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Changes in seasonality of birth rates in Germany from 1951 to 1990.
No full textPIP: Annual birth rates have been found to be affected up to 10-20% by seasonal variation. Variations affecting birth patterns are attributed to biological and social factors: annual rhythms of climatic conditions, or the photoperiod and varying sexual activity. A recent study placed greater priority on biological factors as responsible for seasonal variation: annual variations in sperm quality, serum levels of luteinizing hormone and testosterone in men, and ovulation variations in women by time of day. Seasonal variations in birth rates were found in Munster, Germany, between 1890-99, 1965-74, and 1981-90. Further examination was made to ascertain whether the variations pertained to the entire country of Germany. Data were obtained on monthly birth rates from 1951 to 1990 from the states of the former West Germany. Annual means were calculated and the monthly deviations from the mean computed (centered moving average with a window size of 13 months), as well as monthly means within 5-year intervals. Yearly cosine functions with 2 harmonics were also fitted to the data. The results showed maximum births in the first half of the year between 1951-75 and later months in the following years until stabilization after 1981. The amplitudes of the rhythms declined from 1972 until stabilizing and increasing after 1978. The annual patterns were smooth and stable with peaks in February and March, and a "shoulder" peak in September, which conforms to long suspected seasonal conceptions in December. The annual rhythms appear to support biologic seasonal variation until 1970. The shift after 1970 to conceptions in the winter months for Germany has also been observed with US data since 1950, and in southern hemisphere countries. The explanation may be environmental changes. The workplace environment has replaced the photoperiod influences and temperature fluctuations, but the shift by 6 months would not support this deseasonalization hypothesis. It is suggested that social reasons have affected the shift, such as the enactment of the liberal abortion law in 1976 and the pregnant woman employment protection act of 1968
RE “Invited commentary: electromagnetic fields and cancer in railway workers”. EMF dosimetry by geography. Beyond black box epidemiology
No full textGoing Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Is light a risk factor for internal cancers? – Rationale for a study based on light dosimetry by geography
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Variations on the Author
Get PDF“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
Get PDFWe 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
Estimation of immunoreactive testicular androgen metabolites in the urine of saddle-back tamarins
No full textDispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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