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111.
Three geomorphological models, based on linear reservoirs cascade, are developed; two of the models are unit hydrograph (UH) models and one contains a non-linear routing approach. In the first UH model, each sub-basin is represented as a cascade of equal linear reservoirs (Nash's model) which directly discharges to the watershed outlet through a linear channel. In the second UH model each sub-basin is represented as a linear reservoir arranged in a sequence based on the drainage network. For both unit hydrograph models, parameters are explicitly derived, which make the models simple and applicable for real world problems. In the third model, output hydrographs of the sub-basins are calculated by the Nash model but with consideration of geomorphological properties of the sub-basins. Then, the obtained hydrographs are routed through the main channel using a non-linear kinematic wave model. Combination of the kinematic wave routing model (a non-linear routing model) and the Nash model (a linear lumped model) makes this third model more appropriate for runoff modeling.Two important properties of these three models are that they consider the effect of watershed geomorphology and include only one parameter which can be estimated using observed rainfall–runoff data. GIS tools are used for determining the watershed geomorphological parameters. The results of these models are compared with the Nash's black box and the geomorphological SCS models for the Amameh watershed, Iran. Although the results show that the proposed models yield good efficiency in rainfall–runoff modeling, the semi-distributed routing ability in the second and third models produces better results.  相似文献   
112.
Anaesthetic efficacy of eugenol was investigated on Pterophyllum scalare. A total of 130 fish with average weights of 1.0 ± 0.5, 5.0 ± 1.0 and 10.0 ± 1.0 g were subjected to 1.25, 2.5, 4.0, 5.5 and 7.0 mg/L eugenol, and behavioural responses were observed. Induction and recovery times were significantly affected by the interactive effect of eugenol concentration and fish weight (< .05). Generally, 49.9–128 s after exposure to 1.25–7 mg/L eugenol, fish reached stage 3. Fish entered stage 4 over 55–135 s post exposure to such concentrations. Recovery time was 393.5–597.7 s in all sizes. Any increase in eugenol concentration led to a significant decrease in the induction time with a subsequent increment of the recovery time. Concentrations of eugenol and fish size along with their interactive effects have significantly contributed to the regression models, with concentration recording the highest beta values for stages 1, 2, 3 and 4 (?0.903, ?0.898, ?0.976 and ?0.864 respectively) and the product of size and anaesthetic concentration for full recovery in smaller fish (0.647) and eugenol concentration in larger ones (0.967). Recovery time was fitted to induction time to stage 4 via quadratic and linear regression models in smaller and larger fish respectively. Results revealed the minimal eugenol concentration to induce anaesthesia in various size classes of angelfish in less than 3 min was 1.25 mg/L. Our results showed eugenol as an effective and safe anaesthetic; however, it is not advisable for live fish transportation.  相似文献   
113.
Background:Glioblastoma multiforme is the most invasive and lethal form of brain cancer with unclear etiology. Our study aimed to investigate the molecular prevalence of HCMV and EBV infections in patients with GBM. Methods:This case-control study was conducted on 42 FFPE brain tumor samples from GBM patients and 42 brain autopsies from subjects without neurological disorders. The presence of EBV and HCMV DNA was determined, using PCR and nested-PCR assays, respectively. Results:HCMV DNA was detected in 3 out of 42 (7.1%) of GBM samples and was absent from the control group (p = 0.07). Importantly, EBV DNA was detected in 9 out of 42 (21.4%) brain tissue specimens of GBM subjects, but again in none of the control group (p = 0.001). Conclusion:Our findings indicate that infection with EBV is associated with GBM. Key Words: Brain tumor, Epstein-Barr virus, Glioblastoma, Human cytomegalovirus  相似文献   
114.
In this study, ovarian fluid composition and its effects on the motility and fertilizing ability of sperm were studied in endangered Caspian brown trout, Salmo trutta caspius, and were compared with a saline activation medium (125 mM NaCl, 30 mM Glycine, 20 mM Tris–HCl, pH = 9.0) and freshwater as the control. The ovarian fluid was composed of sodium 164.4 ± 4.4 mM l−1, potassium 1.8 ± 0.1 mM l−1, calcium 0.6 ± 0.1 mM l−1, magnesium 0.4 ± 0.02 mM l−1, chloride 127.4 ± 5.9 mM l−1, total protein 389.5 ± 89.6 mg 100 ml−1, cholesterol 9.3 ± 1.2 mg dl−1, and glucose 3.3 ± 0.2 mM l−1. The percentage of motile spermatozoa and the duration of sperm motility were significantly higher in ovarian fluid (62 ± 3%, 74.6 ± 0.8 s) than freshwater (35 ± 4%, 44 ± 1 s), but they did not differ significantly from saline medium (56 ± 3%, 74.3 ± 0.7 s) (P > 0.05). Higher eyeing rates were observed after the activation of sperm in ovarian fluid and saline solution than freshwater when 35,000 or 350,000 spermatozoa per egg were added into the activation media. However, no significant differences were observed at higher concentrations of spermatozoa per egg (730,000) (P > 0.05). Also, this study showed that the ovarian fluid composition can be considered as a species-specific character among salmonid fishes. As a conclusion, the results of this study recommend the use of ovarian fluid or the saline solution as an activation medium in the artificial reproduction of Caspian brown trout.  相似文献   
115.
A novel activated carbon has been prepared by the activation of ground pine cones using phosphoric acid activation, and the nitrogen Brunauer?CEmmett?CTeller surface area was 869 m2 g?1. Equilibrium isotherms were performed to assess the capacity of the activated carbon using two acidic dyes, namely Acid Blue 113 and Acid Black 1. The monolayer equilibrium isotherm capacities of Acid Blue 113 and Acid Black 1 were 286 and 458 mg dye/g C, respectively. These capacities are significantly higher than commercial carbons and other literature carbons. For the first time, these carbons were tested in fixed bed experimental systems and data analysed using the bed depth service time model (BDST) and the carbon usage rate (CUR) model. In the fixed bed studies, the key parameters for a 20-cm bed depth for the BDST model at 50% breakthrough capacity are (a) for Acid Black, the BDST capacity is 149 mg dye/g carbon and operating time is 1,530 min and (b) for Acid Blue, the breakthrough capacity is 9 mg of dye/g of carbon and operating time is 195 min. The fixed bed study indicates that the BDST design models can be applied satisfactorily, and the pine cone carbon has significant potential but a more mesoporous pine cone carbon is preferable for the larger Acid Black dye. The CUR design method was not successful.  相似文献   
116.
Seed priming is a method to improve germination and seedling establishment under stress conditions. The effect of seed priming in chemical solutions such as urea and KNO3, on protein and proline content, germination, and seedling growth responses of four maize (Zea mays L.) hybrids under drought and salt stress conditions was studied in a controlled environment in 2010. Treatments included stress type and intensity at five levels: moderate drought (MD), severe drought (SD), moderate salt (MS), severe salt (SS), and control (C1, without stress), three seed priming types including water (C2, as control), KNO3, and urea (as chemical priming), and four maize hybrids including Maxima, SC704, Zola, and 307. The results showed that the highest germination percentage (Ger %), germination rate (GR), seedling length (SL), radical length (RL), and seedling to radical length ratio (S/R) were achieved in no stress treatments and most proline content in SD treatment. Urea priming led to more Ger%, GR, and SL compared to other primers and treatment under KNO3 priming resulted in higher RL compared to other primers. Chemical priming had no effect on S/R and proline content. Also, in terms of most traits, no difference was found among the four hybrids. Results showed that salt stress could affect GR and RL more than the drought stress. Drought stress affected germination percentage and S/R more than the salt stress. Both stresses decreased all measured parameters, except protein and proline content which were increased remarkably, and more under drought compared to salt stress. Based on proline content, hybrid 304 appeared to be more resistant to stress than other hybrids. Generally, KNO3 and urea alleviated effects of both stresses and led to increased germination and seedling growth as well as the root length. Therefore, priming could be recommended for enhancing maize growth responses under stressful conditions.  相似文献   
117.
The pharmacokinetics of tramadol in camels (Camelus dromedarius) were studied following a single intravenous (IV) and a single intramuscular (IM) dose of 2.33 mg kg(-1) bodyweight. The drug's metabolism and urinary detection time were also investigated. Following both IV and IM administration, tramadol was extracted from plasma using an automated solid phase extraction method and the concentration measured by gas chromatography-mass spectrometry (GC/MS). The plasma drug concentrations after IV administration were best fitted by an open two-compartment model. However a three-compartment open model best fitted the IM data. The results (means+/-SEM) were as follows: after IV drug administration, the distribution half-life (t(1/2)(alpha)) was 0.22+/-0.05 h, the elimination half-life (t(1/2)(beta)) 1.33+/-0.18 h, the total body clearance (Cl(T)) 1.94+/-0.18 L h kg(-1), the volume of distribution at steady state (Vd(ss)) 2.58+/-0.44 L kg(-1), and the area under the concentration vs. time curve (AUC(0-infinity)) 1.25+/-0.13 mg h L(-1). Following IM administration, the maximal plasma tramadol concentration (C(max)) reached was 0.44+/-0.07 microg mL(-1) at time (T(max)) 0.57+/-0.11h; the absorption half-life (t(1/2 ka)) was 0.17+/-0.03 h, the (t(1/2)(beta)) was 3.24+/-0.55 h, the (AUC(0-infinity)) was 1.27+/-0.12 mg h L(-1), the (Vd(area)) was 8.94+/-1.41 L kg(-1), and the mean systemic bioavailability (F) was 101.62%. Three main tramadol metabolites were detected in urine. These were O-desmethyltramadol, N,O-desmethyltramadol and/or N-bis-desmethyltramadol, and hydroxy-tramadol. O-Desmethyltramadol was found to be the main metabolite. The urinary detection times for tramadol and O-desmethyltramadol were 24 and 48 h, respectively. The pharmacokinetics of tramadol in camels was characterised by a fast clearance, large volume of distribution and brief half-life, which resulted in a short detection time. O-Desmethyltramadol detection in positive cases would increase the reliability of reporting tramadol abuse.  相似文献   
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120.
This study has evaluated the effects of different concentrations of the water and ethanolic extracts of Iranian propolis (WEP and EEP) on the microbiological and sensory parameters of minced common carp meat that was stored at 4°C for 9 days. The chemical compounds of the extracts were identified by gas chromatography–mass spectroscopy (GC-MS) analysis. The results revealed that WEP and EEP extracts were efficient against the spoilage microorganisms, including total plate counts (TPCs), psychrotrophic populations (PTCs), lactic acid bacteria (LAB), and even Staphylococcus aureus. There was a significant difference in the bacteria growth between samples treated with WEP or EEP and the control sample during storage. Inhibitory effects were, respectively, 7% EEP > 5% EEP > 3% EEP > 7% WEP > 5% WEP > 3% WEP. In all treatments, PTC counts were higher than 7 log CFU/g after 6 days as well as TPC, LAB, and S. aureus populations after 9 days. Overall, the results show that EEP and WEP have good antimicrobial activity due to high phenolic and flavonoid compounds, including caffeic acid, tectochrysin, aceacetin, chrysin, pinostrobin, pinobanksin-3-acetate, galangin-3-methyl ester, and pinocembrin chalcone. Sensory evaluation shows very slight improvement in sensory properties (color, odor, texture, and overall acceptability) of the treated samples with the different extracts of Iranian propolis.  相似文献   
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