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La predazione negli uccelli rapaci
No full textIl comportamento degli uccelli rapaci è stato lungamente studiato da vari punti di vista, ma principalmente ecologici: i rapporti preda-predatore, le preferenze alimentari, il comportamento riproduttivo in senso lato, i rapporti interspecifici con altri rapaci, il riconoscimento della preda e l'eventuale formazione dell'immagine di ricerca (ad es. Beissinger, 1983; Mueller, 1987; Widèn et al., 1987; Korpimäki, 1992). Molto poco, invece, è stato fatto per indagare il comportamento predatorio vero e proprio nei confronti soprattutto di prede terrestri, cioè l'analisi delle singole parti formanti la sequenza predatoria, che si inizia con il riconoscimento della preda e termina con la sua ingestione. Un tale studio è molto difficile da compiersi in ambiente naturale, a causa soprattutto dell'occasionalità nell'osservazione del singolo evento predatorio e della grande distanza di fuga che i rapaci mostrano quando si trovano a terra con la preda appena catturata.
L'ormai diffusa presenza di Centri di recupero per uccelli rapaci ha permesso di effettuare una serie di esperimenti, alcuni dei quali vengono illustrati in questo contributo, condotti in una situazione standardizzata di laboratorio e con campioni statistici di apprezzabili dimensioni, condizioni, queste, che ben difficilmente si riesce ad ottenere in natura. Si è voluto analizzare in dettaglio il comportamento predatorio e alcune variabili che potenzialmente ne influenzano l'esplicazione, con particolare riguardo agli stimoli provenienti dalla preda, l'influsso sia della durata della cattività che dell'esperienza predatoria al momento del test di predazione
Role of experience and maturation in barn owl predatory behaviour
No full textThe predatory behaviour on mice by sample of seventeen captive barn owls (Tyto alba) was studied. The owls were divided into two groups according to their age when they entered the Rehabilitation Centre used for this study (either adults/subadults, i.e., with previous predatory experience in the wild, or as fledglings, without any experience of prey catching). The few differences between the behaviour patterns of the age groups suggested that predatory behaviour is mostly under genetic control. While most adult birds caught the mouse, only four young out of eleven studied did so. Both groups showed a decreasing trend in the latency of predation. The young birds were confused or in conflict when facing the prey, and in some cases the owl approached the mouse closely and then returned to the perch to begin a complete predatory sequence again. Three young birds of those that did not hunt were tested six months later. Two of these three young caught a mouse without any evident difficulty. The behaviour displayed by young birds and some patterns indicate that a maturation process is likely influencing the development of the predatory tendency, and do not fully support the hypothesis of the existence of some temporally well-defined periods
La predazione negli uccelli rapaci
No full textIl comportamento degli uccelli rapaci è stato lungamente studiato da vari punti di vista, ma principalmente ecologici: i rapporti preda-predatore, le preferenze alimentari, il comportamento riproduttivo in senso lato, i rapporti interspecifici con altri rapaci, il riconoscimento della preda e l'eventuale formazione dell'immagine di ricerca (ad es. Beissinger, 1983; Mueller, 1987; Widèn et al., 1987; Korpimäki, 1992). Molto poco, invece, è stato fatto per indagare il comportamento predatorio vero e proprio nei confronti soprattutto di prede terrestri, cioè l'analisi delle singole parti formanti la sequenza predatoria, che si inizia con il riconoscimento della preda e termina con la sua ingestione. Un tale studio è molto difficile da compiersi in ambiente naturale, a causa soprattutto dell'occasionalità nell'osservazione del singolo evento predatorio e della grande distanza di fuga che i rapaci mostrano quando si trovano a terra con la preda appena catturata.
L'ormai diffusa presenza di Centri di recupero per uccelli rapaci ha permesso di effettuare una serie di esperimenti, alcuni dei quali vengono illustrati in questo contributo, condotti in una situazione standardizzata di laboratorio e con campioni statistici di apprezzabili dimensioni, condizioni, queste, che ben difficilmente si riesce ad ottenere in natura. Si è voluto analizzare in dettaglio il comportamento predatorio e alcune variabili che potenzialmente ne influenzano l'esplicazione, con particolare riguardo agli stimoli provenienti dalla preda, l'influsso sia della durata della cattività che dell'esperienza predatoria al momento del test di predazione
Archiviazione automatica dei dati isto-citopatologici: sistema operativo in atto presso l'Istituto di Anatomia ed Istologia patologica di Trieste
No full textAssessing mother-to-infant attachment: the Italian adaptation of a self-report questionnaire
No full textThe mother-to-infant relationship is usually assessed by behavioural observation. In order to evaluate mothers’ emotional and cognitive response to their infants, Condon and
Corkindale [(1998) The assessment of parent-to-infant attachment: development of a selfreport questionnaire instrument, Journal of Reproductive and Infant Psychology, 16, 57–76] have developed a self-administered questionnaire. The aim of the present study is the Italian validation of the scale. The questionnaire contains 19 items each rated on a 5-point
scale. A sample of women with infants between 2 and 4 months of age were recruited at two postnatal wards in Genoa (Italy). Construct validity was assessed by administering two additional questionnaires: the Symptom Rating Test by Kellner and Sheffield and the Early Infancy Temperament Questionnaire by Medoff-Cooper, Carey and Mc Devitt. A total of 210 women were evaluated. The distribution of scores tended to be skewed towards higher attachment scores and the range was 59 to 95. The mean of the total scale was 81.5 (SD~6.5) and Cronbach’s alpha was 0.77. Attachment scores were negatively correlated
with all the Symptom Rating Test subscales (r between 20.23 and 20.37; pv0.01).
Mothers of children with difficult temperament had lower attachment scores (t~22.780; pv0.01). Factor analysis revealed six factors which accounted for 57% of the variance. The psychometric properties of the Italian version of the scale were similar to those of the original version. The three-factor structure found by Condon and Corkindale was not confirmed in the Italian version. The scores on the scale relate to other variables in a way that is consistent with attachment literature
Adattamento e validazione in italiano di un questionario autocompilato per la valutazione del legame di attaccamento madre-bambino
No full text
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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