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Soybean cyst nematode (SCN) (Heterodera glycines Ichinohe) is a major pest of soybean [Glycine mar (L.) Merr.] in the USA. Soybean plant introduction (PI) 404198A is one of the newly identified sources that can provide a broad spectrum of resistance to SCN. The objective of this study was to identify quantitative trait loci (QTL) associated with resistance to SCN races 1, 2, and 5 in PI 404198A. Linkage groups (LGs) G and A2 were found to be associated with resistance to race 1. QTL on LG G was located on the Satt309-Satt688 region, and it explained a larger proportion of the total variation (20.2%). QTL on LG A2 was located at the Satt424-Satt632-Sat-406 region, and it accounted for a smaller proportion (9%). LGs G and B1 were shown to be associated with resistance to race 2. QTL on LG G was located on the Satt688-Satt309-Satt663 region, and it explained 12.5% of the total variation. Molecular marker Satt453 on LG B1 was found to be associated with resistance to race 2, and it explained 11% of the total variation. LGs G, B1, and N were found to be associated with resistance to race 5. QTL on LG G was located on the Satt688-Satt309-Satt163 region, and it explained 6.3% of the total variation. Molecular marker Satt453 on LG B1 was found to be associated with resistance to race 5, and it explained a larger proportion of the total variation (13%). QTL on IC N was mapped on the Satt584-Sat-280- Satt549, and it explained 9.5% of the total variation. In conclusion, soybean PI 404198A may carry rhg1 on LG G, Rhg4 on LC A2, and a QTL on LC B1. Further studies are needed to lend credibility for QTL on LG N. [ABSTRACT FROM AUTHOR]

Ultra-wideband (UWB) Microwave imaging (MWI) is a promising breast cancer detection technology which exploits the significant contrast in dielectric properties between normal breast tissue and tumor. Previously, data-independent methods: such as delay-and-sum (DAS) and space-time (ST) beamforming, have been used for microwave imaging. However; the low resolution and the poor interference suppression capability associated with the data-independent methods restrict their use in practice, especially when the noise is high and the backscattered signals are weak. In this paper, we develop two data-adaptive methods for microwave imaging, which are referred to as the robust weighted Capon beamforming (RWCB) method the amplitude and phase estimation (APES) method. Due to their data-adaptive nature, these methods outperform their data-independent counterparts in terms of improved resolution aid reduced sidelobe levels. [ABSTRACT FROM AUTHOR]

Abstract: Angular distribution of the reaction at was measured in inverse kinematics. The square of asymptotic normalization coefficient (ANC) for the virtual decay was derived to be through distorted wave Born approximation (DWBA) analysis, for the first time. According to charge symmetry, (ANC)2 for was then extracted to be . We have deduced the astrophysical S-factors and reaction rates for direct capture in at energies of astrophysical relevance using the ANC for extracted from the mirror system. [Copyright &y& Elsevier]

A hybrid system, composed of an elastic beam governed by an Euler-Bernoulli beam equation with variable coefficients and a linked rigid body governed by an ordinary differential equation, is considered. Various controllability/observability properties of the system under boundary control/observation are studied. It is shown that an open-loop smooth/singular controller of either torque control or force control is sufficient to make the system exactly controllable in arbitrarily short time duration. [ABSTRACT FROM AUTHOR]

Soybean cyst nematode (SCN) is a major soybean pest throughout the soybean growing regions in the world, including the USA. Soybean PI 90763 is an important SCN resistance source. It is resistant to several SCN populations including races 2, 3 and 5. But its genetics of resistance is not well known. The objectives of this study were to: (1) confirm quantitative trait loci (QTLs) for resistance to SCN race 3 in PI 90763 and (2) identify QTLs for resistance to SCN races 2 and 5. QTLs were searched in Hamilton × PI 90763 F2:3populations using 193 polymorphic simple sequence repeats (SSRs) covering 20 linkage groups (LGs). QTLs for resistance to SCN were identified on LGs A2, B1, E, G, J and L. The same QTL was suggested for resistance to different SCN races where their 1-LOD support intervals of QTL positions highly overlapped. The QTL on LG G was associated with resistance to races 2, 3 and 5. The QTL on LG B1 was associated with resistance to races 2 and 5. The QTL on LG J was associated with resistance to races 2 and 3. The QTLs on LGs A2 and L were associated with resistance to race 3. The QTL on LG E was associated with resistance to race 5. We conclude that LGs A2 and B1 may represent an important distinction between resistance to SCN race 3 and resistance to SCN races 2 and 5 in soybean. [ABSTRACT FROM AUTHOR]

Picosecond carrier dynamics of deep bandtail states (3.1 eV) in an unintentionallyn-doped GaN epilayer at room temperature under high excitation densities (i.e.,N0 = 1.0× 1019- 1.1× 1020 cm-3) have been investigated with nondegenerate femtosecond pump-probe (267/400 nm) reflectance (?R/R0). All ?R/R0 traces possess a ~2 ps buildup time that represents an overall time for the initial non-thermal carrier population to relax towards the continuum extremes and then into the probed tail states. We observe a saturation of ?R/R0 initial (first 10 ps) recovery rate ?i at a density of 5- 6×1019 cm-3 close to the Mott transition threshold obtained from time-integrated PL measurements. Such a saturation phenomenon has been identified as the trap-bottleneck due to the bandtail states and deep traps. AsN0 is further increased, ?i accelerates due to the onset of Auger recombination as the trap-bottleneck becomes effective. The best fit by the Auger model forN0 in the range of the mid-1019-1020 cm-3 yields an Auger coefficient ofCa~ 5.0× 10-30 cm6 s-1. [ABSTRACT FROM AUTHOR]

This paper explores the use and impact of the Internet by disabled people in China, informed by the social model of disability. Based on survey data from 122 disabled individuals across 25 provinces in China, study findings suggest that there is an emerging digital divide in the use of Internet amongst the disability community in China. Internet users in our study do not appear to be representative of most disabled people in China. For the minority of disabled people who do have access to the Internet, however, its use can lead to significantly improved frequency and quality of social interaction. Study findings further suggest that the Internet significantly reduced existing social barriers in the physical and social environment for disabled people. Implications for future research, and strategies for increasing reducing the digital divide between the minority of Internet users and the majority of disabled people in China are discussed. [ABSTRACT FROM AUTHOR]

The boundary control problem of an elastic thin plate with boundary viscoelasticity is formulated in the standard form of a linear infinite-dimensional system in the energy Hilbert space. The feedback control is designed so that the input and output are collocated. The frequency-domain approach is adopted in investigating the exponential stability of the closed-loop system. Finally, by considering the boundary viscoelasticity as damping, we establish a strong stability result based on the LaSalle invariance principle and the Hömander uniqueness theorem. [ABSTRACT FROM AUTHOR]

This article reports various challenges that have been encountered in the process of developing validated Lagrangian and Eulerian models for simulating particle agglomeration within a spray dryer. These have included the challenges of accurately measuring droplet coalescence rates within a spray, and modeling properly the gas–droplet and droplet-droplet turbulence interactions. We have demonstrated the relative versatility and ease of implementation of the Lagrangian model compared with the Eulerian model, and the accuracy of both models for predicting turbulent dispersion of droplets and the turbulent flow-field within a simple jet system. The Lagrangian and Eulerian droplet coalescence predictions are consistent with each other, which implies that the numerical aspects of each simulation are handled properly, suggesting that either approach can be used with confidence for future spray modeling. However, it is clear that considerable research must be done in the area of particle turbulence modeling and accurate measurement of particle agglomeration rates before any Computational Fluid Dynamics tool can be employed to accurately predict particle agglomeration within a spray dryer. [ABSTRACT FROM AUTHOR]

The effects of dielectric, radiative leakage and ohmic losses in CPWs on the propagation of Gaussian and sinusoidally modulated Gaussian pulses are investigated. These CPWs are assumed to be fabricated on a single-layer low-temperature co-fired ceramic (LTCC) substrate. It is shown that, based on the improved empirical formula for accurate prediction of the ohmic attenuation constant presented by Liao et al., the lossy effects in LTCC CPWs are dominated by the ohmic loss of the center and ground conductive planes in the frequency range up to 40 GHz. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 39: 94–97, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11137 [ABSTRACT FROM AUTHOR]

The distortion of pulse waves propagating in some shielded composite ferrite microstrip transmission lines (FMTLs) is studied in this paper. The mathematical treatment is based on the Galerkin’s method in the spectral domain and the fast Fourier transformation (FFT). The hybrid effects of the biasing magnetic dc field intensity and its orientation on the pulse wave distortion are examined and compared. It is shown that the pulse distortion can be effectively reduced by changing the biasing field intensity or orientation. [ABSTRACT FROM AUTHOR]

The effect of anisotropy in multilayer superstrate-substrates on the propagation of a Gaussian pulse and a sinusoidally modulated Gaussian pulse in shielded microstrip lines (MLs) has been examined. Such multilayer superstrate-substrates are made of sapphire, ferrite and perhaps biaxially anisotropic materials, characterised by both tensorial permittivity and permeability. Mathematical treatments used were based on Galerkin's method in the spectral domain and fast Fourier transformation (FFT). Parametric studies were performed to show the effects of various diverse anisotropic occurrences in the superstrate-substrates on pulse distortion, including time delay, ringing and crosstalk between signal and sensing strips. It was shown that pulse distortion could be reduced effectively by combining different anisotropies in superstrates and substrates. [ABSTRACT FROM AUTHOR]

The dispersion characteristics of the dominant mode in V-shaped microstrip lines are investigated using the finite-difference time-domain (FDTD) method. Such V-shaped microstrip lines are assumed to be fabricated on a single-layer isotropic substrate. The hybrid effects of the inclined angle of the metal wall and the permittivity of the filling material on the effective permittivity and characteristic impedance are examined and compared. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 38: 320–323, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11049 [ABSTRACT FROM AUTHOR]

Aflatoxin contamination in the field is known to be influenced by numerous factors. Drought and high temperatures are conducive to Aspergillus flavus infection and aflatoxin contamination. This article will review the application of new molecular tools to study host resistance to biotic and abiotic factors affecting preharvest aflatoxin contamination in corn and peanut. We will also summarize recent studies conducted in our laboratories to evaluate the relationship of drought tolerance and aflatoxin contamination, and discuss the progress in using genetic engineering approaches to control preharvest aflatoxin contamination. The application of molecular tools, such as proteomics, DD-RT-PCR (differential display reverse transcription-polymerase chain reaction), expressed sequence tag (EST) and gene chip technology (macro/micro-array) to study gene expression in response to drought stress, and genetic transformation, will be reviewed. We have used DD-RT-PCR to display genes expressed in peanut and corn grown under drought stress vs irrigation condition. A new program has been initiated to use EST/microarray technology to study the whole genome as influenced by drought stress in corn and peanut. We are also studying A. flavus ESTs to better understand the genetic control and regulation of toxin biosynthesis. Because of the complexity of the Aspergillus-plant (corn and peanut) interactions, better understanding of the genetic mechanisms of resistance will be needed using both conventional and molecular breeding for crop improvement and control of preharvest aflatoxin contamination. Genetic improvement of crop resistance to drought stress is one component and will provide a good perspective on the efficacy of control strategy through genetic improvement. [ABSTRACT FROM AUTHOR]

Aflatoxin contamination of corn in the field is influenced by several factors. In the southern U.S., insect populations are usually large every year. Drought caused by warmer and drier than normal weather is conducive to A. flavus infection and aflatoxin contamination of corn, Zea mays L. When loose-husked hybrids are used in the southern U.S., they accentuate insect damage and aflatoxin contamination. The development and breeding of “southern-type” hybrids is essential for control of preharvest aflatoxin contamination. Molecular biotechnology may make an impact on tackling the complexity of preharvest aflatoxin contamination of corn. Integration of crop management tactics and genetic strategies, conventional or molecular, may constrain the problem and help southern corn growers produce a quality, profitable crop. [ABSTRACT FROM AUTHOR]

The generalised exponential matrix technique (GEMT) in the spectral domain and Galerkin's approach are used to examine the constitutive parameter effects in various microstrip line structures with multilayered bianisotropic superstrate-substrates (BSS). A parametric study is performed to show the hybrid effects oF cross-coupling in different magnetic groups of symmetry (MGS) in BSS on the effective dielectric constant of guided modes for enclosed single, edge-coupled, broadside-coupled and bilateral edge-coupled geometries. [ABSTRACT FROM AUTHOR]

A comparative study was performed to examine the co(cross)-polarized reflection and transmission characteristics of multi-layer omega(chiro)ferrite slabs, with or without a backing soft and hard surface (SHS), respectively. The omegaferrite models examined here can be described by the Dmitriev's continuous groups of the symmetry: C[SUB∞v](C[SUB∞]), C[SUB2v](C[SUB2]), C[SUB2v](C[SUBs])[SUP1], and C[SUB2v](C[SUBs])[SUP2]. Based on various numerical experiments, some generalized relations governing the co(cross)-polarized reflection and transmission coefficients are found, which are related to the biasing de magnetic field as well as the orientation of all omega(chiro)ferrite particles, but independent of the incident wavelength, slab thickness or its loss. [ABSTRACT FROM AUTHOR]

The Haas - Dmnth - Wilson (HDW) (Haas et al, 1999) theoretical model was used to correlate osmotic second virial coefficient (B) values with solubility (S) values for equine serum albumin (ESA) and ovalbumin for corresponding solution conditions. The best fit from the theoretical model was compared to experimental S versus B data. B values were experimentally measured using static light scattering. Solubilities of ESA were estimated using a sitting drop method. When the experimental data for S versus B were plotted, an excellent fit for ESA was obtained according to the HDW model. The results showed that the coordination number (z) in the crystal lattice was 6, and the adjustable parameter (A) was 0.072. For ovalbumin, previously reported solubility data in aqueous ammonium sulfate solutions were utilized. The solubility data for ovalbumin were correlated with the measured B values obtained in our laboratory. The resulting best fit from the HDW model showed that z = 6 and A = 0.084. [ABSTRACT FROM AUTHOR]

We present some exact global solutions with values in unit sphere for two-dimensional Landau–Lifshitz equations with initial-boundary conditions, and obtained a continuum which can be made from those solutions of a tuft of Landau–Lifshitz equations. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Nuclear processes not only generate the energy and drive the evolution of stars, but also are responsible for the synthesis of the elements in the Universe. Helium ( 4 He, or α) is the second most abundant element after hydrogen, thus α -particle induced reactions such as (α , γ) , (α , n) and (α , p) play a crucial role in nuclear astrophysics, especially for understanding stellar helium burning. Direct measurement of the cross sections for these α -capture reactions at stellar energies is greatly hindered because of the strong Coulomb repulsion. Alpha-cluster transfer reaction is a powerful tool for investigation of astrophysical (α , γ) , (α , n) and (α , p) reactions since it can preferentially populate the natural-parity states with an α -cluster structure which dominantly contribute to these astrophysical α -capture reactions during stellar helium burning. In this review we summarize the theoretical scheme, the experimental technique, astrophysical applications and the future perspectives of such approach based on α -cluster transfer reactions. [ABSTRACT FROM AUTHOR]

Presents information on a study which analyzed the effects of auxiliary chemicals on the biodegradation of commercial polyurethanes. Characterization of auxiliary chemicals within the polymers; Procedure for the biodegradation experiment; Characterization of the polymer degradation after incubation.

The high resolution infrared emission spectrum of lithium iodide has been recorded with a Fourier transform spectrometer. A total of 1024 transmissions with Delta v = 1 for 7LiI (from v = 1 0 to v = 8 7), 387 transitions with Delta v = 2( v = 2 0 to v = 6 4 transitions with Delta v = 1 for 6LiI ( v = 1 0 to v = 5 4 have been assigned. The infrared data have been used to determine improved mass-dependent Dunham Y ground X1 + electronic state. The mass-independent Dunham U along with Born-Oppenheimer breakdown constants. Finally, all of the data were fitted to the eigenvalues of the radial Schrodinger equation containing a modified Morse potential function to determine the parameters of an effective ground state potential. ) and 504 ) coefficients for the lm coefficients were obtained lm. [ABSTRACT FROM AUTHOR]

Investigates the reactivities of titanium-carbon clusters with acetone using a triple quadrupole mass spectrometer coupled with a laser vaporization source. Degree of chemical activity toward acetone; Ability of carbon-poor clusters to break the chemical bonds of acetone; Reactive loss of carbon by the carbon-rich clusters.

The article discusses a study on the genetic analysis of two Chinese families with inherited autosomal progressive symmetrical erythrokeratoderma (PSEK). The researchers assessed the oricrin, connexin 30.3 and connexin 31 genes of the two families and revealed no mutations of these genes. It suggests that more than one genetic locus is responsible for the development of PSEK.

Dialkyl dithiophosphates selectively ring open vinyl oxetanes in excellent yields under mild reaction conditions to form useful allylic thiophosphate products with high Z-selectivity. [ABSTRACT FROM AUTHOR]

• A novel lifetime estimation framework for hybrid HVDC breakers. • Press-pack IGBT module's transient junction temperature solution based on an infinitesimal method and Cauer thermal models. • Analyzing the weakness in the hybrid HVDC breaker and the suggestions for extending the breaker lifetime are given. • The influences of the fault location, the reclosing and the current-limiting reactor on the breaker lifetime are discussed. As an important aspect of breaker reliability analysis, the lifetime of a hybrid high-voltage direct current (HVDC) breaker is estimated in this paper. Based on the equivalent thermal network, the static temperature profiles of the breaker components during normal operation are solved for using an iterative method, and the components' transient temperature profiles during short-circuit faults are computed using an infinitesimal method. Then the computed temperatures are verified via finite element analysis in COMSOL Multiphysics. Considering the influence of aging on the thermal resistances of insulated gate bipolar transistor (IGBT) modules, the lifetimes of the press-pack IGBT modules and arresters in the breaker are estimated using lifetime models and cumulative damage models. In case studies, the weakest link in the breaker and the influences of the fault location, the reclosing and the current-limiting reactor on the breaker lifetime are discussed. The results show that the arresters are the weakest breaker components, and that the fault location, reclosing and current-limiting reactor all affect the breaker lifetime. [ABSTRACT FROM AUTHOR]

Sixteen novel polymorphic microsatellite loci were developed and characterized in Glyptosternum maculatum, an endemic fish inhabiting the Yarlung Zangbo River valley, Tibet, China. These loci were developed after the enrichment of microsatellite-containing genomic DNA fragments with a subtractive hybridization protocol. The polymorphism of these loci was analysed with 36 individuals representing a geographical population. The number of alleles found at these loci ranged from 3 to 10. The observed heterozygosity and expected heterozygosity ranged from 0 to 1 and from 0.31 to 0.75, respectively. These microsatellite loci will certainly facilitate the determination of the genetic structure of G. maculatum and the conservation of its genetic resource. [ABSTRACT FROM AUTHOR]

The 12C(α,γ)16O reaction is one of the most crucial reactions in nuclear astrophysics. The E2 external capture to the 16O ground state (GS) has not been emphasized in previous analyses but may make a significant contribution to the 12C(α,γ)16O cross section depending on the value of the GS asymptotic normalization coefficient (ANC). In the present work, we determine this ANC to be 337±45 fm-1/2 through the 12C(11B,7Li)16O reaction using a high-precision magnetic spectrograph. This sheds light on the existing large discrepancy of more than 2 orders of magnitude between the previously reported ANC values. Based on the new ANC, we experimentally constrain the GS external capture and show that through interference with the high energy tail of the 2+ subthreshold state, a substantial enhancement in the GS SE2(300) factor can be obtained (70±7 keV b) compared to that of a recent review (45 keV b), resulting in an increase of the total S factor from 140 to 162 keV b, which is now in good agreement with the value obtained by reproducing supernova nucleosynthesis calculations with the solar-system abundances. This work emphasizes that the external capture contribution for the ground state transition cannot be neglected in future analyses of the 12C(α,γ)16O reaction. [ABSTRACT FROM AUTHOR]

The current study was conducted to investigate the effects of mixing ratios on anaerobic co-digestion of blackwater and kitchen organic waste. The biological methane potential (BMP) of co-digested blackwater and kitchen waste were 0.85 ± 0.07 and 0.83 ± 0.06 at volatile solids (VS) ratios of 1:2 and 1:3 whereas the BMP of blackwater alone was 0.34 ± 0.01. The hydrolysis efficiency improved from 57 ± 8% in anaerobic digestion of blackwater alone to 87 ± 8% in the blackwater/kitchen waste co-digestion condition. The methane production yield increased from 449 ± 32 Nml CH 4 /gVS for blackwater only to 680 ± 58 and 630 ± 52 Nml CH 4 /gVS at blackwater/kitchen waste VS ratios of 1:2 to 1:3. Hydrogenotrophic methanogens dominated the methanogen community under a blackwater/kitchen waste VS ratio of 1:2 condition. The results suggest that blackwater energy recovery can be improved by co-digesting blackwater with kitchen waste. Image 1 • Blackwater/Kitchen waste at VS ratios of 1:2–1:3 achieved the highest performance. • Co-digestion led to hydrolysis efficiency increase of 53% and methane yield of 51%. • Co-digestion enriched for Clostridiaceae 1 and Anaerolineaceae. • Hydrogenotrophic methanogens dominant archaea community. [ABSTRACT FROM AUTHOR]

We present the first experimental determination on the spectroscopic amplitudes (SAs) for the α -cluster in the B 11 ground state via the Li 7 (Li 6 , d) 11 B reaction using a high-precision magnetic spectrograph. This is believed to have a strong effect on the studies of α -induced reactions which are crucial in nuclear astrophysics. It is found that the previous SAs of B 11 from shell model calculations cause overestimations of up to 23% for the C 12 (α , γ) 16 O S E 2 (300) factor and up to 34% for the C 13 (α , n) 16 O S (190) factor with respect to the results from the present experimentally determined SAs. Due to the importance of these two reactions, for example the uncertainty in the C 12 (α , γ) 16 O cross section at E c.m. = 300 keV is required to be better than 10% by stellar modeling, the new S -factors could result in a potential influence on the astrophysical network calculations. [ABSTRACT FROM AUTHOR]

Describes the process of sol-gel transformation of organic/inorganic hybrid materials by torsional vibration method. Detection of the formation of aggregates of the particles; Role of the increasing amplitude of the torque to reflect the rate of the sol-gel reaction; Observation of the function of higher temperature in promoting the process of growth of particles and coagulation to form aggregates in sol-gel transformation.

The propagation of pulse waves in coplanar waveguides (CPWs) is investigated, and these CPWs are assumed to be fabricated on a single-layer low-temperature co-fired ceramic (LTCC) substrate. The input pulse wave can be a Gaussian pulse or a sinusoidally modulated Gaussian pulse. Based on the standard Galerkin's method in the spectral domain, combined with fast Fourier transform (FFT), the pulse waveform and delay in CPWs are demonstrated and compared for LTCCs with different permittivities. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 37: 32–34, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10816 [ABSTRACT FROM AUTHOR]

We report the gain, noise, and dark current characteristics of random alloy Al0.79In0.21As0.74Sb0.26 (hereafter AlInAsSb)-based avalanche photodiodes (APDs) on InP substrates. We observe, at room temperature, a low excess noise corresponding to a k value (ratio of impact ionization coefficients) of 0.018 and a dark current density of 82 μA/cm2 with a gain of 15. These performance metrics represent an order of magnitude improvement of the k-value over commercially available APDs with InAlAs and InP multiplication layers grown on InP substrates. This material is also competitive with a recently reported low noise AlAsSb on InP [Yi et al., Nat. Photonics 13, 683 (2019)], with a comparable excess noise and a room temperature dark current density almost three orders of magnitude lower at the same gain. The low excess noise and dark current of AlInAsSb make it a candidate multiplication layer for integration into a separate absorption, charge, and multiplication layer avalanche photodiode for visible to short-wavelength infrared applications. [ABSTRACT FROM AUTHOR]

We report on the demonstration of Al0.85Ga0.15As0.56Sb0.44 (hereafter, AlGaAsSb) avalanche photodiodes (APDs) with a 1000 nm-thick multiplication layer. Such a thick AlGaAsSb device was grown by a digital alloy technique to avoid phase separation. The current-voltage measurements under dark and illumination conditions were performed to determine gain for the AlGaAsSb APDs. The highest gain was ∼ 42, and the avalanche initiation occurred at 21.6 V. The breakdown voltage was found to be around −53 V. The measured dark current densities of bulk and surface components were 6.0 μA/cm2 and 0.23 μA/cm, respectively. These values are about two orders of magnitude lower than those for previously reported 1550 nm-thick AlAs0.56Sb0.44 APDs [Yi et al., Nat. Photonics 13, 683 (2019)]. Excess noise measurements showed that the AlGaAsSb APD has a low k of 0.01 (the ratio of electron and hole impact ionization coefficients) compared to Si APDs. The k of the 1000-nm AlGaAsSb APD is similar to that of the thick AlAsSb APDs (k ∼ 0.005) and 5–8 times lower than that of 170 nm-thick AlGaAsSb APDs (k ∼ 0.5–0.8). Increasing the thickness of the multiplication layer over 1000 nm can also reduce k further since the difference between electron and hole impact ionization coefficients becomes significant in this material system as the thickness of the multiplication layer increases. Therefore, this thick AlGaAsSb-based APD on an InP substrate shows the potential to be a high-performance multiplier that can be used with available short-wavelength infrared (SWIR) absorption layers for a SWIR APD. [ABSTRACT FROM AUTHOR]

Enthalpy, Entropy, and Gibb's free energy changes for the clustering reactions of Na and Pb with several important atmospheric molecules and organic solvents have been measured by using high pressure mass spectrometry (HPMS). The unusually strong bonding has been found in Na ion complexes where ligands have large high moments and polarizabilities as well as in Pb ion complexes. The enhancement of the bonding by ion-high moment, ion-induced dipole, and dispersion interactions may account for the strong bonding in some of Na ion complex systems, while the strong bonding in Pb ion complexes may results from the hybridization of 6 s and 6 p orbitals of Pb ion. [ABSTRACT FROM AUTHOR]

For short-wavelength infrared (SWIR) avalanche photodiodes, a separate absorption, charge, and multiplication design is widely used. AlInAsSb on an InP substrate is a potential multiplication layer with a lattice match to absorber candidates across the SWIR. Our new measurements demonstrate that AlInAsSb on InP is a promising multiplier candidate with a relatively low dark current density of 10−4 A/cm2 at a gain of 30; a high gain, measured up to 245 in this study; and a large differentiation of electron and hole ionization leading to a low excess noise, measured to be 2.5 at a gain of 30. These characteristics are all improvements over commercially available SWIR detectors incorporating InAlAs or InP as the multiplier. We measured and analyzed gain for multiple wavelengths to extract the ionization coefficients as a function of an electric field over the range 0.33–0.6 MV/cm. [ABSTRACT FROM AUTHOR]

The 12C(α,γ)16O reaction plays a key role in the evolution of stars with masses of M>0.55M⊙. The cross-section of the 12C(α,γ)16O reaction within the Gamow window (Ec.m.=300keV, T9=0.2) is extremely small (about 10-17 barn), which makes the direct measurement in a ground-based laboratory with existing techniques unfeasible. Up until now, the cross-sections at lower energies can only be extrapolated from the data at higher energies. However, two subthreshold resonances, located at Ex=7.117MeV and Ex=6.917MeV, make this extrapolation more complicated. In this work, the 6.917 MeV subthreshold resonance in the 12C(α,γ)16O reaction was investigated via the 12C(11B,7Li)16O reaction. The experiment was performed using the Q3D magnetic spectrograph at the HI-13 tandem accelerator. We measured the angular distribution of the 12C(11B,7Li)16O transfer reaction leading to the 6.917 MeV state. Based on the finite-range distorted wave Born approximation (FRDWBA) and coupled-reaction-channel (CRC) analysis, we derived the asymptotic normalization coefficient (ANC) of the 6.917 MeV level in 16O to be (1.10±0.29) ×1010fm-1, with which the reduced α width was computed to be 18.0±4.7keV at the channel radius of 6.5 fm. Finally, we calculated the astrophysical SE2(300) factor of the ground-state transitions to be 46.2 ± 7.7 keV b. The result for the astrophysical SE2(300) factor confirms the values obtained in various direct and indirect measurements and presents an independent examination of the most important data in nuclear astrophysics. [ABSTRACT FROM AUTHOR]

The traditional TOF-PET (Positron emission tomography) mainly uses the structure of a scintillator detector connected to a photomultiplier tube. The structure has the disadvantages that time resolution is not good enough (about 300 ps FWHM) for improving the signal-to-noise ratio of the acquisition system, which is not conducive to the detection of microtumors in the clinic and reduction in imaging time. The thickness of the scintillator is large (greater than 3 cm). Traditional PET has low geometric efficiency and sensitivity. It requires a long time to complete a full-body scan. However, the MRPC can be made into a 2.4-meter-long whole body PET. The high cost of traditional TOF-PET limits its widespread use in medical and other fields. The excellent time resolution of MRPC makes MRPC TOF-PET a good application prospect. This paper shows the time resolution of two 32-gap MRPCs with 128 μ m gap thickness on cosmic rays and 0.511 MeV photons. By using the fast front-end amplifier and waveform acquisition system, the time resolution for cosmic rays is 27 ps and the rms time accuracy per 0.511 MeV photon is 72 ps. The time resolution in terms of FWHM of the time difference between photon pairs is 239 ps FWHM. The reason why MRPC detectors have different time resolutions for cosmic rays and 0.511 MeV photons is related to the different ways different particles act and the thickness of the detector. We propose to use a Cerenkov radiator to convert gamma into ultraviolet photons and use a composite photocathode to detect, improving the detection efficiency to 6.4% for RPC. • A 4-chamber 8-gap MRPC prototype with 27 ps time resolution for cosmic rays and 239 ps FWHM time resolution for 0.511 MeV gamma is presented in this paper. • The thickness of MRPCs affects the time resolution for gamma, and time jitter caused by detector thickness is equivalent to 32 ps. Besides, the different ways different particles act with MRPCs affect the time resolution. The gamma test has a small signal amplitude and a poor signal-to-noise ratio. Therefore, the time resolutions of MRPCs for 0.511 MeV photons is worse than that for cosmic rays. • The method of increasing detection efficiency by using converters has limited improvement. Improving the efficiency by increasing the number of gas gaps will lead to poor positioning accuracy. An ultrathin, high efficiency, high time resolution RPC was proposed. By using a Cerenkov radiator to convert gamma into ultraviolet photons, and using a composite photocathode to detect, it can improve the detection efficiency to 6.4% for one gap. [ABSTRACT FROM AUTHOR]

In this study, we have demonstrated a multi-layered structure to examine how the magneto-optical effects affect the behavior of the photonic spin Hall effect (PSHE). The Faraday and Voigt effects are taken into account. The multi-layered structure is one-dimensional (1D) photonic crystal (PC) with a defective plasma layer. The properties of the PSHE in both symmetric and asymmetric defective PCs are explored. The numerical results show that the applied magnetic field and the geometries of the structures have significantly changed the characteristics of the PSHE. The transverse displacements of the H-polarization can be easily enhanced by more than ten times, while the transverse displacement of the V-polarization can be easily suppressed by a few percent based the manipulating of the external magnetic field. Moreover, the magneto-optical effects can change the optimal incident angle for the assessment of the peak transverse displacements of the PSHE. In addition, the numerical results also show that the plasma frequency, defective plasma thickness, and the geometry of the structure have greatly influenced the behavior of the PSHE. The parameter dependencies of theses effects are also calculated and discussed. [ABSTRACT FROM AUTHOR]

In this paper, dispersion corrected density functional theory (DFT-D3) with the B3LYP method and the 6–31G(d) basis set is used to study the inclusion processes of gabapentin with β-cyclodextrin and the effect of inclusion on the dehydration condensation reaction of gabapentin. The calculation results show that β-cyclodextrin and gabapentin can form stable inclusion complexes in both vacuum and water. B-β-CDs is the most stable one of four inclusion complexes. After inclusion, the dehydration condensation potential barrier of gabapentin in the β-cyclodextrin cavity is significantly increased. Notably, the reaction barrier of gabapentin in the B-β-CDs complex (a protonated active group of gabapentin with a small mouth of β-cyclodextrin and its hexatomic ring in the cavity of cyclodextrin) even reaches 331.353 kJ/mol in vacuum and 283.538 kJ/mol in water, respectively. There are two obvious increases of 223.574 kJ/mol in vacuum and 193.932 kJ/mol in water after inclusion. Thus, the inclusion complex of β-cyclodextrin with gabapentin, especially B-β-CDs, inhibits the dehydration condensation side-reaction of gabapentin most effectively. [ABSTRACT FROM AUTHOR]

The article describes the case of a 31-year-old woman who was admitted to a hospital with abdominal distention for 20 days without abdominal pain, vaginal bleeding, or other systemic symptoms. Highlights include cystic lesion with annular high echo in the right lobe of the liver according to sequent ultrasonography, space-occupying lesion in the right liver lobe revealed by magnetic resonance imaging, and the importance of early diagnosis and management for reducing maternal mortality.

Abstract: The high‐rate kinematic Precise Point Positioning (PPP) of the Global Navigation Satellite System has become an effective method for monitoring crustal deformation caused by earthquakes. In this contribution, the method of GPS/GLONASS PPP with the receiver clock modeling is applied in active seismic deformation monitoring for the first time. With the modeling method, the short‐term vertical positioning accuracy of 2–4 mm that usually cannot be obtained by standard PPP is achieved. Our PPP results confirm that the positioning accuracy is improved due to the increase of GLONASS observations compared to the GPS‐only solution. Based on the external seismic data and the high‐rate GPS/GLONASS data for the 2011 Japan earthquake and 2010 and 2015 Chile earthquakes, comparative analyses concerning receiver clock modeling are carried out. The results show that a high degree of decorrelation between the height position estimates and receiver clock offsets can be obtained by using the receiver clock modeling. The short‐term accuracy of the GPS‐based vertical displacements is improved to the level of about 4.4 mm, and the short‐term accuracy of better than 4 mm for the GPS/GLONASS‐combined vertical displacements is achievable. Furthermore, the weak vertical signals that are not detected by standard PPP can be captured with the modeling of highly stable receiver clock. [ABSTRACT FROM AUTHOR]

The plasmon excited at the surface of a thin metal film covering on a semi-infinite dielectric substrate is investigated in detailed. The surface plasmon dispersion relation is derived and presented by using the quantum hydrodynamic theory with taking into the quantum statistical and quantum diffraction effects. The effects of the thin metal film character r s and the dielectric constant ε 1 on the dispersion relations are shown and discussed, i.e., without and with quantum effects. The results show that increasing r s weakens the quantum effects while increasing ε 1 can enhance the quantum effects. In addition, the plasmon dispersion relation with quantum effects is also compared to a classical model. This simple structure proposed in the paper with quantum hydrodynamic theory can be used for yielding meaningful results for studying more complex systems related to surface plasmons. [ABSTRACT FROM AUTHOR]

This study was performed to evaluate the feasibility of double emulsion technique combined with membrane emulsification to prepare microspheres for pulmonary delivery. An attempt was made to counter the shortcomings of microspheres; unsuitable size diameters and broad size distribution. Three formulation variables were optimized in order to achieve desired particle size and narrow size distribution. Compared with microspheres prepared by conventional double emulsion technique, the microsphere morphology, aerodynamic particle size, drug encapsulation efficiency and in vitro release were characterized in detail. The particles prepared by double emulsion technique combined with membrane emulsification showed the advantage on controlling the particle size to meet the requirement of respiration, as well as on encapsulation efficiency. Overall, this strategy could be promising for the application of pulmonary delivery. [ABSTRACT FROM AUTHOR]

A method of controllable doping by ion irradiation in reduced graphene oxide (RGO) is presented, and the threshold voltage of the RGO-based field-effect transistor can be finely tuned in the range from more than 30 V to about -20 V using this approach. Evidence of doping was also provided by Raman spectroscopy and Fourier transform infrared spectroscopy. [ABSTRACT FROM AUTHOR]