2 research outputs found
Modeling of electron mobility of gan at low temperature and low electric field
An analytical model at low temperature and low field electron mobility of GaN has been developed. The electron mobility in GaN have been calculated using Relaxation Time Approximation method considering elastic process of acoustic phonon deformation potential scattering, acoustic piezoelectric scattering and ionized impurity scattering, neutral impurity scattering, dislocation scattering. Ionized impurity scattering has been treated beyond the Born approximation using Dingle and Brooks- Herring analysis. The compensation ratio is used as a parameter with a realistic charge neutrality condition. Degeneracy is very important factor as it is used to imply different statistics (Maxwell – Boltzmann or Fermi – Dirac) at different temperature. Generalized M-B statistics are used throughout because the samples we have used to compare our results are highly Non-degenarate. The result shows that, the proposed model can accurately predict the electron mobility as a function of both the carrier concentration and the temperature upto 200 K. The discrepancy of this model above temperature 200 K presumably results from the following factors: ignoring the role of optical phonon, at low temperature consideration of parabolic band i.e. neglecting the effect of inter-velly scattering and ignoring the effect of very few interfacial charges in the degenerate layer at the GaN-substrate interface.
When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/2791
Disease-associated glycosylated molecular variants of human C-reactive protein activate complement-mediated hemolysis of erythrocytes in tuberculosis and Indian visceral leishmaniasis
Human C-reactive protein (CRP), as a mediator
of innate immunity, removed damaged cells by activating
the classical complement pathway. Previous studies have
successfully demonstrated that CRPs are differentially induced
as glycosylated molecular variants in certain pathological
conditions. Affinity-purified CRPs from two most
prevalent diseases in India viz. tuberculosis (TB) and
visceral leishmaniasis (VL) have differential glycosylation
in their sugar composition and linkages. As anemia is a
common manifestation in TB and VL, we assessed the
contributory role of glycosylated CRPs to influence hemolysis
via CRP-complement-pathway as compared to
healthy control subjects. Accordingly, the specific binding
of glycosylated CRPs with erythrocytes was established by
flow-cytometry and ELISA. Significantly, deglycosylated
CRPs showed a 7–8-fold reduced binding with erythrocytes
confirming the role of glycosylated moieties. Scatchard
analysis revealed striking differences in the apparent binding constants (104–105M−1) and number of binding
sites (106–107sites/erythrocyte) for CRP on patients’ erythrocytes
as compared to normal. Western blotting along with
immunoprecipitation analysis revealed the presence of
distinct molecular determinants on TB and VL erythrocytes
specific to disease-associated CRP. Increased fragility, hydrophobicity
and decreased rigidity of diseased-erythrocytes
upon binding with glycosylated CRP suggested membrane
damage. Finally, the erythrocyte-CRP binding was shown to
activate the CRP-complement-cascade causing hemolysis,
even at physiological concentration of CRP (10μg/ml).
Thus, it may be postulated that CRP have a protective role
towards the clearance of damaged-erythrocytes in these two
disease