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1.
LEA (Late Embryogenesis Abundant) proteins are abundant in plants and play a crucial role in abiotic stress tolerance. In our work, we primarily focused on the variations in physiochemical properties, conserved domains, secondary structure, gene ontology and evolutionary relationships among 40 LEA proteins of Triticum aestivum (common wheat). Wheat LEA protein belongs to first 6 classes out of the 13 classes present in LEApdB, the comprehensive database for LEA proteins. Proteins belonging to each LEApdB class have structures and functions distinguished from other classes. The study found three different conserved LEA domains in Triticum aestivum. One important domain was dehydrin, present in wheat proteins of classes 1, 2 and 4, though varied in sequence level, have similar biological processes. The study also found sequence level and phylogenetic similarity between dehydrin domains of class 1 and 4, but distinct from that of LEApdB class 2. This study also demonstrated functional diversity in two class 6 proteins occurred due to many destabilizing mutations in the LEA4 domain that caused alteration of ligand binding and conformational shift from 310-helix → turn within the domain. The LEA4 domains of these proteins also showed functional similarity and evolutionary relatedness with three other proteins of genus Aegilops, denoting that these proteins in Triticum aestivum were derived from its ancestor Aegilops. The study also assigned LEApdB class 4 to an unclassified LEA protein ‘WZY2-1’ based on amino acid composition, conserved domain, motif architecture and phylogenetic relatedness with class 4 proteins. Our study has revealed a detailed analysis of LEA proteins in Triticum aestivum and can serve as a pillar for further investigations and comparative analysis of wheat LEA proteins with other cereal or plant types.  相似文献   
2.
Ginkgo leave, a naturally abundant resource, has been successfully employed as the raw material to prepare nitrogen doped porous carbon (NDPC) materials. The preparation of the porous carbon does not involve assistance of any activation or template technique. The as‐obtained NDPC shows favorable features for electrochemical energy storage, which can not only provide multiple sites for the storage and insertion of Li ions, but also facilitate rapid mass transport of electrons and Li ions. As a result, the NDPC when evaluated as an anode material for lithium ion batteries delivers high reversible capacity (505 mAh·g?1 at 0.1 C), excellent rate capability (190 mAh·g?1 at 10 C). These favorable properties suggest that the NDPC can be a promising anode material for lithium ion batteries (LIBs).  相似文献   
3.
Chunhua Li  Ergen Liu 《代数通讯》2013,41(9):3090-3103
Motivated by studying fuzzy congruences in groups, semigroups, and ordered semigroups, and as a continuation of N. Kuroki and Y. Tan's works in regular semigroups in terms of fuzzy subsets, in this article we introduce the notions of a fuzzy good congruence relation, a fuzzy cancellative congruence relation on abundant semigroups, and give some properties, and characterizations of fuzzy good congruences on such semigroups. Furthermore, we characterize fuzzy good congruences of left semiperfect abundant semigroups, and get sufficient and necessary conditions for an abundant semigroup to be left semiperfect.  相似文献   
4.
Cu2ZnSn(SxS1?x)4 (CZTSSe) thin films were prepared by annealing a stacked precursor prepared on Mo coated glass substrates by the sputtering technique. The stacked precursor thin films were prepared from Cu, SnS2, and ZnS targets at room temperature with stacking orders of Cu/SnS2/ZnS. The stacked precursor thin films were annealed using a tubular two zone furnace system under a mixed N2 (95%) + H2S (5%) + Se vaporization atmosphere at 580 °C for 2 h. The effects of different Se vaporization temperature from 250 °C to 500 °C on the structural, morphological, chemical, and optical properties of the CZTSSe thin films were investigated. X-ray diffraction patterns, Raman spectroscopy, and X-ray photoelectron spectroscopy results showed that the annealed thin films had a single kesterite crystal structure without a secondary phase. The 2θ angle position for the peaks from the (112) plane in the annealed thin films decreased with increasing Se vaporization temperature. Energy dispersive X-ray results showed that the presence of Se in annealed thin films increased from 0 at% to 42.7 at% with increasing Se vaporization temperatures. UV–VIS spectroscopy results showed that the absorption coefficient of all the annealed thin films was over 104 cm?1 and that the optical band gap energy decreased from 1.5 eV to 1.05 eV with increasing Se vaporization temperature.  相似文献   
5.
The electron capture rates of 55Co and 56Ni in the ultra-strong magnetic field at four typical temperature- density points have been calculated using the nuclear shell model and Landan energy levels quantized approximate correction. The results show that the electron capture rates of 55Co and 56Ni are increased greatly in the ultra-strong magnetic field, and even exceed two orders of magnitude in the range from 4.414×10^13G to 2.207×10^27 G. The change rate of electron abundance, ye, of 55Co and 56Ni under the condition of B=4.414×10^15G in the magnetar surrounding has been calculated and discussed, the proportions of ye of 55Co and 56Ni in the total Ye have been reduced by 50 percent in all more than the condition without a magnetic field.  相似文献   
6.
喻秉钧 《数学学报》2012,(2):321-340
研究范畴与半群通过幂等元双序建立的一种自然联系.对每个有幂等元的半群S,其幂等元生成的左、右主理想之集通过双序ω~e,ω~r自然确定两个有子对象、有像且每个包含都右可裂的范畴L(S),R(S),其中态射的性质与S中元素的富足性、正则性有自然对应.利用这个联系,我们定义了"平衡(富足、正规)范畴"概念.对任一平衡(富足、正规)范畴■,我们构造其"锥半群"■,证明■左富足(富足、正则),且每个平衡(富足、正规)范畴■都与某左富足(富足、正则)半群S的左主理想范畴L(S)(作为有子对象的范畴)同构.  相似文献   
7.
In most diseases, the clinical need for serum/plasma markers has never been so crucial, not only for diagnosis, but also for the selection of the most efficient therapies, as well as exclusion of ineffective or toxic treatment. Due to the high sample complexity, prefractionation is essential for exploring the deep proteome and finding specific markers.In this study, three different sample preparation methods (i.e., highly abundant protein precipitation, restricted access materials (RAM) combined with IMAC chromatography and peptide ligand affinity beads) were investigated in order to select the best fractionation step for further differential proteomic experiments focusing on the LMW proteome (MW inferior to 40,000 Da). Indeed, the aim was not to cover the entire plasma/serum proteome, but to enrich potentially interesting tissue leakage proteins. These three methods were evaluated on their reproducibility, on the SELDI-TOF-MS peptide/protein peaks generated after fractionation and on the information supplied.The studied methods appeared to give complementary information and presented good reproducibility (below 20%). Peptide ligand affinity beads were found to provide efficient depletion of HMW proteins and peak enrichment in protein/peptide profiles.  相似文献   
8.
In plasma proteomics, before a proteome analysis, it is essential to prepare protein samples without high‐abundance proteins, including albumin, via specific preparation techniques, such as immunoaffinity capture. However, our preliminary experiments suggested that functional changes with use alter the ability of the immunoaffinity column. Thus, in this study, to evaluate the changes of the removal ability of abundant proteins from plasma by the immunoaffinity column, plasma proteome analysis was performed for the long‐term test for the reproducibility of the affinity column using the fluorogenic derivatization–liquid chromatography–tandem mass spectrometry method combined with an IgY column. The specific adsorption for albumin decreased with an increase in the number of the column usage before its expiration date. Moreover, it was demonstrated that hydrophobic high molecular weight compounds in plasma adsorbed onto the column materials surface contributed to the functional changes from specific immunoaffinity adsorption into hydrophobic interaction. These results suggested that, in quantitative plasma proteomics studies, it is important to keep in mind the risk of not only the nonselective loss but also the changes in the adsorption ability of the immunoafinity column. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
9.
本文讨论了每个元都有幂等元作为右单位元的左消半群与幂单半群N的Schuzenberger积M◇N的ρ类,证明了这种半群M与N的Schuzenberger积M◇N的ρ类是右E一半适合半群和弱E-headged半群.  相似文献   
10.
具有某种断面的半群的研究进展   总被引:1,自引:0,他引:1  
汪立民 《数学进展》2002,31(6):485-494
本文综述了几类具有特殊断面的半群的近期研究结果。在介绍逆半群和正则半群的一般结构之后,概述了具有逆断面的正则半群的结构和同余格的研究成果。总结了作为逆断面的推广的可裂断面,纯正断面,正则^*-断面和恰当断面。提出了可以进一步研究的重要的问题。  相似文献   
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