Search

Neuroinflammation is closely related to prognosis in ischemic stroke. Microglia are the main immune cells in the nervous system. Under physiological conditions, microglia participate in clearance of dead cells, synapse pruning and regulation of neuronal circuits to maintain the overall health of the nervous system. Once ischemic stroke occurs, microglia function in the occurrence and progression of neuroinflammation. Therefore, the regulation of microglia-mediated neuroinflammation is a potential therapeutic strategy for ischemic stroke. The anti-inflammatory activity of gypenosides (GPs) has been confirmed to be related to the activity of microglia in other neurological diseases. However, the role of GPs in neuroinflammation after ischemic stroke has not been studied. In this study, we investigated whether GPs could reduce neuroinflammation by regulating microglia and the underlying mechanism through qRT-PCR and western blot. Results showed that GPs pretreatment mitigated blood–brain barrier (BBB) damage in the mice subjected to middle cerebral artery occlusion (MCAO) and improved motor function. According to the results of immunofluorescence staining, GPs pretreatment alleviated neuroinflammation in MCAO mice by reducing the number of microglia and promoting their phenotypic transformation from M1 to M2. Furthermore, GPs pretreatment reduced the number of astrocytes in the penumbra and inhibited their polarization into the A1 type. We applied oxygen and glucose deprivation (OGD) on BV2 cells to mimic ischemic conditions in vitro and found similar effect as that in vivo. At the molecular level, the STAT-3/HIF1-α and TLR-4/NF-κB/HIF1-α pathways were involved in the anti-inflammatory effects of GPs in vitro and in vivo. Overall, this research indicates that GPs are potential therapeutic agents for ischemic stroke and has important reference significance to further explore the possibility of GPs application in ischemic stroke. [ABSTRACT FROM AUTHOR]

An Er:Y3Ga5O12 crystal doped with 30 at% Er3+ was grown by the Czochralski method. The crystal structure and component, thermal and spectroscopic properties are studied systematically. The laser performance of a Φ 3 mm × 66 mm Er:YGG crystal was investigated with LD side-pumped method in the CW mode. The maximum output power of 7.25 W is much higher than that has been realized in the LD end-pumped Er:YGG crystal. The results indicate that the Er:YGG crystal is an ideal material to realize 3 μm laser and the LD side-pumping is a preferred approach to achieve high-power CW laser. [ABSTRACT FROM AUTHOR]

The Er:BGSO polycrystals with different Er3+ ions doping concentrations were successfully prepared by solid-state synthesis method. The phase and structure parameters of these crystals were investigated systematically. The calculation of DFT proves that Bi4(Ge0.5Si0.5)3O12 is the indirect-bandgap material with a bandgap of 3.86 eV. Bi4(Ge0.5Si0.5)3O12 doped with 2 at.% Er3+ ions can suppress the effect of up-conversion luminescence (UCL) effectively, and its stimulated emission cross-section and fluorescence lifetime at 1.5 μm are 2.25 × 10−20 cm2 and 5.19 ms, respectively. In addition, the luminescence of the crystal in the C-band is not sensitive to temperature. The high luminescence intensity, wide emission band, and proper thermal stability indicate that 2 at.%Er:Bi4(Ge0.5Si0.5)3O12 is a potential ideal gain medium of C-band laser. [ABSTRACT FROM AUTHOR]

Er,Pr:Y2.8Sc1Al4.2O12 (Er,Pr:YSAG) crystal has been successfully grown by the Czochralski method. The FWHM of XRC is 0.050°, indicating the high crystalline quality. Besides, thermal conductivity of the crystal is 5.76 W/mK, which is higher than lots of other heavily Er3+ doped crystals meaning the great potential in solid-laser gain media application. Luminescence characters of the crystal at 3 μm are investigated in detail to determine the laser generation potential. An intensive reduce is occurring on the fluorescence lifetimes of 4I13/2 energy level (0.75 ms) of Er3+ ions after Pr3+ ions co-doped, giving the enormous promotion on the multi-wavelength laser generation at 3 μm. Besides, the as-grown Er,Pr:YSAG crystal realizes the dual-wavelength laser generation at 2694 and 2825 nm for the first time, and an average laser power of 235 mW is realized. The M2 factor is used to quantify the laser output beam quality, which value are 1.65/1.56 along x and y axis, meaning a high-brightness laser generation of Er,Pr:YSAG crystal at 3 μm. [ABSTRACT FROM AUTHOR]

Arachidonic acid (AA) signaling pathway is an important constituent of inflammatory processes. In our previous study, it was found that dihydro-stilbene gigantol relieved hepatic inflammation in mice with CCl4-induced acute liver injury. This study aimed to investigate the involvement of arachidonate metabolic cascade in this process. Our results showed CCl4 activated AA metabolism with the evidence of cPLA2 phosphorylation, which was dependent on the MAPK/JNK activation. Pretreatment with JNK inhibitor SU3327 or gigantol abolished the cPLA2 activation, along with the attenuation of liver damage. Besides, gigantol markedly decreased immune cells activation. Metabolomic analysis revealed that gigantol universally reversed the upregulation of major AA metabolites in injured mouse livers induced by CCl4, especially 12-hydroxyeicosatetraenoic acid (12-HETE). Gigantol also decreased the mRNA and protein expression of platelet-, and leukocyte-type 12-lipoxxygenase (LOX) in the liver. Furthermore, pan-LOX inhibitor nordihydroguaiaretic acid (NDGA) and specific 12-LOX inhibitors baicalein and ML351 attenuated the liver injury to the same extent as gigantol. Overall, our study elucidated a comprehensive profile of AA metabolites during hepatic inflammation caused by CCl4, highlighting the role of 12-LOX-12-HETE pathway in this process. And gigantol alleviated liver inflammation partly through inhibiting the JNK/cPLA2/12-LOX pathway. [ABSTRACT FROM AUTHOR]

For the first time, we present a passively Q-switched 1060 nm Nd:GSAG laser using a two-dimensional molybdenum disulfide (MoS2) nanosheet as saturable absorber. We investigate in detail the output characteristics of this laser such as average output power, pulse repetition rate, pulse width, pulse energy, and pulse peak power. [ABSTRACT FROM AUTHOR]

In this paper, we demonstrate for the first time a doubly Q-switched pulsed laser, using a novel Nd:Gd0.69Y0.3NbO4 mixed crystal and acousto-optical (AO) Q-switch and Cr4+:YAG saturable absorber. Compared to purely AO Q-switched lasers, the simultaneous use of AO Q-switches and Cr4+:YAG saturable absorbers provides the generation of a shorter pulse. We investigated in detail the output characteristics of pulsed Nd:Gd0.69Y0.3NbO4 lasers. [ABSTRACT FROM AUTHOR]

Reducing energy consumption for machining operations is a significant research in the manufacturing sector. However, energy-efficient machining oriented to process planning systems is still a challenge. This work uses data structures of Standard for the Exchange of Product model data-Numerical Control (STEP-NC) to develop an energy-efficient process planning system for prismatic parts. A framework of energy-efficient process planning system, consisting of human machine interface, data operation module, and core module, is proposed. The implementation of the system is given, where the core module comprising energy consumption model, ontology, and optimization process is illustrated in details. A test part with typical manufacturing features compliant with STEP-NC is utilized to verify the developed system. The result shows that the process planning system could generate energy-efficient machining scheme with STEP-NC Part21 file or G/M code, which is propitious to the requirement of low energy demand manufacturing. [ABSTRACT FROM AUTHOR]

In this letter, we demonstrate for the first time a doubly Q-switched 1,066 nm pulsed laser using a novel Nd:Gd0.69Y0.3TaO4 mixed crystal. Compared to purely acousto-optical (AO) Q-switched, the simultaneous use of AO Q-switch and Cr4+:YAG saturable absorber can provide the generation of shorter pulses. We investigate the pulsed laser performance at two modulated repetition rates of 10 and 20 kHz. [ABSTRACT FROM AUTHOR]

We demonstrate a diode-pumped acousto-optically (A-O) Q-switched 1,066 nm laser with a novel Nd:Gd0.69Y0.3TaO4 mixed crystal. At a modulation repetition rate of 10 kHz and an absorbed pump power of 15 W, the pulsed laser output characteristics are: average output power 2.41 W, pulse width 27.2 ns, pulse energy 241 μJ, and pulse peak power 8.86 kW. At a modulation repetition rate of 20 kHz and an absorbed pump power of 15 W, the characteristics are: average output power 2.68 W, pulse width 30.1 ns, pulse energy 134 μJ, and pulse peak power 4.45 kW. [ABSTRACT FROM AUTHOR]

We demonstrate for the first time a Cr4+:YAG passively Q-switched 1066 nm pulse-burst laser under 879 nm direct pump with a novel Nd:Gd0.69Y0.3NbO4 crystal. The output laser characteristics with different pump repetition rates and different Cr4+:YAG initial transmission are studied. Without the Cr4+:YAG, we obtain a maximum output energy of 2.55 mJ at an absorbed pump energy of 5.79 mJ with the highest 48% slope efficiency. The pulse-burst laser contains a maximum of 7 pulses for a Cr4+:YAG initial transmission of 55% and a pump repetition rate of 1 kHz. The single-pulse energy and narrowest pulse width reach 160 μJ and 5.5 ns at 38.2 kHz, with a peak power of 32 kW. [ABSTRACT FROM AUTHOR]

LnNbO4 (Ln = Y, Gd and Lu) is a type of material that can be used as both outstanding self-activated phosphor and laser host has generated significant interests. However, their electronic structures and optical properties still require elucidation. To solve this intriguing problem, firstly, YNbO4 and LuNbO4 polycrystalline with monoclinic crystal structure were prepared by traditional high-temperature solid-state reaction method and their structure and luminescent properties were characterized in experiment. Additionally, their CIE chromaticity coordinate were presented to illustrate the luminescent color and the chromaticity coordinates for YNbO4 and LuNbO4 are x = 0.1581, y = 0.0725 and x = 0.1581, y = 0.0753, respectively. Secondly, systematic theoretical calculations based on density functional theory method were carried out on them and their band structures, density of states as well as optical properties were obtained in theoretical. The calculated band gap for YNbO4 and LuNbO4 are 4.101 and 4.214 eV, respectively. Lastly, a comparison between the experimental and calculated band gap and refractive index was conducted. The good coincident between them indicating the calculated results are reliable. Therefore, all of the obtained results could provide an essential understanding of LnNbO4 materials. [ABSTRACT FROM AUTHOR]

A novel mixed laser crystal of Nd:GdLaNbO (Nd:GLNO) was grown successfully by conventional Czochralski method. The unit cell parameters were obtained by Rietveld refinement method. The density of the as-grown crystal was measured by Archimedean buoyancy method and calculated in theory. Absorption spectrum of Nd:GLNO crystal was recorded at room temperature, and 11 absorption peaks were assigned. The defects of Nd:GLNO crystal were revealed by using chemical etching method with phosphoric acid as etchant. The mechanical properties (including hardness, yield strength, elastic stiffness constant, fracture toughness and brittleness index) were systemically estimated based on Vickers hardness test. All these obtained results play a quite important role in further investigation of Nd:GLNO crystal. [ABSTRACT FROM AUTHOR]

A Nd-doped GdNbO single crystals have been grown successfully using the Czochralski technique. The chemical etching method was employed to study the defects in the structural morphology of Nd:GdNbO crystal with phosphoric acid etchant. Mechanical properties (such as hardness, yield strength, fracture toughness, and brittle index) of the as-grown crystal were systematically estimated on the basis of the Vickers hardness test for the first time. The transmission spectrum of Nd: GdNbO was measured in the wavelength range of 320-2400 nm at room temperature, and the absorption peaks were assigned. Results hold great significance for further research on Nd:GdNbO4. [ABSTRACT FROM AUTHOR]

A Nd-doped GdNbO crystal was grown successfully by Czochralski method. Its monoclinic structure was determined by X-ray diffraction; the unit-cell parameters are a = 5.38 Å, b = 11.09 Å, c = 5.11 Å, and β = 94.56°. The morphological defects of Nd:GdNbO crystal were investigated using the chemical etching with the phosphoric acid etchant. For a new crystal, the physical properties are of great importance. The hardness and density of Nd:GdNbO were investigated first. Thermal properties of Nd:GdNbO, including thermal expansion coefficient and specific heat, were measured along a-, b-, and c-crystalline axes. Thermal properties indicate that the Nd:GdNbO pumped along c-axis can reduce the thermal lensing effect effectively. The specific heat is 0.53 J g K at 300 K, indicating a relatively high damage threshold of Nd:GdNbO. The transmission and emission spectrum of Nd:GdNbO were measured, and the absorption peaks were assigned. The strongest emission peak of Nd:GdNbO is located at 1065.3 nm in the spectral range of 850-1420 nm excited by 808 nm laser. The refractive index of Nd:GdNbO was calculated with the transmission spectrum and fitted with Sellmeier equation. All these obtained results is of great significance for the further research of Nd:GdNbO. [ABSTRACT FROM AUTHOR]

Genotype 8 of yellow head virus (YHV-8) was identified recently, but the complete genome sequence of this new genotype has not been reported. In this study, the complete genome of YHV-8 isolate 20120706 collected from Hebei Province of China in 2012 was sequenced. It was found to be 26,769 nucleotides (nt) in length, including a 20,060-nt open reading frame 1 (ORF1), a 435-nt ORF2, and a 4971-nt ORF3. Isolate 20120706 shared 79.7-83.9% nucleotide sequence identity with all seven of the complete genome sequences of YHV that have been reported so far. The topology of a phylogenetic tree constructed based on the ORF1b region clearly showed that strain 20120706, together with five other YHV-8 strains isolated in China, represents a new genotype of YHV. This is the first report of the complete genome sequence of a YHV-8 isolate, and the 20120706 isolate will be useful for further analysis of the epidemiology and evolution of YHV-8. [ABSTRACT FROM AUTHOR]

A new piezoelectric single crystal LaGaFeSiO (LGFS) was grown by the Czochralski method firstly. Its structural parameters were obtained by Rietveld refinement to the X-ray diffraction. The effective segregation coefficient k of Fe in the LGFS was determined to be 0.6. The cost of LGFS is reduced due to the doping of cheap Fe. The crystal density was measured to be 5.7 g cm by the buoyancy method. The defect structure of LGFS crystal was investigated by the chemical etching with 85% HSO etchant. Dislocation etching pit patterns of LGFS crystal are consistent with the corresponding atomic arrangement schematics. Compared with LGS, LGN, LGT, and LGAS crystal, the LGFS crystal exhibits outstanding dielectric and piezoelectric properties, and ɛ , ɛ , d , and d are 20.86, 51.99, 6.5 pC/N, and −5.10 pC/N, respectively. Therefore, LGFS may be a new potential piezoelectric crystal with high performance and low expense. [ABSTRACT FROM AUTHOR]

A mixed laser crystal of Nd-doped GYNO crystal was grown successfully by Czochralski method. The crystal belongs to monoclinic system with space group I2/a, the structural parameters are obtained by the X-ray Rietveld refinement method. The defects and dislocations along three crystallographic orientations were studied by using the chemical etching method with the phosphoric acid etchant. The mechanical properties (including hardness, yield strength, fracture toughness, and brittle index) of the crystal were estimated by Vickers hardness test. The transmission spectrum was measured at room temperature, and the absorption peaks were assigned. Spectral properties of the as-grown crystal were investigated by Judd-Ofelt theory, and the Judd-Ofelt intense parameters Ω were obtained to be 9.674 × 10, 2.092 × 10, and 4.061 × 10 cm, respectively. [ABSTRACT FROM AUTHOR]

The performance of a laser-diode side-pumped Er:YSGG slab at a wavelength of 2.79 µm was investigated experimentally, and the laser output mode was analyzed using the theory of a thermally induced refractive index planar waveguide. Experimentally, a maximum continuous-wave output of 1.84 W with a slope efficiency of 11.2 %, and an optical-to-optical efficiency of 7.5 % at 2.79 µm was obtained with a 970-nm laser-diode dual-side-pumped Er:YSGG slab. To the best of our knowledge, the output power was the highest reported for a laser-diode-pumped Er:YSGG laser with a continuous-wave output at 2.79 µm. The numerical analysis showed that the output power was mainly limited by thermal effects in the thickness direction and the laser output transverse mode in the experiment was the fundamental mode in this direction. [ABSTRACT FROM AUTHOR]

A new laser medium Nd:GdTaO single crystal with high optical quality was grown successfully by the Czochralski method, and its high-efficiency laser operation at 1,066 nm was demonstrated for the first time. The absorption cross section of the crystal at 808 nm is 5.098 × 10 cm, and the full width at half maximum of this absorption band is about 6 nm. Spectral properties are investigated by Judd-Ofelt theory. The stimulated emission cross section at 1,066 nm is 3.9 × 10 cm, and the fluorescence lifetime of F level is 178.4 μs. A diode end-pumped Nd:GdTaO laser at 1,066 nm with the maximum output power of 2.5 W is achieved in the continuous-wave mode. The optical-to-optical conversion efficiency and slope efficiency are 34.6 and 36 %, respectively. In addition, the fluorescence branching ratio of F → I transition reaches 44.4 %, indicating that Nd:GdTaO may be an efficient laser medium at 920 nm. All the results demonstrate that Nd:GdTaO crystal is a good candidate for laser diode-pumped laser material. [ABSTRACT FROM AUTHOR]

Bacillus thuringiensis ( Bt) is the most widely used insecticidal microbe due to its specific toxicity and safe use with respect to animals and the environment. In this study, we isolated Bt strain Q52-7 from a soil sample collected in the Qian Shan District, Liao Ning Province, China. We observed that the Q52-7 strain produced spherical crystals. The Bt Q52-7 strain had high toxicity against Asian Cockchafer (Holotrichia parallela), exhibiting an LC of 3.80 × 10 cfu/g, but is not toxic for Anomala corpulenta Motschulsky and Holotrichia oblita. Using general cry8 primers, we amplified a 1.3 kb fragment with the polymerase chain reaction. Specific primers were designed for the amplified fragment to clone the full-length coding region. A novel gene, cry8Na1, had 69 % sequence similarity with cry8Ca1. cry8Na1 gene was successfully expressed in the HD-73 acrystalliferous mutant of Bt subsp . Kurstaki HD-73. Bioassays demonstrated that the Cry8Na1 protein is highly toxic for the H. parallela, with a 50 % lethal concentration of 8.18 × 10 colony forming units per gram. [ABSTRACT FROM AUTHOR]

DNA methylation is one of the most important epigenetic modifications involved in the development and differentiation in plants. Hypocotyl and cotyledon are the two major tissues of cauliflower ( Brassica oleracea L. var. botrytis) seedlings. Both tissues show significantly different tissue specificity and regenerative abilities in vitro. However, the characteristics of DNA methylation modification and its roles in regulating the organ development in cauliflower remain largely unknown. In the present study, the DNA methylation status between the hypocotyl and cotyledon of cauliflower seedlings were analyzed. The results indicated that although the hypocotyl and cotyledon of cauliflower seedlings share the same genome, the genomic DNA methylation levels and patterns at CCGG sites were different. Compared with the cotyledon, the hypocotyl showed higher DNA methylation level, and more loci showing methylation pattern adjustments were also discovered. Twelve loci with changes of DNA methylation patterns were further explored. The quantitative expression analysis indicated that eight out of twelve sequenced fragments showed differential expression between the hypocotyl and cotyledon, of which the expression of six sequences was identified to be negative correlation with their DNA methylation status. In addition, three main DNA methyltransferase genes MET1, CMT3 and DRM were first explored in cauliflower. The results indicated that the expression of these three genes was closely associated with the different DNA methylation status in the hypocotyl and cotyledon. These findings provided more information to further explore the roles of DNA methylation modification in tissue differentiation and development of cauliflower. [ABSTRACT FROM AUTHOR]

Edwardsiella tarda has become one of the most important emerging pathogens in aquaculture industry. Therefore, a rapid, reproducible, and sensitive method for detection and quantification of this pathogen is needed urgently. To achieve this purpose, we developed a TaqMan-based real-time PCR assay for detection and quantification of E. tarda. The assay targets the hemolysin activator HlyB domain protein of E. tarda. Our optimized TaqMan assay is capable of detecting as little as 40 fg of genomic DNA per reaction. A standard curve was generated from the threshold cycle values ( y) against log ( E. tarda genomic DNA concentration) as x. The intra- and inter-assay coefficient of variation (CV) values were less than 2.06% and 1.05% respectively, indicating that the assay had good reproducibility. This method is highly specific to E. tarda strains, as it shows no cross-reactivity to Edwardsiella ictaluri, a member of the same genus, or to nine other fish-pathogenic bacteria species belonging to three other genera. This sensitive and specific real-time PCR assay provides a valuable tool for diagnostic quantitation of E. tarda in clinical samples. [ABSTRACT FROM AUTHOR]

High gravity (HG) or very high gravity (VHG) brewing has become popular in modern breweries due to its economic and product quality advantages. However, there are the negative impacts such as the fermentation performance of brewer's yeast in HG or VHG wort, which are closely related to changes in cell physiological activity. In the present study, 3 kinds of worts, with different gravities, were used to examine the systematic effects on fermentation performance and physiological activity of lager yeast FBY009505 ( Saccharomyces pastorianus) and ale yeast FBY0099 ( Saccharomyces cerevisiae), as well as the resulting beer flavor. Results showed that the responses of FBY009505 and FBY0099 to the HG or VHG worts were similar. The specific fermentation rate and viability of cropped yeast of FBY009505 and FBY0099 were decreased with increasing wort gravity. The increased wort gravity resulted in the increase of energy charge and the decrease of α-glucosides transport rate and glycolytic enzyme activities. Moreover, the environmental stresses in the HG or VHG wort showed a higher inhibitory activity against α-glucoside transport than glycolytic enzymes. The content of intracellular trehalose and glycerol of FBY009505 and FBY0099 increased with the increase in wort gravity. The results from this study provided a potential means to systematically understand the physiology of brewer's yeast under HG or VHG conditions. [ABSTRACT FROM AUTHOR]

Edwardsiella tarda is a major pathogen in aquatic environments that can cause heavy economic losses. An improved method for quick and accurate detection of E. tarda by loop-mediated isothermal amplification (LAMP) with two additional loop primers was developed by targeting the EsrB gene ( EsrB - LAMP). In this method, the Mg concentration, reaction temperature, and reaction time were optimized to 8 mmol/L, 61°C, and 40 min, respectively. The detection limit with the EsrB gene was as low as 10 copies, which is 100 times more sensitive than that of conventional polymerase chain reaction (PCR). The EsrB-LAMP assay was shown more sensitive and rapid than previously reported LAMP assays targeting the hemolysin gene ( hemolysin -LAMP) for detection of E. tarda. The EsrB -LAMP was also highly specific to E. tarda and had no cross-reaction with 13 other strains of bacteria. The assay can be carried out in a simple heating device and the EsrB-LAMP products can be visually detected by adding fluorescent dye to the reaction mixture. Taken together, the improved EsrB-LAMP diagnostic protocol has the potential for detection of E. tarda from indoor and outdoor samples. [ABSTRACT FROM AUTHOR]

Edwardsiella tarda is one of the most important emerging pathogens in the global aquaculture industries. As such, an accurate diagnosis and quantitative analytical methods are urgently needed for this bacterium. In this study, primers and a TaqMan probe specific to the conservative sequences of the 16S rRNA gene of E. tarda were designed. The concentration of primers and TaqMan probe were optimized to 200 nmol/L and 120 nmol/L, respectively. The detection sensitivity of the FQPCR assay was determined to be as low as five copies of the target sequence per reaction using the pGEM-16S rDNA recombinant plasmid as a template, which was 100 times more sensitive than conventional PCR. A standard curve by plotting the threshold cycle values ( y) against the common logarithmic copies (log10 n as x; n is copy number) of pGEM-16S rDNA was generated. The results of intra- and inter-assay variability tests demonstrate that the established FQ-PCR method was highly reproducible. The assay was specific for E. tarda as it showed that there was no cross-reactivity to eight additional bacterial pathogen strains in aquaculture. Thus, the FQ-PCR assay has the potential for diagnostic purposes and for other applications, especially for the rapid detection and quantification of low-grade E. tarda infections. [ABSTRACT FROM AUTHOR]

Saccharomyces pastorianus FBY0095 was mutated and variants were selected for efficient very high gravity brewing using 15% (w/v) maltose and 15% (w/v) ethanol. Two useful variants were obtained of which one (L6) had growth, wort consumption and ethanol production rates of 0.036, 1.13 and 0.49 g l h, respectively. The corresponding results for the wild type were 0.028, 0.98 and 0.4 g l h, respectively. The vitality of the variant (expressed as acidification power) was 2.5 while that of the wild type was 2.3. There was also an obvious improvement on flavor of resulting beer when using L6 and the other variant. [ABSTRACT FROM AUTHOR]

X-ray powder diffraction is an indispensable technique to study material structure, phase transition and so on. It is necessary for high quality diffraction data to get high-precision diffraction angle. This work proposed four corrected functions of X-ray powder diffraction angle. Two methods, linearization method and modified Levenberg-Marquardt iteration method, are given to solve the function parameters, and the modified Levenberg-Marquardt method has fast convergent speed and stable solution. Two methods can give closed parameters, including those of Lu, Liu, and Chu functions and polynomial. New-corrected functions were used to fit the diffraction angle error of the tetragonal rutile polycrystalline TiO2 mixed with Gd0.45Y2.55Sc2Ga3O12 as a standard sample, and the computation result indicates that these functions can characterize the diffraction error very well. In some cases, the new-corrected functions can describe the diffraction angle error better than the reported corrected functions. At the same time, the lattice parameter of Gd0.45Y2.55Sc2Ga3O12 was computed with two methods. When the corrected function parameters and lattice parameters were solved by the least square method, the interaction of the function parameters and lattice parameters would result in great error. However, when the X-ray diffraction angles were corrected by corrected functions using a standard sample, the authentic lattice parameters can be obtained by the least square fitting. [ABSTRACT FROM AUTHOR]

To study the thermal conduction characteristics of different doped YAG and GGG laser crystals, the thermal conductivity of different doped YAG and GGG laser crystals generated at 273–393 K were measured by making use of instantaneous measurement method. The temperature field model of the experimental sample was established and the function of thermal conductivity to temperature was educed. The obtained conductivity to temperature curves almost conformed to the experimental results. The experimental results show that the thermal conductivity of the laser crystal decline with temperature, the thermal conductivity of YAG laser crystal declines when adding Yb ions, and the thermal conductivity of the GGG laser crystal declines with the rising of the doped Nd ions concentration. Finally, the experimental results were theoretically explained. [ABSTRACT FROM AUTHOR]

Segregation during crystal growth from melt under two conditions is studied by using crystal mass, which can be measured easily, as an independent variable, and a method to determine the effective segregation coefficient and absorption cross section of optical dopant is given. When the segregated solute disperses into the whole or just a part of melt homogenously, the concentration C s in solid interface will change by different formulas. If the crystal growth interface is conical and segregated solute disperses into melt in total or part, the solute concentration at r = 2/3 R, where r is the distance from the growth cross section center and R the crystal radius, is independent on the shape of the crystal growth interface, and its variation at r = 2/3 R can be regarded as the result from crystal growth in flat interface. With C s variation formula in solid and absorption cross section σ for optical dopant, the absorption coefficients along the crystal growth direction can be calculated, and the corresponding experimental value can be obtained through the crystal optical absorption spectra. By minimizing the half sum, whose independent variables are k, Δ W or σ, of the difference square between the calculated and experimental absorption coefficients from one or more absorption peaks along the crystal growth direction, k and σ, or k and Δ W, can be determined at the same time through the Levenberg-Marquardt iteration method. Finally, the effective segregation coefficient k, Δ W and absorption cross sections of Nd:GGG were determined, the results fitted by two formula gave more closed effective segregation coefficient, and the value Δ W also indicates that the segregated dopant had nearly dispersed into the whole melt. Experimental results show that the method to determine effective segregation coefficient k, Δ W and absorption cross sections σ is convenient and reliable, and the two segregation formulas can describe the segregation during the crystal growth from melt relatively commendably. [ABSTRACT FROM AUTHOR]

The cytochrome cd1-containing nitrite reductase, nirS, plays an important role in biological denitrification. Consequently, investigating the presence and abundance of nirS is a commonly used approach to understand the distribution and potential activity of denitrifying bacteria, in addition to denitrifier communities. Herein, a rapid method for detecting nirS gene with loop-mediated isothermal amplification (LAMP) was developed, using Pseudomonas aeruginosa PAO1 (P. aeruginosa PAO1) as model microorganism to optimize the assay. The LAMP assay relied on a set of four primers that were designed to recognize six target sequence sites, resulting in high target specificity. The limit of detection for the LAMP assay under optimized conditions was 1.87 pg/reaction of genomic DNA, which was an order of magnitude lower than that required by conventional PCR assays. Moreover, it was validated that P. aeruginosa PAO1 cells as well as genomic DNA could be directly used as template. Only 1 h was needed from the addition of bacterial cells to the reaction to the verification of amplification success. The nirS gene of P. aeruginosa PAO1 in spiked seawater samples could be detected with both DNA-template based LAMP assay and cell-template based LAMP assay, demonstrating the practicality of in-field use. [ABSTRACT FROM AUTHOR]

Excessive or uncontrolled release of proinflammatory cytokines caused by severe viral infections often results in host tissue injury or even death. Phospholipase C (PLC)s degrade phosphatidylinositol-4, 5-bisphosphate (PI(4,5)P2) lipids and regulate multiple cellular events. Here, we report that PLCβ2 inhibits the virus-induced expression of pro-inflammatory cytokines by interacting with and inhibiting transforming growth factor-β-activated kinase 1 (TAK1) activation. Mechanistically, PI(4,5)P2 lipids directly interact with TAK1 at W241 and N245, and promote its activation. Impairing of PI(4,5)P2's binding affinity or mutation of PIP2-binding sites on TAK1 abolish its activation and the subsequent production of pro-inflammatory cytokines. Moreover, PLCβ2-deficient mice exhibit increased expression of proinflammatory cytokines and a higher frequency of death in response to virus infection, while the PLCβ2 activator, m-3M3FBS, protects mice from severe Coxsackie virus A 16 (CVA16) infection. Thus, our findings suggest that PLCβ2 negatively regulates virus-induced pro-inflammatory responses by inhibiting phosphoinositide-mediated activation of TAK1. Phospholipase C β (PLCβ) exhibits immuno-modulatory functions but its role in antiviral innate responses is unclear. Here, the authors provide evidence that PLCβ2 down regulates enterovirus-induced pro-inflammatory responses via inhibition of TAK1 activation, and suggest PLC as a potential therapeutic target. [ABSTRACT FROM AUTHOR]