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101.
This work describes the evolution of NO2 and O3 levels from January to December of 2007, covering the four seasonal periods in the urban air of Ciudad Real in the central-southern Spain. The measurements were carried out by means of passive samplers (Radiello® samplers). Eleven samples were collected weekly, placed at different monitoring site locations. The data indicate that the mean levels obtained during this period for O3 and NO2 were 38.5?±?3.5 and 20.8?±?3.8 μg/m3, respectively. These measurements were compared with other studies in Ciudad Real. Meteorological conditions (temperature, pressure, humidity relative, wind speed and direction) were also investigated.  相似文献   
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103.
BACKGROUND: Recently, two fungal proteins with apparent molecular masses of 11 and 15 kDa and insecticidal activity against Ceratitis capitata (Wied.) have been purified from the crude soluble protein extract (CSPE) secreted by the entomopathogenic fungus Metarhizium anisopliae (Metsch.) Sorokin (strain EAMa 01/58‐Su) in Adamek's liquid medium. The feasibility of culturing this strain in fermentation facilities in order to harvest and formulate the insecticidal proteins for C. capitata control is mainly dependent on the ability to produce high concentrations of the active proteins at a reasonable cost. RESULTS: These studies report that, in batch cultures of EAMa 01/58‐Su strain, the carbon (C) and nitrogen (N) ratios and sources are important considerations with respect to fungal biomass production, blastospore yield and secretion of insecticidal proteins against C. capitata adults. The data indicate that the type and concentration of N source in the medium influence the production of insecticidal protein and thus the toxicity of the CSPEs. The electrophoretic analysis suggests that the monomer of 11 kDa plays an important role in the insecticidal effect described. Concerning biomass production, no clear differences were found between media with different C and N sources and C:N ratios in total biomass production at day 7. Conversely, important differences were found among the media in terms of blastospore yields. CONCLUSIONS: By optimising the culture media, the insecticidal effect of the CSPE against C. capitata can be improved. In the CSPE from G40:P20 (40 g L?1 glucose and 20 g L?1 peptone in dH2O), the LC50 and the LT50 were 7 and 4.5 times lower than in the CSPE obtained from Adamek. Copyright © 2010 Society of Chemical Industry  相似文献   
104.
This study aimed to evaluate the effect of recipient-donor estrous cycle synchrony on recipient reproductive performance after nonsurgical deep-uterine (NsDU) embryo transfer (ET). The transfers (N=132) were conducted in recipients sows that started estrus 24 h before (–24 h; N=9) or 0 h (synchronous; N=31), 24 h (+24 h; N=74) or 48 h (+48 h; N=18) after the donors. A total of 30 day 5 morulae or day 6 blastocysts (day 0=onset of estrus) were transferred per recipient. The highest farrowing rates (FRs) were achieved when estrus appeared in recipients 24 h later than that in the donors (81.1%), regardless of the embryonic stage used for the transfers. The FR notably decreased (P<0.05) when recipients were –24 h asynchronous (0%), synchronous (61.3%) or +48 h asynchronous (50%) relative to the donors. No differences in litter size (LS) and piglet birth weights were observed among the synchronous and +24 h or +48 h asynchronous groups. While a +24 h asynchronous recipient was suitable for transfers performed with either morulae (FR, 74.3%; LS, 9.2 ± 0.6 piglets) or blastocysts (FR, 84.6%; LS, 9.8 ± 0.6 piglets), a + 48 h asynchronous recipient was adequate for blastocysts (FR, 87.5%; LS, 10.4 ± 0.7 piglets) but not for morulae (FR, 30.0%; LS, 7.3 ± 2.3 piglets). In conclusion, this study confirms the effectiveness of the NsDU-ET technology and shows that porcine embryos tolerate better a less advanced uterine environment if they are nonsurgically transferred deep into the uterine horn.  相似文献   
105.
An algorithm for selection of least cost or optimum pump combinations in water supply systems and to evaluate the system's energy cost of inland intensive fishfarms is presented. The model is based on solving a non-linear programming problem. Optimum design refers to the selection of pump type, capacity, and number of units that results in minimum design and operating costs for a given water demand curve. The optimization process consists of three main steps: (1) determination of fishfarm daily water requirements; (2) determination of all sets of pumping stations that satisfy the maximum requirements of flow and energy head of the fishfarm water distribution network; and (3) selection of the least-cost set among the feasible sets of pumping stations. The model was established based on data from an actual eel fishfarm in southern Spain. Application of the model shows that the optimal solution with the pump operation scheme at a constant rate (maximum requirements of flow) saved 70% of the actual total annual cost of the pumping station. The optimal solution with a variable pumping rate (pumped flow adjustment to match demand) saved 92% of the actual total annual cost with all fixed speed pump groups. Savings about 95% were obtained when one variable speed pump group was included in the optimal solution.  相似文献   
106.
One of the main problems in the management of fishfarms with water recirculating system is the forecasting and control of ammonia concentration in order to minimise the fish stress status. This paper examines methodologies of prediction in a real-time environment for an eel intensive rearing system. Approaches based on linear multiple regression, univariate time series models (exponential smoothing and autoregressive integrated moving average (ARIMA) models) and computational neural networks (ANNs) are developed to predict the daily average ammonia concentration in rearing tanks with water recirculating. The models are established using actual data from an eel fishfarm in southern Spain. The input variables used in the models (multiple regression, Holt smoothing model, ARIMA models and ANN models) are the ammonia concentration of previous days. In ANN models, the training method used is a standard back-propagation variation known as extended-delta-bar-delta (EDBD). Different neural architectures, whose learning is carried out by crossvalidation and controlling several threshold determination coefficients, are compared. Globally, the nonlinear ANN model approach is shown to provide a better prediction of daily average ammonia concentration than linear multiple regression and univariate time series analysis when the correlation between data series is low and when the models were obligated to predict in a situation for which specifically had not been calibrated. The best results were obtained by 5:10s:15s:1l ANN model in the pre-growth series.  相似文献   
107.
108.
The effect of the hormonal herbicide MCPA on VA mycorrhizal infection and on pea plant growth was examined. Plant growth was decreased by MCPA applied at the rate of 120 ppm. The VA infections of pea roots inoculated with G. mosseae was decreased by the MCPA when applied at high dosis (120 ppm), but those of indigenous endophytes were decreased at the rate of 12 and 120 ppm. MCPA applied to VA inoculated pots eight weeks before pea planting also decreased the VA infection of these plants. These results suggest that VA mycorrhizas was affected not only through the plant but also directly by the application of the herbicide. Glomus mosseae may help plants recover from the deleterious effect of MCPA when applied at intermediary (12 ppm) but not at high dosis (120 ppm).  相似文献   
109.
Chlorella sorokiniana has been selected for lutein production, after a screening of thirteen species of microalgae, since it showed both a high content in this carotenoid and a high growth rate. The effects of several nutritional and environmental factors on cell growth and lutein accumulation have been studied. Maximal specific growth rate and lutein content were attained at 690 μmol photons m(-2) s(-1), 28 °C, 2 mM NaCl, 40 mM nitrate and under mixotrophic conditions. In general, optimal conditions for the growth of this strain also lead to maximal lutein productivity. High lutein yielding mutants of C. sorokiniana have been obtained by random mutagenesis, using N-methyl-N'-nitro-nitrosoguanidine (MNNG) as a mutagen and selecting mutants by their resistance to the inhibitors of the carotenogenic pathway nicotine and norflurazon. Among the mutants resistant to the herbicides, those exhibiting both high content in lutein and high growth rate were chosen. Several mutants exhibited higher contents in this carotenoid than the wild type, showing, in addition, either a similar or higher growth rate than the latter strain. The mutant MR-16 exhibited a 2.0-fold higher volumetric lutein content than that of the wild type, attaining values of 42.0 mg L(-1) and mutants DMR-5 and DMR-8 attained a lutein cellular content of 7.0 mg g(-1) dry weight. The high lutein yield exhibited by C. sorokiniana makes this microalga an excellent candidate for the production of this commercially interesting pigment.  相似文献   
110.
The aim of the present work is to study whether the introduction of rosemary plant byproduct, from plant steam distillation, in daily Segurena sheep feeding allows the transfer of active antioxidant components to lamb meat, without detriment to the animal productivity. For this, 36 Segurena ewes were assigned randomly to three homogeneous groups. One group was fed a basal diet as a control and the diet of the other two groups was modified by substituting 10 or 20% of the control diet (respectively) with distilled rosemary leaves. Chromatographic analysis allowed the identification of 11 polyphenolic components previously identified in the rosemary and basal diet pellets, respectively. Among them, rosmarinic acid, carnosol, and carnosic acid were the phenolic components that had a significantly increased presence ( P < 0.05) in the lamb meat from sheep mothers fed this aromatic herb, when compared to the control group. The incorporation of this byproduct into the animal diet favored the antioxidant capacity of these lamb meat samples. Fresh meat produced on rosemary had higher total ferric reducing antioxidant power (FRAP) ( P < 0.05), greater ability to reduce ABTS*+, and lower IC50 (DPPH*) ( P < 0.05) values when compared to the control group. Because no statistically significant differences were detected among the results obtained from the lamb meat belonging to the different ewe groups fed rosemary leaf extract (10 or 20%), it can be concluded that the incorporation of distilled rosemary leaves at a rate of 10% of the ewes' diet should be enough to improve the lamb meat antioxidant status.  相似文献   
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