Thesis--University of Illinois. / Vita. Bibliography: leaves 112-118. Also issued in print.

Thesis (Ph. D.)--University of Maryland, 1991. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 348-363).

Thesis--University of Illinois. / Vita. eContent provider-neutral record in process. Description based on print version record. Bibliography: leaves 112-118.

This study examined the prevalence of information epidemics in the physics literature. The primary interest was to find out whether outliers observed on time series charts of literatures are due to information epidemics, whether these epidemics are widespread occurrences in physics, whether literatures showing such rapid growth arise mainly due to the influence of an important work and, if so, what characterizes these literatures. Information epidemics were defined as spurts of growth in the literature of a field that reflect a sudden excitement and increase in activity. It was hypothesized that information epidemics are common occurrences in the growth of the physics literature and that outliers observed during the growth of a field are caused by influential works that attract new workers into it and cause them to publish extensively. Growth spurts where information epidemics lead to a permanent change and the emergence of a new subspecialty are termed knowledge epidemics. / The monthly number of abstracts indexed by each chapter of Physics Abstracts between 1977 and 1987 was plotted on a time series chart and an envelope of +/-3 standard deviations was fitted around the regression line. All spikes that crossed the envelope were considered to be outliers and thus potential information epidemics. The abstracts contained in each outlier were identified in the Science Citation Index and analyzed for spread (corporate sources of authors) and impact (citations). / Results show that information epidemics exist, but they are not widespread. Only four information epidemics were identified in the data. They are in chapters 2 (mathematical methods), 36 (clusters), 73 (heterostructures) and 74 (superconductivity). Only the growth in superconductivity can be considered to be a knowledge epidemic. All four arose due to new instrumentation and/or cheaper materials and are examples of puzzle-generating and enabling science. A second major result was that information epidemics are caused by as well as carried forward by groups of influential works. Third, increased activity in a given field is accompanied by an increase in conference papers. On the other hand, the journal literature of a given field is sufficient to represent the direction of literature, growth accurately. / This work confirms and extends the epidemic model for the growth of literatures by demonstrating that not only does the contagion effect exist in physics but that there is also a catalyst effect present. It provides a statistical description for the growth and decline of fields of research.

No description available.

O presente trabalho propõe-se analisar a forma como os fatores sociais, associados à prática do aleitamento materno, vêm sendo tratados na literatura científica. Num primeiro momento, procura identificar o comportamento do volume da produção científica, seguindo-se à identificação e análise dos fatores sociais arrolados nos estudos sobre a prática do aleitamento materno. O material de estudo compreende os trabalhos indexados na \"Nutrition Abstracts and Reviews\", no período de 1945 a 1985. Concluiu-se que a produção de conhecimento científico sobre o aleitamento materno faz-se presente em todo o desenvolvimento científico sobre nutrição infantil, no período estudado, com importância relativa acentuada em determinados momentos históricos. Destaca-se a produção de trabalhos sobre a prática do aleitamento materno dentre os estudos sobre o aleitamento materno. Identificam-se, como mais freqÜentes, entre os fatores sociais associados, o nível socio-econômico, o nível educacional, a distribuição urbano-rural e o trabalho da mulher. Os fatores sociais, arrolados nos estudos sobre a prática do aleitamento materno, caracterizam-se numa abordagem predominantemente multicausal. / The purpose of this work is to analyse how social factors associated with breast-feeding have dealt with scientifical literature. At first it outlines the behavior of the total scientific production and then it identifies and analyses the social factors connected up with the practice of breast-feeding. The material for this study encloses all the papers indexed in Nutrition Abstracts and Reviews throughout the period comprised between 1945 and 1985. There is concluded that the production of scientific knowledge on breast-feeding has been present throughout the general scientific development of child nutrition in the studied period with relative more deeper importance at certain historical moments. The practive of breast-feeding has been more dealt with studying breast-feeding at large. The most frequently associated social factors that were identified in this work were the socio-economic level, the educational level, the urban-rural distribution and women employment. These social factors connected up with breast-feeding practice have been approached essentialy from a multicausal angle.

O presente trabalho propõe-se analisar a forma como os fatores sociais, associados à prática do aleitamento materno, vêm sendo tratados na literatura científica. Num primeiro momento, procura identificar o comportamento do volume da produção científica, seguindo-se à identificação e análise dos fatores sociais arrolados nos estudos sobre a prática do aleitamento materno. O material de estudo compreende os trabalhos indexados na \"Nutrition Abstracts and Reviews\", no período de 1945 a 1985. Concluiu-se que a produção de conhecimento científico sobre o aleitamento materno faz-se presente em todo o desenvolvimento científico sobre nutrição infantil, no período estudado, com importância relativa acentuada em determinados momentos históricos. Destaca-se a produção de trabalhos sobre a prática do aleitamento materno dentre os estudos sobre o aleitamento materno. Identificam-se, como mais freqÜentes, entre os fatores sociais associados, o nível socio-econômico, o nível educacional, a distribuição urbano-rural e o trabalho da mulher. Os fatores sociais, arrolados nos estudos sobre a prática do aleitamento materno, caracterizam-se numa abordagem predominantemente multicausal. / The purpose of this work is to analyse how social factors associated with breast-feeding have dealt with scientifical literature. At first it outlines the behavior of the total scientific production and then it identifies and analyses the social factors connected up with the practice of breast-feeding. The material for this study encloses all the papers indexed in Nutrition Abstracts and Reviews throughout the period comprised between 1945 and 1985. There is concluded that the production of scientific knowledge on breast-feeding has been present throughout the general scientific development of child nutrition in the studied period with relative more deeper importance at certain historical moments. The practive of breast-feeding has been more dealt with studying breast-feeding at large. The most frequently associated social factors that were identified in this work were the socio-economic level, the educational level, the urban-rural distribution and women employment. These social factors connected up with breast-feeding practice have been approached essentialy from a multicausal angle.

Univ., Diss--Gießen, 2006.

Thesis (Ph. D.)--University of Wisconsin--Madison, 1975. / Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.

No description available.