichment is expected to induce a greater phosphorus(P)limitation,despite the acceleration of soil P cycling.However,the changing patterns in plant P and soil available P after N enrichment,and their regulatory mechanisms,remain poorly understood in alpine meadows.Here,we conducted a field experiment with four N addition rates(0,5,10,and 15 g N m^(-2)yr^(-1))in an alpine meadow,and investigated the P in plants,microorganisms,and soil to determine their patterns of change after short-term N addition.Our results showed that N addition significantly increased plant biomass,and the plant P pool showed a non-linear response to the N addition gradient.Soil available P initially increased and then declined with increasing N addition,whereas the occluded inorganic P decreased markedly.The critical factors for soil available P varied with different N addition rates.At lower N addition levels(0 and 5 g N m^(-2)yr^(-1)),soil acidification facilitated the mobilization of occluded inorganic P to increase soil available P.Conversely,at higher N addition levels(10 and 15 g N m^(-2)yr^(-1)),the elevated soil microbial biomass P intensified the competition with plants for soil P,leading to a decline in soil available P.This study highlights the nonlinear responses of the plant P pool and soil available P concentration to N addition rates.These responses suggest the need for developing ecosystem models to assess different effects of increasing N rates,which would enable more accurate predictions of the plant P supply and soil P cycling under N enrichment. 展开更多
关键词 nitrogen addition rates Qinghai-Tibetan Plateau unimodal response microbial biomass phosphorus soil phosphorus fractions
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The mechanism for the self-accommodation microstructure ofαvariants during phase transformation of the Zr–2.5Nb alloy
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作者 Guodong Song Conghui Zhang +5 位作者 Yunchang Xin Xinde Huang Peidong Wu jun zhou Wenguang Zhu Xuan zhou 《Journal of Materials Science & Technology》 2025年第21期92-104,共13页
Although variant selection during the phase transformation of zirconium(Zr)alloys has been studied extensively,studies on the formation mechanism of microstructural characteristics related to a variant selection remai... Although variant selection during the phase transformation of zirconium(Zr)alloys has been studied extensively,studies on the formation mechanism of microstructural characteristics related to a variant selection remain limited.The formation mechanisms of the self-accommodation morphology and inter-variant boundary characteristics of a variants in homogenized Zr-2.5Nb alloy cooled by water quenching(WQ),furnace cooling(FC),and air cooling(AC)were systematically investigated from the perspective of local strain during phase transformation.The a variants exhibited triangular morphologies in both the WQ and AC samples,and a colony morphology in the FC sample.Further,there were five types of inter-variant boundaries:TypeI<0001>/10.53°,Typell<1120>/60°,Type Ill<1.377 I 2.3770.359>/60.83°,Type IV<10553>/63.26°,and Type V<12.381.380>/90°.The proportion of Type ll is up to 98%in the AC sample and 57.9%in the WQ sample;the Type I was very low in all three samples;and a high proportion of the Type V was observed in the FC sample(23.6%).The self-accommodation morphology of a variants is closely related to the equivalent strain(Evm)during the variant selection.Theoretical calculations indicated that,for a specific 2-variant combinations,there were always one or more 3-variant combinations with a lower Evm than the 2-variant combinations.A lower eym contributes to the presence of 3-variant combinations,which forms a triangle morphology.The formation of inter-variant boundaries is determined by the type and frequency of variants as well as the eym of the 2-variant combinations.The order of the mean values of evm for the five types of boundaries was Type II(0.0757),Type III(0.0859),Type IV(0.1012),Type V(0.1112),and Type I(0.1307).That is,Type II is the easiest and Type I is the most difficult,which resulted in a very high fraction of Type ll and a very low fraction of Type I in the WQ,AC,and FC samples.The presence of a high fraction of Type V in the FC sample was related to the type and fraction of each variant. 展开更多
关键词 Zirconium alloy Phase transformation Variant selection MICROSTRUCTURE Equivalent strain
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Preliminary Screening of Agents for the Management of Root Rot in Tobacco Floating Seedlings
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作者 Yuzhen CHEN Gui GAO +2 位作者 Wu YANG jun zhou Yingjie JIANG 《Plant Diseases and Pests》 2025年第2期8-12,共5页
[Objectives]To screen effective agents for the management of root rot in tobacco floating seedlings.[Methods]A total of eight treatments were implemented in a large-scale field trial,which included three replications.... [Objectives]To screen effective agents for the management of root rot in tobacco floating seedlings.[Methods]A total of eight treatments were implemented in a large-scale field trial,which included three replications.Each treatment was administered at the recommended dosages.[Results]The application of Metalaxyl-M·Fludioxonil+amino acids demonstrated a control efficacy of 93.65%against root rot in tobacco floating seedlings.In comparison,the application of Metalaxyl-M·Fludioxonil alone exhibited a control efficacy of 88.42%.The most effective treatment for promoting root growth in tobacco seedlings was Metalaxyl-M·Fludioxonil+amino acids,which resulted in a 54.65%increase in root growth compared to the blank control.This was followed by the application of Metalaxyl-M·Fludioxonil alone,which yielded a 39.53%increase in root growth relative to the blank control.[Conclusions]The application of Metalaxyl-M·Fludioxonil+amino acids is recommended for use in the seedling pools of tobacco seedling cultivation.Specifically,it is advised to incorporate 1 mL of Metalaxyl-M·Fludioxonil and 2 mL of amino acids into each seedling tray prior to their introduction into the seedling pool.This treatment has demonstrated significant efficacy in preventing and controlling root rot in tobacco floating seedlings,while also promoting the health of the root system and ensuring the quality of transplanted tobacco seedlings. 展开更多
关键词 TOBACCO SEEDLINGS SEEDBED DISINFECTION FUNGICIDE
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Simultaneous enhancement of tensile strength and electrical conductivity of drawn Cu–20 wt.% Fe wire through intermediate annealing
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作者 Fei Yang Can-hui Wu +7 位作者 Yuan-fang Wang Rui-feng Li Feng-jian Shi Wen-yi Huo Li-ming Dong jun zhou Yan-xin Qiao Feng Fang 《Journal of Iron and Steel Research International》 2025年第10期3410-3425,共16页
The deformation of Cu–20 wt.%Fe alloy wires leads to a significant improvement in mechanical properties and a decrease in electrical conductivity.Simultaneous improvements in strength and conductivity were achieved b... The deformation of Cu–20 wt.%Fe alloy wires leads to a significant improvement in mechanical properties and a decrease in electrical conductivity.Simultaneous improvements in strength and conductivity were achieved by intermediate annealing of drawn Cu–20 wt.%Fe wires.As the annealing temperature increased,the strength of Cu–20 wt.%Fe alloy wire decreased monotonically,but the electrical conductivity first increased and then decreased,reaching its peak value after annealing at 500℃.The decrease in strength is related to dislocation recovery and static recrystallization of Cu and Fe phases,and the increase in electrical conductivity mainly results from the aging precipitation of solid solution Fe.After annealing at 500℃,there was no obvious recrystallization of Cu phase,and many of the nano-Fe particles precipitated from Cu matrix.An annealing temperature of 600℃ induced the recrystallization of Cu matrix and an increase in Fe solid solubility,resulting in a decrease in strength and electrical conductivity.Subsequently,the wires annealed at 500℃ were drawn to 2 mm.Compared with those of the continuously drawn Cu–20 wt.%Fe alloy wires,the deformation ability,strength,and electrical conductivity of Cu–20 wt.%Fe alloy wires subjected to intermediate annealing treatment are significantly greater.This is mainly related to the sufficient precipitation of Fe in Cu matrix and the strengthening of refined Fe fibers parallel to the drawing direction. 展开更多
关键词 Cu-Fe alloy wire Drawing deformation Intermediate annealing Electrical conductivity Mechanical property
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