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Substituent effects at the C2-, C8-, and N-positions of adenine and purine on the structural and π-electronic changes in their four tautomers were studied using the B97D3/aug-cc-pvdz computational level. The effect of various substituents (NO2, CN, CHO, Cl, F, H, Me, OMe, OH, and NH2) was characterized by the charge of the substituent active region (cSAR) approach and Hammett substituent constants σ. It has been found that for both adenine and purine derivatives, substituents from the C8-X position have a stronger influence on their electronic structure than from the C2-X and N-X positions. The presence of the amino group in adenine enhances the substituent effect compared to that which occurs in purine. In addition, its electronic structure is more sensitive to the effect of the substituent in 3H and 1H than in the 9H and 7H adenine tautomers. For a given substituent, a large variation in cSAR(X) values is observed, strongly dependent on the substitution position. For 7H and 9H adenine tautomers for C8-X systems, substituents reduce the aromaticity of the five-membered rings but increase the aromaticity of the six-membered rings.Multiherbal preparation of Coptidis rhizoma, Scutellariae radix, and Rhei rhizoma is a well-known herbal formula, which is widely used in the prescription for relieving heat toxicity, inflammation of the intestine, and eczema. However, little is known about the characteristics of the physical and chemical qualities of industrial pharmaceutical products. The aim of the study is to develop a liquid chromatography system to examine the quality and quantity of pharmaceutical products. Besides scanning electron microscopy, light microscopy photographs with Congo red staining and iodine-KI staining were used for physical examination of the quality of the pharmaceutical products. A reverse-phase C18 column was used to separate the analytes of baicalin, berberine, rhein, and p-hydroxybenzoate (internal standard) with a gradient eluent mobile phase of acetonitrile and 10 mM NaH2PO4 (pH 3.0, adjusted by orthophosphoric acid). The results demonstrated that a large variety of content range presents among the testing herbal pharmaceutical products. The contents of rhein, baicalin, and berberine were around 0.22-22.46, 0.44-50.79, and 0.41-2.48 mg/g, respectively. The physical examination data demonstrated that different brands of industrial pharmaceutical products have different shapes of granules or rods. In summary, to ensure the clinical efficacy of complicated herbal medicine, both quality and quantity controls are all very important. This study provides a reference standard operating procedure guide for the quality control (QC) with chemical and physical examination for the Chinese herbal pharmaceutical products of San-Huang-Xie-Xin-Tang (SHXXT).NS3/4A protease of hepatitis C virus (HCV) plays an important role in viral RNA replication. A 1,4-diphenylbutanedicarboxylic acid derivative, namely, phyllanthin, extracted from the leaf of a herbal plant, Phyllanthus amarus, inhibits HCV NS3/4A protease and replication activities. However, the reduced aqueous solubility, high toxicity, and poor oral bioavailability are major impediments with phyllanthin. We herein present a design approach to generate phyllanthin congeners in order to potentiate inhibition activity against protease. The phyllanthin congeners were synthesized by chemical methods and subjected to systematic biological studies. One of the congeners, annotated as D8, is identified as a novel and potent inhibitor of the HCV-NS3/4Aprotease activity in vitro and the viral RNA replication in cell culture. Structural analysis using the computational-based docking approach demonstrated important noncovalent interactions between D8 and the catalytic residues of the viral protease. Furthermore, D8 was found to be significantly nontoxic in cell culture. More importantly, oral administration of D8 in BALB/c mice proved its better tolerability and bioavailability, as compared to native phyllanthin. Taken together, this study reveals a promising candidate for developing anti-HCV therapeutics to control HCV-induced liver diseases.Despite having great value across a wide variety of scientific fields, two-photon polymerizations currently suffer from two significant problems the need for photoinitiators, which generate toxic side products, and the irreversibility of the process. Hence, the design of a versatile approach that circumvents these issues represents a major scientific challenge. Herein, we report a two-photon absorption strategy where reversible [2 + 2] cycloaddition of bis-thymines was achieved without the need for any photoinitiator. The cycloaddition and cycloreversion reactions could be induced by simply changing the irradiation wavelength, and repeated writing and erasing cycles were performed. The simplicity, reversibility, and biocompatibility of this strategy open up a whole new toolbox for applications across a wide variety of scientific fields.The effect of elicitation in butterhead lettuce on carotenoid and polyphenol metabolism was evaluated. Different concentrations of arachidonic acid (AA), salicylic acid (SA), methyl jasmonate (MJ) (15, 45, and 90 μM) and Harpin protein (HP) (30, 60, and 120 mg/L) were applied on red and green butterhead lettuces. Total phenolic and flavonoid content were incremented by MJ (90 μM) in green and red lettuce. Carotenoids were increased in red lettuce (AA; 45 μM). Green lettuce modifies their phenolic acid profile after elicitation with AA and MJ; meanwhile, red lettuce incremented mainly in hydroxycinnamic acids and flavonols, MJ being the elicitor with the highest effect. There was an impact on secondary metabolite enzyme gene transcript concentration. Phenylalanine ammonia-lyase (PAL) and lycopene beta cyclase (LBC) increased in both varieties after elicitation. MDL28170 A relationship between phytochemical increase and the activation of the metabolic pathways after elicitation in butterhead lettuce was observed.A quaternary ammonium and titanium codoped phosphotungstate (QA0.5Ti0.5H0.5PW) catalyst was prepared by the ion exchange method and used as a solid acid catalyst for the synthesis of n-butyl oleate. The catalyst was characterized by Fourier transform infrared, elemental analyzer, energy-dispersive X-ray spectrometry, Brunauer-Emmett-Teller, scanning electron microscopy, and Hammett indicator methods. QA0.5Ti0.5H0.5PW showed a higher catalytic activity than other phosphotungstate solid acid catalysts reported by literature, and the esterification rate reached 99% under optimized conditions. Moreover, QA0.5Ti0.5H0.5PW exhibited well reusability. An esterification rate of 90.1% was still obtained in the eighth run.This paper describes a simple, reproducible, and scalable procedure for the preparation of a SiO2-containing supercapacitor with high cycle stability. A carbon mesoporous material (CMM) with a high specific surface area, CMK-3, was adopted as an electric double-layer capacitor (EDLC) active material for the preparation of electrodes for the supercapacitor. The optimized SiO2 content decreased as the microsphere diameter decreased, and the optimal specific capacitance was obtained with 6 wt % SiO2 microspheres (100 nm size). The capacitance improved from 133 to 298 F/g. The corresponding capacitance retention rate after 1000 cycles increased from 68.04 to 91.53%. In addition, the energy density increased from 21.05 to 26.25 Wh/kg with a current density of 1 A/g. Finally, similar results based on active carbon, CeO2/CMK-3, and graphene/CNT/MnOv composite electrodes demonstrated that the proposed method exhibits wide compatibility with diverse electrode materials.The biofouling of marine organisms on a surface induces serious economic damage. One of the conventional anti-biofouling strategies is the use of toxic chemicals. In this study, a new eco-friendly oleamide-PDMS copolymer (OPC) is proposed for sustainable anti-biofouling and effective drag reduction. The anti-biofouling characteristics of the OPC are investigated using algal spores and mussels. The proposed OPC is found to inhibit the adhesion of algal spores and mussels. The slippery features of the fabricated OPC surfaces are examined by direct measurement of pressure drops in channel flows. The proposed OPC surface would be utilized in various industrial applications including marine vehicles and biomedical devices.In this paper, authors propose a study on microwave gas sensors and the influence of critical key parameters such as the sensitive material and the circuit conception process. This work aims to determine the influence of these parameters on the quality of the final response of the microwave gas sensor. The fixed geometry of the sensor is a microstrip interdigital capacitor coated with a sensitive layer excited with two 50 Ω SMA ports. The sensitive material has been chosen in order to interact with the target gas ammonia. Indeed, this gas interacts with phthalocyanine and metal oxides like hematite, TiO2. To explore the effect of the circuit manufacturing process, three series of samples are prepared. The first series of sensors is produced by classical UV photolithography (process) in the laboratory. The second series of sensors is produced by a subcontractor specialized in rf circuits. The third series is obtained by the experimental platform of the FEMTO-ST laboratory with EVG620 Automated Mask Alignment System Nanoimprint lithography in a clean room. To examine the reliability of this gas sensor at room temperature, it was exposed to different ammonia gas concentrations from 100 to 500 ppm in an argon flow to eliminate coadsorption phenomena. According to the recorded frequency responses, the reflection and transmission coefficients show a change of resonance amplitude due to electrical characteristic modification. This can be correlated to the presence of gaseous ammonia. The chemical nature of the sensitive material layer has a major influence at the excited frequency range. The process of conception influences the sensor sensitivity. The analysis of the results shows a strong correlation between the injected ammonia concentration and its frequency response. The influence of the critical key parameters cited is discussed here.The purpose of this attempt is to present a new investigation approach to achieve the in situ observation of the microscopic structure and morphology of wax crystals under quiescent and shear conditions. The rheo-microscopy simultaneous measurement system of a rheometer is employed to ensure in situ observation. A multi-angle composite light source is created to obtain a high-quality image. It is demonstrated that the new approach can achieve a better identification and distinction of wax crystals, as well as the outstanding wax boundary delineation. Based on this, some new findings related to the microscopic structure and morphology of wax crystals are elaborated. Additionally, the in situ observations of wax crystals under dynamic cooling at different shear rates are performed. It is noticed from the obtained results that wax crystals and their aggregates exhibit significant stereoscopic structural characters, because of growth of wax crystals and their overlap in 3-D space. Shear can change the morphology of single wax crystals, but hardly destroy the structure or growth.