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1.
梁莉丹  林振浪  陈尚勤  赵凯怡  陈翔 《应用数学》2015,37(5):398-400,429
目的 探讨早期干预对极低出生体重早产儿智能发育的影响,为极低出生体重早产儿的早期干预提供依据。方法 239 例极低出生体重早产儿为早产随访组,采用鲍秀兰早期教育资料制定的干预计划,进行系统干预,并与326 例失访的早产儿童以及与随访组相似的326 例正常儿童进行对照分析。采用Gesell 儿童发育量表等标准化工具进行发育评估。结果 早产随访组Gesell 儿童发育量表5 项均分、总发育商(developmental quotient,DQ)总分与早产失访组相比差异均有统计学差异(均P<0.05)。结论 早期干预能显著促进极低出生体重早产儿的智能发育,提高患儿的生活质量。  相似文献   
2.
This paper provides a solution for the degenerate scale for N-gon configuration in antiplane elasticity using the conformal mapping function, and the lower and upper bounds for the degenerate scale for N = 3, 4, 5, 6, 7, 8, 10, 20, 30, 40, 50, 100, 150 and 200, are evaluated.  相似文献   
3.
The Italian health insurance market is currently undersized. The paucity of assured data and the discontinuous statistical surveys carried out by the National Institute of Statistics (ISTAT) represent one of the main obstacles to the insurance market development. The paper sets forth a parametric model to estimate technical basis for health insurance policies when data are limited and only aggregated information on mortality and morbidity is available. The probabilistic framework is based on a multiple state continuous and time inhomogeneous Markov model. We provide an estimate of transition intensities from the healthy state to the sickness state when only prevalence rates of sickness are available, according to an extension and modification of the methodology proposed in Olivieri (1996) for Long Term Care insurance. We assume that mortality intensity of both healthy and sick lives is modelled by two independent Gompertz–Makeham models.  相似文献   
4.
关于中学生的原子、分子心智模型的研究   总被引:2,自引:0,他引:2  
魏冰  贾玉江  潘海鸿  钱玲 《化学教育》2001,22(3):6-9,13
学生对于科学概念的认识被称为学生的心智模型。本研究探讨了学生关于原子、分子2个概念的心智模型。研究采用半结构的访谈法,访谈对象是初三、高一和大学一年级的学生。文章从2个方面对研究结果进行了分析:学生关于原子模型的认识、学生对于原子、分子的描述。文章最后对研究结果进行了讨论。  相似文献   
5.
液相色谱-串联质谱法同时检测饲料中7种精神类药物   总被引:1,自引:0,他引:1  
建立了液相色谱-串联质谱同时检测饲料样品中7种精神类药物(硝西泮、奥沙西泮、氯丙嗪、异丙嗪、地西泮、奋乃静、硫利达嗪)的方法.通过对提取溶剂、净化等预处理条件及LC-MS/MS 分析条件的优化,可以同时检测饲料中7种违禁精神类药物.饲料样品经乙腈/水(9:1, V/V)提取后,过MCX固相萃取柱净化,氮吹至干,用1 mL乙腈/水(2:8, V/V)溶解后测定,采用SRM模式进行定性与定量分析.7种精神类药物在饲料中的回收率为53.9%~110.2%; 相对标准偏差为3.4%~18.4%;硝西泮、奥沙西泮、氯丙嗪、异丙嗪的检出限为1.0 ng/g;对地西泮、奋乃静、硫利达嗪的检出限为5.0 ng/g.结果表明,本方法可用于饲料中7种精神类药物的测定.  相似文献   
6.
We report a case study that explored how three college students mentally represented the knowledge they held of inferential statistics, how this knowledge was connected, and how it was applied in two problem solving situations. A concept map task and two problem categorization tasks were used along with interviews to gather the data. We found that the students’ representations were based on incomplete statistical understanding. Although they grasped various concepts and inferential tests, the students rarely linked key concepts together or to tests nor did they accurately apply that knowledge to categorize word problems. We suggest that one reason the students had difficulty applying their knowledge is that it was not sufficiently integrated. In addition, we found that varying the instruction for the categorization task elicited different mental representations. One instruction was particularly effective in revealing students’ partial understandings. This finding suggests that modifying the task format as we have done could be a useful diagnostic tool.  相似文献   
7.
Two studies investigated how decision makers characterize alternatives in important real-life decisions, which they themselves had made (to leave a partner, to choose an education and to choose a home). First, the participants indicated a very high degree of involvement in the decisions studied and about half of the participants gave maximum involvement ratings for the partner decision. Second, the results showed that concepts that are essential in most decision theories, such as, consequence, probability and value were important characteristics of the decisions. Third, emotion, positive and negative affect were also important characteristics. Fourth, value and emotion were uncorrelated. Fifth, the patterns of characteristics of decisions made in the past did not differ markedly from the characteristics given to future decisions. Principal component analyses were performed on the ratings of applicability of the different characteristics across participants for each decision situation. Three factors were extracted. There was one factor for positive affect/emotions and another factor for negative affect/emotions verified in oblique solutions. Thus, different scales are needed to represent emotion/affect components (and not bipolar scales) in real-life important decisions. The third factor represented the way in which a decision was represented (moving pictures dialogue etc.). An analysis restricted to the participants who rated 100% involvement showed an additional fourth factor with “what others would think”, “similar situations”, “values” and “money” as the most prominent characteristics. This points to the importance of controlling for participant involvement in studies of human decision making to enable generalizations to real-life decisions.  相似文献   
8.
The relationship between mental computation and number sense is complex: mental computation can facilitate number sense when students are encouraged to be flexible, but flexibility and number sense is neither sufficient nor necessary for accuracy in mental computation. It is possible for familiarity with a strategy to compensate for a lack of number sense and inefficient processes. This study reports on six case studies exploring Year 3 students’ procedures for and understanding of mental addition and subtraction, and understanding of number sense and other cognitive, metacognitive, and affective factors associated with mental computation. The case studies indicate that the mental computation process is composed of four stages in which cognitive, metacognitive and affective factors operate differently for flexible and inflexible computers. The authors propose a model in which the differences between computer types are seen in terms of the application of different knowledges in number facts, numeration, effect of operation on number, and beliefs and metacognition on strategy choice and strategy implementation.  相似文献   
9.
微量元素与精神病的研究   总被引:2,自引:0,他引:2  
一些基础医学实验研究和临床观察的资料表明,精神疾病患者体内的微量元素存在着显著的异常,已引起了国内外学者广泛关注,本文根据近年来的国内外文献报道,概述了微量元素锌(Zn),铜(Cu),铁(Fe)和常量元素钙(Ca),镁(Mg)的生理作用及与精神病关系的研究进展。  相似文献   
10.
This paper studies a consumption–investment problem involving health shock risk, perishable consumption, and consumption of housing services. Additionally to a risk-free asset and a stock index, the agent can invest in real estate. I analyze the impact of health shocks on the optimal consumption and investment decisions in model specifications with and without the possibility to buy critical illness insurance. I discuss the influence of critical illness insurance on the optimal strategy and analyze the drivers of the optimal critical illness insurance demand. The results indicate that health shock risk has potentially devastating consequences, especially for young agents. It turns out that critical illness insurance is an excellent instrument for hedging health shock risk and for consumption smoothing across different health states. Optimal critical illness insurance demand is decreasing in financial wealth and increasing in human wealth. Real estate prices have a minor influence on optimal critical illness insurance demand.  相似文献   
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