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A novel self-oscillating microgels were prepared by copolymerization N-isopropylacrylamide (NIPAAm), organic acid and iron(II) 5-acrylamide-1,10-phenanthroline-bi (1,10-phenanthroline) (Fe(phen)), the catalyst for the Belousov-Zhabotinsky (BZ) reaction. The microgels were characterized by FTIR spectroscopy and scanning electron microscope (SEM). In order to illustrate the self-oscillating mechanism, the static water contact angles of the oxidized and reduced states of self-oscillating microgels were measured. In addition, the self-oscillating behaviors of the microgels were investigated in BZ system under acid-free conditions. Both the redox potential and transmittance self-oscillating were observed at room temperature. [ABSTRACT FROM AUTHOR]

This study was carried out to investigate the exact mechanisms behind the neuroprotective effects of oleoylethanolamide (OEA) after acute cerebral ischemic injury. Transient focal cerebral ischemia was induced by middle cerebral artery occlusion (MCAO) for 90 min followed by reperfusion. OEA (40 mg/kg, ip) was administered with a single injection upon reperfusion. The number of apoptotic cells was detected by TUNEL staining. The expression of Bax, Bcl-2, and TLR4, as well as the activities of NF-κB, Akt, and ERK1/2 were analyzed by western blot. Our data showed that OEA treatment alleviated cell apoptosis in a mouse model of ischemic stroke, accompanied by suppression of Bax, as well as upregulation of antiapoptotic protein Bcl-2 level. The changes of Bax and Bcl-2 could not be observed in PPARα knockout mice models with OEA administration. Importantly, OEA inhibited MCAO-induced TLR4 expression, NF-κB activation, IκBα degradation, and ERK1/2 phosphorylation. Our findings demonstrated that the neuroprotective effects of OEA on cerebral ischemia may be attributed to its antiapoptotic property achieved, at least in part, through the PPARα signaling and inhibition of both TLR4/NF-κB and ERK1/2 signaling pathways. These results provide new evidence indicating the neuroprotective effect of OEA on ischemic stroke. [ABSTRACT FROM AUTHOR]

Robot manipulators enable large-scale factory automation of simple and repeated tasks. Each manipulation is the result of the robot design and the command inputs provided by the operator. In this study, we focus on the accuracy improvement of practical robot manipulation under uncertainty, resulting in path-specific error values. Existing techniques for reducing the errors use high-precision sensors and measurements to obtain the values of a manipulator to provide feedback control. Instead of compensating errors in operation, this study designs a calibration table to obtain the error value for a designated path. This error is then used to adjust important parameters in the kinematic closed chain models of a manipulators via optimization. The proposed method reduces the cost and the dependence on the calibration process. Experimental results show that the overall accuracy of the manipulator is improved. The proposed method can also be extended to develop the optimal robotic manipulation planning and reliability assessment in the future. [ABSTRACT FROM AUTHOR]

Using Pearson's hard and soft acids and bases (HSAB) principle as the design guideline, a novel chitosan/poly(ethylene glycol)/poly(acrylic acid) (CS/PEG/PAA) hydrogel adsorbent containing hard Lewis base adsorption site (i.e., amino group, hydroxyl group, ether linkage, carboxylate ions) was prepared by glow-discharge electrolysis plasma (GDEP) technique and then applied for the selective adsorption of Pb. A copolymerization mechanism initiated by GDEP was proposed. The structure, thermal stability, and morphology of CS/PEG/PAA adsorbent were characterized by FT-IR, thermogravimetry/differential thermogravimetry (TG/DTG), and SEM. The effects of the solution pH and contact time on the single-component adsorption were examined by batch experiments. Competitive adsorptions of Pb and Cd were carried out under equal mass concentration and equal molar concentration. In addition, regeneration and reusability of adsorbent were also investigated in detail. The results showed that the maximum adsorption capacities for Pb and Cd are 431.7 and 265.0 mg g, respectively. The kinetic behaviors of the adsorption and the fourth desorption for single component and the competitive adsorption for Pb follow the pseudo-second-order model with pH = 4.8. The CS/PEG/PAA adsorbent has good adsorption selectivity for Pb with the coexistence of Cd. The adsorbent displays excellent regeneration and reusability in the EDTA-4Na solution. [ABSTRACT FROM AUTHOR]

Linguistic pairwise comparison matrices for decision-making need to be (strongly) order-consistent, which means the judgments should be (strongly) transitive. We introduce the equivalent conditions of (strong) transitivity by using route matrices and digraphs and develop an adjustment procedure to help decision makers correcting the inconsistency. The conclusion can extend to other ordinal-scaled or numerical comparison matrices as well. [ABSTRACT FROM AUTHOR]

A novel self-oscillating copolymer was prepared by utilizing Fe(phen) as the catalyst of the Belousov -Zhabotinsky (BZ) reaction. In this study, 2-acrylamido-2-methylpropane sulfonic acid (AMPS) was newly introduced into the copolymer of N-isopropylacrylamide (NIPAAm) and Fe(phen) as the Hproviding agent for the BZ reaction. The results indicated that the copolymer solution underwent soluble-insoluble self-oscillation only in malonic acid (MA) and potassium bromate(KBrO) mixture solution, and the amplitudes were much bigger than those of poly(NIPAAm- co-Fe(phen)). That is to say, the novel copolymer succeeds in self-oscillating under acid-free conditions. Moreover, the oscillating characteristics were closely related to the content of AMPS in the copolymer. [ABSTRACT FROM AUTHOR]

A novel kind of microgels, poly(NIPAAm- co-Fe(phen)- co-AAc), were prepared by copolymerization N-isopropylacrylamide (NIPAAm), acrylic acid (AAc) and iron(II) 5-acrylamide-1,10-phenanthroline-bi(1,10-phenanthroline) (Fe(phen)), the catalyst for the Belousov-Zhabotinsky (BZ) reaction. The microgels were characterized by FT-IR spectroscopy, X-ray photoelectron spectroscopy (XPS), dynamic light scattering (DLS) and scanning electron microscope (SEM). In addition, the self-oscillating behaviors of the microgels were investigated in BZ system free of catalyst. Both the redox potential and transmittance self-oscillation were observed. Moreover, the amplitudes of poly(NIPAAm- co-Fe(phen)- co-AAc) microgels are much larger than those of linear polymer and gel. This advantage originated from the special structure, size and composition of the microgels. [ABSTRACT FROM AUTHOR]

Natural landscapes consist of the natural substances, environment, and phenomena, all of which provide many benefits to people, including a sense of place, sightseeing, relaxing, and recuperating. However, the economic value of natural landscapes has only been recognized in recent decades, and the resulting large-scale decline and degradation of ecosystems now severely threatens the sustainable provision of their services to society. There is an emerging consensus that natural capital should be incorporated into the current socioeconomic accounting system. Many studies valuated natural resources at local and regional scales, but there are very few empirical studies at a national level. To provide a benchmark for natural landscape management on a national scale, we use the travel cost method (TCM) and the contingent valuation method (CVM) to determine the economic value and the spatial distribution of natural landscapes across China. Our results show that the total economic value of China′s natural landscape was 9.75 × 10 U.S. dollars (USD) in 2012. Of this value, the highest proportion was in the eastern and southwestern regions of China, which accounts for 23.7% and 18.3%, respectively. The provinces of Guangdong, Sichuan, Yunnan, Inner Mongolia, and Heilongjiang were the top five in terms of the largest number of natural landscapes and largest economic values. Together, these five provinces accounted for 32.9% of the total number of natural landscapes and 29.4% of the total economic value in 2012. We believe this study will increase awareness of the value of natural landscapes, and more importantly provide a scientific basis for resolving conflicts between development and resource conservation. [ABSTRACT FROM AUTHOR]

Devastating tsunami waves can mobilize substantial amount of coastal sediment. Scouring is the primary damage caused by tsunamis. Offshore submerged or emerged breakwaters are coastal structures that are commonly employed to provide protection to valuable coastal beaches from energetic ocean waves. However, the protection capabilities of tsunami scour by submerged or emerged breakwater are less understood compared to tsunami runup and tsunami inundation. A set of laboratory experiments are reported in this study on protection of tsunami-induced scour by submerged or emerged breakwaters on a sandy beach. FLOW-3D is used in this paper to calculate flow field of tsunami wave propagation over the breakwater in order to help us to understand the sediment transport and tsunami scour process. Our experiments show that the submerged breakwater could not effectively reduce the tsunami scouring and only could affect the height and position of deposition sand bar. The emerged breakwater could significantly effectively reduce the tsunami scouring on the sandy beach; meanwhile, local scouring caused by plunging jet occurs mainly on the both sides of the structure. It is also found that for typical tsunamis, the scour depth at shoreward is unlikely to reach its equilibrium stage. Local scouring damage is one of the main factors leading to the destruction of coastal structures during a tsunami event. The most important governing parameters on local scouring around breakwater were defined. The final empirical relations that define the magnitude and position of local scouring around the breakwater were presented. The information reported in this study is useful for local authorities to assess potential tsunami damage of structure and to have a better plan for tsunami preventing and reducing. [ABSTRACT FROM AUTHOR]

A palygorskite/poly(2-acrylamido-2-methyl-1-propanesulfonic acid-co-acrylamide) (PGS/P(AMPS-co-AM)) superabsorbent hydrogel was prepared in aqueous solution using glow-discharge electrolysis plasma (GDEP) as an initiator and N, N′-methylene-bis-acrylamide as a cross-linker. A possible copolymerization mechanism initiated by GDEP was proposed. The structure, thermal stability, and morphology of PGS/P(AMPS-co-AM) were characterized by FT-IR, XRD, TG-DTG, and SEM. The swelling kinetics, pH-reversibility, and influence of various pH and salt solutions on the swelling were investigated. Adsorption kinetics and adsorption mechanism of hydrogel for dyes were studied in detail. The results indicated that the equilibrium swelling of hydrogel is 652.6 g g in distilled water. The swelling of the hydrogel in salt solutions from highest to lowest is Na > Mg > Fe. The hydrogel has pH-reversibility responsive to the pH and salts solutions. The adsorption process of dyes follows the pseudo-second-order kinetic model with multi-step diffusion process. In addition, PGS/P(AMPS-co-AM) hydrogel can be regenerated and reused. [ABSTRACT FROM AUTHOR]

Artificial materials with controllable wettability are of global interests in oil-water related applications. In the present report, a surface with superhydrophilicity/superoleophilicity and underwater superoleophobicity was constructed on filter paper via dip-coating ZnO colloids. However, the wettability of the filter paper was converted to be superhydrophobic and superoleophilic after being modified by octyltrimethoxysilane, and water contact angle on the surface is larger than 150° while oil contact angle is smaller than 5°. The filter paper can be employed to selectively adsorb oil floating on water or separate water-oil mixtures via filtration process because of its superhydrophobicity and superoleophilicity. Additionally, the filter paper has also the capacity to hold water, which is expected to be used as a material for manufacturing labwares. Graphical Abstract: A filter paper with superhydrophobicity and superoleophilicity was fabricated by dip-coating and subsequent modification. Water contact angle and sliding angle on the filter paper are 157°and 6°, respectively. The filter paper with superhydrophobicity and superoleophilicity could be employed to separate oil-water mixture with high efficiency.[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Traditional anomaly detection on microblogging mostly focuses on individual anomalous users or messages. Since anomalous users employ advanced intelligent means, the anomaly detection is greatly poor in performance. In this paper, we propose an innovative framework of anomaly detection based on bipartite graph and co-clustering. A bipartite graph between users and messages is built to model the homogeneous and heterogeneous interactions. The proposed co-clustering algorithm based on nonnegative matrix tri-factorization can detect anomalous users and messages simultaneously. The homogeneous relations modeled by the bipartite graph are used as constraints to improve the accuracy of the co-clustering algorithm. Experimental results show that the proposed scheme can detect individual and group anomalies with high accuracy on a Sina Weibo dataset. [ABSTRACT FROM AUTHOR]

We investigative the field distribution in a limited number of nanostructured metal waveguide arrays. The precise positions of self-imaging are obtained. We derive the perturbation constant and the coupling constant by perturbation approach and supermode theory in a system that contains two adjacent waveguides. The perturbation constant and the coupling constant can also be applied to the systems that contain more than two adjacent waveguides. The cases of N $$=$$ 3 and N $$=$$ 4 are analyzed. Our theories are verified by the finite-difference time-domain method. Numerical simulation results show a good agreement with the theoretical predictions. [ABSTRACT FROM AUTHOR]

A novel self-oscillation polymer was successfully synthesized by covalently bonding the Fe(phen) catalyst for the BZ reaction onto the poly(N-isopropylacrylamide) polymer chain. The lower critical solution temperatures (LCST) of the polymer chain in the reduced and oxidized states were 37 and 32 °C, respectively. The prepared polymer solution can undergo soluble-insoluble self-oscillation induced by the BZ reaction at constant temperature. [ABSTRACT FROM AUTHOR]

Various semi-interpenetrating polymer network (semi-IPN) hydrogels composed of pore-forming agent polyethylene glycol (PEG), acrylic acid (AA) and acrylamide (AM) were prepared by using free radical polymerization with a two-step method. The chemical structures of the synthesized hydrogels were characterized by FTIR spectroscopy and the morphologies were studied by scanning electron microscopy (SEM) method. The swelling properties, such as the pH-responsive behavior, salt sensitivity, oscillatory swelling/de-swelling behaviors in different solutions with various pH values and self-oscillating behaviors in bath pH oscillator were investigated in detail. The results revealed that the prepared hydrogels exhibited high pH sensitivity and excellent salt sensitivity when the pH values of the medium changes from 3.0 and 7.0 and well reversible properties by undergoing a number of swelling/de-swelling recycles. In particular, the hydrogels exhibited self-oscillation behavior in a closed system containing BrOSOFe(CN)H. This study may create a new possibility as biomaterial for new self-walking actuators and other devices. [ABSTRACT FROM AUTHOR]

While the effects of lattice mismatch-induced strain, mechanical strain, as well as the intrinsic strain of thin films are sometimes detrimental, resulting in mechanical deformation and failure, strain can also be usefully harnessed for applications such as data storage, transistors, solar cells, and strain gauges, among other things. Here, we demonstrate that quantum transport across magnetic tunnel junctions (MTJs) can be significantly affected by the introduction of controllable mechanical strain, achieving an enhancement factor of ~2 in the experimental tunneling magnetoresistance (TMR) ratio. We further correlate this strain-enhanced TMR with coherent spin tunneling through the MgO barrier. Moreover, the strain-enhanced TMR is analyzed using non-equilibrium Green's function (NEGF) quantum transport calculations. Our results help elucidate theTMRmechanism at the atomic level and can provide a new way to enhance, as well as tune, the quantum properties in nanoscale materials and devices. [ABSTRACT FROM AUTHOR]

In order to improve the performance and efficiency of truss structure optimization, this paper presents a general framework that embeds and seamlessly integrates commercial CAD and CAE software through common programming languages and application programming interface (API). Along with the automatic CAD/CAE integration, an adaptive metamodel-based optimization called sequential radial basis function (SRBF) is applied to truss structure optimization involving sizing, geometry and topology variables. SRBF distinguishingly features two-loops searching strategy, the 'inner loop' and the 'outer loop'. The 'inner loop' aims to search a feasible point through updating the factors of the augmented Lagrangian function. With the improved significant sampling space (ISSS) method, the 'outer loop' sequentially generates new additional samples to update the RBF model. The continuous relaxation method is developed to deal with the mixed-discrete variables during the truss structure optimization. Applied to practical truss structure optimization problems from small scale to large scale, the proposed framework demonstrates feasibility of the CAD/CAE integration system during the structure modeling and analysis, and facilitates the truss structure optimization process. The comparison results between the SRBF and other approaches show that SRBF improves merit of searching global optimum and reduces the computation cost. [ABSTRACT FROM AUTHOR]

The Baerzhe alkaline granite pluton hosts one of the largest rare metal (Zr, rare earth elements, and Nb) deposits in Asia. It contains a geological resource of about 100 Mt at 1.84 % ZrO, 0.30 % CeO, and 0.26 % NbO. Zirconium, rare earth elements (REE), and Nb are primarily hosted by zircon, yttroceberysite, fergusonite, ferrocolumbite, and pyrochlore. Three types of zircon can be identified in the deposit: magmatic, metamict, and hydrothermal. Primary magmatic zircon grains occur in the barren hypersolvus granite and are commonly prismatic, with oscillatory zones and abundant melt and mineral inclusions. The occurrence of aegirine and fluorite in the recrystallized melt inclusions hosted in the magmatic zircon indicates that the parental magma of the Baerzhe pluton is alkali- and F-rich. Metamict zircon grains occur in the mineralized subsolvus granite and are commonly prismatic and murky with cracks, pores, and mineral inclusions. They commonly show dissolution textures, indicating a magmatic origin with later metamictization due to deuteric hydrothermal alteration. Hydrothermal zircon grains occur in mineralized subsolvus granite and are dipyramidal with quartz inclusions, with murky CL images. They have 608 to 2,502 ppm light REE and 787 to 2,521 ppm Nb, much higher than magmatic zircon. The texture and composition of the three types of zircon indicate that they experienced remobilization and recrystallization during the transition from a magmatic to a hydrothermal system. Large amounts of Zr, REE, and Nb were enriched and precipitated during the transitional period to form the giant low-grade Baerzhe Zr-REE-Nb deposit. [ABSTRACT FROM AUTHOR]

The aggravating effects of zero-dimensional, particle-shaped nanomaterials on allergic asthma have been previously investigated, but similar possible effects of one-dimensional shaped nanomaterials have not been reported. More importantly, there are no available means to counteract the adverse nanomaterial effects to allow for their safe use. In this study, an ovalbumin (OVA)-sensitized rat asthma model was established to investigate whether single walled carbon nanotubes (SWCNTs) aggravate allergic asthma. The results showed that SWCNTs in rats exacerbated OVA-induced allergic asthma and that this exacerbation was counteracted by concurrent administration vitamin E. A mechanism involving the elimination of reactive oxygen species, downregulation of Th2 responses, reduced Ig production, and the relief of allergic asthma symptoms was proposed to explain the antagonistic effects of vitamin E. This work could provide a universal strategy to effectively protect people with allergic asthma from SWCNTs or similar nanomaterial-induced aggravating effects. [ABSTRACT FROM AUTHOR]

Purpose: Analyze protein and gene expression of mGluRs (mGluR1, mGluR5, mGluR4) in osteosarcoma tissues and discuss the relation between expression level and clinical characteristics of osteosarcoma, and study the clinical significance. Methods: Detect protein and mRNA expression level of mGluRs (mGluR1, mGluR5, mGluR4) in 40 osteosarcoma tissues and the corresponding adjacent normal tissues by Western blot and RT-PCR accordingly. Immunohistochemistry was adopted to detect the expression of mGluRs (mGluR1, mGluR5, mGluR4) in 118 paraffin embedded osteosarcoma tissues and eight normal bone tissues. Then, the correlation between the expression and clinical characteristics of patients was analyzed. Furthermore, survival analysis of osteosarcoma was performed to study the relation between expression level of mGluRs and patient prognosis. Results: No correlation of mGluR1 and mGluR5 with clinicopathologic characteristics of osteosarcoma was found. Statistical analysis demonstrated that the expression level of mGluR4 shared no significant correlation with gender, age, histologic type and tumor location of patient, but was related to Enneking stage and tumor metastasis ( P < 0.05). High mGluR4 expression is more frequently noted in the osteosarcoma tissues with higher Enneking stage and metastasis. The results of Western blot and RT-PCR indicated a significantly increased expression level of mGluR4 gene and protein in osteosarcoma tissues compared with normal tissues. Though higher gene and protein expression of mGluR5 and mGluR1 were also indicated in osteosarcoma tissues compared with normal tissues, no statistical significance was noted for the difference ( P > 0.05). According to the survival analysis of 118 osteosarcoma patients, cases in the mGluR4 high-expression group showed inferior disease-free survival rate and poorer overall survival rate. Conclusion: High expression of mGluR4 in osteosarcoma tissues is related to poor prognosis, thus holding certain reference value for estimating prognosis of osteosarcoma patients. [ABSTRACT FROM AUTHOR]

Integrin controls cell adhesion to extracellular matrix and plays an important role in regulating the proliferation and apoptosis of cells. In order to explore the role of ITGA3 gene polymorphisms in the pathogenesis and clinicopathological characteristics of osteosarcoma, we embarked on a study including a group of 118 patients and a group of 126 healthy controls. TaqMan PCR genotyping technology was used to detect the genotypes of ITGA3 gene SNPs (rs2230392, rs2285524 and rs16948627) in the peripheral blood. Then, associations of the SNP (rs2230392, rs2285524 and rs16948627) genotypes with the incidence risk and tumor characteristics of osteosarcoma were evaluated. A significant difference ( P = 0.02) in the genotype frequency distribution of rs2230392 was observed between case and control groups. The analysis showed that patients carrying AA genotype had a higher risk of osteosarcoma (OR 2.34, 95 % CI 1.18-4.64) than those with GG genotype. Regarding rs2230392, men carrying AA genotype had a higher risk of osteosarcoma (OR 3.37, 95 % CI 1.25-9.11). Compared with those with GG genotype, patients carrying AA genotype had a twofold increased risk of osteosarcoma metastasis (OR 2.46, 95 % CI 1.09-5.57). Survival analysis showed that for rs2230392, survival time of osteosarcoma patients with three different genotypes was significantly different. Polymorphisms of ITGA3 gene rs2230392 may affect the incidence, metastasis and survival of osteosarcoma, which may clinically become a new target for predicting the risk of osteosarcoma, and have prognostic value. [ABSTRACT FROM AUTHOR]

Our previous studies indicated that a purified rabbit antiserum against X-sperm contained sex-specific antibodies (SSAbs) which preferentially bound to sex-sorted X-sperm. The specificity of sex-specific antiserum was initially demonstrated using flow cytometry only, which resulted in uncertainty. In this study, the putative SSAbs against bovine X-sperm (XSSAb) were produced by a series of immunological approaches, and the effectiveness of separation of sperm using putative XSSAb was validated. Subsequently, the XSSAb was used to immunoprecipitate sex-specific proteins (SSPs) in bovine sperm, followed by two-dimensional gel electrophoresis. The results showed 7.6, 15.2 and 52.1 % of sex-sorted Y-sperm, sex-sorted X-sperm and unsorted sperm were recognized by the neutralized rabbit antisera against X-sperm, respectively. Also the purity of separation of sperm using putative XSSAb reached 74.3 % when the immunologically separated sperm were injected into oocytes. In addition, three candidate SSP sports about 30 kDa were captured by the XSSAb. Our results confirmed that the putative XSSAb contained SSAbs, and implied that these three protein sports might be SSPs in bovine X-sperm. This provides a potentially more efficient method for sorting sperm and lays a foundation for future search for SSPs. [ABSTRACT FROM AUTHOR]

A highly oriented ZnO nanorod array film was fabricated on glass substrate by combinations of Sol-Gel and hydrothermal. The film exhibits perfect superhydrophobicity with a contact angle of 155° and a glide angle of 4° after being surface modified by fluoroalkylsilane, which is similar with wings' property and structures of large yellow spots mosquitoes. Interestingly, the ZnO nanorods film were converted from superhydrophobicity into superhydrophilicity under ultraviolet light for 2 h due to the decomposition of fluoroalkyl chain of fluoroalkylsilane and the photosensitivity of ZnO surface. The transition mechanisms of wettability are discussed on the basis of correlated theories. [ABSTRACT FROM AUTHOR]

Superhydrophobic silver nanocoatings with feather-like morphology are fabricated on copper substrates by electroless galvanic deposition. The coating exhibit superhydrophobicity with a contact angle of 156.4° and glide angle of 4° without any further surface modification. Scanning electron microscope (SEM), X-ray diffraction (XRD) and contact angle measurements are used to investigate the morphology, crystal structure and superhydrophobicity, respectively, of the coatings. The coatings exhibit high thermal stability; their water contact angle did not change when the coatings were heated to 200°C for 2 h. The mechanism of superhydrophobicity of the silver coating is discussed based on the work of Amirfazli, Wenzel and Cassie. [ABSTRACT FROM AUTHOR]

The closed form solutions of the stress and displacement in strain softening rock mass around a newly formed cavity are derived with a three step-wise elasto-plastic model. Hoek-Brown criterion is adopted as the yielding criterion of rock mass. Damage factors are proposed to account for degradation of the material parameters to reflect the degree of strain softening. The surrounding rock mass around the cavity is divided into three regions: elastic region, strain softening region and residual state region. The analytical solutions of stress, strain, displacement and radius of each region are obtained. The effects of the strain softening and shear dilatancy behavior on the results are investigated with parametric studies. The results show that the radii of the residual state region and strain softening region in the surrounding rock mass with higher damage degree are larger. The radii of the residual state region and strain softening region are 1-2 times and 1.5-3 times of the cavity radius, respectively. The radial and tangential stresses decrease with the increase of the damage factor. The displacement of the cavity wall for the case with maximum plastic bulk strain is nearly twice than that with no dilation. Rock mass moves more toward the center for the case with larger damage factor and shear dilation. The area of the plastic region is larger when the damage factors are considered. The displacements in the surrounding rock mass increase with the increase of the damage factors and shear dilation factors. The solutions can be applied to the stability analysis and support design of the underground excavation. [ABSTRACT FROM AUTHOR]

Highly swelling P(2-acrylamido-2-methyl-1-propanesulfonic acid- co-acrylic acid) (P(AMPS- co-AAc)) superabsorbent hydrogel was synthesized in aqueous solution by a simple one-step using glow-discharge electrolysis plasma technique, in which N,N'-methylenebisacrylamide was used as a crosslinking agent. The structure, thermal stability and morphology of P(AMPS- co-AAc) superabsorbent hydrogel were characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis, and scanning electron microscopy. A mechanism for synthesis of P(AMPS- co-AAc) superabsorbent hydrogel was proposed. The reaction parameters affecting the equilibrium swelling (i.e., discharge voltage, discharge time, macroscopic temperature of the liquid phase, mass ratio of AMPS to AAc, and content of crosslinker) were systematically optimized to achieve a superabsorbent hydrogel with a maximum swelling capacity. The hydrogel formed which absorbed about 1,685 g HO/g dry hydrogel of the optimized product was used to study the influence of various pH values and salts solutions (NaCl, KCl, MgCl, and CaCl) on the equilibrium swelling. In addition, swelling kinetics in distilled water and on-off switching behavior were preliminarily investigated. The results showed that superabsorbent hydrogel was responsive to the pH and salts. [ABSTRACT FROM AUTHOR]

Progesterone receptor (PGR) and estrogen receptor alpha (ESRα), which mediate the biological effects of the steroid hormones progesterone and estrogen, play a central role in the establishment and maintenance of pregnancy. The objectives of this study were to detect bovine PGR and ESRα genes polymorphisms and analyze their relationships with the pregnancy rates after embryo transfer and the hormone concentrations at the day of embryo transfer. One reported SNP of PGR G59752C and a novel SNP of ESRα G75935C were analyzed in 132 recipients of Luxi cattle. For the PGR gene, recipients with g.59752 GG and g.59752 GC genotypes had obviously higher pregnancy rates than g.59752 CC genotype. For the ESRα gene, recipients with g.75935 GC and g.75935 CC genotypes had obviously higher pregnancy rates than g.75935 GG genotype. Furthermore, the same tendency was observed for these two genes that the same genotype groups with high pregnancy rates had high progesterone concentration and low estrogen concentration at the day of embryo transfer. These results showed for the first time that PGR G59752C and ESRα G75935C polymorphisms had obvious effects on the pregnancy rates after embryo transfer, and indicated that PGR G59752C and ESRα G75935C polymorphisms could be potential markers for recipient selection of embryo transfer. [ABSTRACT FROM AUTHOR]

This study investigated the protective effects of Lycium barbarum polysaccharide (LBP) on alleviating injury from oxygen-glucose deprivation/reperfusion (OGD/RP) in primary cultured rat hippocampal neurons. Cultured hippocampal neurons were exposed to oxygen-glucose deprivation (OGD) for 2 h followed by a 24 h re-oxygenation. The MTT assay and the lactate dehydrogenase (LDH) release were used to determine the neuron viability. Superoxide dismutase (SOD), Glutathione peroxidase (GSH-PX), malondialdehyde (MDA) were determined by spectrophotometry using commercial kits. Mitochondrial membrane potential (MMP) and the intracellular free calcium concentration ([Ca]) in hippocampal neurons were measured using the confocal laser scanning microscope (CLSM). Treatment with LBP (10-40 mg/l) significantly attenuated neuronal damage and inhibited LDH release in a dose-dependent manner. Furthermore, LBP enhanced activities of SOD and GSH-PX but it decreased their MDA content, inhibited [Ca] elevation and decrease of MMP in ischemia-reperfusion treated hippocampal neurons. These findings suggested that LBP may be a potential neuroprotective agent for cerebral ischemia-reperfusion injury. [ABSTRACT FROM AUTHOR]

The major limitation to the development of embryo transfer technique in cattle is the highly variable between individuals in ovulatory response to FSH-induced superovulation. The objective of this study was to identify a predictor to forecast superovulation response on the basis of associations between superovulation performance and gene polymorphism, variation in the bovine luteinizing hormone/choriogonadotropin receptor (LHCGR) gene was investigated using PCR-single-strand conformational (PCR-SSCP) and DNA sequencing. Four single nucleotide polymorphisms (SNPs) of G51656T, A51703G, A51726G and G51737A were identified at the intron 9 of the LHCGR gene in 171 Chinese Holstein cows treated for superovulation, and evaluated its associations with superovulatory response. Association analysis showed that these four SNPs had significant effects on the total number of ova (TNO) ( P < 0.05). Moreover, the A51703G and A51726G polymorphisms significantly associated with the number of transferable embryos (NTE) ( P < 0.05). In addition, significant additive effect on TNO was detected in polymorphisms of G51656T ( P < 0.05) and A51703G ( P < 0.01), and the A51703G polymorphism also had significant additive effects on NTE ( P < 0.01). These results indicate that LHCGR gene is a potential marker for superovulation response and can be used to predict the most appropriate dose of FSH for superovulation in Chinese Holstein cows. [ABSTRACT FROM AUTHOR]

The common genetic polymorphism for SULT1A1 is Arg213His polymorphism, which may affect the sulfation process of various environmental carcinogens and thus is suggested to be related to susceptibility of several cancers. However, studies on the association between SULT1A1 Arg213His polymorphism and cancer susceptibility are inconsistent. To assess the relationship between Arg213His polymorphism and environmental-related cancers systematically, we performed a meta analysis from 20 case-control studies including 5,915 cases and 7,900 controls. The odds ratios (ORs) and 95% confidence intervals (CIs) were used to estimate the strength of risk, we found a significant association between SULT1A1 Arg213His polymorphism and environment-related cancers (for dominant model: OR 1.22, 95% CI 1.07-1.39, P = 0.003). When stratified by ethnicity, a significant risk was observed in Asian cases, compared with controls (for dominant model: OR 1.69, 95% CI 1.17-2.43, P = 0.005). When we chose only smokers in our analysis, we also found a significantly increased risk between Arg213His polymorphism and susceptibility of environment-related cancers for participants exposed to a smoking environment. In conclusion, SULT1A1 Arg213His polymorphism, ethnicity, smoking may modulate environment-related cancer risk. Studies on gene-gene interactions in the sequential or concurrent metabolic pathway and gene-environment interactions need to be further conducted to explore the susceptibility of cancer occurrence. [ABSTRACT FROM AUTHOR]