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31.
Coffee cherry is a rich source of chlorogenic acids (CGAs) and caffeine. In this study we examined the potential antioxidant activity and enzyme inhibitory effects of whole coffee cherries (WCC) and their two extracts on α-amylase, α-glucosidase and acetylcholinesterase (AChE) activities, which are targets for the control of diabetes and Alzheimer’s diseases. Whole coffee cherry extract 40% (WCCE1) is rich in chlorogenic acid compounds, consisting of a minimum of 40% major isomers, namely 3-caffeoylquinic acids, 4-caffeoylquinic acids, 5-caffeoylquinic acids, 3,4-dicaffeoylquinic acid, 3,5-dicaffeoylquinic acid, 4,5-dicaffeoylquinic acid, 4-feruloylquinc acid, and 5-feruloylquinc acid. Whole coffee cherry extract 70% (WCCE2) is rich in caffeine, with a minimum of 70%. WCCE1 inhibited the activities of digestive enzymes α-amylase and α-glucosidase, and WCCE2 inhibited acetylcholinesterase activities with their IC50 values of 1.74, 2.42, and 0.09 mg/mL, respectively. Multiple antioxidant assays—including DPPH, ABTS, FRAP, ORAC, HORAC, NORAC, and SORAC—demonstrated that WCCE1 has strong antioxidant activity. 相似文献
32.
Debasish Ghosh Pradip Ghosh Golap Kalita Takuto Noda Chisato Takahashi Masaki Tanemura 《固体物理学:研究快报》2013,7(7):489-492
An efficient cathode material with high transparency (93%) based on conducting polymer poly(3,4‐ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) and single wall carbon nanotubes (SWCNTs) has been developed for the fabrication of highly transparent and flexible field electron emitters (FEE). This kind of material showed superior field emission (FE) performance with very high current density (10–3A/cm2) at very low electric field. The FE performance of the hybrid materials was dramatically improved compared to either SWCNTs and PEDOT:PSS. Thus the hybrid structures of conducting polymer and SWCNTs might be a good choice for use as a cathode material to enhance the FE performance and for potential application in future portable displays. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
33.
D. Kalita 《Linear and Multilinear Algebra》2013,61(6):743-756
34.
Kim Dmitry G. Kalita Elena V. Sharutin Vladimir V. Ovchinnikova Irina G. Ezhikova Marina А. Kodess Mikhail I. Slepukhin Pavel А. Vasilenko Anna V. 《Chemistry of Heterocyclic Compounds》2019,55(6):566-572
Chemistry of Heterocyclic Compounds - The sequence of condensation, alkylation, and halocyclization reactions during the synthesis of the target 2,3-dihydro[1,3]oxazolo[3,2-a]-pyridinium salts was... 相似文献
35.
V. F. Shamrai A. E. Karpikhin V. P. Sirotinkin V. I. Kalita D. I. Komlev 《Crystallography Reports》2014,59(2):179-185
The structure of hydroxyapatite plasma coatings on a titanium substrate has been investigated by the X-ray Rietveld method. The hydroxyapatite crystal structure in plasma-deposited samples is characterized by strong distortions of its main element (tetrahedral PO4 cluster) and coordination calcium polyhedra, as well as calcium deficit in the Ca2 site; however, these features do not change the main motif of the hydroxyapatite structure. The bond distortions in PO4 clusters are estimated by the Bauer method. It is shown that hydrothermal treatment leads to the almost complete recovery of the hydroxyapatite structure. 相似文献
36.
The Ramanujan Journal - In this paper, we develop a finite field analogue for one of the Lauricella series, $$F^{(n)}_A$$ . Extending results of Greene, a finite field analogue for the multinomial... 相似文献
37.
Tapan Ghosh Srikanth Birudula Kalyan Jyoti Kalita Dr. Ratheesh K. Vijayaraghavan 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(46):10501-10509
Control over the molecular packing in the solid state is of utmost importance in regulating the bulk optical properties of organic semiconductors. The electronic coupling between the molecules makes it possible to improve the properties of the bulk materials. This work reports an example of control over the selective formation of polymorphic single crystals of donor–acceptor-type small-molecule compound 25TR by 1) kinetic or 2) thermodynamic course of crystallisation to yield slipped stack (S) and cofacial (C) dimers in the single crystals. The distinct optical characteristics of the C-dimer and S-dimer are summarised. Both forms show significant excitonic interactions in the solid state, and the S-dimeric form has strong yellowish orange fluorescence, whereas the C-dimeric form is non-fluorescent in the crystalline state. DFT calculations and differential scanning calorimetric experiments revealed that the C-dimer polymorph is the thermodynamically stable form with a free energy offset of 0.43 eV in comparison with the S-dimer. Interestingly, the thermodynamically driven non-fluorescent single crystal was found to be convertible to its fluorescent form irreversibly by thermal trigger. The charge-carrier-transport characteristics of these two polymorphs were computed by using the Marcus–Hush formalism. The computations of the charge-carrier-transport behaviour revealed that the S-dimer ( 25TR(R) ) is ambipolar, whereas the C-dimer ( 25TR(Y) ) is predominantly n-type. 相似文献
38.
39.
Kangkan Sarmah Amlan J. Kalita Ankur K. Guha 《International journal of quantum chemistry》2023,123(1):e27006
Attachment of one electron to 1,2-diBeX-benzene and 1,2-diZnX-benzene derivatives leads to the formation of stronger Be Be and Zn Zn interaction compared to the neutral one. This is reflected in the dramatic shortening of the Be Be and Zn Zn distance. The formation of these 2-center-1-electron bonds have also been confirmed by topological survey of electron density using quantum theory of atoms in molecules and electron localization function. The formation of these bonds is expected to render stability to these radical anions. These radical anions are stable toward electron detachment and computed bond dissociation energy values are also significant. 相似文献
40.
The demand for quick, accurate, and affordable point-of-care (POC) devices increases with the advancement in the dimensions of nanotechnology and digital interfaces (Internet of Things). The future of diagnostic requires the platform which can provide us the following benefits i. e., on-site detection, qualitative as well as quantitative analysis, easy to use, portable, low sample requirement, cost-effective, and have multiplexing proficiency. Multiplex biosensing platforms (MBPs) have the above following advantages so are going to be mostly used in various healthcare applications in near future. MBPs have the potential to fulfill the ‘ASSURED’ criteria specified by the World Health Organization (WHO) for remote-limited settings. This review paper focuses on miniaturized platforms that have multiplexing benefits for the bioanalysis of different clinical samples related to various healthcare applications. In addition to this, screening of pesticides, antibiotics, and hazardous metal ions with these surface-engineered devices has also been accounted in food and environmental samples. Some of the advanced techniques including microfluidics (Lab-on-a-chip), wearable smart devices, and CRISPR/Cas system for multiplexing applications are briefly described here. Furthermore, various needs, challenges, and prospects in commercializing these multiplexed surface-engineered devices have been discussed in this review. 相似文献