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Numerical Model for the Determination of Erythrocyte Mechanical Properties and Wall Shear Stress in vivo From Intravital Microscopy.
The mechanical properties and deformability of Red Blood Cells (RBCs) are important determinants of blood rheology and microvascular hemodynamics. The objective of this study is to quantify the mechanical properties and wall shear stress experienced by the RBC membrane during capillary plug flow in vivo utilizing high speed video recording from intravital microscopy, biomechanical modeling, and computational methods. Capillaries were imaged in the rat cremaster muscle pre- and post-RBC transfusion of stored RBCs for 2-weeks. RBC membrane contours were extracted utilizing image processing and parametrized. RBC parameterizations were used to determine updated deformation gradient and Lagrangian Green strain tensors for each point along the parametrization and for each frame during plug flow. The updated Lagrangian Green strain and Displacement Gradient tensors were numerically fit to the Navier-Lame equations along the parameterized boundary to determined Lame's constants. Mechanical properties and wall shear stress were determined before and transfusion, were grouped in three populations of erythrocytes: native cells (NC) or circulating cells before transfusion, and two distinct population of cells after transfusion with stored cells (SC1 and SC2). The distinction, between the heterogeneous populations of cells present after the transfusion, SC1 and SC2, was obtained through principle component analysis (PCA) of the mechanical properties along the membrane. Cells with the first two principle components within 3 standard deviations of the mean, were labeled as SC1, and those with the first two principle components greater than 3 standard deviations from the mean were labeled as SC2. The calculated shear modulus average was 1.1±0.2, 0.90±0.15, and 12 ± 8 MPa for NC, SC1, and SC2, respectively. The calculated young's modulus average was 3.3±0.6, 2.6±0.4, and 32±20 MPa for NC, SC1, and SC2, respectively. o our knowledge, the methods presented here are the first estimation of the erythrocyte mechanical properties and shear stress in vivo during capillary plug flow. In summary, the methods introduced in this study may provide a new avenue of investigation of erythrocyte mechanics in the context of hematologic conditions that adversely affect erythrocyte mechanical properties
Development of CaF2 based Glass Ceramic.
In the present work the glass of composition 40 % SiO2, 5 % Al2O3, 15 % Na2O, 5 % CaO , 12,5 % NaF , 21 % CaF2 and 1.5 % Sb2O3 (mol%) was prepared to investigate the crystallization of CaF2 in the parent glass matrix. To accelerate the crystallization and to develop the up conversion fluorescence property Er2O3 was doped in 0.5% , 1 % and 1.5 % (mol%). The casted glass was subjected to thermal treatment between 600 – 750oC. To observe the effect of rare earth on crystallization glass samples were examined in DSC. Spectroscopic property of the base glasses were studied using UV-Visible spectrophotometer. Phase authentication was carried out using X-Ray diffraction analysis
Analytical profile of Arka Taila - An Ayurvedic oil based medicine used in Karnasrava (Otomycosis)
Otomycosis denotes diffuse otitis externa due to fungal infections. The fungii are usually secondary invaders of the tissue rendered susceptible by bacterial infection, physical injury or excessive accumulation of cerumen in the external auditory canal. Karnasraava means discharge from ear which can be correlated with otorrhoea. Karnasraava (discharge) is one of symptom of otomycosis. Arka Taila has been mentioned in Shaarangadhara is very simple formula having ingredients i.e. Haridraa (Curcuma longa), Arka Patra Swarasa (Calotropis procera) and Sarshapa Taila (Brassica campetries). The quality control parameters resulted after scientific evaluation of Arka Taila can be used as reference standard for quality control or quality assurance of a pharmaceutical industry in order to have a proper quality check over its preparation and processing
Analytical profile of Kushtha (Saussurea lappa) extensively used medicinal plant in Ayurveda system of medicine
Ayurveda is one of the most ancient medical sciences of the world. It is considered as the Upaveda of Atharvaveda. Kushtha (Saussurea lappa - C.B.Clarke) has been mentioned in various texts of Ayurveda. Acharya Charaka has incorporated Kushtha in more than 100 formulations. It is called similar activity as divine plant Soma. It grows nearby Soma in Himalayas. Kushtha (Saussurea lappa. – C.B.Clarke) is used for the treatment of disease and novel drug entities continue to be developed through research into their constituents. So much adulteration and sub standard quality drug samples are found in the name of Kushtha (Saussurea lappa – C.B.Clarke) in the market. Analytical and physicochemical profiles for standardization of medicinal plants is need of hour. Costunolide can be marker compound for the identification of Kushtha (Saussurea lappa. – C.B.Clarke.
Evidence of Cooper pair pumping with combined flux and voltage control
We have experimentally demonstrated pumping of Cooper pairs in a
single-island mesoscopic structure. The island was connected to leads through
SQUID (Superconducting Quantum Interference Device) loops. Synchronized flux
and voltage signals were applied whereby the Josephson energies of the SQUIDs
and the gate charge were tuned adiabatically. From the current-voltage
characteristics one can see that the pumped current increases in 1e steps which
is due to quasiparticle poisoning on the measurement time scale, but we argue
that the transport of charge is due to Cooper pairs.Comment: 4 page
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