Improvement in laboratory research: Effects of stocking density, variation and sample size on outcomes of growth studies with shrimp

In the course of fine structure studies of spontaneous “C-type” particle production in a viper (Vipera russelli) spleen cell line, designated VSW, virus particles were frequently observed within mitochondria. The latter were usually enlarged or swollen, compared to virus-free mitochondria, and displayed a considerable degree of cristae disorganization.Intramitochondrial viruses measure 90 to 100 mμ in diameter, and consist of a nucleoid or core region of varying density and measuring approximately 45 mμ in diameter. Nucleoid density variation is presumed to reflect varying degrees of condensation, and hence maturation stages. The core region is surrounded by a less-dense outer zone presumably representing viral capsid.Particles are usually situated in peripheral regions of the mitochondrion. In most instances they appear to be lodged between loosely apposed inner and outer mitochondrial membranes.

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The Proportional Closeness and the Expected Sample Size of Sequential Procedures for Estimating Tail Probabilities in Exponential Distributions

Communications in Statistics - Simulation and Computation ◽

10.1080/03610917408548333 ◽

1974 ◽

Vol 3 (2) ◽

pp. 105-120

Author(s):

S. Zacks

Keyword(s):

Sample Size ◽

Tail Probabilities ◽

Exponential Distributions ◽

Expected Sample Size ◽

Sequential Procedures

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A conservative Sample size for the comparison of several proportions

Communication in Statistics- Theory and Methods ◽

10.1080/03610927808827712 ◽

1978 ◽

Vol 7 (13) ◽

pp. 1283-1293

Author(s):

A.I. Khuri

Keyword(s):

Sample Size

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The Role of Distress Disclosure Tendencies in the Experience and Expression of Laboratory-Induced Sadness

Journal of Individual Differences ◽

10.1027/1614-0001/a000222 ◽

2017 ◽

Vol 38 (1) ◽

pp. 55-62 ◽

Cited By ~ 1

Author(s):

Jeffrey H. Kahn ◽

Daniel W. Cox ◽

A. Myfanwy Bakker ◽

Julia I. O’Loughlin ◽

Agnieszka M. Kotlarczyk

Keyword(s):

Individual Differences ◽

Emotional Reactivity ◽

Subjective Experience ◽

Negative Emotion ◽

Theoretical Models ◽

Laboratory Research ◽

Emotion Words ◽

Distress Disclosure ◽

Computerized Text Analysis

Abstract. The benefits of talking with others about unpleasant emotions have been thoroughly investigated, but individual differences in distress disclosure tendencies have not been adequately integrated within theoretical models of emotion. The purpose of this laboratory research was to determine whether distress disclosure tendencies stem from differences in emotional reactivity or differences in emotion regulation. After completing measures of distress disclosure tendencies, social desirability, and positive and negative affect, 84 participants (74% women) were video recorded while viewing a sadness-inducing film clip. Participants completed post-film measures of affect and were then interviewed about their reactions to the film; these interviews were audio recorded for later coding and computerized text analysis. Distress disclosure tendencies were not predictive of the subjective experience of emotion, but they were positively related to facial expressions of sadness and happiness. Distress disclosure tendencies also predicted judges’ ratings of the verbal disclosure of emotion during the interview, but self-reported disclosure and use of positive and negative emotion words were not associated with distress disclosure tendencies. The authors present implications of this research for integrating individual differences in distress disclosure with models of emotion.

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Behavioral Testing of Mice Concerning Anxiety and Depression

Zeitschrift für Psychologie ◽

10.1027/2151-2604/a000215 ◽

2015 ◽

Vol 223 (3) ◽

pp. 151-156 ◽

Cited By ~ 1

Author(s):

Nina Schweinfurth ◽

Undine E. Lang

Keyword(s):

Environmental Influences ◽

Sickness Behavior ◽

Laboratory Research ◽

Anxiety And Depression ◽

Housing Conditions ◽

Human Beings ◽

Behavioral Testing ◽

New Developments ◽

Animal Trials ◽

Resilience Factors

Abstract. In the development of new psychiatric drugs and the exploration of their efficacy, behavioral testing in mice has always shown to be an inevitable procedure. By studying the behavior of mice, diverse pathophysiological processes leading to depression, anxiety, and sickness behavior have been revealed. Moreover, laboratory research in animals increased at least the knowledge about the involvement of a multitude of genes in anxiety and depression. However, multiple new possibilities to study human behavior have been developed recently and improved and enable a direct acquisition of human epigenetic, imaging, and neurotransmission data on psychiatric pathologies. In human beings, the high influence of environmental and resilience factors gained scientific importance during the last years as the search for key genes in the development of affective and anxiety disorders has not been successful. However, environmental influences in human beings themselves might be better understood and controllable than in mice, where environmental influences might be as complex and subtle. The increasing possibilities in clinical research and the knowledge about the complexity of environmental influences and interferences in animal trials, which had been underestimated yet, question more and more to what extent findings from laboratory animal research translate to human conditions. However, new developments in behavioral testing of mice involve the animals’ welfare and show that housing conditions of laboratory mice can be markedly improved without affecting the standardization of results.

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