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We develop an in-line distributed optical fiber acoustic sensor array based on Sagnac interferometer use it to measure and locate leaks for the fluid-filled (or gas-filled) pipelines in real time. The advantage of the sensor array is that it can monitor two or many pipelines at the same time. The traditional loop Sagnac interferometer is changed into in-line structure by a Faraday rotator mirror. The representation of phase change caused by leakage is formulated for optic signal; the measuring principle and the leaking source location method for the sensor array are analyzed. An experiment is designed to detect and locate leaks. The results verify that the system can realize leak detection and locate leak accurately, and the error is less than 0.54%. [ABSTRACT FROM AUTHOR]

The title cluster, [Ru(C7H11B10ClN2O6)(C2H3N)(C18H15P)] or [1,2-{3,5-(NO2)2(C6H3)COO}-1-(PPh3)-1-(CH3CN)-3-Cl-1-RuB10H8], has an iso- closo 11-vertex RuB10 core geometry with the metal occupying the unique six-connected apical position, giving the characteristic 11-vertex iso- closo [ MB10] metalloborane 1:2:4:2:2 stack. The ruthenium centre has three exo-polyhedral ligands: one triphenyl­phosphine, one aceto­nitrile and one 3,5-dinitro­benzoate, which is coordinated through Ru—O and B—O bonds, resulting in an exocyclic five-membered Ru/O/C/O/B ring. [ABSTRACT FROM AUTHOR]

Tuberculosis (TB) is one of the most common infectious diseases globally. The surfactant protein C (SFTPC), which is involved in innate immunity and surfactant function in the lung, may contribute toward the progression of TB. The aim of the present study was to preliminarily investigate the possible association of single nucleotide polymorphisms (SNPs) in the SFTPC gene with TB susceptibility and clinical phenotypes in a Western Chinese Han population. The improved multiplex ligation detection reaction method was used to genotype 6 SNPs in SFTPC, in 900 patients with TB and 1,534 healthy control subjects. It was found that the A allele for rs1124 and the C allele for rs8192313 were associated with increased susceptibility to TB, P=0.024 and P=0.045, respectively. However, these two P-values were not significant following Bonferroni correction. In all samples, the haplotype [CGA], representing three SFTPC variants, was revealed to increase the risk of TB (P=0.001 and P=0.005, following Bonferroni correction). Furthermore, patients with the AA genotype for rs1124 and with the CC genotype for rs8192313 were associated with higher levels of C-reactive protein (P=0.001 and P=0.005, respectively). The results of the present study indicated that the SFTPC SNPs may increase the susceptibility to TB and the immune response of the host to Mycobacterium tuberculosis and may potentially be novel biomarkers for the pathogenesis of TB. [ABSTRACT FROM AUTHOR]

The pristine and diethylenetriamine (DETA)-doped tungsten disulfide quantum dots (WS2 QDs) with an average lateral size of about 5 nm have been synthesized using pulsed laser ablation (PLA). Introduction of the synthesized WS2 QDs on the InGaAs/AlGaAs quantum wells (QWs) can improve the photoluminescence (PL) of the InGaAs/AlGaAs QW as high as 6 fold. On the basis of the time-resolved PL and Kelvin probe measurements, the PL enhancement is attributed to the carrier transfer from the pristine or DETA-doped WS2 QDs to the InGaAs/AlGaAs QW. A heterostructure band diagram is proposed for explaining the carrier transfer, which increases the hole densities in the QW and enhances its PL intensity. This study is expected to be beneficial for the development of the InGaAs-based optoelectronic devices. [ABSTRACT FROM AUTHOR]

Whether, how, and to what extent solutions of Bjorken-expanding systems become insensitive to aspects of their initial conditions is of importance for heavy-ion collisions. Here we study 1+1D and phenomenologically relevant boost-invariant 3+1D systems in which initial conditions approach a universal attractor. In Israel-Stewart theory (IS) and kinetic theory where the universal attractor extends to arbitrarily early times, we show that all initial conditions approach the attractor at early times by a power law while their approach is exponential at late times. In these theories, the physical mechanisms of hydrodynamization operational at late times do not drive the approach to the attractor at early times, and the early-time attractor is reached prior to hydrodynamization. In marked contrast, the attractor in strongly coupled systems is realized concurrent with hydrodynamization. This qualitative difference may offer a basis for discriminating weakly and strongly coupled scenarios of heavy-ion collisions. [ABSTRACT FROM AUTHOR]

As an important branch of non-destructive testing, electromagnetic ultrasonic testing is widely used in various industries because of its high detection efficiency and the lack of a need for the test sample to have a coupling agent or a surface pretreatment. As a core component of electromagnetic ultrasonic testing, electromagnetic acoustic transducers (EMATs) have received extensive attention in recent years. However, the mode selectivity of EMATs is reduced because of the non-uniformity of the magnetic field of traditional permanent magnets and the multimode phenomenon of guided waves. To solve this problem, an omni-directional magnetic-concentrator-type electromagnetic acoustic transducer (OD-MC-EMAT) is proposed herein. Which was added to the magnetic concentrator on a traditional EMAT to guide and concentrate the magnetic field of traditional permanent magnets, thereby improving the defect inspection ability of the EMAT. The proposed OD-MC-EMAT consisted of a cylindrical permanent magnet, an omni-directional magnetic concentrator, and a multi-cluster of circular meander coils, and it exhibited better mode selectivity than a traditional EMAT. A finite element simulation and an experiment proved that the mode selectivity of the transducer improved after adding the magnetic concentrator, and experiments to study the transducer characteristics and defect detection were also carried out. Finally, the configuration of the OD-MC-EMAT was optimized through an orthogonal experiment. The influence of each parameter on the transducing efficiency of the proposed OD-MC-EMAT was studied, and the optimal parameter combination was confirmed. • The proposed OD-MC-EMAT consisted of magnetic concentrator and traditional EMAT. • The amplitude of unwanted modes was reduced and mode selectivity was enhanced by OD-MC-EMAT. • OD-MC-EMAT has better frequency-response characteristics and sound-field is omni-direction. • The proposed OD-MC-EMAT is more suitable for defect inspection than traditional EMAT. • The effect of each parameter on transducing efficiency of proposed EMAT was studied and parameter combination was optimized. [ABSTRACT FROM AUTHOR]

Based on the systematic studies of the growth temperature, deposition rate, and annealing effects, the control of Co nanoparticle density, size, and alignment is demonstrated to be feasible on a nanostructured template Al2O3/NiAl(100). At 140–170 K, a slow deposition rate (0.027 ML/min) promises both the linear alignment and the high particle density. 1.5 ML Co nanoparticle assembly sustains the density of ∼260/104 nm2 even after 800–1090 K annealing. This study also indicates the possibilities of the controlled growth for nanoparticles of different materials. [ABSTRACT FROM AUTHOR]

The article focuses on the study of the relative thermodynamic stability of C-terminal peptidyl esters of O-hydroxy Thiophenol. Researchers have been studying methods for assembling polypeptides bearing complex oligosaccharide domains. Mechanistic basis in the previously described ligation strategy was determined through the unanticipated result that ligation progresses through quantitative O → S acyl transfer of the N-terminal coupling partner.

Self-consistent first-principles calculations with the generalized gradient approximation are employed to study the electronic structures, magnetic properties, effects of uniform strain and tetragonal distortion on RuMnCrZ(Z  =  P, As and Sb). It is found that they are all half-metallic ferrimagnets. Calculations show that the total magnetic moments of RuMnCrZ(Z  =  P, As and Sb) are in agreement with the Slater–Pauling 24 electron-rule. The effects of uniform strain and tetragonal distortion are studied for RuMnCrSb. For uniform strain, large spin-down band gaps are observed between  −4% and 0 and EF is located within the gap in the range of  −2% to 0. Furthermore, the total magnetic moment is 2 from  −4% to 0 uniform strain, and the spin polarization P of 100% is observed in the range of  −2% to 0, which indicates that the perfect half-metallicity of RuMnCrSb is maintained within the range. For tetragonal distortion, the spin-down band gaps exist for a large range of distortion:  −8% distortion 6% and the Fermi level is always within the gap for this range. 100% P and the total magnetic moment of 2 are maintained within the range of  −6% to  +5%. It is concluded that the perfect half-metallicity of RuMnCrSb appears in the range of  −6% to  +5% tetragonal distortion. The half-metallicity is more stable in the case of tetragonal distortion. [ABSTRACT FROM AUTHOR]

Many beam related instabilities have been observed in EAST. This paper reports on detailed calculations of beam driven fishbone and sawtooth instabilities using a general fishbone dispersion relation. The ideal fluid contribution and eigenfunction were calculated with the magnetohydrodynamic code NOVA, the kinetic contribution was evaluated with sample fast ion distributions in the guiding center code ORBIT, and the general inertial term was calculated using experimental data. The sawtooth branch was stabilized both by co-beam injection and balanced injection, but the stable domain for the sawtooth and fishbone modes is wider for balanced injection. The fishbone of the precessional branch is excited by both trapped and passing particles. To widen the stable domain, we propose a modulated balanced beam heating scenario for long pulse, high beta discharges in EAST, with the single beam pulse turn on time shorter than the plasma energy confinement time and longer than the beam ion slowing down time. [ABSTRACT FROM AUTHOR]

By using the designed photonic crystal fiber filled with argon gas, the effect of gas pressure on modulation instability (MI) gain is analyzed in detail. The MI gain bandwidth increases gradually as the argon gas pressure rises from 1P0 to 400P0 (P0 is one standard atmosphere), while its gain amplitude slightly decreases. Moreover, the increase of the incident light power also results in the increase of MI gain bandwidth in the Stokes or anti-Stokes region when the incident power increases from 1 W to 200 W. Making use of the optimal parameters including the higher argon gas pressure (400P0) and the incident light power (200 W), we finally obtain a 100 nm broadband MI gain. These results indicate that controlling the MI gain characteristic by changing the argon gas pressure in PCF is an effective way when the incident light source is not easy to satisfy the requirement of practical application. This method of controlling MI gain can be used in optical communication and laser shaping. [ABSTRACT FROM AUTHOR]

Even though viscosity is one of the fundamental properties of liquids, its microscopic origin is not fully understood. We determined the spatial and temporal correlation of molecular motions of water near room temperature and its temperature variation on a picosecond timescale and a subnanometer spatial scale, through high-resolution inelastic x-ray scattering measurement. The results, expressed in terms of the time-dependent pair correlation function called the Van Hove function, show that the timescale of the decay of the molecular correlation is directly related to the Maxwell relaxation time near room temperature, which is proportional to viscosity. This conclusion validates our earlier finding that the topological changes in atomic or molecular connectivity are the origin of viscosity in liquids. [ABSTRACT FROM AUTHOR]

A miniaturized 2.45 GHz permanent magnet electron cyclotron resonance (PMECR) ion source, which has the ability of producing a tens-mA H+ beam, has been built and tested at Peking University (PKU). Its plasma chamber dimension is Φ30 mm × 40 mm and the whole size of the ion source is Φ180 mm × 130 mm. This source has a unique structure with the whole source body embedded into the extraction system. It can be operated in both continuous wave (CW) mode and pulse mode. In the CW mode, more than 20 mA hydrogen ion beam at 40 kV can be obtained with the microwave power of 180 W and about 1 mA hydrogen ion beam is produced with a microwave power of 10 W. In the pulse mode, more than 50 mA hydrogen ion beam with a duty factor of 10% can be extracted when the peak microwave power is 1800 W. [ABSTRACT FROM AUTHOR]

Numerical studies on the stabilization of neoclassical tearing modes (NTMs) by electron cyclotron current drive (ECCD) have been carried out based on reduced MHD equations, focusing on the amount of the required driven current for mode stabilization and the comparison with analytical results. The dependence of the minimum driven current required for NTM stabilization on some parameters, including the bootstrap current density, radial width of the driven current, radial deviation of the driven current from the resonant surface, and the island width when applying ECCD, are studied. By fitting the numerical results, simple expressions for these dependences are obtained. Analysis based on the modified Rutherford equation (MRE) has also been carried out, and the corresponding results have the same trend as numerical ones, while a quantitative difference between them exists. This difference becomes smaller when the applied radio frequency (rf) current is smaller. [ABSTRACT FROM AUTHOR]

A combined unit, which has the ability to measure the current and emittance of the high intensity direct current (DC) ion beam, is developed at Peking University (PKU). It is a multi-slit single-wire (MSSW)-type beam emittance meter combined with a water-cooled Faraday Cup, named high intensity beam emittance measurement unit-6 (HIBEMU-6). It takes about 15 seconds to complete one measurement of the beam current and its emittance. The emittance of a 50-mA@50-kV DC proton beam is measured. [ABSTRACT FROM AUTHOR]

High current hydrogen molecular ion beam is obtained with a specially designed stainless steel liner permanent magnet 2.45-GHz electron–cyclotron resonance (ECR) ion source (PMECR II) at Peking University (PKU). To further understand the physics of the hydrogen generation process inside a plasma chamber, theoretical and experimental investigations on the liner material of the plasma chamber in different running conditions are carried out. Several kinds of materials, stainless steel (SS), tantalum (Ta), quartz, and aluminum (Al) are selected in our study. Experimental results show that stainless steel and tantalum are much better than others in generation. During the experiment, an increasing trend in fraction is observed with stainless steel liner after O2 discharge inside the ion source. Surface analyses show that the roughness change on the surface after O2 discharge may be responsible for this phenomenon. After these studies, the pure current of ions can reach 42.3 mA with a fraction of 52.9%. More details are presented in this paper. [ABSTRACT FROM AUTHOR]

We report on a systematic study of type-II Dirac fermions in a layered crystal of PdTe2. De Haas-van Alphen oscillations show a small Fermi-surface pocket with a cross section of 0.077nm-2 with a nontrivial Berry phase. First-principles calculation reveals that the nontrivial Berry phase originates from a hole pocket formed by the tilted Dirac cone. In addition, the band dispersion measured with angle-resolved photoemission spectroscopy is found to be consistent with that of a type-II Dirac cone dispersion. We propose that PdTe2 is an improved platform to host topological superconductors. [ABSTRACT FROM AUTHOR]

Temperature-dependent photoluminescence characteristics of organic-inorganic halide perovskite CH NH PbI Cl films prepared using a two-step method on ZnO/FTO substrates were investigated. Surface morphology and absorption characteristics of the films were also studied. Scanning electron microscopy revealed large crystals and substrate coverage. The orthorhombic-to-tetragonal phase transition temperature was ∼140 K. The films’ exciton binding energy was 77.6 ± 10.9 meV and the energy of optical phonons was 38.8 ± 2.5 meV. These results suggest that perovskite CH NH PbI Cl films have excellent optoelectronic characteristics which further suggests their potential usage in perovskitebased optoelectronic devices. [ABSTRACT FROM AUTHOR]

Two new 16-nor limonoids, harperspinoids A and B (1 and 2), with a unique 7/5/5/6/5 ring system, have been isolated from the plant Harrisonia perforate together with a known one, Harperforin G (3). Their structures were elucidated by NMR spectroscopy, X-ray diffraction analysis and computational modelling. Compound 1 exists as polymorphic crystals. Conformations of 1 in solution were further discussed based on the computational results. These compounds exhibited notable inhibitory activity against the 11β-HSD1 enzyme. Compound 3 had potencies for the inhibition of human 11β-HSD1 with high selectivity against 11β-HSD2 (IC50 0.58 μM, SI > 174). Molecular docking and quantitative structure-activity relationship studies revealed a mixed regulatory mechanism. [ABSTRACT FROM AUTHOR]

A letter to the editor about a case of avian influenza A(H7N9) virus infection in a pregnant woman in China is presented.

An abstract of the article "Kinetic mechanism for viral dsRNA length discrimination by MDA5 filaments," by Alys Peisley and colleagues is presented.

The anisotropic transport property was investigated in a phase separation La0.67Ca0.33MnO3 (LCMO) film grown on (001)-oriented NdGaO3 (NGO) substrate. It was found that the resistivity along the b-axis is much higher than that along the a-axis. Two resistivity peaks were observed in the temperature dependent measurement along the b-axis, one located at 91 K and the other centered at 165 K. Moreover, we also studied the response of the resistivities along the two axes to various electric currents, magnetic fields, and light illuminations. The resistivities along the two axes are sensitive to the magnetic field. However, the electric current and light illumination can influence the resistivity along the b-axis obviously, but have little effect on the resistivity along the a-axis. Based on these results, we believe that an anisotropic-strain-controlled MnO6 octahedra shear-mode deformation may provide a mechanism of conduction filaments paths along the a-axis, which leads to the anisotropic transport property. [ABSTRACT FROM AUTHOR]

We observe the spectra of molybdenum for the first time since the first wall of our experimental advanced superconducting tokamak (EAST) was changed mainly to molybdenum tiles. A large amount of molybdenum accumulated in the central plasma where the long-lived m = 1 mode instability bursts is shown. Molybdenum is proved to be the main impurity species observed during the formation and lifetime of impurity-induced long-lived m = 1 mode. This may indicate that a close relationship exists between the high-Z impurity accumulation and the occurrence of long-lived m = 1 mode in EAST plasmas. [ABSTRACT FROM AUTHOR]

The fundamental momentum conservation requirement q ~ 0 for the Raman process is relaxed in the nanocrystallites (NCs), and phonons away from the Brillouin-zone center will be involved in the Raman scattering, which is well-known as the phonon confinement effect in NCs. This usually gives a downshift and asymmetric broadening of the Raman peak in various NCs. Recently, the A′1 mode of 1L MoS2 NCs is found to exhibit a blue shift and asymmetric broadening toward the high-frequency side [Chem. Soc. Rev. 44 (2015) 2757 and Phys. Rev. B 91 (2015) 195411]. In this work, we carefully check this issue by studying Raman spectra of 1L MoS2 NCs prepared by the ion implantation technique in a wide range of ion-implanted dosage. The same confinement coefficient is used for both E′ and A′1 modes in 1L MoS2 NCs since the phonon uncertainty in an NC is mainly determined by its domain size. The asymmetrical broadening near the A′1 and E′ modes is attributed to the appearance of defect-activated phonons at the zone edge and the intrinsic asymmetrical broadening of the two modes, where the anisotropy of phonon dispersion curves along Γ–K and Γ–M is also considered. The photoluminescence spectra confirm the formation of small domain size of 1L MoS2 nanocrystallites in the ion-implanted 1L MoS2. This study provides not only an approach to quickly probe phonon dispersion trends of 2D materials away from Γ by the Raman scattering of the corresponding NCs, but also a reference to completely understand the confinement effect of different modes in various nanomaterials. [ABSTRACT FROM AUTHOR]

A new method to stabilize the rotating neoclassical tearing mode (NTM) by using both the rf current drive and the static resonant magnetic perturbation (RMP) is investigated. When a non-uniform mode rotation is induced by the RMP, the stabilization of NTM by the rf current is found to be enhanced if the RMP phase has a half period difference from that of the rf wave deposition along the helical angle. The required rf current for mode stabilization is reduced by about one third if an appropriate RMP amplitude is applied. [ABSTRACT FROM AUTHOR]

The mol­ecular structure of the centrosymmetric title compound, [Fe2(C5H5)2(C24H18)], represents a new application of cross-metathesis for the preparation of functionalized olefins containing two organometallic groups. The two benzene and attached cyclopentadienyl (Cp) rings and the double bond are almost coplanar. [ABSTRACT FROM AUTHOR]

POPULATION: Chinese ( n=131). [ABSTRACT FROM AUTHOR]

A correction to the article "Comparison of the Sagittal Profiles Among Thoracic Idiopathic Scoliosis Patients With Different Cobb Angles and Growth Potentials" that was published in a 2014 issue is presented.

Correction After publication of this work [1], we noted that we inadvertently failed to include the complete list of all coauthors, and they were not listed in the correct order. In addition, we have provided updated Authors’ Contributions and Competing interests sections. We apologize for any inconvenience these oversights may have caused. [ABSTRACT FROM AUTHOR]

Graphene free-standing film-like or paper-like materials have attracted great attention due to their intriguing electronic, optical and mechanical properties and potential application in chemical filters, molecular storage and supercapacitors. Although significant progress has been made in fabricating graphene films or paper, there is still no effective method targeting ultrathin free-standing graphene films (UFGFs). Here, we present a modified filtration assembly method to prepare these ultrathin films. With this approach, we have fabricated a series of ultrathin free-standing graphene oxide films and UFGFs, up to 40 mm in diameter, with controllable thickness from micrometre to nanoscale (approx. 40 nm) dimensions. This method can be easily scaled up and the films display excellent optical, electrical and electrochemical properties. The ability to produce UFGFs from graphene oxide with a scalable, low-cost approach should take us a step closer to real-world applications of graphene. [ABSTRACT FROM AUTHOR]

An abstract of the study "Association of Change on Insulin-Like Growth Factor (IGF)-Binding Protein 3 With Genetic Markers After a Month of Growth Hormone (GH) Therapy on Chinese Children Born With GH Deficiency" by Wei Wang et al is presented.

Directed cell motility is at the basis of biological phenomena such as development, wound healing, and metastasis. It has been shown that substrate attachments mediate motility by coupling the cell's cytoskeleton with force generation. However, it has been unclear how the persistence of cell directionality is facilitated. We show that mRNA localization plays an important role in this process, but the mechanism of action is still unknown. In this study, we show that the zipcode-binding protein 1 transports β-actin mRNA to the focal adhesion compartment, where it dwells for minutes, suggesting a means for associating its localization with motility through the formation of stable connections between adhesions and newly synthesized actin filaments. In order to demonstrate this, we developed an approach for assessing the functional consequences of β-actin mRNA and protein localization by tethering the mRNA to a specific location—in this case, the focal adhesion complex. This approach will have a significant impact on cell biology because it is now possible to forcibly direct any mRNA and its cognate protein to specific locations in the cell. This will reveal the importance of localized protein translation on various cellular processes. [ABSTRACT FROM AUTHOR]

α-functionalization of ferrocenyl alcohols by direct C-O bond activation by indoles, active methylene compounds, electron-rich arenes, anilines, alcohols, and thiols in acetic acid is described. This protocol provides a relatively green and efficient combinatorial access to ferrocene derivatives in a metal-free manner. [ABSTRACT FROM AUTHOR]

Extraintestinal pathogenic Escherichia coli (ExPEC) is an important pathogen which can infect humans and animals and cause many diseases outside the intestine. Here, we report the first draft genome sequence of a porcine ExPEC strain, PCN033, isolated from a pig with meningitis. [ABSTRACT FROM AUTHOR]

In this paper the elastic properties of SiOx film are investigated quantitatively for local fixed point and qualitatively for overall area by atomic force acoustic microscopy (AFAM) in which the sample is vibrated at the ultrasonic frequency while the sample surface is touched and scanned with the tip contacting the sample respectively for fixed point and continuous measurements. The SiOx films on the silicon wafers are prepared by the plasma enhanced chemical vapour deposition (PECVD). The local contact stiffness of the tip-SiOx film is calculated from the contact resonance spectrum measured with the atomic force acoustic microscopy. Using the reference approach, indentation modulus of SiOx film for fixed point is obtained. The images of cantilever amplitude are also visualized and analysed when the SiOx surface is excited at a fixed frequency. The results show that the acoustic amplitude images can reflect the elastic properties of the sample. [ABSTRACT FROM AUTHOR]