1,547 research outputs found
The Role for the Endocannabinoid System in Cardioprotection and Myocardial Adaptation
Results from different studies showing CB2 receptor-associated cardioprotective action are still fairly controversial and no single specific mechanism could be identified. Several groups investigated the involvement of the endocannabinoid system in cellular systems and function of cardiomyocytes, fibroblasts, macrophages and endothelial cells. While some studies are limited in their translational relevance, a few recent studies describe a myocardial ischemia and reperfusion scenario in a fashion comparable to the clinical situation. Recent studies provided evidence for involvement of the CB2 receptor–endocannabinoid axis in prevention of cardiomyocyte apoptosis including modulation of antioxidative enzymes and contractile elements expression. CB2 receptor has further been shown to specifically modulate the inflammatory response and macrophage function after myocardial ischemia. These effects have an impact on the subsequent myocardial remodeling, where the CB2 receptor modulates function of myofibroblasts, collagen production and limitation of myocardial infarction size. Recent experimental and clinical data showed the association of the endocannabinoid system in myocardial hypertrophy. In conclusion, increasing amount of evidence supports a crucial role of the endocannabinoid system in cardioprotection and myocardial remodeling, while some of them even suggest model-independent systemic effects in adaptation of cardiomyocytes or components of the extracellular matrix
Online User Assessment for Minimal Intervention During Task-Based Robotic Assistance
We propose a novel criterion for evaluating user input for human-robot
interfaces for known tasks. We use the mode insertion gradient (MIG)---a tool
from hybrid control theory---as a filtering criterion that instantaneously
assesses the impact of user actions on a dynamic system over a time window into
the future. As a result, the filter is permissive to many chosen strategies,
minimally engaging, and skill-sensitive---qualities desired when evaluating
human actions. Through a human study with 28 healthy volunteers, we show that
the criterion exhibits a low, but significant, negative correlation between
skill level, as estimated from task-specific measures in unassisted trials, and
the rate of controller intervention during assistance. Moreover, a MIG-based
filter can be utilized to create a shared control scheme for training or
assistance. In the human study, we observe a substantial training effect when
using a MIG-based filter to perform cart-pendulum inversion, particularly when
comparing improvement via the RMS error measure. Using simulation of a
controlled spring-loaded inverted pendulum (SLIP) as a test case, we observe
that the MIG criterion could be used for assistance to guarantee either task
completion or safety of a joint human-robot system, while maintaining the
system's flexibility with respect to user-chosen strategies.Comment: 10 page
G02-1466 Determining the Need to Fertilize Landscape Trees and Shrubs (Revised March 2004)
Most Nebraska soils are fertile enough to support tree and shrub growth without applying fertilizer. However, when woody plants exhibit poor growth or reduced vigor, yet have had adequate moisture and are not experiencing pest problems or other environmental limitations, the proper applicatin of fertilizer may be necessary. This NebGuide explains how to determine if fertilization of established trees and shrubs is required and how to apply the needed amount
Coulomb plasmas in outer envelopes of neutron stars
Outer envelopes of neutron stars consist mostly of fully ionized, strongly
coupled Coulomb plasmas characterized by typical densities about 10^4-10^{11}
g/cc and temperatures about 10^4-10^9 K. Many neutron stars possess magnetic
fields about 10^{11}-10^{14} G. Here we briefly review recent theoretical
advances which allow one to calculate thermodynamic functions and electron
transport coefficients for such plasmas with an accuracy required for
theoretical interpretation of observations.Comment: 4 pages, 2 figures, latex2e using cpp2e.cls (included). Proc. PNP-10
Workshop, Greifswald, Germany, 4-9 Sept. 2000. Accepted for publication in
Contrib. Plasma Phys. 41 (2001) no. 2-
Assessing a forestry education: The Northern Arizona University experience
In an attempt to provide students with a strong generalist education, the faculty at Northern Arizona University\u27s School of Forestry has presented its undergraduate forestry education in a unique, integrated, team-taught approach for over 20 years. Over this same period of time, higher education has experienced profound changes. Within the discipline, the technical knowledge expected of undergraduates has expanded greatly. Simultaneously the demand for accountability in higher education has increased. Students, parents, state legislators, governing boards, and taxpayers alike have questioned the importance, relevance, and value of higher education. The so-called student-as-consumer model in higher education is but one manifestation of this increased demand for accountability. A fundamental question arises: How well does the forestry program at NAU prepare students educationally as foresters? Assessing student academic achievement with respect to educational outcomes provides one way of answering this question. Such a process can help determine how well students master a set of defined skills, knowledges, and competencies. Such an approach requires a defined set of desired educational outcomes
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