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1.
Polymers (Basel) ; 14(22)2022 Nov 08.
Article in English | MEDLINE | ID: mdl-36432922

ABSTRACT

As technology advances toward ongoing circuit miniaturization and device size reduction followed by improved power density, heat dissipation is becoming a key challenge for electronic equipment. Heat accumulation can be prevented if the heat from electrical equipment is efficiently exported, ensuring a device's lifespan and dependability and preventing otherwise possible mishaps or even explosions. Hence, thermal management applications, which include altering the role of aerogels from thermally insulative to thermally conductive, have recently been a hot topic for 3D-aerogel-based thermal interface materials. To completely comprehend three-dimensional (3D) networks, we categorized and comparatively analyzed aerogels based on carbon nanomaterials, namely fibers, nanotubes, graphene, and graphene oxide, which have capabilities that may be fused with boron nitride and impregnated for better thermal performance and mechanical stability by polymers, including epoxy, cellulose, and polydimethylsiloxane (PDMS). An alternative route is presented in the comparative analysis by carbonized cellulose. As a result, the development of structurally robust and stiff thermally conductive aerogels for electronic packaging has been predicted to increase polymer thermal management capabilities. The latest trends include the self-organization of an anisotropic structure on several hierarchical levels within a 3D framework. In this study, we highlight and analyze the recent advances in 3D-structured thermally conductive aerogels, their potential impact on the next generation of electronic components based on advanced nanocomposites, and their future prospects.

2.
Phys Rev E ; 106(2-1): 024114, 2022 Aug.
Article in English | MEDLINE | ID: mdl-36109917

ABSTRACT

In this paper we write exactly solvable generalizations of one-dimensional quantum XY and Ising-like models by using 2^{d}-dimensional gamma matrices as the degrees of freedom on each site. We show that these models result in quadratic Fermionic Hamiltonians with Jordan-Wigner-like transformations. We illustrate the techniques using a specific case of four-dimensional gamma matrices and explore the quantum phase transitions present in the model.

3.
Biomed Res Int ; 2022: 9565136, 2022.
Article in English | MEDLINE | ID: mdl-35832850

ABSTRACT

To date, there is no satisfactory and effective therapy available to cure type 2 diabetes mellitus (T2DM). This present work is focused on plant extracts and the effect of saroglitazar and TET genes on oxidative stress and inflammation in vitro adipocytes. Aqueous extracts of Tamarindus indica and Momordica charantia seed have shown potent antidiabetic activity that decreases glucose levels in diabetic adipocytes. After seven and fourteen days, the sugar level in the blood was significantly reduced when plant extracts were supplemented. Lipid profiles including total cholesterol (TC), triglyceride (TGL), high-density lipoprotein (HDL), low-density lipoprotein (LDL), and very low-density lipoprotein (VLDL) showed a highly significant change as expected in adipocytes treated with glucose compared with controlled adipocytes (P < 0.001). Gene expression of catalase, superoxide dismutase (SOD1, SOD2), and glutathione peroxidase (GPx) are changed twice, thrice, and quadruplet, respectively. The level of interleukin-1 (IL1) and tumor necrosis factor-α (TNF-α) was restored but the interleukin-6 (IL6) and ten-eleven-translocation-1 (TET1) were completely knocked down by the use of saroglitazar. In comparison with the diabetic group, this supplementation significantly increased glycogen content and glucose-6-phosphate dehydrogenase activity. In the extract supplemented group, glucose-6-phosphatase, glucose-oxidizing enzyme, and glucose-phosphorylating enzyme activities were significantly reduced. After seven days of extract supplementation, these parameters were not resettled to a controlled level; however, after 14 days of supplementation, all parameters were restored to the control level. In addition to altering gene expression, TET enzymes may contribute to altered adiposity and its metabolic consequences. The purpose of this study is to examine new ideas and approaches for treating obesity, T2DM, and other associated metabolic disorders.


Subject(s)
Diabetes Mellitus, Experimental , Diabetes Mellitus, Type 2 , Momordica charantia , Tamarindus , Adipocytes/metabolism , Animals , Blood Glucose , Diabetes Mellitus, Experimental/metabolism , Diabetes Mellitus, Type 2/drug therapy , Diabetes Mellitus, Type 2/genetics , Down-Regulation , Gene Expression , Glucose , Hypoglycemic Agents/pharmacology , Inflammation/drug therapy , Inflammation/genetics , Lipoproteins, LDL/metabolism , Phenylpropionates , Plant Extracts/pharmacology , Pyrroles , Tamarindus/metabolism
4.
Eur Phys J E Soft Matter ; 36(10): 123, 2013 Oct.
Article in English | MEDLINE | ID: mdl-24158264

ABSTRACT

Diverse complex dynamical systems are known to exhibit abrupt regime shifts at bifurcation points of the saddle-node type. The dynamics of most of these systems, however, have a stochastic component resulting in noise-driven regime shifts even if the system is away from the bifurcation points. In this paper, we propose a new quantitative measure, namely, the propensity transition point as an indicator of stochastic regime shifts. The concepts and the methodology are illustrated for the one-variable May model, a well-known model in ecology and the genetic toggle, a two-variable model of a simple genetic circuit. The general applicability and usefulness of the method for the analysis of regime shifts is further demonstrated in the case of the mycobacterial switch to persistence for which experimental data are available.


Subject(s)
Models, Biological , Ecology/methods , Stochastic Processes
5.
Phys Biol ; 10(3): 036010, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23669271

ABSTRACT

Recently, a large number of studies have been carried out on the early signatures of sudden regime shifts in systems as diverse as ecosystems, financial markets, population biology and complex diseases. The signatures of regime shifts in gene expression dynamics are less systematically investigated. In this paper, we consider sudden regime shifts in the gene expression dynamics described by a fold-bifurcation model involving bistability and hysteresis. We consider two alternative models, models 1 and 2, of competence development in the bacterial population B. subtilis and determine some early signatures of the regime shifts between competence and noncompetence. We use both deterministic and stochastic formalisms for the purpose of our study. The early signatures studied include the critical slowing down as a transition point is approached, rising variance and the lag-1 autocorrelation function, skewness and a ratio of two mean first passage times. Some of the signatures could provide the experimental basis for distinguishing between bistability and excitability as the correct mechanism for the development of competence.


Subject(s)
Bacillus subtilis/genetics , Gene Expression Regulation, Bacterial , Models, Genetic , Gene Regulatory Networks , Systems Theory
6.
J Phys Condens Matter ; 22(1): 016004, 2010 Jan 13.
Article in English | MEDLINE | ID: mdl-21386239

ABSTRACT

We study the entanglement properties of a molecular three-qubit system described by the Heisenberg spin Hamiltonian with anisotropic exchange interactions and including an external magnetic field. The system exhibits first-order quantum phase transitions by tuning two parameters, x and y, of the Hamiltonian to specific values. The three-qubit chain is open-ended so that there are two types of pairwise entanglement: nearest-neighbour (nn) and next-nearest-neighbour (nnn). We calculate the ground and thermal state concurrences, quantifying pairwise entanglement, as a function of the parameters x, y and the temperature T. The entanglement threshold and gap temperatures are also determined as a function of the anisotropy parameter x. The results obtained are of relevance in understanding the entanglement features of the recently engineered molecular Cr(7)Ni-Cu(2+)-Cr(7)Ni complex which serves as a three-qubit system at sufficiently low temperatures.

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