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PubMed2005

Metrical categories in infancy and adulthood.

Intrinsic perceptual biases for simple duration ratios are thought to constrain the organization of rhythmic patterns in music. We tested that hypothesis by exposing listeners to folk melodies differing in metrical structure (simple or complex duration ratios), then testing them on alterations that preserved or violated the original metrical structure. Simple meters predominate in North American music, but complex meters are common in many other musical cultures. In Experiment 1, North American adults rated structure-violating alterations as less similar to the original version than structure-preserving alterations for simple-meter patterns but not for complex-meter patterns. In Experiment 2, adults of Bulgarian or Macedonian origin provided differential ratings to structure-violating and structure-preserving alterations in complex- as well as simple-meter contexts. In Experiment 3, 6-month-old infants responded differentially to structure-violating and structure-preserving alterations in both metrical contexts. These findings imply that the metrical biases of North American adults reflect enculturation processes rather than processing predispositions for simple meters.

Adolescent↗
PubMed2004

Chimpanzees remember the results of one-by-one addition of food items to sets over extended time periods.

Four chimpanzees were highly accurate in selecting the larger of two concurrent accumulations of bananas in two opaque containers over a span of 20 min. One at a time, bananas were placed into the containers, which were outside the chimpanzees' cages. The chimpanzees never saw more than one banana at a time, and there were no cues indicating the locations of the bananas after they were placed into the containers. The performance of these animals matched that of human infants and young children in similar tests. The chimpanzees were successful even when the sets to be compared were sufficiently large (5 vs. 8, 5 vs. 10, and 6 vs. 10) to cast doubt on the possibility that the chimpanzees were using an object file mechanism. These chimpanzees are the first nonhuman animals to demonstrate extended memory for accumulated quantity.

Animals↗
PubMedDate not supplied

Social acceptance of the physically handicapped child in the ordinary school.

It has been recommended by both the Snowdon and Warnock reports that greater efforts should be made to provide integrated education for physically handicapped children. The attitudes of the peer group toward the child with a physical handicap are of particular importance in deciding whether to integrate or segregate the disabled child. The present paper reports an exploratory study carried out in schools in Scotland, the purpose of which was to examine the social acceptability of the physically handicapped child in the ordinary school. The subjects, 38 children in the age group 9--11 years, of normal intelligence and with visible physical handicaps affecting movement, were drawn from ordinary day schools. A normal sample of control children was also studied. A modified version of Centers & Centers Social Discrimination test (1963) was administered. The results obtained show that physically handicapped children were not so well accepted by their peers as were their normal controls. The only characteristics which were positively related to social acceptability of the physically handicapped were certain components of emotional adjustment, extraversion and teachers' estimates of their mathematical ability. It is suggested that peer acceptance might be enhanced by greater dissemination of information and advice to both teachers and the normal peer group.

Cerebral Palsy↗
PubMed1996

Gender does not influence sympathetic neural reactivity to stress in healthy humans.

Previous data support the idea of heightened sympathetically mediated cardiovascular reactivity in males. However, definitive conclusions cannot be made because of inconsistent reports, possibly stemming from imprecise measurement of sympathetic activity and/or failure to equate the stress stimuli between genders. The present study tested the hypothesis that males exhibit heightened sympathetic reactivity that is associated with heightened cardiovascular and plasma catecholamine responses. In 37 healthy adults (20 males, 17 females: age = 20-42 yr), direct recordings of skeletal muscle sympathetic nerve activity (MSNA), plasma catecholamines, heart rate, blood pressure, and perceived stress were measured before and during three laboratory stressors (isometric handgrip, cold pressor, and mental arithmetic). MSNA, catecholamine, and cardiovascular reactivity (defined as change from rest) were not consistently different between genders. For the isometric handgrip, when expressed as absolute unit changes, males had larger MSNA responses (P < 0.01), which were partially explained by greater contraction force; they did not differ in terms of percent change from baseline or in perceived stress. The responses to the cold pressor and mental arithmetic tasks were similar between genders. These findings indicate that stress-evoked vasoconstrictor neural excitation and the associated increases in blood pressure are not consistently influenced by gender.

Adult↗
PubMed1986

Respiratory volume perception through the nose and mouth determined noninvasively.

The relative importance of the nose vs. the mouth in the perception of respiratory volumes has never been assessed, nor have previous respiratory perception studies been performed noninvasively. Using respiratory inductive plethysmography, we monitored 12 normal subjects noninvasively when breathing either exclusively through the nose or mouth. The sensation of inspired volume mouth breathing was compared with that of nose breathing over a wide range of the inspiratory capacity. The psychophysical techniques of tidal volume duplication, tidal volume doubling, and magnitude estimation were utilized. A just noticeable difference was calculated from the constant error of the tidal volume duplication trials. The exponents for magnitude estimation were 1.06 and 1.07 for nose and mouth breathing, respectively. The other psychophysical techniques also revealed no differences in nose and mouth volume perception. These results suggest that tidal volume changes are perceived equally well through the nose and mouth. Furthermore, the location of the receptors, important in volume perception, is probably at a distal point common to the nose and mouth.

Adult↗
PubMedDate not supplied

Emotional adjustment and school functioning of young adolescents with multiple versus single learning disabilities.

Early adolescents (Grades 6-8) with multiple learning disabilities (LD; reading and math) in inclusive settings were compared to adolescents with single LD (reading or math) and typically achieving (TA) peers regarding their psychosocial functioning in two areas of adolescent well-being: emotional adjustment and school functioning. The Behavior Assessment System for Children (Reynolds & Kamphaus, 1998) Self-Report of Personality for adolescents was used to determine well-being. One hundred twenty middle school students-15 boys and 15 girls in each group-were included in the current study. The results confirmed that adolescents with multiple LD (reading and math) reported poorer functioning (i.e., higher T scores) on school maladjustment, clinical maladjustment, emotional symptoms index, attitude to school, atypicality, and depression when compared to TA peers but not when compared to peers with a single LD (reading or math). All three groups differed from the TA group (but not from each other) on sense of inadequacy, with the multiple LD group reporting the highest T scores. Additional analyses indicated significant differences between girls and boys, regardless of disability status. Girls reported higher T scores on the emotional symptoms index, social stress, and depression, but boys reported greater school maladjustment and sensation seeking. Implications for practice and recommendations for future research are discussed.

Adaptation, Psychological↗
PubMedDate not supplied

The roles of experience and domain of expertise in using numerical and verbal probability terms in medical decisions.

Verbal probability terms are frequently used in medical practice. In the present experiment the use of verbal and numerical probability terms in medical decisions was investigated. Interns, residents in surgery and internal medicine, surgeons, and internists were asked to make treatment decisions for three different cases (acute appendicitis, angina pectoris, and an imaginary disease) and were also asked to give numerical interpretations of a series of verbal probability terms. In the second stage of the experiment the respondents received the same cases, but with numerical probability terms. The results showed no effect of context or of domain experience on the interpretation of verbal terms. Residents and experienced surgeons more often agreed on treatment decisions when chance information was presented in numerical terms as compared with verbal terms. Physicians were less confident when verbal terms were presented, but only for the less familiar decision problems. Finally, physicians turned out to be better in Bayesian reasoning when numerical terms were used. Experienced physicians were quite accurate in estimating the posterior probability in the appendicitis case, but not in the imaginary-disease case.

Acute Disease↗
PubMed1992

Association of attitude toward mathematics with self-efficacy, causal attribution, and personality traits.

983 children from Grades 1, 2, and 3 of the middle schools participated as subjects. Of these, 339 children were judged as having higher "self-efficacy" than the others. The associations of attitude toward mathematics with self-efficacy, attributions, and personality traits measured on the Shimoda Personality Inventory were investigated. Analysis showed that attitude toward mathematics had significant effects on mathematics performance. In attribution of effects to mathematics performance there were differences among the children across the grades. Among personality traits the immodithymic trait was significantly correlated with attitude toward mathematics.

Achievement↗
PubMed1994

Mental visualization before and after problem presentation: a comparison.

Three experiments were carried out to study the effects on problem solving of visualization when subjects (secondary-school students and undergraduates) were instructed to generate mental images before the problem was presented and when they received such a hint after being given the problem. In each experiment an arithmetic, a geometric, and a practical problem were presented in three different conditions, a control condition, an "imagery-before" condition, and an "imagery-after" condition. Analysis showed that, in general, the "imagery-after" task helps subjects to overcome the misleading or fixating tendencies which interfere with problem solution; in contrast, the "imagery-before" task may enhance such tendencies.

Adult↗
PubMed1995

Digit and shape memory function in soroban learners: are soroban learners superior in general?

The memory function of 15 soroban learners and 13 novices was examined on visual memory tasks. Analysis showed soroban learners were superior in performance of digit recall but not of shape recall. This result seems to reflect the tendency for soroban groups to be better in processing some kinds of spatial than categorical properties. Based upon these results, effects of soroban learning on brain function were discussed.

Attention↗
PubMed1996

Evidence of nonverbal learning disability among learning disabled boys with sensory integrative dysfunction.

The presumed sensorimotor basis of the nonverbal learning disability syndrome was investigated among 90 learning disabled boys (M age = 6 yr., 8 mo., SD = 12.2 mo.) with sensory integrative dysfunction. The majority of the boys were Caucasian, lower to middle socioeconomic status, and from urban, English-speaking families. 14% (n = 13) of the boys satisfied core discrepancy criteria for nonverbal learning disability, including both a significantly higher Wechsler Verbal than Performance IQ and a higher standard score in Reading than Arithmetic on the Wide Range Achievement Test. Compared with a control group of 19 boys from the same sample who had no significant discrepancies, boys with nonverbal learning disability had significantly greater weaknesses in space visualization and visuomotor coordination. As predicted, rote verbal memory and syntactical strengths were also exhibited by boys with nonverbal learning disability, but the two groups did not differ significantly.

Child↗
PubMed2006

Relationship between students' self-assessment of their capabilities and their teachers' judgments of students' capabilities in mathematics problem-solving.

The study examined the judgments made by four seventh-grade mathematics teachers of their 107 students' competence in solving mathematics problems. Simultaneously, the 107 students made self-efficacy judgments about their capability in solving mathematics problems. The two sets of judgments were tested for predicting students' mathematics performance. Also, students' prior mathematics achievement was studied for its influence on both teachers' and students' judgments and students' mathematics performance. Teachers were asked to make judgments of each student for every mathematics problem solved. Results were consistent with prior research indicating that students' mathematics self-efficacy beliefs were highly predictive of their performance. Path analysis indicated that the mathematics teachers' judgments were also highly predictive of students' performance and self-efficacy. In turn, these variables predicted students' postperformance judgments. Combining students' self-efficacy judgments and teachers' judgments of students increased predictiveness for students' mathematics performance. Educational implications were also discussed.

Achievement↗
PubMed1999

Individual solution processes while solving addition and multiplication math facts in adults.

Contrary to predictions of current solution process models, adults used a variety of procedures other than retrieval to solve addition and multiplication math facts. Predictors assumed to capture retrieval processes posited by such models did account for a substantial proportion of variance in averaged retrieval solution times. But most of the variance in individual participants' retrieval times remained unaccounted for. Cross-operation associations in patterns of strategy use and retrieval latencies were obtained. Adults with stronger higher level math achievement were more likely to use retrieval, solved math facts faster and less variably, and executed retrieval processes posited by current solution process models faster than participants with less math attainment. The results are explained within the context of the adaptive strategy choice model.

Adult↗
PubMed1989

Effects of calculator use on arithmetic and conceptual skills of nursing students.

The purpose of this study was to determine the effect of the use of calculators on the responses of undergraduate nursing students to items on a dosage calculations examination. The study sought to determine if calculator use had any influence on both the arithmetic and conceptual skills associated with the solving of calculations problems. The population consisted of all students enrolled in a pharmacology course in a baccalaureate nursing program. An experimental repeated measures design was used in which all participants completed two parallel forms of a calculations examination, one form with a calculator and one form without a calculator. Findings of the study revealed that there was significant difference in both arithmetic and conceptual skills ability using a calculator. Use of a calculator was associated with improved arithmetic skills performance and diminished conceptual skills performance. A major factor underlying both arithmetic skills and conceptual skills performance, independent of the calculator effect, was the pre-admission arithmetic skills ability of the subject.

Concept Formation↗
PubMedDate not supplied

[The patterns in the molecular biology of the adenoviruses (the results of a 20-year study at the Institute of Microbiology and Virology of the National Academy of Sciences of Ukraine)].

Scientific data of the highest importance and priority concerning regularities of structural and functional organization of proteins of adenoviruses capsids and peculiarities of expression of the virus genome are as follows: New antigen determinants of hexon and adenovirus fiber have been discovered, their different nature (conformational or linear) and different orientation, depending on the spatial organization of proteins, have been proved; localization of some epitopes has been determined with the help of synthesised antigen-active peptides, imitating them. Some regularities of structural and functional organization of adenovirus hexon have been determined on the basis of comparative analysis of antigenic specificity and primary structure of proteins being apart in taxonomic respect. The conception of immunoactivation (infectivity neutralization) of adenoviruses has been developed, and a mathematical model of this process has been first proposed, which determines the impact of antibodies to several antigenic determinants of hexon and fiber as well as interferon and complement. The unknown peculiarities of the adenovirus genome expression were studied in the dynamics of productive infection or under the effect of modified nucleosides, proteolysis inhibitors and those of different nature promising for chemotherapy of adenovirus infection. Lymphotropicity of adenoviruses was established and a model of the mixed infection of lymphocytes with adenoviruses, HIV, and Epstein-Barr virus of the herpes virus family was proposed for the first time. It was determined that the mutual interference of viruses was developed at the process of a single or successive infection and this was important to understand AIDS immunopathogenesis. Data presented substantiate the ways of creation of modern efficient preparations for diagnosis, prophylaxis and chemotherapy of adenovirus infection.

Adenoviridae Infections↗
PubMed2000

Adequacy in dialysis: intermittent versus continuous therapies.

A vital conceptual difference between intermittent and continuous dialysis therapies is the difference in the relationship between Kt/V urea and dietary protein intake. For a given level of protein intake the intermittent therapies require a higher Kt/V urea due to the reasons mentioned above. The recently released adequacy guidelines by DOQI for intermittent and continuous therapies are based on these assumptions. The link between adequacy targets and patient survival is well documented for an intermittent therapy like HD. For a continuous therapy like CAPD however, the evidence linking improved peritoneal clearance to better survival is not as direct. However, present consensus allows one to extrapolate results based on HD. The concept of earlier and healthier initiation of dialysis is gaining hold and incremental dialysis forms an integral aspect of the whole concept. Tools like urea kinetic modeling give us valuable insight in making mathematical projections about the timing as well as dosing of dialysis. Daily home hemodialysis is still an underutilized modality despite offering best survival figures. Hopefully, with increasing availability of better and simpler machines its use will increase. Still several questions remain unanswered. Despite availability of data in hemodialysis patients suggesting that an increased dialysis prescription leads to a better survival, optimal dialysis dose is yet to be defined. Concerns regarding methodology of such studies and conclusions thereof has been raised. Other issues relating to design of the studies, variation in dialysis delivery, use of uncontrolled historical standards and lack of patient randomization etc also need to be considered when designing such trials. Hopefully an ongoing prospective randomized trial, namely the HEMO study, looking at two precisely defined and carefully maintained dialysis prescriptions will provide some insight into adequacy of dialysis dose and survival. In diabetic patients, the relationship between outcome and dialysis dose needs to be better defined. Data relating adequacy of dialysis to outcome in a pediatric population is not available. In dialysis therapy, the Risk/Dose (R/D) function does not bear a linear relationship. This together with a lack of proof equating peritoneal to renal clearance lends some uncertainty to the validity of the recommendation that there is a linear and constant decrease in RR for std (Kt/V) [equivalent standardized Kt/V calculated from average predialysis BUN for any frequency and/or combination of intermittent and continuous dialysis ref] up to 2.3 as reported in the CANUSA study. Due to the complex nature of this problem it may be prudent to undertake a multi-center trial with std (Kt/V) prospectively randomized to either 2.0 or 2.4. This would provide a reliable database to evaluate the R/D function over this critical range of normalized peritoneal urea clearance. Likewise in PD, the postulated linearity between dialysis dose and outcome needs to be studied in a prospective randomized manner. The amount of dialysis dose required for malnourished patients, diabetic and pediatric patients needs to be better defined. The role of aggressive dialysis in reversing malnutrition needs to be studied and studies need to be done to identify the most scientific use of V in malnourished patients. Justification of a healthy start/incremental dialysis based on outcome measures needs to be established and it's cost effectiveness validated by clinical trials. Again, a prospective randomized controlled trial comparing incremental dialysis with dietary protein restriction in patients with GFR < or = 10.5 ml/min/1.73 m2 with properly defined outcome measures like morbidity, mortality, decline of GFR and quality of life needs to be conducted. Comparisons of incremental hemodialysis and incremental peritoneal dialysis need to be made especially with regard to technique survival and preservation of residual renal function (RRF). (ABSTR

Dietary Proteins↗