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The cattle dual-purpose production systems (SPDP) has been developed in the tropical areas, characterized by low levels of efficiency that require the analysis of the factors that affect it. In the present study, technical efficiency (ET) was analyzed in 271 production units located in Zulia State, Venezuela, using a stochastic frontier production function. The total income was used as output ($), and the surface (ha), animal units (UA), man work unit (UTH), and total costs ($) were used as input. An average technical efficiency value of 66.63% was obtained, with a range of 19.74 to 99.62, which indicates that there is a wide margin for improvement. In the inefficiency model, the variables stocking rate (UA/ha), and liters of milk per hectare (L/ha) were significant, the coefficient presented a positive sign for the stocking rate, which means that as it increases this parameter the exploitations increase their inefficiency, while for the L/ha the opposite happened. Based on these results, the need to determine the effect exerted by grazing management technologies on ET is raised, this would allow promoting management strategies that tend to optimize the use of forage resources, and thus achieve better levels of ET in the SPDP. [ABSTRACT FROM AUTHOR]

Non-aqueous microemulsions of the ternary system AOT (surfactant), isooctane and ethylene glycol may be composed of spherical or cylindrical aggregates at specific proportions. Using this type of microemulsions it is possible to synthesize silver nanoparticles using silver nitrate as source of the metallic ions. Ethylene glycol serves at the same time as solvent for the silver nitrate and reducing agent of silver ions. The silver nanoparticles synthesized in the spherical aggregates are discrete (average particle size of 10 nm) and do not align. On the other hand, the nanoparticles obtained in cylindrical structures (birefringent phases) align forming linear and ordered arrays. The microemulsions were characterized with optical microscopy between crossed polarizers whereas discrete and linear arrays of silver nanoparticles were observed under transmission electron microscopy to determine their shape and size; HRTEM was used to confirm the crystal structure of the silver nanoparticles and EDS was used for their chemical analysis. [ABSTRACT FROM AUTHOR]

Contents One hundred and twenty-six suckled crossbred cows ( Bos taurus × Bos indicus), with body condition score ≥3 (1–5 point scale), were employed in the present study to evaluate the effectiveness of intravaginal progestin-releasing sponges (IVS) for shortening anoestrous interval. Fifty-four cows were assigned to control group. Seventy-two cows were treated with IVS impregnated with 250 mg of medroxy-acetate-progesterone (MAP) as follows: day 0, IVS plus 5 mg of 17β-E and 50 mg of MAP i.m.; day 6, 500 IU of equine chorionic gonadotropin and 25 mg prostaglandin F2α i.m.; day 8, IVS withdrawal and day 9, 1 mg 17β-E i.m. Cows were also grouped according to postpartum days (dpp) at treatment: MAP <70 days (n = 25); control <70 days (n = 22); MAP >70 days (n = 47); control >70 days (n = 32). From IVS removal, cows were detected in oestrus and inseminated. Cows not detected in oestrus were timed artificial insemination 72 h after sponge removal. Treatment effect on oestrous rate (ER), conception rate (CR), pregnancy rate (PR) and treatment to conception intervals (TCI) and calving to conception intervals (CCI) were evaluated. The ER, CR and PR were analysed usingproc logistic, while TCI and CCI withproc glm of SAS. The groups MAP <70 days and MAP >70 days showed higher (p < 0.01) ER than control <70 days and control >70 days (84.0% and 76.6% vs 31.8% and 31.3% respectively). The PR was higher (p < 0.01) in MAP <70 days vs control <70 days (64.0% vs 22.7%) and also higher (p < 0.05) in MAP >70 days vs control <70 days (40.4% vs 18.8%). The TCI and CCI were shorter (p < 0.01) in MAP <70 days vs control <70 days (36.0 and 95.8 days; 95.3 and 158.6 days respectively). In conclusion, only cows treated with IVS before 70 dpp had a CCI shorter than 100 days, consequently this treatment shortened postpartum anoestrous interval in crossbred dual purpose cattle. [ABSTRACT FROM AUTHOR]

The search of new genetic vectors that improve the efficacy of gene delivery into diseased cells has led to the creation of several vector formulations that promote effectiveness in applications. However, DNA affinity to vectors as well as vector/DNA complex stability remains a problem to be solved. Here, we study lipoplexes made of DODAB-DOPC cationic liposomes (CL) and calf thymus DNA (ctDNA) as a preliminary cargo gene model of a novel vector formulation to improve DNA delivery efficacy and affinity. Physicochemical characterization was carried out by Z -potential (ζ), light scattering, ultraviolet, fluorescence spectra, confocal, and electronic microscopy to prove CL and ctDNA complexation and high affinity. Through this approach, ζ and light scattering results indicate an effective CL and ctDNA complexation; CL charge decreases as ctDNA concentration increases. Obtained spectra from UV and fluorescence show high affinity between CL and ctDNA. This can be also verified by confocal microscopy images and electronic microscopy micrographs. All experiments show effective binding between CL and ctDNA, and fluorescence experiments show EtBr displacing as CL concentration increments. CL cytotoxicity assays show high viability when ctDNA is complexed; these results are comparable with those obtained using Lipofectamine 2000. Easy complexation and low cytotoxicity make them a promising formulation for gene delivery. The obtained results from this work motivate us to keep searching for new genetic vector formulations, which could reduce its cytotoxic effect and improve its transfection efficiency, in addition to the low cost of production compared with some commercial products. [ABSTRACT FROM AUTHOR]

Different stallions exhibit a high level of variation in the ability of their sperm to survive cryopreservation. A large fraction of stallions show poor post-thaw sperm motility, and their semen is not suitable for commercial freezing. In this study, we hypothesized that the presence of sperm-bound antisperm antibodies (ASAs) was associated with poor cryosurvival of stallion sperm. Our objective was to assess the level of ASA binding to stallion sperm, and determine if it was associated with good or poor sperm cryosurvival. In Experiment 1, cooled shipped semen from 27 stallions was frozen using three commercial semen extenders. Sperm motility, membrane integrity, acrosome integrity and apoptosis were evaluated before and after freezing for each aliquot. In addition, the percentage of ASA-bound sperm was evaluated post-thaw. In Experiment 2, semen from 22 stallions was frozen immediately after collection a single formulation of semen extender. Sperm motility and ASA binding were evaluated post-thaw. The results of both experiments showed similar findings. The frequency of ASA-positive samples was higher among stallions with poor sperm cryosurvival (Exp. 1 and 2 = 6/11, 54.5%) than for good sperm cryosurvival (Exp. 1 = 0/16, 0%; Exp. 2 = 1/11, 9.1%). The percentage of IgG- and IgA-bound sperm was also higher in stallions with poor sperm cryosurvival in both experiments (P < 0.05). Post-thaw sperm motility, velocity and distance parameters were lower in ASA-positive than ASA-negative stallions (P < 0.005). No effect of the semen extender used was observed. In addition, stallions with ASAs had a higher percentage of apoptotic sperm than stallions without ASAs. The presence of sperm-bound ASAs was associated with poor cryosurvival for stallion spermatozoa. Thus, it may be beneficial to evaluate stallions for binding of ASAs prior to freezing to offer and indicator of the prognosis for cryosurvival. • 54.5% of stallions with poor sperm cryosurvival had high ASA binding • Less than 10% of stallions with good sperm cryosurvival had ASA binding • Sperm-bound ASAs were associated with poor cryosurvival for stallion sperm • Identifying ASAs binding prior to freezing may offer a prognosis for cryosurvival [ABSTRACT FROM AUTHOR]

Aims Hypoglycaemia is a serious medical emergency. The need for emergency medical service care and the costs of hypoglycaemic emergencies are not completely known. Methods This was a retrospective observational study using Public Company for Health Emergencies ( EPES) data for hypoglycaemia in 2012. The EPES provides emergency medical services to the entire population of Andalusia, Spain (8.5 million people). Data on event type, onsite treatments, emergency room visits or hospitalization were collected. Medical costs were estimated using the public rates for healthcare services. Results From a total of 1 137 738 emergency calls that requested medical assistance, 8683 had a primary diagnosis of hypoglycaemia (10.34 per 10 000 person-years). The incidence of severe hypoglycaemic episodes requiring emergency treatment in the estimated population with diabetes was 810 episodes per 10 000 person-years. A total of 7479 episodes (86%) required an emergency team to visit the patient's residence. The majority of cases (64%) were addressed in the residence, although 1784 (21%) cases were transferred to hospital. A total of 5564 events (65%) involved patients aged > 65 years. Overall mortality was 0.32% (28 cases). The total annual cost of attending a hypoglycaemic episode was €6 093 507, leading to an estimated mean direct cost per episode of €702 ± 565. Episodes that required hospital treatment accounted for 49% of the total costs. Conclusions Hypoglycaemia is a common medical emergency that is associated with high emergency medical service utilization, resulting in a significant economic impact on the health system. [ABSTRACT FROM AUTHOR]

Polycrystalline CsTaWO6 is prepared by calcination of stoichiometric amounts of Cs2CO3, Ta2O5, and WO3 in air (1. [ABSTRACT FROM AUTHOR]

Polycrystalline CsTaWO6 is prepared by calcination of stoichiometric amounts of Cs2CO3, Ta2O5, and WO3 in air (1. [ABSTRACT FROM AUTHOR]