Investigating the Effects of Chronic Amphetamine Treatment on the Midbrain Superior Colliculus

Heightened distractibility, the reduced ability to filter out irrelevant information, is a disruptive symptom found in numerous conditions and healthy ageing. It is most effectively treated with psychostimulant drugs, such as amphetamine, which are given chronically in attention deficit hyperactivity disorder (ADHD). There is converging evidence linking the superior colliculus (SC) to the regulation of distractibility, and acute amphetamine administration is known to suppress collicular responsiveness, however relatively little is known about its mechanism of action and long lasting effects when administered chronically. It is therefore the aim of this thesis to investigate the effects of chronic treatment with amphetamine on the SC, as a neural correlate of distractibility. To achieve this, adolescent Hooded Lister rats were treated orally with amphetamine (2, 5 or 10 mg/kg) or a control (vehicle or untreated) for one month. The effects of treatment were then explored by investigating: collicular-dependant and locomotor behaviour; visual responsiveness of the superficial SC; responses to an acute amphetamine challenge; and the morphology of the superficial SC. At high doses, oral amphetamine treatment resulted in the development of locomotor tolerance, in contrast to previous research using i.p. administration which report sensitisation. Evidence of suppression of activity in the SC was identified from a reduced ability to perform collicular dependant behaviours, and from weaker light responsiveness measured from multi-unit activity in the superficial SC following treatment with high doses of amphetamine. Evidence was also found of a potential compensatory mechanism involving synaptophysin expression and enhanced peri-synaptic activity. This thesis also investigated the types of dendritic spines prevalent in the superficial SC for the first time, and found that these structures were unaffected by amphetamine treatment. These results indicate that the therapeutic effects of amphetamine may stem from suppression of collicular activity, and the SC is susceptible to amphetamine induced remodelling

Identification of dividing, determined sensory neuron precursors in the mammalian neural crest

Sensory and autonomic neurons of the vertebrate peripheral nervous system are derived from the neural crest. Here we use the expression of lineage-specific transcription factors as a means to identify neuronal subtypes that develop in rat neural crest cultures grown in a defined medium. Sensory neurons, identified by expression of the POU-domain transcription factor Brn-3.0, develop from dividing precursors that differentiate within 2 days following emigration from the neural tube. Most of these precursors generate sensory neurons even when challenged with BMP2, a factor that induces autonomic neurogenesis in many other cells in the explants. Moreover, BMP2 fails to prevent expression of the sensory-specific basic helix-loop-helix (bHLH) transcription factors neurogenin1, neurogenin2 and neuroD, although it induces expression of the autonomic-specific bHLH factor MASH1 and the paired homeodomain factor Phox2a in other cells. These data suggest that there are mitotically active precursors in the mammalian neural crest that can generate sensory neurons even in the presence of a strong autonomic-inducing cue. Further characterization of the neurons generated from such precursors indicates that, under these culture conditions, they exhibit a proprioceptive and/or mechanosensory, but not nociceptive, phenotype. Such precursors may therefore correspond to a lineally (Frank, E. and Sanes, J. (1991) Development 111, 895-908) and genetically (Ma, Q., Fode, C., Guillemot, F. and Anderson, D. J. (1999) Genes Dev. 13, in press) distinct subset of early-differentiating precursors of large-diameter sensory neurons identified in vivo

The Legal Case for Equity in Local Climate Action Planning

Over the last half decade, local climate action plans have regularly come to incorporate considerations of racial and socioeconomic equity, recognizing the ways in which low-income communities and communities of color experience earlier and worse consequences from global warming, and these communities are also at risk of being harmed by policies meant to address climate change. Until now, however, the discourse on equity in climate action planning has largely pertained to policy; it acknowledges the disproportionate harm that certain communities experience as a result of climate change and policies to address climate change, and suggests policy tools that can address these disparities. Missing is a discussion of why local governments are compelled or strongly encouraged by law to develop climate plans that aim to address racial and socioeconomic inequity alongside rising GHG emissions. This Article seeks to fill in the missing legal context for why equitable climate action planning is strongly encouraged by three aspects of federal law: the Equal Protection Clause of the Fourteenth Amendment of the U.S. Constitution, Title VI of the Civil Rights Act of 1964, and recent federal law developments like the Inflation Reduction Act and Justice40. While none of these mandate that local governments consider equity in their climate action planning, they do provide a compelling legal argument for local climate policy that is equitable and racially just. The Article explores all three areas of federal law and suggests ways in which they might interplay with equitable local climate action planning. In addition to delineating new applications for these areas of federal law, the research seeks to provide a legal rationale for local climate policy that is just and equitable that can support local government efforts when their climate action plans face political, fiscal, legal, and other forms of challenge

Cities, E-Commerce & Public Health: 3 Legal Pathways to Limiting Freight Vehicle Emissions

In recent years, cities have become increasingly defined by e-commerce – the sprawling network of goods delivery from central warehouses to neighborhood distribution centers to residents’ front doors. This growing network of warehouses and the freight vehicles that serve them contribute significantly to a community’s greenhouse gas emissions and exposure to harmful pollutants like nitrogen oxides (NOx), carbon monoxide and particulate matter. Moreover, so-called last-mile delivery warehouses (or distribution centers) are proliferating, largely in low-income communities and communities of color, where residents are exposed to increasing traffic, pollution, and harmful health impacts. While a handful of cities have pursued approaches to lessening tailpipe emissions from freight vehicles, such as through electric vehicle and cargo bike pilot programs, there is a clear gap in regulating the emissions attributable to e-commerce warehouses and the vehicles that enter and exit them. In part, cities have had difficulty limiting freight vehicle emissions because federal law preempts certain state and local vehicle restrictions. Three policy approaches are discussed herein: (1) rules for drayage trucks within California’s Advanced Clean Fleets rule; (2) site-based emissions standards for warehouses (also known as indirect source rules); and (3) zero-emissions delivery zones in which zero-emissions vehicles (ZEVs) have priority access to loading and unloading areas. Each of these presents legal complexity, but elements of them can be available to cities looking to control emissions associated with e-commerce delivery. Despite the relatively recent nature of e-commerce proliferation, last-mile delivery warehouses perpetuate longstanding patterns of environmental injustice, exposing low-income communities and communities of color to significant and harmful truck pollution. And though the federal law landscape can be murky, the CAA, EPCA and the FAAAA allow some room for local governments to place limits or otherwise address pollution and other e-commerce impacts. The legal tools available to address their impacts are necessarily evolving, and they offer significant promise, particularly for jurisdictions willing to calibrate an approach carefully to applicable legal frameworks and to their local context

Senior Recital:Amy Turner, Soprano

Kemp Recital Hall Friday Evening April 3, 1998 7:00 p.m

These people are not conquered like those of New Spain : Florida\u27s Reciprocal Colonial Compact

In 1605, Pedro de Ybarra, Governor of Florida, sent a terse note to Fray Benito de Blasco, a missionary who had gone behind his back to send his own envoy to the wild coast south of St. Augustine. These people are not conquered like those of New Spain, he warned him. This is a new land. 1 As the Spanish extended their influence over the New World, they encountered a broad range of environments and peoples, and how they related to them differed from place to place. The maritime periphery of Florida, which included parts of present-day South Carolina, Georgia, and Alabama, had non-agricultural Indians to the south, settled agriculturalists to the west, and seasonally mobile Indians to the north, center, and east. This article examines the chiefdom-presidio relationship that developed in Florida between 1565, when Spain first established a foothold on the east coast, and the early 1700s, when the presidio lost its hinterland. It addresses four fundamental questions: how the relationship came about, how it functioned, what the parties expected out ofit, and what conditions could sustain or undermine it. The Spanish have left us written sources. What the Indians thought must be gauged through their reported speech and their behavior

In A Little Town Near By

https://digitalcommons.library.umaine.edu/mmb-vp/4623/thumbnail.jp

Junior Recital:Amy Turner, Soprano Nancy Pounds, Piano

Kemp Recital Hall Saturday Afternoon November 22, 1997 1:30 p.m