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Whether reward omission on the sample runs of a delayed alternation task would reduce proactive interference was tested in two experiments. On the first run of a trial, the animal entered one arm of a maze to obtain a food reward; on the second run the reward was available in the opposite arm. Alternation declined across a block of massed trials, but there was less of a decrease when the reward was omitted in the final trial or when another maze was substituted. In a task that required retention of three mazes at a time, alternation again declined across massed trials but was reinstated either by omitting the reward on the final trial or by substituting a different reinforcer. The results suggest that altering the reward outcome can improve memory discriminability of recently visited maze locations and thereby overcome trace confusion in memory., Proactive interference (PI) refers to a decline in recall across a series of trials that involve the same or similar to-be-remembered stimuli. Release from PI occurs when the target stimulus, [...]

A study analyzing the moral reasoning and behavior behind the stealing of clothes by juveniles is presented. The methods for controlling such juvenile delinquencies by planning behavior during development age are also discussed.

High school students of southwest states are studied for global self-esteem for teens. The various factors such as gender, delinquent status and social acceptance were considered for the study.

The phase correlation method (PCM) is known to provide straightforward estimation of rigid translational motion between two images. It is often claimed that the original method is best suited to identify integer pixel displacements, which has prompted the development of numerous subpixel displacement identification methods. However, the fact that the phase correlation matrix is rank one for a noise-free rigid translation model is often overlooked. This property leads to the low complexity subspace identification technique presented here. The combination of non-integer pixel displacement identification without interpolation, robustness to noise, and limited computational complexity make this approach a very attractive extension of the PCM. In addition, this approach is shown to be complementary with other subpixel phase correlation based techniques. Index Terms--Phase correlation method, subpixel image registration, SVD.

An approach is proposed for estimating dynamic magnetic resonance imaging (MRI) sequences. The approach is based on two complimentary strategies: an adaptive framework for estimating the MRI images themselves; and an adaptive technique for tailoring MRI system excitations for each data acquisition.

Research has been conducted on complex polyketide toxin cercosporin degradation. The screening analysis and characterization of the degrading phenotype and the study of the nontoxic cercosporin breakdown product are discussed.

A variety of opine-catabolizing pathogenic Agrobacterium and Pseudomonas bacteria are present in the crown galls of plants such as grape, plum and blackberry. An analysis of 43 crown galls shows that the most abundant opine is nopaline while octopine is absent. The tumors of wild blackberry contain an unidentified iminodiacid of the succinamopine-leucinopine type. Plum and cherry tumors show a good relation between the presence of opine and opine-using bacteria. However, apple and plum tumors contain the bacteria but no opine. Some tumors also contain opine-using nonpathogenic bacteria.

Reward omission was used to produce retroactive interference in a serial delayed-alternation task. Rats were given forced choices in 3 T mazes presented in succession followed by free choices in which the alternate arm in each maze was rewarded. Nonreward during the delay between forced- and free-choice runs produced a decrement in performance (i.e., retroactive interference) in comparison to reward during the delay. Interference in retention of the first maze in a list occurred when the second maze contained surprising reward or omission (i.e., an outcome contrary to previous training in that maze) in comparison to expected reward or omission. In addition to producing retroactive interference, omission sometimes increased alternation in the maze in which it occurred. These results support a differential rehearsal hypothesis of spatial memory.

Names are more difficult to recall than other facts about people such as occupations even when the words are nominally the same, e.g., Baker and baker. Subjects studied face photographs labeled with a surname and a medical diagnosis. Eponymous disorders were selected so that a given name could be used either as surname or diagnosis, e.g., Ms. Hodgkins or Hodgkin's disease. Nursing students (n=24) tested in a within-subjects design recalled more eponymous diseases than surnames. There were few instances of confusing names and diseases, but names were often recalled to the wrong face. Education students (n = 18) recalled fewer diseases than did the nurses, and there was no difference in their recall of names and diseases. Nursing students tested in a between-groups design (n=22 each) showed no impairment in name recall. The results suggest limitations in the role of meaningfulness in recall.

Names are typically more difficult to learn and remember than are other personal facts, such as occupations. The recall of names and occupations was compared when the items were nominally matched by using homonyms, that is, words that could be either surnames or occupations (e.g., Mr. Cook, or cook). This manipulation was made in between-groups as well as within-subjects designs. College student subjects studied face photographs labeled with a surname or an occupation. The designation of a common set of homonyms as names or occupations varied between two groups of subjects. For a third group, the homonyms were used as names and occupations for different pictures in a within-subjects comparison. In the between-groups comparison, names were not recalled significantly less well than occupations, whereas in the within-subjects comparison, names were recalled less well than occupations. Name recall in the within-subjects group was significantly less than recall in the name-only group. The difficulty in name recall may be due to characteristics of the verbal items used, such as meaningfulness, and the use of either between- or within-subjects designs., Psychologists have often noted the difficulty we seem to have in recalling people's names, especially in relation to recall of other kinds of personal information. For example, G. Cohen and [...]

Research shows that prolonged incubation with mannopine as the sole carbon source results in spontaneous mutations in nopaline-type strains C58 and T37 as well as the cured strain A136 of Agrobactrium tumefaciens. The mutants were able to catabolize mannopine, mannopinic acid and mannityl opine analogs. Hybridization studies with probes representing regions of mannopine catabolism showed that the spontaneous mutations were different from genes of opine catabolism or the Ti-plasmid- encoded genes.

Research shows that Agrobacterium tumefaciens 15955 can utilize either succinate or mannopine as its carbon source. Incubation in a mixture of these two compounds resulted in a diauxic growth pattern wherein succinate is consumed in the initial growth phase. Aftera distinctive lag dependent on the mode of preparation of inoculum, growth is continued using mannopine. Fumarate and malate likewise induced diauxic growth on strain 15955 when incubated with mannopine. However, incubation with succinate plus mannose and glutamine, the two possible catabolic intermediates of mannopine, does not result in diauxie.

INTRODUCTION Federal statutes imposing liability for hazardous waste cleanup costs raise numerous issues directly affecting the personal liability of directors and officers ("D&Os"). The most important issues of concern to [...]

A study analyzing implications of delinquent risk behavior or shoplifting involvement is presented. Self-perception of morality has been examined using predictors like adolescent self-concepts and self-worth.

A principal-component factor analysis was conducted which revealed two factors of parent-child relationships, global self-worth and morality. Multiple regression analysis revealed strong positive effects of parents on self-respect and interaction. Healthy parent-child relationship helps delinquent adolescent to develop positive self esteem and self worth.

History tells us that use of the crushed dried flowers of the daisy Chrysanthemum coccineum as an insecticide was a long-established folk practice in the Caucasus region and Northwest Persia. [...]

As a status report on a new, rapidly developing field, this book, a monograph in the series Recent Advances in Phytochemistry written by pioneers in the field of genetic engineering [...]

Research into the problem of reduced-order magnetic resonance imaging (MRI) acquisition is presented. It was possible to develop a problem formulation, linked analysis, and a computational technique to identify a set of excitation and reconstruction vectors for efficient MRI acquisition of an arbitrarily shaped region of interest.