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21.
李勇军  江莹 《运筹与管理》2021,30(11):60-64
小学教育是教育阶段的基础,也是我国强制教育的一部分。但如何在各省份性别比例相差较大的情况下,更加有效的提高各省份小学教育资源配置效率是一个值得思考的问题。为了避免性别带来的影响,可以通过平行结构DEA模型根据学生性别分为两个平行子系统,来衡量我国2012~2018年各省份小学教育的资源配置情况。研究发现大部分省份小学教育资源配置的总系统效率未达到有效边界,仍有需要改进的地方。男学生在小学教育阶段的效率通常优于女学生在小学教育阶段的效率,但随着近些年我国教育体制的日益完善,女学生在小学教育阶段的效率呈上升趋势。此外,我国西部地区的小学教育资源配置效率在一些年份普遍优于东部和中部地区,而中部地区和东部地区小学教育总系统效率相对稳定,西部地区小学教育总系统效率波动较大。  相似文献   
22.
A rapid, sensitive and selective liquid chromatography–tandem mass spectrometry method for the detection of tandospirone (TDS) and its active metabolite 1‐[2‐pyrimidyl]‐piperazine (1‐PP) in Sprague–Dawley rat plasma is described. It was employed in a pharmacokinetic study. These analytes and the internal standards were extracted from plasma using protein precipitation with acetonitrile, then separated on a CAPCELL PAK ADME C18 column using a mobile phase of acetonitrile and 5 mm ammonium formate acidified with formic acid (0.1%, v/v) at a total flow rate of 0.4 mL/min. The detection was performed with a tandem mass spectrometer equipped with an electrospray ionization source. The method was validated to quantify the concentration ranges of 1.000–500.0 ng/mL for TDS and 10.00–500.0 ng/mL for 1‐PP. Total time for each chromatograph was 3.0 min. The intra‐day precision was between 1.42 and 6.69% and the accuracy ranged from 95.74 to 110.18% for all analytes. Inter‐day precision and accuracy ranged from 2.47 to 6.02% and from 98.37 to 105.62%, respectively. The lower limits of quantification were 1.000 ng/mL for TDS and 10.00 ng/mL for 1‐PP. This method provided a fast, sensitive and selective analytical tool for quantification of tandospirone and its metabolite 1‐PP in plasma necessary for the pharmacokinetic investigation.  相似文献   
23.
It was evaluated the effects of maternal treatment with the Trichilia catigua (ExTc) crude extract on the antibodies’ production by their offspring. Female rats received ExTc or saline from the first day of pregnancy until the twenty-first day after the birth of the pups, when the pups were weaned. All pups were inoculated with two doses of 50 μg of IgY diluted in aluminium hydroxide/PBS on days 26 and 40 of life. Antibody levels were analysed by ELISA. Our results show an increase in levels of IgG1 and IgG2a anti-IgY in female offspring of mothers treated with ExTc compared to female offspring of untreated mothers. Furthermore, ExTc treatment suppressed the production of IgG2a anti-IgY antibodies in males. The data show that maternal exposure to ExTc can modulate the production of antibodies in the offspring.  相似文献   
24.
基于教学行为视角,依据课堂教学系统CPUP模型理论和课堂教学基元系统有效性评价量表,通过对24位男女化学教师的24节常态课堂中基元系统有效性进行对比分析。结果发现,男女教师的主要差别表现为:在"时间利用的合理性"和"匹配度"2个维度上,女教师显著高于男教师;在"教学行为链实施质量" 和"资源和技术的使用质量"2个维度上,男教师显著高于女教师;而在总分和"基元内容的合理性"维度上,2者不存在显著差异。  相似文献   
25.
英语语调性别差异的统计分析   总被引:1,自引:0,他引:1  
本文主要采用语料库语言学的研究方法,选取IViE语料库中英国剑桥地区6男6女共12位母语朗读者的不同句型的单句和段落朗读中的相关句型,从英语语调的核心声学参数调核音高入手,分析男女朗读者在5种不同句子类型(陈述句、陈述疑问句、一般疑问句、特殊疑问句和感叹句)上的异同。我们针对408句声音语料,利用先进的计算机语音分析软件获取研究数据,再通过严格的统计分析,以定量分析的方式考察英语不同句型的调核音高差异程度和调核音高的性别差异,分析英国英语语调在调核音高上的性别差异和特点。  相似文献   
26.
随着人们对宿主肠道菌群的日益关注,关于胆汁酸与肠道菌群之间复杂关系的研究也越来越多.因肠道组织结构的复杂性和肠道菌群分布差异性,不同肠段胆汁酸的分布、表达及其生物学功能仍有待进一步研究.本文采用基于超高效液相色谱-三重四极杆-质谱联用(UPLC-QqQ-MS)的靶向代谢组分析结合基于核磁共振(NMR)波谱的非靶向代谢组分析方法,通过比较不同性别C57BL/6小鼠肠道各区段胆汁酸及粪样代谢组的变化水平,发现雌、雄小鼠不同肠段中胆汁酸的分布各不相同.另外,肠道下段各胆汁酸的性别差异性更为明显,以盲肠的性别差异性最为显著,这可能与盲肠的菌群微生态更为丰富有关.该研究为不同性别模型小鼠胆汁酸的代谢表型及其与肠道菌群的相互作用提供了基础研究数据.  相似文献   
27.
A simple, rapid and sensitive ultra‐performance liquid chromatography–tandem mass spectrometry (UPLC‐MS/MS) method has been developed and validated for the determination of alosetron (ALO) in human plasma. The assay method involved solid‐phase extraction of ALO and ALO 13C‐d3 as internal standard (IS) on a LichroSep DVB‐HL (30 mg, 1 cm3) cartridge. The chromatography was performed on an Acquity UPLC BEH C18 (50 × 2.1 mm, 1.7 µm) column using acetonitrile and 2.0 mm ammonium formate, pH 3.0 adjusted with 0.1% formic acid (80:20, v/v) as the mobile phase in an isocratic mode. For quantitative analysis, the multiple reaction monitoring transitions studied were m/z 295.1/201.0 for ALO and m/z 299.1/205.1 for IS in the positive ionization mode. The method was validated over a concentration range of 0.01–10.0 ng/mL for ALO. Post‐column infusion experiment showed no positive or negative peaks in the elution range of the analyte and IS after injection of extracted blank plasma. The extent of ion‐suppression/enhancement, expressed as IS‐normalized matrix factor, varied from 0.96 to 1.04. The assay recovery was within 97–103% for ALO and IS. The method was successfully applied to support a bioequivalence study of 1.0 mg alosetron tablets in 28 healthy Indian male and female subjects. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
28.
Gender determination of the human remains can be very challenging, especially in the case of incomplete ones. Herein, we report a proof-of-concept experiment where the possibility of gender recognition using Raman spectroscopy of teeth is investigated. Raman spectra were recorded from male and female molars and premolars on two distinct sites, tooth apex and anatomical neck. Recorded spectra were sorted into suitable datasets and initially analyzed with principal component analysis, which showed a distinction between spectra of male and female teeth. Then, reduced datasets with scores of the first 20 principal components were formed and two classification algorithms, support vector machine and artificial neural networks, were applied to form classification models for gender recognition. The obtained results showed that gender recognition with Raman spectra of teeth is possible but strongly depends both on the tooth type and spectrum recording site. The difference in classification accuracy between different tooth types and recording sites are discussed in terms of the molecular structure difference caused by the influence of masticatory loading or gender-dependent life events.  相似文献   
29.
Isradipine could be used for the treatment of high blood pressure or Parkinsonism, yet the study on pharmacokinetics (PK) of isradipine is lacking in the Chinese population. The current study aims to assess the dose proportionality, pharmacokinetics and gender effect of isradipine following oral single and multiple doses in Chinese subjects. A randomized, open‐label, parallel‐group trial was conducted in 30 healthy Chinese volunteers. Subjects randomly received a single dose of 2.5, 5 or 10 mg, and multiple doses (2.5 mg) of isradipine. Blood samples were collected pre‐dose (0 h) and 0.33, 0.67, 1, 1.5, 2, 3, 4, 6, 9, 12, 24, 36 and 48 h post‐dose. Isradipine was rapidly absorbed with the time to maximum concentration <1.27 h for all dosage groups. The maximum concentrations were 2.46, 5.34, 10.93 and 3.32 ng/mL and area under the concentration–time curve from time zero to the last time point (AUClast) were 7.05, 12.58, 24.68 and 5.31 ng/ml·h for the 2.5, 5 and 10 mg single‐dose and 2.5 mg multiple‐dose groups, respectively. The half‐life ranged from 5.76 to 7.94 h. The maximum concentration and AUC were found to increase linearly and dose‐dependently for isradipine. No statistical gender differences were found. These findings indicated that the pharmacokinetic parameters of isradipine in Chinese population were dose‐proportional and predictable over a range of 2.5–10 mg isradipine oral doses. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
30.
In this article a pattern arising from the coefficients in the expansion of the sum of the ?th powers of the roots of a quadratic equation is explored by computer. The paper is presented in the form of a correspondence on this problem, which originated during the Computer Appreciation Course held in University College, Galway, in July 1971, for teachers of mathematics for sixth forms. It is felt that the use of the conversational mode may emphasize some of the points of educational interest which arise in the elementary FORTRAN IV programs which are used to generate the array of coefficients. Two methods are adopted: the first involving a direct calculation using binomial coefficients and the second utilizing a recurrence relation. The programs are deliberately unsophisticated so that the educational aspects of the comparison of the methods may be high‐lighted.  相似文献   
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