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1.
Although microRNAs (miRNAs) have been shown to be excellent indicators of disease state, current profiling platforms are insufficient for clinical translation. Here, we demonstrate a versatile hydrogel‐based microfluidic approach and novel amplification scheme for entirely on‐chip, sensitive, and highly specific miRNA detection without the risk of sequence bias. A simulation‐driven approach is used to engineer the hydrogel geometry and the gel‐reaction environment is chemically optimized for robust detection performance. The assay provides 22.6 fM sensitivity over a three log range, demonstrates multiplexing across at least four targets, and requires just 10.3 ng of total RNA input in a 2 hour and 15 minutes assay.  相似文献   
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The utilization of therapeutic plants is expanding around the globe, coupled with the tremendous expansion of alternative medicine and growing demand in health treatment. Plants are applied in pharmaceuticals to preserve and expand health—physically, mentally and as well as to treat particular health conditions and afflictions. There are more than 600 families of plants identified so far. Among the plants that are often studied for their health benefit include the genus of Salvia in the mint family, Lamiaceae. This review aims to determine the bioactive components of Salvia and their potential as antidiabetic agents. The search was conducted using three databases (PubMed, EMBASE and Scopus), and all relevant articles that are freely available in the English language were extracted within 10 years (2011–2021). Salvia spp. comprises many biologically active components that can be divided into monoterpenes, diterpenes, triterpenes, and phenolic components, but only a few of these have been studied in-depth for their health benefit claims. The most commonly studied bioactive component was salvianolic acids. Interestingly, S. miltiorrhiza is undoubtedly the most widely studied Salvia species in terms of its effectiveness as an antidiabetic agent. In conclusion, we hope that this review stimulates more studies on bioactive components from medicinal plants, not only on their potential as antidiabetic agents but also for other possible health benefits.  相似文献   
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The synthesis and characterization of a photocleavable block copolymer containing an ortho‐nitrobenzyl (ONB) linker between poly(methyl methacrylate) and poly(d ‐lactide) blocks is presented here. The block copolymers were synthesized via atom transfer radical polymerization (ATRP) of MMA followed by ring‐opening polymerization (ROP) of d ‐Lactide and ROP of d ‐lactide followed by ATRP of MMA from a difunctional photoresponsive ONB initiator, respectively. The challenges and limitations during synthesis of the photocleavable block copolymers using the difunctional photoresponsive ONB initiator are discussed. The photocleavage of the copolymers occurs under mild conditions by simple irradiation with 302 nm wavelength UV light (Relative intensity at 7.6 cm: 1500 μW/cm2) for several hours. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 4309–4316  相似文献   
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A new strategy that employs an exocyclic stereocenter to effect diastereocontrol in the tethered aminohydroxylation (TA) reaction is applied to the stereoselective synthesis of a range of amino alcohols in good to excellent yields, and with anti selectivities of up to 20:1. The influence of the reaction conditions and substrate parameters on the level of diastereocontrol is described. Furthermore, an “inside alkoxy” model is employed to rationalize the sense and degree of stereoselectivity observed in these systems.  相似文献   
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Benzimidazole (BMZ) is an organic nonlinear optical material, and it is possible to grow it in the laboratory by a slow evaporation solution growth technique using methanol as the solvent. Its nonlinear optical harmonic generation efficiency is 4.5 times higher than that of standard potassium dihydrogen phosphate (KDP) single crystal. It crystallizes with orthorhombic structure, which is noncentrosymmetric in nature, with lattice parameters a=13.58 Å, b=6.85 Å, c=6.97 Å. The functional groups of the grown specimen are confirmed by heteronuclear chemical shift correlation (HETCOR) analysis and it is found that other elements are not incorporated in the compound. The crystalline perfection is examined by high resolution X-ray diffraction (HRXRD), and its topographic image was recorded for the as-grown single crystal indicates the presence of some grain boundaries in the grown specimen. Thermal parameters such as thermal diffusivity (α), thermal conductivity (k), thermal effusivity (e), and heat capacity (c p ) have been determined by a photopyroelectric thermal wave method. In addition, piezoelectricity, birefringence, and third-order nonlinear optical properties have been examined. The two-photon absorption coefficient of the title compound is determined by the open-aperture Z-scan technique.  相似文献   
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In this paper we present an expression relating the lattice thermal expansion coefficient αL (10−6 K−1) for the AIIIBV and AIIBVI semiconductors with the product of ionic charges (Z1Z2), melting temperature (Tm) and nearest neighbor distance d (Å). The lattice thermal expansion coefficient of these compounds exhibit a linear relationship when plotted on a log–log scale against the melting temperature (Tm), but fall on different straight lines according to the ionic charge product of the compounds. A good agreement has been found between the experimental and calculated values of the lattice thermal expansion coefficient for AIIIBV and AIIBVI semiconductors.  相似文献   
10.
Rathi MS  Khanna PP  Mukherjee PK 《Talanta》1991,38(3):329-332
Lanthanum, cerium, neodymium, samarium, europium, gadolinium, dysprosium, erbium, ytterbium, lutetium and yttrium have been determined in 8 international rock standards by inductively coupled plasma atomic emission spectrometry (ICP-AES) without prior ion-exchange separation and preconcentration. The results for La, Ce, Nd, Eu, Dy, Yb and Y were in good agreement with the reported values, whereas those for Sm, Gd, Er and Lu were less accurate. However, the results for Sm, Gd, Er and Lu can also be used for studies of petrogenesis.  相似文献   
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