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401.
The ac electrical properties of 5-10% Fe doped polycrystalline sample have been investigated by complex impedance analysis over the frequency and temperature ranges of 1-100 kHz and 77-300 K, respectively. The average normalized change (ΔZ′/Δf)/Z0 has been deduced for these Fe doped CMR samples which shows an increasing trend with iron doping. The most pronounced effect of frequencies is at Tc, with the increase of Fe doping it is observed that not only Tc is lowered substantially but also the height of the peaks of real part of impedance (Z′) is increased which in turn decreases considerably with the increase of the ac field. An equivalent circuit model, Rg(RgbCgb), i.e. a resistor-capacitor network, has been proposed to explain the impedance results at different temperatures. The plot between τ and 1/T gives a straight line from where relaxation time (τ0) has been deduced. The correlated barrier hopping (CBH) model has been employed and the binding energy of the defect states is estimated to be between 0.39 and 0.25 eV while the minimum hoping distance varies within the range of 2.93-5.21 Å for these 5-10% Fe doped LCM samples.  相似文献   
402.

Background  

Serotonin is an important neurotransmitter with wide-ranging functions throughout the central nervous system. There is strong evidence to suggest that regulation of serotonergic gene expression might be related to genetic variability, and several studies have focused on understanding the functional effects of specific polymorphisms within these genes on expression levels. However, the combination of genotype together with gender and brain region could have an overall effect on gene expression. In this study, we report expression patterns of five serotonergic genes (TPH1, TPH2, 5-HT2A, 5-HT2C, 5-HTT) in seven different human post-mortem brain regions (superior frontal gyrus, superior temporal gyrus, striatum, cerebellum, hippocampus, midbrain and thalamus) using TaqMan™ real-time quantitative PCR. In addition, the effect of genotype and gender on their expression levels was determined.  相似文献   
403.
Recently, a traditional remedy (Joshanda) has been replaced largely by modern ready-to-use dosage forms, which have not been compared to the original remedy. Therefore, the present study aimed to compare a number of modern dosage forms with traditional remedy. Seven brands, 3 batches each, were compared with a Lab-made formulation with reference to analytical (proximate analyses, spectroscopic and chromatographic metabolomes) and pharmacological profiles (anti-inflammatory and antibacterial activities). Chemical and pharmacological differences were found between Lab-made Joshanda and modern dosage forms. Such variations were also found within the brands and batches of modern formulations (p < 0.05). The Lab-made Joshanda showed significantly higher pharmacological activities as compared to modern brands (p ). The results of the present study indicate that modern dosage forms are unstandardised and less effective than the traditional remedy. Characteristic profiles obtained from Lab-made Joshanda may be used as reference to produce comparable dosage forms.  相似文献   
404.

This study evaluates a correlation between family history, micronutrients intake, and alternative therapies with genetic instability, before and during breast cancer treatment. For this study, a total of 150 women were selected. Among those, 50 women were breast cancer patients on chemotherapy, while 50 breast cancer patients were on radiotherapy, and 50 were healthy females. All the participants signed the informed consent form and answered the public health questionnaire. Samples of buccal epithelial and peripheral blood cells were collected and analyzed through micronucleus and comet assays. The cells were evaluated for apoptosis and DNA damage. Results showed the association of patients’ family history with an increase in toxicogenetic damage before and during cancer therapy. On the other hand, patients with late-onset cancer also presented genetic instability before and during therapy, along with those who did not take sufficient vegetables and alternative therapies. A positive correlation was observed between the genetic instability and alternative therapies, while inverse correlation was recorded with the vegetable consumption. Results clearly explain that the nutritional aspects and alternative therapies influence the genetic instability before and during cancer therapies especially in radiotherapy treated patients. Our data could be used for the monitoring therapies and management of breast cancer patients.

  相似文献   
405.
In the present investigation, we have studied the effects of mixed convection heat and mass transfer on peristaltic flow of Williamson fluid model in a vertical annulus. The governing equations of Williamson fluid model are simplified using the assumptions of long wavelength and low Reynold’s number. An approximated analytical and numerical solutions are found for the velocity field using (i) Perturbation method (ii) Shooting method. The comparisons of analytical and numerical solutions have been presented. The expressions for pressure rise, velocity against various physical parameter are discussed through graphs.  相似文献   
406.
The flow of an Oldroyd 8-constant fluid between coaxial cylinders with variable viscosity is considered. The heat transfer analysis is also taken into account. An analytical solution of the non-linear problem is obtained using homotopy analysis method. The behavior of pertinent parameters is analyzed and depicted through graphs.  相似文献   
407.
In the present investigation we have studied the combined heat and mass transfer effects on the peristaltic flow of non-Newtonian fluid. The governing equations are simplified under the assumptions of longwave length low Reynold’s number approximation. The resulting highly nonlinear equations are solved analytically and numerically. At the end the numerical results are discussed pictorially for various emerging parameters of interest.  相似文献   
408.
This study explores the effects of heat transfer on the Williamson fluid over a porous exponentially stretching surface. The boundary layer equations of the Williamson fluid model for two dimensional flow with heat transfer are presented. Two cases of heat transfer are considered, i.e., the prescribed exponential order surface temperature (PEST) case and the prescribed exponential order heat flux (PEHF) case. The highly nonlinear partial differential equations are simplified with suitable similar and non-similar variables, and finally are solved analytically with the help of the optimal homotopy analysis method (OHAM). The optimal convergence control parameters are obtained, and the physical fea- tures of the flow parameters are analyzed through graphs and tables. The skin friction and wall temperature gradient are calculated.  相似文献   
409.
A simulation study of lateral current injection 1.55 m laser with strain-compensated multiple quantum-well (MQW) active region (InGaAsP well, InGaAlAs barrier) is presented using self-consistent 2D numerical simulations. The effects of different mesa width and p-doping in the QWs on the carrier and gain uniformity across the active region are explored. A high p-doping in the quantum wells is found to increases the carrier and gain non-uniformity across the active region. The QW region close to the n-contact side does not provide much gain at high optical powers. An asymmetric optical waveguide design is proposed to help reduce the gain non-uniformity across the active region. By shifting the optical modal peak toward the p-side, the modal overlap between the gain region and the optical mode is improved and a more even carrier and gain distribution is obtained. However, due to reduced bandgap of the quaternary InGaAsP p-cladding, an enhanced electron leakage out of the QWs into the p-cladding degrades the laser efficiency and increases the threshold current. Transient time–domain simulations are also performed to determine the small-signal modulation response of the laser promising a simulated high modulation bandwidth suitable for direct-modulation applications.  相似文献   
410.
Odd parity autoionizing Rydberg levels of atomic lead in the energy region above the 6p1/2 ionization threshold have been investigated using three-step laser excitation in conjunction with an atomic beam apparatus. The 6p3/2ns (J = 1, 2), 6p3/2nd (J = 1, 2, 3) and 6p3/2ng (J = 2, 3) levels have been observed from the 6p5f 1/2[5/2]2 intermediate level. Energy values and FWHM of forty levels belonging to the 6p3/2ns, 6p3/2nd and 6p3/2ng configurations are presented. Six levels based on the 6p3/2ng (5, 13 n 15) configurations and three levels attached to the 6p3/28d configuration are reported for the first time. The present study of the low-lying autoionizing levels attached to the 6p3/25g (J = 2, 3) configuration completes the series adjacent to the 6p1/2 limit.  相似文献   
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