1,721,005 research outputs found
Agriculture and livestock in the National Park of Cilento e Vallo di Diano district between 1970 and 1990.
No full textThe changes of bovine consistence have been investigated in three census period (1970; 1982 and 1990) in the Salerno district of south Italy. Comparing bovine breeding activities in the National Park of Cilento and Vallo di Diano (NP-CVD) at different altimetric (mountain, hill and plain) zones, resulted that there are more bovine farms, bovine and cow numbers in mountain territory respect to the hill and plain.In the latter the farms are more represented in the free lands. After a decrease recorded between 1970 and 1982 census, bovine and cow numbers increased and reached a consistent numbers in the last census of 1990 in mountain and plain
Agriculture and livestock in the National Park of Cilento e Vallo di Diano district between 1970 and 1990.
No full textThe changes of bovine consistence have been investigated in three census period (1970; 1982 and 1990) in the Salerno district of south Italy. Comparing bovine breeding activities in the National Park of Cilento and Vallo di Diano (NP-CVD) at different altimetric (mountain, hill and plain) zones, resulted that there are more bovine farms, bovine and cow numbers in mountain territory respect to the hill and plain.In the latter the farms are more represented in the free lands. After a decrease recorded between 1970 and 1982 census, bovine and cow numbers increased and reached a consistent numbers in the last census of 1990 in mountain and plain
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
Effect of GnRH administration on progesterone blood levels in buffalo.
No full textGnRH administration in buffalo species caused an increase of progesterone 96 hours after treatment. This aspect may result useful in order to increase progesterone blood levels and reduce the phenomenon of embryo mortality in buffalo. The aim of this study was to verify the pituitary response to a GnRH administration on day 6 post-insemination in buffalo. The trial was carried out in January on 21 pluriparous Italian Mediterranean Buffaloes (DIM=118±50 days). The animals were synchronized by using the Ovsynch-TAI Program and inseminated twice, 16 and 40 hours after the last administration of GnRH, with frozen semen. On day 6 post-insemination, buffaloes were treated with 12 μg of Buserelin acetate. Blood samples were collected just before GnRH administration (time 0 – T0) and 30 minutes (time 1 – T1), 3 hours (time 3 – T3) and 24 hours (time 24 – T24) after administration, in order to determine LH, FSH and E2 levels by using a double antibody radioimmuno assay (RIA) on plasma. Pregnancy diagnosis was performed 40 days post-insemination by ultrasound. The differences between the mean levels of LH, FSH and E2 after Buserelin acetate administration were analysed by t Student test. The administration of 12 mcg of Buserelin acetate significantly (P<0.01) increased LH and FSH blood levels after 30 minutes (T1) and after 3 hours (T3), lowering to the initial values after 24 hours (T24). Similarly to these hormones, the estradiol significantly (P<0.01) increased after 30 minutes (T1), decreasing to the basal levels after 3 hours (T3). The use of GnRH or some analogues determines in buffalo as in cattle a pituitary response after only 30 minutes from the administration. Similar results have been recorded from other authors, who reported a P4 increase after 96 hours from the treatment. This increase was more evident after 10 days. Therefore the use of GnRH or its analogous represents a good tool in order to increase P4 levels in buffalo species. This aspect may result useful in order to improve the uterine environment and favourite embryo implantation
Effect of Osteopontin on Bovine Sperm Capacitation.
No full textWe evaluated the effects of osteopontin (OPN) on bovine sperm capacitation in vitro. Frozen-thawed sperm from a bull previously tested for IVF were separated by Percoll and incubated in TALP medium without capacitating agents (control, N = 494) and in the presence of 10 μg (N = 452) and 20 μg of OPN (N = 482) for 2 h. Following incubation, sperm were exposed for 15 min to 60 ug mL-1 of lysophosphatidylcholine, an agent known to induce the acrosome reaction only in capacitated spermatozoa. Trypan blue was first used to differentiate live from dead spermatozoa; dried smears were then fixed in formalin and stained with Giemsa for acrosome evaluation by light microscopy. The proportion of live, acrosome-reacted spermatozoa, was used to assess the efficiency of capacitation under different incubation conditions. Differences among groups were analyzed by Chi Square. No difference in the percentage of live cells was found between the control and 10 μg OPN (44.8, 48.0 % respectively), whereas sperm viability was significantly (P<0.01) decreased by 20 μg OPN (33 %). Treatment of sperm with both 10 μg and 20 μg of OPN significantly increased the capacitation rate, as indicated by the higher percentages of acrosome-reacted sperm compared to the control (31.3, 33.3 vs 14.4 % respectively; P<0.01). Our results demonstrate that OPN facilitates bovine sperm capacitation in vitro and suggest investigating the effect of this factor on in vitro fertilization. (USDA grant 2004-34437-15106
Effect of gametes co-incubation time on in vitro fertilization and embryo development in buffalo species (Bubalus bubalis).
No full textThe aim of this work was to evaluate whether shortening the sperm-oocyte co-incubation time improves embryo development in buffalo species.
Cumulus-oocytes complexes (n=190), recovered from slaughtered animals, were matured in vitro in TCM 199 + 10 % FCS, 0.5 g/mL FSH, 5 g/mL LH, 1 g/mL 17- estradiol and 50 M cysteamine, at 38.5°C under 5 % CO2 in humidified air for 22 hours. The mature oocytes were fertilized in vitro at 38.5°C under 5% CO2 in humidified air in Tyrode’s modified medium (TALP), in the presence of 0.01 mM heparin, 0.2 mM penicillamine and 0.1 mM hypotaurine. Frozen-thawed sperm from a tested bull was treated by the swim-up procedure and used at a final concentration of 206/ml. Presumptive zygotes were removed from TALP medium respectively at 8 h (N=94) and 20 h (N=96) post-fertilization, and cultured in SOF medium, supplemented with essential and non-essential amino acids and BSA, in a gas atmosphere of 5% CO2, 7% O2, and 88% N2 up to the blastocyst stage. On day 5 (day 0=IVF) cleavage rate was assessed and embryos were transferred into fresh SOF medium for further 2 days of culture. Embryo development, in terms of tight morulae (TM) and blastocysts (Bl), was evaluated on day 7. Data expressed in percentages were analyzed by Chi square. Although cleavage rate was significantly lower at 8 h vs 20 h of co-incubation of the gametes (48.9 % vs 63.5 % respectively; P<0.05), both the percentages of TM+Bl and of Bl, evaluated on the total inseminated oocytes, were not different (TM+Bl: 22.3 % vs 18.7 %; Bl: 18.1 % vs 12.5 %). In fact, a significantly (P<0.05) higher proportion of cleaved eggs developed into TM+Bl and Bl in the 8 h-group vs the 20 h-group (TM+Bl: 45.6 % vs 29.5 %; Bl: 37.0 % vs 19.7 %). Our results suggest that prolonging the sperm-oocyte co-incubation time results in a higher penetration and cleavage rate in buffalo without affecting post-fertilization embryo development. To our knowledge no information are available on the chronology of sperm penetration of buffalo oocytes in vitro; it is possible that an interval of time longer than 8 h is required for buffalo sperm to penetrate the oocytes in vitro. On the other hand the improved development of the cleaved oocytes in the 8 h group may indicate that extending the co-incubation time is detrimental to embryo development. This aspect may be accounted for by either a higher occurrence of polyspermia and abnormal fertilization or by the unsuitability of the fertilization medium for the zygotes, once penetration has been achieved. In conclusion shortening the co-incubation time of the gametes may improve development of cleaved oocytes in buffalo even if it results in a decrease of cleavage rate. This recent finding suggests that it will be worth to investigate the effects of intermediate co-incubation times and the interaction with other factors on buffalo in vitro embryo development
In vitro culture of buffalo (Bubalus bubalis) embryos in the presence or absence of glucose.
No full textThe aim of this study was to evaluate whether the presence or absence of glucose during in vitro embryo culture, would affect embryo development in buffalo. Cumulus-oocytes complexes (n=1114, over 8 replicates), recovered from slaughtered animals, were matured and fertilized in vitro according to our standard procedures (1). On day 1 (Day 0 = fertilization), zygotes were cultured in: group A) Glucose-containing SOF throughout culture; group B) Glucose-containing SOF for early culture (Day 1 to Day 4) and glucose-free SOF for late culture (Day 4 to Day 7); group C) glucose-free SOF throughout culture and group D) glucose-free SOF for early culture and glucose-containing SOF for subsequent culture. In vitro culture was carried out at 38.5°C under 5% CO2, 7% O2, and 88% N2. Cleavage rate was evaluated on Day 4 and blastocyst yield, in relation to cleaved embryos, was recorded on Day 7. Differences among groups in blastocyst rate were analyzed by Chi Square test. The presence or absence of glucose did not affect cleavage rate (54.2 % vs 55.7 % respectively). By contrast, significantly higher blastocyst yields were found in Group A and B compared to Groups C and D (32.7 %, 30.7 %, 2.4 % and 9.6 % respectively; P<0.01). It is concluded that in buffalo, unlike sheep and cattle, glucose is more critical for early embryo development than for post-compaction development, as indicated by the poor embryo yield obtained in both groups lacking glucose during early culture. 1) Gasparrini B., 2002, Theriogenology, 57 (1), 237-256
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