Concentration of Bacillus spores by using silica magnetic particles

Silica particles are mainly used for the concentration of nucleic acid for diagnostic purposes. This is usually done under acidic or chaotropic conditions that will demolish most of the living organisms and prevent the application of other diagnostic tests. Here we describe the development of a method for the capturing and concentration of Bacillus spores using silica magnetic particles to enable fast and sensitive detection. We have shown that capturing various Bacilli spores via silica magnetic particles is limited, with large differences between spore batches (42 +/- 25%). The hydrophobic exosporium layer of spore limits the capture by the hydrophilic silica beads. Partial removal of Bacillus exosporium increases capture efficiency. To increase capturing efficiency without harming the spores' viability, a cationic lipid, didecyldimethylammonium bromide (DDAB), was used as a coat for the negatively charged silica particles. DDAB treatment increased capture efficiency from 42% to more than 90%. Using this method, we were able to capture as few as 100 Bacillus anthracis spores/mL with 90% efficacy. Release of captured spores was achieved by the addition of albumin. The capture and release processes were verified by plating and by flow cytometry using light scatter analysis. The method is simple, efficient, easy to operate, and fast.     

Relation of title length of journal articles to number of authors

The great importance of titles being highly informative is almost unanimously accepted in literature, assuming that the more informative titles are, the more effectively they serve their functions. The most common measure of title informativeness has been the number of substantive words included in it, and one of the factors which might be associated with it is the number of authors. The present study attempted to test, in a large group of journals fromdifferent areas, and over six decades, the hypothesis that a paper signed by a larger number of authors will have more substantive words in its title. Large samples of original research papers were drawn from each decade year of fourteen leading journals. For each paper, the number of substantive words in the title was correlated with the number of authors. Findings indicate a difference between the scientific journals on the one hand, and the social sciences and humanities journals on the other. A moderate positive correlation was found in most scientific journals (excluding mathematics) for many periods. In the social sciences journals, and to a greater extent, in the humanities journals, a significant positive correlation was limited to only a few periods, while the rest showed a very low correlation, or even a negative correlation. The different findings for the sciences may be somehow associated with their higher rate of multiple authorship.Paper presented at the Fourth International Conference on Bibliometrics, Informetrics and Scientometrics in Berlin (Germany), September 11–15, 1993.     

The ‘language preference’ in sociology: Measures of ‘language self-citation’, ‘relative own-language preference indicator’, and ‘mutual use of languages’

Although between one-third to one-half of world social sciences research literature is published in languages other than English, studies show very scant use of it by American and English scholars. Almost all studies, however, were conducted from the Anglo-Saxon perspective, limiting the scope of the study to English-published sources or English-speaking scientists and research workers. The present study aimed at assessing the scope of the language preference in a social sciences field, not only among American and British scholars, but among German and French ones as well, using the technique of citation analysis. Samples including mostly 50–60 original research articles were drawn from the 1985–1994 volumes of nine leading sociology journals published in the US, UK, Germany and France and the references appended to each were scrutinized in order to determine the frequency distribution of the languages cited in each periodical. Findings clearly showed a strong preference of writers to cite material in their own language. However, the extent of this bias differed from journal to journal. The American and British writers rank first, with close to 99% of their references being in English. German scholars rank next, preferring German sources in 75% of the cases, and French scholars quote French sources in only 66% of their references. In order to calculate the new refined measure of ‘relative own-language preference’ (ROLP) indicator, the proportions of ‘language self-citation’ were related to the estimated proportions of these languages in the existing body of sociology research. This measure reveals that German sociologists have the strongest bias towards their mother-tongue, their ratio of references in German exceeding almost 12 to 28 times the expected figure according to the German language share in sociology research. Next come French sociologists (8 to 14 times) while American and British ones display the lowest own-language bias, only slightly higher than expected. Further analysis of the foreign languages preference of each group, according to a ‘mutual-use’ matrix, shows a relative low use of German and French sources by British-American sociologists.     

Number of references in biochemistry and other fields; A case study of the Journal of Biological Chemistry throughout 1910–1985

Large samples of papers published in theJournal of Biological Chemistry in all decades and in some mid-decades werechecked in order to study the referencing pattern, throughout the period 1910–1985, in an internationally leading journal, with especially high citation impact. All measures show that there has been a significant growth in the number of references per paper, during most of the period, but mainly from the 1950's on, refuting Meadows' upper limit. A detailed comparison to a wide range of fields shows theJBC rates to be among the highest. Eight factors affecting the number of references are discussed, and some projections for the future are made.     

Variation in informativity of titles of research papers in selected humanities journals: A comparative study

Titles constitute the most concise statement of a document's content, and are heavily used by information retrieval systems. Consequently, the great importance of titles being highly informative is indisputable. The most common measure of title ‘informativity’ has been the number of ‘substantive’ words it includes. Previous studies found significant differences between journals of different subject fields, in the sciences and the social sciences, regarding the number of substantive words in article titles. However, unlike the sciences and the social sciences, very little research has been done onhumanities journals. Examining title informativity in a group of eighteen leading English-language journals, covering various humanities disciplines, from 1940 to 1990, the present study searched for possible differences between the humanities journal and the scientific and social sciences ones, concerning patterns of title informativity. Generally, considerable differences were found in the number of substantive words in article titles between the various humanities journals checked. On the other hand, a comparison of thegroup-average means and medians of the humanities journals to group figures of journals from the sciences and the social sciences indicates significant differences for almost all decade years studied. However, titles of papers in humanities journals did follow the general trend of increase in informativity, although in a slower pace. Possible explanations of these differences are discussed and areas for further study are suggested. Paper presented at the Round Table On Editors Of Library Journals (RTELJ) at the 61st IFLA General Conference, 20–26 August 1995, Istanbul.     

Own-language preference: A new measure of “relative language self-citation”

A significant portion of scientometrics research involves studies of relative citation rates to groups of citable items. This paper examines the relative citation rates to own-language as compared to foreign language materials. A simple probabilistic model of citation behavior is defined, which suggests a natural measure of relative citation rate. Unlike earlier indicators, our measure is independent of the size of the base population.     

Relation of the title length of a journal article to the length of the article

The great importance of titles being highly informative is almost unanimously accepted in literature, assuming that the more informative titles are, the more effectively they serve their functions. The most common measure of title “informativeness” has been the number of “significant” (i.e., non-trivial) words included in it, and one of the factors which might be associated with it is the length of the paper, measured by its number of pages. The present study attempted to test, in a large group of journals from different areas and over six decades, the hypothesis that a paper with more pages will have more “significant” words in its title. Large samples of original research papers were drawn from each decade year of twenty-four leading journals selected from the sciences, the social sciences and the humanities. For each paper, the number of “significant” words in the title was correlated with the number of pages. Findings indicate a difference between the scientific journals on the one hand, and the social sciences and humanities journals on the other. A moderate positive correlation was found in most scientific journals for many periods. In the social sciences journals, and to a greater extent, in the humanities journals, a significant positive correlation was limited to only a few periods, while the rest showed a very low correlation, or even a negative one. The different findings for the sciences are perhaps attributable to their unique inherent features. This revised version was published online in August 2006 with corrections to the Cover Date.     

The “own-language preference”: Measures of relative language self-citation

It has already been pointed out that the foreign language barrier is probably the greatest impediment to the free flow and transfer of information. This barrier is even growing as scientists of more and more countries publish in their own languages. Almost all studies addressing the language barrier problem were conducted from an Anglo-Saxon perspective, limiting their scope to English-language sources or English speakers. Little research has been devoted to studying and measuring language preference among non-English-speaking scholars. This article reviews measures proposed in former studies such as the “relative own-language preference” indicator, and the “straight odds ratio”, pointing out their advantages and drawbacks. Two new refined measures (in both “raw” and normalised versions) are offered, claiming to be free of these drawbacks, and thus enabling a better and more reliable comparison between journals of different languages. Practical use of the proposed measures is illustrated by applying them to findings of a former language-citation study done on nine sociology journals.