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A transition metal-free, visible light-induced intramolecular oxidative cylclization–detosylation–aromatization was discovered. This photocatalytic strategy generated potentially bioactive indolo[2,3-b]-quinoline derivatives in up to 97% yield. With a simple setup, this protocol works efficiently under mild conditions. The final products were obtained both in the presence and in the absence of Eosin Y sodium salt, but the reaction efficiency was largely improved with the use of a photosensitizer. [ABSTRACT FROM AUTHOR]

The interactions between the large and small scales of turbulence in compressible turbulent mixing layers are investigated by means of direct numerical simulation of the compressible Navier–Stokes equations. Two typical cases with the convective Mach numbers Mc = 0.3 and 1.6 are considered to reveal the influence of compressibility on the scale interactions. The velocity signals are decomposed into large-scale and small-scale ones based on the Taylor length scale for the analysis of scale interactions and split into solenoidal and compressive parts for the investigation of compressibility effect. It is found that the small scales are modulated by the large-scale velocity fluctuations with different properties on both sides of the mixing layer, and the large-scale modulation on the small scales is reduced with increase in the convective Mach number. The interaction between the large-scale compressive velocity fluctuations and the small scales is mainly associated with absolute values of the large-scale compressive velocity fluctuations and is independent of transverse position of the mixing layer. The large-scale compressive velocity fluctuations increase with the solenoidal counterparts. [ABSTRACT FROM AUTHOR]

The complex thermal-hydraulic-mechanical (THM) coupling is the key issue to the energy extraction from a geothermal reservoir, where fractures are the main channels for fluid circulation and heat transfer. However, the effects of matrix deformation-induced aperture variation and fracture roughness on heat recovery efficiency are unclear. In this paper, a fully coupling THM model based on a discrete fracture network is proposed to explore these coupling effects. First, the fracture roughness and the fracture aperture variation with effective stress are introduced. Second, the water flow and heat transfer in the matrix and fractures as well as the deformation of the geothermal reservoir are individually formulated for a fractured geothermal reservoir. Third, the model is validated with analytical solution for its thermal-hydraulic (TH) coupling effect and literature data for its hydraulic-mechanical (HM) coupling effect. Finally, the features of heat transfer and fluid flow in the fractured geothermal reservoir are comparatively analyzed through four scenarios. The simulation results indicate that the discrete fracture network severely impacts the pressure distribution and temperature advance. The aperture variation induced by solid deformation can enhance heat transfer efficiency, and the fracture roughness can reduce the heat transfer efficiency. [ABSTRACT FROM AUTHOR]

The coupling of heat transfer and water flow in rock fractures is a key issue to geothermal energy extraction. However, this coupling in a rough fracture has not been well studied so far. This paper will study this coupling in a rock fracture with different roughness. First, multi-scale and self-affine rough fracture are constructed through the Weierstrass–Mandelbrot function and embedded into a rock block. Its single scale trend line is also derived. Second, a roughness factor is proposed based on the standard deviation of each segment from the trend line and introduced into the governing equation of fracture flow. After coupling with heat transfer and matrix deformation, a thermal-hydro-mechanical (THM) coupling model is formulated for a rough fracture flow. Third, an analytical solution is derived through the Laplace transform and Stehfest method and used for the validation of this THM coupling model. Finally, the effects of fracture roughness and matrix deformation on heat transfer and fracture flow are numerically investigated. The simulation results indicate that the rock fracture with lower fractal dimension has higher heat transfer efficiency. The effect of fracture roughness on heat transfer is much greater than that of aperture variation induced by the shrinkage of rock matrix. [ABSTRACT FROM AUTHOR]

Previous studies ignore the evolutions of pore microstructure parameters (pore diameter fractal dimension D λ and tortuosity fractal dimension D τ p ) but these evolutions may significantly impact the gas transport during gas extraction. In order to investigate these evolutions of fractal dimension properties during gas extraction, following four aspects are studied. Firstly, surface diffusion in adsorbed multilayer is modeled for fractal shale matrix. Our new matrix permeability model considers the slip flow, Knudsen diffusion and surface diffusion. This model is verified by experimental data. Secondly, a new fracture permeability model is proposed based on fractal theory and the coupling of viscous flow and Knudsen diffusion. Thirdly, the multilayer adsorption and these permeability models are introduced into the equations of gas flow and reservoir deformation. Finally, sensitivity analysis is performed to determine the key factors on fractal dimension evolution. The results show that the multilayer adsorption can accurately describe the adsorption properties of real shale reservoir. Shale reservoir deformation and gas desorption govern the evolutions of fractal dimensions. The multilayer adsorption and adsorbed gas porosity ϕ a play an important role in the evolutions of fractal dimensions during gas extraction. The monolayer saturated adsorption volume V m is the most sensitive parameter affecting the evolution of fractal dimensions. Therefore, the effects of gas adsorption on the evolution of fractal dimensions cannot be neglected in shale reservoirs. [ABSTRACT FROM AUTHOR]

Previous studies on hydraulic fracturing mainly focus on the effects of the in-situ stress state, permeability, fracturing fluids, and approach angle in homogeneous rocks, but the impacts of joint mechanical properties in laminated shale reservoirs on the propagation and formation of the fracture network are still unclear. In this study, a coupled fluid-mechanical model was developed to investigate the impacts of joint mechanical properties on hydraulic fracture propagation. Then, this model was validated with Blanton's criterion and some experimental observations on fracture morphology. Finally, a series of numerical simulations were conducted to comparatively analyze the impacts of joint mechanical properties on the total crack number, the percentage and distribution of each fracture type, the process of crack propagation, and the final fracture morphology. Numerical results show that the cracking behaviors induced by joint mechanical properties vary with the approach angle. Joint strength has a significant influence on the generation of matrix tensile cracks. The tensile-to-shear strength ratio plays an even more important role in the shear slips of bedding planes and is conducive to the formation of complex fracture morphology. [ABSTRACT FROM AUTHOR]

Using density functional theory, we investigate the structure of the double water bilayer with or without coadsorption of CO on Pt(111). The double water bilayer consists of two bilayers. Each bilayer is buckled with every second water molecule being closer to the surface than every other water molecule. CO is found to adsorb most strongly when substituting in the first bilayer, the water molecule closest to the surface. Dissociation of H2O in the water bilayer (with or without CO) is further considered. A great number of pathways for the dissociation are studied. These include homolytic pathways where both dissociation products end up adsorbed on the Pt surface and heterolytic pathways where only the OH is adsorbed, while a proton is transferred to the water adlayers. We find that the heterolytic dissociation pathways are energetically more favorable than the homolytic ones, yet they are all rather endothermic. The most favorable pathways found have reaction energies of 0.60 and 0.52 eV without and with CO present. The corresponding activation energies are 0.99 and 0.53 eV, respectively. [ABSTRACT FROM AUTHOR]

The governing equations of a two-phase flow have a strong nonlinear term due to the interactions between gas and water such as capillary pressure, water saturation, and gas solubility. This nonlinearity is usually ignored or approximated in order to obtain analytical solutions. The impact of such ignorance on the accuracy of solutions has not been clear so far. This study seeks analytical solutions without ignoring this nonlinear term. Firstly, a nonlinear mathematical model is developed for the two-phase flow of gas and water during shale gas production. This model also considers the effects of gas solubility in water. Then, iterative analytical solutions for pore pressures and production rates of gas and water are derived by the combination of travelling wave and variational iteration methods. Thirdly, the convergence and accuracy of the solutions are checked through history matching of two sets of gas production data: a China shale gas reservoir and a horizontal Barnett shale well. Finally, the effects of the nonlinear term, shale gas solubility, and entry capillary pressure on the shale gas production rate are investigated. It is found that these iterative analytical solutions can be convergent within 2-3 iterations. The solutions can well describe the production rates of both gas and water. The nonlinear term can significantly affect the forecast of shale gas production in both the short term and the long term. Entry capillary pressure and shale gas solubility in water can also affect shale gas production rates of shale gas and water. These analytical solutions can be used for the fast calculation of the production rates of both shale gas and water in the two-phase flow stage. [ABSTRACT FROM AUTHOR]

Water permeation into a porous medium is a common but important phenomenon in many engineering fields such as hydraulic fracturing. The water permeation front moves with time and may significantly impact the field variable evolution near the water front. Many algorithms have been developed to calculate this water front motion, but few numerical algorithms have been available to calculate the water front motion in anisotropic fluid-solid couplings with high computational efficiency. In this study, a numerical model is proposed to investigate the front motion of water permeation into an anisotropic porous medium. This model fully couples the mechanical deformation, fluid flow, and water front motion. The water front motion is calculated based on a directional Darcy's flow in the anisotropic porous medium, and a revised formula with a correction coefficient is developed for the estimation of permeation depth. After verification with three sets of experimental data, this model is used to numerically investigate the impacts of permeability, viscosity, permeability anisotropy, and mechanical anisotropy on water front motion. Numerical results show that the proposed model can well describe the anisotropic water permeation process with reasonable accuracy. The permeation depth increases with permeability, mobility, and mechanical anisotropy but decreases with viscosity and permeability anisotropy. The correction coefficient mainly depends on porosity evolution, flow pattern, mobility, permeability anisotropy, and mechanical anisotropy. [ABSTRACT FROM AUTHOR]

A multiple fractured shale gas reservoir is divided into three zones, namely the single-porosity zone, the dual-porosity zone, and the hydraulic fracture zone. The distributions of pore size, fracture length, and fracture aperture vary in each zone and affect shale gas productivity. This paper developed a fractal numerical model to investigate the impacts of zone fractal properties on the shale gas productivity of a multiple fractured horizontal well. In this model, a fractal permeability model was developed, in which the diameter/aperture distribution of circular/slit pores and the length of fractures all follow fractal scaling law. This numerical model was solved by finite element method within the platform of COMSOL Multiphysics and verified through the history matching of production data from the Marcellus and Barnett shale reservoirs. Finally, the effects of the fractal dimension ( D e , D l , D τ ) and the maximum diameter ( e max ) of the pores on gas productivity (measured by gas production rate and cumulative gas production) were investigated. Numerical results show that increasing the maximum pore diameter e max can enhance gas productivity, but increasing the pore diameter fractal dimension D e makes the gas productivity decrease and increasing tortuous fractal dimension D τ decreases the gas productivity, too. The length fractal dimension D l of fractures is sensitive to the gas flow in the dual-porosity zone. [ABSTRACT FROM AUTHOR]

A shale gas reservoir is usually hydraulically fractured to enhance its gas production. When the injection of water-based fracturing fluid is stopped, a two-phase flowback is observed at the wellbore of the shale gas reservoir. So far, how this water production affects the long-term gas recovery of this fractured shale gas reservoir has not been clear. In this paper, a two-phase flowback model is developed with multiscale diffusion mechanisms. First, a fractured gas reservoir is divided into three zones: naturally fractured zone or matrix (zone 1), stimulated reservoir volume (SRV) or fractured zone (zone 2), and hydraulic fractures (zone 3). Second, a dual-porosity model is applied to zones 1 and 2, and the macroscale two-phase flow flowback is formulated in the fracture network in zones 2 and 3. Third, the gas exchange between fractures (fracture network) and matrix in zones 1 and 2 is described by a diffusion process. The interactions between microscale gas diffusion in matrix and macroscale flow in fracture network are incorporated in zones 1 and 2. This model is validated by two sets of field data. Finally, parametric study is conducted to explore key parameters which affect the short-term and long-term gas productions. It is found that the two-phase flowback and the flow consistency between matrix and fracture network have significant influences on cumulative gas production. The multiscale diffusion mechanisms in different zones should be carefully considered in the flowback model. [ABSTRACT FROM AUTHOR]

An analytical solution is developed for the shale gas productivity of a multiple-fractured horizontal well based on a diffusion model and a trilinear flow pattern. The shale gas reservoir is divided into three flow regions: hydraulic-fracture region, micro-fracture network or dual-porosity region, and pure-matrix region. For the pure-matrix region, a transient diffusion equation is solved based on our previous diffusivity model developed for the shale matrix. For the micro-fracture network region, a modified dual-porosity model is proposed wherein both the free and adsorbed gases in the shale matrix flow into the micro-fracture network through a pseudo-steady diffusion process. These gases then form conflux at the hydraulic fractures and continue to the wellbore. A dimensionless solution is obtained for the bottom-hole pressure in the Laplace domain considering the skin effect. An analytical solution is obtained for the gas production rate in a real-time domain through a partial Taylor series simplification and Laplace inverse transform. This analytical solution is compared with the field data of the shale gas produced from a fractured horizontal well located in southwestern China, and a good agreement is observed. Finally, a parametric study is conducted to quantify the effects of key parameters on the gas production rate. The parameters include the bottom-hole pressure, half-length of the hydraulic fracture, permeability of the hydraulic fracture, block size of the shale matrix, and pore size within the shale matrix. These results show that the analytical solution can be used to estimate the enhancement of the shale gas recovery through hydraulic fracturing. [ABSTRACT FROM AUTHOR]

1α-Hydroxycholecalciferol (1α-OH-D3) is a vitamin D derivative. The objective of this study was to evaluate the effects of 1α-OH-D3 on the growth and the mRNA expression of vitamin D receptor (VDR) in the small intestine and kidney of chickens. A total of 240 males of one-day-old Ross 308 broilers was randomly assigned to 4 treatments with 5 replicates of 12 birds per replicate. Three levels of 1α-OH-D3 (1.25, 2.5, and 5 µg/kg) were added to a basal diet containing 0.50% calcium (Ca), 0.25% non-phytate phosphorus (NPP), and without supplemental cholecalciferol (vitamin D3). The control diet contained 1.00% Ca, 0.45% NPP, and 25 µg/kg cholecalciferol. Dietary 1α-OH-D3 levels linearly improved the average daily feed intake (ADFI), average daily gain (ADG), femur and tibia mineralization, and plasma Ca concentration, and retained Ca and total phosphorus (tP) amounts in broilers from 1 to 21 d of age (P < 0.05). In addition, 1α-OH-D3 also linearly up-regulated the mRNA expression levels of VDR in the duodenum as well as those of VDR and sodium-phosphate cotransporter NaPi-IIa and NaPi-IIc in the kidney of broilers (P < 0.05). However, 1α-OH-D3 did not affect the mRNA levels of 25-hydroxylase in the liver or NaPi-IIb in the duodenum (P > 0.05). No differences were observed in the ADFI, ADG, bone length, plasma mineral concentration, retained tP amount, or the mRNA levels of the above genes (except for VDR in the kidney) between the birds fed the diet with 5 µg/kg 1α-OH-D3 and the birds fed the control diet (P > 0.05). By contrast, the weight, ash weight, ash percentage, and Ca percentage of the bone, retained Ca amount, and the mRNA level of VDR in the kidney were lower in the birds fed the diet with 5 µg/kg 1α-OH-D3 than in the birds fed the control diet (P < 0.05). These data indicate that 1α-OH-D3 up-regulates the gene expression of VDR in the small intestine and kidney at the transcriptional level, thereby improving the growth performance and bone mineralization of broiler chickens from 1 to 21 d of age. [ABSTRACT FROM AUTHOR]

Negative energy balance is considered as the pathological basis of energy metabolic disorders in periparturient dairy cows. Serum non-esterified fatty acids ( NEFA) are one of the most important indicators of energy balance status. Fibroblast growth factor 21 ( FGF21) has been identified as a hepatokine involved in regulation of metabolic adaptations, such as promoting hepatic lipid oxidation and ketogenesis, during energy deprivation. However, the direct effects of NEFA on FGF21 expression and secretion in bovine hepatocytes are not entirely clear. The objective of this study was to investigate the effects of different NEFA concentrations on FGF21 expression and secretion in calf hepatocytes cultured in vitro. NEFA were added to the culture solution at final concentrations of 0.6, 1.2, 1.8 and 2.4 mmol/L. After 24 hr of continuous culture, FGF21 mRNA and protein expression levels in the hepatocytes were determined by real-time PCR and Western blot respectively. FGF21 secretion in the supernatant was determined by enzyme-linked immunosorbent assay ( ELISA). The results showed that expression and secretion of FGF21 at 0.6 mmol/L NEFA-treated hepatocytes was higher than that of the control group ( p < .05). The FGF21 expression and secretion were similar at 1.2, 1.8 and 2.4 mmol/L NEFA-treated hepatocytes and significantly higher than those observed for controls ( p < .01). These data suggest that high concentrations of NEFA significantly promote FGF21 expression and secretion in bovine hepatocytes. In particular, this promotion occurs in a dose-dependent manner and may be involved in the pathological processes of energy metabolism disorders of dairy cows in the peripartum period. [ABSTRACT FROM AUTHOR]

We theoretically investigate the propagation properties of cosh-Airy beams, which can be considered as a superposition of two Airy beams with different decay factors. We find that the field distribution of cosh-Airy beams is the same as that of Airy beams. Moreover, we find that the evolution of cosh-Airy beams is determined by the parameters of the cosh modulation function, in addition to the transverse scale factor and decay factor of the Airy beams. Our results demonstrate a possible method of manipulating Airy beams in free space. They can also be extended to the study of the propagation properties of cosine-Airy beams (or sine-Airy beams). [ABSTRACT FROM PUBLISHER]

We investigate the propagation of an Airy beam along the optical axis of a uniaxial medium, and we find that the propagation property of the Airy beam is determined by the ordinary refractive index of uniaxial crystals and is independent of the ratio of the extraordinary to ordinary refractive index. We also know that the polarization state of linearly polarized Airy beams changes gradually during the propagation. This shows that the propagation properties of the Airy beam in uniaxial crystals along the optical axis is distinctly different from that orthogonal to the optical axis. [ABSTRACT FROM PUBLISHER]

To explore the effects of maggot antimicrobial peptide treatment of Salmonella pullorum-infected chickens on the mRNA expression levels of TGF-β4 and TNF-α in small intestinal mucosa, the duodenum, jejunum and ileum mucosa were isolated 3, 5 and 7 days after induced AMP, non-induced AMP, antibiotics or maggot treatment and the TGF-β4 and TNF-α mRNA expression was evaluated by quantitative real-time PCR. We found that mRNA of TGF-β4 was highly expressed in the duodenum, jejunum, and ileum when Salmonella pulloruminfected chickens were treated with antibiotics, non-induced AMP, and AMP, respectively (P<0.001). Similarly, TNF-α mRNA was highly expressed in the duodenum and jejunum when Salmonella pullorum-infected chickens were treated with induced AMP and maggots, respectively (P<0.001), and the expression of TNF-α mRNA was higher in response to the use of induced AMP than antibiotics on day 5 after treatment (P<0.05). Therefore, maggot AMP functional efficiency, along with evaluation of TGF-β4 and TNF-α produced by small intestinal mucosa, may be useful for the prevention and treatment of Salmonella pullorum when developing new chicken feed additives. [ABSTRACT FROM AUTHOR]

The photoionization of hydrogen-like ions in n ⩽ 3 bound states, embedded in cold, dense quantum plasmas, is investigated in detail. The electron energies and wave functions for the bound and continuum states are determined by numerically solving the scaled Schrödinger equation by the fourth-order symplectic integration scheme. The monotonic behavior of the photoionization cross section for a pure Coulomb potential is dramatically changed due to the plasma screening effects described by the cosine-Debye-Hückel potential. In the region of low photoelectron energies, the photoionization cross section, besides the usual Wigner-law threshold behavior, exhibits a rich structure of shape and virtual-state resonances when the plasma screening parameter takes values around the critical screening parameter for which a bound state enters the continuum. It is observed that a shape resonance is followed by a Cooper minimum in the photoionization cross section when the principal quantum number of continuum quasi-bound state is equal to the one of the initial bound states. [ABSTRACT FROM AUTHOR]

As the most fundamental deformation mechanism in metallic glasses (MGs), the shear banding has attracted a lot of attention and interest over the years. However, the intrinsic properties of the shear band are affected and even substantially changed by the influence of non-rigid testing machine that cannot be completely removed in real compression tests. In particular, the duration of the shear banding event is prolonged due to the recovery of the stressed compliant frame of testing machine and therefore the temperature rise at the operating shear band is, more or less, underestimated in previous literatures. In this study, we propose a model for the ‘ideal’ shear banding in metallic glass. The compliance of the testing machine is eliminated, and the intrinsic shear banding process is extracted and investigated. Two important physical parameters, the sliding speed and the temperature of shear band, are calculated and analysed on the basis of the thermo-mechanical coupling. Strain-rate hardening is proposed to compensate thermal softening and stabilise the shear band. The maximum value of the sliding speed is found to be on the order of 10 m/s at least, and the critical temperature at which strain-rate hardening begins to take effect should reach as high as 0.9Tg(Tgis the glass transition temperature) for a stable shear banding event in metallic glass according to the early experimental data. This model can help to understand and control the shear banding and therefore the deformation in MGs. [ABSTRACT FROM PUBLISHER]

Presents a study that prepared superconducting fibers and wires through spray pyrolysis of metal nitrate precursors on a commercial carbon fiber substrate, followed by heating in air and annealing in oxygen [sub2]. Details on approaches such as x-ray diffraction and scanning electron microscopy used to characterize the fibers; Use of carbon as the substrate for spray pyrolysis; Advantages offered by carbon substrates.

Utilizing a simplified quantum model approach, the low-energy inelastic collision processes between yttrium atoms (ions) and hydrogen atoms have been studied. Rate coefficients corresponding to the mutual neutralization, ion-pair formation, excitation, and de-excitation processes for the above collision systems have been provided in the temperature range of 1000–10 000 K. Three ionic states and 73 covalent states are considered in calculations for the collisions of yttrium atoms with hydrogen atoms, which include six molecular symmetries and 4074 partial inelastic reaction processes. For the collisions of yttrium ions with hydrogen atoms, one ionic state and 116 covalent states are included, which are related to three molecular symmetries and 13 572 partial inelastic collision processes. It is found that the rate coefficients for the mutual neutralization process have a maximum at T = 6000 K, which is an order of magnitude higher than those of other processes. Notably, the positions of optimal windows for the collisions of yttrium atoms and ions with hydrogen atoms are found near electronic binding energy −2 eV (Y) and −4.4 eV (Y+), respectively. The scattering channels located in or near these optimal windows have intermediate-to-large rate coefficients (greater than 10−12 cm3 s−1). The reported data should be useful in the study of non-local thermodynamic equilibrium modelling. [ABSTRACT FROM AUTHOR]

Elastic scattering of electrons on a finite-temperature quantum screened potential is studied by using the partial wave decomposition of scattering wavefunction. The influence of plasma temperature on the total and l = 0, 1, and 2 partial wave cross sections is systematically analyzed in the present work. It is found that when the plasma density is fixed, the screened strength does not change monotonically with temperature, which leads to different conditions for forming shape resonance in the scattering cross sections for the different temperature domains. The scattering cross sections under the environments of low temperature limit are compared with those for zero-temperature quantum plasmas. [ABSTRACT FROM AUTHOR]

The properties of bound-bound transitions in hydrogen-like ions in dense quantum plasmas, characterized by a cosine-Debye-Huckel interaction between charged particles, are studied in detail. The transition frequencies, oscillator strengths, and radiative transition probabilities of Lyman and Balmer series are calculated for a wide range of screening strengths of the interaction up to the n = 5 shell. For An = 0 transitions, all these quantities exhibit a significant decrease with increasing screening strength, while for the An = 0 transitions and for the radiative lifetimes, the opposite is true. The present results are compared with those available from the literature. They are also compared with the results for the pure Debye-Huckel potential with the same screening strength. [ABSTRACT FROM AUTHOR]

In this study, the polymerisation effects of four microsatellites (OarAE101, BM1329, BM143 and LSCV043) on litter size in Xinong Saanen goats were analysed by means of microsatellite marker and pedigrees, then associations between combined genotypes and litter size were performed. The results indicate that the individuals with A5A1B10B5C5C1D6D2 (3.10 ± 0.07) had greater litter sizes than those with other combined genotypes in terms of average parity (P < 0.05). Comparing A5A1B10B5C5C1D6D2 with A7A2B10B5C5C1D6D2, the polymerisation effect value of the A5A1 genotype litter size was 18.09% higher than that of the A7A2 genotype. Comparing A5A1B6B1C6C1D6D2 of the F1 generation with A5A1B6B1C7C3D6D2 of the F2 generation, it was shown that the polymerisation effect value of the C6C1 genotype was 37.93% higher than that of the C7C3 genotype. Comparing A5A1B6B1C8C4D4D1 of the F1 generation with A5A1B6B1C8C4D9D5 of the F2 generation, it was shown that the polymerisation effect value of the D4D1 genotype was 68.07% higher than that of the D9D5 genotype. These results suggested that A5A1B10B5C5C1D6D2 is a useful marker affecting caprine litter size. In the goat industry, litter size is extremely important. Polymerisation effects of four microsatellites (OarAE101, BM1329, BM143 and LSCV043) significantly affected litter size of goats. The four microsatellites could serve as a genetic marker for litter size in goat breeding. [ABSTRACT FROM AUTHOR]

CO2 leakage through the caprock of a CO2 sequestration site to the groundwater system is an important topic in the field of geo-environmental engineering. This problem can be described by a fully coupled model among the two-phase flow, caprock deformation, gas diffusion and CO2 sorption. The main purpose of this paper is to present such a model for investigating the caprock sealing efficiency. Firstly, a conceptual model is proposed for the flow in a composite body consisting of the fracture network and shale matrix. In this model, two-phase flow of brine water and CO2 is observed only in the fracture network but the CO2 in the fractures further diffuses into shale matrix through a much slower diffusion process. This diffusion process makes shale matrix swell/shrink through CO2 sorption and significantly alters the porosity and permeability of the fracture network. The interaction between the CO2-brine flow and shales induces shale deformation and modifies the sorptive chemistry of the shale matrix. Then, this conceptual model is formulated by the partial differential equations and full coupling of those processes, thus forming a fully coupled mathematical model. Finally, this fully coupled mathematical model is applied to a caprock layer to investigate the combined effects of two-phase flow, shale deformation, gas diffusion and CO2 sorption on the caprock sealing efficiency. The mechanism for self-enhancing or self-limiting in the CO2-brine mixing zone is explored. It is also applied to a caprock layer embedded a vertical fracture and the CO2 migration in the storage space. These examples demonstrate that this model is able to numerically simulate the CO2 storage relevant geological systems. This work may enrich the contents of the emerging computational geoscience discipline through geoscience modeling. [ABSTRACT FROM AUTHOR]

The relativistic effects in the photoionization of hydrogen-like ion with screened Coulomb interaction of Yukawa type are studied for a broad range of screening lengths and photoelectron energies. The bound and continuum wave functions have been determined by solving the Dirac equation. The study is focused on the relativistic effects manifested in the characteristic features of photoionization cross section for electric dipole nl → ε,l±1 transitions: shape resonances, Cooper minima and cross section enhancements due to near-zero-energy states. It is shown that the main source of relativistic effects in these cross section features is the fine-structure splitting of bound state energy levels. The relativistic effects are studied in the photoionization of Fe25+ ion, as an example. [ABSTRACT FROM AUTHOR]

As a main stream of waste from the paper and pulp industry, paper sludge is regarded as a threat to environmental safety as most of it is disposed via landfill or incineration, which can cause severe soil, water or air pollution. However, alkaline paper sludge has the potential to be a catalyst in biomass pretreatment, and also contains a large amount of fiber that can be used as a feedstock for ethanol production. The dissolved lignin in alkaline pretreatment can be recovered as a good quality co-product such as lignin pellets. The ash in paper sludge can also be recovered to replace sand as a raw material in mortar production. However, the use of paper sludge for commercialized ethanol production is currently a challenge due to its low solid content and high pH. This paper therefore proposes a novel conceptual design for combining paper sludge and agricultural residues (e.g. rice straw in this study) to produce ethanol and other co-products. The net present value is used to assess the economic potential of two proposed process designs: (1) a current technology of turning C5 sugars into biogas; and (2) a prospective technology of co-fermenting both C5 and C6 sugars into ethanol. It is found that both approaches could be economically feasible, but at different scales of production. A sensitivity analysis is also conducted to investigate the effects of plant size, feedstock stream composition (the ratio between rice straw and paper sludge) and subsidies on the economic performance of the proposed projects. [ABSTRACT FROM AUTHOR]

Chronic wounds are a major burden for worldwide health care systems, and patients suffer pain and discomfort from this type of wound. Recently gas plasmas have been shown to safely speed chronic wounds healing. In this paper, we develop a deterministic mathematical model formulated by eight-species reaction-diffusion equations, and use it to analyze the plasma treatment process. The model follows spatial and temporal concentration within the wound of oxygen, chemoattractants, capillary sprouts, blood vessels, fibroblasts, extracellular matrix material, nitric oxide (NO), and inflammatory cell. Two effects of plasma, increasing NO concentration and reducing bacteria load, are considered in this model. The plasma treatment decreases the complete healing time from 25 days (normal wound healing) to 17 days, and the contributions of increasing NO concentration and reducing bacteria load are about 1/4 and 3/4, respectively. Increasing plasma treatment frequency from twice to three times per day accelerates healing process. Finally, the response of chronic wounds of different etiologies to treatment with gas plasmas is analyzed. [ABSTRACT FROM AUTHOR]

Two kinds of floating electrode, floating dielectric barrier covered electrode (FDBCE) and floating pin electrode (FPE), which can enhance the performance of plasma jet are reported. The intense discharge between the floating electrode and power electrode decreased the voltage to trigger the plasma jet substantially. The transition of plasma bullet from ring shape to disk shape in the high helium concentration region happened when the floating electrode was totally inside the powered ring electrode. The enhanced electric field between propagating plasma bullet and ground electrode is the reason for this transition. The double plasma bullets happened when part of the FDBCE was outside the powered ring electrode, which is attributed to the structure and surface charge of FDBCE. As part of the FPE was outside the powered ring electrode, the return stroke resulted in a single intensified plasma channel between FPE and ground electrode. [ABSTRACT FROM AUTHOR]

This paper on three heteroleptic {(bpy)2Ru[2-(perylen-3-yl)-1-H-imidazo[4,5-f][1,10]-phenanthroline)]}2+, {(bpy)2Ru[2-(pyren-1-yl)-1-H-imidazo[4,5-f][1,10]phenanthroline]}2+ and {(bpy)2Ru[2-(anthracen-10-yl)-1-H-imidazo[4,5-f][1,10]phenanthroline]}2+ complexes with perylene, pyrene and anthracene appended 1-H-imidazo[4,5-f][1,10]-phenanthroline as the diimine ligands is a further demonstration of the effect of extending the diimine ligands' π-system on the absorption and emission properties. [ABSTRACT FROM AUTHOR]

Abstract: A single band belonging to the band system has been rotationally analyzed for each of the two isotopologues, BaOH and BaOD, using high-resolution V-type optical–optical double resonance spectroscopy. BaOH and BaOD molecules were synthesized in a Broida-type oven. High-resolution spectra were recorded by monitoring the dip in fluorescence of the transition excited by a single-mode ring dye laser (pump laser), whilst a single-mode Ti:Sapphire laser scanned the corresponding transition. The observed spectra resemble a typical transition, believed to emanate from single or triple quanta of the bending vibration in the state. Measured rotational lines have been assigned and rotational and fine structure parameters determined through a combined least-squares fit with the millimeter-wave pure rotational data of the state. Previous analyses of the transitions of BaOH and BaOD yielded significantly different spin–orbit coupling constants, which were attributed to possible global and local perturbations arising from vibrationally-excited bands of the state. Although the newly observed state bands have not been conclusively assigned a specific spin state, the derived Ω-doubling constants show significant character, further indicating strong interactions between the and states of BaOH. To validate these conclusions, ab initio calculations have been carried out to further understand the nature of the BaOH excited states. The , , , , , and states have been characterized by means of multireference configuration interaction calculations using the MOLPRO software. Calculated vertical term energies show relatively good agreement with existing optical data. [Copyright &y& Elsevier]

Infection of a Myxobolus species, previously identified as Myxobolus rotundus, was detected in 182 of 7892 (2.31%) allogynogenetic gibel carp, Carassius auratus gibelio, in a closed pond culture system in China. Morphological and molecular data showed that this myxosporean is a different species from M. rotundus parasitizing Abramis brama in Europe and is thus designated as a new species, Myxobolus turpisrotundus. M. rotundus (s.l.) ex C. auratus auratus is a synonym of M. turpisrotundus. Plasmodia of M. turpisrotundus develop in the subepidermal tissues of the body surface resulting in an unaesthetic appearance and causing severe economic losses. Prevalence of infection with the myxosporean plasmodia varied seasonally, increasing in winter and decreasing in spring. Prevalence was positively correlated to host size, but no host sex-specificity was found. No infection was observed in other fish species (grass carp, bighead carp and yellow catfish) reared in the same pond, suggesting that the parasite has a relatively strict host specificity. Plasmodia grew gradually as the parasite developed, and reached up to a maximum 5.6 mm in diameter. Plasmodia ruptured naturally to release the mature spores and host fish completely recovered with no mortality. Release of spores and regeneration of lesions were not correlated with water temperature. Histology showed that plasmodia developed sub-epidermally, and that the wall of the plasmodia was composed of a multiple complex structure, including layers of fibroblasts, a collagenous membrane, melanophores and a layer of cup-like cells of unknown derivation and function. The cup-like cells are in direct contact with pre-sporogonic stages located in the peripheral parts of the large plasmodia. No severe host inflammatory response was seen. [ABSTRACT FROM AUTHOR]

The frequent disease outbreaks caused by avian influenza virus (AIV) not only affect the poultry industry but also pose a threat to human safety. To address the problem, RNA interference (RNAi) has recently been widely used as a potential antiviral approach. Transgenesis, in combination with RNAi to specifically inhibit AIV gene expression, has been proposed to make chickens resistant to avian influenza. For the transgenic breeding, screening the efficient siRNAs in vitro as the candidate genes is one of the most important tasks. Here, we combined an online search tool and a series of bioinformatics programs with a set of rules for designing the siRNAs targeting different mRNA regions of AIV H5N1 subtype. By this method we chose five rational siRNAs, constructed five U6 promoter-driven shRNA expression plasmids contained the siRNA genes, and used these to produce stably transfected Madin-Darby canine kidney (MDCK) cells. Data from virus titration, IFA, PUI-stained flow cytometry, real-time quantitative RT-PCR and DAS-ELISA analyses showed that all five stably transfected cell lines were effectively resistant to viral replication when exposed to 100 CCID50 of AIV, and we finally chose the most effective plasmids (pSi-604i and pSi-1597i) as the candidates for making the transgenic chickens. These findings provide baseline information for breeding transgenic chickens resistant to AIV in combination with RNAi. [ABSTRACT FROM AUTHOR]

Abstract: The transition of BaOD has been rotationally analyzed using laser excitation spectroscopy. BaOD molecules were synthesized through the reaction of Ba atoms with D2O in a Broida-type oven. Rotational and fine structure parameters determined for the state of BaOD yielded a spin-orbit coupling constant A significantly different from the corresponding value for BaOH (∼605.8cm−1 versus 560.1cm−1). Λ-doubling constants for the state were observed to be in poor agreement with the predictions of the pure precession model for the interaction between the and the states in BaOD. Explanations for the unusual spin-orbit splitting and apparent failure of the pure precession and unique perturber models in BaOH and BaOD are discussed, with particular reference to possible global and local perturbations arising from vibrationally excited bands of the state. [Copyright &y& Elsevier]

The tests were performed on low carbon steel plate. In the tension fatigue tests, two angle values (φ = 0° and φ = 45°) have been chosen, which were the angles between the loading and the rolling direction. The influence of strain path change on the subsequent initial work softening rate and the saturation stress has been investigated. Dislocation microstructure was observed by transmission electron microscopy. It was found that the strain amount of preloading in tension has obviously affected the cyclic softening phenomenon and the initial cyclic softening rate. It was observed that the reloading axial stress for φ = 45° case increased more than that of φ = 0°? case, due to the anisotropism of Q235. In the fatigue crack propagation tests, the experimental results show that with increasing the pretension deformation degree, the fatigue crack growth rate increases, especially at the near threshold section. [ABSTRACT FROM AUTHOR]

A wrap method adaptation combined with AutoCAD2005 and Scion Image for Windows were used to determine the surface area of a fish. Compared with the corresponding r2 and F of many models, the most accurate formula: S = 752.15W0.675 (r2 = 0.999, F = 18362.94, P < 0.0001) for estimating the surface area of common carp was obtained. Similarly, the fin formula: S = 1834.12W0.708 (r2 = 0.992, F = 2690.47, P < 0.0001) was also obtained for the same purpose. It was proven that these two formulae gave good estimates of surface and fin areas of four strains of common carp: Yellow-river carp, fancy carp, mirror carp and Xingguo red carp. [ABSTRACT FROM AUTHOR]

Abstract: The high-resolution spectrum of the transition of BaOH has been recorded using laser excitation spectroscopy. The BaOH molecules were synthesized through the reaction of Ba atoms with H2O2 in a Broida-type oven. Rotational and fine structure parameters have been determined for the state through a combined least-squares fit with the millimeter-wave pure rotational data of the state. The Λ-doubling constants observed for the state are in poor agreement with the predictions of the pure precession model of the interactions between the and the states of BaOH. In addition to the bands of the transition, three bands located at ∼11443cm−1, ∼12013cm−1 and ∼12505cm−1, respectively, were also observed and analyzed but their vibrational and electronic assignments are not clear. Possible assignments of the three unidentified bands are discussed based on the derived spectroscopic constants and the vibrational assignments of previous low-resolution work. [Copyright &y& Elsevier]

Abstract: The and states of SrOH were investigated using optical–optical double-resonance (OODR) spectroscopy. Rotational and fine structure parameters have been determined for these two states through a combined least-squares fit of the current OODR data along with the OODR data of the transition, the optical data of the transition and the millimeter-wave pure rotational measurements of the state. The spin–rotation constant, γ, of the state was found to be 0.002653cm−1, which is two orders of magnitude smaller than that of the state (−0.1447cm−1). This small γ value suggests that this state arises from a Sr+ atomic orbital of mainly 6sσ character. This atomic orbital assignment is also supported by the large rotational constant observed in the state and the similarity of the molecular constants to those of the state of CaOH. The rotational energy levels of the state of SrOH were found to be largely perturbed, which prohibited the accurate determination of the spin–rotation constant in this state. This perturbation is most likely due to an interaction with a 2Σ vibronic component of the nearby state. [Copyright &y& Elsevier]

We address the structure gap between surface science and catalysis studies of the activity of oxide supported Au clusters. Reviewing the recent literature we find that surface science investigations often deal with highly reduced systems that have anionic Au clusters and oxygen vacancies in the support. The catalysis studies on the other hand consistently report on oxidized samples with traces of cationic Au. Performing density functional theory calculations we show that the effect of oxidation of oxide supported Au clusters, Au8/MgO, Au7/TiO2 and Au10/TiO2, is a strong increase in the Au/support adhesion energy and a great structural transformation of the clusters. Some of the Au atoms become positively charged (cationic) in the oxidation process as evidenced indirectly by calculated vibrational stretch frequency shifts of adsorbed CO. [ABSTRACT FROM AUTHOR]

The processes of charge exchange and ionization in collisions of ground state hydrogen atom with fully stripped ions in a weakly coupled plasma are studied by the classical trajectory Monte Carlo method in the collision energy range 10–900 keV/amu. The interparticle interactions are described by the Debye-Hückel model with inclusion of dynamical effects associated with the projectile velocity. The microcanonical distribution of initial state electronic coordinates and momenta has been determined by inclusion of plasma screening effects. The cross section dependencies on plasma parameters and ion charge and velocity are investigated. It is shown that plasma effects on charge exchange and ionization cross sections are significant and particularly pronounced at low collision velocities. The results of systematic cross section calculations for different values of Debye screening length (in the range 1–50a0) and ion charges (in the range 1–14) are presented. [ABSTRACT FROM AUTHOR]

We studied the nucleation of gold clusters on TiO2(110) surfaces in three different oxidation states by high-resolution scanning tunneling microscopy. The three TiO2(110) supports chosen were (i) reduced (having bridging oxygen vacancies), (ii) hydrated (having bridging hydroxyl groups), and (iii) oxidized (having oxygen adatoms). At room temperature, gold nanoclusters nucleate homogeneously on the terraces of the reduced and oxidized supports, whereas on the hydrated TiO2(110) surface, clusters form preferentially at the step edges. From interplay with density functional theory calculations, we identified two different gold-TiO2(110) adhesion mechanisms for the reduced and oxidized supports. The adhesion of gold clusters is strongest on the oxidized support, and the implications of this finding for catalytic applications are discussed. [ABSTRACT FROM AUTHOR]

Family investigation is a reliable model to study the effects of both genetic and environmental factors on human health. This article studies kidney-yang deficiency syndrome and cold syndrome through family investigation and cDNA microarray technology, exploring the effects of both genetic and environmental factors on the health of family members. Particularly, these two syndromes were first assessed by the accumulated clinical scores measured by 40-item scoring tables among 15 family members. The family patterns were obtained and the correlation of these two syndromes was determined. Then the gene differential expression profiles among 12 family members were obtained using an 18,816 clones cDNA microarray. The profiles of the patients with typical kidney-yang deficiency syndrome and cold syndrome were compared to those of normal members and 89 differential expression genes were found. Further, only 22 genes were identified as known functions, and most (16 genes) were associated with the regulation of metabolism, temperature feeling, and growth. Therefore, the formation and development of these two syndromes have not only genetic but also environmental factors, including living conditions and lifestyle. [ABSTRACT FROM AUTHOR]

Abstract: Optical–optical double-resonance spectroscopy has been used to record a high-resolution spectrum of the transition of SrOH. Rotational and fine structure parameters have been determined for the state through a combined least-squares fit with the optical transition data and the millimeter-wave pure rotational data of the state. The spin-orbit constant of the state was found to be 24.6607cm−1, which is significantly smaller than in the à 2Π state. This change can be rationalized by the different atomic orbital character of the à 2Π and states. The values of the Λ-doubling constants in the state have been examined in terms of the pure procession model. The agreement between the calculated and observed Λ-doubling constants suggests that the state may form a unique perturber pair with the nearby state. [Copyright &y& Elsevier]

Immunological methods have been developed for the diagnosis of Myxobolus rotundus but their use has been limited for the prevention and therapy of this serious parasitic pathogen. Phage display antibody libraries are a powerful technique for the development of antibodies to molecules of interest and have advantages over traditional hybridroma approaches. In the present study, four antigen fractions related to M. rotundus were prepared and a combined phage display single-chain antibody fragments (ScFv) library was constructed against this parasite. Preliminary analysis indicated that a combined antibody library of about 2.08 x 105 individual clones and high diversity was generated. After four rounds of screening (bio-panning) against soluble spore protein prepared from lysed, intact, mature M. rotundus spores, a strain monoclonal phage display ScFv, termed pCAN-6H9, with better affinity, was isolated. The pCAN-6H9 gene fragment was sequenced and analysed. The specificity of pCAN-6H9 was further demonstrated by dot-blot. In competition enzyme-linked immunosorbent assay, both the original and enriched phage-displayed ScFv repertoire showed significant inhibition of mouse anti-M. rotundus serum binding to coated antigen, while the inhibition rate of monoclonal pCAN-6H9 phage particles was only 11.83%. [ABSTRACT FROM AUTHOR]

The effect of La2O3 addition on the microstructure of partially remelted Mg-9Al-1Zn (AZ91D) alloy was studied. The results indicate that small amounts of La2O3 additions to AZ91D alloy refined the partially remelted microstructure and caused the formation of new phase- LaAl4 in the microstructure. Moreover, the grain size of the partially remelted alloys is decreased with the increasing of La2O3 addition. In as-cast microstructure the LaAl4 phases have two morphologies: needle-like and particle-shape. The presence of more LaAl4 phases, especially, the particle-shape LaAl4 which dispersedly distributed within the grains can induce more dislocations, which can result in the occurring of a large amount of recrystallizations. Moreover, these LaAl4 phases can also restrain the growth and combination of the recrystallizations and partially remelted initial grains during the subsequent heat-treatment. [ABSTRACT FROM AUTHOR]

Isolated systolic hypertension affects over 15% of all individuals aged >60 years. In the elderly, systolic hypertension is a major modifiable cardiovascular risk factor. Systolic blood pressure (SBP) is associated with higher risk of an adverse outcome, whereas diastolic blood pressure (DBP) is inversely correlated with total mortality, independent of SBP, highlighting the role of pulse pressure as a risk factor. Three placebo-controlled outcome trials on antihypertensive drug treatment in older patients with isolated systolic hypertension have been published: the Systolic Hypertension in the Elderly Program (SHEP), the Systolic Hypertension in Europe (Syst-Eur) Trial and the Systolic Hypertension in China (Syst-China) Trial. These 3 trials demonstrated the benefit of antihypertensive drug treatment. A meta-analysis was performed by pooling the patients from these 3 trials with a subset of patients with isolated systolic hypertension from 5 other trials in the elderly. The pooled results of 15 693 older patients with isolated systolic hypertension prove that antihypertensive drug treatment is justified if on repeated clinic measurements SBP is 160mm Hg or higher. [ABSTRACT FROM AUTHOR]

Three intersection mechanisms with the gliding planes (111)[sub TB], (001)[sub TB] and (115)[sub TB] respectively have been observed by high-resolution electron microscopy in the type-I twin intersection of gamma-TiAl. It was found that the intersection mechanism that occurred was related to the thickness of the incident twin. The accommodation mechanism on the (111)[sub TB] atomic plane is preferred when the incident twin becomes very thin. The dislocation dissociations of the (111)[sub TB] plane accommodation are the most energetically unfavourable of the dissociations of the three intersection mechanisms; however, the resultant dislocations on the (111)[sub TB] planes are the easiest to propagate away from the intersection area. Accordingly, (111)[sub TB] atomic plane accommodation is considered to be the only mechanism allowing shear transmission under the small local stress of the pile-up of the incident twinning partials. [ABSTRACT FROM AUTHOR]