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141.
142.
Alma L. Valenzuela Ruben Vasquez-Medrano Jorge G. Ibanez Bernardo A. Frontana-Uribe Dorian Prato-Garcia 《Water, air, and soil pollution》2017,228(2):67
The electrochemical elimination of the herbicide diquat dibromide (DQ) in an undivided electrochemical cell (Condiacell®-type cell) and an H-type cell (a divided electrochemical cell) using boron-doped diamond (BDD) electrodes is reported for the first time. The degradation of essentially 100% of the DQ present was achieved in the undivided electrochemical cell and ca. 92% in the H-type cell. Nearly 80% of the total organic carbon (TOC) and of the chemical oxygen demand (COD) were removed after 5 h of treatment at different current densities (i.e., 0.5, 1.0, and 1.5 mA/cm2 for the undivided cell, and 2.5, 5.0, and 7.5 mA/cm2 for the H-type cell) with a maximum specific energy consumption of approximately 150 kWh kg?1 of COD degraded in the undivided cell, and 300 kWh kg?1 of COD in the H-type cell. Energy consumption of about 0.30 kWh g?1 of TOC occurred in the undivided electrochemical cell and 2.0 in the H-type cell. In spite of obtaining similar percentages of DQ degradation and of COD and TOC removal, a smaller energy usage was required in the undivided cell since smaller current densities were employed. Best results were obtained with the undivided cell, since it required a smaller current density to obtain virtually the same percentage of DQ degradation and removal of COD and TOC. The results obtained herein show that the use of electrochemical advanced oxidation processes may be a good alternative for DQ degradation in polluted water. 相似文献
143.
Are silvopastoral systems compatible with forest regeneration? An integrative approach in southern Patagonia 总被引:1,自引:1,他引:0
Rosina Soler Guillermo Martínez Pastur Pablo Peri María Vanessa Lencinas Fernando Pulido 《Agroforestry Systems》2013,87(6):1213-1227
We used an integrated approach to analyze the influence of silvopastoral management on the biotic and abiotic factors influencing on the natural recruitment of native forests in Tierra del Fuego (Argentina). The probabilities of transition from flowers to seeds to seedlings were estimated in forests with silvopastoral management (i.e., stands that had been both grazed and thinned), secondary growth stands, and unmanaged old-growth areas. Pre-dispersal losses were caused by microclimate and insect predation acting on flowers and immature fruits. Post-dispersal losses resulted from the impact of reduced litterfall and microclimate. But the most critical stage of the overall cycle was seedling establishment. Silvopastoral practices and stand age modified the main drivers of regeneration. While flowering was unaffected by management, fruiting and seed production were more successful in unmanaged forests. Seedling establishment and survival were favored by canopy cover reduction in silvopastoral stands. The increase of solar radiation and soil moisture in managed forests positively influenced the seedling establishment and survival, while in second-growth forests it was limited by suitable micro-site availability. Thinning practices aimed at increasing the understory heterogeneity in mature forests and restoring canopy complexity of second-growth stands could be suitable for sustainable management of these temperate forests. 相似文献
144.
Miguel Angel Scarpa Alejandro Nazareno Etchecopaz Ruben Antonio Abrantes Javier Alejandro Mas Camilo Romero Núñez Laura Miranda Contreras 《Veterinary dermatology》2021,32(3):297-e81
Trichophyton benhamiae was diagnosed in a 9-year-old female dog by histopathological evaluation, fungal culture and confirmation by sequencing of the internal transcribed spacer region of ribosomal DNA. Successful therapy was achieved with itraconazole, bathing with miconazole and chlorhexidine shampoo, and topical application of sodium hypochlorite as a rinse. 相似文献
145.
Short communication: Estrus synchronization using progestogens or cloprostenol in tropical hair sheep 总被引:1,自引:1,他引:0
Alejandro Alavez Ramírez Jaime Arroyo Ledezma Ruben Montes Pérez Roberto Zamora Bustillos Luis Fernando Navarrete Sierra Hector Magaña Sevilla 《Tropical animal health and production》2014,46(8):1515-1518
The objective of the experiment was to compare the use of a PGF2α analogue (Cloprostenol) IM, with an intravaginal progestagen sponge, flurogestone acetate (FGA), and equine chorionic gonadotropin (eCG) IM application protocol. A total of 30 cyclical hair ewes (54.07?±?0.5 kg live weight, body condition score 3.5?±?0.5, and age 3?±?1 years) were used. For the control group ewes (n?=?15), intravaginal sponges (IS) impregnated with 20 mg of FGA were inserted for 12 days with 500 IU of eCG IM at sponges withdrawal. For the PG group ewes (Treatment group n?=?15), two injections of Cloprostenol (75 mcg) were given 12 days apart. The presence of estrus was detected using two rams with 8 h interval beginning at the end of the treatment. Progesterone concentrations in blood were measured by solid phase radioimmunoassay. A student’s t test was performed to analyze the duration of estrus and the interval between the ends of the treatment and the onset of estrus (ET-OE) presentation. Progesterone levels were compared with two-way ANOVA, with treatment, and day of menstrual cycle as fixed factors. Treatment costs ratio was calculated by dividing the total costs of FGA IS application between total costs of Cloprostenol application. Significant differences (P?0.05) were found in the (ET-OE) interval and estrus duration. For the control group, estrus was presented at 30?+?8.2 h; in treatment group, at 44 h after the last application, duration of estrus was 54.9?+?8.34 h, and 41?+?1.83 h for the control and treatment group, pregnancy rates were 53.3 and 60.0 %, respectively. Significant differences (P?0.001) were found from days 9 to 13 on Progesterone levels in both treatments. Treatment costs of Cloprostenol protocol were 2.63 cheaper than FGA including disposable material, biological products, and labor. It was concluded that Cloprostenol could be an effective tool in estrus synchronization in hair sheep in tropical areas. 相似文献
146.
J. F. Rivera‐Benitez K. Rosas‐Estrada E. Pulido‐Camarillo A. de la Peña‐Moctezuma H. Castillo‐Juárez H. Ramírez‐Mendoza 《Zoonoses and public health》2014,61(2):131-137
We conducted an immunological assay of blood samples taken from 85 swine‐specialist veterinarians attending the Congress of the Mexican Association of Swine Specialist Veterinarians in Mexico in 2011. Serum samples were assayed for Porcine rubulavirus (PorPV), Encephalomyocarditis virus (EMCV) and Leptospira spp. antibodies. Using a hemagglutination inhibition test, we registered 2.3% and 27% seropositivity for PorPV and EMCV, respectively. Using viral neutralization tests, we registered 5.8% and 47% seropositivity for PorPV and EMCV, respectively. For Leptospira spp., we registered a seropositivity of 38.8%. The variables (sex, age, years of exposure, number of visited farms, biosecurity level and region) showed no significant effect (P > 0.05) on the seropositivity for EMCV, PorPV and Leptospira spp. except for number of visited farms on HI seropositivity for EMCV (P < 0.05; odds ratio: 1.38). The data obtained provide information on the epidemiology of emerging diseases with zoonotic potential in occupational risk groups. 相似文献