95,622 research outputs found
When does centrality matter? Scientific productivity and the moderating role of research specialization and cross-community ties
The present study addresses the ongoing debate concerning academic scientific productivity. Specifically, given the increasing number of collaborations in academia and the crucial role networks play in knowledge creation, we investigate the extent to which building social capital within the academic community represents a valuable resource for a scientist's knowledge-creation process. We measure the social capital in terms of structural position within the academic collaborative network. Furthermore, we analyse the extent to which an academic scientist's research specialization and ties that cross-community boundaries act as moderators of the aforementioned relationship. Empirical results derived from an analysis of an Italian academic community from 2001 to 2008 suggest academic scientists that build social capital by occupying central positions in the community outperform their more isolated colleagues. However, scientific productivity declines beyond a certain threshold value of centrality, hence revealing the existence of an inverted U-shaped relationship. This relationship is negatively moderated by the extent to which an academic focuses research activities in few scientific knowledge domains, whereas it is positively moderated by the number of cross-community ties established
Alcohol representations are socially situated: an investigation of beverage representations by using a property generation task
Previous research suggests that people's representations of alcoholic beverages play an important role in drinking behavior. However, relatively little is known about the contents of these representations. Here, we introduce the property generation task as a tool to explore these representations in detail. In a laboratory study (N = 110), and a bar field-study (N = 56), participants listed typical properties of alcoholic beverages, sugary beverages, and water. Each of these properties was then categorized using a previously developed, hierarchical coding scheme. For example, the property âsweetâ was categorized as referring to âtasteâ, which falls under âsensory experienceâ, which falls under âconsumption situationâ. Afterwards, participants completed measures of drinking behavior and alcohol craving. Results showed that alcoholic beverages were strongly represented in terms of consumption situations, with 57% and 69% of properties relating to consumption in the laboratory and the bar study, respectively. Specifically, alcoholic beverages were more strongly represented in terms of the social context of consumption (e.g., âwith friendsâ) than the other beverages. In addition, alcoholic beverages were strongly represented in terms of sensory experiences (e.g. âsweetâ) and positive outcomes (e.g. âcreates funâ), as were the sugary beverages and water. In Study 1, the extent to which alcoholic beverages were represented in terms of social context was positively associated with craving and regularly consuming alcohol. The property generation task provides a useful tool to access people's idiosyncratic representations of alcoholic beverages. This may further our understanding of drinking behavior, and help to tailor research and interventions to reduce drinking of alcoholic and other high-calorie beverages
On Causal Relations between Mental Organizer, Action under Mental Processes, and Social Environment
The purpose of the research was to study the relationships
between mental organizers, action under mental process, and social
environment through observation. A category system for each
behavior was constructed and data were analyzed with matrices to
find out kinds of root causes in causal dynamic. Reliability,
subjectivity, and validity of observation were assessed. The
coefficient of reliability was 0.937. The observation had about 11%
subjectivity, and the frequencies were in the categories where they
should be, mainly. Results indicate that there occurs causal
variety. The causes are not stable. As an entity, the results show
that it is possible to tackle mind processes through the causation.
Furthermore, the processes are in series but they drop by in a
parallel mode when the task becomes more difficult. However, the
mindamic seems to have the greatest possible number of the degrees
of freedom, simultaneously
What the eye does not see: visualizations strategies for the data collection of personal networks
The graphic representation of relational data is one of the central elements of social network analysis. In this paper, the author describe
the use of visualization in interview-based data collection procedures
designed to obtain personal networks information, exploring four
main contributions. First, the author shows a procedure by which the
visualization is integrated with traditional name generators to facilitate obtaining information and reducing the burden of the interview
process. Second, the author describes the reactions and qualitative
interpretation of the interviewees when they are presented with an
analytical visualization of their personal network. The most frequent
strategies consist in identifying the key individuals, dividing the personal network in groups and classifying alters in concentric circles
of relative importance. Next, the author explores how the visualization of groups in personal networks facilitates the enumeration of the
communities in which individuals participate. This allows the author
to reflect on the role of social circles in determining the structure of
personal networks. Finally, the author compares the graphic representation obtained through spontaneous, hand-drawn sociograms
with the analytical visualizations elicited through software tools. This
allows the author to demonstrate that analytical procedures reveal
aspects of the structure of personal networks that respondents are
not aware of, as well as the advantages and disadvantages of using
both modes of data collection. For this, the author presents findings
from a study of highly skilled migrants living in Spain (n = 95) through
which the author illustrates the challenges, in terms of data reliability,
validity and burden on both the researcher and the participants
Contrasting alterations to synaptic and intrinsic properties in upper-cervical superficial dorsal horn neurons following acute neck muscle inflammation
Background:
Acute and chronic pain in axial structures, like the back and neck, are difficult to treat, and have incidence as high as 15%. Surprisingly, most preclinical work on pain mechanisms focuses on cutaneous structures in the limbs and animal models of axial pain are not widely available. Accordingly, we developed a mouse model of acute cervical muscle inflammation and assessed the functional properties of superficial dorsal horn (SDH) neurons.<p></p>
Results:
Male C57/Bl6 mice (P24-P40) were deeply anaesthetised (urethane 2.2?g/kg i.p) and the rectus capitis major muscle (RCM) injected with 40??l of 2% carrageenan. Sham animals received vehicle injection and controls remained anaesthetised for 2?hrs. Mice in each group were sacrificed at 2?hrs for analysis. c-Fos staining was used to determine the location of activated neurons. c-Fos labelling in carrageenan-injected mice was concentrated within ipsilateral (87% and 63% of labelled neurons in C1 and C2 segments, respectively) and contralateral laminae I - II with some expression in lateral lamina V. c-Fos expression remained below detectable levels in control and sham animals. In additional experiments, whole cell recordings were obtained from visualised SDH neurons in transverse slices in the ipsilateral C1 and C2 spinal segments. Resting membrane potential and input resistance were not altered. Mean spontaneous EPSC amplitude was reduced by ~20% in neurons from carrageenan-injected mice versus control and sham animals (20.63???1.05 vs. 24.64???0.91 and 25.87???1.32 pA, respectively). The amplitude (238???33 vs. 494???96 and 593???167 pA) and inactivation time constant (12.9???1.5 vs. 22.1???3.6 and 15.3???1.4?ms) of the rapid A type potassium current (IAr), the dominant subthreshold current in SDH neurons, were reduced in carrageenan-injected mice.<p></p>
Conclusions:
Excitatory synaptic drive onto, and important intrinsic properties (i.e., IAr) within SDH neurons are reduced two hours after acute muscle inflammation. We propose this time point represents an important transition period between peripheral and central sensitisation with reduced excitatory drive providing an initial neuroprotective mechanism during the early stages of the progression towards central sensitisation
Entrepreneurship as nexus of change: the syncretistic production of the future
This paper deals with the issue of how the future is created and the mechanisms through which it is produced and conceived. Key to this process appears to be social interaction and how it is used to bring about change. Examining the entrepreneurial context by qualitative longitudinal research techniques, the study considers the situations of three entrepreneurs. It demonstrates that the web of relationships in which individuals are engaged provide the opportunity to enact the environment in new ways, thus producing organizations for the future. It further provides empirical evidence for a Heideggerian reading of strategy-as-practice, extending this conceptualization to account for the temporal dimension
Epigenetic inheritance. Concepts, mechanisms and perspectives
Parents' stressful experiences can influence an offspring's vulnerability to many pathological conditions, including psychopathologies, and their effects may even endure for several generations. Nevertheless, the cause of this phenomenon has not been determined, and only recently have scientists turned to epigenetics to answer this question. There is extensive literature on epigenetics, but no consensus exists with regard to how and what can (and must) be considered to study and define epigenetics processes and their inheritance. In this work, we aimed to clarify and systematize these concepts. To this end, we analyzed the dynamics of epigenetic changes over time in detail and defined three types of epigenetics: a direct form of epigenetics (DE) and two indirect epigenetic processes-within (WIE) and across (AIE). DE refers to changes that occur in the lifespan of an individual, due to direct experiences with his environment. WIE concerns changes that occur inside of the womb, due to events during gestation. Finally, AIE defines changes that affect the individual's predecessors (parents, grandparents, etc.), due to events that occur even long before conception and that are somehow (e.g., through gametes, the intrauterine environment setting) transmitted across generations. This distinction allows us to organize the main body of epigenetic evidence according to these categories and then focus on the latter (AIE), referring to it as a faster route of informational transmission across generations-compared with genetic inheritance-that guides human evolution in a Lamarckian (i.e., experience-dependent) manner. Of the molecular processes that are implicated in this phenomenon, well-known (methylation) and novel (non-coding RNA, ncRNA) regulatory mechanisms are converging. Our discussion of the chief methods that are used to study epigenetic inheritance highlights the most compelling technical and theoretical problems of this discipline. Experimental suggestions to expand this field are provided, and their practical and ethical implications are discussed extensivel
Sensorimotor Laws, Mechanisms, and Representations
According to the sensorimotor account, vision does not imply theconstruction of internally generated representations of the environment, butit isthe skillful exercise of the sensorimotor contingencies obeying sense-specific laws. In this short study, I focus on the notion of âsensorimotor lawâ and characterize the kind of explanation providedby the sensorimotor theory as a form of covering law model. I then question the nature of such sensorimotor laws and describe them as mechanisms. I show that a mechanistic interpretation provides a better account of the sensorimotor invariances, which fosters us to rebalance the explanatory burden of sensorimotor action and information. Finally, I show that the question of the roleof representations within the sensorimotor theory should be reconsidered
Purifying Selection in Deeply Conserved Human Enhancers Is More Consistent than in Coding Sequences
(c) 2014 De Silva et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
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