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We present a novel method to accurately determine the flux of neutrinos and antineutrinos, one of the dominant systematic uncertainty affecting current and future long-baseline neutrino experiments, as well as precision neutrino scattering experiment. Using exclusive topologies in ν (ν ¯) -hydrogen interactions, ν μ p → μ − p π + , ν ¯ μ p → μ + p π − , and ν ¯ μ p → μ + n with small hadronic energy, we achieve an overall accuracy on the relative fluxes better than 1% in the energy range covering most of the available flux. Since we cannot rely on simulations nor model corrections at this level of precision, we present techniques to constrain all relevant systematic uncertainties using data themselves. The method can be implemented using the approach we recently proposed to collect high statistics samples of ν (ν ¯) -hydrogen interactions in a low-density and high-resolution detector, which could serve as part of the near detector complex in a long-baseline neutrino experiment, as well as a dedicated beam monitoring detector. [ABSTRACT FROM AUTHOR]

The mechanism of the (d, p) reaction, which has been proven a powerful spectroscopic tool, is believed to be reasonably well understood. However, the 16O(d, p)17O reaction leading to the ground state in 17O seems to be a possible exception. It was found in the previous experiments that the 16O(d, p)17O angular distribution exhibits a rapid decline below the peak at the angle of 15 degrees. To date this abnormal behavior has not been reproduced by theoretical models. In this work we present a re-measurement of the 16O(d, p) O g. s. 17 angular distribution by using a high-precision magnetic spectrograph. Our new angular distribution shows a slower decline than the previous data do. A comparative analysis with the distorted Born approximation (DWBA), the adiabatic distorted wave approximation (ADWA) and the continuum discretized coupled channels (CDCC) method suggests that the drop of the differential cross sections at the forward angles is due to the deuteron breakup coupling effects. In addition, we extracted the spectroscopic factor (SF) and the asymptotic normalization coefficient (ANC) for the 17O ground state. [ABSTRACT FROM AUTHOR]

Abstract Bilinear pairing over elliptic curves is the key technology to construct identity based encryption schemes. An appropriate hardware design can significantly speed up pairing computation. In this paper, we present a highly-parallel hardware design for optimal ate pairing over Barreto-Naehrig curves. The proposed design exploits parallelism at different levels of the pairing algorithm, including F p and F p 2 operations as well as the operations based on F p 2 . Especially the proposed architecture of dual F p 2 units at the top level makes the pairing computation more efficient. Finally, we implement a system on chip (SoC) that contains Microblaze CPU, AXI-Lite bus and the pairing computation unit. The design is verified on a Virtex-7 FPGA device with the parameters of pairing chosen according to the Identity-Based Cryptographic Algorithms SM9 enacted by China. The results show that our design computes the optimal ate pairing of 128-bit security within 394,806 cycles, which is about 3.4 ms under the working frequency of 115 MHz, and consumes about 28 k Slices and 128 DSPs. Highlights • We design an SoC with a complete hardware unit that can compute optimal ate pairing efficiently on FPGA platform. • The proposed design exploits parallelism at different levels of the pairing algorithm. • The proposed architecture of dual F p 2 units makes the pairing computation more efficient. [ABSTRACT FROM AUTHOR]

The spin Hall effect of light (SHEL) is a transport phenomenon which shows a small spatial shift perpendicular to the refractive index gradient for a linearly polarized light passing through an interface. In this paper, we have demonstrated a three-layer structure (glass–graphene metamaterial–air) to explore the characteristics of the spin Hall effect of reflected light at the glass–graphene metamaterial interface. The effects of temperature and Fermi energy of graphene and the thickness of graphene metamaterial on the horizontal and vertical displacements of SHEL are calculated and discussed. The results show that the behavior of SHEL is very slightly temperature dependent at higher wavelength while Fermi energy has significantly changed it. We also find that the thickness of graphene metamaterial has greatly modified the horizontal beam shifts, but has slightly influence on the vertical beam shifts. Moreover, different Fermi energy lead to two dispersion regions, elliptic and hyperbolic cases. The behavior of SHEL behave differently in these two cases and can be tuned by chemical doping or gate voltage. We may find a tunable way to enhance or weaken the behavior of SHEL with our will by using the proposed simple three-layer structure. [ABSTRACT FROM AUTHOR]

A series of numerical simulations were performed to investigate the influence of side free surface on the rock fragmentation induced by single TBM disc cutter. The JH-2 model combined with a Rankine tensile cracking softening model was adopted to define the rock constitutive model to simulate the rock dynamic fracture process. The distance that allows for cracks just to extend to side free surface under a given penetration is defined as the critical distance, which distinguishes the rock fragmentation patterns between induced by disc cutter close to side free surface and conventional single cutter. The former rock fragmentation pattern is that rock chips in the form of wedge-shaped block spalling from rock specimen due to tensile cracks intersection. From the mean rolling force and the rock debris mass, the specific energy to reflect cutting efficiency was calculated for different distances to side free surface. The cutting efficiencies of former patterns are far higher that by conventional single cutter. The rock macro-fracture patterns and cutting efficiency were then compared with those obtained from linear cutting experiments. The critical distance for Baiyun granite is about 100 mm obtained from experiments, in good agreement with that deduced from numerical simulations. The height difference between the inner and outer cutterhead of the two-stage cutterhead should be more than 220 mm and the distance from first disc cutter on the inner cutterhead to free surface should be less than 100 mm for granite ground. [ABSTRACT FROM AUTHOR]

The glassy carbon electrode (GCE) modified with 5-(4-Aminophenyl)-10,15,20-triphenylporphyrin]Mn(III) (MnNH 2 TPP) and graphene oxide (GO) composite materials (GO-MnNH 2 TPP) was investigated by electrochemical impedance spectroscopy (EIS) and successfully employed for the determination of uric acid (UA). Electrochemical behaviors of UA at various electrodes including the glassy carbon electrode, GO/GCE, MnNH 2 TPP/GCE and GO-MnNH 2 TPP/GCE were measured, respectively, which showed GO-MnNH 2 TPP/GCE had better electrocatalytic activities than other electrodes under the present experimental conditions. The experimental conditions of the UA determination including the effects of scan rate, pH value and the modified amount of GO-MnNH 2 TPP on the surface of GCE were optimized when the GO-MnNH 2 TPP/GCE was used to detect UA. The electrochemical response properties of UA were studied by two electrochemical methods including the differential pulse voltammograms (DPV) and the amperometric i-t curve technique under above optimized experimental conditions. The response of GO-MnNH 2 TPP/GCE towards UA was excellent line relationship in the concentration ranges from 0.5 to 500 μM and the lowest detection limit was 0.30 μM (S/N = 3) by DPV; the amperometric i-t curve techniques also exhibited excellent line relationship in the concentration ranges from 20 to 290 μM and the lowest detection limit was 1.74 μM (S/N = 3). These results showed the GO-MnNH 2 TPP/GCE hold excellent electrocatalytic activity, good stability and high selectivity towards UA. [ABSTRACT FROM AUTHOR]

Determining the risk posed by PFAS leaching from soil to groundwater requires quantification of the magnitude and temporal/spatial variability of PFAS mass discharge from the vadose zone, which is governed in part by the concentrations of PFAS in soil porewater. Porewater concentrations are impacted and mediated by the properties of the PFAS and soil, multiple transport and fate processes, and site conditions. The objective of this research was to delineate the relationship between soil porewater concentrations and soil concentrations, based on a comprehensive model of PFAS mass distribution within a soil sample volume. Measured parameters representing solid-phase sorption and air-water interfacial adsorption are used to illustrate the impact of soil and PFAS properties on the distribution of representative PFAS between soil and soil porewater. Literature data reported for soil and soil porewater concentrations of several PFAS obtained from outdoor lysimeter experiments are used to test the distribution model. Soil-to-porewater concentration ratios predicted with the model compared very well to the measured concentration ratios. The nondimensional distribution coefficient that describes the distribution of PFAS mass amongst all domains within a soil sample was observed to be a function of PFAS molecular size. Numerical simulations conducted for a model fire-training source area were used to illustrate the ranges in magnitude of soil versus porewater concentrations for representative field conditions. The results of the measured and simulated data sets demonstrated the importance of air-water interfacial adsorption for the distribution of the longer-chain PFAS within soil samples. PFAS soil porewater concentrations are anticipated to range from ng/L to mg/L depending upon soil concentrations, which in turn depend upon the nature of the site. [Display omitted] • A comprehensive distribution model is developed for PFAS porewater concentration (C p). • The ratio between soil concentration (C t) and C p is a function of soil & PFAS properties. • The C t / C p may change during long-term leaching due to nonlinear adsorption processes. • The C t / C p changes during infiltration events due to changes in air-water interfacial area. • Air-water interfacial adsorption has a significant impact on C t / C p behavior. [ABSTRACT FROM AUTHOR]

In our previous work [B. Guo and M. Q. Xie, Optik 125 , 2137 (2014)], we found that plasma photonic crystal (PC), which proposed is a multilayer stack of alternating plasma layer and dielectric, can show negative refraction not only at the frequency edge of the band gap but also at some other frequencies which do not belong to any band gaps when the frequency of oblique incidence is below the plasma frequency by analyzing the dispersion relations. Here, in this paper, we investigate further the negative refraction in plasma PCs at below plasma frequency by studying the group and phase indices. The negative group and positive phase indices of refraction are observed at below plasma frequency for oblique incidence, which denotes the occurrence of negative refraction. Moreover, the results show that the proposed plasma PCs exhibit negative refraction in two frequency regions which is same to our previous work and the frequency regions of negative refraction can be tunable. Parameter dependence of the effects is examined and discussed. [ABSTRACT FROM AUTHOR]

The paper presents a general Control Volume model for electric field simulation in wire-plate type electrostatic precipitators, along with a new injection law for charge density. The model is validated against empirical equations and experimental data in the literature when applied to the wire-plate and point-plate configurations. The voltage current characteristics and detailed distribution of field and charge density are characterized, particularly for the case of barbed wire electrode. The effects of geometric variations, such as the sharpness of the tip and the direction of the needles with respect to the plate, are investigated. [ABSTRACT FROM AUTHOR]

Rehabilitation is crucial to improve the health status of people with disabilities. Previous studies mainly analysed the impact of health insurance on utilisation of general health services; the relationship between health insurances and rehabilitation services utilisation among Chinese people with disabilities has been long neglected. This study aimed to analyse the association between health insurance programs and rehabilitation services utilisation among disabled people. This was a cross-sectional study. The data used in this study were derived from 2021 National Household Income Survey of Disabled People and National Basic Database of People with Disabilities conducted by China Disabled Persons' Federation. Logistic regression model was used to analyse the relationship between health insurance and rehabilitation services utilisation, and the propensity score matching method was used to check the robustness of the results. (1) Disabled people insured by the Basic Medical Insurance System for Urban Employees (BMISUE) and the Basic Medical Insurance System for Urban and Rural Residents (BMISURR) were positively associated with rehabilitation service utilisation (odds ratio [OR] = 1.852, 95% confidence interval [CI]:1.268, 2.707; OR = 1.375, 95% CI: 0.962, 1.966). (2) The utilisation level of rehabilitation service among disabled people insured by BMISUE was significantly higher than those insured by BMISURR (OR = 1.355, 95% CI: 1.161, 1.581). (3) The supply of rehabilitation services at the community level was positively correlated with the utilisation by people with disabilities. Health insurance can improve the financial accessibility of using rehabilitation services, and the utilisation level will increase as the benefits level of health insurance increase. [ABSTRACT FROM AUTHOR]

Abstract: We have theoretically explored the negative refraction (NR) in one-dimensional plasma photonic crystals (PCs) consisting of plasma and dielectric materials. By using the transfer matrix method and Bloch theorem, we have studied the group velocity and we have obtained the NR in plasma PCs with the help of the group velocity. The results show that plasma PCs can also exhibit the NR although they have a periodically modulated positive permittivity ɛ and permeability μ. It is also shown that the NR in plasma PCs exhibits difference behaviour in different frequency regions, ω < ω p and ω > ω p , respectively. The parameter dependence of the effects is also examined and discussed. [Copyright &y& Elsevier]

The 74Ge(p , γ)75As reaction is believed to have a strong effect on the production of the lightest p -nucleus 74Se. The 74Ge(p , γ)75As reaction cross sections were measured in the range of E p = 2.5-4.3 MeV with an in-beam γ spectroscopy method at the 3 MV tandem accelerator of the Institute of Nuclear Science and Technology, Sichuan University. The experimental results show good agreement with previous works, and extend the measurements to the widest energies to date combined with our latest work at the 1.7 MV tandem accelerator of China Institute of Atomic Energy. Our new cross sections are compared with theoretical predictions using the TALYS and EMPIRE nuclear reaction codes. The EMPIRE-EGSM calculation presents the best description of all the experimental data, and was used to derive the reaction rates. The present rates are significantly higher than the REACLIB compilation by a factor of up to 47% within the p -process relevant temperatures. [ABSTRACT FROM AUTHOR]

Purpose/objective(s): Accuracy of patient setup for accelerated partial breast irradiation (APBI) using intensity modulated radiation therapy (IMRT) is challenging due to the low visibility of the lumpectomy cavity in planar X-ray images and CBCT. Surgical clips, chest wall, or skin surface are typically used as surrogates of the lumpectomy cavity. The correlation of these three surrogates with the lumpectomy cavity needs to be validated.Materials/methods: Twenty-five patients (12 left-sided and 13 right-sided) who underwent IMRT-APBI at our institution were included in the study. Daily CT-on-rail images were acquired. Sixteen patients had surgical clips. A total of 125 setup CT images were retrospectively analyzed, comparing the isocenter shifts aligning to the ipsilateral chest wall-lung interface, skin surface, and surgical clips with the isocenter shifts directly aligning to the lumpectomy cavity. The alignment differences (setup errors) in lateral, longitudinal, and vertical directions and 3D vector differences were reported. Two-sided, paired t-test was used for statistical analysis. The correlation of the setup errors with the volume of the ipsilateral breast, the lateral distance of the lumpectomy cavity center to the body midline, the minimum distance from the lumpectomy cavity to the chest wall, and the minimum distance to skin was analyzed using Pearson's correlation.Results: 3D vector errors for the surgical clips, chest wall, and skin surface-based alignment were 1.8+/-1.0, 4.7+/-2.9, and 3.6+/-2.1 mm, respectively. Alignment using surgical clips outperformed alignment using the chest wall (P < 0.001) and skin surface (P < 0.001). The alignment using skin surface outperformed the alignment using chest wall (P < 0.001). The 95% confidence interval for the surgical clip-based alignment was (-2.5, 2.9) mm in lateral, (-2.1, 1.6) mm in vertical, and (-2.5, 3.2) mm in longitudinal directions. For chest wall-based alignment, the 95% confidence interval was (-8.3, 5.1) mm in lateral, (-14.4, 6.7) mm in vertical, and (-6.4, 7.7) mm in longitudinal directions. For skin surface-based alignment, the 95% confidence interval was (-7.8, 6.1) mm in lateral, (-3.9, 4.2) mm in vertical, and (-5.8, 5.6) mm in longitudinal directions. To ensure coverage for 99% of the treatment fractions, a uniform setup margin of 5, 15, and 10 mm was needed for the surgical clips, chest wall, and skin surface-based alignment, respectively. Setup error using chest wall alignment has a moderate correlation (R2 = 0.45) with the minimum distance from the lumpectomy cavity to the chest wall. Breast volume, lateral distance to the midline, and minimum distance to skin all had low correlation (R2 < 0.3) with setup errors.Conclusion: For accelerated partial breast irradiation, patient setup is most accurate by using surgical clips with a mean residual error of 1.8 mm due to deformation of the lumpectomy cavity. Using skin surface or chest wall as surrogates for setup requires larger planning margins than the surgical clips. [ABSTRACT FROM AUTHOR]

Perforated plates are used in many applications such as electrostatic precipitators in environmental control systems as a method of fluid flow control. The detailed structure of perforated plates causes difficulties in the design and optimization of systems by mathematical modelling. Hence, a simplified model for the perforated plates is important. In the current work, numerical experiments based on Computational Fluid Dynamics (CFD) are carried out at a microscopic, unit cell scale. The effects of a series of parameters on the flow pattern and pressure loss are investigated, including Reynolds number, open porosity, orifice diameter, plate thickness, surface roughness and plate inclination angle. Good agreement is observed between the current predictions and empirical equations/experimental data in the literature. The pressure loss is found to be determined by the large flow structures in the expansion behind the plate. The results can be potentially used for the modelling of flow distribution in electrostatic precipitators in particular. [ABSTRACT FROM AUTHOR]

Abstract: The Cerebellar Model Articulation Controller (CMAC) possesses attractive properties of fast learning and simple computation. In application, the size of its association vector is always reduced to economize the memory requirement, greatly constraining its modeling capability. The kernel CMAC (KMAC), which provides an interpretation for the traditional CMAC from the kernel viewpoint, not only strengthens the modeling capability without increasing its complexity, but reinforces its generalization with the help of a regularization term. However, the KCMAC suffers from the problem of selecting its hyperparameter. In this paper, the Bayesian Ying–Yang (BYY) learning theory is incorporated into KCMAC, referred to as KCMAC-BYY, to optimize the hyperparameter. The proposed KCMAC-BYY achieves the systematic tuning of the hyperparameter, further improving the performance in modeling and generalization. The experimental results on some benchmark datasets show the prior performance of the proposed KCMAC-BYY to the existing representative techniques. [Copyright &y& Elsevier]

Abstract: Two-way shape memory effect of TiNiSn alloys was developed by martensite deformation. With increasing Sn content, two-way shape memory strain increased. A two-way shape memory strain of 0.83% was obtained in the Ti56Ni38Sn6 alloy after 7.6% deformation. The dependence of Sn content on two-way shape memory effect was discussed. [Copyright &y& Elsevier]

The thermal cycling stability of martensitic transformation in two different TiNi alloys processed by equal channel angular pressing (ECAP) was investigated. The transformation behavior of the as-ECAP-processed Ti49.2Ni50.8 alloy was more stable than that of Ti50.2Ni49.8 alloy. Annealing at a temperature below 500°C did not influence the thermal cycling stability of the Ti49.2Ni50.8 alloy. The relationship between thermal cycling stability and composition and annealing treatment was discussed based on the grain size evolution. [ABSTRACT FROM AUTHOR]

Background: Our previous study suggested that melanoma nuclear protein 18 (Mel-18) acted as a tumor suppressor in human breast cancer. This study was designed to investigate the clinical and prognostic significance of Mel-18 in breast cancer patients.Patients and methods: Mel-18 was detected by immunohistochemistry in paraffin-embedded tissues from 287 breast cancer patients, of which 287 were from primary cancer sites, 63 from matched adjacent noncancerous sites, and 35 from metastatic lymph nodes. Differences in Mel-18 expression and clinical characteristics were compared by χ2 test. Prognostic outcomes correlated with Mel-18 were examined using Kaplan–Meier analysis and Cox proportional hazards model.Results: The decreased Mel-18 expression is incremental depending upon the magnitude of cancer progression (P < 0.001). Mel-18 was conversely correlated with the pathological classifications (P < 0.001 for T, N, and M classifications, respectively), clinical staging (P < 0.001), and progesterone receptor (P = 0.030). Furthermore, patients with higher level of Mel-18 showed prolonged overall survivals (P < 0.001). The diminished Mel-18 expression may be a risk factor for the patients’ survival (P < 0.001).Conclusions: Lower Mel-18 expression is correlated with advanced clinicopathologic classifications and a poor overall survival in breast cancer patients. These findings suggest that Mel-18 may serve as a useful marker in prognostic evaluation for patients. [ABSTRACT FROM AUTHOR]

Abstract: Nanocrystalline/amorphous matrix composites obtained by isothermal compression at high temperatures and low strain rates were characterized using transmission electron microscopy. To study the influence of high temperature deformation on the fracture behavior and room temperature plasticity, compression tests with a constant strain rate of 1×10−4 s−1 were applied to the deformed samples. Fracture features of as-cast alloy and deformed samples were analyzed using scanning electron microscopy. Compared with the as-cast alloy, the room temperature plasticity of deformed sample is not destroyed both in the range of 370–395°C at 1×10−3 s−1 and at 395°C in 1×10−2 to 1×10−3 s−1, and deteriorated at higher temperatures and lower strain rates. Corresponding to the TEM images, the homogenously dispersed nanocrystals with small size contribute to the compressive plasticity, and the aggregated large nanoparticles destroy the plasticity of the sample after high temperature deformation. [Copyright &y& Elsevier]

Abstract: Spray dryers are of considerable importance in many industrial drying operations, yet their modelling has been relatively neglected. Here we present a summary of many years work performed at Sydney University investigating the fundamental flow behaviour in dryers and their modelling using a commercial CFD code. The key point to emerge is the need to perform three-dimensional, transient calculations and to include hindered drying and wall interaction models if important issues of flow stability and wall deposition are to be studied. This issue of the need to have proper resolution of the flow at an affordable cost is addressed. [Copyright &y& Elsevier]

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]

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]

• 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]

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]

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]

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]

Ultrasonic vibration is widely utilized in manufacturing processes mainly because acoustic field could significantly affect the metal plasticity leading to stress reduction. However, viewpoints on the influence mechanism have not reached a consensus yet. In this paper, an ultrasonic vibration assisted uniaxial tension experiment with copper foils is carried out using a specially-developed device. The results show that the extent of stress reduction increases with the increase of the vibration amplitude. Acoustic softening and stress superposition are both considered in a developed model to describe the stress reduction due to ultrasonic excitation during metal forming process. Considering that ultrasonic vibration provides the energy for dislocation sliding, acoustic softening is analyzed based on crystal plasticity theory considering ultrasonic intensity. Stress superposition, mostly induced by the additional periodic strain, is included by taking account of its proportional relationship with vibration amplitude. The calculation results from the numerical model show a good agreement with those from the experiment. These findings provide an instructive understanding of mechanism of stress reduction in ultrasonic vibration assisted metal deformation and are especially helpful for pro-actively designing ultrasonic vibration assisted metal forming processes. [ABSTRACT FROM AUTHOR]

The behaviors of negative refraction of electromagnetic waves propagation at the dielectric–magnetized plasma interface are investigated in detail. The Faraday and Voigt effects on the properties of negative refraction are calculated and discussed. The results show that the behavior of negative refraction can be tuned and controlled correspondingly due to the magneto-optical effects. The properties of negative refraction behave differently in different frequency region and the magnitude of external magnetic field. Moreover, negative refraction can be realized at the dielectric–magnetized plasma interface above the plasma frequency, which is different from the case of dielectric–plasma interface. [ABSTRACT FROM AUTHOR]

Cobalt-60 stereotactic radiosurgery (SRS) typically employs frame-based immobilization and single-fraction treatment. In some circumstances, including close proximity to critical structures, large tumor size, and retreatment, SRS must be fractionated, with mask for immobilization. We present a large institutional experience with mask-based fractionated SRS for meningioma and schwannoma. All patients treated with frameless fractionated SRS for meningioma or schwannoma between March 2017 and July 2021 at one institution were identified. Patient, tumor, and treatment variables were abstracted. The primary outcomes were one- and two-year local control (LC), which was analyzed via Kaplan-Meier analysis. This study was approved by the institution's IRB. One hundred and five patients with a total of 126 tumors were treated. The median follow-up time was 18.7 months. The median age at treatment was 66 years. Seventy-one percent of patients were female. Eighty-six percent of tumors (n=108) were meningioma, and the remaining 14% (n=18) were schwannoma. Of the 61 meningiomas for which pathological information was available, 33 were grade 1, 26 were grade 2, and 2 were grade 3. The most common indication for fractionation was proximity to critical structures (55.6% of tumors); other indications were retreatment (23.0%) and large size (21.4%). For the entire cohort, the mean maximal linear size was 34.6 mm; for tumors fractionated due to size, the mean size was 44.4 mm. The median total dose was 2,500 cGy (range: 1,950-3,000), and the median dose per fraction was 500 cGy (range: 500-700); the most common dose-fractionations were 2,500 cGy in 500 cGy per fraction (67.5% of patients) and 2,750 cGy in 550 cGy per fraction (17.5% of patients). The mean target volume was 8.62 cc (range: 0.13-120.0), and the mean maximum dose was 4,716 cGy (range: 3,200-6,000). The prescription isodose line was 50 to 59% for 84% of treatments (mean % IDL, 55%). Target coverage was 100% in all 126 cases. For lesions in proximity to the brainstem, mean brainstem maximum point dose (MPD) was 24.9 Gy and mean brainstem mean dose was 6.7 Gy. For lesions in proximity to the optic pathway, mean optic nerve MPD was 15.7 Gy, mean optic nerve mean dose was 6.4 Gy, mean optic chiasm MPD was 17.3 Gy, and mean optic chiasm mean dose was 7.5 Gy. One-year LC was 97.6% and two-year LC was 93.1%. Twenty-one percent of patients experienced acute grade 1-2 toxicity; there were no grade 3 or higher acute toxicities. Thirteen percent of patients had grade 1-2 radiation necrosis (RN); there were no cases of grade 3 or higher RN. Cobalt-60 frameless fractionated SRS for benign brain tumors offers excellent local control and minimal toxicity. Frameless fractionated SRS is technically feasible, offers excellent sparing of critical structures, and is well-tolerated. Frameless fractionated SRS is an excellent treatment option for patients with large, retreated, or critically located meningioma or schwannoma. [ABSTRACT FROM AUTHOR]

The relatively low strength of aluminum (Al) alloys and Al matrix composites at high temperatures has greatly limited their applications in aerospace and automobile areas. In this study, high-performance carbon nanotubes (CNTs)/Al composites with high room-temperature tensile strength over 500 MPa were tested at elevated temperatures up to 400 °C. Results showed that the strength of CNTs/Al composites increased with increasing CNT content up to 5 vol%. CNTs/Al composites showed improved reinforcing effects at elevated temperatures compared with those at room temperature. Consequently, the 5 vol%CNTs/Al composite achieved high tensile strength of 205 MPa when tested at 400 °C, which was superior to those values (less than 100 MPa) of most available Al matrix composites. The underlying mechanism was thoroughly discussed from the grain sizes, phase compositions, interface reaction and strengthening mechanisms at different testing temperatures. The results have revealed the excellent high-temperature properties of CNTs/Al composites and their potential use at elevated temperatures. [Display omitted] • CNTs could mitigate the strength deterioration in composites at high temperatures. • The thermal stability of CNTs/Al composite was higher than Raw Al and BM Al. • The ultimate tensile strength of CNTs/Al composite achieved 205 MPa at temperature 400 °C. • CNTs reinforcing effect at high temperatures was superior to other reinforcement. [ABSTRACT FROM AUTHOR]

The effect of hydrogen on α 2 -lamella decomposition of a Ti–46Al–2V–1Cr–0.3Ni alloy (at%) was investigated. The extent of α 2 -lamella decomposition was enhanced due to hydrogen addition, which was partly attributed to hydrogen-promoted α 2 →B2 phase transformation and α 2 -phase lamellae coarsening. When the deformation temperature rose to 1473 K, hydrogen-promoted γ-phase twinning and α 2 -phase dislocation movement played a positive role in α 2 -lamella decomposition. [ABSTRACT FROM AUTHOR]

Abstract: Superelasticity and cycling stability of an ECAP-processed Ti49.2Ni50.8 alloy were investigated as a function of annealing temperature. After annealing at 400°C for 30min, Ti3Ni4 precipitates formed to strengthen the matrix and yet the grain size kept constant. Such an annealing favors to optimize the superelasticity. [Copyright &y& Elsevier]

Abstract: We analyze here the basic philosophy of alloy design and process–structure–property paradigm in pipeline steels. Microstructure of pipeline steels of yield strength in the range of 65ksi (450MPa) to 120ksi (840MPa) was characterized and the key factors that influenced the microstructure and mechanical properties of pipeline steels were examined. Based on the experimental results and analysis, it is underscored that optimizing C and Mn contents is important to eliminate undesired microstructure and obtain high toughness in pipeline steels. Adequate amount of ferrite is necessary to ensure high deformability of high grade pipeline steels. In ultrahigh strength pipeline steels, bainite obtained through rational alloy design (Mo, B), and suitable processing route (especially high cooling rate and low end cooling temperature) is beneficial in obtaining high strength–toughness combination. [Copyright &y& Elsevier]

Abstract: Thermal desorption spectroscopy (TDS) was used to study outgassing from polycrystalline SiGe (poly-SiGe), SiC and SiO2 films used for poly-SiGe-based MEMS thin film vacuum package technology. Primary desorption products were found to be H2, H2O and CO2. The CO2 outgassing could be correlated with CF4 plasma interface cleaning used for thick SiGe PECVD, which can leave carbon at the CF4-plasma-cleaned interface. [Copyright &y& Elsevier]

Abstract: The process of hydroforming a Y-shape tube was investigated through numerical simulation and experiments. Characteristics of three different forming stages were studied. Thickness distribution of these three stages and the thickness of typical location that varies with internal pressure during forming process were analyzed when the calibration pressure was 136MPa. It is shown that thickness distribution of the leftward fillet transition region is the thickest, rightward takes the second place, the top of the protrusion is the thinnest after forming. The influence of different calibration pressures on the thickness distribution was studied through numerical simulation. It is indicated from the simulation results that with the increase of calibration pressure, the biggest thickening rate is not obviously changed; however, the highest thinning rate increased significantly. [Copyright &y& Elsevier]

Nd12Fe82B6 alloy powders were mechanically milled for various times up to 20 h in both an argon and a hydrogen atmosphere. The phase and structural changes of the alloy powders during milling were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and scanning electron microscopy (SEM) analyses. The results show that mechanical milling of the Nd12Fe82B6 alloy in hydrogen leads to disproportionation of the Nd2Fe14B phase in the alloy into H5Nd2, Fe2B, and α-Fe phases. These phases are of nano-structure, with an average crystallite size of below 20 nm. After milling in hydrogen for 20 h, the Nd12Fe82B6 alloy powders are fully decomposed, and the average crystallite size of the resulting phases are decreased to not more than 10 nm. In comparison, no phase transition takes place when milling is performed in argon, but the crystallite size of both the Nd2Fe14B and the α-Fe phase decreases steadily with increasing milling time. After milling in argon for 20 h, the average crystallite size is decreased to about 20 nm. Further, the Nd12Fe82B6 alloy powders milled in hydrogen have a smaller average particle size than those milled in argon, attributed to the hydrogen-induced decrepitation and embrittlement of the Nd12Fe82B6 alloy powders upon hydrogenation during the early stage of milling in hydrogen. [Copyright &y& Elsevier]

To evaluate the risk factors of patients with locally advanced cervical cancer (LACC) undergoing radical radiotherapy (with or without concurrent chemotherapy) and to assess the prognostic value of tumor volume regression (TVR) based on magnetic resonance imaging (MRI) in different risk groups. A retrospective analysis was performed on 176 individuals diagnosed with stage IIA-IVA cervical cancer (CC) who underwent radical intensity-modulated radiotherapy in our center between January 2012 and December 2020. The tumor volume before radiotherapy (TVp) and before brachytherapy (TVmid) were evaluated based on three-dimensional MRI images, TVR = (TVp -TVmid)/TVp × 100%. Kaplan-Meier curves were used to assess patient's overall survival (OS) and progression-free survival (PFS). Prognostic factors were identified using Cox proportional hazards models. For the entire cohort, patients with TVR ≥ 94% had better 5-year OS (82.7% vs 49.8%, p<0.001) and 5-year PFS (82.5% vs 51.1%, p<0.001) compared to TVR < 94%. Patients with TVR ≥ 94% were more likely to receive concurrent chemoradiotherapy (CCRT) than those with TVR < 94% (70.1% vs 40.5%, p<0.05). Among patients undergoing CCRT, those with a TVR ≥ 94% had a better prognosis than those with a TVR < 94%. However, among patients who received RT alone, those with TVR ≥ 94% had better PFS but no statistically significant difference in OS. Likewise, among patients with CYFRA21-1 < 7.7 ng/ml, patients with TVR ≥ 94% had a better prognosis. However, TVR was not a prognostic factor in patients with CYFRA21-1 ≥ 7.7 ng/ml. Both CYFRA21-1 (OS, PFS interaction, p<0.001) and FIGO stage (PFS interaction, p = 0.035) were found to significantly impact predictive effects of TVR. In LACC patients with CRYFA21-1 < 7.7 ng/ml who received CCRT, TVR was an important prognostic factor. However, in patients with CRYFA21-1 ≥ 7.7 ng/ml who received RT alone, the prognostic value of TVR needs to be further explored. [ABSTRACT FROM AUTHOR]