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PubMed2005

Transposition in pigeons: reassessing Spence (1937) with multiple discrimination training.

We studied transposition in pigeons, using multiple-pair discrimination training. Four birds discriminated two pairs of circles: 1+ 2- and 5+ 6- or 1 - 2 + and 5- 6 + (digits denote circle diameters and plus and minus signs denote reward and nonreward, respectively). Four other birds discriminated four pairs of circles: 1+ 2-, 1+ 3-, 4+ 6-, and 5+ 6- or 1- 2 +, 1- 3 +, 4- 6+, and 5- 6+. Finally, 4 birds discriminated only one pair of circles: 1+ 2-, 1- 2+, 5+ 6-, or 5- 6+. Testing included five new pairs--1/5, 2/3,2/6,3/4, and 4/5--that distinguished absolute from relational accounts of transposition. The pigeons' relational responding rose from one- to two- to four-pair training. The similarity of the testing stimuli to one another also affected relational responding: Transposition increased with highly dissimilar stimuli. Neither Spence's (1937) theory nor existing relational accounts could predict the obtained pattern of relational responding.

Animals↗
PubMed1999

The role of the medical examiner in mass casualty situations with special reference to the Alfred P. Murrah Building bombing.

OBJECTIVE: To describe the events that shaped the investigation by the Oklahoma Office of the Chief Medical Examiner with regard to the terrorist bombing of the Alfred P. Murrah Federal Building in Oklahoma City in 1995 and to provide lessons learned for reinforcement and future planning. STUDY POPULATION: All persons known to have been killed by the blast. METHODS: Standard forensic techniques with regard to crime scene investigation, documentation, body identification and cause of death determinations were followed. MAIN OUTCOME MEASURES: Fatality injury and related evidence documentation. RESULTS: A total of 168 people died principally from secondary and tertiary injuries caused by projectiles, victim displacement, and crushing. Emphasis is placed on the methods of operation required to find, remove, identify, and determine cause of death in these individuals. Simultaneously, evidence must be identified and preserved in a homicide investigation of this type. Close cooperation must exist among multiple varied agencies and disciplines to accomplish the task and to prepare for subsequent analysis and courtroom testimony required by the criminal justice system. CONCLUSIONS: Terrorism, both foreign and domestic, is a current fact and will be a problem in many forms in the 21st century. No one is immune. The key to success is to plan ahead and be aware of available resources. Preplanning for short comings and difficult issues, and most importantly, relying on team work will allow future participants to successfully meet and complete the challenge. The investigation developed detailed injury data and mechanisms that were available for subsequent judicial proceedings and for in-depth epidemiological studies spearheaded by the Injury Prevention Service of the Oklahoma State Department of Health.

Coroners and Medical Examiners↗
PubMed1975

Long-term effectiveness of imagery instructions with retarded persons.

The effects of imagery instructions on paired-associate learning efficiency and on the retention of 16 picture pairs were investigated using two groups of EMR individuals with approximate mental ages of 8 and 11 years, respectively. While facilitated list mastery was obtained under imagery instructions, no facilitation was found for 1-week retention performance. However, in learning a new list immediately following the retention task, those individuals who had received imagery instructions during original learning continued to exhibit facilitated learning. These results extend previous work.

Adolescent↗
PubMed2002

Identification of the nicotinic receptor subtypes expressed on dopaminergic terminals in the rat striatum.

Neuronal nicotinic acetylcholine receptors (nAChRs) expressed on mesostriatal dopaminergic neurons are thought to mediate several behavioral effects of nicotine, including locomotion, habit learning, and reinforcement. Using immunoprecipitation and ligand-binding techniques, we have shown that both alpha6beta2* and alpha4(nonalpha6)beta2* nAChRs are expressed in the caudate-putamen and that only alpha6* nAChRs can bind alpha-conotoxin MII and methyllycaconitine with affinities of 1.3 and 40 nm, respectively. Further studies performed on 6-hydroxydopamine-lesioned striatum led to the identification of nAChR subtypes selectively expressed on dopaminergic terminals [alpha4alpha5beta2, alpha4alpha6beta2(beta3), and alpha6beta2(beta3)], nondopaminergic neuronal structures (alpha2alpha4beta2), or both structures (alpha4beta2). The identification of the nAChRs expressed on striatal dopaminergic terminals opens up the possibility of developing selective nAChR ligands active on dopaminergic systems and associated diseases, such as Parkinson's disease.

Animals↗
PubMed2002

Timing in pigeons: effects of the similarity between intertrial interval and gap in a timing signal.

Previous research suggests that when a fixed interval is interrupted (known as the gap procedure), pigeons tend to reset memory and start timing from 0 after the gap. However, because the ambient conditions of the gap typically have been the same as during the intertrial interval (ITI), ambiguity may have resulted. In the present experiment, the authors found that when ambient conditions during the gap were similar to the ITI, pigeons tended to reset memory, but when ambient conditions during the gap were different from the ITI, pigeons tended to stop timing, retain the duration of the stimulus in memory, and add to that time when the stimulus reappeared. Thus, when the gap was unambiguous, pigeons timed accurately.

Animals↗
PubMed1976

[Anxiety of hysterical exaction (author's transl)].

Fear in childhood is a quite common symptom and varies in importance according to age and stage of development. Intelligence, psychic constitution and special sensibility influence and coin the readiness and reasons for fear. Fear, however, can also be learned by reinforcement, imitation and identification. The reaction of the environment, in particular that of the parents, may fix physiological fear reactions of the child and these may be used in order to derive advantage. By means of several cases the reader is shown that fear in childhood is not rarely the expression of hysterical exaction. This publication wants especially to point to this kind of child neurosis because of the fact that even physicians and pedagogues submit to this exaction of pity and instead of demanding adequate work treat the child with indulgence or advise to do so. In this way the wrong attitude of the child becomes even more fixed. By his reception at a psychiatric ward for children this circulus vitiosus is usally soon interrupted. If the success of this therapy is to last, the treatment and advise of the whole family must begin synchronously and must often be continued for a long time.

Anxiety↗
PubMedDate not supplied

Infant oral health education for pediatric and family practice residents.

PURPOSE: The purpose of this study was to investigate whether an infant oral health curriculum implemented in pediatric and family medicine residency programs could improve physicians' oral health knowledge and practice behaviors and promote the age 1 dental visit. METHODS: Residents and faculty members completed a baseline current practices survey and knowledge test before receiving a 1- or 2-hour training session followed by a knowledge post-test. Existing well child care forms were updated with oral health prompts to reinforce newly learned skills. At 1-year follow-up (1 YFU), participants completed a current practices survey and knowledge test. In addition to the residency programs, medical students and advanced practice registered nurses participated in baseline data collection, training, and immediate posttest data collection. RESULTS: A total of 245 people participated, with 78% trained in person and 22% trained via the Web. Of these, 120 were the targeted residents and faculty-of whom 82% completed the 1 YFU. Practice behaviors improved from baseline to 1 YFU, with only 28% of practitioners at baseline referring children to the dentist at age 1, compared to 73% at 1 YFU (P<.05). Knowledge scores were greater at 1 YFU than at baseline (P<.05), and the mode of training showed no difference in knowledge outcomes. Knowledge and prescribing practices regarding fluoride were poor at baseline and showed limited improvement at 1 YFU. CONCLUSIONS: An infant oral health education program can improve physicians' oral health knowledge and behaviors, particularly regarding promoting the age 1 dental visit. Behavior changes regarding fluoride prescribing, however, appear harder to achieve. Web-based training had similar success to in-person training.

Chi-Square Distribution↗
PubMed1989

[Medical graduate and basic education in Austria: emergency or surplus? Objective evaluation or bureaucratic regimentation?].

If there is a reform of medical school, it will be desirable to keep the positive aspects of our tradition, while adding favourable aspects out of international experience. We will need to shorten unprofitable ballast, which means theory in excess, seeking for more practical and well accessable knowledge capability of independent work and decisionmaking. We need better communication ("humanization") in medicine. It is necessary to take the whole education system into consideration: college up to professorship, as they are linked together. We cannot recommend to increase the number of exams, but we support a continuating control, working in small groups promoting the motivation of the students. They must see more sense in their studies. Rather intensify the control and supervision of the system of instruction than to reinforce the learning control of students by exams. We reject to explain all failures and disappointments in medical school by lack of financial means or because of competences which overlap each other. Many things could be changed within existing laws. Partly they have to be changed by altering laws. A number of practical possible ways to reach this target are pointed out here.

Austria↗