Molecular Basis for a Simple, Specific Test for S Hemoglobin: the Murayama Test

1970 ◽  
Vol 16 (11) ◽  
pp. 945-950 ◽  
Author(s):  
Robert M Nalbandian ◽  
Raymond L Henry ◽  
Bruce M Nichols ◽  
Frank R Camp ◽  
Paul L Wolf

Abstract The Murayama test, a new, specific test for S hemoglobin, is based on the molecular mechanism of sickling for S hemoglobin proposed by Murayama [Clin. Chem. 14, 578 (1967)]. The test depends on a feature of molecular structure: hydrophobic bonds formed between interacting tetramers by the no. 6 valine, which is substituted for glutamic acid near the N-terminal end of each β S globin chain. Existence of these particular hydrophobic bonds is manifested in deoxygenated, concentrated hemolysates by reversible sol— gel transformations at 0° and 37°C. In such systems, demonstration of reversible, temperature-dependent sol—gel transformations (a negative temperature coefficient of gelation) is specific for S hemoglobin or the S structural variant, hemoglobin C (Harlem). The test is simple, has clear endpoints, will detect both homozygous and heterozygous S hemoglobin, and is specific. A practical approach is suggested to the precise identification of S and non-S sickling hemoglobins in the diagnostic laboratory. The close agreement between Murayama’s hypothesis for sickling in S hemoglobin and our results with 29 cases of S hemoglobin and 37 controls further support his views.

2020 ◽  
Vol 15 (1) ◽  
Author(s):  
Mingming Yang ◽  
Longlong Wang ◽  
Xiaofen Qiao ◽  
Yi Liu ◽  
Yufan Liu ◽  
...  

Abstract The defects into the hexagonal network of a sp2-hybridized carbon atom have been demonstrated to have a significant influence on intrinsic properties of graphene systems. In this paper, we presented a study of temperature-dependent Raman spectra of G peak and D’ band at low temperatures from 78 to 318 K in defective monolayer to few-layer graphene induced by ion C+ bombardment under the determination of vacancy uniformity. Defects lead to the increase of the negative temperature coefficient of G peak, with a value almost identical to that of D’ band. However, the variation of frequency and linewidth of G peak with layer number is contrary to D’ band. It derives from the related electron-phonon interaction in G and D’ phonon in the disorder-induced Raman scattering process. Our results are helpful to understand the mechanism of temperature-dependent phonons in graphene-based materials and provide valuable information on thermal properties of defects for the application of graphene-based devices.


2021 ◽  
Author(s):  
N MURALI

Abstract Al substituted Ni0.4Zn0.35Cu0.25Fe2-xAlxO4 (x = 0.00, 0.05, 0.10, 0.15, 0.20) samples is synthesized using the sol-gel auto-combustion process. X-ray diffraction shows its cubic spinel structure. The lattice constant decreases as the Al3+ content increases. The sizes of the crystallites are also decreasing in the range of 32.15 nm to 22.89 nm. The wavenumbers of tetrahedral and octahedral sites sighted in the FT-IR spectra are similar to that of the precursor. The increment in the Al3+ content increases the DC conductivity. The electrical resistivity decrease with an increase in the temperature, i.e., it has a negative temperature coefficient with resistance similar to semiconductors. VSM results show their isotropic nature forming single domain ferrimagnetic particles. The resultant material is widely significant, as indicated by its result.


2021 ◽  
Author(s):  
K. Chandramouli ◽  
P. Anantha Rao ◽  
B. Suryanarayana ◽  
Vemuri Raghavendra ◽  
D. Parajuli ◽  
...  

Abstract Cu substituted Ni0.5Zn0.5-xCuxFe2O4 (x = 0, 0.1, 0.2, 0.3 and 0.4) samples is synthesized using the sol-gel auto-combustion process. X-ray diffraction shows its cubic spinel structure. The lattice constant decreases as the Cu content increases. The sizes of the crystallites are also decreasing in the range of 42.68 nm to 21.75 nm. The wavenumbers of tetrahedral and octahedral sites sighted in the FTIR spectra are similar to that of the precursor. The increment in the copper content increases the DC conductivity. The electrical resistivity decrease with increase in the temperature, i.e. it has a negative temperature coefficient with resistance similar to semiconductors. The remnant ratios R obtained from VSM show their isotropic nature forming single domain ferrimagnetic particles. The resultant material is widely significant, as indicated by its result.


2021 ◽  
Author(s):  
Kanta Jayadev ◽  
M. K. Raju ◽  
N MURALI ◽  
Parajuli D ◽  
K. Samatha

Abstract Co substituted Ni0.3-xCoxCu25Zn0.45Fe2O4 (x = 0, 0.05, 0.1, 0.15 and 0.2) samples is synthesized using the sol-gel auto-combustion process. X-ray diffraction shows its cubic spinel structure. The lattice constant decreases as the Co content increases. The sizes of the crystallites are in the range of 20.18–26.24 nm. The wavenumbers of tetrahedral and octahedral sites sighted in the FTIR spectra are similar to that of the precursor. The increment on the Co content increases the DC conductivity. The electrical resistivity decrease with increase in the temperature, i.e. it has a negative temperature coefficient with resistance similar to semiconductors. The remnant ratios R obtained from VSM show their isotropic nature forming single domain ferrimagnetic particles. The resultant material is widely significant, as indicated by its result.


2018 ◽  
Vol 1 (1) ◽  
pp. 21-25
Author(s):  
R Revathi ◽  
R Karunathan

Indium Telluride thin films were prepared by thermal evaporation technique. Films were annealed at 573K under vacuum for an hour. Both as-deposited and annealed films were used for characterization. The structural parameters were discussed on the basis of annealing effect for a film of thickness 1500 Å. Optical analysis was carried out on films of different thicknesses for both as - deposited and annealed samples. Both the as- deposited and annealed films exhibit direct and allowed transition. Electrical resistivity measurements were made in the temperature range of 303-473 K using Four-probe method. The calculated resistivity value is of the order of 10-6 ohm meter. The activation energy value decreases with increasing film thickness. The negative temperature coefficient indicates the semiconducting nature of the film.


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