Adaptive Parallel Iterative Deepening Search

Many of the artificial intelligence techniques developed to date rely on heuristic search through large spaces. Unfortunately, the size of these spaces and the corresponding computational effort reduce the applicability of otherwise novel and effective algorithms. A number of parallel and distributed approaches to search have considerably improved the performance of the search process. Our goal is to develop an architecture that automatically selects parallel search strategies for optimal performance on a variety of search problems. In this paper we describe one such architecture realized in the Eureka system, which combines the benefits of many different approaches to parallel heuristic search. Through empirical and theoretical analyses we observe that features of the problem space directly affect the choice of optimal parallel search strategy. We then employ machine learning techniques to select the optimal parallel search strategy for a given problem space. When a new search task is input to the system, Eureka uses features describing the search space and the chosen architecture to automatically select the appropriate search strategy. Eureka has been tested on a MIMD parallel processor, a distributed network of workstations, and a single workstation using multithreading. Results generated from fifteen puzzle problems, robot arm motion problems, artificial search spaces, and planning problems indicate that Eureka outperforms any of the tested strategies used exclusively for all problem instances and is able to greatly reduce the search time for these applications

Reduced GABA-B/GIRK-mediated regulation of the VTA following a single exposure to cocaine

In this paper, Arora and colleagues expand on their previous work on GIRK channels in the ventral tegmental area (VTA) presenting evidence that a single exposure to cocaine reduces inhibitory GABAergic transmission to dopamine (DA) neurons in the ventral tegmental area. Mice receiving i.p. injections of cocaine saw a short lived (1-5 days) decrease in GABAb mediated G-protein coupled inwardly-rectifying potassium (GIRK) currents in DA neurons in the VTA. This decrease parallels an NMDA-mediated increase in the frequency of glutamatergic neurotransmission. Chronic cocaine injections had no additional effects beyond those seen with single injections. Though they found no change in mRNA levels for GABAb receptors, GIRK channels, or RGS-2 (a G-protein regulator), immunoelectron microscopy indicated a decrease in levels of GIRK channels in the plasma membrane of the dendrites of VTA DA neurons. The cocaine-mediated decrease in GIRK currents was abolished in the presence of D2/3R antagonist sulpiride, but not in the presence of D1/5 antagonist SCH23390, indicating a link between D2/3 receptor activation and GIRK activity. Interestingly, the addition of quinpirole, a D2/3 agonist, elicited similar GIRK currents, though they were smaller than those mediated by GABAb receptors. Similarly, acute injections of cocaine significantly diminished quinpirole-evoked currents

Visual Arts Activities Relate to Cortisol and Observed Interest for Preschool Children

This study examined the impact of various visual arts activities on physiological stress response and observed emotion regulation. The first aim of the study was to confirm and expand on results from past investigations showing that visual arts classes relate to lower levels of the stress hormone cortisol and greater observed interest for young children facing economic hardship. This investigation expanded on these findings by examining the effects of individual visual arts activities on cortisol and observed interest in comparison to other preschool activities. Participants were 72 children, ages 3-5 years, who attended a Head Start preschool and were randomly assigned to participate in different schedules of arts and homeroom classes. Children were videorecorded in preschool classes and a well validated observational system was applied to measure observed emotion. Children provided salivary samples at multiple times of day and immunoassays tested levels of the stress hormone cortisol. Results of hierarchical linear modeling indicated that children showed greater interest and lower cortisol in visual arts classes compared to all other classes. Results also showed that child participation in painting and drawing tables was associated with greater interest, as was participation at the teacher art table, with no significant effect for the clay table. Of the four visual arts activities examined in this study, only the teacher art table was associated with lower levels of cortisol. Teacher involvement may be a key factor in the effects of visual art on both stress and interest

mGluR5 knockout mice exhibit normal conditioned place-preference to cocaine

Metabotropic glutamate receptor 5 (mGluR5) null mutant (-/-) mice have been reported to totally lack the reinforcing or locomotor stimulating effects of cocaine. We tested mGluR5 -/- and +/+ mice for their locomotor and conditioned place- preference response to cocaine. Unlike the previous finding, here we show that compared to mGluR5 +/+ mice, -/- mice exhibit no difference in the locomotor response to low to moderate doses of cocaine (10 or 20 mg/kg). A high dose of cocaine (40 mg/kg) resulted in a blunted rather than absent locomotor response. We tested mGluR5 -/- and +/+ mice for conditioned place-preference to cocaine and found no group differences at a conditioning dose of 10 mg/kg, suggesting normal conditioned rewarding properties of cocaine. These results differ substantially from Chiamulera et al. (2001) and replicates Olsen et al., (2010), who found normal cocaine place-preference in mGluR5 -/- mice at 5 mg/kg. Our results indicate mGluR5 receptors exert a modulatory rather than necessary role in cocaine-induced locomotor stimulation and exert no effect on the conditioned rewarding effects of cocaine

Gulf War Syndrome: A role for organophosphate induced plasticity of locus coeruleus neurons

Gulf War syndrome is a chronic multi-symptom illness that has affected about a quarter of the deployed veterans of the 1991 Gulf War. Exposure to prolonged low-level organophosphate insecticides and other toxic chemicals is now thought to be responsible. Chlorpyrifos was one commonly used insecticide. The metabolite of chlorpyrifos, chlorpyrifos oxon, is a potent irreversible inhibitor of acetylcholinesterase, much like the nerve agent Sarin. To date, the target brain region(s) most susceptible to the neuroactive effects of chlorpyrifos oxon have yet to be identified. To address this we tested ability of chlorpyrifos oxon to influence neuronal excitability and induce lasting changes in the locus coeruleus, a brain region implicated in anxiety, substance use, attention and emotional response to stress. Here we used an ex vivo rodent model to identify a dramatic effect of chlorpyrifos oxon on locus coeruleus noradrenergic neuronal activity. Prolonged exposure to chlorpyrifos oxon caused acute inhibition and a lasting rebound excitatory state expressed after days of exposure and subsequent withdrawal. Our findings indicate that the locus coeruleus is a brain region vulnerable to chlorpyrifos oxon-induced neuroplastic changes possibly leading to the neurological symptoms affecting veterans of the Gulf War

The Development of a Device for the Evaluation of the Textiles and Clothing Core Course

(Introduction) Evaluation, as an integral part of the teaching-learning process, is of prime importance to those involved with educational programs. Institutions of higher learning are faced with the difficult task of presenting an integration of knowledge among numerous fields of interest. Evaluating progress, or the lack of progress, of student comprehension of this integration of knowledge is an essential aspect of this task. Evaluation of a course involves the clarification of objectives, the development and use of a variety of ways of assessing changes in students, meaningful ways of summarizing and interpreting that evidence, and use of the information gained to improve the curriculum, teaching, and guidance of the educational process.1 In 1962, the College of Home Economics staff members undertook the responsibility of revising the undergraduate curricula. This study resulted in the development of new curricular requirements in 1964. One of the major outcomes was the identification of the core curriculum as a means of unifying the home economics instructional program. The structure of the core curriculum provides the opportunity for developing a conceptual framework expressing the coherence in the major subject matter areas—Child Development and Family Relations; Food Service and Institution Management; Home Management, Equipment, and family Economics; Nutrition; Related Art, Crafts, and Interior Design; Textiles and Clothing. In addition to the departmental core courses, an introductory course, involving guidance for the selection of a specialization area, is required of first quarter freshmen. A Senior Seminar, with subject matter emphasis placed on the role of women, particularly home economists, in today’s world, is the concluding core course required of all home economics undergraduate students. The encompassing goal of this curricular structure is the identification of the interrelationships of objectives among the specialization areas. Students are presented with the opportunity of organizing information, identifying values, improving skills, and transferring knowledge into concepts to serve as bases for enlightening the educational experiences of each student. Evaluation of the degree to which this encompassing goal and other educational goals have been achieved is a basic part of instruction. Curriculum development must be concerned with evaluation. No other function of the teaching situation will govern the way curriculum experiences are planned and carried out so much as the manner in which evaluation of outcomes is performed.2 The success of the pupil in reaching the goal, hence the success of the educational program, is evaluated in terms of the objectives.3 Staff members of the Textiles and Clothing Department recognized the need for an evaluation of their core course, “The Cultural and Functional Aspects of Textiles and Clothing” (hereafter referred to as the Textiles and Clothing Core Course). This course, offered first in the Spring Quarter, 1966, has been offered during three quarters of the 1966-1967 academic year. Thus far, an evaluative device specifically designed for ascertaining the effectiveness of the core course had not been developed. Therefore, evaluation of the degree of attainment of the goals and objectives of interrelated, conceptual knowledge seemed desirable and appropriate. The author of this study has assisted with the operation of the class and was therefore in a position to develop and carry through an evaluative study of the course. The study involved a clarification of objectives of the core course, the development and administration of an evaluative device, and an analysis and summarization of the resulting data. Evaluation is an on-going, never-ending process; therefore, this particular study shall hopefully serve as the instigator of meaningful, continuing evaluation of the Textiles and Clothing Core Course

A Pedestal of Power: Analyzing Consciousness in Nonhuman Animals

Humans have an understanding of a concept called consciousness. This idea of consciousness has been the main separating factor between animals and humans regarding humankind\u27s purported superiority of intelligence: humans are conscious and other animals are not. Specifically, it is self-consciousness, awareness of oneself as oneself, that is. Yet extensive research throughout the last few decades shows that this may not be the case. Animals and humans alike show a variety of forms of consciousness and self-consciousness based on the structure of their bodies, brains, habitats and other contributing factors of survival. Hence, I will argue that humans are not the only beings on this Earth that have the ability of sophisticated consciousness and even self-awareness that we take as the result of a seemingly higher power of intelligence. To do so, I will examine a variety of cases where animals show various levels of consciousness. These animals include the four types of great apes, dolphins, horses, corvids, cephalopod mollusks, cows, lions, and canines. Such examples of higher consciousness derived from these animals include a being\u27s understanding of self, creating non-heritage based friendships, tool-making abilities, functional memory usage, and spatial awareness. Humans must now act upon this inheritance of knowledge regarding animal consciousness. If we know that other animals behold higher levels of intelligence, we must learn to treat them justly

Control over stress induces plasticity of individual prefrontal cortical neurons: A conductance-based neural simulation

Behavioral control over stressful stimuli induces resilience to future conditions when control is lacking. The medial prefrontal cortex(mPFC) is a critically important brain region required for plasticity of stress resilience. We found that control over stress induces plasticity of the intrinsic voltage-gated conductances of pyramidal neurons in the PFC. To gain insight into the underlying biophysical mechanisms of this plasticity we used the conductance- based neural simulation software tool, NEURON, to model the increase in membrane excitability associated with resilience to stress. A ball and stick multicompartment conductance-based model was used to realistically fit passive and active data traces from prototypical pyramidal neurons in neurons in rats with control over tail shock stress and those lacking control. The results indicate that the plasticity of membrane excitability associated with control over stress can be attributed to an increase in Na+ and Ca2+ T-type conductances and an increase in the leak conductance. Using simulated dendritic synaptic inputs we observed an increase in excitatory postsynaptic summation and amplification resulting in elevated action potential output. This realistic simulation suggests that control over stress enhances the output of the PFC and offers specific testable hypotheses to guide future electrophysiological mechanistic studies in animal models of resilience and vulnerability to stress

Nicotinic α7 acetylcholine receptor-mediated currents are not modulated by the tryptophan metabolite kynurenic acid in adult hippocampal interneurons

The  tryptophan  metabolite,  kynurenic  acid (KYNA),  is  classically  known  to  be  an antagonist  of ionotropic glutamate receptors. Within the last decade several reports have been published suggesting that KYNA also blocks nicotinic acetylcholine receptors (nAChRs) containing the α7 subunit (α7*). Most of these reports involve either indirect measurements of KYNA effects on α7 nAChR function, or are reports of KYNA effects in complicated in vivo systems.  However, a recent report investigating KYNA interactions with α7 nAChRs failed to detect an interaction using direct measurements of α7 nAChRs function.  Further, it showed that a KYNA blockade of α7 nAChR stimulated GABA release (an indirect measure of α7 nAChR function) was not due to KYNA blockade of the α7 nAChRs. The current study measured the direct effects of KYNA on α7-containing nAChRs expressed on interneurons in the hilar and CA1 stratum radiatum regions of the mouse hippocampus and on interneurons in the CA1 region of the rat hippocampus.  Here we show that KYNA does not block α7* nACHRs using direct patch-­clamp recording of α7 currents in adult brain slices