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Low temperature is a serious abiotic stress affecting rice production in subtropical and temperate areas. In this study, cold tolerance of rice at the germination and seedling stages were evaluated using one recombinant inbred line (RIL) population derived from a cross between Daguandao ( japonica), with highly cold-tolerant at the seedling stage, and IR28 ( indica), with more cold-tolerant at the germination stage, and the quantitative trait loci (QTL) mapping was conducted using the multiple interval mapping (MIM) approach. Continuous segregation in low temperature germinability (LTG) and cold tolerance at the seedling stage (CTS) were observed among the RIL populations. Most RILs were moderately susceptible or tolerant at the germination stage, but were susceptible at the seedling stage. No significant relationship was found in cold tolerance between the germination and seedling stages. A total of seven QTLs were identified with limit of detection (LOD) >3.0 on chromosomes 3, 8, 11 and 12, and the amount of variation ( R) explained by each QTL ranged from 5.5 to 22.4%. The rice LTG might be regulated by two minor QTLs, with the CTS controlled by one major QTL [ qCTS8.1 (LOD = 16.1, R = 22.4%)] and several minor loci. Among these loci, one simultaneously controls LTG ( qLTG11.1) and CTS ( qCTS11.1). Several cold-tolerance-related QTLs identified in previous studies were found to be near the QTLs detected here, and three QTLs are novel alleles. The alleles from Daguandao at six QTLs increased cold tolerance and could be good sources of genes for cold tolerance. In addition, only one digenic interaction was detected for CTS, with a R value of 6.4%. Those major or minor QTLs could be used to significantly improve cold tolerance by marker-assisted selection (MAS) in rice. [ABSTRACT FROM AUTHOR]

Salt tolerance of rice ( Oryza sativa L.) at the seed germination stage is one of the major determinants for the stable stand establishment in salinity soil. One population of recombinant inbred lines (RILs, F), derived from a cross between a japonica rice landrace tolerant to salt stress and a sensitive indica rice variety, was used to determine the germination traits including imbibition rate and germination percentage under control (water) and salt stress (100 mM NaCl) for 10 days at 30 °C. The multiple interval mapping (MIM) were applied to conduct QTL for the traits. The results showed that seed germination was a quantitative trait controlled by several genes, and strongly affected by salt stress. A total of 16 QTLs were detected in this study, and each QTL could explain 4.6-43.7% of the total phenotypic variance. The expression of these QTLs might be developmentally regulated and growth stage-specific. In addition, only one digenic interaction was detected under salt stress, showing small effect on germination percentage with R 2.7%. Among sixteen QTLs detected in this study, four were major QTLs with R > 30%, and some novel alleles of salt tolerance genes in rice. The results demonstrated that the japonica rice Jiucaiqing is a good source of gene(s) for salt tolerance and the major or minor QTLs identified could be used to improve the salt tolerance by marker-assisted selection (MAS) in rice. [ABSTRACT FROM AUTHOR]

Rice blast is one of the most devastating diseases affecting rice production worldwide. One japonica landrace, Heikezijing, from the Taihu Lake area in China, has been reported to be highly resistant to most of the rice blast isolates collected from China and Japan. To effectively dissect the inheritance of its resistance, a population of recombinant inbred lines (RILs) (F2:8) was constructed from a cross between Heikezijing and Suyunuo, a blast-susceptible cultivar. Nineteen blast isolates from China and Japan were inoculated into 166 RILs and their parents, and 22 quantitative trait loci (QTLs) conferring resistance to these isolates were identified and mapped onto rice chromosomes 1, 7, 9. 11, and 12. Most of the QTLs conferred race-specific resistance to blast. Some QTLs, such as qtl11-5-5, conferred resistance to two or more isolates. One blast-resistant gene cluster, including qtl11-2-2, qtl11-3-1, qtl11-4-1, qtl11-5-5, qtl11-6-1, qtl11-7-5, qtl11-8-2, qtl11-9-2, qtl11-10-4, and qtl11-11-1, was found on the long arm of chromosome 11 in the japonica landrace. These loci offered effective resistance toward as many as 17 isolates, including 16 isolates from seven Chinese race groups and 1 isolate from Japan. The results from this study suggest that the Heikezijing landrace involves a number of genes that are associated with broad-spectrum resistance to rice blast. [ABSTRACT FROM AUTHOR]

Background: Nanocrystalline silver dressings have anti-inflammatory activity, unlike solutions containing Ag+ only, which may be due to dissolution of multiple silver species. These dressings can only be used to treat surfaces. Thus, silver-containing solutions with nanocrystalline silver properties could be valuable for treating hard-to-dress surfaces and inflammatory conditions of the lungs and bowels. This study tested nanocrystalline silver-derived solutions for anti-inflammatory activity. Methods: Inflammation was induced on porcine backs using dinitrochlorobenzene. Negative and positive controls were treated with distilled water. Experimental groups were treated with solutions generated by dissolving nanocrystalline silver in distilled water adjusted to starting pHs of 4 (using CO2), 5.6 (as is), 7, and 9 (using Ca(OH)2). Solution samples were analyzed for total silver. Daily imaging, biopsying, erythema and oedema scoring, and treatments were performed for three days. Biopsies were processed for histology, immunohistochemistry (for IL-4, IL-8, IL-10, TNF-α, EGF, KGF, KGF-2, and apoptotic cells), and zymography (MMP-2 and -9). One-way ANOVAs with Tukey-Kramer post tests were used for statistical analyses. Results: Animals treated with pH 7 and 9 solutions showed clear visual improvements. pH 9 solutions resulted in the most significant reductions in erythema and oedema scores. pH 4 and 7 solutions also reduced oedema scores. Histologically, all treatment groups demonstrated enhanced re-epithelialisation, with decreased inflammation. At 24 h, pMMP-2 expression was significantly lowered with pH 5.6 and 9 treatments, as was aMMP-2 expression with pH 9 treatments. In general, treatment with silver-containing solutions resulted in decreased TNF-α and IL-8 expression, with increased IL-4, EGF, KGF, and KGF-2 expression. At 24 h, apoptotic cells were detected mostly in the dermis with pH 4 and 9 treatments, nowhere with pH 5.6, and in both the epidermis and dermis with pH 7. Solution anti-inflammatory activity did not correlate with total silver content, as pH 4 solutions contained significantly more silver than all others. Conclusions: Nanocrystalline silver-derived solutions appear to have anti-inflammatory/pro-healing activity, particularly with a starting pH of 9. Solutions generated differently may have varying concentrations of different silver species, only some of which are anti-inflammatory. Nanocrystalline silver-derived solutions show promise for a variety of anti-inflammatory treatment applications. [ABSTRACT FROM AUTHOR]

Although photosensitization of titania by organic dyes is one of the conventional ways for visible-light utilization of titania, previous studies have not yet addressed the use of dyes as templates in the synthesis of mesoporous materials, let alone the simultaneous achievement of highly crystalline mesoscopic ordering and visible-light photocatalytic activity. In this work, fourteen commercial synthetic dyes were directly used as structure-directing agents which convert to carbonaceous materials after 400 °C calcination in synthesis of thermally stable mesostructured titania. This in situ carbon enhanced the visible light photocatalytic activities for the degradation of aqueous dyes. The synthesized mesoporous titania samples were characterized by a combination of various physicochemical techniques, such as XRD, SEM, HRTEM, nitrogen adsorption/desorption, TGA–DSC, XPS, diffuse reflectance UV–vis and FT–IR. Most of prepared mesoporous titania photocatalysts exhibited better activity under outside solar light than under artificial UV light, due to the presence of carbonaceous species which were transferred from the dye templates. The reported strategies combine sol-gel chemistry and self-assembly routes directly using dye templates that tune the material's architecture, texture and particularly function, visible-light photocatalysis. [ABSTRACT FROM AUTHOR]

This article deals with the problem of robust stabilisation and H∞ control for a class of uncertain stochastic time-delay system. The parametric uncertainties are real time-varying and norm bounded. The aim is to design a memoryless state-feedback control law such that the closed-loop system are robustly stochastically asymptotically stable in the mean square and the effect of the disturbance input on the controlled output is less than a prescribed level for all admissible parameter uncertainties. New sufficient conditions for the existence of such control law are presented based on the linear matrix inequalities approach. Numerical examples are given to illustrate the effectiveness of the developed techniques. [ABSTRACT FROM AUTHOR]

Hypertrophic scar (HTS) after thermal injury is a dermal fibroproliferative disorder, which leads to considerable morbidity. Previous clinical studies from our laboratory have suggested that interferon-2b (IFN-2b) improves scar quality as a result of the suppression of fibroblast function. More recently, our work has demonstrated that the improvement of scar in patients with HTS after IFN-2b treatment may be associated with a decreased number of fibrocytes and/or altered fibrocyte function. In this study, we report that the improvement of HTS after IFN-2b treatment may be associated with a decrease in angiogenesis. Using immunohistochemistry, we demonstrate an increase in angiogenesis in HTS compared to normal skin, and also show an increase in the expression of vascular endothelial cell growth factor (VEGF) in HTS. Subsequently, we demonstrate a significant reduction in angiogenesis in HTS tissue from patients after treatment with systemic IFN-2b. By using a [3H] thymidine incorporation assay, we demonstrate that IFN-2b suppresses the proliferation of human umbilical vein endothelial cells (HUVECs) in a dose-dependent manner. In addition, IFN-2b inhibits VEGF-induced proliferation and tube formation by using HUVECs. All these effects may be a result of the blocking of VEGF receptor expression on endothelial cells by IFN-2b. Taken together with previous results, the present study suggests that the improvement of scar quality in HTS patients after IFN-2b treatment may also be associated with decreased angiogenesis in HTS. The current in vitro results may provide some insights into the scar improvement that is seen with systemic IFN-2b treatment. [ABSTRACT FROM AUTHOR]

Hypertrophic scar (HTS) following thermal injury is a dermal fibroproliferative disorder that leads to considerable morbidity. Previous clinical studies from our laboratory have suggested that interferon-α2b (IFN-α2b) improves scar quality as a result of suppression of fibroblast functions. Fibrocytes, which constitute a unique cell population, have recently been reported to contribute to wound healing and to a variety of fibrotic conditions, including HTS. Therefore, we hypothesize that improvement of scar in HTS patients after IFN-α2b treatment may be associated with a decreased number of fibrocytes or altered fibrocyte function. Using flow cytometry, immunofluorescent staining, and confocal microscopy, we demonstrate here that the marker protein leukocyte-specific protein 1 (LSP1) is stably expressed by fibrocytes for at least 2 months, whereas other potential fibrocyte markers, such as CD34 and CD45, gradually disappear. Using dual staining immunohistochemistry for LSP1 and procollagen, we demonstrated a significant reduction in numbers of fibrocytes in HTS tissue from patients after treatment with systemic IFN-α2b. IFN-α2b was shown to abolish fibrocyte differentiation from peripheral blood mononuclear cells (PBMCs) in vitroin a dose-dependent fashion. In addition, IFN-α2b inhibits proliferation of fibrocytes and T lymphocytes and reduces transforming growth factor-β(TGF-β)-mediated α-smooth muscle actin (α-SMA) expression in fibrocytes. Taken together with our previous study in which we showed that fibrocytes could indirectly regulate dermal fibroblasts in burn patients, the present study suggests that the improvement of scar quality in HTS patients after IFN-α2b treatment is associated with decreased numbers and activities of fibrocytes. [ABSTRACT FROM AUTHOR]

Polarization and dielectric behavior of Li and Ti co-doped NiO (LTNO) ceramics was investigated. Analysis of the ceramic microstructure and composition indicate that an obvious grain boundary was formed and surrounded the grains, and Ti ions distributed in grains and grain boundaries. The concentration of Ti had a remarkable effect on the dielectric properties of the LTNO ceramics. Positron annihilation spectra measurements implied that a large amount of defects exist in the LTNO ceramic samples. Anomaly polarization–electric field hysteresis loops were observed in the high-permittivity dielectric LTNO ceramics, which are totally different from those for ferroelectric materials and are due to defect-dipoles induced, and electrical conduction effects of samples could also have an influence on the hysteresis loops. The high dielectric constant response of the LTNO ceramics is enhanced partially by the boundary layer capacitor mechanism, and partially by the huge polarization of a large amount of defect dipoles. [ABSTRACT FROM AUTHOR]

The dielectric properties of Na0.5Bi0.5TiO3 (NBT) -based composites incorporating silver particles prepared by sintering at a low temperature of ∼900°C are reported. The dielectric constant increases with the amount of metal silver particles in the measured frequency range (150 Hz to 1 MHz), and could be enhanced up to ∼20 times higher than that of pure NBT ceramics, which was ascribed to the effective electric fields developed between the dispersed particles in the matrix and the percolation effect. Further investigation revealed that the dielectric constant of the composites has weak frequency and temperature dependence (−50°C to +50°C). [ABSTRACT FROM AUTHOR]

The eukaryotic initiation factor 1A(eIF1A) is essential for transferring of the initiator Met-tRNA to 40S ribosomal subunits to form the 40S pre-initiation complex. In present study, we describe the cloning and characterization of two eIF1A genes from rice, which were designated as Oryza sativa eukaryotic initiation factor 1A genes OseIF1A-1 , OseIF1A-2 , respectively. Both rice eIF1As shared high identities in amino acids with eIF1A proteins from other eukaryotes. The mRNA expression analysis revealed that OseIF1A-2 mRNA was much more accumulated than OseIF1A-1 in all tissues but each gene is expressed in root, stem, leaf and flowering spike in high and nearly equal level, and in immature spike in lower level. These results, together with their different location in unrooted phylogenetic tree inferred from amino acid sequences of all known eIF1As, suggested that there are two types of eIF1A genes with different function or different regulation in rice. [ABSTRACT FROM AUTHOR]

The pentose phosphate pathway (PPP) is the important metabolism pathway in plant. In the present study, a cDNA encoding one of the key enzymes of PPP, 6-phosphogluconate dehydrogenase(6PGDH), was isolated from rice and designated as Os6PGDH. The Os6PGDH encoding protein is a cytosolic isoenzyme according to the absence of plastid transit peptide at the N-terminus. The full-length cDNA of 1751 bp encodes 480 amino acids and its putative protein sequence is 94%, 84% and 83% identical to maize, spinach and alfalfa 6PGDHs respectively. Comparison of the cloned mRNA sequence with that of the genomic sequence from the Rice Genome Project showed a simple genomic organization devoid of introns in the translated region of the gene. RT-PCR experiments revealed that Os6PGDH expression was high in inflorescence, low in root and embryos but almost absent in leaves. Furthermore, Os6PGDH was up-regulated in the shoots under salt stress. It is suggested that 6PGDH in plant may play an important role in cell division and salt response. [ABSTRACT FROM AUTHOR]

Here we report a kind of diluted magnetic semiconductor (DMS) system, i.e., Fe-doped NiO. Monophase Ni1-xFexO (x=0–0.02) was synthesized by using a chemical coprecipitation method and post-thermal decomposition processing. Pure NiO without Fe doped is antiferromagnetic. The results demonstrated the samples with Fe doped were ferromagnetic at room temperature, which is stronger than most DMS oxide systems, e.g., Mn or Ni-doped ZnO, and Co-doped TiO2 reported recently. The effect of Fe doping was discussed and relevant mechanism was proposed, by comparing with previous studies of finite size effect in NiO nanoparticles and other DMS systems. [ABSTRACT FROM AUTHOR]

High-permittivity dielectric NiO-based ceramics co-doped with Li and Al (LANO) have been prepared by a traditional solid-state synthesis. Analyses of the ceramic microstructure and composition indicate that Al ions are distributed in grain boundaries, and that uniform boundaries indexed as NiAl2O4 surround the grains. The concentration of Al has a remarkable effect on the dielectric properties of the LANO ceramics. The dielectric constant remains almost constant (∼104–105) at low frequency and has a steplike decrease toward higher frequencies. The high-dielectric-constant response of the LANO ceramics is mainly enhanced by Maxwell–Wagner polarization. [ABSTRACT FROM AUTHOR]

Heikezijing, a japonica rice landrace from the Taihu region of China, exhibited broad-spectrum resistance to more than 300 isolates of the blast pathogen (Magnaporthe oryzae). In our previous research, we fine mapped a broad-spectrum resistance gene, Pi-hkI, in chromosome 11. In this research, 2010-9(G 1), one of the predominant races of blast in the Taihu Lake region of China, was inoculated into 162 recombinant inbred lines (RIL) and two parents, Heikezijing and Suyunuo, for mapping the resistance-blast quantitative trait loci (QTL). Three QTL (Lsqtl4-1, Lsqtl9-1, and Lsqtlll-1) associated with lesion scores were detected on chromosomes 4, 9, and 11 and two QTL (Lnqtll-I and Lnqtl9-1) associated with average lesion numbers were detected on chromosomes 1 and 9. The QTL Lsqtl9-1 conferring race-specific resistance to 20I0-9(GI) at seedling stages showed logarithm of the odds scores of 9.10 and phenotypic variance of 46.19% and might be a major QTL, named Pi-hk2. The line RIL84 with Pi-hk2 derived from a cross between Heikezijing and Suyunuo was selected as Pi-hk2 gene donor for developing fine mapping populations. According to the resistance evaluation of recombinants of three generations (BC1F2, BC1F3, and BC1F4), Pi-hk2 was finally mapped to a 143-kb region between ILP-19 and RM24048, and 18 candidate genes were predicted, including genes that encode pleiotropic drug resistance protein 4 (n = 2), WRKY74 (n = 1), cytochrome b5-like heme/steroid-binding domain containing protein (n = 1), protein kinase (n = I), and ankyrin repeat family protein (n = I). These results provide essential information for cloning of Pi-hk2 and its potential utility in breeding resistant rice cultivars by marker-assisted selection. [ABSTRACT FROM AUTHOR]

One Japonica rice landrace, Heikezijing, from the Taihu Lake region of China, exhibits broad-spectrum resistance to rice blast. As characterized in our previous research, a main-effect resistance (R) gene, Pi-hkl, in Heikezijing against five isolates (GD10-279a, JS2004-141-1, JS2004-185. JS90-78, and Hokul) was roughly mapped on the long arm of chromosome 11. To fine map Pi-hkl, one recombinant inbred line (RIL), RIL72 (F2;8), from the cross between Heikezijing and blast-susceptible variety Suyunuo, was further crossed and backcrossed with Suyunuo to produce a BQF2 population of 477 individuals. Inoculation experiments with the representative isolate Hoku 1 indicated that RIL72 carries a single dominant R gene for blast resistance. With the help of advanced BQF3 (915 plants), BQF4 (4,459 plants), and BCjF5 (2,000 plants) mapping populations, Pi-hkl was finally mapped to a 107-kb region between molecular markers P3586 and ILP3, and co-segregated with the markers P4098, RM7654, and P4099. By sequence analysis of Heikezijing bacterial artificial chromosome clones covering Pi-hkl region, 16 predicted genes were identified within this region, including three nucleotide-binding site leucine-rich repeat candidate genes. These results provide essential information for cloning of Pi-hkl and its application in rice breeding for broad-spectrum blast resistance by marker-assisted selection. [ABSTRACT FROM AUTHOR]

In this study, we constructed a two-dimensional ventricular tissue sheet with cellular electrophysiology modified from the Ten Tusscher 2006 Model. Heterogeneity was created by dividing the tissue into endocardium, midmyocardium and epicardium, further enhanced by a central ischemic zone. Subsequently, we investigated how electrophysiological heterogeneity affects re-entry initiation and maintenance in this tissue. Furthermore, we analyzed the vulnerable window (VW) under several conditions and concluded that heterogeneity across various myocardia expands the VW further than the monolayer myocardium model does.

Cardiac potential gradient distribution directly affects defibrillation efficacy, and the electrode configuration that ensures optimal distribution is yet to be determined. In this study, a rabbit ventricular finite element conductor model containing blood perfusion in ventricular cavities was developed. The electric field was solved on the model by using 95% myocardial volume potential gradient higher than 5 V/cm as the successful defibrillation threshold (DFT). Multiple epicardial electrodes (MEE) protocols and a SCAN protocol were used to identify the optimum defibrillation method. Results showed that when using the SCAN protocol, DFT energy reduced to 4.3% that of the control group which had the traditional implantable cardioverter defibrillator current path. Rapidly switching scanning stimuli generated using MEE pairs is a promising low-energy defibrillation method. For multiple electrodes defibrillation, the distribution of the electrode pairs determine the defibrillation efficacy, and the counteraction effect has negative effect on defibrillation. These findings can provide suggestions for clinical applications.