Search results for "Tatin"
showing 10 items of 700 documents
Two-laser multiphoton adiabatic passage in the frame of the Floquet theory. Applications to (1+1) and (2+1) STIRAP
1998
We develop an adiabatic two-mode Floquet theory to analyse multiphoton coherent population transfer in N-level systems by two delayed laser pulses, which is a generalization of the three-state stimulated Raman adiabatic passage (STIRAP). The main point is that, under conditions of non-crossing and adiabaticity, the outcome and feasibility of a STIRAP process can be determined by the analysis of two features: (i) the lifting of degeneracy of dressed states at the beginning and at the end of the laser pulses, and (ii) the connectivity of these degeneracy-lifted branches in the quasienergy diagram. Both features can be determined by stationnary perturbation theory in the Floquet representation…
Stability of electrically conducting liquid flow driven by a rotating magnetic dipole in a ring channel
2020
The stability of electrically conducting liquid flow in a cylindrical ring channel is studied numerically. The flow is driven by a rotating magnetic dipole placed at the ring’s center. Depending on ring’s width, two distinct flow regimes are observed. In a narrow ring, the flow itself and its instability resemble the related rotating magnetic field driven flow in a cylinder. This changes in a wide ring when an intense radial jet develops on the midplane. Within this jet, the driving magnetic force is overwhelmed by inertial and viscous forces similar to how it occurs in the boundary layer flow. The instability develops as an azimuthally periodic wave-like deformation of this jet. Non-unifor…
Permanent magnet bottom-stirred swirling flow in coaxial shallow cylindrical containers
2021
Here, an original rotating permanent magnet (RPM) system placed coaxially with the liquid metal container is studied as an effective means of generating flow in shallow cylinders for potential application in aluminum metallurgy (e.g., for ladle stirring and metal dosing). The studied RPM system generates volume force with strong axial variation and force maximum near the radial midpoint. The numerical and experimental data show that, in the shallow cylinder case, the azimuthal velocity follows the force radial distribution. The resulting velocity maximum occurs near the radial midpoint, unlike in the traditional rotating magnetic field (RMF) stirrer systems, where the velocity maximum occur…
The role of red yeast rice (RYR) supplementation in plasma cholesterol control: A review and expert opinion.
2019
1. Preamble : Hypercholesterolemia is a major risk factor for atherosclerotic cardiovascular disease (ASCVD) [1]. Increased levels of low density lipoprotein cholesterol (LDL-C) are associated with an increased risk of coronary heart disease (CHD) and many clinical trials have shown that reducing LDL-C levels significantly reduced the CHD and CVD risk [[2], [3], [4], [5]]. Thus LDL-C-lowering is the main approach for the management of cardiovascular disease. Current guidelines suggest LDL-C levels targets based on the individual CV risk; such targets can be achieved by several means, which include both lifestyle changes and pharmacological approaches [6], with statins being the cornerstone …
Exenatide prevents statin-related LDL receptor increase and improves insulin secretion in pancreatic beta cells (1.1E7) in a protein kinase A-depende…
2022
Statins are primary drugs in the treatment of hyperlipidemias. This group of drugs is known for its beneficial pleiotropic effects (e.g., reduction of inflammatory state). However, a growing body of evidence suggests its diabetogenic properties. The culpable mechanism is not completely understood and might be related to the damage to pancreatic beta cells. Therefore, we conceived an in vitro study to explore the impact of atorvastatin on pancreatic islet beta cells line (1.1.E7). We evaluated the influence on viability, insulin, lowdensity lipoprotein (LDL) receptor, and proprotein convertase subtilisin/kexin type 9 (PCSK9) expression. A significant drop in mRNA for proinsulin and insulin e…
Genetic background in nonalcoholic fatty liver disease: A comprehensive review
2015
In the Western world, nonalcoholic fatty liver disease (NAFLD) is considered as one of the most significant liver diseases of the twenty-first century. Its development is certainly driven by environmental factors, but it is also regulated by genetic background. The role of heritability has been widely demonstrated by several epidemiological, familial, and twin studies and case series, and likely reflects the wide inter-individual and inter-ethnic genetic variability in systemic metabolism and wound healing response processes. Consistent with this idea, genome-wide association studies have clearly identified Patatin-like phosholipase domain-containing 3 gene variant I148M as a major player i…
Plasma clearance of human low-density lipoprotein in human apolipoprotein B transgenic mice is related to particle diameter.
2004
To test for intrinsic differences in metabolic properties of low-density lipoprotein (LDL) as a function of particle size, we examined the kinetic behavior of 6 human LDL fractions ranging in size from 251 to 265 A injected intravenously into human apolipoprotein (apo) B transgenic mice. A multicompartmental model was formulated and fitted to the data by standard nonlinear regression using the Simulation, Analysis and Modeling (SAAM II) program. Smaller sized LDL particles (251 to 257 A) demonstrated a significantly slower fractional catabolic rate (FCR) (0.050 +/- 0.045 h(-1)) compared with particles of larger size (262 to 265 A) (0.134 +/- -0.015 h(-1), P.03), and there was a significant …
P3‐039: Axonal neuritic pathology induces early presynaptic alterations in ps1/APP Alzheimer's mice hippocampus
2011
Loss of neurons in the hippocampus correlates with memory impairment in AD. Significant early reduction in the numerical density of hippocampal SOM interneurons was found in single (APPswe) and double (APPswe/ PS1dE9 and APPswe/TauP301S-G272V) transgenic models based on APP over expression and amyloid production. However, this inhibitory population was unaffected in age-matched single PS1 and tau transgenic mice as well as nontransgenic controls. Whereas SOM neuron loss in APPswe/PS1dE9 was associated to the onset of extracellular amyloid pathology in double APP/ tau mice this loss preceded plaque formation. Conclusions: As in human AD, somatostatin cell loss is a common early pathological …
Combination of the novel farnesyltransferase inhibitor RPR130401 and the geranylgeranyltransferase-1 inhibitor GGTI-298 disrupts MAP kinase activatio…
1999
To test the Kirsten-Ras (Ki-Ras) alternative prenylation hypothesis in malignant transformation, we used a novel farnesyltransferase inhibitor competitive to farnesyl-pyrophosphate, RPR130401, and a CaaX peptidomimetic geranylgeranyltransferase-1 inhibitor GGTI-298. In Ki-Ras-overexpressing transformed adrenocortical cells, RPR130401 at 1-10 microM inhibited very efficiently the [(3)H]farnesyl but not [(3)H]geranylgeranyl transfer to Ras. However, proliferation of these cells was only slightly sensitive to RPR130401 (IC(50)=30 microM). GGTI-298 inhibited the growth of these cells with an IC(50) of 11 microM but cell lysis was observed at 15 microM. The combination of 10 microM RPR130401 and…
Asociación de pravastatina y fenofibrato (Pravafenix®). Estudios de seguridad
2014
Resumen Aunque el colesterol unido a lipoproteinas de baja densidad (cLDL) es el objetivo primario de tratamiento para reducir el riesgo cardiovascular, el incremento de trigliceridos y el descenso del colesterol unido a lipoproteinas de alta densidad (cHDL) constituyen el denominado riesgo cardiovascular residual. El tratamiento con estatinas asociado a fibratos es una posibilidad real de tratamiento del riesgo cardiovascular total. Sin embargo, esta asociacion puede con frecuencia asociarse a efectos adversos, especialmente musculares y hepaticos. Por sus caracteristicas farmacologicas, la asociacion de pravastatina con fenofibrato puede ser eficaz y segura, con escasos efectos secundario…