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131.
Natural products in the form of functional foods have become increasingly popular due to their protective effects against life-threatening diseases, low risk of adverse effects, affordability, and accessibility. Plant components such as phytosterol, in particular, have drawn a lot of press recently due to a link between their consumption and a modest incidence of global problems, such as Type 2 Diabetes mellitus (T2DM), cancer, and cardiovascular disease. In the management of diet-related metabolic diseases, such as T2DM and cardiovascular disorders, these plant-based functional foods and nutritional supplements have unquestionably led the market in terms of cost-effectiveness, therapeutic efficacy, and safety. Diabetes mellitus is a metabolic disorder categoriszed by high blood sugar and insulin resistance, which influence major metabolic organs, such as the liver, adipose tissue, and skeletal muscle. These chronic hyperglycemia fallouts result in decreased glucose consumption by body cells, increased fat mobilisation from fat storage cells, and protein depletion in human tissues, keeping the tissues in a state of crisis. In addition, functional foods such as phytosterols improve the body’s healing process from these crises by promoting a proper physiological metabolism and cellular activities. They are plant-derived steroid molecules having structure and function similar to cholesterol, which is found in vegetables, grains, nuts, olive oil, wood pulp, legumes, cereals, and leaves, and are abundant in nature, along with phytosterol derivatives. The most copious phytosterols seen in the human diet are sitosterol, stigmasterol, and campesterol, which can be found in free form, as fatty acid/cinnamic acid esters or as glycosides processed by pancreatic enzymes. Accumulating evidence reveals that phytosterols and diets enriched with them can control glucose and lipid metabolism, as well as insulin resistance. Despite this, few studies on the advantages of sterol control in diabetes care have been published. As a basis, the primary objective of this review is to convey extensive updated information on the possibility of managing diabetes and associated complications with sterol-rich foods in molecular aspects.  相似文献   
132.
The precision lattice parameters of osmium dioxide have been determined at different temperatures, in the temperature range 30–444 °C, using a Unicam high temperature powder camera 19 cm in diameter and CuKα radiation. The data have been used to evaluate the coefficients of thermal expansion at various temperatures by a graphical method. The ‘a’ parameter increases non-linearly with increasing temperature while the ‘c’ parameter remains constant throughout the range of temperature studied indicating a zero coefficient of expansion along the c-direction. The abnormal thermal behaviour of this compound is explained in terms of the electronic configuration of the d-shell of the cation.  相似文献   
133.
Samples with the nominal composition Bi2Sr2CaCu2Oy with na doped at the Ca site and K doped at the Sr site are prepared by solid state reaction method. From the X-ray diffraction data it is found that all the the samples have exhibited a single phase 2212. The D.C. electrical resistivity data show that for Na-doped samples the Tc (zero) varies from 80 K to 85 K and for K-doped samples it is from 79 K to 82 K. The loss of oxygen from these samples around 400°C was confirmed by high temperature dilatometry. The variation of the thermal expansion coefficient (“α”) with temperature for different alkali dopings are discussed. Also the samples with the nominal composition Bi4Sr3Ca3Cu4−xAgxOy (with x = 0, 0.1, 0.2, 0.3) were studied.  相似文献   
134.
135.
A dual reactant/catalyst role of glyoxylic acid in the reaction of isatoic anhydride with various amines afforded a novel, robust and rapid synthesis of 3-(un)substituted quinazolin-4(3H)-ones. This metal catalyst-free reaction proceeds via an unusual and unexpected cleavage of C–C bond. A shorter and common route to two alkaloids, that is, rutaecarpine and evodiamine is also accomplished.  相似文献   
136.
Transport in Porous Media - A methodology has been developed to create a pore network model (PNM) from the geometrical/topological information extracted from the micro-tomographic images of a...  相似文献   
137.
138.
A simple and convenient methodology for selective sulfonation of aromatic compounds using sulfuric acid under sonication is described. The present methodology shows a considerable enhancement in the reaction rate along with improved selectivity compared with the reactions performed under silent conditions. The effect of various parameters such as agitation speed, sulfuric acid concentration, and temperature on reaction system have been investigated and are explained on the basis of ultrasonically generated cavitational effects.  相似文献   
139.
We report, herein, the results of an in depth study and concomitant analysis of the AC conduction [σ′(ω): f=20 Hz to 2 MHz] mechanism in a reduced graphene oxide–zinc sulfide (RGO–ZnS) composite. The magnitude of the real part of the complex impedance decreases with increase in both frequency and temperature, whereas the imaginary part shows an asymptotic maximum that shifts to higher frequencies with increasing temperature. On the other hand, the conductivity isotherm reveals a frequency‐independent conductivity at lower frequencies subsequent to a dispersive conductivity at higher frequencies, which follows a power law [σ′(ω)∝ωs] within a temperature range of 297 to 393 K. Temperature‐independent frequency exponent ′s′ indicates the occurrence of phonon‐assisted simple quantum tunnelling of electrons between the defects present in RGO. Finally, this sample follows the “time–temperature superposition principle”, as confirmed from the universal scaling of conductivity isotherms. These outcomes not only pave the way for increasing our elemental understanding of the transport mechanism in the RGO system, but will also motivate the investigation of the transport mechanism in other order–disorder systems.  相似文献   
140.
The aep-PNA is a chiral and cyclic PNA analogue, which has a stronger and base dependent binding affinity with complementary DNA. To understand the base dependent properties at monomer level, the structural studies of aep-PNA-(T/C/A) monomers have been carried out focussing on the conformational analysis of pyrrolidine ring pucker in aep-PNA by 1H NMR and the coupling constant data fitted into PSEUROT software. The results indicate that the type of pyrrolidine pucker depends on the electronic nature of substituent, implying the effect of pyrimidine or purine substituents in determining the ring pucker in monomers. This may consequently influence the aep-PNA oligomer conformation. Since pyrrolidine nucleic acids have emerged as an important class of PNA analogues, present results may have importance for their future development.  相似文献   
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