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11.
Given a variety we study the existence of a class such that S1 every A can be represented as a global subdirect product with factors in and S2 every non-trivial A is globally indecomposable. We show that the following varieties (and its subvarieties) have a class satisfying properties S1 and S2: p-algebras, distributive double p-algebras of a finite range, semisimple varieties of lattice expansions such that the simple members form a universal class (bounded distributive lattices, De Morgan algebras, etc) and arithmetical varieties in which the finitely subdirectly irreducible algebras form a universal class (f-rings, vector groups, Wajsberg algebras, discriminator varieties, Heyting algebras, etc). As an application we obtain results analogous to that of Nachbin saying that if every chain of prime filters of a bounded distributive lattice has at most length 1, then the lattice is Boolean.We wish to thank Lic. Alfredo Guerin and Dr. Daniel Penazzi for helping us with linguistics aspects. We are indebted to the referee for several helpful suggestions. We also wish to thank Professor Mick Adams for providing us with several reprints and useful e-mail information on the subject.Suported by CONICOR and SECyT (UNC).  相似文献   
12.
There are approximately one million cases oftype 1 diabetes in the US, and the incidenceis increasing worldwide. Given that two-thirdsof cases present in childhood, it is criticalthat prediction and prevention research involvechildren. In this article, I examine whethercurrent research methodologies conform to theethical guidelines enumerated by the NationalCommission for the Protection of Human Subjectsof Biomedical and Behavioral Research, andadopted into the federal regulations thatprotect research subjects. I then offer twopolicy recommendations to help researchersdesign studies that conform to these ethicalrequirements.  相似文献   
13.
中国领导干部人格类型研究   总被引:15,自引:2,他引:15  
敖小兰 《心理科学》2004,27(3):731-734
该文用MBTI中文修订版对中国东部、中部、西部共745名领导干部进行测试,得出了我国领导干部人格类型的总体分布情况,以及不同性别、不同年龄、职务级别、单位性质、工作属地、学历的领导干部在16种人格类型上的分类:我国领导干部人格类型以ESFJ(外向感觉情感判断)类型居多,其次为ESFJ(外向感觉思维判断)类型,并且更多地偏向“S”(感觉)、“F”(情感)和“J”(判断)。  相似文献   
14.
阻塞性睡眠呼吸暂停综合征(obstructive sleep apnea hypopnea syndrome,OSAHS)是一种常见的睡眠呼吸紊乱性疾病,以睡眠时反复发作的上气道部分或完全阻塞为特征。近年发现OSAHS与2型糖尿病之间有着明显的相关性,二者均为心血管疾病的高危因素,合并存在能够严重影响生命质量与预期寿命...  相似文献   
15.
研究目的是探索中国背景下国有企业、民营企业、外资企业、政府机关四类组织中员工建言行为的差异,及员工个人权力感和权力动机的中介作用。采用问卷法对员工和管理者进行配对取样调查,通过对回收的324份有效问卷进行数据分析。结果表明,员工建言行为在四种组织类型中存在显著性差异,而员工个人权力感和权力动机在其中起到中介作用。此外,研究还发现,权力距离倾向在组织类型和个人权力感之间起到调节作用。最后,研究梳理了组织类型与建言行为的关系模型,并对未来研究做了展望。  相似文献   
16.
This research describes and evaluates a workshop aimed at promoting career specialty choice and examines relationships between measured career specialty interests, work values, and personality type. Three consecutive classes of second-year medical students (N = 161) participated in a two-session specialty choice workshop. All participants in the study rated the usefulness of the workshop and reported their level of specialty choice certainty and satisfaction. They also responded to measures of medical specialty preference, work values, and personality type. Results indicated two distinct student subgroups of career-specialty-decided and -undecided students. The former subgroup evidenced more stability and certainty of specialty choice as well satisfaction with their choice. Both groups of students reported having benefited from the workshop. Significant gender differences in the relationships between scores on a measure of medical specialty preference and scores on measures of work values and personality emerged. Implications are discussed in terms of the differential career counseling needs of students either decided or undecided about their career specialty choices.  相似文献   
17.
This paper aims at creating an adequate theoretical basis for a systematic integration of institutional insights into the pragma-dialectical analysis of argumentative exchanges that occur in institutionalised contexts. The argumentative practice of Prime Minister’s Question Time in the British House of Commons is examined, as a case in point, in order to illustrate how the knowledge of the characteristics of an institution, its rules and conventions can be integrated into the pragma-dialectical analysis. The paper highlights the role that theoretical concepts and tools such as strategic manoeuvring, argumentative activity types and dialectical profiles play in this integration.
Dima MohammedEmail:
  相似文献   
18.
张凤华  杨群  张庆林  汤永隆 《心理科学》2008,31(6):1461-1465
通过预备实验选取前件(或后件)是二元(或多元)的5种条件命题的4种推理形式作为实验材料,以大学本科生为被试,考察了五种不同条件命题类型对4种推理结果的影响.结果表明命题类型、推理规则以及两者的交互作用都非常显著.这个结果进一步验证了条件推理的集合映射模型.  相似文献   
19.
弗洛伊德认为道德产生于人的本能与现实之间的矛盾,良心是人自身反对自身的斗争,道德的产生意味着人自身的本能等感性力量得不到发展。良心的存在与维持,依赖于外在的权威力量的存在。弗洛伊德的超我是他律的内化这一道德模式的理想类型,是对此类道德模式的一种理论建构。  相似文献   
20.
This paper presents Automath encodings (which are also valid in LF/λP) of various kinds of foundations of mathematics. Then it compares these encodings according to their size, to find out which foundation is the simplest.

The systems analyzed in this way are two kinds of set theory (ZFC and NF), two systems based on Church's higher order logic (Isabelle/Pure and HOL), three kinds of type theory (the calculus of constructions, Luo's extended calculus of constructions, and Martin-Löf's predicative type theory) and one foundation based on category theory.

The conclusions of this paper are that the simplest system is type theory (the calculus of constructions), but that type theories that know about serious mathematics are not simple at all. In that case the set theories are the simplest. If one looks at the number of concepts needed to explain such a system, then higher order logic is the simplest, with twenty-five concepts. On the other side of the scale, category theory is relatively complex, as is Martin-Löf's type theory.

(The full Automath sources of the contexts described in this paper are one the web at http://www.cs.ru.nl/~freek/zfc-etc/.)  相似文献   

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