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Abstract All related research nowadays are devoted to build ROM of aerodynamic forces induced by vibration of blades or wings. There is no discussion of ROMs of the aerodynamic forces of the blades corresponding to upstream wakes, which is more important to turbine machines' safety. In this paper, a spline Volterra ROM method is proposed to predict the blades' aerodynamic forces induced by the upstream wakes to fasten the blade–wake interaction analysis in turbine machine design. Traveling wave method is applied to simplify the inputs representing the upstream wakes. The kernels of the Volterra ROM are expressed in spline to reduce the number of parameters to be identified. The coefficients of the spline kernels are identified by minimizing the difference between ROM results and CFD data. The ROM method is used to predict a blade's aerodynamic forces under an actual wake. The results show that the ROM can capture most information of the aerodynamic forces due to the wake. [ABSTRACT FROM AUTHOR]

In the present study, mesenchymal stem cells (MSCs) were transplanted into the brain of rats following cardiopulmonary resuscitation (CPR) by three different methods: Direct stereotaxic injection into the lateral cerebral ventricle (LV), intra-carotid administration (A), and femoral venous infusion (V). The three different methods were compared by observing the effects of MSCs on neurological function following global cerebral hypoxia-ischemia, in order to determine the optimum method for MSC transplantation. MSCs were transplanted in groups A, V and LV following the restoration of spontaneous circulation. Neurological deficit scale scores were higher in the transplantation groups, as compared with the control group. Neuronal damage, brain water content and serum levels of S100 calcium-binding protein B were reduced in the hippocampus and temporal cortex of the transplantation groups, as compared with the control rats following resuscitation. MSCs were able to migrate inside the brain tissue following transplantation, and were predominantly distributed in the hippocampus and temporal cortex where the neurons were vulnerable during global cerebral ischemia. These results suggest that transplantation of MSCs may notably improve neurological function following CPR in a rat model. Of the three different methods of MSC transplantation tested in the present study, LV induced the highest concentration of MSCs in brain areas vulnerable to global cerebral ischemia, and therefore, produced the best neurological outcome. [ABSTRACT FROM AUTHOR]

With the accuracy limitation of some transfer methods in the self-parallel fluid–structure interfaces, a data transfer method is proposed by an ISOMAP (Isometric Mapping) nonlinear dimensionality reduction. Through this new method, the data transfer problem of the self-parallel interfaces is solved. Example of a 3D turbine blade shows that the proposed method can improve the transfer accuracy in the non-matching meshes. [ABSTRACT FROM AUTHOR]

Background: Recently, an infant and child feeding index (ICFI) constructed on brief recalls of breastfeeding, feeding frequency and food diversification was assumed to provide long-term prediction about child feeding practices. The aim of this study was to investigate the association between the cross-sectional ICFI (CS-ICFI) or longitudinal ICFI (L-ICFI) and child anthropometric indices in downtown Shanghai, China. Methods: The prospective cohort study included 180 infants aged 5-7 mo with their main caregivers who were visited 3 times every 6 months over 12 months. A CS-ICFI was constructed for each visit by using data on feeding practices based on 24-h and 7-d recalls. An L-ICFI was constructed with use of the 3 CS-ICFIs. The associations between ICFI and length-for-age z score (LAZ), weight-for-age z score (WAZ), and weight-for-length z score (WLZ) were examined. The stability of the CS-ICFI was assessed by using repeatability coefficient (RC). Results: The L-ICFI was positively associated with LAZ and WAZ at Visit 3(beta = 0.151, P = 0.040 and beta = 0.173, P = 0.024, respectively). Moreover, the CS-ICFI at Visit 1 was positively associated with LAZ, WAZ and WLZ (beta = 0.160, P = 0.029; beta = 0.191, P = 0.009; beta = 0.176, P = 0.020) at Visit 3, and the CS-ICFI at Visit 3 was also positively associated with LAZ (beta = 0.176, P = 0.016). Stability of the CS-ICFI was shown by the value of 0.14 (95% CI: 0.07, 0.31) of the RC, which differed significantly from 0 (P<0.05). Conclusions: The ICFI constructed on brief recalls based on cross-sectional studies can be used to evaluate the effects of child feeding practice on child growth. [ABSTRACT FROM AUTHOR]

Isomeric polymers [Cd2(mbt)4] n and [Cd(mbt)2] n (mbt = mercaptobenzothiazole) are investigated. The complex {[Cd(μ-η2-C7H4NS2)2][Cd(μ-η2-C7H4NS2) (μ-η3-C7H4NS2)]} n is formed by the reaction of Cd(NO3)2·4H2O with 2-Hmbt in the presence of H2biim in EtOH/H2O. The complex crystallizes in the orthorhombic space group Pca2(1), where a = 21.892(2), b = 9.8994(11), c = 14.8687(15) Å, α = 90, β = 90, γ = 90º, V = 3,222.3(6) Å3, and Z = 4. The two Cd atoms, one exhibits a CdN2S2 tetrahedral geometry and the other exhibits a distorted CdN2S3 trigonal bipyramidal geometry, are linked by bridging–chelating mbt and bridging mbt ligands. The infinite 1D polymer chains complex {[Cd(μ-η2-C7H4N2S2)2][Cd(μ-η2-C7H4NS2) (μ3-η2-C7H4NS2)]} n is formed by the reaction of Cd(NO3)2·4H2O, 2-Hmbt in the present of H2biim, which contains a CdN2S2 tetrahedral geometry and a distorted CdN2S3 trigonal bipyramidal geometry.[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

The accumulation of plasma advanced oxidation protein products (AOPPs) is prevalent in diverse disorders such as diabetes, metabolic syndromes, and chronic kidney disease. To study whether accumulated AOPPs have an important role in the progression of proteinuria and glomerulosclerosis, we chronically treated normal Sprague–Dawley rats with AOPP-modified rat serum albumin. Podocyte apoptosis was significantly increased coincident with the onset of albuminuria and preceded significant losses of glomerular podocytes. Increasing the amount of AOPPs in the media of conditionally immortalized podocytes rapidly triggered the production of intracellular superoxide by activation of NADPH oxidase and this, in turn, led to an upregulation of p53, Bax, caspase 3 activity, and apoptosis. Chronic inhibition of NADPH oxidase by apocynin prevented podocyte apoptosis, ameliorated podocyte depletion, and decreased albuminuria in AOPP-challenged rats. Our study demonstrates that accumulation of AOPPs promotes NADPH oxidase–dependent podocyte depletion by a p53-Bax apoptotic pathway both in vivo and in vitro. [ABSTRACT FROM AUTHOR]

Aluminum (Al) toxicity is a major constraint for wheat production in acidic soils. An Al resistance gene on chromosome 4DL that traces to Brazilian wheat has been extensively studied, and can provide partial protection from Al damage. To identify potentially new sources of Al resistance, 590 wheat accessions, including elite wheat breeding lines from the United States and other American and European countries, landraces and commercial cultivars from East Asia, and synthetic wheat lines from CIMMYT, Mexico, were screened for Al resistance by measuring relative root elongation in culture with a nutrient solution containing Al, and by staining Al-stressed root tips with hematoxylin. Eighty-eight wheat accessions demonstrated at least moderate resistance to Al toxicity. Those selected lines were subjected to analysis of microsatellite markers linked to an Al resistance gene on 4DL and a gene marker for the Al-activated malate transporter ( ALMT1) locus. Many of the selected Al-resistant accessions from East Asia did not have the Al-resistant marker alleles of ALMT1, although they showed Al resistance similar to the US Al-resistant cultivar, Atlas 66. Most of the cultivars derived from Jagger and Atlas 66 have the Al-resistant marker alleles of ALMT1. Cluster analysis separated the selected Al-resistant germplasm into two major clusters, labeled as Asian and American–European clusters. Potentially new germplasm of Al resistance different from those derived from Brazil were identified. Further investigation of Al resistance in those new germplasms may reveal alternative Al-resistance mechanisms in wheat. [ABSTRACT FROM AUTHOR]

Quantitative trait loci (QTL) for wheat resistance to aluminum (Al) toxicity were analyzed using simple sequence repeats (SSRs) in a population of 192 F6 recombinant inbred lines (RILs) derived from a cross between an Al-resistant cultivar, Atlas 66 and an Al-sensitive cultivar, Chisholm. Wheat reaction to Al was measured by relative root growth and root response to hematoxylin stain in nutrient-solution culture. After screening 1,028 SSR markers for polymorphisms between the parents and bulks, we identified two QTLs for Al resistance in Atlas 66. One major QTL was mapped on chromosome 4D that co-segregated with the Al-activated malate transporter gene ( ALMT1). Another minor QTL was located on chromosome 3BL. Together, these two QTLs accounted for about 57% of the phenotypic variation in hematoxylin staining score and 50% of the variation in net root growth (NRG). Expression of the minor QTL on 3BL was suppressed by the major QTL on 4DL. The two QTLs for Al resistance in Atlas 66 were also verified in an additional RIL population derived from Atlas 66/Century. Several SSR markers closely linked to the QTLs were identified and have potential to be used for marker-assisted selection (MAS) to improve Al-resistance of wheat cultivars in breeding programs. [ABSTRACT FROM AUTHOR]

This study presents a multi-round shape optimization method based on the aerodynamic reduced order model. In this method, each optimization round employs the first-order Taylor reduced order model to provide aerodynamic characteristics in the local design space around the baseline point. At the end of each optimization round, the baseline point moves toward the optima and a new reduced order model is built at the new baseline point for the next optimization round. In this way, the provided method explores the whole design space. The NACA0012 airfoils in subsonic and transonic flows are used to verify the method with the lift-drag ratio as optimization objective. The design parameters are the shape control parameters of the airfoil. The optimization algorithm is a genetic algorithm. After a total of 20 simulations by two rounds of optimizations, the lift-drag ratios increase from 0 to 25 and from 0 to 8 in the subsonic case and transonic case, respectively. An additional trick was suggested for addressing shockwave effect in the transonic case, in which the influence of the airfoil shape on the aerodynamic forces is divided into the following two parts: the smoothed part to address the influence of the shape on the smooth aerodynamic distribution, and the shockwave part to address the influence of the shape on shockwave strength, shockwave position, and their effect on the aerodynamic distribution. The optimizations of the airfoils in subsonic and transonic flows yield different trends. The results of the subsonic case tend to increase the airfoil curvature to increase the lift-drag ratio. The results of the transonic case tend to move the upper surface shockwave to the trailing edge, while moving the lower surface shockwave to the leading edge. Independent of the case, the provided optimization method can properly address the resulting trends and increase the efficiency of the optimization. [ABSTRACT FROM AUTHOR]

Chemical functionalization is a promising approach to controllably manipulate the characteristics of graphene. Here, we designed ris-dienes, featuring two dihydronaphthalene backbones, to decorate a graphene surface via Diels--Alder (DA) click reaction. The installation of a diene moiety into a nonplanar molecular structure to form cis-conformation enables a rapid (~5 min) DA reaction between graphene and diene groups. Patterned graphene of sub-micrometer resolution can be obtained by easily soaking poly(methyl methacrylate)- masked graphene in solution of hydroxyl-substituted cisdiene at room temperature. The functionalization degree can be further controlled by carrying out the reaction at higher temperature. The present result gives important insight into the effect of molecular conformation on the graphene functionalization process, and provides an effective and facile method for graphene functionalization. [ABSTRACT FROM AUTHOR]

Cerebral ischemia injury is a primary cause of human death and long-term disability. We know that the cerebral edema induced by ischemia injury has a fatal effect on humans, which is the main cause of death for cerebral ischemia because it produces elevated intracranial pressure that leads to secondary brain damage, such as further impaired vascular perfusion and herniation of brain. Therefore, reducing the severity of brain edema has become the main therapeutic strategy for the treatment of CI. However, current treatment options for brain edema are limited and problematic. Therefore, finding novel strategies for overcoming this problem is crucial. Numerous studies demonstrated that cerebral edema may be attenuated via the regulation of AQP4 expression, thus initiating a novel therapeutic strategy against this possibly fatal condition. This review focuses on the role of AQP4 in ischemic brain edema, and its prospect as a therapeutic target. [ABSTRACT FROM AUTHOR]

BACKGROUND: Partial pressure of end-tidal carbon dioxide (PETCO2) has been used to monitor the effectiveness of precordial compression (PC) and regarded as a prognostic value of outcomes in cardiopulmonary resuscitation (CPR). This study was to investigate changes of PETCO2 during CPR in rats with ventricular fi brillation (VF) versus asphyxial cardiac arrest. METHODS: Sixty-two male Sprague-Dawley (SD) rats were randomly divided into an asphyxial group (n=32) and a VF group (n=30). PETCO2 was measured during CPR from a 6-minute period of VF or asphyxial cardiac arrest. RESULTS: The initial values of PETCO2 immediately after PC in the VF group were significantly lower than those in the asphyxial group (12.8±4.87 mmHg vs. 49.2±8.13 mmHg, P=0.000). In the VF group, the values of PETCO2 after 6 minutes of PC were significantly higher in rats with return of spontaneous circulation (ROSC), compared with those in rats without ROSC (16.5±3.07 mmHg vs. 13.2±2.62 mmHg, P=0.004). In the asphyxial group, the values of PETCO2 after 2 minutes of PC in rats with ROSC were significantly higher than those in rats without ROSC (20.8±3.24 mmHg vs. 13.9±1.50 mmHg, P=0.000). Receiver operator characteristic (ROC) curves of PETCO2 showed significant sensitivity and specificity for predicting ROSC in VF versus asphyxial cardiac arrest. CONCLUSIONS: The initial values of PETCO2 immediately after CPR may be helpful in differentiating the causes of cardiac arrest. Changes of PETCO2 during CPR can predict outcomes of CPR. [ABSTRACT FROM AUTHOR]

The parabolic equation (PE) method and finite-difference time-domain (FDTD) method are combined to predict long-range Loran-C additional secondary factors (ASFs) in situations with near-source complex topography. The non-uniform FDTD method is employed in the complex source region, while the PE method is used for propagation over smooth terrain to a long distance. By using the advantages of each algorithm, the hybrid FDTD--PE approach is capable of modelling the near-source topographic details, while saving much computational resources as compared to a full FDTD solution. Numerical results along several paths are used to validate the hybrid algorithm. Furthermore, the hybrid method is applied to analyse the effect of near-source topographic complexities, including non-flat land, land--sea transition, and island (cliff)--sea transition, on the navigational coverage for the planning of the Loran-C systems. [ABSTRACT FROM AUTHOR]

Background: Paroxetine, a selective serotonin reuptake inhibitor for counteracting depression, has been recently suggested as having a role in prevention of dopaminergic neuronal degeneration in substantia nigra, a hallmark of Parkinson's disease (PD). The pathogenesis of this type of neurological disorders often involves the activation of microglia and associated inflammatory processes. Thus in this study we aimed to understand the role of paroxetine in microglia activation and to elucidate the underlying mechanism(s). Methods: BV2 and primary microglial cells were pretreated with paroxetine and stimulated with lipopolysaccharide (LPS). Cells were assessed for the responses of pro-inflammatory mediator and cytokines, and the related signaling pathways were evaluated and analyzed in BV2 cells. Results: Paroxetine significantly inhibited LPS-induced production of nitric oxide (NO) and pro-inflammatory cytokines such as TNF-α and IL-1β. Further analysis showed inducible nitric oxide synthase (iNOS) and mRNA expression of TNF-α and IL-1β were attenuated by paroxetine pretreatment. Analyses in signaling pathways demonstrated that paroxetine led to suppression of LPS-induced JNK1/2 activation and baseline ERK1/2 activity, but had little effect on the activation of p38 and p65/NF-κB. Interference with specific inhibitors revealed that paroxetine-mediated suppression of NO production was via JNK1/2 pathway while the cytokine suppression was via both JNK1/2 and ERK1/2 pathways. Furthermore, conditioned media culture showed that paroxetine suppressed the microglia-mediated neurotoxicity. Conclusions: Paroxetine inhibits LPS-stimulated microglia activation through collective regulation of JNK1/2 and ERK1/2 signaling. Our results indicate a potential role of paroxetine in neuroprotection via its anti-neuroinflammatory effect besides targeting for depression. [ABSTRACT FROM AUTHOR]

Abstract: Background: The organic solvent solution immersion method was often used to achieve the loading of the drugs into mesoporous silica, but the drugs that have loaded into the pores of the mesoporous silica would inevitable migrate from the inside to the external surface or near the outside surface during the process of drying. Hence, it often leads to the pores of mesoporous materials not be fully utilized, and results in a low drug loading efficiency and a fast releasing rate. Objective: The purpose of this study was to develop a novel drug loading strategy to avoid soluble component migration during the process of drying, then, to prepare poorly water-soluble drug mesoporous silica microparticles with higher drug loading efficiency and longer sustained-release time. Method: Ibuprofen was used as model drug. The microparticles were prepared by a novel method based on mesoporous silica and supercritical fluid (SCF) technique. The drug-loaded mesoporous silica microparticles prepared by SCF technique were analyzed by thermogravimetric analysis (TGA), N2 adsorption/desorption, scanning electron microscopy (SEM), powder X-ray diffraction (XRD) and differential scanning calorimetry (DSC). In vitro releasing study was used to evaluate the sustained-release effect of the drug-loaded microparticles. Results: By virtue of the high diffusibility and the high dissolving capacity of the supercritical carbon dioxide (SCF-CO2), the poorly water-soluble drugs, ibuprofen, entered the pores of the mesoporous silica. The amount and the depth of ibuprofen entered the pores of the mesoporous silica by SCF technique were both larger than those by the solution immersion method. It was found that ibuprofen loaded into the mesoporous silica by SCF technique was amorphous and the largest amount of the ibuprofen loaded into the mesoporous silica by SCF technique could reach 386mg/g (w/w, ibuprofen/SiO2), it was more than that by the solution immersion method. In vitro releasing study showed that the sustained-release effect of ibuprofen in the samples prepared by SCF technique was 50% in 15min and 90% in 60min. It was longer than that prepared by the solution immersion method. Conclusion: Present study showed that sustained-release poorly water-soluble drug mesoporous silica microparticle based on SCF technique has twofold advantages. One is the larger drug loading amount in internal pores of the mesoporous silica, the other is the longer drug releasing time. [Copyright &y& Elsevier]

lntercropping, which grows at least two crop species on the same pieces of land at the same time, can increase grain yields greatly. Legume-grass intercrops are known to overyield because of legume nitrogen fixation. However, many agricultural soils are deficient in phosphorus. Here we show that a new mechanism of overyielding, in which phosphorus mobilized by one crop species increases the growth of a second crop species grown in alternate rows, led to large yield increases on phosphorus-deficient soils. In 4 years of field experiments, maize (Zea mays L.) overyielded by 43% and faba bean (Vicia faba L.) overyielded by 26% when intercropped on a low-phosphorus but high-nitrogen soil. We found that overyielding of maize was attributable to below-ground interactions between faba bean and maize in another field experiment. Intercropping with faba bean improved maize grain yield significantly and above-ground biomass marginally significantly, compared with maize grown with wheat, at lower rates of P fertilizer application (<75 kg of P2O5 per hectare), and not significantly at high rate of P application (>112.5 kg of P2O5 per hectare). By using permeable and impermeable root barriers, we found that maize overyielding resulted from its uptake of phosphorus mobilized by the acidification of the rhizosphere via faba bean root release of organic acids and protons. Faba bean overyielded because its growth season and rooting depth differed from maize. The large increase in yields from intercropping on low-phosphorus soils is likely to be especially important on heavily weathered soils. [ABSTRACT FROM AUTHOR]