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1.
Here, we present the results of a genetic analysis of 463 Pottoka ponies corresponding to four generations, using 17 microsatellite markers. Ten years after the beginning of the Pottoka conservation programme, the values for the genetic diversity of the breed are still high and stable, indicating the success of the programme. We found null alleles in Pottoka for the ASB23, HMS3 and HTG10 microsatellites. Together with information obtained from other pony breeds from the Iberian Peninsula, this finding indicates that these microsatellites should not be used for phylogenetic analyses or parentage tests, at least for these breeds. The high heterozygosity exhibited by this breed in comparison to other ponies, together with its genetic proximity to the centroid of the allele frequencies, suggest that Pottoka allele frequencies are close to those initially exhibited by the ancestors of current European ponies. The results obtained in the current work, together with results from previous studies of ponies and horses from the Iberian Peninsula, corroborate the idea of a unique origin of all ponies from the European Atlantic Area. In contrast, our results do not corroborate the idea that these are derived from a domestication event in the Iberian Peninsula, nor that they have incorporated ancient Iberian horse genes into their genetic pool to a larger extent than other horse breeds.  相似文献   
2.

Background, aim, and scope  

The mobility of arsenic in soils and its transfer to other environmental components present significant environmental risks. The management of polluted land is determined by the availability, mobility, and transfer of inorganic pollutants to different ecosystem compartments. In this paper, the fate of arsenic at this mining site has been evaluated to determine future management practises to minimise such risk.  相似文献   
3.
Subsurface-flow constructed wetlands technology (SSFW) has been used successfully for treating sanitary wastewater throughout North America and Europe. However, treatment wetland technologies have not been used extensively in the tropics. To advance tropical studies, a pilot-scale SSFW was constructed on the campus of the University of the Atlantic in Barranquilla, Colombia. The systems performance was monitored from January to July of 2009. The treatment system consisted of a 760-L septic tank followed by three mesocsom-scale subsurface-flow constructed wetlands in parallel arrangement. Clarified wastewater was batch loaded to each unit at a rate of 53 L/m2/day to affect a hydraulic retention time of approximately 3 days. One of the treatment units served as a non-planted control (gravel only), while the other two treatment units were planted with either Eriochloa aristata or Eleocharis mutata. The objective of this study was to evaluate the comparative efficacy of the treatment units (planted vs. unplanted), with respect to their abilities to augment treatment of septic tank effluent (sanitary wastewater). Monitored parameters included plant biomass, oxidation?Creduction potential, chemical oxygen demand (COD), temperature, dissolved oxygen, pH, ammonia?Cnitrogen (NH 4 + ?CN) nitrate?C and nitrite?Cnitrogen (NO3?CN, NO2?CN), phosphates (PO 4 ? ), and coliform bacteria. Total biomass (dry matter) was 2.84 and 0.87 Kg/m2 for E. aristata and E. mutata, respectively. Redox potential in the plant rizospheres averaged ?172 mV (±164.1) in E. aristata, 29 mV (±251.1) in E. mutata, and 32 mV (±210.5) in the unplanted control. COD removal was superior in planted vs. non-planted systems (>75% vs. 47%). Ammonia and total phosphorus removal averaged 69% and 85%, respectively, in planted systems versus 31% and 59% in the unplanted system. Removal of total and fecal coliforms averaged 96%. Results of this pilot study revealed that SSFW technology in the tropics can provide significant removal of organic matter, nutrients, and bacteria from clarified sanitary wastewater.  相似文献   
4.
This study examines the daily and annual changes in amylase and basic and acid protease activities in gilt‐head sea bream, Sparus aurata. During the experiment, the fish were kept in cages for production under natural temperature and photoperiod conditions and fed with a commercial diet. To study the effect of photoperiod and temperature, the experiments were conducted during six different months that were chosen based on temperature and photoperiod. To determine daily changes in enzymes activities, for every 3 h during 24 h period, six fish were randomly selected and sacrificed. The annual results for acid protease activity show a rhythm with 6‐mo period (bimodal rhythm) with acrophases in May and November. The activities of pancreatic enzymes, which include basic protease and amylase, exhibited parallel changes with two peaks of activity in January and October without a rhythmic pattern. The daily changes in enzyme activities are significant only in May, June, and November for basic proteases and May, October, and November for amylase (P < 0.05). The observed variations suggest a varying capacity for digestion depending on the day and the year and could aid in the study of seasonal feeding protocols.  相似文献   
5.
6.
To enhance the specificity and sensitivity of serological detection of swine exposed to Ornithodoros erraticus or O. moubata, we purified the 158, 186, 215 and 260 kDa antigens from the former species and the designated (owing to their MW and charge) 19C, 17A, 20A1 and 20A2 antigens of the latter by HPLC and gel electroelution methods. All the O. erraticus antigens share epitopes and are difficult to purify individually by reverse phase and ion-exchange chromatography due to their molecular similarity. Tested individually by ELISA, all of them give the same optical densities (OD) with anti-O. erraticus sera, and these ODs are always lower with anti-immature than with anti-adult sera. Although immature and adult specimens have the same antigens, immature forms induce more anti-carbohydrate antibodies than adults. This is the reason for the lower ODs of the anti-immature sera against purified antigens, since these latter antigens essentially react with anti-peptide antibodies (hence, increasing the specificity and sensitivity of the serology). The N-terminus of the 260 kDa antigen shows 80-90% similarity with the hemoglobin alpha-chain of many mammals. The antigens of O. moubata are proteins that are very different from one another and are, therefore, readily purified by ion exchange chromatography. The 20A1 antigen appears to be the most immunogenic and is recognized equally by anti-immature and anti-adult sera. This antigen does not give false positive reactions with the negative control sera analyzed and its N-terminus region shares 46.2% homology with the alpha-chain of the C3 component of rabbit complement.  相似文献   
7.
Aqueous crude extracts of a series of plant wastes (agricultural, wild plants, residues from sports activities (grass), ornamental residues (gardens)) from 17 different plant species representative of the typical biodiversity of the Iberian peninsula were investigated as new sources of peroxidases (EC 1.11.1.7). Of these, lentil (Lens culinaris L.) stubble crude extract was seen to provide one of the highest specific peroxidase activities, catalyzing the oxidation of guaiacol in the presence of hydrogen peroxide to tetraguaiacol, and was used for further studies. For the optimum extraction conditions found, the peroxidase activity in this crude extract (110 U mL(-1)) did not vary for at least 15 months when stored at 4 °C (k(inact) = 0.146 year(-1), t(1/2 inact) = 4.75 year), whereas, for comparative purposes, the peroxidase activity (60 U mL(-1)) of horseradish (Armoracia rusticana L.) root crude extract, obtained and stored under the same conditions, showed much faster inactivation kinetics (k(inact) = 2.2 × 10(-3) day(-1), t(1/2 inact) = 315 days). Using guaiacol as an H donor and a universal buffer (see above), all crude extract samples exhibited the highest peroxidase activity in the pH range between 4 and 7. Once semipurified by passing the crude extract through hydrophobic chromatography on phenyl-Sepharose CL-4B, the novel peroxidase (LSP) was characterized as having a purity number (RZ) of 2.5 and three SDS-PAGE electrophoretic bands corresponding to molecular masses of 52, 35, and 18 kDa. The steady-state kinetic study carried out on the H(2)O(2)-mediated oxidation of guaiacol by the catalytic action of this partially purified peroxidase pointed to apparent Michaelian kinetic behavior (K(m)(appH(2)O(2)) = 1.87 mM; V(max)(appH(2)O(2)) = 6.4 mM min(-1); K(m)(app guaicol) = 32 mM; V(max)(app guaicol) = 9.1 mM min(-1)), compatible with the two-substrate ping-pong mechanism generally accepted for peroxidases. Finally, after the effectiveness of the crude extracts of LSP in oxidizing and removing from solution a series of last-generation dyes present in effluents from textile industries (1) had been checked, a steady-state kinetic study of the H(2)O(2)-mediated oxidation and decolorization of Green Domalan BL by the catalytic action of the lentil stubble extract was carried out, with the observation of the same apparent Michaelian kinetic behavior (K(m)(appGD) = 471 μM; V(max)(appGD)= 23 μM min(-1)). Further studies are currently under way to address the application of this LSP crude extract for the clinical and biochemical analysis of biomarkers.  相似文献   
8.
Tropical Animal Health and Production - Genetic structure and genetic diversity levels of indigenous Iranian sheep breeds are not clear, despite the interest this region has in itself as an...  相似文献   
9.
? The objective of this study was to evaluate and compare nitrogen losses during the composting process developed at two facilities. Both are in Catalonia, which is located in northeast Spain. The research evaluated the effects of process, feedstock content, differences in compost maturity and other factors to explain differences in nitrogen levels. Separation methods and leachate problems were also compared.  相似文献   
10.
The agar dilution method was used to determine the antimicrobial activity of 17 antimicrobial agents against 132 strains belonging to the genus Bacteroides and 25 strains from the genus Fusobacterium, all isolated from 120 clinical cases of caprine footrot between October 1987 and November 1988. Josamycin, chloramphenicol and rifampin proved to be the most effective antibiotics in vitro. Significant resistance was found to the other antimicrobial agents studied.  相似文献   
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