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We have already shown that RSVP14 and RSVP20, two ram seminal plasma (SP) proteins postulated to be involved in sperm capacitation and gamete interaction can protect spermatozoa against cold-shock. In this study, we use two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) for the analysis of SP proteins of Rasa Aragonesa rams, using enhanced protein solubilization in the presence of tributyl phosphine (TBP) and a polyacrylamide linear gradient gel with a narrow pH range (4-7). The image analysis of the 2D map detected 195 protein spots, with isoelectric points (pIs) ranging from 4.5 to 6.6, and molecular weight (M(r)) from 11.7 to 90.4. Staining of 2D gels with Pro-Q Emerald 300 Glycoprotein Stain revealed that most significant proteins in ram SP are glycosylated. The removing of protein N-linked oligosaccharides improved the gel resolution. 2D-PAGE analysis of the whole fraction 6 (F6) separated from ram SP by exclusion chromatography showed six main protein spots, four (a, b, c, d) in the 14 kDa and two (e, f) in the 20 kDa region. Western-blot analyses indicated that the anti-P14 antibody recognized four spots on the SP map, 4, 5, 6 and 7, that matched with spots a, b, c, d of F6 map. The anti-P20 antibody recognized spots 13 and 14 of SP map that corresponded to spots e, f of F6 map. The deduced sequences by de novo sequencing evidenced that protein spots 7 and 13 have significant similarities to BSP family, while protein spots 4 and 14 did not appear to be homologous with any reported protein in the current mammalian Proteinbank databases.  相似文献   
104.
Activation of in vitro‐matured (IVM) oocytes is essential for successful embryo production following nuclear transfer (NT) or intracytoplasmic sperm injection (ICSI). This study was designed to compare the rates of blastocyst production and embryo quality (as measured by numbers of viable cells) following parthenogenetic activation with electrical pulse or the use of two different calcium ionophores, A23187 (CA) or ionomycin (IO), with or without the addition of bovine serum albumin (BSA). IVM oocytes with a first polar body were randomly allocated to five treatment groups: CA (5 μm CA, 5 min; n = 88), CA + BSA (5 μm CA, 5 min; BSA, 5 min; n = 90), IO (5 μm IO, 5 min; n = 91), IO + BSA (5 μm IO, 5 min; BSA, 5 min; n = 86) and EL (two pulses of 1.5 kV/cm, 20 μs; n = 120). Blastocyst rates were higher (p < 0.05) for CA (54.4%), IO (51.4%) and EL (54.5%) than for IO + BSA (18.3%). Treatment CA + BSA (39.8%) did not differ from the others. There was no difference (p > 0.05) among treatments in total number of cells. However, the percentage of viable cells was reduced in CA (49.9%), CA + BSA (45.8%), IO (64.9%), IO + BSA (50.9%) compared with EL (82.7%). In summary, the addition of BSA to the IO treatment had an adverse effect on blastocyst production rates. Although there was no difference between electrical stimulation and chemical activation on blastocyst production rates, electrical activation resulted in blastocysts with a higher percentage of viable cells.  相似文献   
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Buffalo milk represents an indispensable source of nourishment in many parts of the world and it is the second most consumed milk worldwide. Buffalo milk is actually used for the production of many dairy products such as pasteurized or concentrated milk, butter, yogurt, ice‐cream, dehydrated milk products and cheeses. Due to its high nutritional value and the presence of natural bioactive substances, buffalo milk can also provide health benefits to consumers. In Italy, buffalo milk is used mainly for cheese making, mozzarella PDO (Protected Designation of Origin), which is a highly valued dairy product. This 3‐year study, carried out between 2011 and 2013, was aimed at evaluating the quality of bulk Italian Mediterranean buffalo milk by monitoring physico‐chemical parameters, somatic cell and total bacterial counts. A total of 51 samples of bulk milk were collected from one herd throughout the monitored period. Analysis of variance, carried out to test month, season and year main effects, highlighted remarkable seasonal effects for fat, protein and lactose content, as well as for predicted mozzarella cheese yield, and somatic cell counts. The calculation of simple correlations allowed the identification of positive correlations between estimated cheese yield and fat and protein content.  相似文献   
107.
The wood pastures or hardwood rangelands of the southwestern Iberian Peninsula are complex social-ecological systems created from the long-term interaction of society and the landscape. Dehesa, oak woodlands managed for grazing, cropping, and other forms of production, is the most common rangeland system and one of the most distinctive landscapes. Traditionally characterized by multifunctional low-intensity management that enhances a wide range of ecosystem services, current management has shifted from the traditional toward more intensified models. This paper assesses the coproduction of ecosystem services on dehesa properties by exploring the relationship between biophysical and sociocultural factors and dehesa management practices. Based on 42 surveys we analyze 16 quantitative indicators using multivariate techniques. The results indicate that there are four main dehesa types as defined by their characteristics and management: large heterogeneous operations with diverse products; small and homogeneous operations focused on a reduced number of products; medium-large properties focused on crop production; and midsized properties with easy public access. Management is the result of the dynamics of interacting biophysical and sociocultural factors that influence manager priorities and investments. Management decisions group around the degree of multifunctionality of the operation, the relative importance of crop production, the degree of grazing pressure in the system, and how restrictive public access policy is. We find that in the study area, interactions between all the previously mentioned elements covary consistently, generating bundles of ecosystem services associated with each of three management models based on the intensity of management.  相似文献   
108.
 The structure and seasonal changes of earthworm communities were evaluated in a natural savanna and in a improved grass-legume pasture in a Colombian oxisol over a period of 18 months. One plot of 90×90 m was isolated in each of the systems and each month five samples of 1 m2×0.5 m and ten of 20×20×20 cm were randomly selected from a stratified block design. Species richness was similar in the two evaluated plots (seven species), whereas diversity measured by the index, H (Shannon and Weaver 1949) was clearly different, i.e. H=2.89 in natural savanna and H=1.29 in pasture. This is explained by differences in earthworm community structure. The average annual density in the savanna was 49.8, ranging from 10.8 to 135.8 individuals (ind) m–2, and biomass was 3.3 g m–2 (hand-sorting method), ranging from 0.9 to 11.5 g m–2. In the man-made pasture, density was 80.1 ind m–2 on average, ranging from 24 to 215.8 ind m–2 and biomass was more than tenfold higher, ranging from 29.2 to 110.4 g m–2. This was especially due to the presence of a large glossoscolecid anecic species, Martiodrilus carimaguensis Jiménez and Moreno, which has been greatly favoured by conversion of savanna to pasture. Endogeic species were dominant in the natural savanna whereas the anecic species accounted for 88% of total earthworm biomass in the pasture. Total earthworm density and biomass were significantly different in the two systems studied (t-test). The results indicate a clearly positive response of earthworm communities to improved pastures, a type of land use that is being increasingly adopted in moist neotropical savannas. Received: 20 October 1997  相似文献   
109.
Direct water electrolysis was achieved with a novel, integrated, monolithic photoelectrochemical-photovoltaic design. This photoelectrochemical cell, which is voltage biased with an integrated photovoltaic device, splits water directly upon illumination; light is the only energy input. The hydrogen production efficiency of this system, based on the short-circuit current and the lower heating value of hydrogen, is 12.4 percent.  相似文献   
110.
Four Missouri stalagmites yield consistent overlapping records of oxygen and carbon isotopic changes and provide a climate and vegetation history with submillennial resolution from 75 to 25 thousand years ago (ka). The thorium-230-dated records reveal that between 75 and 55 ka, the midcontinental climate oscillated on millennial time scales between cold and warm, and vegetation alternated among forest, savanna, and prairie. Temperatures were highest and prairie vegetation peaked between 59 and 55 ka. Climate cooled and forest replaced grassland at 55 ka, when global ice sheets began to build during the early part of Marine Oxygen Isotope Stage 3.  相似文献   
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