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81.
In the present study Cervatana and Almagra models from decision support system, MicroLEIS DSS, were applied to segregation of arable land surfaces from the marginal ones and suitability evaluation of wheat (Triticum aestivum), maize (Zea mays) and alfalfa (Medicago sativa) in Souma area with approximately 4100 ha extension in West Azarbaijan. Obtained results from both models are presented and discussed in this research work. Soil morphological and analytical data were collected from 35 soil profiles, representative of the study area and stored in SDBm plus database. The control or vertical section of soil for applying and running the models for annual selected crops, was calculated by soil layer generator 0.0–50 cm in depth, or between the surface and the limit of useful depth when the latter is between 0.0 and 50 cm. According to results, 80.49% of the total area was good capable for agricultural uses and 19.51% must be reforested and not dedicated to agriculture. The lands with good capability for agricultural uses is classified as highly suitable area (S2) for wheat, maize and alfalfa, but results in 822 ha for maize and in 126 ha for alfalfa refers to an excellent suitable (S1) and moderately suitable (S3) classes respectively. The most important limitation factors are soil texture and carbonate alone or together and maize — wheat — alfalfa can be selected as the best crop rotation. A simple map subsystem (ArcView GIS) was used for basic data and models result demonstration on a map.  相似文献   
82.
Strong electron‐donating functionality is desirable for many organic donor‐π‐bridge‐acceptor (D‐π‐A) dyes. Strategies for increasing the electron‐donating strength of common nitrogen‐based donors include planarization of nitrogen substituents and the use of low resonance‐stabilized energy aromatic ring‐substituted nitrogen atoms. Organic donor motifs based on the planar nitrogen containing heterocycle indolizine are synthesized and incorporated into dye‐sensitized solar cell (DSC) sensitizers. Resonance active substitutions at several positions on indolizine in conjugation with the D‐π‐A π‐system are examined computationally and experimentally. The indolizine‐based donors are observed to contribute electron density with strengths greater than triarylamines and diarylamines, as evidenced by UV/Vis, IR absorptions, and oxidation potential measurements. Fluorescence lifetime studies in solution and on TiO2 yield insights in understanding the performance of indolizine‐based dyes in DSC devices.  相似文献   
83.
Stearoyl‐CoA desaturase 1 (SCD1) plays important roles in organ development, glucose tolerance, insulin sensitivity, and cancer. Here, we examined the role of SCD1 for the differentiation of human induced pluripotent stem (hiPS) cells to liver cells by using drug inhibition and biochemical experiments. hiPS cells cultured in a pro‐hepatic medium were exposed to an SCD1 inhibitor at various stages throughout differentiation. Liver‐specific markers, specifically α‐fetoprotein, albumin and urea in conditioned medium, and hepatocyte nuclear factor 4α (HNF4α) and cytochrome P450 7A1 (CYP7A1) gene expressions and triglyceride in cellular extracts were analyzed at various development stages. Measures of hepatocyte‐specific function and triglyceride accumulation in later stages were strongly inhibited a minimum of −29% (< 0.05) by SCD1 inhibitor in the early stage of hepatic differentiation and effectively reversed (>30%, P < 0.01) by the addition of oleate. The results were also reproducible with human primary mononuclear cells (hPMN). SCD1 inhibitor had no significant effect on liver‐specific markers when it was added in the hepatic maturation stage. However, it strikingly led to higher albumin (1.6‐fold, = 0.03) and urea (1.9‐fold, = 0.02) production, and HNF4α (1.9‐fold, = 0.02) and CYP7A1 (1.3‐fold, = 0.03) expression upon incubation during the lineage‐commitment stage. Hepatic differentiation from cultured hiPS cells is sensitive to SCD1 inhibition and this sensitivity is affected by the stage of cellular differentiation. Notably, findings also indicate that this notion can be extended to hPMN. The requirement for SCD1 activity in functional differentiation of hepatocytes may have relevance for human liver disease and metabolic dysregulation.  相似文献   
84.
The rod outer segment (OS), comprised of tightly stacked disk membranes packed with rhodopsin, is in a dynamic equilibrium governed by a diurnal rhythm with newly synthesized membrane inserted at the OS base balancing membrane loss from the distal tip via disk shedding. Using transgenic Xenopus and live cell confocal imaging, we found OS axial variation of fluorescence intensity in cells expressing a fluorescently tagged rhodopsin transgene. There was a light synchronized fluctuation in intensity, with higher intensity in disks formed at night and lower intensity for those formed during the day. This fluctuation was absent in constant light or dark conditions. There was also a slow modulation of the overall expression level that was not synchronized with the lighting cycle or between cells in the same retina. The axial variations of other membrane-associated fluorescent proteins, eGFP-containing two geranylgeranyl acceptor sites and eGFP fused to the transmembrane domain of syntaxin, were greatly reduced or not detectable, respectively. In acutely light-adapted rods, an arrestin-eGFP fusion protein also exhibited axial variation. Both the light-sensitive Rho-eGFP and arrestin-eGFP banding were in phase with the previously characterized birefringence banding (Kaplan, Invest. Ophthalmol. Vis. Sci. 21, 395–402 1981). In contrast, endogenous rhodopsin did not exhibit such axial variation. Thus, there is an axial inhomogeneity in membrane composition or structure, detectable by the rhodopsin transgene density distribution and regulated by the light cycle, implying a light-regulated step for disk assembly in the OS. The impact of these results on the use of chimeric proteins with rhodopsin fused to fluorescent proteins at the carboxyl terminus is discussed.  相似文献   
85.
Although the insertion of heme into proteins enables their function in bioenergetics, metabolism, and signaling, the mechanisms and regulation of this process are not fully understood. We developed a means to study cellular heme insertion into apo-protein targets over a 3-h period and then investigated how nitric oxide (NO) released from a chemical donor (NOC-18) might influence heme (protoporphyrin IX) insertion into seven targets that present a range of protein structures, heme ligation states, and functions (three NO synthases, two cytochrome P450's, catalase, and hemoglobin). NO blocked cellular heme insertion into all seven apo-protein targets. The inhibition occurred at relatively low (nM/min) fluxes of NO, was reversible, and did not involve changes in intracellular heme levels, activation of guanylate cyclase, or inhibition of mitochondrial ATP production. These aspects and the range of protein targets suggest that NO can act as a global inhibitor of heme insertion, possibly by inhibiting a common step in the process.  相似文献   
86.
Phosphodiesterase inhibitors (PDEIs) are a class of drugs that are widely used because of their various pharmacological properties including cardiotonic, vasodilator, smooth muscle relaxant, antidepressant, antithrombotic, bronchodilator, antiinflammatory and enhancer of cognitive function. In the recent years, interest in drugs of plant origin has been progressively increased. Some pharmacologically active substances that come from plants demonstrate PDEI activity. They mainly belong to alkaloids, flavonoids, and saponins. In this review, studies on herbal PDEI were reviewed and their possible therapeutic applications were discussed. Screening plants for PDE inhibitory activity may help to develop standardized phytotherapeutic products or find new sources for new lead structures with PDEI pharmacological activity. The studies discussed in this paper are mainly in vitro and for more reasonable and conclusive results, it is required to conduct in vivo and finally human and clinical tests.  相似文献   
87.
Biomechanics and Modeling in Mechanobiology - Blood flow analysis in the artery is a paramount study in the field of arterial stenosis evaluation. Studies conducted so far have reported the...  相似文献   
88.
89.
Water stress is one of the main abiotic factors that reduces plant growth, mainly due to high evaporative demand and low water availability. In order to evaluate the effects of drought stress on certain morphological and physiological characteristics of two canola cultivars, we conducted a factorial experiment based on a completely randomized design. The findings show that drought stress exacerbations result in the plant's response to stress due to increased canola resistance caused by changes in plant pigments, proline, catalase, ascorbate peroxidase, peroxidase, superoxide dismutase and malondialdehyde, glucose, galactose, rhamnose and xylose. These in turn ultimately influence the morphological characteristics of canola. Drought stress reduces the concentration of carotenoids, chlorophyll a, chlorophyll b, total chlorophylls; however, glucose, galactose, rhamnose, xylose, proline, catalase, ascorbate peroxidase, peroxidase, superoxide dismutase, malondialdehyde (in leaves and roots) and the chlorophyll a and b ratios were increased. Reduction of plant height, stem height, root length, fresh and dry weight of canola treated with 300 g/l PEG compared to non‐treatment were 0.264, 0.236, 0.394, 0.183 and 0.395, respectively. From the two canola cultivars, the morphological characteristics of the NIMA increased compared to the Ks7 cultivar. Interaction effects of cultivar and drought stress showed that NIMA cultivar without treatment had the highest number of morphological characteristics such as carotenoid concentration, chlorophyll a, chlorophyll b, total chlorophylls a and b, whereas the cultivar with 300 g/l PEG (drought stress) had the highest amount of proline, malondialdehyde, soluble sugars and enzymes in leaves and roots. Increasing activity of oxidative enzymes and soluble sugars in canola under drought stress could be a sign of their relative tolerance to drought stress.  相似文献   
90.
International Journal of Peptide Research and Therapeutics - Acinetobacter baumannii is an important pathogen responsible for nosocomial infections worldwide. Trimeric autotransporters, the...  相似文献   
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