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981.
The authors examine the problems of ex-post evaluation of the benefits deriving from services provided by Government Laboratories. They concentrate on the difficulties of conducting meaningful ex-post studies since they feel that too many claims are made on the basis of inadequate, incomplete economic assessments using data that would not be substantiated if probed deeply. Their views are based on a review of nine years' practical evaluation experience.The paper defines three ways in which services/information sources can link up with intended recipients, and discusses the practical problems associated with assessing the impact of services in each case. These problems range from sampling errors and sample bias in questionnaire approaches, to limited respondent knowledge and perspective. Critical probing can overcome these difficulties in some, though not all, instances, since there are issues of principle that prohibit unique attribution of benefits to specific initiatives in many ex-post analyses. The use of cost recovery as a proxy measure of worth is reviewed.The authors point out that ex-ante appraisal of profits is not subject to the same constraints and avoids many of the pitfalls of ex-post evaluation. 相似文献
982.
Karen G. Hales 《CBE life sciences education》2013,12(4):604-605
This edited volume of essays presents a countermainstream view against genetic underpinnings for cancer, behavior, and psychiatric conditions.This edited volume is a project from the Council of Responsible Genetics, a private organization based in Cambridge, Massachusetts, whose mission, as stated on its website, includes as one of several goals to “expose oversimplified and distorted scientific claims regarding the role of genetics in human disease, development and behavior.” This book represents such an effort. Editors Krimsky and Gruber are chair and president/executive director, respectively, of the organization and appear to have solicited contributions to the book from affiliates and other colleagues. Fewer than half of the 16 chapters are written by active laboratory scientists, however, and as a result, the book suffers from arguments clouded by imprecise use of terminology and preconceptions about genes and their functions. One might consider this book, or parts thereof, for an advanced undergraduate genetics class in which positions counter to the mainstream scientific view are presented and evaluated, and in which students are challenged to critically assess the quality of support for all arguments.The general theme of this book is to question the role of genes (and reproducible molecular mechanisms, more broadly) in cancer, behavior, psychiatric disorders, evolution, and other phenomena. One chapter promotes the tissue organization field theory (TOFT) against the somatic mutation theory of cancer. TOFT was proposed by the chapter authors in 2011 (Soto and Sonnenschein, 2011 ) but has not found traction and has garnered little attention beyond an initial refutation (Vaux, 2011 ). The authors assert that cancer is a disease of development and tissue repair primarily from environmental exposures and independent of genetic changes. Most cancer researchers agree that environmental factors can trigger cell growth but that ensuing mutations complete the picture in the genesis of malignancies. This chapter would be a good starting point from which one could assign students to explore papers cited in the Cancer Genome Atlas database, a growing resource compiling cancer genome data and subsequent validation in other systems of the effects of mutations found. In another chapter, a nonscientist author asserts that “in only a small percentage of cases are genes notable contributors to breast cancer,” implying imprecisely that only rare inherited cancer predisposition is genetic, when in fact cancer stemming from somatic mutations is also gene based. To assert that cancer stems only from environmental effects, to the exclusion of genes, overlooks the intertwining of the two arenas—radiation induces somatic mutations, for example, and estrogen mimics trigger cell division, which sets the stage for additional new mutations during DNA replication.
Open in a separate windowOther sections of the book argue a lack of evidence for genetic influence on behaviors and psychiatric conditions. One chapter centers on several refuted ideas of biology and behavior (for example XYY and monoamine oxidase genotypes associated with aggression), with the intended implication that all other biological connections to behavior must be suspect. A chapter on autism accepts but downplays a partial role of genetics in the disorder, while emphasizing environmental exposures. Students exploring this topic could examine the growing literature on de novo mutations found in autism patients (Huguet et al., 2013 ), among other autism studies, to see how interlocking causes of the disorder might best explained by the available data. In the context of disorders such as schizophrenia, the book does not acknowledge or address the literature reporting genetic associations with psychiatric predispositions. In a troubling instance, a cited reference is misrepresented as refuting a genetic connection to schizophrenia; the reference in question (Collins et al., 2012 ) actually reports genome-wide association studies showing linkage of schizophrenia to particular loci (just not to the genes originally suspected). The same research group the previous month reported copy number variations associated with schizophrenia (Kirov et al., 2012 ), but this finding was not cited. Psychiatric genetics is a rich area for students to explore, and the contrarian viewpoint of the book can provide a starting point to trigger students’ delving into the literature.Genetic Explanations: Sense and Nonsense includes two chapters with assertions counter to the neo-Darwinian synthesis of evolution. One claims, fairly misleadingly, that “a growing number of evolutionary biologists … believe that macroevolution was the result of mechanisms other than natural selection.” Another states that “not genomic DNA but epigenetic environmental influences … overwhelmingly affect our health and well being.” The idea that gene regulation via environmental and epigenetic effects is somehow not reducible to genes (and that genes are therefore not central to evolution) would be an interesting subject for students to explore in the literature to see what the data actually support.This book is recommended only for use in advanced classes centered on weighing evidence and dissecting arguments in scientific controversies. The book''s countermainstream assertion of a lack of significant genetic connection to cancer, autism, schizophrenia, and other phenomena provides multiple opportunities for students to explore the scientific literature surrounding such genetic connections. 相似文献
983.
AbstractTo be successful, junior faculty must properly manage their time in the face of expanding responsibilities. One such responsibility is supervising undergraduate research projects. Student research projects (either single or multi-student) can be undertaken as a full-time summer experience, or as a part-time academic year commitment. With many potential undergraduate research formats, and with different types of students, junior faculty may find challenges in forming their research group, establishing a structure that promotes student productivity, picking an appropriate project, or in effectively mentoring their students. This article draws from the authors’ experiences to help junior faculty navigate these complexities so that all parties reap the benefits of undergraduate research in interdisciplinary mathematical disciplines. 相似文献
984.
Interface project II and Ontario's review of educational policy 总被引:1,自引:0,他引:1
985.
986.
987.
988.
Galef BG 《Learning & behavior》2004,32(1):53-61
I review literature on four different approaches to the study of traditions in animals: observation of free-living animals,
laboratory experiment, armchair analysis, and field experiment. Because, by definition, a tradition entails social learning
of some kind, it is difficult, perhaps impossible, to establish that a behavior is in fact traditional without knowledge of
how it develops. Observations of free-living animals often provide strong circumstantial evidence of a tradition. However,
even in the view of several researchers who have studied possibly traditional behaviors in natural populations, observation
alone has not proven sufficient to show that social learning contributes to development of behaviors of interest. The relevance
of laboratory experiments to the understanding of the development of behaviors in free-living animals is always open to challenge.
Armchair analyses of field data can produce interesting hypotheses but cannot test them. Field experiments to determine how
behaviors of interest develop in population members provide a promising way forward. 相似文献
989.
Marie S. Tisak Larry P. Nucci Amanda M. Jankowski 《Early education and development》1996,7(2):137-148
Preschool children's social interactions with teachers and peers were observed in the context of moral and prudential events. Twenty groups of children were observed during free play for a total of 164 hours (8 hours per each group). Four types of moral transgressions were observed: physical harm, psychological harm, property loss, and property damage. The majority of the moral transgressions pertained to physical harm and property loss. There were equal frequencies of both moral and prudential physical harm acts; Moral physical harm acts resulted in actual harm; whereas, prudential acts were only potentially harmful. Teachers responded differently to moral and prudential rule violations. Gender differences were noted with regard to instigator, victim teachers' responses, and victims' responses. 相似文献
990.
The level of serum cholesterol (Ch), serum-high density lipoprotein cholesterol (HDLc), serum-low density lipoprotein cholesterol
(LDLc), serum very low density lipoprotein cholesterol (VLDLc), Triglyceride (Tg), Apolipoprotein A-1, B and ratio of Apolipoprotein
A1/B were observed in 151 survivors of myocardial infarction in different age groups. A significant increase was found in
the level of triglyceride, LDLc, apolipoprotein-B and a significant decrease in apolipoprotein-A1 and the ratio of apolipoprotein
A1/B. No significant alteration was found in serum cholesterol, HDLc except in the age group of 31–40 years and 41–50 years
and VLDLc. Thus, serum Apo A-1 and Apo-B may be considerably better markers for coronary artery disease than traditional lipid
parameters. 相似文献