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The performance of Octopus cyanea was studied in 3 appetitive conditioning situations. In Experiment 1, 2 groups were trained in a runway ; a large reward produced faster acquisition when reinforcement was consistent and better subsequent performance on a partial schedule than did a small reward. In Experiment 2, activity in the vicinity of a feeder was measured, and in Experiment 3, latency and probability of response were measured in an automated version of a traditional conditioned attack situation (Boycott & Young, 1950). There was evidence of acquisition with continuous reinforcement in both experiments but in neither with partial reinforcement. All of the results can be understood in terms of growth and decline in the strentgh of stimulus-reinforcer associations with reinforcement and nonreinforcement

Ivomec in drinking water at dilutions of 1 ml/l (10 micrograms of Ivermectin/ml), 2.5 ml/l (25 micrograms of Ivermectin/ml) and 5 ml/l (50 micrograms of Ivermectin/ml) was successful against Myobia musculi and Myocoptes musculinus mange in naturally infected laboratory mice after 4 consecutive treatment days. One day before treatment drinking water was withheld. Ivermectin solutions were administered ad libitum.

The relationship of familial, demographic, and individual characteristics to the probability of pregnancy was examined among 124 sexually active adolescent females. Logistic regression analyses revealed that adolescent pregnancy status was a function of a combination of demographic and familial variables. Adolescents who were pregnant at the time of the study perceived their families as having low levels of family strength, perceived communication with parents as closed, came from homes characterized by family fragmentation (i.e., only one parent or no parent living in the home), came from low-income households, were unlikely to use any method of birth control, and were more likely to be married than their nonpregnant counterparts.The differences in demographic characteristics, sexual practices, perceptions of family functioning, and individual factors among pregnant and nonpregnant adolescents were studied. 124 sexually active adolescent Caucasian females aged 12-19 years from an Arkansas clinic of which 57% were pregnant, participated in a nonrandom sample in 1988-89. 62.1% were from disrupted families (39.5% divorced, 12.9% remarried, and 9.7% widowed). Family disruption was higher among the pregnant sample (72% vs. 50.8%). 16.9% of the total sample were high school dropouts, but the majority were in the pregnant sample (28% vs. 5%). 91% of the pregnant sample had a family income of $20,000 vs. 66% of the nonpregnant sample. The procedures and instruments used are described. The following questionnaires were involved: 1) a demographic questionnaire for age, race, educational and marital status, parents' marital status, and socioeconomic status; 2) a sexual history questionnaire for pregnancy status, use of birth control, prior pregnancies and outcomes, and frequency of sexual activity; and 3) the Family Adaptability and Cohesion Evaluation Scale, the Family Strengths Questionnaire, the Parent Communication Scale, and the Adolescent Self-Esteem Scale. Stepwise logistic regression and chi square tests were used to predict pregnancy status. 6 variables out of 11 were significantly related to pregnancy status: lower perception of family strengths, problems with parent communication, married, low family income, birth control, and single parent or no parent family composition. 80% of pregnant and nonpregnant teens were predicted. The mean for perception of family strengths for pregnant vs. nonpregnant adolescents was 33.29 vs. 39.87, which means for pregnant teens a perception of a lack of pride and harmony in their families. Lower scores were also evident on the Parent Communication Scale (-1.22 vs. 2.62). Although not significant, pregnant adolescents saw their families as flexible but not very cohesive and had lower self-esteem scores. Nonpregnant adolescents were more likely to use birth control than pregnant adolescents. The results support prior findings with some variation in the effect of parent and child communication, and insignificant effects of perception of family adaptability, and self-esteem. The limitations are the lack of generalizability to other regions, and the model itself which did not assess familial factors such as parental control or other developmental factors such as self-worth. Causality is not determined.

B. transfuga larvae migrated in livers, lungs and brains of experimentally infected mice. B. transfuga larvae have never been reported as etiologic agents of visceral larva migrans, but our results show that they have a migration in experimental paratenic hosts of a type that suggests their possible role in this syndrome.

The assumption that classical conditioning depends on a contingent relation between the conditioned stimulus (CS) and the unconditioned stimulus (US), which was proposed some decades ago as an alternative to the traditional contiguity assumption, still is widely accepted as an empirical generalization, if no longer as a theoretical postulate. The first support for the contingency assumption was provided by experiments in which occasional CS-US pairings produced no response to the CS in random training--i.e., training in which the probability of the US was the same in the presence and absence of the CS. Those early experiments, the results of which too often are taken at face value, are reconsidered along with various later experiments that show conditioning, both of the CS and its context, in random training. The evidence suggests that CS-US contingency is neither necessary nor sufficient for conditioning and that the concept has long outlived any usefulness it may once have had in the analysis of conditioning.

Book Review Spontaneous alternation behavior edited by W. N. Dember & C. L. Richman. Springer-Verlag, New York, 1990, XII + 211 pp.

A total of 178 subjects participated in a study designed to assess whether adolescent perceptions of intrapsychic and extrapsychic functioning could be used to discriminate between pure identity statuses. Intrapsychic functioning was dimensionalized to include the degree of self-conscious reasoning, and the quality of the separation-individuation process of adolescence. Extrapsychic functioning was dimensionalized in terms of family coping, family cohesion, and openness of parent-adolescent communication patterns. The stepwise discriminant analysis yielded two discriminant functions which indicated that the adolescent's perceptions of intrapsychic and extrapsychic functioning significantly discriminated between the identity statuses. The classification results reveal that identity achieved and diffused adolescents were most accurately identified based on the discriminant functions. The discussion addresses the relevance of these findings to the model of adolescent psychosocial development advanced by Grotevant and Cooper.

This research attempted to more adequately dimensionalize the study of affective family relations during adolescent pubertal maturation by employing a multivariate approach. Fifty-one families responded to an assessment battery consisting of a series of questionnaires designed to measure affective relations between parents and their adolescent children. Families were classified into prepubertal, transpubertal, or postpubertal groups according to their modal response on pubertal status criteria. A stepwise discriminant analysis was performed to identify measures that maximize between groups differences. Based on this analysis, a correct classification rate of 70% was achieved for all families. The two significant discriminant functions that emerged indicate that differences in family relationships are due to the transformation of mother-adolescent and father-adolescent relations. The pattern of results replicate those of other researchers and provide elaborations concerning the affective nature of family relations during adolescence.

The recent literature on human sexuality emphasizes the importance of sexual communication. The present research reports the results of three studies documenting the development and validation of an instrument concerned with sexual communication, the Sexual Self-Disclosure Scale (SSDS). The results in Study I indicated that the twelve SSDS subscales were highly reliable and that women were more willing to discuss the topics on the SSDS with female than male therapists. A second study revealed that men's and women's responses to the SSDS were related in meaningful, predictable ways to their sexual-esteem, sexual-depression and sexual-preoccupation, as measured by the Sexuality Scale. In Study III, the SSDS was revised to include a wider variety of sexual topics dealing with sexual behaviors, values-preferences, attitudes, and feelings. The results from Study III indicated that men's and women's responses to the SSDS-R varied as a function of their own gender and the content of the sexual topics. The discussion focuses on the increased need for communication about sexual issues, the implications of the present findings for intimate relationships, and the possible uses of the Sexual Self-Disclosure Scale in the study of human sexuality.

Two experiments with rats explored the role of reinforcing events in the acquisition of a behavioral sequence. The sequence involved running from the start box to the goal box of a T maze (initial response, IR) to obtain a reward, and returning to the start box after consuming the reward (the final response, FR). In Experiment 1, rats were trained in a differential-outcomes conditional discrimination with sucrose solution and food pellets as rewards. A consistent relationship between the conditional stimulus and the reward type enhanced acquisition of both the IR and the FR, relative to a nondifferential control group. In Experiment 2, the length of the intertrial interval was varied according to the number of errors in the FR: less than two errors led to a 5-min interval, whereas two errors or more led to a 15-s interval. Rats submitted to this contingent treatment showed an increment in errors in the FR in comparison to yoked controls. The results indicated that reinforcing events may have various simultaneous effects upon different components of a response sequence.

In a consummatory experiment patterned after previous work with rats and goldfish, successive negative incentive contrast was sought in didelphid marsupials of two species (Lutreolina crassicaudata andDidelphis albiventris). Half of the subjects of each species were trained from the outset with a 32% sucrose solution and shifted occasionally to a 4% sucrose solution; the rest, which served as controls, were trained only with the 4% solution. The positive results obtained (less response to the 4% solution in the shifted subjects than in the controls) fit the hypothesis, based on comparative work with descendants of older vertebrate lines, that the mechanism of successive negative incentive contrast evolved in a common reptilian ancestor of birds and mammals.

The effects of simultaneous and serial bilateral ablation of the goldfish telencephalon on the retention of an avoidance response was studied. On the basis of research in mammals, it was expected that the serial procedure would produce significant savings in the retention of avoidance learning, which is otherwise significantly impaired after simultaneous bilateral ablations of the telencephalon. The retention of the avoidance task learned prior to the ablations was unaffected by the serial procedure.

The purpose of this study was to describe the role of affective and assertive interactions in familial adaptation to adolescent pubertal development. Twenty-five family triads consisting of the adolescent and parents were asked to engage in an Unrevealed Differences task. This interaction was audiorecorded, and statements were coded as affective or assertive using a modified version of Bales's ([1970) Personality and Interpersonal Behavior, Holt, Rhinehart and Winston, Inc., New York) Interaction Process Analysis. Family relationships appear redefined during transpuberty, a time when physical changes associated with the onset of puberty are at apeak. This redefinition of transpubertal family relations is characterized by a decline in the use of affective statements coupled with an increase in the use of assertive statements relative to prepubertal and postpubertal families. Differences in mother-adolescent and father-adolescent interactions also are discussed.

This article describes the development of the Sexuality Scale, an instrument designed to measure three aspects of human sexuality: sexual‐esteem, defined as positive regard for and confidence in the capacity to experience one's sexuality in a satisfying and enjoyable way; sexual‐depression, defined as the experience of feelings of depression regarding one's sex life; and sexual‐preoccupation, defined as the tendency to think about sex to an excessive degree. The procedure involved (a) item construction, selection and subsequent validation through item analysis; and (b) a factor analysis of the items on the Sexuality Scale and the establishment of factorial validity. The results indicated that the three subscales were psychometrically sound, that males reported more sexual‐preoccupation than did females, and that the three subscales have unique intercorrelation patterns. The exploratory nature of these findings are discussed.

The purpose of this study was to describe domains of family conflict and to examine variations in these domains by adolescent pubertal status, gender, and status as a family member. Sixty-three intact family triads completed an instrument designed to assess pubertal status and the Issues Checklist. Principal Factor Analysis with Varimax rotation resulted in the retention of seven factors accounting for 78.52 percent of the variance. Separate Stepwise Regression analyses were conducted for each factor (using factor scores) with adolescent pubertal status, gender, and status as a family member as predictors. Persistent Concerns and Appearance Issues were more disruptive in families with daughters than sons. Room Care and School Issues varied among family members. Leisure and Time Management Issues varied by adolescent pubertal status. Only Household Issues were unrelated to any of the predictor variables. In summary, the affective climate of the family can be characterized by a variety of conflictual domains, the intensity of which are related to adolescent pubertal status, gender, the role as a family member.

A study was conducted to examine adolescent's sexual self-disclosure to their parents and friends. The sample consisted of 169 senior high school students. The results revealed that adolescents engage in more sexual disclosure with their friends than with their parents. In addition, significantly greater sexual disclosure was reported between adolescents and same-sex, rather than opposite-sex, parent and friend. The only exception to this finding was that no significant differences were reported in male and female sexual self-disclosure to a best female friend. Additional regression analyses revealed that adolescent sexual disclosure to parents was strongly associated with adolescent perceptions of the openess and adaptiveness of the family context. By contrast, sexual disclosure to friends was strongly related to the adolescent's emotional individuation from the family. The discussion focuses on sexual socialization during adolescence.

Choice behavior of the armadillo Chaetophractus villosus (Edentata, Dasypodidae) was studied under laboratory conditions. Two groups were trained in a simultaneous visual discrimination task with food-reward. One group was trained with a contiguous spatial-temporal relationship between the discriminative stimulus and the reinforcement. For the second group, a spatial-temporal separation of these relevant stimuli was imposed in order to lengthen the presolution period. Attention was directed at determining which one of four positional strategies (alternation, position habit, win-shift/lose-stay, and win-stay/lose-shift) prevailed during the acquisition of the discrimination. There were no obvious differences in choice strategies between the groups, although the immediate spatial-temporal contiguity between the discriminative and reinforcing stimuli produced a significantly faster acquisition. Position habit was the only spatial strategy consistently observed between animals and maintained for a va...

The purpose of this study was to examine the relationship between adolescent pubertal status, the affective quality of family relations, and the early adolescent's exploration of a sense of ego identity. Fifty-one intact families with adolescents in the seventh grade agreed to participate. Each family member completed a battery of questionnaires designed to assess familial adaptation to pubertal growth and identity exploration. The results reveal that the affective quality of parent-adolescent relationships and the pubertal status of the adolescent appear to influence the adolescent's exploration of ego identity. The need to establish the functional significance of familial adaptation to adolescent pubertal growth for identity development is discussed.

Investigations of children's selective attention and problem-solving abilities demonstrate clear developmental trends towards greater efficienq in visual search strategies with age (3). Other investigators have suggested that individual differences within age groups may affect visual attention and other information-gathering processes (1). The present study was designed to investigate the effects of sex, age, and cognitive style on the visual-search strategies required to locate stimulus discrepancies. Forty children were assigned to one of eight groups on the basis of age, sex, and cognitive style. The mean ages of younger and older children were 3.14 and 4.92 yr., respectively. The apparatus allowed presentation of slides of familiar figures, and each child was tested individually in a single session (2). Pre-task slides were employed, and the child was taught to locate and point to the end of figures where the differences were located. Errors were followed by verbal correction from the experimenter. (The trial tasks were the same.) The dependent variables (total looks, middle looks, and nonhomologous, homologous, and informative homologous comparisons. Homologous comparisons were defined as those looks to suucturally corresponding stimulus parts), were examined in an analysis of variance. The reliability for all data on each subject averaged 91 %. The results indicate chat older children looked more at the figures than younger children (p1.32 29.92, p < .001) and took longer to locate differences (P1.32 = 4.83, p < .05) but made fewer errors in locating differences than did younger children (P1.n~ = 61.02, P < .001). See Table 1. The older children also made more of all three types of visual comparisons than did younger children: nonhomologous (F1.31 = 10.27, P < .005), informative homologous (PI.= = 6.79, p < .025), and homologous (R.32 = 15.83, p < .001). Younger children tended to look more at the uninformative middles of the figures than did older children (P1,sa = 8.50, P < .01). The main effects for cognitive style indicated that reflective children made fewer errors in locating differences than impulsive children (P1,na = 6.63, P < ,025). Reflective children also made more homologous comparisons than impulsive children (R.32 = 4.50, p < .05). The main effects of sex showed g~rls made more homologous comparisons than boys (Pi.= = 5.83. 9 < .025). - Significant main effects for these three variables were also found for the proportion of informative homologous comparisons per stimulus: style (P1.31 = 7.10, p < .025)

The purpose of this study was to describe adolescent perceptions of conflictual family issues, and to ascertain if the intensity of these issues is associated with adolescent grade in school, pubertal status, and gender. The sample was comprised of 279 junior high and senior high school students. Each participant completed a self-report measure of pubertal status, a demographic questionnaire, and the Issues Checklist. Principal factor analysis with varimax rotation of the Issues Checklist resulted in the retention of four factors accounting for 71.59% of the variance. Stepwise regression analyses were conducted for each emergent factor with grade in school, pubertal status, and gender serving as predictors. The results of these analyses indicated that the intensity of School Issues and Household Behavior Issues is greater among seventh and ninth graders than among eleventh graders. Self-Responsibility Issues were perceived as being most intense among transpubertal adolescents. Finally, boys perceived more intense conflict over Persistent Issues and Concerns than did girls.

Summary This experiment compares spatial learning in the South American opossum (Didelphis albiventris) and armadillo (Chaetophractus villosus) in a Y-maze. Ss learned to turn to one arm of the maze for food reinforcement. To earn further reinforcements, they had to return to the start-box (after consuming the food) where they were restrained for a fixed intertrial interval. The number of entries to the unbaited arm en route to the goal-box (Ri errors), and in the way back to the start-box (Rf errors) were the dependent measures. Opossums and armadillos did not differ in Ri errors. However, only armadillos mastered the task of returning directly to the start-box after each reinforcement. Moreover, a significant within-session improvement in Rf errors was observed in armadillos, but failed to appear in opossums. Results are discussed in terms of species differences in sensitivity to temporal delays.

I Manuali curati dall’Associazione Medici Endocrinologi (AME) sono pensati per scopi pratici e sono destinati a chi, medico o infermiere, opera nell’ambito dell’endocrinologia clinica, per potersi orientare nell’ambito dei vari esami diagnostici nel campo delle malattie tiroidee. I manuali sono concepiti come documenti”bed-side” di rapida consultazione contenenti informazioni aggiornate corrette e complete. Sono consultabili al sito web dell’AME http://www.associazionemediciendocrinologi.it/TprobclinicheI109.html In linea con gli altri Manuali curati da AME, anche questo è stato pensato per scopi pratici ed è destinato a chi, medico o infermiere, opera nell’ambito dell’Endocrinologia Clinica. Non è un Testo né tantomeno un Trattato, ma uno strumento “bed-side”, semplice e di rapida consultazione. Semplicità non vuol dire superficialità, e si è posta attenzione alla completezza delle informazioni e alla loro correttezza. Lo scopo è fornire uno strumento per potersi orientare nell’ambito dei vari esami diagnostici nel campo delle malattie tiroidee, e precisare le modalità con le quali questi devono essere eseguiti. Ancora più importante, per ogni esame è descritto il significato che ha, con i limiti oltre i quali l’interpretazione diventa impropria. Non tutti gli esami sono di uso corrente, e ognuno nel proprio ambiente di lavoro sceglierà e affinerà quelli che più risultano utili in base alle esigenze locali. Nessun esame diagnostico di per sé è sufficiente per formulare una diagnosi compiuta: questo è compito del clinico, che deve integrare tutte le informazioni disponibili. Secondo un principio importante della Evidence-Based Medicine, il clinico pone una probabilità pre-test di malattia, stima cioè una probabilità di base che il paziente abbia o non abbia la malattia. Conoscendo le caratteristiche del test diagnostico che si applica, è possibile raggiungere una probabilità posttest che il più possibile aiuti a confermare o escludere la presenza della patologia. La prima sezione tratta brevemente fisiologia, fisiopatologia ed interferenze farmacologiche, la seconda i quadri clinici relativi alle malattie tiroidee. Nella terza vengono illustrati estesamente significato, modalità e interpretazione delle procedure biochimiche, ormonali, dei test dinamici e degli esami strumentali. La quarta parte è il manuale infermieristico pratico, con tutti i dettagli relativi all’esecuzione degli esami ed alla gestione dei pazienti. La quinta parte tratta i problemi metodologici relativi all’uso del laboratorio in endocrinologia, fornisce le flow-chart diagnostiche, elenca formule di uso comune e fattori di conversione tra unità di misura. I diversi capitoli sono facilmente raggiungibili scorrendo le indicazioni (di diverso colore) poste sul margine esterno del volume: in breve tempo chi lo utilizza troverà a colpo sicuro ciò che cerca.