submitted time 2024-04-03 Cooperative journals: 《农业图书情报学报》
Abstract： [Purpose/Significance] The introduction of national poverty alleviation policies and rural revitalization strategies has thrust the issue of education for left-behind children into the spotlight of scholarly attention. Education, far beyond serving as a mere instrument for personal growth and human capital accumulation for left-behind children, emerges as a pivotal measure in consolidating rural poverty alleviation endeavors and breaking the transmission of intergenerational poverty in China. It stands as a vital force propelling the future of rural revitalization. Yet, the existing literature on the education of left-behind children remains sporadic and dispersed. A more profound organizational effort, integrating, synthesizing, and evaluating this scattered literature, is imperative to establish a foundational framework for future research, fostering more cohesive and focused research endeavors. Presently, literature review studies primarily fall into three categories: qualitative review methods, meta-analysis, and bibliometric analysis methods employing tools like Citespace. This study sets out to achieve a systematic and comprehensive understanding of education-related issues for rural left-behind children through text mining methods grounded in topic models. [Method/Process] The advent of artificial intelligence and machine learning technologies has empowered the processing and analysis of vast amounts of textual data. Previous research, employing latent dirichlet allocation (LDA) topic models, successfully mined texts related to teacher team construction reform policies, internationalization in higher education literature, news reports, and online comments. In this study, a corpus was meticulously constructed using abstract texts extracted from 2037 journal articles published between 2002 and 2023. The structural topic model (STM) was chosen for topic modeling, overcoming the limitations associated with LDA, with a specific emphasis on exploring the diversity and dynamism of topics within the existing literature. [Results/Conclusions] The culmination of this research effort identified eight distinct research themes: psychological well-being, factors leading to left-behind children, macro-level coping strategies, types of guardianship, review studies, family education, media literacy, and micro-level coping strategies. By synergizing document metadata information, the study systematically unraveled the evolving trends of these topics over time, providing crucial insights into potential shifts in the focus of left-behind children's education research. It is essential to note that this study, while collecting abstracts instead of full texts, may not capture the entirety of information contained in complete research articles. Future research endeavors should explore left-behind children's education more comprehensively, leveraging full-text mining techniques for a more nuanced understanding of this critical subject.
Subjects: Management Science >> Enterprise Management submitted time 2024-01-13
Abstract： Abstract: The online marketing model can expand the business development boundary of Baijiu sales companies through marketing effect, marketing positioning and marketing innovation. However, in the online marketing model of Baijiu sales companies, there are still problems such as the shackles of traditional consumption concepts, imperfect laws and regulations, and lack of online marketing talents. Based on this, this paper proposes to optimize the convenience of online payment, consolidate the talent base of online marketing, and update the consumption concept, so as to help Baijiu sales companies develop high-quality online marketing models.
Key words: Liquor company; Online marketing; Marketing risks; Response strategies
Subjects: Physics >> General Physics: Statistical and Quantum Mechanics, Quantum Information, etc. submitted time 2023-04-24
Abstract： Thermodynamics coupling kinetics includes three levels, namely thermodynamic stability, thermo-kinetic correlation and generalized stability. Taking nanostructured (NC) materials as examples, material design is reinterpreted and discussed from the above three levels, including thermal stability related to strength, thermo-kinetic correlation related to plasticity, and generalized stability design aiming for high strength and high plasticity
Subjects: Medicine, Pharmacy >> Clinical Medicine submitted time 2023-03-31 Cooperative journals: 《中国全科医学》
Abstract： Background How to implement effective and reasonable support and comprehensive services for patients with advanced cancer during chemotherapy is an issue worthy of attention in community health services at present.. According to the latest data，the mortality rate of malignant tumors among residents in Shanghai has become the second place after cardiovascular and cerebrovascular diseases. The current attention to patients with advanced cancer during chemotherapy is also gradually increasing. Therefore，this study tries to understand the demand for primary care among such patients and the influencing factors. Objective To investigate the demand and influencing factors for community health services during chemotherapy of partial patients with advanced cancer in Shanghai，and to explore how to develop community interventions and services to address the demand of such patients. Methods Patients with advanced cancer during chemotherapy who regularly visited or hospitalized at Shanghai Ninth People's Hospital，Wusong Hospital and Shanghai Baoshan Hospital of Integrated Traditional Chinese and Western Medicine from December 2021 to March 2022 were selected as the study subjects. Based on previous relevant questionnaires，government specifications and interview results，the final version of the demand for community health services of partial patients with advanced cancer during chemotherapy in Shanghai was formed，with a total of 3 demand dimensions （psychological，medical care，social support）and 38 demand items. The contents include patients' general information（demographic and sociological information：gender，age，religious beliefs，education level，marital status，source of medical expenses， disposable monthly household income，whether to participate in a patient group；tumor diagnosis：type and time of diagnosis，pain score，combining with other diseases），6 items of psychological and psychological demand，24 items of medical care demand，and 8 items of social support demand. A 3-point scale was adopted：1 was unnecessary，2 was necessary，and 3 was very necessary. The higher the score，the higher the degree of patients' demand，which was ranked according to the average score of each demand item. Univariate and multivariate Logistic regression analyses were used to explore the influencing factors of the demand for community health services of patients with advanced cancer during chemotherapy. Results The average scores of each demand dimension were ranked in order of psychological demand（2.31 points），medical care demand（2.27 points）and social support demand（2.18 points）. The top five average scores of all demand items were“preparation of biochemical tests such as routine blood，liver and kidney functions before chemotherapy”（2.48 points），“education on chemotherapy knowledge”（2.48 points），“care of PICC catheterization during chemotherapy”（2.45 points），“management of myelosuppression after chemotherapy”（2.43 points）" and“providing of updated information on treatment，examination and rehabilitation”（2.42 points），mainly focus on the medical care demand dimension. Multivariate Logistic regression analysis showed that education level and disposable monthly household income were influencing factors of psychological demand of patients with advanced cancer during chemotherapy（ P<0.05）；age and medical expenses were influencing factors of medical care of patients with advanced cancer during chemotherapy（ P<0.05）；age and whether to join a patient group were influencing factors of social support of patients with advanced cancer during chemotherapy（ P<0.05）. Conclusion Patients with advanced cancer during chemotherapy have specific demand for community health services，with different levels of demand in psychological，medical care and social support dimensions，which are influenced by various factors such as age，education level，and household income. This study provides references for community health service centers to carry out relevant medical services. In the future，new service items
with high level of demand can be piloted，community interventions such as psychological and medical care for patients with advanced cancer during chemotherapy，and their quality of survival should be followed up.
Subjects: Biology >> Botany >> Applied botany submitted time 2021-12-19 Cooperative journals: 《广西植物》
Abstract： Herba Xanthii is a traditional folk medicinal plant.The 50% ethanol eluting faction of Xanthium mongolicum in Jiangxi had significant activity to inhibit necroptosis. In order to investigate the chemical constituents, the active fractions of X. sibiricum were isolated and purified by various chromatographic methods such as repeated silica gel column chromatography, Sephadex LH-20 column chromatography, preparative high performance liquid chromatography and recrystallization to yield 14 compounds. Their structures were established on the basis of NMR, MS spectraoscopic analyses and comparison with lirerature date. Fourteen compounds were isolated from the active part and identified as hydroxydihydrobovolide(1), raspberry ketone(2), salicyl alcohol(3), 4-hydroxyl-acetophenone(4), 4-hydroxybenzaldehyde(5), ethyl caffeate(6), ferulaldehyde(7), isoscopletin(8), 3,3'-bis(3,4-dihydro-4-hydroxy-6 -methoxy-2H-1-benzopyran)(9)，axillarin (10)，quercetin (11)，(+) pinoresinol(12)， β-sitosterol(13) and palmatic acid(14). Compounds 1, 2, 3, 4, 7, 8, 9, 10 were isolated from Xanthium mongolicum for the first time．
Subjects: Astronomy >> Astrophysical processes submitted time 2021-09-29 Cooperative journals: 《天文研究与技术》
Abstract：射电天文接收机中频系统是接收机的重要组成部分，接收机的L、S、C、K波段的左圆极化和右圆极化信号在高频仓通过下变频成为中频信号。中频信号通过同轴电缆传送到观测室。观测室距离射电望远镜高频仓较远，因此线损较大，且不同频率的信号损耗不同，频率越高损耗越大，导致中频信号功率较小且增益平坦度随频率增加而降低。设计了四通道均衡放大模块，提高中频信号增益并补偿增益平坦度。该模块的均衡器采用了集总元件和微带线相结合的方式，具有结构紧凑、易于集成、成本低的优点。测试结果表明，在6倍频带宽内，均衡量≥8dB，均衡后功率平坦度≤3.5dBm，回波损耗≤-15dB，满足了射电天文中频检测系统的要求。
Subjects: Biology >> Botany >> Applied botany submitted time 2020-10-20 Cooperative journals: 《广西植物》
Abstract：毛梗豨莶草(Siegesbeckia glabresce)的乙酸乙酯萃取部位具有显著的抑制细胞坏死性凋亡(necroptosis)的活性。为明确毛梗豨莶草的活性成分，对毛梗豨莶草乙酸乙酯萃取部位进行了化学成分分离。采用正相硅胶柱色谱谱( 二氯甲烷∶甲醇20∶1～0∶1)、反相ODS柱色谱(30%～100% 甲醇)，Sephadex LH-20柱色谱、重结晶等方法进行分离和纯化，根据理化性质和波谱数据进行结构鉴定。从毛梗豨莶乙酸乙酯部位分离并鉴定了9个化合物，分别为3,7-二甲氧基槲皮素（1），芹菜素（2），奥卡宁（3），okanin-4'-O-β-D-6''-trans-p-coumaroylglucoside（4），1H-Indole-3-carbaldehyde（5），对羟基苯甲醛（6），3,5-二甲氧基-4-羟基苯甲醛（7），3,4-divanillyltetrahydrofuran（8），buddlenol D（9）。除化合物1和6外，其余7个化合物均为首次从豨莶属植物中分离得到。
Subjects: Biology >> Botany >> Applied botany submitted time 2020-08-02 Cooperative journals: 《广西植物》
Abstract：为了阐明不同生态环境条件下沙生植物沙鞭的结实规律，该文对沙鞭137 个种群结实情况进行了实地观察，发现沙鞭种子的结实情况可被划分为无种子、种子饱满和种子不饱满3 种类型；在此基础上，该文采用聚类分析、Kruskal-Wallis 检验和典范对应分析（CCA）等方法探究沙鞭种群结实情况与22 个地理气候因子的相关性。结果表明：沙鞭137 个种群按照地理气候因子不同聚为3个组；Kruskal-Wallis 检验显示沙鞭3 个组间种子结实情况差异不显著（P = 0.269），即沙鞭种群间种子结实与其所处的地理气候因子无直接相关性；同时，典范对应分析（CCA）表明沙鞭种群间种子结实情况差异也不显著（P > 0.05），但地理气候因子与种子饱满度以及无种子特征具有显著相关性，其中海拔和降雨因子（bio12-bio19）与种子饱满度呈正相关，经纬度和温度因子（bio4，bio7）与种子饱满度呈负相关，而无种子特征仅与最湿季平均温度（bio8）呈正相关。地理气候因子对沙鞭天然种群有性繁殖（有种子）重要性高于无性繁殖（无种子），表明制约沙生植物沙鞭有性繁殖的环境因子复杂，其无性繁殖可能是种群数量稳定的适应性表现。
Subjects: Biology >> Zoology submitted time 2018-12-24 Cooperative journals: 《动物营养学报》
Abstract：本试验旨在研究发酵豆粕替代鱼粉对黄姑鱼幼鱼生长性能、血清生化指标和肝脏中胰岛素样生长因子-Ⅰ（IGF-Ⅰ）基因相对表达量的影响，以确定黄姑鱼幼鱼饲料中发酵豆粕替代鱼粉的适宜比例。试验首先以秘鲁鱼粉、豆粕、小麦蛋白粉为主要蛋白质源，鱼油、大豆油和大豆卵磷脂为主要脂肪源，配制含45%鱼粉的基础饲料，然后以发酵豆粕替代基础饲料中0（FSM0组，作为对照组）、10%（FSM10组）、20%（FSM20组）、30%（FSM30组）、40%（FSM40组）和50%（FSM50组）的鱼粉，并在除对照组外的各组饲料中添加适量赖氨酸和蛋氨酸，以保持各组赖氨酸和蛋氨酸含量的一致，配制6种等氮（蛋白质水平为50%）等脂（脂肪水平为12%）的试验饲料。选取初始体重为(31.24±0.02) g的黄姑鱼幼鱼360尾，随机分为6组，每组3个重复，每个重复20尾，养殖试验持续8周。结果表明：FSM10、FSM20和FSM30组黄姑鱼幼鱼的增重率、特定生长率和饲料系数与对照组相比没有显著性差异（P>0.05），而FSM40和FSM50组黄姑鱼幼鱼的增重率和特定生长率显著低于对照组（P0.05）。发酵豆粕替代不同比例鱼粉对黄姑鱼幼鱼的肝体比、脏体比和肥满度没有产生显著性影响（P>0.05）。FSM40和FSM50组黄姑鱼幼鱼血清中谷草转氨酶（AST）活性显著高于其他组（P<0.05），且FSM50组黄姑鱼幼鱼血清中的谷丙转氨酶（ALT）活性显著高于对照组和FSM10组（P<0.05）。FSM50组黄姑鱼幼鱼肝脏中IGF-Ⅰ基因相对表达量显著低于对照组（P<0.05）。综合各指标，本试验条件下，发酵豆粕替代饲料中20%~30%的鱼粉较为适宜，过高的替代比例会降低黄姑鱼幼鱼的生长性能和饲料利用率。
Subjects: Computer Science >> Integration Theory of Computer Science submitted time 2018-08-13 Cooperative journals: 《计算机应用研究》
Abstract： Fault diagnosis is very important in ensuring system stability. Most of traditional fault diagnosis research ignored characteristics of local structure. For that problem under PMC model, the definition of node diagnosis was introduced. And through the study by nodes diagnosis, obtained the sufficient condition of the node diagnosiability and got a new t-diagnosis algorithm called STFDA. Finally, an analysis from the angle of node diagnosis of n-dimensional hypercube network and n-dimensional star network was performed in order to test the validity of the sufficient conditions. Algorithm performed a fault diagnosis to the two kinds of network at last. Indeed, the implementation of the sufficient condition and algorithm got the help of a new structure called ST. And algorithm’s time complexity was proved to be O(N δ) , with δ equal to the maximum degree of node in network, which was significantly reduced compared with others algorithm.
Subjects: Medicine, Pharmacy >> Preclinical Medicine submitted time 2018-01-25 Cooperative journals: 《南方医科大学学报》
Abstract： Objective To evaluate the prognostic value of preoperative serum carcinoembryonic antigen (CEA) level in patients with stage I-III colorectal cancer. Methods The clinicopathological data and prognosis were retrospectively analyzed for 393 patients with colorectal cancer treated in our hospital from January, 2003 to December, 2013. Of these patients, 136 had elevated serum CEA level (≥5 ng/mL) and 257 did not show serum CEA elevation (<5 ng/mL). Results The two groups of patients showed significant differences in the tumor size, degree of tumor differentiation and lymph node metastasis (P<0.05). Cox proportional hazards model suggested that an elevated preoperative CEA level was a risk factor for survival and tumor recurrence, and increased the risks of death and tumor recurrence by 1.59 and 1.89 folds, respectively. Compared with the patients without CEA elevation, those with elevated CEA level had a significantly higher mortality rate (28.7% vs 19.8%, P< 0.05) and tumor recurrence rate (32.4% vs 19.1% , P<0.05) with a significantly lower cumulative total survival rate and cumulativedisease-freesurvivalrate(P<0.05);thesameresultswerealsofoundinstage-Ⅲpatients(P<0.05).ConclusionsNew survival and recurrence data can be generated by incorporating serum CEA level in TNM staging system for more accurate prognosticassessmentofthepatients.
Subjects: Library Science，Information Science >> Information Science submitted time 2017-10-11 Cooperative journals: 《数据分析与知识发现》
Abstract： [Objective] This study aims to effectively storage, manage and reuse scientific data with the help of a specialized data repository management system, the TeamDR, for the research teams. [Context] TeamDR is a Web tool helping scientific research team members organize, storage, manage and share data. It was developed by Java and offered cloud-based and standalone services. [Methods] We first designed a dynamic metadata template to organize and manage scientific research data. MongoDB was then adopted to improve data storage capacity and query performance. [Results] TeamDR stores and manages the scientific research data effectively with the support of, dynamic metadata template, categorized sharing control, and full-text search of metadata. Users’ feedbacks show that TeamDR meets the demands of scientific data storage and management. [Conclusions] TeamDR effectively addresses the issues of scientific data storage and management, data sharing and collaboration, data discovery and linking. However, this system’s usability, completeness and extensibility could be further improved.
Subjects: Biology >> Zoology submitted time 2017-10-10 Cooperative journals: 《动物营养学报》
Abstract：试验旨在研究肝脏香、奶香、甜味剂和大肠香等4种饲料调味剂对育成期雄性蓝狐采食量、营养物质消化率、氮代谢和生长性能的影响。试验采用单因子试验设计，选取体况健康的育成期雄性蓝狐50只，随机分成5组，每组10个重复，各组动物个体间体重差异不显著。对照组（Ⅰ组）饲喂基础饲粮，试验组（Ⅱ、Ⅲ、Ⅳ、Ⅴ组）分别饲喂在基础饲粮中添加肝脏香、奶香、甜味剂和大肠香的饲料调味剂的试验饲粮，添加量分别为500、500、120、500 mg/kg。试验结果表明：1）与Ⅰ组相比，Ⅱ和Ⅳ组极显著的提高了干物质采食量（P0.05）；Ⅲ、Ⅳ、Ⅴ组蛋白质消化率极显著提高（P0.05）；Ⅳ组粪氮显著降低(P0.05）；平均日增重各组之间差异不显著(P>0.05)，但以Ⅰ组最低，Ⅱ、Ⅲ、Ⅳ、Ⅴ组分别高于Ⅰ组7.99%、3.27%、6.19%、7.37%；料重比从低到高顺序分别为Ⅳ、Ⅲ、Ⅱ、Ⅴ、Ⅰ组，但各组之间差异不显著(P>0.05)。在本试验条件下，饲粮中添加肝脏香、奶香、甜味剂均提高了蓝狐的干物质采食量和营养物质消化率，提高了饲料的利用率，其中甜味剂效果最好。
Subjects: Materials Science >> Materials Science (General) submitted time 2016-11-15 Cooperative journals: 《金属学报》
Abstract：基于经典相变理论，分析相变中关键热力学/动力学参量，提出相变热力学/动力学相关性概念；结合低合金钢TMCP涉及相变的实验研究，总结热力学驱动力、动力学能垒与相变条件间关联；进而探讨相变中热力学/动力学相关性；最后对热力学/动力学相关性的潜在应用进行了展望。
Subjects: Materials Science >> Materials Science (General) submitted time 2016-11-14 Cooperative journals: 《中国腐蚀与防护学报》
Abstract：采用动电位极化曲线分析了X100和X80管线钢在0.5 mol/L NaHCO3溶液中的极化行为，通过电流密度-时间曲线以及Mott-Schottky曲线考察了两种钝化膜的生长机制和钝化膜的半导体性质，借助电容测量和点缺陷模型(PDM)计算了两种钝化膜内的缺陷密度和缺陷扩散系数。结果表明：两种管线钢在该介质中都存在一个很宽的钝化区间，表面钝化膜的生长均受电迁移和溶解—沉积混合机制控制，钝化膜均为n型半导体。但与X80管线钢相比，X100钢具有更低的自腐蚀电流密度和维钝电流密度，更高的击穿电位。X100管线钢表面钝化膜也更为致密、均匀、稳定，钝化膜的施主密度更低，缺陷扩散系数约是X80管线钢的1/3。因此，X100比X80管线钢表现出更好的抗均匀腐蚀性能和抗点蚀性能。
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