Enantioselective assembly of multi-layer 3D chirality

The first enantioselective assembly of sandwich-shaped organo molecules has been achieved by conducting dual asymmetric Suzuki-Miyaura couplings and nine other reactions. This work also presents the first fully C-C anchored multi-layer 3D chirality with optically pure enantiomers. As confirmed by X-ray diffraction analysis that this chiral framework is featured by a unique C₂-symmetry in which a nearly parallel fashion consisting of three layers: top, middle and bottom aromatic rings. Unlike the documented planar or axial chirality, the present chirality shows its top and bottom layers restrict each other from free rotation, i.e., this multi-layer 3D chirality would not exist if either top or bottom layer is removed. Nearly all multi-layered compounds showed strong luminescence of different colors under UV irradiation, and several randomly selected samples displayed aggregation-induced emission (AIE) properties. This work is believed to have broad impacts on chemical, medicinal and material sciences including optoelectronic materials in future.     

基于自清洁理念的下水道中沉积物运移的设计标准

研究目的：通过比较沉积物运移的不同标准,经选优得出更高精度的标准。创新要点：使用更少的参数和分情况来获得高精度的设计标准。研究方法：1.按状态将下水道中沉积物分成两类：没有沉淀的沉积物和沉淀的推移质;2.利用已有设计标准的方程,运用非线性回归和 MINITAB软件,得到不同情况下的最佳方程式;3.用实验所得的值对各方程预测值进行验证,比较各方程式的预测精度。 重要结论：1.本文提出的方程式可以预测不同情况下的沉积物运移;2.相比于其它标准,本文提出的方程式形式简单、所需参数少和参数估计简单,并且预测精度更高。     

Development and validation of a measuring instrument for digital library maturity

Development of a digital library demands extensive financial, human, and technological investments. Appropriate models and measurement tools are required to achieve the goals of these libraries to assess them. This research was conducted with the aim of developing and validating a tool to measure the maturity of a digital library based on the “digital library maturity model” (DLMM). Two sources including literature and experts' opinion were used to determine the criteria for each code. Expert opinion and confirmatory factor analysis were used to confirm the content and construct validity of the developed tool, respectively. The reliability of the designed tool was examined by the Cronbach's alpha test. Finally, the designed tool validity and reliability were confirmed. Managers of digital libraries can use this tool to understand the maturity level of their digital libraries and plan to improve the library or to attain advanced levels of maturity.     

An Integrated Holistic Method for Teaching Introductory German to Community College Students

The study reported in this paper investigated the effectiveness of an Integrated Holistic Teaching Method for teaching grammatical structure, cultural norms and behavior, writing and listening to German language students. The study involved a sample of 24 undergraduate students enrolled in an introductory college-level German course at a large urban community college in Texas. The research utilized a pre- and posttest design to study the instructional effectiveness of the Integrated Holistic Teaching Method. The higher posttest mean scores indicated significant improvement in student learning in the 4 major language skills areas as an artifact of involvement in the Integrated Holistic Teaching Method.     

Aqueous biphasic microprinting approach to tissue engineering

We summarize a recently developed microtechnology for printing biomaterials on biological surfaces. The technique is based on the use of immiscible aqueous solutions of two biopolymers and allows spatially defined placement of cells and biomolecules suspended in the denser aqueous phase on existing cell layers and extracellular matrix hydrogel surfaces maintained in the second phase. Printing takes place due to an extremely small interfacial tension and density difference between the two aqueous phases. The contact-free printing process ensures that both printed cells and the underlying cell monolayer maintain full viability and functionality. The technique accommodates both arbitrarily shaped patterns and microarrays of cells and bioreagents. The capability to print cells and small molecules on existing cell layers enables unique interrogations of the effects of cell-cell and cell-material interaction on cell fate and function. Furthermore, the very gentle conditions and the ability to directly pattern nongel embedded cells over cells make this technology appealing to tissue engineering applications where patterned multicellar organization with minimal scaffolding materials is needed, such as in dense tissues of the skeletal muscle and liver.     

‘Brown Morning:’ classed interpretations of anti-racist text

This article examines the interpretations of high school students from different socioeconomic locations (in terms of socioeconomic class and ethnicity) with regard to the text Brown Morning, used as a didactic tool for antiracism education within the framework of Civics courses. The research findings uncover differences in the students’ interpretations of the text. An in-depth understanding of these differences will be attained through clinical analyses based on the distinctions between metaphor and metonymy made by linguist Roman Jakobson. Among students from low socioeconomic locations, interpretations related to racism were dominated by metonymic characteristics, while that of students from higher socioeconomic locations were predominantly metaphoric. Study findings do not only show the different interpretations among the students, but also the various ways in which metaphorical and metonymic language affect teachers. These analyses will focus on the reasons for these differences and their implications regarding the links between social locations, language, and education.     

A new direct method based on the Chebyshev cardinal functions for variable-order fractional optimal control problems

In this paper, a new direct method based on the Chebyshev cardinal functions is proposed to solve a class of variable-order fractional optimal control problems (V-OFOCPs). To this end, a new operational matrix (OM) of variable-order (V-O) fractional derivative in the Caputo sense is derived for these basis functions and is used to obtain an approximate solution for the problem under study. In the proposed method, the state and the control variables are expanded in terms of the Chebyshev cardinal functions with unknown coefficients, at first. Then, the OM of V-O fractional derivative and some properties of the Chebyshev cardinal functions are employed to achieve a nonlinear algebraic equation corresponding to the performance index and a nonlinear system of algebraic equations corresponding to the dynamical system in terms of the unknown coefficients. Finally, the method of constrained extremum is applied, which consists of adjoining the constraint equations derived from the given dynamical system and the initial conditions to the performance index by a set of undetermined Lagrange multipliers. As a result, the necessary conditions of optimality are derived as a system of algebraic equations in the unknown coefficients of the state variable, control variable, and Lagrange multipliers. Furthermore, some numerical examples of different types are demonstrated with their approximate solutions for confirming the high accuracy and applicability of the proposed method.     

Soluble Tumor Necrosis Factor Like Weak Inducer of Apoptosis and Vitamin D in Hemodialysis Patients: Relation to Carotid Intima-Media Thickness

Cardiovascular disease, as the leading cause of patient death with chronic kidney disease, could be predicted by carotid atherosclerosis. The aim of the present study was to evaluate a possible relationship between serum soluble tumor necrosis factor-like weak inducer of apoptosis (sTWEAK) and Vitamin D levels with mean right/left carotid intima-media thickness (cIMT), in the hemodialysis (HD) patients. In this cross-sectional study, serums were obtained from 50 stable chronic HD patients and 39 healthy controls. The serum levels of sTWEAK, Vitamin D, intact parathyroid hormone (iPTH) in both groups, and cIMT were determined in HD patients by standard methods. Serum levels of sTWEAK were higher [808.8 (521.6–5032.4) pg/ml vs. 664.4 (487.4–2955.8) pg/ml (p = 0.006)] and Vitamin D levels were lower [13.4 (2.5–153) ng/ml vs. 27.8 (18.4–59.0) ng/ml (p = 0.001)] in the hemodialysis patients than in the healthy control. No important correlation was found between sTWEAK Vitamin D levels (r = 0.010/p = 0.946), and mean right(r = ?0.194/p = 0.178) and left (r = 0.061/p = 0.673) cIMT in the HD patients. Our study shows that sTWEAK levels are elevated in HD patients. This elevation has no association with the cIMT.