Analysis of an advisor-advisee relationship: an exploratory study of the area of exact and Earth sciences in Brazil.

Scientific collaboration has been studied by researchers for decades. Several approaches have been adopted to address the question of how collaboration has evolved in terms of publication output, numbers of coauthors, and multidisciplinary trends. One particular type of collaboration that has received very little attention concerns advisor and advisee relationships. In this paper, we examine this relationship for the researchers who are involved in the area of Exact and Earth Sciences in Brazil and its eight subareas. These pairs are registered in the Lattes Platform that manages the individual curricula vitae of Brazilian researchers. The individual features of these academic researchers and their coauthoring relationships were investigated. We have found evidence that there exists positive correlation between time of advisor-advisee relationship with the advisee's productivity. Additionally, there has been a gradual decline in advisor-advisee coauthoring over a number of years as measured by the Kulczynski index, which could be interpreted as decline of the dependence

Risk factors for birth-related perineal trauma: a cross-sectional study in a birth centre

Aim and objectives. To identify maternal, newborn and obstetric factors associated with birth-related perineal trauma in one independent birth centre. Background. Risk factors for birth-related perineal trauma include episiotomy, maternal age, ethnicity, parity and interventions during labour including use of oxytocin, maternal position at time of birth and infant birth weight. Understanding more about these factors could support the management of vaginal birth to prevent spontaneous perineal trauma, in line with initiatives to reduce routine use of episiotomy. Design. Cross-sectional study. Methods. Data were retrospectively collected from one independent birth centre in Brazil, during 20062009. The dependent variable (perineal trauma) was classified as: (1) intact perineum or first-degree laceration, (2) second-degree laceration and (3) episiotomy (right mediolateral or median). Results. There were 1079 births during the study period. Parity, use of oxytocin during labour, position at time of giving birth and infant birth weight were associated with second-degree lacerations and episiotomies. After adjusting for parity, oxytocin, maternal position at the expulsive stage of labour and infant birth weight influenced perineal outcomes among primiparae only. Conclusions. Although the overall rate of episiotomies in this study was low compared with national data, it was observed that younger women were most vulnerable to this intervention. In this age group in particular, the use of oxytocin as well as semi-upright positions at the time of birth was associated with second-degree lacerations and episiotomies. Relevance to clinical practice. The use of upright alternative positions for birth and avoidance of use of oxytocin could reduce the risk of perineal trauma from lacerations and need to perform episiotomy

Distribution of the time to the first publication with and without the advisor (<i>z</i>_<i>i</i> and zi*) for Exact Sciences.

<p>Distribution of the time to the first publication with and without the advisor (<i>z</i>_<i>i</i> and </p><p></p><p></p><p></p><p><mi>z</mi><mi>i</mi><mo>*</mo></p><p></p><p></p><p></p>) for Exact Sciences.<p></p

Proportion of A-A publications with regard to the total number of publications of the advisee (<i>q</i>_<i>y</i>) for the Exact Sciences.

<p>Proportion of A-A publications with regard to the total number of publications of the advisee (<i>q</i>_<i>y</i>) for the Exact Sciences.</p

Frequency distribution of the number of years to obtain the PhD degree (TiC) for Exact Sciences by decades.

<p>(D1 = 1981–1990, D2 = 1991–2000 and D3 = 2001–2010).</p

Number of researchers, number of advisor-advisee pairs and number of publications for each subarea.

<p>Number of researchers, number of advisor-advisee pairs and number of publications for each subarea.</p

Proportion of A-A publications with regard to the publications of the advisee (<i>q</i>_<i>y</i>) for decade D3 for the Exact Sciences and the five clusters per subareas (according to the dendrogram).

<p>Proportion of A-A publications with regard to the publications of the advisee (<i>q</i>_<i>y</i>) for decade D3 for the Exact Sciences and the five clusters per subareas (according to the dendrogram).</p

Proportion of advisees without A-A publications by decades.

<p>Proportion of advisees without A-A publications by decades.</p

Mean of the Kulczynski index for decade D1, decade D2 and decade D3 for the Exact Sciences and the five clusters per subareas (according to the dendrogram).

<p>Mean of the Kulczynski index for decade D1, decade D2 and decade D3 for the Exact Sciences and the five clusters per subareas (according to the dendrogram).</p