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141.
Matheus Nunes da Rocha Márcia Machado Marinho Alexandre Magno Rodrigues Teixeira Emmanuel Silva Marinho Hélcio Silva dos Santos 《印度化学会志》2022,99(7):100535
Considered one of the chronic diseases in a global state of emergency, diabetes mellitus (DM) may cover an area of 629 million people affected by 2045. The main route of hyperglycemia in the human body is associated with the action of the enzyme aldose reductase on glucose molecules, resulting in the accumulation of sorbitol in blood and tissue cells. Thus, the present study is a high-throughput virtual screening (HTS) of the various molecular datasets available online, as well as an investigation of the pharmacokinetic properties of absorption, distribution, metabolism, excretion, and toxicity (ADMET) and enzyme inhibition aldose reductase from a series of derivatives of rhodanine-3-acetic acid chalcones (D1-8). Four derivatives (D1-4) showed greater oral bioavailability, as they are anions of low relative polarity, showing better viability to interact with the aldose reductase target with a low toxic response to the host. 相似文献
142.
C. Lucas I. Eiroa M. R. Nunes P. A. Russo M. M. L. Ribeiro Carrott M. I. da Silva Pereira M. E. Melo Jorge 《Journal of Solid State Electrochemistry》2009,13(6):943-950
The electrochemical properties of Ca1 − x
Ce
x
MnO3 perovskite-type oxide electrode have been investigated by cyclic voltammetry in Na2SO4 aqueous solutions with pH 14. The structural and morphological characterizations have also been investigated and the information
used to interpret the electrochemical behavior. An estimation of the electrode’s capacitance and roughness factor has been
obtained by means of cyclic voltammetry. The specific capacitance and consequently the roughness factor values are affected
by the presence of Ce ions in the oxide. These findings are in agreement with the increase of the oxide-specific surface area
by the introduction of Ce ion. The open-circuit potential and the voltammetric patterns are dependent on the presence of Ce
ion in the electrodes and support that the surface electrochemistry of the perovskite oxide electrodes is governed by the
Mn4+–Mn3+ redox couple. 相似文献
143.
In this paper, the large time decay of the magneto-micropolar fluid equations on \(\mathbb {R}^n\) (\( n=2,3\)) is studied. We show, for Leray global solutions, that \( \Vert ({\varvec{u}},{\varvec{w}},{\varvec{b}})(\cdot ,t) \Vert _{{L^2(\mathbb {R}^n)}} \rightarrow 0 \) as \(t \rightarrow \infty \) with arbitrary initial data in \( L^2(\mathbb {R}^n)\). When the vortex viscosity is present, we obtain a (faster) decay for the micro-rotational field: \( \Vert {\varvec{w}}(\cdot ,t) \Vert _{{L^2(\mathbb {R}^n)}} = o(t^{-1/2})\). Some related results are also included. 相似文献
144.
The chemistry of trifluoromethyl azafulvenium methides was explored leading to a new route to trifluoromethylpyrrole-annulated systems. The first evidence of azafulvenium methides acting as 1,3-dipoles is reported. These azafulvenium methides showed site selectivity in the reaction with strong electron-deficient dipolarophiles leading exclusively to 1,3-cycloadducts. In the cycloaddition with less-activated dipolarophiles 1,7-cycloadducts resulting from [8π+2π] cycloaddition are also formed. FMO analysis of the cycloaddition reactions allowed the rationalization of the observed selectivity. 相似文献
145.
Mário A. P. Nunes Hélder Vila-Real Pedro C. B. Fernandes Maria H. L. Ribeiro 《Applied biochemistry and biotechnology》2010,160(7):2129-2147
A synthetic polymer, polyvinyl alcohol (PVA), a cheap and nontoxic synthetic polymer to organism, has been ascribed for biocatalyst
immobilization. In this work PVA–alginate beads were developed with thermal, mechanical, and chemical stability to high temperatures
(<80 °C). The combination of alginate and bead treatment with sodium sulfate not only prevented agglomeration but produced
beads of high gel strength and conferred enzyme protection from inactivation by boric acid. Naringinase from Penicillium decumbens was immobilized in PVA (10%)–alginate beads with three different sizes (1–3 mm), at three different alginate concentrations
(0.2–1.0%), and these features were investigated in terms of swelling ratio within the beads, enzyme activity, and immobilization
yield during hydrolysis of naringin. The pH and temperature optimum were 4.0 and 70 °C for the PVA–alginate-immobilized naringinase.
The highest naringinase activity yield in PVA (10%)–alginate (1%) beads of 2 mm was 80%, at pH 4.0 and 70 °C. The Michaelis
constant (K
Mapp) and the maximum reaction velocity (V
maxapp) were evaluated for both free (K
Mapp = 0.233 mM; V
maxapp = 0.13 mM min−1) and immobilized naringinase (K
Mapp = 0.349 mM; V
maxapp = 0.08 mM min−1). The residual activity of the immobilized enzyme was followed in eight consecutive batch runs with a retention activity
of 70%. After 6 weeks, upon storage in acetate buffer pH 4 at 4 °C, the immobilized biocatalyst retained 90% of the initial
activity. These promising results are illustrative of the potential of this immobilization strategy for the system evaluated
and suggest that its application may be effectively performed for the entrapment of other biocatalysts. 相似文献
146.
Computational Management Science - In the application of machine learning to real-life decision-making systems, e.g., credit scoring and criminal justice, the prediction outcomes might discriminate... 相似文献
147.
Pedro Nunes Angelis Juliana Casarin Affonso Celso Gonçalves Júnior Luana Rianne Rocha Maiyara Carolyne Prete César Ricardo Teixeira Tarley 《Electroanalysis》2022,34(5):854-862
This paper reports the development of a simple electroanalytical method for imazethapyr (IMT) determination in rice samples based on molecularly imprinted polymer and functionalized carbon black paste electrode (MIP-fCBPE). Carbon black (CB) was functionalized by the insertion of oxygenated functional groups upon acid treatment with HNO3 and H2SO4. The functionalized carbon black (fCB) presented higher performance for IMT determination than the CB without functionalization. The insertion of molecularly imprinted polyvinylimidazole (MIP-VN) in the fCBPE promoted a significant increase in the cathodic peak current even at low proportions (7.5 % w/w) due to the specific binding sites for IMT recognition. For IMT determination, DPV parameters were optimized by the Doehlert matrix applying 0.1 V for 60 s as pre-treatment in acetate buffer solution (pH 3.0) as supporting electrolyte. The proposed method showed low limit of detection (0.03 μmol L−1), a wide linear range (0.10–70.00 μmol L−1), and good precision in terms of repeatability of intraday measures (RSD%=3.6). The method was applied in rice samples after microwave-assisted extraction of IMT and the accuracy of the method was evaluated by addition/recovery assays (96.3–105.7 %), being statistically attested using HPLC-DAD as reference technique. 相似文献
148.
Helena H. Chubatsu Nunes Trinh-Don Nguyen Thu-Thuy T. Dang 《Current Opinion in Green and Sustainable Chemistry》2022
Many small-molecule chemicals from plants display extraordinarily complex structures and potent bioactivities with significant pharmacological and industrial implications. While the medicinal and economic relevance of plants' bioactive compounds is widely recognized, their industrial-scale chemical synthesis for distribution and development of new derivatives is hampered by challenges associated with their structural complexity. Extraction from the native plants is usually not viable due to the chemicals' low natural abundance, and the plants’ sub-optimal growing conditions due to climate change and the destruction of natural habitats. All of these challenges ultimately highlight the need to expand the (bio)chemical toolbox with strategies that support continuous discovery and sustainable production of relevant chemicals. This article highlights some of the most recent discoveries of plant-derived biocatalysts and how they pave the way for more sustainable and greener approaches to produce chemicals with unmatched complexity and applications. 相似文献
149.
Costa Renyer A. da Silva Jonathas Nunes Oliveira Kelson M. T. Dutra Lívia M. Costa Emmanoel V. 《Structural chemistry》2020,31(3):1223-1243
Structural Chemistry - Diterpenes are a class of secondary metabolites that attract much attention due to the numerous biological activities presented, such as antimicrobial, antiviral,... 相似文献
150.
Poly(ether ketone ketone) was sulfonated using fumic sulfuric acid and used for preparation of proton conductive membranes. The sulfonation degree was evaluated by elemental and thermal analysis and the IEC values were determined by titration. The proton conductivity of membranes with sulfonation degrees up to 70% was determined as a function of temperature by impedance spectroscopy. Membranes with sulfonation degree 38–70% were tested in DMFC experiments. Their performance was comparable to Nafion® with the same pretreatment and clearly better than sulfonated poly(ether ether ketone) membranes with similar functionalization. The methanol crossover was lower than that of Nafion® in the same conditions. 相似文献