Yusufmeyers6533
Toxicity studies are necessary for the development of a new drug. Naphthalene is a bicyclic molecule and is easy to derivatize. In our previous study, a derivative of naphthalene (4-phenyl,3,4-dihydrobenzoquinoline-2(H)one) was synthesized and reported its in vitro activity on different enzymes. This study was a probe to investigate the toxicity potential of that compound (SF3). Acute oral (425), subacute (407), and teratogenicity (414) studies were planned according to their respective guidelines given by organization of economic cooperation and development (OECD). Acute oral, subacute, and teratogenicity studies were carried out on 2000, 5-40, and 40 mg/kg doses. Blood samples were collected for hematological and biochemical analyses. Vital organs were excised for oxidative stress (superoxide dismutase, catalase, glutathione, and malondialdehyde) and histopathological analysis. LD 50 of SF3 was higher than 2000 mg/kg. In acute and subacute studies, levels of alkaline phosphates and aspartate transaminase were increased. Teratogenicity showed no resorptions, no skeletal or soft tissue abnormalities, and no cleft pallet. Oxidative stress biomarkers were close to the normal, and no increase in the malondialdehyde level was seen. Histopathological studies revealed normal tissue architecture of the selected organs, except kidney, in acute oral and subacute toxicity studies at 40 mg/kg. The study concluded that SF3 is safer if used as a drug.The Chikungunya virus (CHIKV) is an arbovirus belonging to the genus Alphavirus of the Togaviridae family. CHIKV is transmitted by the mosquitoes and causes Chikungunya fever. CHIKV outbreaks have occurred in Africa, Asia, Europe, and the countries of Indian and Pacific Oceans. In 2013, CHIKV cases were registered for the first time in the Americas on the Caribbean islands. There is currently no vaccine to prevent or medicines to treat CHIKV infection. The CHIKV nonstructural protease (nsP2) is a promising potential target for the development of drugs against CHIKV infection because this protein is one of the key components of the viral replication complex and is involved in multiple steps of virus infection. In this work, novel analogues of the potential CHIKV nsP2 protease inhibitor, first reported by Das et al. in 2016, were identified using molecular modeling methods, synthesized, and evaluated in vitro. The optimization of the structure of the inhibitor allowed to increase the antiviral activity of the compound 2-10 times. The possible mechanism of action of the identified potential inhibitors of the CHIKV nsP2 protease was studied in detail using molecular dynamics (MD) simulations. According to the MD results, the most probable mechanism of action is the blocking of conformational changes in the nsP2 protease required for substrate recognition and binding.For particles that escape from electrostatic precipitators (ESPs), inertial recapture is used to improve the efficiency of dust removal. A rod-grid inertial separator was designed. selleck compound The electrostatic and fluid flow particle tracking modules were selected in the model established by the COMSOL software, and the dust removal efficiency of the proposed dust separator was evaluated. When the flue gas velocity was 20 m·s-1, the diameter of the round rod was 8 mm, and the spacing of the pipes was 15 mm, the removal efficiency of PM2.5 and PM10 reached 27.8 and 84.6%, respectively. Experiments were performed under laboratory conditions and actual working conditions in a coal-fired power plant flue. Results showed that an inertial separator can achieve more than 60% efficiency in recapturing fly ashes that have escaped from ESPs. It can effectively remove fine particles and aerosol pollutants represented by PM2.5 and PM10.Shape-controlled platinum nanoparticles exhibit extremely high oxygen reduction activity. Platinum nanoparticles were synthesized by the reduction of a platinum complex in the presence of a soft template formed by organic surfactants in oleylamine. The formation of platinum nanoparticles was investigated using in situ small-angle X-ray scattering experiments. Time-resolved measurements revealed that different particle shapes appeared during the reaction. After the nuclei were generated, they grew into anisotropic rod-shaped nanoparticles. The shape, size, number density, reaction yield, and specific surface area of the nanoparticles were successfully determined using small-angle X-ray scattering profiles. link2 Anisotropic platinum nanoparticles appeared at a low reaction temperature (∼100 °C) after a short reaction time (∼30 min). The aspect ratio of these platinum nanoparticles was correlated with the local packing motifs of the surfactant molecules and their stability. link3 Our findings suggest that the interfacial structure between the surfactant and platinum nuclei can be important as a controlling factor for tailoring the aspect ratio of platinum nanoparticles and further optimizing the fuel cell performance.For a better understanding on the interaction between polyethyleneimine (PEI) and proteins, spectroscopic studies including UV-vis absorption, resonance Rayleigh scattering, fluorescence, and circular dichroism were conducted to reveal the conformational change of rabbit muscle lactate dehydrogenase (rmLDH) and related to the bioactivity of the enzyme. Regardless of the electrostatic repulsion, PEI could bind on the surface of rmLDH, a basic protein, via hydrogen binding of the dense amine groups and hydrophobic interaction of methyl groups. The competitive binding by PEI led to a reduction of the binding efficiency of rmLDH toward β-nicotinamide adenine dinucleotide, the coenzyme, and sodium pyruvate, the substrate. However, the complex formation with PEI induced a less ordered conformation and an enhanced surface hydrophobicity of rmLDH, facilitating the turnover of the enzyme and generally resulting in an increased activity. PEI of higher molecular weight was more efficient to induce alteration in the conformation and catalytic activity of the enzyme.Tryptophan-containing isoprenoid indole alkaloid natural products are well known for their intricate structural architectures and significant biological activities. Nature employs dimethylallyl tryptophan synthases (DMATSs) or aromatic indole prenyltransferases (iPTs) to catalyze regio- and stereoselective prenylation of l-Trp. Regioselective synthetic routes that isoprenylate cyclo-Trp-Trp in a 2,5-diketopiperazine (DKP) core, in a desymmetrizing manner, are nonexistent and are highly desirable. Herein, we present an elaborate report on Brønsted acid-promoted regioselective tryptophan isoprenylation strategy, applicable to both the monomeric amino acid and its dimeric l-Trp DKP. This report outlines a method that regio- and stereoselectively increases sp3 centers of a privileged bioactive core. We report on conditions involving screening of Brønsted acids, their conjugate base as salt, solvent, temperature, and various substrates with diverse side chains. Furthermore, we extensively delineate effects on regio- and stereoselection of isoprenylation and their stereochemical confirmation via NMR experiments. Regioselectively, the C3-position undergoes normal-isoprenylation or benzylation and forms exo-ring-fused pyrroloindolines selectively. Through appropriate prenyl group migrations, we report access to the bioactive tryprostatin alkaloids, and by C3-normal-farnesylation, we access anticancer drimentines as direct targets of this method. The optimized strategy affords iso-tryprostatin B-type products and predrimentine C with 58 and 55% yields, respectively. The current work has several similarities to biosynthesis, such as-reactions can be performed on unprotected substrates, conditions that enable Brønsted acid promotion, and they are easy to perform under ambient conditions, without the need for stoichiometric levels of any transition metal or expensive ligands.In the process industry, fault monitoring related to output is an important step to ensure product quality and improve economic benefits. In order to distinguish the influence of input variables on the output more accurately, this paper introduces a subalgorithm of fault-unrelated block partition into the prototype knockoff filter (PKF) algorithm for its improvement. The improved PKF algorithm can divide the input data into three blocks fault-unrelated block, output-related block, and output-unrelated block. Removing the data of fault-unrelated blocks can greatly reduce the difficulty of fault monitoring. This paper proposes a feature selection based on the Laplacian Eigen maps and sparse regression algorithm for output-unrelated blocks. The algorithm has the ability to detect faults caused by variables with small contribution to variance and proves the descent of the algorithm from a theoretical point of view. The output relation block is monitored by the Broyden-Fletcher-Goldfarb-Shanno method. Finally, the effectiveness of the proposed fault detection method is verified by the recognized Eastman process data in Tennessee.Chitosan/poly(vinyl alcohol)/amino-functionalized montmorillonite nanocomposite electrospun membranes with enhanced adsorption capacity and thermomechanical properties were fabricated and utilized for the removal of a model cationic dye (Basic Blue 41). Effects of nanofiller concentrations (up to 3.0 wt %) on the morphology and size of the nanofibers as well as the porosity and thermomechanical properties of the nanocomposite membranes are studied. It is shown that the incorporation of the nanoclay particles with ∼10 nm lateral sizes into the polymer increases the size of the pores by about 80%. To demonstrate the efficiency of the adsorbents, the dye removal rate is investigated as a function of pH, adsorbent dosage, dye concentration, and nanofiller loading. The highest and fastest dye removal occurs for the nanofibrous membranes containing 2 wt % nanofiller, where about 80% of the cationic dye is removed after 15 min. This performance is at least 20% better than the pristine chitosan/poly(vinyl alcohol) membrane. The thermal stability and compression resistance of the nanocomposite membranes are found to be higher than those of the pristine membrane. In addition, reusability studies show that the dye removal performance of this nanocomposite membrane reduces by only about 5% over four cycles. The adsorption kinetics is explained by the Langmuir isotherm model and is expressed by a pseudo-second-order kinetic mechanism that determines a spontaneous chemisorption process. The results of this study provide a valuable perspective on the fabrication of high-performance, reusable, and efficient electrospun fibrous nanocomposite adsorbents.Congruent lithium niobate single crystals with a RuMg co-dopant have been successfully grown using the Czochralski technique from the melt containing 0.02 mol % Ru with Mg of two varied concentrations (4.0 and 6.0 mol %). The effects of Ru and Mg co-doping on the crystalline quality were determined by high-resolution X-ray diffractometry, which confirmed that the crystalline quality is good and that the dopants are statistically distributed in the crystal. The Raman scattering analysis shows no change in the lattice vibration except a slight change in the peak width and intensity due to more asymmetry in the molecular charge, which leads to enhancement of the polarizability. The optical transmission spectra indicate that both the crystals have high optical transparency in the visible region, with a shift of the absorption edge toward shorter wavelengths, as compared to un-doped LN. The weak absorption band observed below 400 nm is attributed to Ru ions. The influence of co-doping in the electronic band gap energies is calculated by the Tauc relation.