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Silicon compilation
Silicon compilation is a term used for many different purposes. In this paper we define silicon compilation as a mapping from some higher level description into layout. We define the basic issues in structural and behavioral silicon compilation and some possible solutions to those issues. Finally, we define the concept of an intelligent silicon compiler in which the compiler evaluates the quality of the generated design and attempts to improve it if it is not satisfactory
Evidence for Broad Versus Segregated Projections from Cholinergic and Noradrenergic Nuclei to Functionally and Anatomically Discrete Subregions of Prefrontal Cortex
The prefrontal cortex (PFC) is implicated in a variety of cognitive and executive operations. However, this region is not a single functional unit; rather, it is composed of several functionally and anatomically distinct networks, including anterior cingulate cortex (ACC), medial prefrontal cortex (mPFC), and orbitofrontal cortex (OFC). These prefrontal subregions serve dissociable behavioral functions, and are unique in their afferent and efferent connections. Each of these subregions is innervated by ascending cholinergic and noradrenergic systems, each of which likewise has a distinct role in cognitive function; yet the distribution and projection patterns of cells in the source nuclei for these pathways have not been examined in great detail. In this study, fluorescent retrograde tracers were injected into ACC, mPFC, and OFC, and labeled cells were identified in the cholinergic nucleus basalis of Meynert (NBM) and noradrenergic nucleus locus coeruleus (LC). Injections into all three cortical regions consistently labeled cells primarily ipsilateral to the injection site with a minimal contralateral component. In NBM, retrogradely labeled neurons were scattered throughout the rostral half of the nucleus, whereas those in LC tended to cluster in the core of the nucleus, and were rarely localized within the rostral or caudal poles. In NBM, more than half of all retrogradely labeled cells possessed axon collaterals projecting two or more PFC subregions. In LC, however, only 4.3% of retrogradely labeled neurons possessed collaterals targeting any two prefrontal subregions simultaneously, and no cells were identified that projected to all three regions. Of all labeled LC neurons, 49.3% projected only to mPFC, 28.5% projected only to OFC, and 18.0% projected only to ACC. These findings suggest that subsets of LC neurons may be capable of modulating neuronal activity in individual prefrontal subregions independently, whereas assemblies of NBM cells may exert a more unified influence on the three areas, simultaneously. This work emphasizes unique aspects of the cholinergic and noradrenergic projections to functionally and anatomically distinct subregions of PFC and provides insights regarding global versus segregated regulation of prefrontal operations by these neuromodulatory pathways
Chapter 2.2: 3-D Topo Surface Visualization of Metal Ion Anti-Buffering: An Unexpected Behavior in Metal–Ligand Complexation Systems
Diluting a system that contains metal complexes can sometimes cause surprises. This chapter describes “metal ion anti-buffering”, a situation in which free metal ion concentrations rapidly increase as system dilution drives dissociation. It only occurs under excess free ligand conditions when a solution is dominated by higher stoichiometry complexes. The Law of Mass Action is used to provide a mathematical justification for the phenomenon. A Cu2+-ethylenediamine mixture exhibits this phenomenon when excess free ethylenediamine (en) is present. For example, it occurs when diluting a solution containing a four-fold excess of en over Cu2+. As this mixture is diluted by a factor of ~5600, the modeled free Cu2+ concentration shows a ~470-fold increase. Taken together, this is 2.5 million times higher than dilution of the system would yield in other circumstances. Included are experimental data confirming anti-buffering in the Cu2+-en system. Many other metal-ligand systems can display this behavior. Four additional examples are illustrated including an amino acid under physiological pHs. Anti-Buffering TOPOS, a downloadable Excel workbook in a supplemental file, allows readers to simulate this behavior for many metal-ligand systems. A PowerPoint lecture and teaching materials are also provided, suitable for inclusion in upper division and graduate courses in analytical chemistry, biochemistry and geochemistry.https://scholarworks.umt.edu/topos/1005/thumbnail.jp
SHORT-RUN DEMAND RELATIONSHIPS IN THE U.S. FATS AND OILS COMPLEX
Fats and oils play a prominent role in U.S. dietary patterns. Recent concerns over the negative health consequences associated with fats and oils have led many to suspect structural change in demand conditions. We consider short run (monthly) demand relationships for edible fats and oils. In that monthly quantities of fats and oils are likely to be relatively fixed, we utilize an inverse AIDS specification. Our analysis consists of two components. In the first, we utilize a smooth transition function to model a switching inverse almost ideal demand system (IAIDS) that assesses short-run demand conditions for edible fats and oils in the U.S. Our results suggest that short-run demand conditions for fats and oils experienced a rather rapid structural shift in the early 1990s. Although this shift generally made price flexibilities more elastic, differences in flexibilities across regimes are modest in most cases. Our results suggest that decreases in marginal valuations for most fats and oils in response to consumption increases are rather small. Scale flexibilities are relatively close to -1, suggesting near homothetic preferences for fats and oils. An important distinction occurs for lard and tallow, which exhibit a very elastic scale response. This suggests that scale increases in the consumption of edible fats and oils will significantly decrease consumers' marginal valuation of these animal fats. A second segment of our analysis considers dynamic extensions to the IAIDS model that recognize habit effects. Although nested hypothesis testing supports the dynamic specification over the static IAIDS model, price and scale flexibilities are quite similar to the static case.Demand and Price Analysis,
The [Ne III]/[Ne II] line ratio in NGC 253
We present results of the mapping of the nucleus of the starburst galaxy NGC 253 and its immediate surroundings using the Infrared Spectrograph on board the Spitzer Space Telescope. The map is centered on the nucleus of the galaxy and spans the inner 800 × 688 pc^2. We perform a brief investigation of the implications of these measurement on the properties of the star formation in this region using theories developed to explain the deficiency of massive stars in starbursts
Helping to Support CPC+ Initiative to Integrate Behavioral Health Within Primary Care: A Team-Based Approach to Improving Depression Management
AIM:
The objective of this project is to increase the rate of documented successful treatment of depression for both new and established diagnoses of depression at Jefferson Internal Medicine Associates (JIMA) from 29% to 50% over 12 months.https://jdc.jefferson.edu/patientsafetyposters/1027/thumbnail.jp
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