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取秧侧向零偏移的空间轨迹再生稻分插机构设计与试验

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农业机械学报 2024年第2期55卷 101-108页

作者：孙良姜凯雯周斌俞高红崔荣江薛向磊浙江理工大学机械工程学院杭州310018 浙江省种植装备技术重点实验室杭州310018 杭州职业技术学院杭州310018 浙江省农业科学院杭州310018 农业农村部东南丘陵山地农业装备重点实验室杭州310018

为了解决现有空间行星轮系式分插机构在再生稻宽窄行机械化种植取秧过程中出现侧向偏移量和侧向偏转角的技术难题,本文提出一种具有局部平面轨迹特性的空间轨迹不等速行星轮系机构,并开展基于取秧口和机构回转中心位置约束下的宽窄行分... 详细信息

为了解决现有空间行星轮系式分插机构在再生稻宽窄行机械化种植取秧过程中出现侧向偏移量和侧向偏转角的技术难题,本文提出一种具有局部平面轨迹特性的空间轨迹不等速行星轮系机构,并开展基于取秧口和机构回转中心位置约束下的宽窄行分插机构综合研究。构建了基于关键位姿点(取秧起始点、取秧结束点、推秧点)的空间轮系机构运动综合模型,利用关键位姿点求解机构杆长参数与空间交错轴信息,并通过优选二杆相对角位移参数实现机构传动比分配。将不完全非圆齿轮副引入空间行星轮系机构,利用间歇机构锁止弧约束行星轴,实现机构取秧过程侧向零偏移量、侧向零偏转角的平面轨迹段。通过仿真分析与机构样机试验验证了机构实际作业性能与理论设计相一致,结果表明:分插机构取秧侧向零偏移量,取秧侧向零偏转角,推秧侧向总偏移量为50.24 mm、取秧角为5.18°、推秧角为71.56°、推秧侧向角为16.26°、插秧穴口宽度为22.43 mm、轨迹高度为289.76 mm,满足预期设计要求。最后通过田间试验验证,分插机构可实现等行距取秧口和既定机构回转中心下宽行(40 cm)与窄行(20 cm)间隔机插,满足再生稻宽窄行种植要求。

关键词：再生稻分插机构零偏移量零偏角宽窄行不完全非圆齿轮系

基于多视图自编码器的多被试者脑影像功能校准

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计算机科学 2024年第3期51卷 141-146页

作者：黄硕孙亮汪美玲张道强南京航空航天大学脑机智能技术教育部重点实验室南京211106 南京航空航天大学计算机科学与技术学院南京211106

功能磁共振成像(functional Magnetic Resonance Imaging,fMRI)研究面临的主要挑战之一是不同被试者fMRI数据的异质性。一方面,多被试数据分析对于确定所生成结果跨被试的通用性和有效性至关重要。另一方面,分析多被试者fMRI数据需要在... 详细信息

功能磁共振成像(functional Magnetic Resonance Imaging,fMRI)研究面临的主要挑战之一是不同被试者fMRI数据的异质性。一方面,多被试数据分析对于确定所生成结果跨被试的通用性和有效性至关重要。另一方面,分析多被试者fMRI数据需要在不同被试者的神经活动之间进行准确的解剖和功能校准,以提升最终结果的性能。然而,现有大多数功能校准研究都采用浅层模型来处理多被试者间的复杂关系,这严重束缚了多被试信息的建模能力。为此,提出了一种基于多视图自编码器的功能校准(Multi-view Auto-encoder Functional Alignment,MAFA)方法。具体地,该方法通过重构不同被试者的响应空间来学习节点嵌入,捕获不同被试者之间共享的特征表示,从而创建一个公共的响应空间。此外,通过引入自训练聚类目标,利用高置信度节点作为软标签来监督图聚类过程。在4个数据集上的实验结果表明,相比其他多被试者脑影像功能校准方法,所提方法在解码精度方面取得了最佳效果。

关键词：功能磁共振成像功能校准多视图表示学习多被试分析脑解码

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盐碱地特色中药农业新理念思考与实践

华北理工大学学报（自然科学版） 2024年第1期46卷 1-7页

作者：孙良丹华北理工大学医学部河北唐山063210

对盐碱地综合利用是补充耕地资源不足的主要途径,也是我国粮食安全和区域生态安全的重要战略需求。现今盐碱地综合利用面临盐碱地改良、农田保护、水资源利用、良种培育、生态保护等多方面的挑战,而科技创新是盐碱地绿色开发和高效可持... 详细信息

对盐碱地综合利用是补充耕地资源不足的主要途径,也是我国粮食安全和区域生态安全的重要战略需求。现今盐碱地综合利用面临盐碱地改良、农田保护、水资源利用、良种培育、生态保护等多方面的挑战,而科技创新是盐碱地绿色开发和高效可持续利用的关键。作者从“盐碱地综合利用”和“中医药创新发展”两大国家战略入手,率先提出“盐碱地特色中药农业”新理念,以“盐碱地改良、耐盐碱中药种植、靶向重大炎症免疫疾病的耐盐碱中药有效成分识别与提取、药食同源产品开发”为主形成双向链条式研究模式,通过科技协同创新抢占“盐碱地特色中药农业”制高点,实现盐碱地绿色开发和高效可持续利用。

关键词：盐碱地综合利用中药种植炎症与免疫疾病

基于遥感作物参考曲线的黄土高原苹果产区始花期监测

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遥感技术与应用 2024年第2期39卷 328-336页

作者：王梓霖王钊孙亮孙政段梦琦王永前成都信息工程大学资源与环境学院四川成都610225 陕西省农业遥感与经济作物气象服务中心陕西西安710016 中国农业科学院农业资源与农业区划研究所北京100081

苹果种植业为陕西省提升农业、富裕农民的支柱型产业。黄土高原苹果产区每年都有花期防冻害和产量评估的需求,花期监测尤为重要,而常规的花期监测方法存在监测成本大和精度低的问题。采用一种基于遥感作物参考曲线重建的方法,介绍比较... 详细信息

苹果种植业为陕西省提升农业、富裕农民的支柱型产业。黄土高原苹果产区每年都有花期防冻害和产量评估的需求,花期监测尤为重要,而常规的花期监测方法存在监测成本大和精度低的问题。采用一种基于遥感作物参考曲线重建的方法,介绍比较了该方法与其他方法应用于常见作物的精度,并使用地理国情普查地表覆盖分类数据识别的MODIS纯像元中提取一组NDVI时间序列,将其用于拟合类似Sentinel-2的观测值,将这种方法应用于黄土高原地区苹果作物上,根据苹果样点的归一化植被指数(NDVI)序列(作物参考曲线)与重建后的苹果NDVI序列在空间上的物候差异,绘制历史10 m高分辨率的始花期监测结果,实现了花期监测由点到面的转化。研究结果表明:2019~2021三年验证区域苹果始花期的探测结果平均值与地面数据绝对误差均在1~3 d之内,平均绝对误差为0.926 d,均方根误差为1.503 d。该方法可用于苹果花期高精度监测,预测结果可为实际生产中苹果花期防冻害和产量评估工作的开展提供参考,同时这种方法也可以用于研究其他作物的物候特征,如小麦、玉米等,有望为农业生产提供更准确的决策支持。

关键词：作物参考曲线物候苹果始花期探测遥感黄土高原

Prognostic Significance of Tumor-infiltrating CD8^＋ or CD3^＋ T Lymphocytes and Interleukin-2 Expression in Radically Resected Non-small Cell Lung Cancer

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Chinese Medical Journal 2015年第1期128卷 105-110页

作者： Chuntao Tian Shixin Lu Qingxia Fan Weijie Zhang Shunchang Jiao Xiao Zhao Zhiyong Wu liang sun Liuxing Wang Department of Oncology First Affiliated Hospital Zhengzhou University Zhengzhou Henan 450052 China Department of Etiology and Carcinogenesis Cancer Institute and Hospital Chinese Academy of Medical Sciences Beijing 100021 China Department of Oncology General Hospital of Chinese People's Liberation Army Beijing 100853 China Department of Epidemiology and Statistics College of Public Health Zhengzhou University Zhengzhou Henan 450001 China

Background：Altered immunoresponse is associated with tumorigenesis and cancer progression.This study assessed the levels of tumor-infiltrating CD3^＋ or CD8^＋ T lymphocytes and interleukin-2 （IL-2） protein in radically resected non-small cell lung cancer （NSCLC） tissues to predict overall survival （OS） of the patients.Methods：Paraffin-embedded tissue specimens from 129 NSCLC patients were retrospectively collected for immunostaining of CD8^＋,CD3^＋,and IL-2 expression.Clinicopathological and survival data were collected and analyzed using the Chi-squared test,Kaplan-Meier curves,and the log-rank test or the Cox regression model.Results：The data showed a significant inverse association between CD8^＋ T lymphocyte levels and IL-2 expression （r =-0.927; P =0.000） and between the levels of CD8^＋ and CD3^＋ T lymphocytes （r =-0.722; P =0.000）,but a positive association between CD3^＋ T lymphocyte levels and IL-2 expression （r =0.781; P =0.000） in NSCLC tissues.Furthermore,the levels of CD3^＋ and CD8^＋ T lymphocytes and IL-2 expression were associated with tumor stage （P =0.023,0.006,and 0.031,respectively） and the level of CD8^＋ T lymphocytes was associated with the patient gender （P =0.024）.In addition,the levels of CD8^＋ T lymphocytes were associated with an unfavorable 5-year OS,whereas patients with high levels of CD3^＋ T lymphocytes in tumor lesions and IL-2-expressing tumors had significantly better 5-year OS rates than patients with low levels.Conclusions：The levels of CD8^＋ T cells in tumor lesions and IL-2 expression were both independent predictors of OS for these NSCLC patients.Thus,the detection of tumor-infiltrating CD3^＋ or CD8^＋ T lymphocytes and IL-2 expression could be useful to predict the prognosis of radically resected NSCLC patients.

关键词： Immunohistochemistry Immunological Parameters Non-small Cell Lung Cancer Prognostic Factors

S100A8 promotes epithelial-mesenchymal transition and metastasis under TGF-β/USF2 axis in colorectal cancer

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Cancer Communications 2021年第2期41卷 154-170页

作者： Si Li Jun Zhang Senmi Qian Xuesong Wu liang sun Tianyi Ling Yao Jin Wenxiao Li Lichao sun Maode Lai Fangying Xu Department of Pathology and Pathophysiology and Department of General Surgery of the Second Affiliated HospitalZhejiang University School of MedicineHangzhouZhejiang 310058P.R.China Department of Pathology and Pathophysiology Zhejiang University School of MedicineHangzhouZhejiang 310058P.R.China Key Laboratory of Disease Proteomics of Zhejiang Province Zhejiang University School of MedicineHangzhouZhejiang 310058P.R.China State Key Laboratory of Molecular Oncology National Cancer Center/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021P.R.China

Background:The transforming growth factor-β(TGF-β)pathway plays a pivotal role in inducing epithelial-mesenchymal transition(EMT),which is a key step in cancer invasion and metastasis.However,the regulatory mechanism of TGF-βin inducing EMT in colorectal cancer(CRC)has not been fully elucidated.In previous studies,it was found that S100A8 may regulate EMT.This study aimed to clarify the role of S100A8 in TGF-β-induced EMT and explore the underlying mechanism in CRC.Methods:S100A8 and upstream transcription factor 2(USF2)expression was detected by immunohistochemistry in 412 CRC tissues.Kaplan-Meier survival analysis was performed.In vitro,Western blot,and migration and invasion assays were performed to investigate the effects of S100A8 and USF2 on TGF-β-induced EMT.Mouse metastasis models were used to determine in vivo metastasis ability.Luciferase reporter and chromatin immunoprecipitation assay were used to explore the role of USF2 on S100A8 transcription.Results:During TGF-β-induced EMT in CRC cells,S100A8 and the transcription factor USF2 were upregulated.S100A8 promoted cell migration and invasion and EMT.USF2 transcriptionally regulated S100A8 expression by directly binding to its promoter region.Furthermore,TGF-βenhanced the USF2/S100A8 signaling axis of CRC cells whereas extracellular S100A8 inhibited the USF2/S100A8 axis of CRC cells.S100A8 expression in tumor cells was associated with poor overall survival in CRC.USF2 expression was positively related to S100A8 expression in tumor cells but negatively related to S100A8-positive stromal cells.Conclusions:TGF-βwas found to promote EMT and metastasis through the USF2/S100A8 axis in CRC while extracellular S100A8 suppressed the USF2/S100A8 axis.USF2 was identified as an important switch on the intracellular and extracellular S100A8 feedback loop.

关键词： colorectal cancer epithelial-mesenchymal transition metastasis prognosis transforming growth factor-β upstream transcription factor 2 S100 calcium-binding protein A8

662 A/G gene variation in human tumor necrosis factor receptor superfamily,member 9(TNFRSF9)

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Frontiers of Medicine 2008年第3期2卷 283-285页

作者： Yanchun QU Ze YANG liang sun Linong JI Tianjin Institute of Urology The Second Hospital of Tianjin Medical UniversityTianjin 300211China Beijing Institute of Geriatrics Beijing HospitalMinistry of HealthBeijing 100730China Endocrinology Department The People’s HospitalBeijing UniversityBeijing 100044China

The aim of this paper is to report a new coding variance of the TNFRSF9 gene,a candidate for auto-immune diseases.We found the variation in two families with type 2 diabetes mellitus by D-HPLC mutation screening method and confirmed our results by direct sequencing and PCR-RFLP.Although without changing the amino acid coding,the variance may have an effect on codon usage and play a role in disease development,such as type 2 diabetes mellitus.However,we cannot define the role of this variance because the frequency of the minor allele is low in the Chinese population and no homozygote of the variance was found.More research in multiple populations will be necessary to define the role of this variance.

关键词： diabetes mellitus single nucleotide polymorph-ism TNFRSF9 gene antigens,CD137 immune regulation

植被根系对土体水力学特性影响的现状与定量分析

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西北大学学报（自然科学版） 2024年第1期54卷 53-62页

作者：杨几肖涛孙靓史亚瑞李萍西北大学地质学系/大陆动力学国家重点实验室陕西西安710069

在全球气候变暖和“双碳”战略的背景下,植被护坡成为一种潜在的碳负排放边坡加固和侵蚀控制手段。植被根系的发育可以改变土体结构和水力学特性,进而影响边坡的稳定性。虽然一些试验研究已经探讨了特定条件下植被对土体水力学特性的影... 详细信息

在全球气候变暖和“双碳”战略的背景下,植被护坡成为一种潜在的碳负排放边坡加固和侵蚀控制手段。植被根系的发育可以改变土体结构和水力学特性,进而影响边坡的稳定性。虽然一些试验研究已经探讨了特定条件下植被对土体水力学特性的影响,但是对于植被根系改变土体水力学特性的一般规律尚不清楚。该文从植被蒸腾作用、根系物理作用以及根系生物化学作用3个方面入手,收集并梳理了近年来国内外相关研究,分析并总结了植被根系改变土体水力学特性的作用机理,且对已有试验数据进行了统计分析。指出植被根系对土体水力学特性的改变取决于植被蒸腾、根系物理作用和根系生物化学作用三者的相对贡献,同时受根系类型、土体类型及生长阶段等因素的影响。因此,植被根系对土体水力学特性的影响十分复杂,更全面广泛的研究对于揭示植被护坡机理是亟需的。最后,探讨了植被根系影响土体水力学特性的研究空白和未来趋势。

关键词：植被根系 SWRC 渗透系数土体吸力蒸腾作用

Identification and characterization of genes that control fat deposition in chickens

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Journal of Animal Science and Biotechnology 2014年第1期5卷 22-37页

作者： Hirwa Claire D'Andre Wallace Paul Xu Shen Xinzheng Jia Rong Zhang liang sun Xiquan Zhang Rwanda Agriculture Board Research Department Department ofAnimal Genetics Breeding and Reproduction College of Animal ScienceSouth China Agricultural University Council for Scientific and Industrial Research (CSIR) AnimalResearch Institute

Background： Fat deposits in chickens contribute significantly to meat quality attributes such as juiciness, flavor, taste and other organoleptic properties. The quantity of fat deposited increases faster and earlier in the fast- growing chickens than in slow-growing chickens. In this study, Affymetrix Genechip~ Chicken Genome Arrays 32773 transcripts were used to compare gene expression profiles in liver and hypothalamus tissues of fast-growing and slow-growing chicken at 8 wk of age. Real-time RT-PCR was used to validate the differential expression of genes selected from the microarray analysis. The mRNA expression of the genes was further examined in fat tissues. The association of single nucleotide polymorphisms of four lipid-related genes with fat traits was examined in a F2 resource population. Results： Four hundred genes in the liver tissues and 220 genes hypothalamus tissues, respectively, were identified to be differentially expressed in fast-growing chickens and slow-growing chickens. Expression levels of genes for lipid metabolism （SULTIB1, ACSBG2, PNPLA3, LPL, AOAH） carbohydrate metabolism （MGAT4B, XYLB, GBE1, PGM1, HKDCl）cholesttrol biosynthesis （FDPS, LSS, HMGCR, NSDHL, DHCR24, IDI1, MEI） HSD17B7 and other reaction or pro- cesses （CYPIA4, CYP1A1, AKR1BI, CYP4V2, DDO） were higher in the fast-growing White Recessive Rock chickens than in the slow-growing Xinghua chickens. On the other hand, expression levels of genes associated with multicellular organism development, immune response, DNA integration, melanin biosynthetic process, muscle organ develop- ment and oxidation-reduction （FRZB, DMD, FUT8, CYP2C45, DHRSX, and CYP2C18） and with glycol-metabolism （GCNT2, ELOVL d, and FASN）, were higher in the XH chickens than in the fast-growing chickens, fiT-PCR validated high expression levels of nine out of 12 genes in fat tissues. The G1257069A and T1247123C of the ACSBG2 gene were significantly associated with abdominal fat weight. The G4928024A of the FASN gene were significantly associ- ated with fat band

关键词： Chicken Fat deposition Genes