Chronic exposure to psychostimulants such as amphetamine (AMPH) can induce long-term disruptions in cognition via actions on prefrontal cortex dopamine. Previous work has shown that two types of executive functions, set shifting and working memory (WM), are disrupted by AMPH sensitization and that these cognitive domains are impaired in schizophrenics and stimulant abusers. We assessed the effects of AMPH sensitization on behavioural flexibility using a cross-maze set shifting task and a WM task using the delayed spatial win-shift (SWSh) task in Long Evans (LE) and Sprague Dawley (SD) rats. Rats were exposed to an AMPH sensitization regimen (15 AMPH or saline injections: 1-5 mg/kg every 2nd day, increasing the dose by 1 mg every 3rd injections) following habituation on the mazes. In experiment 1, LE and SD rats were initially trained on a visual cue discrimination. During the set shift, rats were required to shift from the previously acquired visual-cue-based strategy to a response strategy (e.g.; always turn left, ignore the visual cue). For the reversal, rats were trained to reverse their turn direction. AMPH treatment did not impair learning of the initial cue discrimination in either strain. However, AMPH treated rats learned the response discrimination faster than controls during the set shift and AMPH treated LE rats were faster than controls to reach acquisition criterion during the response reversal. AMPH treatment neither impaired nor improved reversal learning in SD rats. In experiment 2, rats were tested on the SWSh task in which spatial information acquired during a training phase was used 30 minutes later during the testing phase in order to retrieve food pellets on the maze. In this task, AMPH treated rats were faster to re-attain criterion than control rats. Correlational analysis further revealed that AMPH sensitized rats that required more days to reach criterion before AMPH treatment (i.e. slow learners) tended to make more errors during re-acquisition of the memory task. Viewed collectively, these results suggest that chronic AMPH treatment can enhance behavioural flexibility and WM assessed in this manner. However, repeated AMPH exposure may have exacerbated pre-existing cognitive deficits in slow learning rats. / Medicine, Faculty of / Graduate

In this thesis, we shall attempt to present a study of certain properties of real functions related to the set property exhaustible.

No description available.

"The purpose of this paper is to examine the various statements of the Axiom of Choice and the Hausdorff Maximality Principle, and the Tychonoff Product Theorem; and to show that they are logically equivalent"--Preface. / "June, 1957." / Typescript. / "Submitted to the Graduate Council of Florida State University in partial fulfillment of the requirements for the degree of Master of Arts." / Advisor: James Watson Ellis, Professor Directing Paper. / Includes bibliographical references (leaf 46).

Indiana University-Purdue University Indianapolis (IUPUI) / Alcoholics often experience difficulties ceasing drinking, potentially related to excessive behavioral inflexibility that either precedes or results from high alcohol consumption. Components of the Wisconsin Card-Sorting Task (WCST) a type of Attentional Set-Shifting (AttSS) task measuring impairments in behavioral flexibility have been modified to measure similar constructs within animals. Previous work has shown impaired AttSS in abstinent alcoholics and nonalcoholic individuals with a family history of alcoholism, as well as in mice exposed to chronic-intermittent alcohol vapor (Gierski et al., 2013; Hu et al., 2015; Oscar-Berman et al., 2009). The aim of the current study was to assess whether selectively-bred High- vs. Low- Alcohol Preferring (HAP vs LAP) mice display behavioral inflexibility as measured by an operant AttSS task, and furthermore, whether a history of voluntary drinking in cross-bred HAP (cHAP) mice further increases inflexibility. Impairments in the AttSS task are assessed by evaluating the number of trials to reach criterion, as well as the number and types of errors committed during the second experimental phase. In Experiment 1, male and female HAP and LAP mice first learned to press one of two levers signaled by a visual cue, but random with respect to spatial orientation, for a 0.1% saccharin solution reward. The following experimental phase consisted of an egocentric discrimination, such that side (left or right) now signaled correct reinforcement and the location of the visual cue was irrelevant. In Experiment 2, prior to identical operant procedures as Experiment 1, male and female cHAP mice were given free-choice access to 10% alcohol or water for seven weeks. Ethanol-exposed animals drank an average of 29.6 g/kg/day.

Sweetpotato (Ipomoea batatas (L.) Lam.) is one of the major tropical root crops of the world and it is widely distributed throughout the tropical and temperate regions of Africa, Asia and the Americas. During harvest and post-harvest handling, the skin can be separated from the underlying tissue of the storage root. Storage root damage contributed to income losses for producers. To minimize these loses, producers set the skin of the sweetpotato by removal of the vines prior to harvest. New mechanical (undercutting) and cultural (biochar) methods were developed and tested. Mechanical undercutting would sever the feeder roots of the plant causing drought stress and initiate the skin set reaction. Application of biochar was used to change soil physical properties to reduce skinning in storage roots. The new practices may give producers options to increase the storage life of the crop.

No description available.

I den här studien diskuteras SET som metod i skolan. SET är en förkortning av social och emotionell träning. Studien baseras på intervjuer och observationer av två olika verksamheter och tre olika pedagoger samt två forskare försökt ta reda på hur metoden SET fungerar för pedagoger och elever. Frågeställningarna som användes är varför man ska införa SET i undervisningen och hur betydelsefullt SET är som arbetsmetod i skolan? Vad kan pedagoger göra idag för att minska psykisk ohälsa i skolan? Birgitta Kimber är grundaren av SET i Sverige, SET är ett evidensbaserat material sammanställt efter en studie hon genomfört i Oxford under en tidsperiod på fem år. En viktig slutsats är att SET fungerar som metod för social och emotionell träning men att andra metoder också fungerar. Metoderna är beroende av en skicklig och engagerad pedagog som har en förmåga att bilda en tydlig struktur. Barn behöver livskunskap, det är en fördel att skolan har det som ett undervisningsämne. Den grundläggande sociala och emotionella träningen bör emellertid ligga hos barnets vårdnadshavare, medan skolan är ett komplement.

No description available.

No description available.