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1.

Background  

The adenine nucleotide translocator 1 (Ant1) is an inner mitochondrial membrane protein involved with energy mobilization during oxidative phosphorylation. We recently showed that rodent Ant1 is upregulated by transforming growth factor-beta (TGF-β) in reactive astrocytes following CNS injury. In the present study, we describe the molecular mechanisms by which TGF-β1 regulates Ant1 gene expression in cultured primary rodent astrocytes.  相似文献   
2.
We study the long-time relaxation of magnetization in a disordered linear chain of Ising spins from an initially aligned state. The coupling constants are ferromagnetic and nearest-neighbor only, taking valuesJ 0 andJ 1 with probabilitiesp and 1–p, respectively. The time evolution of the system is governed by the Glauber master equation. It is shown that for large timest, the magnetizationM(t) varies as [exp(–0 t](t), where 0 is a function of the stronger bond strengthJ 0 only, and (t) decreases slower than an exponential. For very long times, we find that ln (t) varies as –t 1/3. For low enough temperatures, there is an intermediate time regime when ln (t) varies as –t 1/2. The results can be extended to more general probability distributions of ferromagnetic coupling constants, assuming thatM(t) can only increase if any bond in the chain is strengthened. If the coupling constants have a continuous distribution in which the probability density varies as a power law near some maximum valueJ 0, we find that ln (t) varies as –t 1/3(lnt)2/3 for large times.  相似文献   
3.
We report here our results on the spectroscopic and elemental analysis of femtosecond (fs) laser-modified regions in polymers of polymethylmethacrylate (PMMA) and polydimethylsiloxane (PDMS) in the context of defect formation and emission in the visible region. Different physical and chemical models are used to explain the changes in modified regions. We found that the emission intensity, recorded from the fs-modified regions of polymers, decreased over time to a constant value. We also demonstrate that these materials are suitable for the preparation of the microstructures en route for light guiding applications. The fs laser-irradiated regions exhibited paramagnetic behavior as was confirmed from electron spin resonance studies through the formation of peroxide-type free radicals. Raman mapping was performed in the modified regions which consisted of defects and found that the modulations in intensity are predominant in the central portion of the structure compared to edges. Elemental analysis has been performed in the modified regions using field emission scanning electron microscope instrument and energy-dispersive X-ray absorption spectroscopy to estimate the percentage contents of individual elements which resulted in defect formation such as paramagnetic and optical centers.  相似文献   
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Particle signals are detected by two parallel measuring chains which consist of a detector and analog to digital converter. We have used OPT101 as photodiode and ADS7870 for A/D converter and the output signal from two parallel measuring chains is processed by on line correlation filter. This filter works as real time systems. A correlation algorithm has been applied for this work. The signal to noise ratio has been increased by applying correlation filter. The gain of the filter has been improved by introducing digital signal processing.  相似文献   
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Abstract

Dichlorotin(IV)trithiophosphates [(RO)P(S)S 2 ]SnCl 2 were prepared by the reaction of methanolic solution of SnCl 4 and dipotassium salt of trithiophosphates in a 1:1 molar ratio and their adducts [(RO)P(S)S 2 ]SnCl 2.N 2 C 12 H 8 and [(RO)P(S)S 2 ]SnCl 2.N 2 C 10 H 8 were prepared by the reaction of methanolic solution of [(RO)P(S)S 2 ]SnCl 2 and N-donor bases in a 1:1 molar ratio. These newly synthesised derivatives have been characterized by elemental analysis; molecular weight measurements; and IR, 13 C, 31 p and 119 Sn NMR spectral studies. Coordination number of four and six was suggested for dichlorotin (IV)trithiophosphates and their adducts with N-donor bases respectively.  相似文献   
10.
The standard molar enthalpy of formation of LaPO4(s), NdPO4(s), and SmPO4(s) has been determined using an isoperibol solution calorimeter. The solution calorimeter vessel was held at 298.15 K. The precipitation reaction between aqueous solution of rare-earth chloride (LnCl3(aq.)) and ammoniacal solution of ammonium dihydrogen phosphate (NH4H2PO4(aq.)) was studied. The temperature of the calorimeter vessel was measured before, during, and after the reaction. The enthalpy change due to precipitation of LaPO4(s), NdPO4(s), or SmPO4(s) from required solutions was measured at 298.15 K. Using these values and other auxiliary data from the literature, thermochemical reaction scheme were devised to calculate the standard enthalpy of formation of each phosphate compound i.e., LaPO4(s), NdPO4(s), and SmPO4(s). The calculated values for LaPO4(s), NdPO4(s), and SmPO4(s) at 298.15 K were found to be ?1947.5 ± 3.2, ?1938.3 ± 3.6, and ?1942.9 ± 3.4 kJ mol?1, respectively.  相似文献   
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