Three aromatic amino acids in gastric juice as potential biomarkers for gastric malignancies

For screening early-stage gastric malignancies, the existing serum biomarkers have limited sensitivity and specificity. Gastric juice biomarkers are scarce and require further investigation. We divided this study on searching potential biomarkers into four parts: (1) detection of differential fluorescence spectrum and peaks in the gastric juice from patients using fluorescence spectroscopy and HPLC, (2) identification and validation of differential peaks using LC/MS and NMR, (3) quantification of potential biomarkers, and (4) establishment of diagnostic detection. The fluorescence intensity (FI), tyrosine, phenylalanine, tryptophan and total protein content were significantly higher in the gastric juice of patients with gastric malignancies (all P<0.01). With all P<0.001, the areas under the receiver operating characteristic curves of the biomarkers were tyrosine, 0.838; phenylalanine, 0.856; and tryptophan, 0.816. At a specificity of 79.4%, the sensitivity for gastric malignancy detection with phenylalanine was 87.9% only. Aromatic amino acids in gastric juices could be used as potential diagnostic biomarkers to screen gastric malignancies. It is a less-invasive and economical method compared to gastric biopsy.     

A hybrid descent method for solving a convex constrained optimization problem with applications

The purpose of this paper is to introduce a hybrid descent algorithm for finding a common point in fixed‐point sets of quasi‐nonexpansive mappings and solution sets of variational inequality problems. In the framework of Hilbert spaces, the strong convergence of the hybrid descent algorithm is established. Numerical experiments for the bandwidth allocation, which demonstrate the effectiveness, performance, and convergence of the proposed algorithm, are provided.     

一类粗糙奇异积分的加权Triebel-Lizorkin有界性

本文研究了一类粗糙奇异积分算子的加权Triebel-Lizorkin有界性.对核函数Ω∈Llog L(Sn-1)建立了径向权函数的加权有界性;而对于核函数Ω∈Lr(Sn-1),1相似文献   

Total synthesis of (−)-elegansidiol by using an abnormal Beckmann fragmentation of Hajos ketone oxime as a key step

Abnormal Beckmann fragmentation of Hajos ketone oxime regioselectively forms of a chiral 1-oxygenated 2,2-dimethyl-4-methylene-cyclohexan skeleton. Using this transformation as a key step, the total synthesis of (−)-elegansidiol, an oxygenated mono-carbocyclic sesquiterpenoid, was achieved.     

KGd(MoO4)2:Eu as a promising red phosphor for light-emitting diode application

A red phosphor KGd(MoO₄)₂:Eu³⁺ was prepared by solid-state reaction technique at high temperature. Its photoluminescent property was investigated and the optimum concentration of Eu³⁺ doped in the KGd(MoO₄)₂ is 25 mol%. Compared with Y₂O₂S:0.05Eu³⁺, the obtained KGd(MoO₄)₂:Eu³⁺ shows wider excitation band around 400 nm, higher intensity of Eu^{3+ 5}D₀–⁷F₂ emission upon excitation 393 nm, and the CIE chromaticity coordinates (x = 0.655, y = 0.345) are closer to the standard of National Television Standard Committee (NTSC). The optical properties of KGd(MoO₄)₂:Eu³⁺ suggest that it is an efficient red-emitting phosphor for light-emitting diode applications.     

A (2+ϵ)-approximation for precedence constrained single machine scheduling with release dates and total weighted completion time objective

We give a $(2+?)$-approximation algorithm for minimizing total weighted completion time on a single machine under release time and precedence constraints. This settles a recent conjecture on the approximability of this scheduling problem (Skutella, 2016).     

Analyses of gibberellins in coconut (Cocos nucifera L.) water by partial filling-micellar electrokinetic chromatography-mass spectrometry with reversal of electroosmotic flow

In this paper, we present the results of simultaneous screening of eight gibberellins (GAs) in coconut (Cocos nucifera L.) water by MEKC directly coupled to ESI-MS detection. During the development of MEKC-MS, partial filling (PF) was used to prevent the micelles from reaching the mass spectrometer as this is detrimental to the MS signal, and a cationic surfactant, cetyltrimethylammonium hydroxide, was added to the electrolyte to reverse the EOF. On the basis of the resolution of the neighboring peaks, different parameters (i.e., the pH and concentration of buffer, surfactant concentrations, length of the injected micellar plug, organic modifier, and applied separation voltage) were optimized to achieve a satisfactory PF-MEKC separation of eight GA standards. Under optimum conditions, a baseline separation of GA standards, including GA1, GA3, GA5, GA6, GA7, GA9, GA12, and GA13, was accomplished within 25 min. Satisfactory results were obtained in terms of precision (RSD of migration time below 0.9%), sensitivity (LODs in the range of 0.8-1.9 microM) and linearity (R2 between 0.981 and 0.997). MS/MS with multiple reaction monitoring (MRM) detection was carried out to obtain sufficient selectivity. PF-MEKC-MS/MS allowed the direct identification and confirmation of the GAs presented in coconut water (CW) sample after SPE, while, the quantitative analysis of GAs was performed by PF-MEKC-MS approach. GA1 and GA3 were successfully detected and quantified in CW. It is anticipated that the current PF-MEKC-MS method can be applicable to analyze GAs in a wide range of biological samples.     

Efflorescence relative humidity of mixed sodium chloride and sodium sulfate particles

We study the efflorescence relative humidity (ERH) of particles composed of sodium chloride and sodium sulfate. Both experimental and theoretical investigations are conducted to explore the effects of particle size and mixing ratios between two inorganic materials on ERH. A previously developed theoretical model (Gao et al. J. Phys. Chem. A 2006, 110, 7602; ref 1) is applied as the framework to build a formulation assuming that one salt nucleates much faster than the other, and the critical nuclei formation of the former controls the rate of efflorescence. The predicted ERHs agree favorably with the experimental data, except for particles containing Na2SO4 in a mole fraction of around 0.25. At this composition, our model underestimates the ERH, indicating certain factors involved in the efflorescent processes that are overlooked in our formulation. Relative to particles larger than 40 nm, the Kelvin effect more significantly affects particles smaller than this size.     

Weighted quasi-equilibrium problems with lower and upper bounds

This paper is devoted to studying the solution existence of weighted quasi-equilibrium problems with lower and upper bounds by using maximal element theorems, a fixed point theorem of set-valued mappings and Fan–KKM theorem, respectively. Some new results are obtained.