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451.
We have previously used the molecular‐imprinting method for the synthesis of artificial gel antibodies, highly selective for various proteins. In the present work, we have synthesized artificial gel antibodies against human albumin with the aim to develop a simple and rapid procedure to measure the concentration of this protein in samples of clinical interest. The procedure, based on the design of a standard curve (see the preceding paper), was applied on a quantitative analysis of albumin in human plasma and cerebrospinal fluid (CSF). We found that our technique permitted detection of albumin in these body fluids with high precision and that the concentration of this protein was significantly enhanced in CSF from patients with amyotrophic lateral sclerosis (ALS), compared to control samples. This finding is in agreement with results from earlier studies, which confirms the validity of our analysis technique and suggests that the barrier permeability may be affected in ALS, perhaps also for other proteins. No enhancement in plasma levels of albumin was seen in patients with ALS, but rather a decrease. The results further indicate that our approach might also apply well to other biomarkers for the actual neurological disease and other disorders. 相似文献
452.
Substituent effect on structure,stability, and aromaticity of novel BnNmC20–(n+m) heterofullerenes 下载免费PDF全文
Maryam Koohi Somayeh Soleimani Amiri Bibi Narjes Haerizade 《Journal of Physical Organic Chemistry》2017,30(11)
We are focusing our calculations on the structural stabilities and electronic properties of 26 novel BnNmC20–(n+m) heterofullerenes, with n, m = 1 ? 5, at B3LYP/6‐311++G** and B3LYP/AUG‐cc‐pVTZ levels of theory. Vibrational frequency calculations on C20 and its analogues show that except B2N2C16 (1) and B2N2C16 (2), all other heterofullerenes are true minima. The heats of atomization energies, binding energy, band gaps (ΔEHOMO‐LUMO), aromaticity, nucleus‐independent chemical shifts, thermodynamic stability, kinetic stability against electronic excitation, binding energy as a stability criterion of different configurations, geometrical parameters, conformational structures, conductivity, charge transfer, and possibility for hydrogen storage of these heterofullerenes strongly depend on their number of heteroatoms, topology, filling patterns, and locations as well as “B‐site and N‐site attachments.” B5N5C10 contains 5 alternating boron and nitrogen atoms in the equatorial position. It is predicted to be thermodynamically and kinetically the most stable against electron excites. Thus, it is energetically favorable and its electronic properties as well as stabilities make it perhaps a good candidate for an experimental investigation and testing verification. 相似文献
453.
为探究不同类型地震波作用下地下综合体结构的地震反应特征,本文以上海某地下综合体为工程背景,采用ABAQUS软件建立土-地下综合体结构相互作用体系三维有限元模型,利用Davidenkov模型模拟土的非线性,以不同类型的单向地震波和双向地震波(含水平向和竖向)作为输入,对软土场地中地下综合体结构进行了地震反应分析,比较了不同类型地震波作用下地下综合体结构地震反应的差异,探讨了地下综合体结构的竖向地震动效应问题.本文的算例结果表明:在长周期地震波作用下地下综合体结构的位移响应和内力响应峰值均明显大于普通地震波作用下的结果;考虑竖向地震动时地下综合体结构的柱轴力较单一水平向地震动作用情形有明显增大;在本文地下综合体结构算例中,地下三层柱底、四层柱顶、五层柱底、以及底板与侧墙连接处为受力较大部位. 相似文献
454.
Iman Khosravi Maryam Dashtbani Hadi Amiri Rudbari Ghazal Borhan 《Journal of Macromolecular Science: Physics》2017,56(9):655-669
The interaction of an asymmetric Schiff base ligand derived from allylamine and 2,3-dihydroxybenzaldehyde and its molybdenum (VI) complex with deoxyribonucleic acid (DNA) and bovine serum albumin (BSA) were studied using spectroscopic and molecular docking methods. The spectroscopic results revealed that the DNA and BSA affinity for binding the Mo(VI) complex is greater than its ligand. Furthermore, the molecular docking calculations showed that H-bond, hydrophobic, π-π and π-cation interactions had the dominant roles in the stability of the compound-BSA complexes. The DNA interaction results suggested that the compounds interacted with DNA by the groove binding mechanism. 相似文献
455.
In this work, we develop a macroscopic model for diffusion–migration of ionic species in saturated porous media, based on periodic homogenization. The prior application is chloride transport in cementitious materials. The dimensional analysis of Nernst–Planck equation lets appear dimensionless numbers characterizing the ionic transfer in porous media. Using experimental data, these dimensionless numbers are linked to the perturbation parameter ${\varepsilon}$ . For a weak-imposed electrical field, or in natural diffusion, the asymptotic expansion of Nernst–Planck equation leads to a macroscopic model coupling diffusion and migration at the same order. The expression of the homogenized diffusion coefficient only involves the geometrical properties of the material microstructure. Then, parametric simulations are performed to compute the chloride diffusion coefficient through different complexity of the elementary cell to go on as close as possible to experimental diffusion coefficient of the two cement pastes tested. 相似文献
456.
An experimental and numerical study has been carried out to investigate the heat transfer characteristics of a horizontal
circular cylinder exposed to a slot jet impingement of air. A square-edged nozzle is mounted parallel with the cylinder axis
and jet flow impinges on the bottom of the cylinder. The study is focused on low Reynolds numbers ranging from 120 to 1,210,
Grashof numbers up to Gr = 10Re
2 and slot-to-cylinder spacing from 2 to 8 of the slot width. The flow field is greatly influenced by the slot exit velocity
and the buoyancy force due to density change. A Mach–Zehnder Interferometer is used for measurement of local Nusselt number
around the cylinder at 10° interval. It is observed that the average Nusselt number decreases with increasing the jet spacing
and increases with rising the Reynolds number. A finite volume method utilizing a curvilinear coordinate transformation is
used for numerical modeling. The numerical results show good agreement with the experimental results. The flow and thermal
field are seen to be stable and symmetric around the cylinder over the range of parameters studied. 相似文献
457.
Somayeh Soleimani‐Amiri Zinatossadat Hossaini Maryam Arabkhazaeli Hossein Karami Saeid Afshari Sharif Abad 《中国化学会会志》2019,66(4):438-445
In this paper, we report the synthesis of pyrimido[2,1‐a] isoquinoline and pyrimido[1,2‐a]quinoline derivatives in high yields from the reaction of isoquinoline or quinoline, activated acetylenic compounds, and amides in the presence of ZnO nanorods (ZnO‐NRs) as catalyst under solvent‐free conditions at room temperature. ZnO‐NRs show good improvement in the yield of the product and significant reusability. Also, the antioxidant activities of the some of the newly synthesized compounds were carried out by 1,1‐diphenyl‐2‐picrylhydrazyl (PDDH) radical trapping and ferric ion reducing potential tests and compared with those of the synthetic antioxidants 2‐tert‐butylhydroquinone (TBHQ) and butylated hydroxytoluene (BHT). These compounds do not show good DPPH radical scavenging but display good ferric ion reducing power. 相似文献
458.
Maliheh Amiri Hossein Akbari Bashir Nedaee-shakarab Arash Boochani Amin Aminian Yousof Zangeneh Sirvan Naderi 《理论物理通讯》2019,71(4):455-462
The electronic and optical characteristics of the Sc2 CoSi Heusler with L21 structure and also the surface effect on electronic and optical properties, and the ?lms thermodynamic stability of the [001] direction in four cases including:Sc-Sc, Sc-Co, Sc-Si and Co-Si terminations are studied using the ?rst principles calculations(FPLAPW) within the framework of the density functional theory(DFT). The band structure calculations represent the ferromagnetic halfmetallic properties with 100% spin polarization and 0.54 e V indirect gap in spin down for Sc2 CoSi bulk with optimized lattice parameters of 6.25 A?. The total magnetic moment obtained for this compound is-1.0 μB, which is in accordance with Slater-Pauling rule. The half-metallic(HM) behavior by 100% spin polarization at Fermi level is occurred in the Sc-Si termination with a 0.32 eV gap in down spin. The optical responses have been calculated for the bulk and ScSi termination by a red shift in these parameters and the metallic treatments have been increased. According to the thermodynamic phase diagrams, it is shown the Sc-Si and Sc-Sc terminations are more stable than other terminations. 相似文献
459.
Protein properties and functions are strongly dependent on the structure and amino acid content. In this work, catalytic hydrogen evolution reaction (CHER) of five proteins (human serum albumin, lysozyme, β‐synuclein, H2 A and H3 histones) were studied using constant current chronopotentiometric stripping (CPS) with the aim to find out the association between protein content and its electrochemical response. We have shown that the height and potential of CPS peak H in dependence on accumulation potential differed for the studied proteins, while the CPS peak area was almost the same for all of them. CV and CPS peaks H of Cys‐containing proteins appeared at less negative potentials in comparison to proteins without Cys, suggesting easier CHER. Acidic and basic proteins not containing Cys can be also recognized due to their different CPS response after their adsorption at the positive and negative charged interface. 相似文献
460.
BSA‐Polysaccharide Interactions at Negatively Charged Electrode Surface. Effects of Current Density.
Constant current chronopotentiometric stripping (CPS) peak H due to catalytic hydrogen evolution reaction on Hg‐containing electrodes appeared useful in the analysis of protein complexes with single‐stranded and double‐stranded DNA as well as with peptides. In dependence on stripping current (Istr), structural transition of the protein alone or in complexes can be followed as a result of the protein exposure to electric field effects. For the first time we show here that the CPS analysis can be used for the study of the interaction of BSA with a polysaccharide namely sodium alginate (SA). BSA‐SA complex formation was accompanied by the shift of the structural transition of BSA to lower ‐Istr intensities. Another polysaccharide dextran did not alter Istr‐dependent structural transition of BSA. BSA‐SA complex can be disturbed by an electric field effect or high ionic strength confirming the electrostatic nature of BSA‐SA interaction. 相似文献