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71.
In this study, cotton/nylon blended fabrics were treated with atmospheric air plasma at various times (30–60 s) and were subsequently printed with pastes containing carbon black nanoparticles. Properties of plasma treated fabrics such as visible-near infrared (Vis-NIR) reflectance, water contact angle, air permeability, and color fastness were measured. It was shown that increasing plasma treatment time decreases reflection level of treated fabrics in Vis-NIR region. Plasma treatment also enhanced the hydrophobicity of cotton/nylon fabrics observed by an increase in water contact angle. Plasma treated samples for 60 s demonstrated lower air permeability than those treated for 30 s. Furthermore, printed samples possessed acceptable levels of fastness against washing, light and crocking.  相似文献   
72.
Background:Immobilization is an approach in industry to improve stability and reusability of urease. The efficiency of this technique depends on the type of membrane and the method of stabilization. Methods:The PEI-modified egg shell membrane was used to immobilize urease by absorption and glutaraldehyde cross-linking methods. The membranes were characterized by FTIR and AFM, and Nessler method was applied to measure the kinetic of the immobilized enzymes. Finally, the storage stability (6 °C for 21 days) and reusability (until enzyme activity reached to zero) of the immobilized enzymes were investigated. Results:Based on FTIR, three new peaks were observed in both the absorption- (at 1389.7, 1230.8, and 1074.2 cm-1) and the cross-linking (at 1615-1690, 1392.7, 1450 cm-1) immobilized enzymes. The surface roughness of the native membrane was altered after PEI treatment and enzyme immobilization. The optimal pH of cross-linking immobilized enzymes was shifted to a more neutral pH, while it was alkaline in adsorption-immobilized and free enzymes. The reaction time decreased in all immobilized enzymes (100 min for free enzyme vs. 60 and 30 min after immobilizing by adsorption and cross-linking methods, respectively). The optimal temperature for all enzymes was 70 °C and they had a higher Km and a lower Vmax than free enzyme. The stability and reusability of urease were improved by both methods. Conclusion:Our findings propose these approaches as promising ways to enhance the urease efficiency for its applications in industries and medicines. Key Words: Egg shell, Immobilization, Polyethylenimine, Urease  相似文献   
73.
In Northern Iran paddy fields, waterlogging is a serious problem. Provision of subsurface drainage seems to be a prerequisite for optimal crop production. Considering specific characteristics of the paddies, application of a suitable equation for planning of subsurface drainage systems is of great importance. In this study, five steady-state equations including Hooghoudt, Kirkham, Dagan, Ernst, and Ernst–Hooghoudt; and three unsteady-state equations including Glover–Dumm, Van-Shilfgard, and De-zeeuw–Hellinga were implemented to compute drain spacing. Required field data were obtained from 52 ha of paddy fields of “Haraz Human-Agriculture Resources Development Center,” located in Mazandaran province of Iran. The computed drain spacings were evaluated using dynamic equilibrium concept and DRAINMOD model. The minimum and maximum drain spacings were found to be 26 and 63 m corresponding to Glover–Dumm and Ernst equations, respectively. Based on the dynamic equilibrium concept, the averages of the computed water table depths for the drain spacings obtained by the unsteady-state equations were 0.5–0.63 m as compared with those obtained by the steady-state methods which were in the range of 0–0.43 m. According to the DRAINMOD model simulations, the maximum relative yield was 80.2 % which was obtained when the drain spacing was 26 m and it reduced to 73.5 % when the drain spacing was increased to 63 m. The computed drain spacings suggested by the unsteady-state equations were found to be more suitable than those obtained from the steady-state equations for the study area.  相似文献   
74.
Background: Multiple sclerosis (MS) is known as a progressive central nervous system inflammatory disease. Certain factors, such as interleukins, inflammatory cells, and oxidative stress are supposed to involve in MS etiology. Because of the important role of oxidative stress, antioxidant therapy for MS has received more attention. Although coenzyme Q10 (CoQ10) acts as an antioxidant, there is a lack of enough research on its effects on MS. Therefore, the present research was designed. Methods: C57BL/6 female adult mice (n = 30) were used in this study. The animals were randomly divided into trial and control groups. To induce MS, routine procedure for experimental autoimmune encephalomyelitis (EAE) was used, and scoring was performed based on clinical signs. By detecting score one, CoQ10 administration was started (10 mg/kg/three weeks). By using ELISA and real-time PCR, the brain levels of TNF-, IL-10, IL-4, and IL-12 were studied. Statistical tests were used to analyze the data and the P value less than 0.05 was considered to be significant. Results: Clinical symptoms in EAE animals were significantly decreased (P<0.05) as compared to control ones. In addition, the level of the TNF- was significantly decreased following CoQ10 administration versus IL-10. The ratio of TH1/TH2 interleukins in treated animals was significantly less than that in non-treated animals (P<0.01). Conclusion: Our findings showed that CoQ10 is capable of suppressing the inflammatory pathway of MS. Key Words: Experimental autoimmune encephalomyelitis (EAE), Multiple Sclerosis (MS), Coenzyme Q10 (CoQ10)  相似文献   
75.
Background:Flagellated protozoan of the genus Leishmania is the causative agent of vector-borne parasitic diseases of leishmaniasis. Since the production of recombinant pharmaceutical proteins requires the cultivation of host cells in a serum-free medium, the elimination of FBS can improve the possibility of large-scale culture of Leishmania parasite. In the current study, we aimed at evaluating a new serum-free medium in Leishmania parasite culture for future live Leishmania vaccine purposes. Methods:Recombinant L. tarentolae secreting PpSP15-EGFP and wild type L. major were cultured in serum-free (CSFM) and serum-supplemented medium. The growth rate, protein expression, and infectivity of cultured parasites in both conditions was then evaluated and compared. Results:Diff-Quick staining and epi-fluorescence microscopy examination displayed the typical morphology of L. major and L. tarentolae-PpSP15-EGFP promastigote grown in CSFM medium. The amount of EGFP expression was similar in CSMF medium compared to M199 supplemented with 5% FBS in flow cytometry analysis of L. tarentolae-PpSP15-EGFP parasite. Also, a similar profile of PpSP15-EGFP proteins was recognized in Western blot analysis of L. tarentolae-PpSP15-EGFP cultured in CSMF and the serum-supplemented medium. Footpad swelling and parasite load measurements showed the ability of CSFM medium to support the L. major infectivity in BALB/C mice. Conclusion:This study demonstrated that CSFM can be a promising substitute for FBS supplemented medium in parasite culture for live vaccination purposes. Key Words: Growth rate, L. major, L. tarentolae, Serum-free medium, PpSP15-EGFP protein  相似文献   
76.
Polyvinylidene fluoride (PVdF) membranes in spite of having many critical properties necessary for lithium-ion batteries, do not have satisfying thermal and mechanical resistance. The goal of this study was to combine the good mechanical and thermal properties of PP nonwoven fabric with the excellent electrochemical properties of PVdF nanofibers to exploit a high-performance membrane for lithium-ion batteries. This work reports the preparation of PVdF nanofiber membranes using electrospinning on a polypropylene (PP) spunbonded nonwoven fabric and an aluminum foil followed by a hot-pressing treatment. The morphology and size of the membranes were studied by the scanning electron microscopy. The tensile strength of the membrane with the PP support was superior to the PVdF membrane. Thermal stability of the prepared membranes was determined using the TGA method and the dimensional stability was investigated by measuring the shrinkage ratio at 105 °C. The results have shown that the PVdF/PP membrane was thermally more stable than the PVdF and the commercial Celgard 2325 membranes. The batteries using PVdF/PP membrane exhibited higher electrochemical oxidation limit, better cycling performance and less discharge capacity fading during 100 cycles compared to PVdF and Celgard membranes. The results of this study showed that PVdF/PP membrane is a promising advanced membrane in lithium-ion batteries.  相似文献   
77.
ABSTRACT Observations using light microscopy showed that approximately 30% of Botrytis cinerea conidia treated with semi-lethal concentrations (i.e., 60 mug/ml) of the grapevine phytoalexin resveratrol possessed intracellular brown coloration. This coloration was never observed in the absence of resveratrol or in conidia treated with resveratrol together with sulfur dioxide (antioxidant compound) or sodium diethyldithiocarbamate (inhibitor of laccase action), suggesting that discoloration resulted from the laccase-mediated oxidation of resveratrol. Further studies using transmission electron microscopy enabled the observation of particular intravacuolar spherical vesicles and of granular material deposits along the tonoplast. These observations are likely to be related to the oxidation of resveratrol by an intracellular laccase-like stilbene oxidase of B. cinerea.  相似文献   
78.
The development of genotypes with adaptation to a wide range of environments is one of the most important goals of plant breeding programs. In order to compare nonparametric stability measures and to identify promising high-yield and stable barley (Hordeum vulgare L.), 20 barley genotypes selected from the Iran/ICARDA joint project and grown in nine environments during 2009-11 in Iran. Four nonparametric statistical tests of significance for genotype × environment (GE) interaction and 10 nonparametric measures of stability were used to identify stable genotypes in nine environments. Results of nonparametric tests of G×E interaction (Kubinger, Hildebrand, and Kroon/ Laan) and a combined ANOVA across environments, indicated the presence of both crossover and non-crossover interactions. Also, only TOP and rank-sum values were positively associated with high yield. Thus, in the simultaneous selection for high yield and stability, only the rank-sum and TOP methods were useful in terms of the principal component analysis results, and correlation analysis of nonparametric stability statistics and yield. According to these stability parameters (TOP and rank-sum), three genotypes (G13, G12, and G17) were the most stable for grain yield. The results also revealed that based on nonparametric test results, stability could be classified into three groups, according to agronomic and biological concepts of stability.  相似文献   
79.
Soil pore size distribution(SPSD) is one of the most important soil physical properties. This research investigated the relationships of location and shape parameters of the SPSD curves with plant-available water(PAW) and least limiting water range(LLWR) of the light-textured soils at the Torogh Agricultural Research Station in north-eastern Iran. Soil moisture release curve(SMRC), PAW and LLWR in matric heads of 100 and 330 h Pa for the field capacity and location and shape parameters of the SPSD curves of 30 soils with different texture and organic carbon contents were determined, and the variable relationships were statistically analyzed. The results showed that the median equivalent pore diameter(de), mean de, standard deviation(SD*), and skewness of the SPSD curves were significantly correlated with PAW(PAW330) and LLWR(LLWR330) measured in a matric head of 330 h Pa. Decrease in deand increase in the diversity of soil pore size(SD*) increased PAW330 and LLWR330. The SD* values of all the soil samples were lower than the optimal ranges suggested in literature. Neither PAW nor LLWR values were significantly different in the soils with the optimal modal deand those with non-optimal modal de. Optimal values of median and mean equivalent pore diameters and kurtosis of SPSD curves led to a significant improvement of PAW330 and LLWR330 as soil physical quality indicators. It was recommended to revise the optimal ranges for SD* and modal defor future studies.  相似文献   
80.
Direct-fed microbials(DFM), generally regarded as safe status, are successfully used in improving rumen ecology, gastro-intestinal health, feed efficiency, milk production and growth rate in ruminants. On the other hand, methanogenesis in rumen, which accounts for a significant loss of ruminant energy and increased greenhouse gas in environment, is of great concern, therefore, use of DFM for improving productivity without compromising the animal health and ecological sustainability is encouraged. The present study was conducted to investigate the methane reducing potential of bacteriocinogenic strain Pediococcus pentosaceus-34. Since, the culture showed no hemolysis on blood agar and DNase activity, hence, it was considered to be avirulent in nature, a prerequisite for any DFM. The culture also showed tolerance to pH 5.0 for 24 h with 0.5% organic acid mixture, whereas when given a shock for 2 h at different p H and organic acids concentrations, it showed growth at pH 3.0 and 4.0 with 0.1 and 1.0% organic acids, respectively, as having good animal probiotics attributes. The total gas production was significantly(P<0.05) higher in live pedicoccal culture(LPC) and dead pedicoccal culture(DPC) both with wheat straw, when compared to the control. In sugarcane bagasse, gas production was significantly lower(P<0.05) with LPC compared to the control and DPC both. Methane was reduced by the inclusion of LPC in sugarcane bagasse(0.07 mL CH4 mg–1 dry matter digestibility) with no effect on other rumen fermentation parameters. However, with wheat straw and LPC total gas, in vitro dry matter digestibility, total volatile fatty acids increased significantly but no reduction in methane production was observed in comparison to the control. Therefore, further research is warranted in this direction, if the bacteriocinogenic strains can be used as DFM for ruminants to improve the ruminant productivity.  相似文献   
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