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肠道菌群体外酵解不同种类单糖研究

陕西科技大学学报 2025年第1期43卷 35-45页

作者：郝俊宇孙玉姣高润凝姚佳轩陕西科技大学食品科学与工程学院陕西西安710021 陕西农产品加工技术研究院陕西西安710021

碳水化合物的结构特征影响着其被微生物的利用效果,为了探究其结构对肠道菌群的影响,本文从单糖组成角度入手,研究了以葡萄糖、甘露糖、阿拉伯糖、半乳糖、岩藻糖、木糖、鼠李糖、葡萄糖醛酸和半乳糖醛酸这九种单糖作为碳源,在进行体外... 详细信息

碳水化合物的结构特征影响着其被微生物的利用效果,为了探究其结构对肠道菌群的影响,本文从单糖组成角度入手,研究了以葡萄糖、甘露糖、阿拉伯糖、半乳糖、岩藻糖、木糖、鼠李糖、葡萄糖醛酸和半乳糖醛酸这九种单糖作为碳源,在进行体外培养的过程中,肠道菌群及其代谢产物发生的变化.主要检测了OD_(600)、糖消耗量、短链脂肪酸和乳酸含量等指标.经过筛选后,对七种中性单糖混合发酵的培养基进行了单糖组成分析,明确了七种中性单糖在酵解过程中的被利用顺序.以16S rRNA高通量测序分析了肠道菌群群落多样性和丰度变化,发现不同单糖在被乳酸杆菌等有益菌利用的过程中存在竞争关系,甘露糖和半乳糖有利于肠道中的乳酸杆菌属等有益菌的生长繁殖,研究结果将为多糖与肠道菌群的构效关系研究提供了理论依据.

关键词：单糖组成体外酵解短链脂肪酸肠道菌群多样性分析

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联合FOD-sCARS的土壤有机质高光谱机器学习估测模型

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光谱学与光谱分析 2025年第1期45卷 204-212页

作者：吴梦红窦森林楠姜然哲陈思李佳璇付佳伟梅显军吉林农业大学资源与环境学院吉林长春130118 吉林建筑大学测绘与勘查工程学院吉林长春130118 吉林大学生物与农业工程学院吉林长春130115

土壤有机质(SOM)含量是表征土壤质量的关键指标,在全球碳循环系统中发挥重大作用。快速准确的SOM估算和空间制图对土壤碳库估算、作物生长监测和耕地规划管理具有重要意义。利用传统方法监测区域性SOM含量耗时费力,基于高光谱遥感影像建... 详细信息

土壤有机质(SOM)含量是表征土壤质量的关键指标,在全球碳循环系统中发挥重大作用。快速准确的SOM估算和空间制图对土壤碳库估算、作物生长监测和耕地规划管理具有重要意义。利用传统方法监测区域性SOM含量耗时费力,基于高光谱遥感影像建立SOM估测模型是现在较为合理有效的方法。为探索解决目前高光谱遥感影像建立SOM含量估测模型存在光谱数据冗余、光谱数据特征提取精度低、小样本模型泛化能力不强的问题,选择位于青海省湟中县的研究区,共采集67个土壤样本。获取资源1号02D(ZY1-02D)高光谱遥感影像并进行预处理得到样点像元光谱数据,采用分数阶微分变换(FOD)方法挖掘与SOM含量具有响应关系的敏感波段,以0.2为一个步长,利用相关性阈值法对比分析不同阶次微分处理数据挖掘能力;运用稳定性竞争性自适应重加权采样算法(sCARS)去除高光谱冗余数据获取建模特征波段,选择随机森林(RF)、极端梯度提升树、极限学习机和岭回归机器学习作为建模算法,以全波段和特征波段光谱数据分别作为模型输入变量构建SOM估测模型进行高光谱反演研究工作;最后根据最优特征变量和建模算法,基于ZY1-02D遥感影像进行了SOM空间分布制图。结果表明:采用FOD变换相比整数阶可以大大提高波段与SOM含量间的相关性,挖掘出更多细微的与SOM含量产生响应关系的光谱波段,其中0.8阶微分变换效果最优,较原始波段相比相关系数最大值提高了0.546;相较于全波段光谱数据,采用sCARS特征提取方法获取特征波段构建模型的估测精度得到较大提升,说明sCARS可以有效提升建模数据的质量,提升模型预测精度。建模算法中RF表现最优,R_(p)^(2)(模型决定系数)达到0.766,RPD达到1.86,较全波段建模结果R_(p)^(2)提升约7.58%;基于FOD-sCARS和RF实现了区域SOM含量估测制图。研究进一步验证利用星载高光谱遥感影像是实现区域SOM估测制图的可靠途径,研究结果可为估测区域SOM含量提供新思路,为利用星载高光谱遥感影像绘制SOM含量空间分布图提供了数据支持。

关键词：高光谱遥感影像分数阶微分变换稳定性竞争性自适应重加权采样算法土壤有机质随机森林

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新冠疫情背景下苏宁易购的利润表研究

江苏商论 2025年第1期 11-14,52页

作者：隋佳轩杨西平西藏民族大学陕西咸阳712082

随着资本市场的不断发展和各种财务指标分析的完善,中国的财务分析方法日趋成熟,尤其是利润表方面的分析,与其有关的研究成果逐渐趋向于完善。由于苏宁易购在电商行业占据了极其重要的地位,所以利润表分析能够更清晰地披露苏宁易购在发... 详细信息

随着资本市场的不断发展和各种财务指标分析的完善,中国的财务分析方法日趋成熟,尤其是利润表方面的分析,与其有关的研究成果逐渐趋向于完善。由于苏宁易购在电商行业占据了极其重要的地位,所以利润表分析能够更清晰地披露苏宁易购在发展战略中所出现的问题。因此,利润表分析尤其重要,所以文本将从利润表的角度对苏宁易购进行分析。

关键词：利润表苏宁易购财务分析

Forecast of cosmological constraints with superluminous supernovae from the Chinese Space Station Telescope

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Science China(Physics,Mechanics & Astronomy) 2024年第10期67卷 128-138页

作者： xuan-Dong jia jian-Ping Hu Fa-Yin Wang Zi-Gao Dai School of Astronomy and Space Science Nanjing UniversityNanjing 210093China Key Laboratory of Modern Astronomy and Astrophysics(Nanjing University) Ministry of EducationNanjing 210093China Department of Astronomy University of Science and Technology of ChinaHefei 230026China

Superluminous supernovae(SLSNe)are a class of intense celestial events that can be standardized for measuring cosmological parameters,bridging the gap between type Ia supernovae and the cosmic microwave *** this work,we discuss the cosmological applications of SLSNe from the Chinese Space Station Telescope(CSST).Our estimation suggests that SLSNe rate is biased tracing the cosmic star formation rate,exhibiting a factor of(1+z)^(1.2).We futher predict that CSST is poised to observe~360 SLSNe in the 10 square degrees ultra-deep field survey within a span of 2.5 years.A stringent constraint on cosmological parameters can be derived from their peak-color *** is anticipated to uncover a substantial number of SLSNe,contributing to a deeper understanding of their central engines and shedding light on the nature of dark energy at high redshifts.

关键词： supernovae cosmology cosmological constant

Numerical evaluation of segmental tunnel lining with voids in outside backfill

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Underground Space 2022年第5期7卷 786-797页

作者： jia-xuan Zhang Ning Zhang Annan Zhou Shui-Long Shen Department of Civil Engineering School of Naval ArchitectureOceanand Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China MOE Key Laboratory of Intelligent Manufacturing Technology Department of Civil and Environmental EngineeringCollege of EngineeringShantou UniversityShantouGuangdong 515063China Discipline of Civil and Infrastructure School of EngineeringRoyal Melbourne Institute of Technology(RMIT)Victoria 3001Australia

This paper presents a numerical investigation of the mechanical behaviour of segmental linings owing to the existence of voids in the composite *** composite lining was formed by mining outside and shield tunnelling inside with backfill in *** element method was conducted to analyse the axial forces and bending moment for voids of different diameters at different *** results show that the axial forces in the transverse section increase near the crown and then invert and decrease on the left and right sides with an increase in the void centre angle(β)measured from the vertical *** increase in void diameter(d<300 mm)induces an increase in the axial force on the left and right sides when β=45°and 90°,while it decreases near the crown and *** occurrence of voids leads to an increase in the bending moment in the entire segment section with an angle β.

关键词： Jointly constructed tunnel Composite lining Voids Axial force Bending moment

Association between KITLG Gene Polymorphisms and Testicular Germ Cell Tumors:A Systematic Review and Meta-analysis

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Current Medical Science 2019年第5期39卷 702-706页

作者： jia-xuan QIN Zong-long CAI Yu-feng YANG Jin-chun XING xuan ZHUANG Department of Urology Surgery Center of Diagnosis and Treatment of Urinary System Diseasesthe Key Laboratory of Urinary Tract Tumors and Calculi of Xiamen Citythe First Affiliated Hospital of Xiamen UniversityXiamen 361003China The First Clinical Medical School of Fujian Medical University Xiamen 361003China

It has been reported that c-KIT ligand(KITLG)gene polymorphisms may be associated with testicular germ cell tumors(TGCT).Owing to mixed and inconclusive results,we con ducted a systematic review and meta-analysis to summarize and clarify this association.A systematic search of studies on the association between KITLG gene polymorphisms and TGCT susceptibility was conducted in *** ratios and 95%confidence intervals were used to pool the effect *** articles were included in our systematic review and *** with adenine(A),KITLG rs995030 guanine(G)might be associated with increased risk of *** are insufficient data to fully confirm the association between KITLG rs4474514 and TGCT ***-designed studies with larger sample size and more subgroups are required to validate the risk identified in the current meta-analysis.

关键词： c-KIT ligand single nucleotide polymorphisms testicular germ cell tumors metaanalysis

Comparison of Clinic and Ambulatory Blood Pressure in Response to Antihypertensive Drugs in Chinese Patients

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Biomedical and Environmental Sciences 2007年第4期20卷 279-283页

作者： XIAO-RU CHENG YANG WANG BO HU xuan jia WEI LI National Center for Cardiovascular Diseases Cardiovascular Institute ＆ Fuwai Hospital Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100037 China

To compare the difference between 24-h ambulatory blood pressure （ABP） and trough clinic blood pressure （CBP） after 8 weeks of therapy. Methods The study used meta-regression analysis to summarize three randomized, double-blind, active controlled trials in order to compare the difference between the magnitude of the reduction in 24-h average ABP and CBP Patients. Chinese patients with seated diastolic blood pressure （SDBP） 95-115 mmHg and ambulatory diastolic blood pressure （ADBP）≥85 mmHg. Results The average age of 126 patients was 47.7 ＋ 8.3 years, ranging from 25 to 67 （95 males and 31 females）. All regimens reduced 24-h ABP and CBP after 8 weeks of treatment. In the 126 patients the baseline 24-h SBP and DBP values （142.7/94.4 mmHg） were markedly lower than those for clinic values （152.6/102.6 mmHg; P〈0.0001）. Similarly, the 24-h SBP and DBP values （132.7/87.7 mmHg） in week 8 were markedly lower than the clinic values （138.9/92.7 mmHg; P〈0.0001）. The differences between the treatment-induced reductions in 24-h ABP and CBP were statistically significant （the difference was 3.7/3.3 mmHg for SBP/DBP, P=***69/P〈O.O001）. Conclusion All regimens significantly reduced seated CBP and ABP. The effect of antihypertensive treatment was greater on CBP than that on ABP, suggesting that assessment on effectiveness of an antihypertensive treatment using CBP readings only has to be carefully interpreted, and a more systematic application of ABP monitoring should be adopted.

关键词： Ambulatory blood pressure Antihypertensive treatment Clinic blood pressure Essential Hypertension

Conditional survival probability of distant-metastatic hepatocellular carcinoma: A population-based study

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World Journal of Gastrointestinal Oncology 2023年第11期15卷 1874-1890页

作者： Yong-Ping Yang Cheng-Jun Guo Zhao-xuan Gu Jun-Jie Hua jia-xuan Zhang jian Shi Department of General Surgery The Second Hospital of Jilin UniversityChangchun 130041Jilin ProvinceChina

BACKGROUND The prognosis of many patients with distant metastatic hepatocellular carcinoma(HCC)improved after they survived for several *** with tradi-tional survival analysis,conditional survival(CS)which takes into account changes in survival risk could be used to describe dynamic survival *** To evaluate CS of distant metastatic HCC *** Patients diagnosed with distant metastatic HCC between 2010 and 2015 were extracted from the Surveillance,Epidemiology and End Results *** and multivariate Cox regression analysis were used to identify factors for overall survival(OS),while competing risk model was used to identify risk factors for cancer-specific survival(CSS).Six-month CS was used to calculate the probability of survival for an additional 6 mo at a specific time after initial diagnosis,and standardized difference(d)was used to evaluate the survival differences between *** were constructed to predict ***α-fetoprotein expression,higher T stage(T3 and T4),N1 stage,non-primary site surgery,non-chemotherapy,non-radiotherapy,and lung metastasis were independent risk factors for actual OS and CSS through univariate and multivariate *** survival rates decreased over time,while CS rates gradually *** for the 6-month CS,the survival difference caused by chemotherapy and radiotherapy gradually disappeared over time,and the survival difference caused by lung metastasis ***,the influence of age and gender on survival gradually *** were fitted for patients who have lived for 2,4 and 6 mo to predict 6-month conditional OS and CSS,*** area under the curve(AUC)of nomograms for conditional OS decreased as time passed,and the AUC for conditional CSS gradually *** CS for distant metastatic HCC patients substantially increased over *** dynamic risk factors,nomograms constructed at a specific time could predict more accur

关键词： Conditional survival Hepatocellular carcinoma Distant metastasis Prognosis Nomogram

Total Synthesis of (±)-Celaphanol A

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Chinese Chemical Letters 2002年第9期13卷 830-831页

作者： Ping Yan BIE Cheng Lu ZHANG xuan jia PENG Xin Fu PAN Department of Chemistry National Laboratory of Applied Organic ChemistryLanzhou UniversityLanzhou 730000

The first total synthesis of (?-Celaphanol A was accomplished starting from cyclocitral and 3,4-dimethoxy benzyl chloride via a six-step process, in which the intramolecular cyclization of ketone 4 with BF3稥t2O affor... 详细信息

关键词： (±)-celaphanol A Diterpene Total synthesis