1,721,064 research outputs found
‘Vetri e ancoraggi’
No full texttutti i sistemi di ancoraggio e fissaggio del vetro nelle soluzioni di involucr
Genetic improvement strategies in buffalo.
No full textBreeding and official selection activity in any country depends on the economic importance of the considered livestock, therefore of the products that can be obtained from it. The first step in the breeding and selection activity with regard to any dairy livestock is the milk recording of the productivity of each yielding animal. The results, when appropriately merged with the genealogy data, allow a definition of the milk genetic merit of each animal, in particular of the bull, for which we have no other milk record except the production of his progeny. The importance of animal recording for the activity of selection is well recognized all over the world and is demonstrated by the fact that in most countries such activity is at least partially financed by governments, which consider it an important means for the improvement of animal production. An international non governmental organization, the International Committee for Animal Recording (ICAR) has been active for over thirty years in the field of promotion and standardization of animal recording. The highest proportion of milk recorded buffaloes, in fact, is found in Italy (27.8%), in Iran is 4.5 %, while in other countries the recorded buffaloes are about 1% of total dairy females (Turkey, Egypt) or less. We have high percents of recorded buffaloes in Bulgaria, Syria and Greece, where the buffalo population is disappearing. The productivity in other countries is lower than in Italy, considering that only in Italy there was a very long work of recording, selection and genetic improvement, health, feeding and livestock system rising. Also milk composition was improved in Italy in few years, with mean protein percentage from 4.4 to 4.8 and fat percentage from 7.3 to 8.1 without any selection of this character. Moreover the possibilities of genetic improvement for milk quantity and quality will be higher, if the selection pressing will be increased reducing the number of bred females. So, just now there are in Italy many females producing more than 5,000 kg milk for lactation (270 days). Therefore the selection will be directed for the improvement of the yield of mozzarella cheese, not simply for milk production, because the farm income actually is resulting first from mozzarella cheese, alter from the selling of pregnant heifers, at the last from beef (Borghese, 2004). A consistent number of recorded buffaloes is obviously found in countries with the highest presence of buffaloes (India, Pakistan and Egypt) which signifies that these countries have also taken steps towards implementing an organized milk improvement activity, on a solid scientific and technical basis
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
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe 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
Prediction of retention times in linear gradient temperature and pressure programmed analysis on capillary columns
No full textThe simultaneous temperature and inlet pressure programming (TPP) in gas chromatographic analysis decreases the retention time and the maximum value of temperature required for the elution of high boiling substances. Therefore, compounds sensitive to thermal degradation can be better analysed and column ageing is reduced. However, the empirical choice of proper analysis conditions requires many preliminary runs; this paper describes a procedure for the theoretical prediction of retention times in TPP using few preliminary runs carried out in isobaric and isothermal conditions. The used program permits the prediction of the retention times of the compounds analysed with any different TPP run carried out within the temperature and pressure ranges investigated with the preliminary runs. The influence of various analytical parameters on the accuracy of the prediction values was investigated. The proposed model also predicts the relative position in the chromatogram of closely eluting peaks and the possible coincidence of retention times or inversion of the elution order with changing temperature. It is also possible to foresee the analytical conditions, which offer a baseline separation of all of the peaks of the sample
Oocyte retrieval in superstimulated buffalo heifers.
No full textEmbryo production following oocytes in vitro fertilization is related on number of oocytes collected by Ovum pick-up. The objective of this study was to compare stimulated peripuberal buffaloes and to assess ovarian response and oocyte recovery. On day 0, 12 heifers undergone clinical examination of genital tract by ultrasound and a progesterone releasing intravaginal device was inserted into the animals. On day 3 buffaloes were divided into two treatment groups , according to their age, body weight and follicular population on day 0 and 3. On day 7 all buffaloes undergone ultrasound examination and number and size of the follicles was recorded. Heifers in Group A (n=6) received a 4-day decreasing dosage of an equal mixture of 500 I.U. of Follicle Simulating Hormone and 500 I.U. of Luteinizing hormone; Group B (n=6) received a single i.m. injection of Pregnant Mare Serum Gonadotrophin and a 2-day decreasing dosage of an equal mixture of 175 I.U. of FSH and 175 I.U. of LH, starting on day 5. Group B resulted in a significantly higher (P<0.05) number of large-very large follicles compared to group A (13.2 vs 8.3). Although no significant differences, in group A and B, were found on the number of observed follicles (14.2 vs 18.2), aspirated follicles (11.5 vs 14.0), recovered oocytes (6.33 vs 6.5) and percentage of recovered oocytes/aspirated follicles (60,0 vs 44.8), all the parameters tended to be higher in group A. The percentage of viable oocytes (3.2 vs 3.2) was similar. Protocol B stimulated the recruitment and the growth of a higher number of small follicles. It is possible to hypothise that the higher size of the follicles in group B, caused the lost of follicular fluid affecting oocyte recovery
- …
