Cholinergic innervation is necessary to shift reward timing activity in rodent visual cortex

While the biological analogue of prediction error has been well characterized in the midbrain dopaminergic system, the possibility of other neuromodulatory systems acting as global reinforcers is a topic of much debate. Reward timing, the phenomenon by which single unit responses in primary visual cortex (V1)
reflect an operantly learned stimulus‐reward interval, offers a tractable preparation to investigate reinforcement learning in vivo: theoretical work suggests that reward timing results from the interaction of stimulus‐evoked recurrent network activity and a global reinforcement signal that indicates the time of
received reward. We hypothesized that this signal is conveyed by cholinergic neurons arising from the basal forebrain (BF), a strong candidate system that projects globally to most cortical regions, has a known role in plasticity, and is involved in attention and the representation of salience. To test the necessity of such a signal in entraining reward timing in V1, rats were trained on an initial stimulus‐reward contingency, received a neurotoxin in V1 that eliminated BF cholinergic terminals, and subsequently trained on a second contingency. We found that extracellular single unit recordings from V1 of lesioned animals, but not saline‐infused controls, failed to show shifted neural reports of reward that matched the new contingency. Importantly, neurons of
lesioned animals continued to display intervals associated with the initial contingency, arguing that cholinergic input is required to learn, but not to express, reward timing activity

Economic Optimization of Innovation and Risk

No abstract availabl

The Effects of Microgravity on Liver Function in Mouse

The environment of space is one that is currently of great interest to researchers. With so little known concerning microgravity and radiation, both areas pose a particular interest in regards to living organisms. Microgravity is a term commonly applied to a condition of free-fall within a gravitational field in which the weight of an object is reduced compared to its weight at rest on Earth. Upon exposure, the body undergoes numerous changes, especially at the cellular level. Evidence has shown conclusively that many of these effects increase in severity when space travel is extended to long term. Several studies carried out using both invitro and invivo model systems suggest that microgravity induces oxidative stress. Oxidative stress may result in the disturbance and equilibrium status of pro-oxidant/anti-oxidant systems which will cause extensive damage to all the organ systems. Some of the oxidoreductase class of enzymes present in the liver scavenges the reactive oxygen species induced during micro gravity. These enzymes are of particular importance, because they help to protect organisms from oxidative and free radical damage. Hence the objective of the present study is to understand the effect of microgravity on the specific activity of various oxidoreductases and some other stress induced parameters in the mouse liver. Very little is known about 1 2 the effect of microgravity on oxidoreductase class of enzymes. We use in our studies the most popular ground based rodent model known as the hind limb unloading. In this model the mice are suspended by the tail base to produce 30-degree head down position, which simulates microgravity conditions. This study will help to understand the liver functions during microgravity conditions

A Balancing Act: A Discussion of Gender Roles Within Wiccan Ritual

This presentation argues that the liminal space of Wiccan ritual modifies practitioners’ gender roles by inscribing both masculine and feminine roles upon the individual to create balance. Under Victor Turner’s theory of liminality ritual becomes a function of society that helps fulfill a social need to be outside normal social processes, including gender roles. Ritual is a way of stepping outside of normal time and space to create and live the ideal, if only for a moment, that is nearly impossible to realize in everyday life. Every aspect of Wiccan ritual is aimed towards enacting and embodying balance and unity, even the altar and the circle itself. As the priest and priestess enact the divine coupling in order to instruct and guide the other participants, the solitary practitioner enacts this coupling of masculine and feminine within himself to create a gender role that is outside of the normal understanding of gender, one that is divine. The modified gender role that comes out of the liminal space as it meets with the concept of balance is a representation of unity, of wholeness, which is so pervasive in Wicca

Social and economic effects of urban renewal in Kansas City, MO : Census tracts 24 and 33

In an effort to revitalize urban cores, and to maintain competition with rapidly rising suburbs, the federal government equipped cities with new tools in the mid-20th century. But the federal government’s redevelopment plans focused primarily on highway development and land clearance and this focus has led to a breakdown of urban districts with vibrant, active neighborhoods and gave rise to concentrated and cyclical poverty, and a concomitant rise in business flight from urban centers. This paper focuses on the outcome of urban renewal projects in Kansas City’s census tracts 24 and 33

Letter, Chester E. Shuler to Henry E. Luhrs, March 11, 1934

This typed letter, dated March 11, 1934, is written from Chester E. Shuler to Henry E. Luhrs as a response to Luhrs letter of March 5, where-in he had requested information on Zachary Shuler\u27s experience hearing President Lincoln\u27s Gettysburg address in person. Shuler responds that his father has passed but offers to send Luhrs a carbon copy of the newspaper article Shuler had published about his father\u27s recollections on the subject. A handwritten post script about an enclosed likeness of Zachary Shuler is below the Shuler\u27s signature on the second page of the letter.https://scholarsjunction.msstate.edu/fvw-manuscripts-original-manuscripts/1188/thumbnail.jp

Implications of Swelling Clays on Asphalt Pavement Performance in Colorado

Asphalt pavements constructed directly over high plasticity clays appear to be more susceptible to premature cracking parallel to the gutter on curb and gutter pavement cross sections than pavements with crushed stone bases. This paper describes five factors common to two sites studied that may be contributors to this early distress. These factors are: cracking is top-down; moisture content of the subgrade soils beneath the cracks is higher than optimum; density of the subgrade soils beneath the cracks is lower than optimum; subgrade soils are highly plastic; full-depth construction; and all pavements had curb and gutter typical sections. In addition, similar pavements constructed on crushed stone bases in the vicinity of the full-depth pavements with the same construction and materials characteristics do not display this cracking. Results of this work warrant study of construction techniques with regard to optimum moisture and density requirements when paving full-depth asphalt over plastic clays

THE IMPACT OF THE TOTAL LEADERSHIP MODEL ON FINANCIAL PERFORMANCE FOR HEALTH CENTER ADMINISTRATORS

The purpose of this study is to examine the extent to which a leadership model impacts the financial performance of one organization. The organization has multiple centers, each with its own leader. A survey is used to gauge the value alignment of the selected leadership model on each center leader within this organization. The model used for this study is the Total Leadership model which has the main goal of improving performance in four domains of life: work, home, community and self by creating mutual value within each therefore creating value alignment