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Neutron stars are observed to undergo small, abrupt rotational speed-up. This phenomenon is known as glitch. In pulsar timing observations, detection of a neutron star glitch is constrained by the time of occurrence of the event relative to entire observing span and observing cadences, time of occurrence of preceding/subsequent glitches relative to observing cadences and the strength of timing noise. Using the Yu et al. data sets, in this paper, we analyse the observational selection in terms of detection probability. We define partial probabilities for the constraints and use the Monte Carlo method with assuming glitches distribute uniformly to solve the complete probability formula for both group case involving 157 pulsars and individual cases for each of the seven pulsars with glitch numbers ≥5. In the simulations, numerical Bayesian inference is used for glitch identification. With the derived detection probability density and observed results, we uncover glitch size probability distribution embedded in the data for both the group and individual cases. We find the most prominent correction occurred for PSR J1341–6220, in which the exponent of the power-law model varies from the observed +0.7+1.4-0.7 to -0.4+1.0-0.4. We suggest observers determine the detection probability for glitch theories, e.g. the self-organized criticality. [ABSTRACT FROM AUTHOR]

Soil erodibility has confounded researchers for decades. Difficulties arise with initiation of motion, pore-water status, physical and perhaps biological, material properties and type of applied energy (i.e., rainfall, runoff, freezing or thawing, wind). Though specific tests have been developed to determine critical shear stress and soil erodibility, solutions do not seem to conform to theory. We have models for erosion assessment and although each provides practical information for planning and management, all share a need to improve predictions for soil detachment. Here, a series of submerged jet tests (JET) are performed on samples of three soils prepared to represent agricultural conditions (i.e., modest bulk density), five initial soil water contents are imposed during sample packing that affected soil void ratio and four water potential gradients are imposed during jet testing. Results, for both coarseand fine-grained soils, indicate that critical shear stress can be predicted with knowledge of the silt content, void ratio and water potential gradient and soil erodibility can be predicted with knowledge of critical shear stress, clay content and void ratio. This study was limited by the number of soils examined; however, the results are thought provoking. [ABSTRACT FROM AUTHOR]

The authors present a study on the hot formability of 7020 aluminium alloy. Isothermal hot compression tests of solid cylindrical specimens were performed in the temperature range of 300-550°C and the strain rate range of 0·001-10 s-1. Stress-strain curves obtained from the experiment data are fitted using the Sellars-Tegart constitutive equation to obtain the constitutive parameters. Using the dynamic material model, the authors develop a processing map based on the flow stress data. The map shows that the parameters suitable for hot working are a temperature range of 450-550°C and a strain rate range of 0·001-0·1 s-1. This parameter range is where the efficiency of power dissipation is above 27% and where dynamic recrystallisation occurs. Unstable regions to be avoided in hot forming are deduced from an instability condition. The processing map is validated by comparing the microstructures of deformed compression specimens. [ABSTRACT FROM AUTHOR]

TIM-1, a member of T-cell immunoglobulin domain and mucin domain (TIM) gene family, was implicated as an asthma susceptibility gene in previous studies. TIM-1 was expressed on CD4+ T cells after activation and its expression was sustained preferentially in T-helper type 2 (TH2) but not in TH1 cells, therefore TIM-1 became a good candidate gene for atopic diseases. Recent studies indicated that two insertion/deletion (ins/del) coding genetic polymorphisms in exon 4 of TIM-1 were associated with asthma susceptibility in some but not in all populations. In order to investigate the relationship between TIM-1 genetic polymorphisms and asthma in Chinese Han population, we performed a case-control study for two insertion/deletion polymorphisms in TIM-1 exon 4 (5383_5397ins/del and 5509_5511delCAA) and a single nucleotide polymorphism (SNP) in intron 8 (IVS 8+9 G/A) between a healthy control group of 309 people and an asthma patient group of 352 people recruited from Chinese Han population. The polymorphisms were genotyped and the allele and genotype frequencies were analysed, but none of the three polymorphisms showed association with asthma susceptibility in single-locus association analyses. Linkage disequilibrium (LD) analyses demonstrated that the two insertion/deletion polymorphisms were in strong LD but the haplotypes constructed from these two polymorphisms showed no significant association with asthma. In conclusion, our findings suggest that 5383_5397ins/del, 5509_5511delCAA and SNP IVS 8+9 G/A polymorphisms are not associated with asthma susceptibility in Chinese Han population. [ABSTRACT FROM AUTHOR]

Asthma is a complex polygenic disease with gene–environment interactions being important. It has been previously suggested that ADAM33, which is a member of a gene family that encodes membrane-anchored proteins with a disintegrin and a metalloprotease domain, is primarily expressed in lung fibroblasts and bronchial smooth muscle cells and has been associated with airway remodelling and bronchial hyperresponsiveness. A significant association has previously been demonstrated between single nucleotide polymorphisms (SNPs) and haplotypes of the ADAM33 and asthma in ethnically diverse populations. To assess whether SNPs or haplotypes of ADAM33 are related to asthma in a Chinese Han population, we genotyped three SNPs of ADAM33 (7575G/A in intron 6, 11188A/T in intron 19, and 12433T/C in exon 20) in a case-control study involving 296 patients with asthma and 270 healthy controls. No significant association was detected between these three SNPs and asthma susceptibility in the Chinese population. [ABSTRACT FROM AUTHOR]

The Changbai Mountain Natural Reserve (2000 km[sup 2]), north-east China, is a very important ecosystem representing the temperate biosphere. The cover types were derived by using multitemporal Landsat TM imagery, which was modified with DEM data on the relationship between vegetation distribution and elevation. It was classified into 20 groups by supervised classification. By comparing the results of the classification of different band combinations, bands 4 and 5 of an image from 18 July 1997 and band 3 of an image from 22 October 1997 were used to make a false colour image for the final output, a vegetation map, which showed the best in terms of classification accuracy. The overall accuracy by individual images was less than 70%, while that of the multitemporal classification was higher than 80%. Further, on the basis of the relationship of vegetation distribution and elevation, the accuracy of multitemporal classification was raised from 85.8 to 89.5% by using DEM. Bands 4 and 5 showed a high ability for discriminating cover types. Images acquired in late spring and mid-summer were recognized better than other seasons for cover type identification. NDVI and band ratio of B4/B3 proved useful for cover type discrimination, but were not superior to the original spectral bands. Other band ratios like B5/B4 and B7/B5 were less important for improving classification accuracy. The changes of spectral reflectance and NDVI with season were also analysed with 10 images ranging from 1984 to 1997. Seperability of images in terms of classification accuracy was high in late spring and summer, and decreased towards winter. There were five vegetation zones on the mountain, from the base to the peak: deciduous forest zone, mixed forest zone, conifer forest zone, birch forest zone and tundra zone. Spruce-fir conifer dominated forest was the most dominant vegetation (33%), followed by mixed forest (26%), Korean pine forest (8%) and mountain birch forest (5%). [ABSTRACT FROM AUTHOR]

A rigorous technique of monitoring the vertical column density (VCD) of NO2 by using the scattered solar radiation is reported. By analyzing the optical path, the method of collecting the useful scattered solar radiation is achieved. By using this method, the collecting equipment and procedure of solar radiation could be greatly simplified. And through the actual measurement, it is proved that the VCD of NO2 measured by using the scattered solar radiation is very close to that from the direct solar radiation. [ABSTRACT FROM AUTHOR]

The FeSexTe1-x has been proved to be a novel superconductivity with topological properties. Iron chalcogenide FeSexTe1-x attracted much attention because of its simple structure, which is favorable for probing the superconducting mechanism. The superconducting properties are significantly affected by different microstructures. In this work, FeSe0.5Te0.5 crystals with different structures including morphology, crystal structure, electronic structure, phonon mode, chemical states of the elements caused by different grinding techniques were grown. The structure related magnetism, transport properties, band structure, critical temperature, and critical current were studied. The Fe atoms contribute to the density of state around the Fermi level. The highest superconducting shielding volume fraction as well as the maximum critical current value existed in the sample having the minimum lattice parameter and highest Te element content deficiency. [ABSTRACT FROM AUTHOR]

This article reports on the study of microstructure and dislocation of InN films using high resolution x-ray diffraction grown on sapphire (0001) both by metalorganic chemical vapor deposition (MOCVD) and molecular beam epitaxy (MBE). The mosaic tilt, twist, and correlation lengths of InN films are determined by using symmetrical and asymmetrical reflections as well as reciprocal space mapping. Deducing from these results, MBE-grown InN film exhibits the edge-type dislocations of 4.0×109 cm-2, which is about ten times higher than the density of screw-type dislocations. In MOCVD-grown InN sample, the edge-type dislocations density is as high as 2.1×1010 cm-2, and the screw-type dislocations density is 1.3×109 cm-2. They indicate that edge type is the predominant dislocation type in the InN films. By comparing the reported transmission electron microscopy results, the accuracy of evaluation for the dislocation density using the mosaic model is proved. [ABSTRACT FROM AUTHOR]

A systematic set of flume tests was developed to explore the relation between soil water content and soil detachment capacity for a coarse-grained soil and a fine-grained soil. The experiments included aging treatments (three volumetric water contents of 4.0, 11.5, and 21.7% for the sandy loam soil and 5.0, 10.5, and 17.4% for the silt loam soil, and seven aging durations of 0, 12, 24, 36, 48, 60, and 72 h) and drying treatments (saturated soil samples oven-dried for 0, 12, 24, 36, 48, 60, and 72 h). Results showed that soil detachment capacity for these two soils presented unique patterns as soil water content increased: the fine-grained soil presented an increasing and then a decreasing trend under aging treatments, whereas the coarse-grained soil showed a continuous increasing trend as soil water content increased. Both patterns could be fitted by quadratic equations. The effect of soil water content on soil detachment capacity was mainly reflected by water-stable aggregate content. Higher soil water content results in weaker bonds for fine-grained soil but in less slaking for coarse-grained soil. Lower soil water content leads to less slaking for fine-grained soil but more particle deposition and cementation for coarse-grained soil. Future work will include additional soil textures and focus on soil erodibility and critical shear stress to expand our understanding of soil detachment influenced by soil water content. [ABSTRACT FROM AUTHOR]

The four R-spondins (RSPO1-4) and their three related receptors LGR4, 5 and 6 (LGR4-6) have emerged as a major ligand-receptor system with critical roles in development and stem cell survival through modulation of Wnt signaling. Recurrent, gain-of-expression gene fusions of RSPO2 (to EIF3E) and RSPO3 (to PTPRK) occur in a subset of human colorectal cancer. However, the exact roles and mechanisms of the RSPO-LGR system in oncogenesis remain largely unknown. We found that RSPO3 is aberrantly expressed at high levels in approximately half of Keap1-mutated lung adenocarcinomas (ADs). This high RSPO3 expression is driven by a combination of demethylation of its own promoter region and deficiency in Keap1 instead of gene fusion as in colon cancer. Patients with RSPO3-high tumors (~9%, 36/412) displayed much poorer survival than the rest of the cohort (median survival of 28 vs 163 months, log-rank test P<0.0001). Knockdown (KD) of RSPO3, LGR4 or their signaling mediator IQGAP1 in lung cancer cell lines with Keap1 deficiency and high RSPO3-LGR4 expression led to reduction in cell proliferation and migration in vitro, and KD of LGR4 or IQGAP1 resulted in decrease in tumor growth and metastasis in vivo. These findings suggest that aberrant RSPO3-LGR4 signaling potentially acts as a driving mechanism in the aggressiveness of Keap1-deficient lung ADs. [ABSTRACT FROM AUTHOR]

The aim of this paper is to design an annular photoelectric sensor measurement system for determination of fat content in milk. The system is composed of annular photoelectric sensor, lifting stage, thermoelectric cooler (TEC), two-stage amplifier module, an analogue-to-digital (A/D) converter, microprocessor, data storage module, data display module and key module. Based on Mie light scattering theory, the absorbance is adopted as the optical parameter representing the milk fat content. Homogenizalion is realized by TEC to ensure that the scattering coefficient keeps constant. Through modelling and prediction, we can choose the best measurement temperature. Results of this study indicate the feasibility and real-time performance of using this measurement system for milk fat analysis. [ABSTRACT FROM AUTHOR]

A remote monitoring system for optical fibre smart structure based on advanced reduced instruction set computing (RISC) machines (ARM) and general packet radio service (GPRS) is presented. The system consists of laser light source, fibre optic intelligent structures, the monitoring host computer and monitoring centre. Monitoring host is made up of advanced reduced instruction set computing (RISC) machines (ARM) and general packet radio service (GPRS) ARM microprocessor and wireless communication module. It is responsible for photoelectric signal acquisition. And the remote monitoring centre is responsible for signal receiving and processing. They communicate with each other through the wireless communication module which is controlled by the monitoring host. The monitoring experiments are carried out by loading on the composites structure. The composite is embedded with optical fibres which are distributed orthogonally forming a sensing network. The data that contain the health status information of the smart composites structure can be received and processed in monitoring centre and the damage position is located. The designed system decreases the negative effect of limitation factors such as the distance, region and time. The results show that the system' is stable and reliable. It provides a new method for condition monitoring of optical fibre smart structure. [ABSTRACT FROM AUTHOR]

Chalcone synthase (CHS, EC 2.3.1.74) is a key enzyme in the biosynthesis of flavonoids, which plays an important role in flower pigmentation and protection against UV, plant-microbe interactions, and plant fertility. In many plants, genes encoding CHS constitute a multigene family, wherein sequence and functional divergence occurred repeatedly. Since the genome of rice ( Oryza sativa) has been completely sequenced, many genes possessing typical CHS domains were assumed to be chs genes, although the sequence and functional divergence of this large gene family has not as yet been investigated. In this study, all putative CHS members from O. sativa were analyzed by the phylogenetic methods. Our results indicate that the members of rice CHS superfamily probably diverged into four branches. Members of each branch may perform specific functions. Two conserved chs genes clustered with chs genes from other monocotyledon and dicotyledon species are believed to encode true CHSs responsible for the biosynthesis of flavonoids and anthocyanins. Two chs genes in one distant branch might play some functions in fertility. Several other putative chs genes were clustered together, and the function of this branch could not be predicted. Many tentative chs genes were clustered together with fatty acid synthase (FAS) genes. These genes may belong to the fas gene family. [ABSTRACT FROM AUTHOR]

In this study, improved cross-search, bicubic spline interpolation and finite element (FE) methods are implemented into conventional digital image speckle correlation algorithm in order to reduce correlation computational time, to increase deformation measurement accuracy, and to smooth deformation distribution. With the improved correlation algorithms, an integrated computer-aided-measurement system, called micro-digital image speckle correlation (μ-DiSC) is built. This system is then applied to characterize the thermal property and fracture behavior of the plastic ball grid array (BGA) assembly and underfill thin film, and employed to validate the material constitutive relationship for a flip chip package and the fatigue life prediction model for a BGA assembly. The demonstration results are found to be in good agreement with those obtained from thermo-mechanical analyzer (TMA), finite element modeling (FEM), moiré interferometry (MI), and accelerated temperature cycling (ATC) test. Therefore, the system can be used as an effective experimental tool to characterize properties of electronic materials and verify findings of theoretical and numerical models for the establishment of reliability design methodology. [ABSTRACT FROM AUTHOR]

The m-plane GaN films grown on LiAlO2(100) by metal-organic chemical vapor deposition exhibit anisotropic crystallographic properties. The Williamson–Hall plots point out they are due to the different tilts and lateral correlation lengths of mosaic blocks parallel and perpendicular to GaN[0001] in the growth plane. The symmetric and asymmetric reciprocal space maps reveal the strain of m-plane GaN to be biaxial in-plane compress [variant_greek_epsilon]xx=-0.79% and [variant_greek_epsilon]zz=-0.14% with an out-of-plane dilatation [variant_greek_epsilon]yy=0.38%. This anisotropic strain further separates the energy levels of top valence band at Γ point. The energy splitting as 37 meV as well as in-plane polarization anisotropy for transitions are found by the polarized photoluminescence spectra at room temperature. [ABSTRACT FROM AUTHOR]

The nonpolar m-plane (1100) thin film GaN and InGaN/GaN light-emitting diodes (LEDs) grown by metal-organic chemical vapor deposition on LiAlO2 (100) substrates are reported. The LEDs emit green light with output power of 80 μW under a direct current of 20 mA for a 400×400 μm2 device. The current versus voltage (I-V) characteristic of the diode shows soft rectifying properties caused by defects and impurities in the p-n junction. The electroluminescence peak wavelength dependence on injection current, for currents in excess of 20 mA, saturates at 515–516 nm. This proves the absence of polarization fields in the active region present in c-plane structures. The light output intensity versus current (L-I) characteristic of the diode exhibits a superlinear relation at low injection current caused by nonradiative centers providing a shunt path and a linear light emission zone at high current level when these centers are saturated. [ABSTRACT FROM AUTHOR]

A correction to the article "Microstructure and dislocation of epitaxial INN films revealed by high resolution x-ray diffraction," published online on August 7, 2008, is presented.