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Molecular Biology Reports - Gastric cancer is one of the common types of cancer around the world which has few therapeutic options. Nitrogen heterocyclic derivatives such as thiazoles are used as...  相似文献   
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Water super absorbents are low cross-linked hydrophilic polymers that absorb water in amounts up to several hundred times their dry weight. In this study, the effect of adding these materials to the bed of a biofilter was investigated. Two equal size biofilters were used for this purpose. One of the biofilters was packed with a mixture of perlite and a commercial polyacrylamide based super absorbent (2.3% dry weight), and the other was packed with perlite to perform as a control. The biofilters were inoculated with a bacterial culture that was able to grow on n-hexane as the sole source of carbon and energy. Both biofilters removed up to 90% of the entering pollutants when using an inlet n-hexane concentration of 1 g/m3, and an air flow rate of 0.3 L/min (mass loading of 18.34 g/m3/h, and empty bed residence time of 3.27 min). The super absorbent had a positive effect on the performance of the biofilter. While the difference in the performance of the biofilters was marginal when frequent moistening was applied, the difference was considerable when moistening was less frequent.  相似文献   
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Salinity is a major problem of many agricultural lands that is usually associated with drought stress in arid and semi-arid regions. In this study we examine the role of salinity stress on temperature requirements of two herbaceous species and how it could be modeled to quantify alterations. We applied four non-linear regression models (segmented, beta, beta modified, and dent-like) to describe the germination rate–temperature relationships of Silybum marinum L. and Calendua officinalis L. over six constant temperatures exposed to different levels of salinity stress. Our results revealed that salinity could affect the cardinal temperatures in both plants and, as a result, it is not possible to suggest one model for all levels of salinity stress. The best model to fit data to predict cardinal temperatures of Silybum marianum and Calendula officinalis at the no-salinity condition were dent-like (AICc?=?4.03) and beta (AICc = ??2.30), respectively. Knowing the thermal time constant (fo) value helps us predict the minimum number of hours required for completion of germination at the optimal temperature. All models in this study were estimated higher fo due to higher salinity stress in both Silybum marianum and Calendula officinalis seeds. The highest estimated fo for Silybum marianum (91.5?±?59.6) and Calendula officinalis (178.9?±?26.5) was obtained from the results of germination rate prediction using a dent-like model at 200 mM salinity.  相似文献   
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Plasmonics - The original version of this article unfortunately contained a mistake. The name of the fourth author is written reversely. The complete name of the fourth author is as follows:...  相似文献   
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Plasmonics - Metamaterial perfect absorbers (MPAs) with dynamic thermal tuning features are able to control the absorption performance of the resonances, providing diverse applications spanning...  相似文献   
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Thymus daenensis Celak. is an aromatic herb used as a popular medicine and its natural products in the form of extracts and essential oil have significant economic values in Iran. We hypothesized that spraying plants grown under deficit irrigation system with chitosan can be considered as an applicable method to enhance essential oil and antioxidant activity in thyme. Response of thyme to three irrigation regimes including well-watered, moderate stress, and severe stress along with three levels of chitosan application rates 0, 200, and 400 μL L?1 was evaluated in a 2-year study in 2014 and 2015. Drought stress condition significantly shortened phenologic stages, more specifically in the first (establishment) year. All growth parameters were reduced dramatically as drought stress intensified. Imposing even moderate stress reduced leaf area as much as 59 and 44% in the first year and the second year, respectively. Biomass yield of plants grown under severe drought stress decreased substantially, whereas essential oil content and the share of thymol in thyme oil which possesses the greatest degree of biological activity improved. Maximum oil yield (1.50 g plant?1) was obtained from plants under mild drought stress when sprayed with 400 μL L?1 chitosan in the second year when plants were well-established. Foliar applications of chitosan reduced the adverse effect of water deficit on oil yield and improved thymol content of the essential oil. Chitosan also increased secondary metabolites including α-terpinene, p-cymene, γ-terpinene, thymol, carvacrol and β-caryophyllene. Leaf flavonoid reduced under deficit irrigation while more phenol was found in plants grown under deficit irrigation. The essential oil of thyme exhibited antioxidant property when the plants were sprayed with 400 μL L?1 chitosan. The results of this study indicated that thyme can be grown successfully under moderate stress and that application of chitosan elicitor can to some degree compensate the negative impact of deficit irrigation on its biomass and essential oil yield.  相似文献   
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It has already been reported that in vivo muscle necrosis induced by various phenylenediamine derivatives correlated with their in vitro autoxidation rate [9]. Now in a more detailed investigation of the cytotoxic mechanism of a ring-methylated phenylenediamine known as tetramethylphenylenediamine or durenediamine (DD) towards isolated rat hepatocytes has been carried out. Cytotoxicity was preceded by ROS formation which was markedly increased by inactivating DT-diaphorase or catalase but were prevented by a subtoxic concentration of the mitochondrial respiratory inhibitor cyanide. This suggests that ROS generation could be attributed to a futile two-electron redox cycle involving oxidation of phenylenediamine to the corresponding diimine by the mitochondrial electron transfer chain and re-reduction by the DT-diaphorase. Endocytosis inhibitors, lysosomotropic agents or lysosomal protease inhibitors also prevented DD-induced cytotoxicity suggesting that DD-induced ROS caused lysosomal damage and protease activation in hepatocytes. Furthermore preincubation with deferoxamine (a ferric iron chelator) or addition of antioxidants, catalase or ROS scavengers (mannitol, tempol or dimethylsulfoxide) prevented DD cytotoxicity. These results suggest that H(2)O(2) reacts with lysosomal Fe(2+) to form "ROS" which causes lysosomal lipid peroxidation, membrane disruption, protease release and cell death.  相似文献   
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