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Yavorcik KJ, Reighard DA, Misra SP, Cotter LA, Cass SP, Wilson TD, Yates BJ. Effects of postural changes and removal of vestibular inputs on blood flow to and from the hindlimb of conscious felines. Am J Physiol Regul Integr Comp Physiol 297: R1777-R1784, 2009. First published September 30, 2009; doi: 10.1152/ajpregu.00551.2009.--Considerable data show that the vestibular system contributes to blood pressure regulation. Prior studies reported that lesions that eliminate inputs from the inner ears attenuate the vasoconstriction that ordinarily occurs in the hindlimbs of conscious cats during head-up rotations. These data led to the hypothesis that labyrinthine-deficient animals would experience considerable lower body blood pooling during head-up postural alterations. The present study tested this hypothesis by comparing blood flow though the femoral artery and vein of conscious cats during 20-60[degrees] head-up tilts from the prone position before and after removal of vestibular inputs. In vestibular-intact animals, venous return from the hindlimb dropped considerably at the onset of head-up tilts and, at 5 s after the initiation of 60[degrees] rotations, was 66% lower than when the animals were prone. However, after the animals were maintained in the head-up position for another 15 s, venous return was just 33% lower than before the tilt commenced. At the same time point, arterial inflow to the limb had decreased 32% from baseline, such that the decrease in blood flow out of the limb due to the force of gravity was precisely matched by a reduction in blood reaching the limb. After vestibular lesions, the decline in femoral artery blood flow that ordinarily occurs during head-up tlits was attenuated, such that more blood flowed into the leg. Contrary to expectations, in most animals, venous return was facilitated, such that no more blood accumulated in the hindlimb than when labyrinthine signals were present. These data show that peripheral blood pooling is unlikely to account for the fluctuations in blood pressure that can occur during postural changes of animals lacking inputs from the inner ear. Instead, alterations in total peripheral resistance following vestibular dysfunction could affect the regulation of blood pressure. blood flow patterning; venous return; cardiac output; orthostatic hypotension doi: 10.1152/ajpregu.00551.2009

Despite considerable interest in the neural mechanisms that regulate muscle blood flow, the descending pathways that control sympathetic outflow to skeletal muscles are not adequately understood. The present study mapped these pathways through the transneuronal transport of two recombinant strains of pseudorabies virus (PRV) injected into the gastrocnemius muscles in the left and right hindlimbs of rats: PRV-152 and PRV-BaBlu. To prevent PRV from being transmitted to the brain stem via motor circuitry, a spinal transection was performed just below the L2 level. Infected neurons were observed bilaterally in all of the areas of the brain that have previously been shown to contribute to regulating sympathetic outflow: the medullary raphe nuclei, rostral ventrolateral medulla (RVLM), rostral ventromedial medulla, A5 adrenergic cell group region, locus coeruleus, nucleus subcoeruleus, and the paraventricular nucleus of the hypothalamus. The RVLM, the brain stem region typically considered to play the largest role in regulating muscle blood flow, contained neurons infected following the shortest postinoculation survival times. Approximately half of the infected RVLM neurons were immunopositive for tyrosine hydroxylase, indicating that they were catecholaminergic. Many (47%) of the RVLM neurons were dually infected by the recombinants of PRV injected into the left and right hindlimb, suggesting that the central nervous system has a limited capacity to independently regulate blood flow to left and right hindlimb muscles. blood flow patterning; pseudorabies virus; exercise hyperemia

Karen Locke: Grounded Theory in Management Research 2001, London, Thousand Oaks, CA: Sage. 148 pages. In spite of the number of books available on the subject, 'grounded theory' is a [...]

Introduction. The aim of this paper is to explore the investigation of information-seeking behaviour in the literature of psychology, with special reference to the period before 1981, when the term was introduced into information science, and compare the research of that period, with research reported in 2022-2023. Method. A search of the literature for the term 'information-seeking behaviour' was carried out in Web of Science and Scopus for the period 1900 to 1980 and from January 2022 to May 2023, producing two data sets for analysis. Analysis. Descriptive analysis of sources and geographic distribution of the papers is presented. This is followed by an analysis of the research themes and approaches. Results. In the early set of papers the main context of the research was educational and career counselling and the main research perspective social learning theory, with an emphasis on the concept of locus of control. In the later set, the main theoretical interest was in aspects of cognition, with a particular interest in curiosity. Conclusion. There is much that the information science research can learn and apply from the literature of psychology. In particular, social learning theory, cognitive theory, and the associated research instruments could be of value. [ABSTRACT FROM AUTHOR]

Introduction. Activity theory, developed in the USSR as a Marxist alternative to Western psychology, has been applied widely in educational studies and increasingly in human-computer interaction research. Argument. The key elements of activity theory, Motivation, Goal, Activity, Tools, Object, Outcome, Rules, Community and Division of labour are all directly applicable to the conduct of information behaviour research. An activity-theoretical approach to information behaviour research would provide a sound basis for the elaboration of contextual issues, for the discovering of organizational and other contradictions that affect information behaviour. It may be used to aid the design and analysis of investigations. Elaboration. The basic ideas of activity theory are outlined and an attempt is made to harmonize different perspectives. A contrast is made between an activity system perspective and an activity process perspective and a diagrammatic representation of the process perspective is offered. Conclusion. Activity theory is not a predictive theory but a conceptual framework within which different theoretical perspectives may be employed. Typically, it is suggested that several methods of data collection should be employed and that the time frame for investigation should be long enough for the full range of contextual issues to emerge. Activity theory offers not only a useful conceptual framework, but also a coherent terminology to be shared by researchers, and a rapidly developing body of literature in associated disciplines.

An introduction is presented in which author discusses articles on topics including focuses on Gillian Oliver and colleagues which present a review of the literature on data cultures, that is the contexts in which data are created, collected, managed, accessed, used and re-used.

Introduction. This paper reports on a study of e-books issues in academic libraries in two European countries representative of small language markets -- Sweden and Lithuania. Method. Questionnaire surveys, using the same instrument, were carried out in Swedish and Lithuanian academic libraries. Analysis. Quantitative analysis was performed using the descriptive statistics capability of SurveyMonkey. Results. The survey's results reveal some interesting similarities and differences in the two countries. Business models for e-book acquisition in both countries show similarities -- the most popular additional model is purchase for perpetual ownership. One significant difference is that some of the Lithuanian academic librarians appear to have less direct knowledge of e-book acquisition, relying upon the Lithuanian Research Library Consortium to effect licence agreements with publishers and aggregators. Another significant difference is that academic libraries in Lithuania have a higher degree of access to e-books in the national language than is the case in Sweden. Conclusion. The findings show that the factors driving adoption of e-books, is composed of somewhat different elements in the two countries. Swedish librarians regard the need to keep up with technology and access and availability as the two main forces driving adoption of e-books in academic libraries. Lithuanian librarians see economics as the mainfactor, together with technology and demand from students. [ABSTRACT FROM AUTHOR]