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  • Author or Editor: Feng Qi x
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In the paper, the authors introduce a new concept of geometrically r-convex functions and establish some inequalities of Hermite-Hadamard type for this class of functions.

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Abstract  

The psi function ψ(x) is defined by ψ(x) = Γ′(x)/Γ(x) and ψ (i)(x), for i ∈ ℕ, denote the polygamma functions, where Γ(x) is the gamma function. In this paper, we prove that the functions

\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$[\psi '(x)]^2 + \psi ''(x) - \frac{{x^2 + 12}} {{12x^4 (x + 1)^2 }}$$ \end{document}
and
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$\frac{{x + 12}} {{12x^4 (x + 1)}} - \{ [\psi '(x)]^2 + \psi ''(x)\}$$ \end{document}
are completely monotonic on (0,∞).

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Abstract

For a long time, rankings overused in evaluating Chinese universities’ research performance. The relationship between research production and research quality hasn't been taken seriously in ranking systems. Most university rankings in China put more weight on research production rather than research quality. Recently, the developmental strategy of Chinese universities has shifted from ‘quantity’ to ‘quality’. As a result, a two-dimensional approach was developed in this article to balance ‘quantity’ and ‘quality’. The research production index and the research quality index were produced to locate research universities (RU) from Mainland China, Hong Kong (HK) and Taiwan (TW) in the two-dimensional graph. Fifty-nine RU were classified into three categories according to their locations, which indicated the relevant level of research performance. University of Hong Kong, National Taiwan University, Tsing Hua University and Peking University appeared to be leading universities in research performance. The result showed that the mainland universities were generally of higher research production and lower research quality than HK and TW universities, and proved that the merging tides of Chinese universities enlarged their research production while causing a low level of research quality as well.

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Abstract  

To increase the tumor uptake of Val-Gly-Gly (VGG), adenine was introduced into the peptide. N-mercaptoacetyl-VGG-adenine (MAVGG-adenine) and MAVGG were labeled with 99mTc using a solution of SnCl2 and tartaric acid as reducing agent. Biodistribution in mice bearing the S180 tumor was measured and γ imaging was performed. Compared with MAVGG, adenine conjugated MAVGG had higher tumor uptake and tumor to normal tissue ratios, which suggested that the tumor uptake property of a peptide may be improved by introducing a nucleotide base. The high contrasted tumor images of 99mTc-MAVGG-adenine also suggested its potential utility as tumor imaging agent.

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Abstract  

Two peptide ligands conjugated adenine, [9-N-(tritylmercapto acetyl diglycyl aminoethyl) adenine, Tr-MAG2-Ade] and [9-N-(tritylmercapto acetyl triglycyl aminoethyl) adenine, Tr-MAG3-Ade], are synthesized and labeled with 99mTc by directly labeling method. The stability of 99mTc-MAG2-adenine and 99mTc-MAG3-adenine in vitro is measured. The uptake radios of tumor to muscle at 3h post-injection are 5.70 and 4.92, respectively. The biodistribution and scintigraphic imaging studies show that the two complexes have high localization in tumor and high contrasted tumor images can be obtained, which suggest their potential utility as tumor imaging agents. But the high radioactivity of abdomen could prevent the tumor imaging in this area.

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The leaves of Hibiscus sabdariffa L. are one of the sources of food and traditional medicine. A combination of high-performance thin-layer chromatography (HPTLC) bioautographic assay with mass spectrometry (MS) has been performed to screen and identify the antioxidant compounds in the leaves of H. sabdariffa L. The crude extract of H. sabdariffa L. was separated on silica gel 60 HPTLC plates in an automatic developing chamber (ADC2) with toluene–ethyl acetate–formic acid–methanol (6:6:1.6:1, v/v) as the mobile phase. Antioxidant bands were visualized by dipping in 2,2-diphenyl-1-picrylhydrazyl (DPPH) reagent. Five antioxidant compounds were identified as neochlorogenic acid (1), chlorogenic acid (2), cryptochlorogenic acid (3), rutin (4), and isoquercitrin (5), which could be the predominant contributors to the antioxidant activity of the leaves of H. sabdariffa L. Furthermore, principal component analysis (PCA) was carried out to discriminate ten accessions of H. sabdariffa L. using an image-processing software. This simple HPTLC fingerprint assisted by PCA can be used as a reliable method for the discrimination of different accessions of H. sabdariffa L.

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