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A Multi-Neutron Correlation Spectrometer (MuNCoS) composed of 80 detector modules was constructed at Peking University. A position resolution of less than 3 cm (FWHM) for a typical long scintillation module was obtained based on cosmic ray tests. A calibration method using an unstable nucleus beam of 11 Be, together with the fragment identification by using a zero degree telescope, has been successfully developed. Neutron detection efficiencies of 15(1)% and 17(2)% were achieved for neutron energy intervals of 30–40 MeV and 40–60 MeV, respectively, and at a signal charge threshold of 4 MeVee. The experimentally determined neutron detection efficiencies agree well with the simulation based on the GEANT4 code.

We carried out a nationwide survey to morphologically characterize and identify the geographic distribution of Ethiopian donkey populations. Here we re-evaluated some of the donkey populations previously identified and explored new ones from which we confirmed the existence of six distinct donkey populations and rejected one donkey population that was misidentified previously. We used twelve selected morphometric variables that recorded on a total of 569 adult donkeys (289 jacks and 280 jennets) spanning over wide arrays of ecologies in Ethiopia. Mean pairwise multiple comparisons (MPMC) between traits and multivariate analysis were carried out separately for jacks, jennets and aggregated gender. The MPMC showed significant differences between donkey populations for most of the traits studied. Principal component analysis showed that three body heights (height at wither, back and rump) and body length alone account for about 87.5% the total variations (eigenvalue = 10.49) of the 12 measured morphometric variables. Mahalanobis as well as Euclidean distances were also found to be highly significant ( P

Summary We determined the genetic diversity and evolutionary relationships among 26 Chinese indigenous horse breeds and two introduced horse breeds by genotyping these animals for 27 microsatellite loci. The 26 Chinese horse breeds come from 12 different provinces. Two introduced horse breeds were the Mongolia B Horse from Mongolia and the Thoroughbred Horse from the UK. A total of 330 alleles were detected, and the expected heterozygosity ranged from 0.719 (Elenchuns) to 0.780 (Dali). The mean number of alleles among the horse breeds ranged from 6.74 (Hequ) to 8.81 (Debao). Although there were abundant genetic variations found, the genetic differentiation was low between the Chinese horses, which displayed only 2.4% of the total genetic variance among the different breeds. However, genetic differentiation (pairwise FST) among Chinese horses, although moderate, was still apparent and varied from 0.001 for the Guizou–Luoping pair to 0.064 for the Jingjiang–Elenchuns pair. The genetic differentiation patterns and genetic relationships among Chinese horse breeds were also consistent with their geographical distribution. The Thoroughbred and Mongolia B breeds could be discerned as two distinct breeds, but the Mongolia B horse in particular suffered genetic admixture with Chinese horses. The Chinese breeds could be divided into five major groups, i.e. the south or along the Yangtze river group (Bose, Debao, Wenshan, Lichuan, Jianchang, Guizhou, Luoping, Jinjiang and Dali), the Qinghai-Tibet Plateau group (Chaidamu, Hequ, Datong, Yushu, Tibet Grassland and Tibet Valley), the Northeast of China group (Elenchuns, Jilin and Heihe), the Northwest of China group (Kazakh, Yili and Yanqi) and the Inner Mongolia group (Mongolia A, Sanhe, Xinihe,Wuzhumuqin and Sengeng). This grouping pattern was further supported by principal component analysis and structure analysis.

A sample of 129 unresolved radio sources with ultrahigh linear polarization (>30 per cent) has been selected from the NRAO VLA Sky Survey. Such high average linear polarization is unusual in extragalactic sources. Higher resolution Australia Telescope Compact Array and Very Large Array observations confirm the high average polarization but find that most of these sources are extended. The Sloan Digital Sky Survey spectroscopy, where available, shows that the optical counterparts are elliptical galaxies with no detectable emission lines. The optical spectra, radio luminosity, linear size and spectral index of these sources are typical of radio-loud active galactic nuclei. Galaxy counts within a 1 Mpc radius of the radio sources show that these highly polarized sources are in environments similar to their low polarization (

The structural and electronic properties of the gold in situ impurity ( Au Hg ) and gold interstitial defect ( Au i ) in Hg 0.75 Cd 0.25 Te (MCT) have been studied by plane-wave pseudopotential methods based on the density functional theory. Valence charge density, electron localization function (ELF), density of states and formation energy of gold impurity and defect were calculated to reveal the dopant stability and doping efficiency. The results indicate that the in situ gold impurity maintains a relative strong bonding with the host atom. The impurity Au Hg creates a shallow acceptor level that is 23 meV above VBM. However, the interstitial gold defect is dominant donor. Under Hg-rich molecular beam epitaxy (MBE) growth condition, due to the self-compensating effect between Au Hg and Au i , the Fermi level is pinned close to CBM by which the gold impurity cannot behave as an efficient acceptor. Whereas under Te-rich MBE growth condition and liquid phase epitaxy (LPE) growth condition, the self-compensating effect is overcame and the in situ gold impurity acts as an efficient p-type dopant.

Wool is produced via synthetic processes of wool follicles, which are embedded in the skin of sheep. The development of new-generation sequencing and RNA sequencing provides new approaches that may elucidate the molecular regulation mechanism of wool follicle development and facilitate enhanced selection for wool traits through gene-assisted selection or targeted gene manipulation. We performed de novo transcriptome sequencing of skin using the Illumina Hiseq 2000 sequencing system in sheep (Ovis aries). Transcriptome de novo assembly was carried out via short-read assembly programs, including SOAPdenovo and ESTScan. The protein function, clusters of orthologous group function, gene ontology function, metabolic pathway analysis, and protein coding region prediction of unigenes were annotated by BLASTx, BLAST2GO, and ESTScan. More than 26,266,670 clean reads were collected and assembled into 79,741 unigene sequences, with a final assembly length of 35,447,962 nucleotides. A total of 22,164 unigenes were annotated, accounting for 36.27% of the total number of unigenes, which were divided into 25 classes belonging to 218 signaling pathways. Among them, there were 17 signal paths related to hair follicle development. Based on mass sequencing data of sheepskin obtained by RNA-Seq, many unigenes were identified and annotated, which provides an excellent platform for future sheep genetic and functional genomic research. The data could be used for improving wool quality and as a model for human hair follicle development or disease prevention.

Tibetan sheep, an indigenous breed, have a wide variety of phenotypes and a colorful coat, which make this breed an interesting model for evaluating the effects of coat-color gene mutations on this phenotypic trait. The agouti signaling protein (ASIP) gene is a positional candidate gene, as was inferred based on previous study. In our research, ASIP gene copy numbers in genomic DNA were detected using a novel approach, and the exon 2 g.100-104 mutation and copy number variation (CNV) of ASIP were associated with coat color in 256 sheep collected from eight populations with different coat colors by high-resolution melting curve assay. We found that the relative copy numbers of ASIP ranged from one to eight in Tibetan sheep. All of the g.100-104 genotypes in the populations were in Hardy-Weinberg equilibrium, and there was no relationship between the g.100-104 genotype and coat color (P > 0.05). The single ASIP CNV allele was found to be almost entirely associated with solid-black coat color; however, not all solid-black sheep displayed the putative single ASIP CNV genotype. From our study, we speculate that the ASIP CNV is under great selective pressure and the single ASIP CNV allows selection for black coat color in Tibetan sheep, but this does not explain all black phenotypes in Tibetan sheep.

The relationship between the emission-line equivalent width and the continuum luminosity, so called the Baldwin effect, plays an important role in studying the physics of the broad line region of AGNs. Using the archived ultraviolet spectra obtained by IUE, HST, and HUT in 1978-2002, we investigated the intrinsic CIV Baldwin effect of a well-studied Seyfert 1 galaxy NGC 4151. Both its continuum flux and CIV emission-line flux varied about two orders of magnitude in more than two decades, making it one of the best targets for studying the slope variation of the Baldwin effect. We fitted the CIV line profile of the 490 archived UV spectra of NGC 4151 with the same model consisting of a few Gaussian components, and derived the slope in the log-log plot for the total flux of CIV emission line against the UV continuum flux in different observation epochs.We found that the slope is not constant for NGC 4151, as it varies from 0.58 in the highest flux epoch to 0.83 in the lowest flux epoch. The slope evidently decreases as the continuum flux increases, which reinforces the previous findings of the non-constant slope in the H_beta Baldwin effect of NGC 5548 and the CIV Baldwin effect of Fairall 9. Our result suggests that such a non-constant slope may not be unusual for AGNs. Its physical origin is probably related to the different non-linear responses of the emission line to the variable ionizing continuum caused by the different accretion modes at different luminosity levels. We briefly discuss the effects of various absorption components in the CIV line profile of NGC 4151 and argue that the slope variation is not driven mainly by the absorption effect. Intensive, long-term and high resolution spectral observations of strongly variable AGNs are needed in the future to confirm our result., Comment: 8 pages, 5 figures, references added and typo corrected, accepted for publication in A&A

The desmoglein 4 (DSG4) gene is a potential candidate in the search for genes that may affect wool traits, because of its function. This study aimed to screen for polymorphisms in partial exon 16 and 3ꞌUTR of the sheep desmoglein 4 DSG4 gene, and to test its possible association with wool length and crimp associated with fur. Overall, 326 sheep were scanned via single-strand conformational polymorphism assay, through three pairs of primers. The breeds included Tan, Han, and TanxHan from China, Polled Dorset from Australia, and Suffolk from Britain genotypes AA, BB, and AB for primer2 and genotypes DD, EE, and DE for primer3 were detected in native breeds. Six SNPs and 3-bp insertion/deletions were found in exon 16, of which 4 lead to amino acid substitutions. In addition, 1 SNP was found in 3ꞌUTR. The DSG4 genotype was found to be strongly associated with all wool traits that were considered in this study (P0.01). Sheep with the genotype MM had a higher least square mean compared to sheep with the genotype WW or WM with respect to birth scapular wool length (P0.01), crimp number of birth scapular wool crimp (P0.01), crimp number of weaning scapular wool crimp (P0.01), and crimp number of weaning rump wool crimp (P0.01, P0.05). In conclusion, our study is the first to demonstrate that the DSG4 gene may be a candidate, or major gene, which influences important wool traits.

Monitoring mouse behavior is a critical step in the development of modern pharmacotherapies.Here we describe the application of a novel method that utilizes a touch display computer (tablet) and software to detect, record, and report fine motor behaviors. A consumer-grade tablet device is placed in the bottom of a specially made acrylic cage allowing the animal to walk on the device (MouseTrapp). We describe its application in open field (for general locomotor studies) which measures step lengths and velocity. The device can perform light-dark (anxiety) tests by illuminating half of the screen and keeping the other half darkened. A divider is built into the lid of the device allowing the animal free access to either side.Treating mice with amphetamine and the delta opioid peptide receptor agonist SNC80 stimulated locomotor activity on the device. Amphetamine increased step velocity but not step length during its peak effect (40-70min after treatment), thus indicating detection of subtle amphetamine-induced effects. Animals showed a preference (74% of time spent) for the darkened half compared to the illuminated side.Animals were videotaped within the chamber to compare quadrant crosses to detect motion on the device. The slope, duration and magnitude of quadrant crosses tightly correlated with overall locomotor activity as detected by MouseTrapp.We suggest that modern touch display devices such as MouseTrapp will be an important step toward automation of behavioral analyses for characterizing phenotypes and drug effects.

Polyurethanes (PU) based on poly(butylene adipate) [PU(PBA)] and poly(oxypropylene) [PU(PPG)] polyols are employed as a graft agent to prepare interpenetrating polymer networks of urethane-modified bismaleimide (UBMI) and the diglycidyl ether of bisphenol A (Ep) (UBMI/Ep graft-IPNs). The UBMI is introduced and partially grafted to the epoxy by PU graft agents, and then simultaneous bulk polymerization technique is used to prepare the graft-IPNs. All the PU graft agents were characterized by infrared (IR). The tensile strength of both the UBMI/Ep graft-IPNs with PU(PBA) and PU(PPG) graft agent systems increased to a maximum value with increasing UBMI content in the system and then decreased with further increasing the UBMI content. For both kinds of PU with various molecular weight in the UBMI/Ep graft-IPNs, the Izod impact strength increased with the UBMI contents increasing. The better compatibility of PU(PBA)-based UBMI/Ep graft-IPNs led to higher impact strength. On the contrary, the fracture energy (GIC value) of the resultant UBMI/Ep graft-IPN showed that the UBMI/Ep graft-IPN with PU(PPG) graft agent had much higher GIC value than that with PU(PBA) graft agent. The morphology of this IPN with PU(PBA) graft agent exhibited a homogeneous one-phase system, while the UBMI/Ep graft-IPN with PU(PPG) graft agent showed a two-phase morphology with the UBMI particles dispersed in the epoxy matrix.

The large scale magnetic fields of our Galaxy have been mostly revealed by rotation measures (RMs) of pulsars and extragalactic radio sources. In the disk of our Galaxy, the average field strength over a few kpc scale is about 1.8 μG, while the total field, including the random fields on smaller scales, has a strength of about 5 μG. The local regular field, if it is part of the large scale field of a bisymmetric form, has a pitch angle of about −8°. There are at least three, and perhaps five, field reversals from the Norma arm to the outer skirt of our Galaxy.

Furfuryl alcohol (FA) prepolymer was developed to fabricate pultruded fibre-reinforced FA resin composites. FA monomer with p -toluene sulfonic acid was used to synthesize the FA prepolymer, which provided a good balance between processing parameters (including pot life, reactivity and wetting ability) and properties of the composites. The reactions occurring during synthesis of the FA prepolymers and the post-curing treatment were investigated by 1 H n.m.r. and i.r. spectroscopies. It was found that the mechanical properties of the composites increase with increasing die temperature or decreasing pulling rate. From the study on the mechanical properties of the composites, it was found that an optimum post-cure time exists when the post-cure temperature is above 200°C. It was also found that three kinds of reaction - crosslinking, chain extension polymerization and the transformation of the methylene ether linkage to a methylene linkage -occur during the post-curing treatment.

A novel process has been developed to manufacture pultruded fibre-reinforced furfuryl alcohol (FA) resin composites. In this paper, the effects of fibre reinforcement type and content on the static, dynamic mechanical and thermal properties of the FA resin pultruded composites are investigated. The mechanical properties increase with increasing volume content of the glass or carbon fibres, with the glass fibre-reinforced furfuryl alcohol (GF/FA) composite exhibiting maximum mechanical property values at a filler content of 5 phr. High catalyst content and die temperatures are necessary for manufacturing FA pultruded composites with high filler content. GF/FA pultruded composites retain their mechanical properties at elevated temperatures better than do unsaturated polyester pultruded composites. Dynamic mechanical analysis revealed that the dynamic storage modulus of the GF/FA pultruded composites increases with increasing post-cure time. Tan δ of GF/FA decreases and its glass transition temperature increases with decreasing pulling rate or increasing post-cure time. The glass and carbon fibre-reinforced FA pultruded composites possess high heat distortion temperature and good flexural properties, in comparison with other pultruded composites.

A method is proposed to modify Prolog compilers so that infinite looping can often be avoided in recursive Prolog programs. The study is carried out in the context of deductive databases. Termination of recursive query processing here is related to boundedness: uniform boundedness and extensional boundedness. Limitations of this method are briefly discussed. >

A contrastive research on two-proton (2p) emissions from excited states of the even-Z nucleus 28S and its one-proton daughter, the odd-Z nucleus 27P was performed by complete-kinematics measurements. The opening angles as well as relative momenta between two emitted protons and invariant masses of decaying systems were reconstructed through the event-by-event analysis of heavy fragments coincident with two protons. With the help of Monte Carlo simulations, results show a diproton-type decay with the branching ratio of 20 − 7 + 6 % for 28S while mainly three-body simultaneous decay in the phase space and/or 2p sequential emission for 27P. Present results show that the diproton correlations may result from the proton configuration in the initial state like 2p skin/halo structure rather than the deformed orbit.