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Assessing the motivational effects of ethanol in mice using a discrete-trial current-intensity intracranial self-stimulation procedure.
BackgroundAlcohol (ethanol) produces both rewarding and aversive effects, and sensitivity to these effects is associated with risk for an alcohol use disorder (AUD). Measurement of these motivational effects in animal models is an important but challenging aspect of preclinical research into the neurobiology of AUD. Here, we evaluated whether a discrete-trial current-intensity intracranial self-stimulation (ICSS) procedure can be used to assess both reward-enhancing and aversive responses to ethanol in mice.MethodsMale and female C57BL/6J mice were surgically implanted with bipolar stimulating electrodes targeting the medial forebrain bundle and trained on a discrete-trial current-intensity ICSS procedure. Mice were tested for changes in response thresholds after various doses of ethanol (0.5âŻg/kg-1.75âŻg/kg; nâŻ=âŻ5-7 per dose), using a Latin square design.ResultsA 1âŻg/kg dose of ethanol produced a significant reward-enhancement (i.e., lowered response thresholds), whereas a 1.75âŻg/kg dose produced an aversive effect (elevated response thresholds). Ethanol doses from 1 to 1.75âŻg/kg increased response latencies as compared to saline treatment.ConclusionsThe discrete-trial current-intensity ICSS procedure is an effective assay for measuring both reward-enhancing responses to ethanol as well as aversive responses in the same animal. This should prove to be a useful tool for assessing the effects of experimental manipulations on the motivational effects of ethanol in mice
Importance of geometry of the extracellular matrix in endochondral bone differentiation.
Subcutaneous implantation of coarse powders (74-420 micron) of demineralized diaphyseal bone matrix resulted in the local differentiation of endochondral bone. However, implantation of matrix with particle size of 44-74 micron (Fine matrix) did not induce bone. We have recently reported that the dissociative extraction of coarse matrix with 4 M guanidine HCl resulted in a complete loss of the ability of matrix to induce endochondral bone; the total loss of biological activity could be restored by reconstitution of extracted soluble components with inactive residue. To determine the possible biochemical potential of fine matrix to induce bone, the matrix was extracted in 4 M guanidine HCl and the extract was reconstituted with biologically inactive 4 M guanidine HCl-treated coarse bone matrix residue. There was a complete restoration of the biological activity by the extract of fine matrix upon reconstitution with extracted coarse matrix. Polyacrylamide gel electrophoresis of the extract of fine matrix revealed similar protein profiles as seen for the extract of coarse matrix. Gel filtration of the 4 M guanidine HCl extract of fine powder on Sepharose CL-6B and the subsequent reconstitution of various column fractions with inactive coarse residue showed that fractions with proteins of 20,000-50,000 mol wt induced new bone formation. These observations demonstrate that although fine bone matrix contains, osteoinductive proteins, matrix geometry (size) is a critical factor in triggering the biochemical cascade of endochondral bone differentiation. Mixing of coarse matrix with Fine results in partial response and it was confined to areas in contact with coarse particles. The results imply a role for geometry of extracellular bone matrix in anchorage-dependent proliferation and differentiation of cells
Simulation of Steady Laser Hardening by an Arbitrary Lagrangian Eulerian Method
One of the most practical methods for simulation of steady state thermal processing is the Arbitrary Lagrangian-\ud
Eulerian method. Each calculation step is split into two phases. In the first phase, the Lagrangian phase, the element mesh\ud
remains attached to the material. The evolution of the state variables is monitored and the state at the end of the phase is\ud
calculated. In the second phase, the Eulerian phase, the mesh is, broadly speaking, restored to its original position with\ud
respect to a window attached to the moving heat source. The mesh is not restored to its exact original position, but some\ud
allowance is made perpendicular to the flow direction in order to capture movement of the free surfaces. In this paper a finite\ud
element model for Lagrangian simulation of thermo-mechanical processes with phase transformations is combined with a\ud
second order discontinuous Galerkin method for modeling of Eulerian advection
The importance of precautionary saving motive among Indonesian households
In the developing world, the population is frequently faced with numerous natural, economic, institutional and market risks. Because of these uncertainties, many individuals and households experience difficult periods of unexpected reduction in income. Using panel data from the Indonesian Family Life Survey (IFLS), this paper tests the existence of precautionary saving associated with income risk in Indonesia. The results of the estimation show that the uncertainty variable is not significantly related to the growth of consumption which signifies that Indonesian households do not constitute precautionary saving to smooth their consumption. The finding may be explained by the fact that Indonesian households have in their possession other type of support mechanisms based particularly on inter-generational and -communal solidarity.Uncertainty; Income Risks; Precautionary Savings
Estimation of household demand systems with theoretically compatible Engel curves and unit value specifications
We develop a method for estimation of price reactions using unit value
data which exploits the implicit links between quantity and unit value
choices. This allows us to combine appealing Engel curve specifications
with a model of unit value determination in a way which is consistent
with demand theory, unlike methods hitherto prominent in the literature.
The method is applied to Czech data
Spartan Daily, March 24, 1976
Volume 66, Issue 32https://scholarworks.sjsu.edu/spartandaily/6063/thumbnail.jp
Spartan Daily, March 25, 1976
Volume 66, Issue 33https://scholarworks.sjsu.edu/spartandaily/6064/thumbnail.jp
Alternative Asymptotics and the Partially Linear Model with Many Regressors
Non-standard distributional approximations have received considerable
attention in recent years. They often provide more accurate approximations in
small samples, and theoretical improvements in some cases. This paper shows
that the seemingly unrelated "many instruments asymptotics" and "small
bandwidth asymptotics" share a common structure, where the object determining
the limiting distribution is a V-statistic with a remainder that is an
asymptotically normal degenerate U-statistic. We illustrate how this general
structure can be used to derive new results by obtaining a new asymptotic
distribution of a series estimator of the partially linear model when the
number of terms in the series approximation possibly grows as fast as the
sample size, which we call "many terms asymptotics"
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