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91.
Stereographic (0001), (211 0) and (101 0) projections of α-Fe2O3 are presented in the form of both figures and tables. These can also be used for α-Al2O3, Cr2O3, Ti2O3 and V2O3, for which cases the maximum occurring deviations are indicated.  相似文献   
92.
93.
Macrophage polarization plays a crucial role in inflammatory processes. The histone deacetylase 3 (HDAC3) has a deacetylase-independent function that can activate pro-inflammatory gene expression in lipopolysaccharide-stimulated M1-like macrophages and cannot be blocked by traditional small-molecule HDAC3 inhibitors. Here we employed the proteolysis targeting chimera (PROTAC) technology to target the deacetylase-independent function of HDAC3. We developed a potent and selective HDAC3-directed PROTAC, P7 , which induces nearly complete HDAC3 degradation at low micromolar concentrations in both THP-1 cells and human primary macrophages. P7 increases the anti-inflammatory cytokine secretion in THP-1-derived M1-like macrophages. Importantly, P7 decreases the secretion of pro-inflammatory cytokines in M1-like macrophages derived from human primary macrophages. This can be explained by the observed inhibition of macrophage polarization from M0-like into M1-like macrophage. In conclusion, we demonstrate that the HDAC3-directed PROTAC P7 has anti-inflammatory activity and blocks macrophage polarization, demonstrating that this molecular mechanism can be targeted with small molecule therapeutics.  相似文献   
94.
Structural flexibility plays a crucial role in protein function. To assess whether specific structural changes are associated with the binding of an immunoreceptor tyrosine-based activation motif (ITAM) to the tandem Src homology-2 domains (tSH2) of the spleen tyrosine kinase [EC 2.7.7.112] (Syk), we used an approach based on protein hydrogen/deuterium exchange in the presence and absence of the diphosphorylated ITAM peptide. The protein deuterium uptake by the intact Syk protein was monitored in time by electrospray mass spectrometry, which revealed a dramatic relative decrease in deuterium uptake when the protein was bound to the ITAM peptide, suggesting an overall change in protein dynamics. Subsequently, the deuterium incorporation of individual segments of the protein was investigated using proteolysis and matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) peptide mass-analysis, which revealed that several regions of Syk tSH2 are significantly more protected from exchange in the presence of the ITAM peptide. Four protected regions encompass the phosphotyrosine and hydrophobic binding sites on the SH2 domains, whereas two other protected regions are located in the inter-SH2 linker motif and do not make any direct contacts with the peptide. Interestingly, our data suggest that binding of the ITAM peptide to Syk tSH2 induces distal structural effects on the protein that stabilize the inter-SH2 linker region, possibly by raising the degree of helical structure upon binding.  相似文献   
95.
Meaningful learning of formal mathematics in regular classrooms remains a problem in mathematics education. Research shows that instructional approaches in which students work collaboratively on tasks that are tailored to problem solving and reflection can improve students’ learning in experimental classrooms. However, these sequences involve often carefully constructed reinvention route, which do not fit the needs of teachers and students working from conventional curriculum materials. To help to narrow this gap, we developed an intervention—‘shift problem lessons’. The aim of this article is to discuss the design of shift problems and to analyze learning processes occurring when students are working on the tasks. Specifically, we discuss three paradigmatic episodes based on data from a teaching experiment in geometrical proof. The episodes show that is possible to create a micro-learning ecology where regular students are seriously involved in mathematical discussions, ground their mathematical understanding and strengthen their relational framework.  相似文献   
96.
The effects of soybean and castorbean meals were evaluated separately, and in combinations at different ratios, as substrates for lipase production by Botryosphaeria ribis EC-01 in submerged fermentation using only distilled water. The addition of glycerol analytical grade (AG) and glycerol crude (CG) to soybean and castorbean meals separately and in combination, were also examined for lipase production. Glycerol-AG increased enzyme production, whereas glycerol-CG decreased it. A 24 factorial design was developed to determine the best concentrations of soybean meal, castorbean meal, glycerol-AG, and KH2PO4 to optimize lipase production by B. ribis EC-01. Soybean meal and glycerol-AG had a significant effect on lipase production, whereas castorbean meal did not. A second treatment (22 factorial design central composite) was developed, and optimal lipase production (4,820 U/g of dry solids content (ds)) was obtained when B. ribis EC-01 was grown on 0.5 % (w/v) soybean meal and 5.2 % (v/v) glycerol in distilled water, which was in agreement with the predicted value (4,892 U/g ds) calculated by the model. The unitary cost of lipase production determined under the optimized conditions developed ranged from US$0.42 to 0.44 based on nutrient costs. The fungal lipase was immobilized onto Celite and showed high thermal stability and was used for transesterification of soybean oil in methanol (1:3) resulting in 36 % of fatty acyl alkyl ester content. The apparent K m and V max were determined and were 1.86 mM and 14.29 μmol min?1 mg?1, respectively.  相似文献   
97.
98.
The 13C NMR spectra of a series of 3-allyl-, 3-prenyl- and 3-benzyl-phlorophenone compounds are reported. Relative substituent effects are discussed.  相似文献   
99.
Residual Reynolds number effects in the established data for the velocity profile in turbulent boundary layers (and in pipe or channel flows) are found to be remarkably large. We combine two eddy-viscosity models (with overlapping validity in the inertial sublayer) and show (both analytically and numerically) that this enhancement (which involves a viscous correlation length) arises from inner-outer sublayer interaction.  相似文献   
100.
H. Dekker 《Physica A》1980,103(3):586-596
The Onsager-Machlup Lagrangian for diffusion processes in curved spaces is determined by evaluating the covariant path integral by means of a spectral analysis of smooth trajectories in Riemannian normal coordinates. The Lagrangian involves a novel curvature scalar potential term v=?(18)R. The present treatment replaces an earlier one.  相似文献   
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