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In this paper, we study the following modified Kirchhoff-type equations of the form: [ABSTRACT FROM AUTHOR]

SUMMARY This study is focused on the analysis of representative thermodynamic cycles for power generation at low-to-medium temperatures (with the highest cycle temperature from 450 to 700 K). The natural working fluid of carbon dioxide is selected for the current tests and comparisons with suitable operation ranges. Energy balance and exergy loss models are established and applied to 10 selected representative thermodynamic cycles. One modified efficiency parameter is also defined for better comparison of performances, which has considered the effects of both specific thermodynamic process and cycle complexity. Based on the modified efficiency parameter, it is found that Rankine cycle yields the highest performance at 450-500 K among the 10 representative cycles, while regenerative Brayton cycle shows better behavior for 550-700 K. Detailed behaviors and optimal principals of regenerative Brayton cycles are also identified and compared in this study. Also, a new cycle is also proposed in this study, which combines the advantages of Rankine cycle and Brayton cycle. The new cycle is proved to have better work output potential but higher system complexity factor. In addition, based on the thermodynamic analysis, possible future directions of low-to-medium temperature power cycles are summarized. It is hoped that the results can be of help for related power generation system designs. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Using the method of exponential dichotomies, we establish a new existence and uniqueness theorem for almost automorphic solutions of differential equations with piecewise constant argument of the form $$\begin{eqnarray*}{x}^{\prime } (t)= A(t)x(t)+ B(t)x(\lfloor t\rfloor )+ f(t), \quad t\in \mathbb{R} ,\end{eqnarray*}$$ where $\lfloor \cdot \rfloor $ denotes the greatest integer function, and $A(t), B(t): \mathbb{R} \rightarrow { \mathbb{R} }^{q\times q} $, $f(t): \mathbb{R} \rightarrow { \mathbb{R} }^{q} $ are all almost automorphic. [ABSTRACT FROM AUTHOR]

High-resolution Fourier transform spectra of trans-acrolein, H2C=C(H)—C(H)=O, have been recorded in the 10 μm region at both room and cooled temperatures on the modified Bomem DA3.002 at the National Research Council of Canada and the Bruker IFS 125HR spectrometer at the far infrared beam line of the Canadian Light Source in Saskatoon. Vibrational fundamentals analyzed so far include the ν11, ν16 and ν14 bands centered at 911.3, 958.7 and 992.7 cm−1 corresponding respectively to the A′ in-plane=CH2-rocking mode, the A″ out-of-plane=CH2-wagging mode, and the A″ wagging mode highly mixed between the ⩾C—H vinyl and ⩾C—H formyl groups [Vibrational mode descriptions are based on Y.N. Panchenko, P. Pulay, F. Török, J. Mol. Spectrosc. 34 (1976) 283–289.] As well, the ν16 + ν18 − ν18 hot band centred at 957.6 cm−1 has been analyzed, where ν18 is the low-frequency (157.9 cm−1) A″ ⩾C—C⪕ torsional mode. The ν11 band is a/b type while the ν16, ν14 and ν16 + ν18 − ν18 bands are c-type. The assigned transitions of each band have been fitted to a Watson asymmetric rotor Hamiltonian, with ground state parameters fixed to values obtained from rotational analyses in the literature. As well, a combined 3-state fit for ν11, ν16 and ν14 was carried out including Coriolis and Z1 constants which account for J and ΔK interactions. Transition dipole moments have been calculated for each of the fundamentals using the ab initio B3LYP method and 6-311++G∗∗ basis set. For the A′ vibrational modes, we have also evaluated transition dipole a- and b-components in the principal axis system from vibrational displacements and dipole moment derivatives. Our ab initio results predict that the ν11 in-plane=CH2 rocking mode has an a-type transition strength about three times greater than the b-type, which is consistent with our observations. Our ab initio force field analysis gives vibrational mode descriptions consistent with previously published work for all 13 A′ modes. However, for the five A″ vibrational modes, our ab initio results disagree with two of the descriptions of Panchenko et al. and three of the descriptions of Hamada et al. [ABSTRACT FROM AUTHOR]

By using the method of the invariant subspaces for unbounded linear operators and Schauder's fixed point theorem, we give an existence theorem of mild pseudo-almost periodic solutions for some semilinear differential equations with a Stepanov-like pseudo-almost periodic term under some suitable assumptions. For this purpose, we show a new composition theorem of Stepanov-like pseudo-almost periodic functions. As applications, we examine the existence of mild pseudo-almost periodic solutions to some second-order hyperbolic equations. Our work is done under a 'uniform continuity' condition instead of the 'Lipschitz' condition assumed in the literature. [ABSTRACT FROM AUTHOR]

Banna viruses (BAVs) have been isolated from pigs, cattle, ticks, mosquitoes, and human encephalitis patients. We isolated and analyzed 20 BAVs newly isolated in China; this finding extends the distribution of BAVs from tropical zone to north temperate climates and demonstrate regional variations in BAV phylogeny and mosquito species possibly involved in BAV transmission. [ABSTRACT FROM AUTHOR]

The article presents a study which investigates the effect of hexavalent chromium (CrVI) on the expression level of apoptosis in the mice liver. It mentions the use of western blot and statistical analysis in the study of healthy male Swiss albino mice which were bought from the Laboratory Animal Center in the Zhejiang Academy of Medical Sciences. Results show that potassium dichromate has the ability to upregulate the protein expression of p53, Bax, cytochrome c and caspase-3 and downregulate the expression of Bcl-2 in the liver of the mice which suggests that p53, Bcl-2, Bax, cytochrome c and caspase-3 are related to the CrVI-induced apoptosis.

The article presents a study which examines the capacity of lead to activate cellular events in the endoplasmic reticulum pathway such as the expressions of C/EBP homology protein (CHOP) and glucose-regulated protein 78 (GRP78) as well as the activation of caspase-12 and calpain. It reveals that lead has increased the expression of GRP78, however, the expression of CHOP and procaspase-12 remained the same. It also shows that caspase-12 and calpain were not activated and that the ultrastructure of endoplasmic reticulum remained unchanged. Hence, it suggests that lead cannot induce apoptosis in PC 12 cells through the endoplasmic reticulum pathway.

The article presents a study on the morphological and biochemical changes linked with apoptosis induced by okadaic acid (OA) in human amniotic FL cells. The study focuses on the determination of the toxic effects of OA in FL cells with relatively lower concentrations and shorter incubation time. Changes in the morphological and biochemical components of FL cells were examined, as cells were induced by OA. Findings on the study show that phosphatidylserine externalization, cytoskeletal disruption, breakage of DNA strand, decreased of Bcl-2 protein experience levels, and PP2A-A subunit protein increase were all associated in the apoptosis of FL cells induced by OA.

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The article discusses a study on the effect of the natural cyanobacterial bloom extract on the expression of proteins in mice. It states that the extract has been administered orally to Imprinting Control Region (ICR) mice for 7 days with different dosages. Western blotting was used to measure the expression level of protein phosphatase 2A (PP2A), B cell lymphoma/leukemia-2 (Bcl-2) and Bcl-2 associated x protein (Bax). Findings show that after 7 days of exposure to the extract, the expression level of PP2A in mice liver tissue was increased significantly between the control and treatment groups, but no significant change on Bcl-2 expression.

The article discusses findings of a study which examines the expression of protein phosphatases 2A (PP2A), CHOP, Bax, Bcl-2, and p53 proteins in microcystin-LR (MCLR)-induced apoptopsis in FL cells. Considered as the most frequently studied, MCLR is also the most toxic in the group of MC. Inhibiting the activity of protein phosphatases 1 (PP1) and 2A (PP2A) is one of the mechanisms of MC toxicity, and this leads to increase of protein phosphorylation which is directly related to their cytotoxic effects and tumor-promoting activity.

Abstract  Reported far-infrared laser lines for five different transition systems of CH3NH2 optically pumped by a CO2 laser have been identified spectroscopically through a high-resolution Fourier transform infrared study of the C-N stretching band together with CO2-laser/microwave-sideband broad-scan and Lamb-dip measurements. From the infrared analysis plus previous far-infrared (FIR) results for the ground vibrational state, quantum numbers have been assigned for seven methylamine FIR laser transitions and their C-N stretching pump absorptions coincident with the CO2 laser lines. The assignments are confirmed through the use of closed frequency combination loops that also provide improved FIR laser frequencies to spectroscopic accuracy. [ABSTRACT FROM AUTHOR]

Tributyltin (TBT) can be transported to the human body by contaminated seafood. Presently, there is no known effective strategy to eliminate TBT's toxic effects from contaminated food. The present study was conducted to investigate the ability of garlic oil (GO) to prevent TBT-induced oxidative damage in vivo as well as in vitro. The results follow: both reactive oxygen species (ROS) production and malondialdehyde content decreased in mice pretreated with GO, the number of cells with damaged DNA in unprotected mice increased significantly compared with that in GO-protected mice (comet assay), and the alleviation of the depletion of cortical thymocytes and damage to nucleoli and mitochondria in GO-protected mice was observed. In human FL (human amniotic cells; American Type Culture Collection) cell studies, TBT-induced intracellular ROS generation was significantly inhibited after FL cells were pretreated with GO, and the TBT-induced cytotoxic effects were also prevented by GO. The results led to the first observation that GO was effective in reducing TBT-induced oxidative damage both in vivo and in vitro. The possible protective mechanism may stem from the considerable ability of GO to scavenge ROS. We conclude that GO could be an effective agent or food supplement in reducing the toxicity of TBT. [ABSTRACT FROM AUTHOR]

In this study, oxidative and DNA damage were measured synchronously after Sprague-Dawley rats were exposed to different dosages of tributyltin (TBT) for 3 and 7 consecutive days. Oxidative damage was measured by analyzing the production of hepatic reactive oxygen species (ROS), the activity of superoxide dismutase (SOD), and the content of malondialdehyde (MDA). DNA damage was measured by single-cell gel electrophoresis (comet assay). After 3 days of exposure, significant differences in ROS production could only be seen between the control and the highest dosage group (10 mg/kg BW d), although after 7 days of treatment, ROS production increased in a dose-dependent manner. SOD activity increased with dosage after 3 days of exposure and decreased with dosage after 7 days of exposure. TBT also induced significant production of MDA after 7 days of exposure. The changes in ROS, SOD, and MDA found in this study suggest that the antioxidative systems of rats were activated by TBT in the first 3 days of exposure but had become exhausted by 7 days of exposure. In the comet assay, the number of cells with damaged DNA in rats treated with TBT increased with dosage of TBT. The most likely mechanism of the DNA breakage induced by TBT is oxidative damage. It can be concluded that exposure of TBT can promote both oxidative and DNA damage in mammals in vivo. [ABSTRACT FROM AUTHOR]