176 research outputs found
Anti-Tumor Activity of a Novel Protein Obtained from Tartary Buckwheat
TBWSP31 is a novel antitumor protein that was isolated from tartary buckwheat water-soluble extracts. The objective of this paper was to investigate the anti-proliferative effects of TBWSP31 on breast cancer Bcap37cells and to explore its possible mechanism. After treatment of Bcap37 cells with TBWSP31, typical apoptotic morphological changes were observed by inverted microscopy and scanning electron microscopy (SEM), such as detachment from the culture plate, change to a round shape, cell shrinkage, the absence of obvious microvilli, plasma membrane blebbing, and formation of apoptotic bodies. Cell-cycle analysis revealed that treatment with TBWSP31 resulted in a G0/G1 arrest and prevented the cells from growing from G0/G1 phase to S phase, which was most prominent at 48 h. The expression of bcl-2 and Fas were detected quantitatively by FCM, which showed that TBWSP31 induced-apoptosis may be involved with the participation of Fas and bcl-2. These results suggest that TBWSP31 is a potential antitumor compound and that apoptosis induced by TBWSP31 is a key antitumor mechanism
31P NMR Investigation of the Superconductor LiFeP (Tc = 5 K)
We investigate the static and dynamic spin susceptibility of the 111 type
Fe-based superconductor LiFeP with Tc ~ 5 K through the measurement of Knight
shift 31K and the spin-lattice relaxation rate 1/T1 at 31P site by nuclear
magnetic resonance. The constant 31K, small magnitudes of 1/T1T, along with the
resistivity rho ~ T^2 all point to the weak spin correlations in LiFeP. 1/T1T
display small enhancement toward Tc, indicating that the superconductivity is
intimately correlated with the antiferromagnetic spin fluctuations.Comment: Accepted for publication in EP
(Sr3La2O5)(Zn1-xMnx)2As2: A Bulk Form Diluted Magnetic Semiconductor isostructural to the "32522" Fe-based Superconductors
A new diluted magnetic semiconductor system, (Sr3La2O5)(Zn1-xMnx)2As2, has
been synthesized and characterized. 10% Mn substitution for Zn in bulk form
(Sr3La2O5)Zn2As2 results in a ferromagnetic ordering below Curie temperature,
TC ~ 40 K. (Sr3La2O5)(Zn1-xMnx)2As2 has a layered crystal structure identical
to that of 32522-type Fe based superconductors, and represents the fifth DMS
family that has a direct counterpart among the FeAs high temperature
superconductor families.Comment: Accepted for publication in EP
The suppression of Curie temperature by Sr doping in diluted ferromagnetic semiconductor (La1-xSrx)(Zn1-yMny)AsO
(La1-xSrx)(Zn1-yMny)AsO is a two dimensional diluted ferromagnetic
semiconductor that has the advantage of decoupled charge and spin doping. The
substitution of Sr2+ for La3+ and Mn2+ for Zn2+ into the parent semiconductor
LaZnAsO introduces hole carriers and spins, respectively. This advantage
enables us to investigate the influence of carrier doping on the ferromagnetic
ordered state through the control of Sr concentrations in
(La1-xSrx)(Zn0.9Mn0.1)AsO. 10 % Sr doping results in a ferromagnetic ordering
below TC ~ 30 K. Increasing Sr concentration up to 30 % heavily suppresses the
Curie temperature and saturation moments. Neutron scattering measurements
indicate that no structural transition occurs for (La0.9Sr0.1)(Zn0.9Mn0.1)AsO
below 300 K.Comment: Submitted to EP
4-Ethoxyimino-N′-methoxypyrrolidin-1-ium-3-carboximidamidium dichloride
The title compound, C8H18N4O2
2+·2Cl−, contains two oxime groups. The methyl oxime group has a Z configuration, and the ethyl oxime group is disordered, with both Z and E configurations in occupancies of 0.840 (8) and 0.160 (8), respectively. In the crystal structure, there are a number of N—H⋯Cl hydrogen bonds
tert-Butyl 3-[N-(tert-butoxycarbonyl)methylamino]-4-methoxyimino-3-methylpiperidine-1-carboxylate
The title compound, C18H33N3O5, was prepared from N-tert-butoxycarbonyl-4-piperidone using a nine-step reaction, including condensation, methylation, oximation, hydrolysis, esterification, ammonolysis, Hoffmann degradation, tert-butoxycarbonyl protection and methylation. The E configuration of the methyloxime geometry of the compound is confirmed
The synthesis and characterization of 1111-type diluted magnetic semiconductors (La1-xSrx)(Zn1-xTMx)AsO (TM = Mn, Fe, Co)
The doping effect of Sr and transition metals Mn, Fe, Co into the direct-gap
semiconductor LaZnAsO has been investigated. Our results indicate that the
single phase ZrCuSiAs-type tetragonal crystal structure is preserved in
(La1-xSrx)(Zn1-xTMx)AsO (TM = Mn, Fe, Co) with the doping level up to x = 0.1.
While the system remains semiconducting, doping with Sr and Mn results in
ferromagnetic order with TC ~ 30K, and doping with Sr and Fe results in a spin
glass like state below ~6K with a saturation moment of ~0.02 muB/Fe, an order
of magnitude smaller than the ~0.4 muB/Mn of Sr and Mn doped samples. The same
type of magnetic state is observed neither for (Zn,Fe) substitution without
carrier doping, nor for Sr and Co doped specimens.Comment: Accepted for publication in EP
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