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101.
Beliefs influencing students’ mathematical learning and problem solving are structured and intertwined with larger affective and cognitive structures. This theoretical article explores a psychological concept we term an engagement structure, with which beliefs are intertwined. Engagement structures are idealized, hypothetical constructs, analogous in many ways to cognitive structures. They describe complex “in the moment” affective and social interactions as students work on conceptually challenging mathematics. We present engagement structures in a self-contained way, paying special attention to their theoretical justification and relation to other constructs. We suggest how beliefs are characteristically woven into their fabric and influence their activation. The research is based on continuing studies of middle school students in inner-city classrooms in the USA. 相似文献
102.
Generalizing the quantifiers used to classify correlations in bipartite systems, we define genuine total, quantum, and classical correlations in multipartite systems. The measure we give is based on the use of relative entropy to quantify the distance between two density matrices. Moreover, we show that, for pure states of three qubits, both quantum and classical bipartite correlations obey a ladder ordering law fixed by two-body mutual informations, or, equivalently, by one-qubit entropies. 相似文献
103.
Solvability of the Dirichlet Problem in W~(2,p )for a Class of Elliptic Equations with Singular Data
Loredana CASO 《数学学报(英文版)》2014,30(5):737-746
We prove an existence and uniqueness result for the Dirichlet problem for a class of elliptic equations with singular data in weighted Sobolev spaces. 相似文献
104.
105.
Wolfgang Bermel Dr. Ivano Bertini Prof. Isabella C. Felli Prof. Riccardo Peruzzini Roberta Pierattelli Prof. 《Chemphyschem》2010,11(3):689-695
Provided that 13C‐detected NMR experiments are either preferable or complementary to 1H detection, we report here tools to determine Cα? C′, C′? N, and Cα? Hα residual dipolar couplings on the basis of the CON experiment. The coupling constants determined on ubiquitin are consistent with the subset measured with the 1H‐detected HNCO sequences. Since the utilization of residual dipolar couplings may depend on the mobility of the involved nuclei, we also provide tools to measure longitudinal and transverse relaxation rates of N and C′. This new set of experiments is a further development of a whole strategy based on 13C direct‐detection NMR spectroscopy for the study of biological macromolecules. 相似文献
106.
Roberta Cavalli Emilio Marengo Otto Caputo Elena Ugazio Maria Rosa Gasco 《Journal of Dispersion Science and Technology》2013,34(7):717-734
The influence of twenty five different alcohols on the formation of warm oil-in-water (O/W) microemulsions was investigated. Selected concentrations of each alcohol were added to fixed amounts of stearic acid, Tween 20 and water at 65 ° C. Fifteen alcohols formed microemulsions, at least at one of the concentrations. A pattern recognition study was performed to elucidate the activities of the alcohols by Principal Component Analysis (PCA). Linear Discriminant Analysis (LDA) was used to classify them. Two classification functions, obtained for alcohols forming / not forming microemulsions, suggest that the formation of warm O/W microemulsion is linked to the nature and the dimension/lipophilicity of the alcohol. 相似文献
107.
Existence and non-existence results are established for quasilinear elliptic problems with nonlinear boundary conditions and lack of compactness. The proofs combine variational methods with the geometrical feature, due to the competition between the different growths of the nonlinearities. 相似文献
108.
109.
Silvana Casati Ada Manzocchi Roberta Ottria Pierangela Ciuffreda 《Magnetic resonance in chemistry : MRC》2010,48(9):745-748
The complete 1H, 13C and 15N NMR signals assignments of some new isopentenyladenosine analogues were achieved using one‐ and two‐dimensional experiments (gs‐NOESY, gs‐HMQC and gs‐HMBC). Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
110.
Roberta Ottria Silvana Casati Pierangela Ciuffreda 《Magnetic resonance in chemistry : MRC》2012,50(12):823-828
The complete 1H, 13C and 15N NMR signal assignments of some N‐ and O‐acylethanolamines, important family of naturally occurring bioactive lipid mediators, were achieved using one‐dimensional and two‐dimensional experiments (gs‐HMQC and gs‐HMBC). Copyright © 2012 John Wiley & Sons, Ltd. 相似文献