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• Polypharmacy use poses a serious safety concern for older adult drivers. • Data came from a large naturalistic driving study of older adults. • Drivers aged 65–79 years on average used 7.8 (±5.1) medications at enrollment. • Incidence of hard-braking events increased with the number of medications used. Polypharmacy (i.e., simultaneous use of two or more medications) poses a serious safety concern for older drivers. This study assesses the association between polypharmacy and hard braking events in older adult drivers. Data for this study came from a naturalistic driving study of 2990 older adults. Information about medications was collected through the "brown-bag review" method. Primary vehicles of the study participants were instrumented with data recording devices for up to 44 months. Multivariable negative binomial model was used to estimate the adjusted incidence rate ratios (aIRRs) and 95 % confidence intervals (CIs) of hard-braking events (i.e., maneuvers with linear deceleration rates ≥0.4 g) associated with polypharmacy. Of the 2990 participants, 2872 (96.1 %) were eligible for this analysis. At the time of enrollment, 157 (5.5 %) drivers were taking fewer than two medications, 904 (31.5 %) were taking 2–5 medications, 895 (31.2 %) were taking 6–9 medications, 571 (19.9 %) were taking 10–13 medications, and 345 (12.0 %) were taking 14 or more medications. Compared to drivers using fewer than two medications, the risk of hard-braking events increased 8 % (aIRR 1.08, 95 % CI 1.04, 1.13) for users of 2–5 medications, 12 % (aIRR 1.12, 95 % CI 1.08, 1.16) for users of 6–9 medications, 19 % (aIRR 1.19, 95 % CI 1.15, 1.24) for users of 10–13 medications, and 34 % (aIRR 1.34, 95 % CI 1.29, 1.40) for users of 14 or more medications. Polypharmacy in older adult drivers is associated with significantly increased incidence of hard-braking events in a dose–response fashion. Effective interventions to reduce polypharmacy use may help improve driving safety in older adults. [ABSTRACT FROM AUTHOR]

To produce high-performance noise- and weight-reducing A356-alloy hollow hubs, hub-rims and hubcaps were prepared separately through low-pressure die casting and joined together through retractable pin-tool friction stir welding (RPT-FSW). The effects of the pin retraction speed (6–37.5 mm/min) on the microstructural and mechanical properties were analysed. The results showed that the stirred zone (SZ) could be divided into a double stirred zone (DSZ) and single stirred zone (SSZ) within the pin retraction region. During the pin retraction stage, the DSZ underwent severe deformation and had a longer high-temperature duration, had larger recrystallised grains after the second dynamic recrystallisation, and had a finer and denser β'′ phase after dissolution and re-precipitation. In contrast, the SSZ underwent static recovery due to the low processing temperature, resulting in less-coarsened original recrystallised grains accompanied by much coarsened original β'′ precipitates. The combination of severer deformation and higher temperature resulted in coarser nanoscale Si precipitations in the DSZ than in the SSZ. Statistical data showed that β'′ precipitates dominated the variation in strength in the RPT-FSW region. As slow pin retraction and a long thermal experience coarsened the β'′ precipitates, a U-type Vickers hardness distribution instead of a W-type Vickers hardness distribution formed in the SSZ. This distribution degraded the service performance of the RPT-FSW joints. An appropriately high pin retraction speed improved the strength of the RPT-FSW joints and the fatigue life of the A356-alloy hollow hubs. • A356 alloy hollow hubs with noise and weight reduction functions were made by Retractable Pin-tool Friction Stir Welding. • Stirred zone in pin retraction zone can be divided to double stirred zone (DSZ) and single stirred zone (SSZ). • Mg/Si phase, nanoscale Si particles, grain size, and dislocation density were investigated by TEM, EBSD, X-ray diffraction. • β'′ phase dominated the variation of joint properties; higher pin retraction speed improved mechanical properties. [ABSTRACT FROM AUTHOR]

In this paper, polycrystalline cubic boron nitride (PcBN) with Ti 3 AlC 2 –Al as the compound binder was manufactured by high-temperature and high-pressure (HTHP) method. Effects of Ti 3 AlC 2 decomposition on PcBN microstructural features and mechanical properties at different sintering temperatures were systematically analyzed. Results revealed that sintering temperature of 1350 °C was critical temperature for complete Ti 3 AlC 2 decomposition under HTHP conditions. Sintering driving force improved with increasing temperature, resulting in significant enhancement of PcBN compactness. In addition, decomposition products of Ti 3 AlC 2 reacted with cBN to form TiC, TiB 2 , and AlN, improving the adhesion between cBN grains. At 1450 °C, as-prepared composites with the highest relative density value (99.6%), bending strength (586.22 MPa) and Vickers hardness (48.8 GPa) were attained. Moreover, at 1300 °C, fracture toughness of PcBN was 7.18 MPa m1/2. [ABSTRACT FROM AUTHOR]

In this study, carbon nanotubes (CNTs) have been employed as reinforcements for polycrystalline diamond (PCD) to fabricate CNTs/PCD composites at high-pressure and high-temperature (HPHT, 5.5 GPa and 1550 °C) conditions. The microstructure, phase composition, elemental distribution, and the effect of CNTs on mechanical properties of CNTs/PCD composites were systematically investigated. Vickers hardness of the sample with 1.5 wt% CNTs reached to 58.3 GPa, while flexural strength was improved to 650.8 MPa. Fracture toughness was enhanced from 5.4 MPa m1/2 to 9.1 MPa m1/2, which was 68.5% higher compared with that of the monolithic PCD composites. Furthermore, the toughening mechanism was explored, the increase of fracture toughness is attributed to the pull-out and bridging of CNTs during crack deflection. Additionally, it was concluded that sintering time for 90 s in HPHT can effectively ensure the integrity of CNTs and guarantee their toughening effects. • CNTs/PCD composites with different contents of CNTs were fabricated by HPHT. • Using multi-anvil apparatus to generate HPHT sintering conditions of 5.5 GPa, 1550 °C. • A significant improvement of fracture toughness achieved 9.1 MPa m1/2, which was 68.5% higher than that of the monolithic PCD composites. • Rapid HPHT sintering can effectively ensure the integrity of CNTs to guarantee its toughening effects. [ABSTRACT FROM AUTHOR]

• The full-length cDNA sequences of ClJHAMT and ClJHE were obtained. • Juvenile hormone could regulate the reproduction of Cyrtorhinus lividipennis. • Imidacloprid induced the reproduction of C. lividipennis via juvenile hormone. • The finding could improve the integration of C. lividipennis and insecticides. The Hemipteran predator, Cyrtorhinus lividipennis , feeds on the eggs and nymphs of rice planthoppers and leafhoppers. We previously demonstrated that sublethal concentrations of imidacloprid stimulated the reproduction of C. lividipennis. Considering the essential roles of juvenile hormone (JH) in insect reproduction, we speculated that sublethal concentrations of imidacloprid may stimulate the reproduction of C. lividipennis by regulating JH level. To test this, we cloned C. lividipennis JH acid methyl transferase (ClJHAMT) and JH esterase (ClJHE), which are responsible for JH biosynthesis and degradation genes, respectively. We then knocked down ClJHAMT by injecting dsRNA into C. lividipennis nymphs and found that emerging female adults exhibited 88.8% lower expression of the vitellogenin gene (ClVg) and the number of eggs was reduced by 41.5% as compared with controls. Silencing ClJHE increased ClVg mRNA expression by 275.0% but did not affect fecundity. A sublethal concentration of imidacloprid (LC 20) increased the JH titer in females by 35.3% and 60.6% at 24 and 48 h post-emergence, respectively. In treatments containing both imidacloprid and dsJHAMT, the silencing of CLJHAMT reduced the number of eggs produced by adult females by 21.4% as compared to the control (imidacloprid + dsGFP). Our results indicated that sublethal concentration of imidacloprid may induce C. lividipennis reproduction by upregulating JH level via JHAMT. The finding could provide valuable information for improved integration of C. lividipennis and insecticides in pest management. [ABSTRACT FROM AUTHOR]

Sintered polycrystalline diamond (PCD) was prepared via high temperature and high pressure (HTHP) process using Ti 3 SiC 2 and Si as the binder. The effect of decomposition of Ti 3 SiC 2 on comprehensive properties of PCD was investigated at different temperatures. Results show that Si formed liquid phase infiltrated diamond surface at high temperatures to inhibit diamond graphitization and to reduce defects significantly. In addition, strong covalent bond of Si-diamond was generated, which increased the strength of PCD. At suitable temperature, Ti 3 SiC 2 would partially decompose to TiC and SiC with high activity. Strong covalent bond of TiC and SiC also increased relative density and hardness of PCD, and residual Ti 3 SiC 2 enhanced the toughness of PCD. At 1500 °C, the hardness and toughness of PCD reached 54.35 GPa and 8.6 MPa m1/2, respectively, which are 19% and 82%, respectively, higher than PCD sintered at 1350 °C. [ABSTRACT FROM AUTHOR]

Highlights • Dust size distributions from the two-mode scheme and the continuous scheme are compared with AERONET observations. • A new parameterization for dust optical properties is proposed based on the continuous scheme. The shape of non-spherical dust particles is approximated using a rotational symmetric spheroid in optical property calculations. This parameterization can also be used for the two-mode scheme. • The climate model simulations show on global scales, however, the two-mode dust scheme cannot produce similar radiative forcing as the continuous scheme. Abstract Dust size distributions from the two-mode scheme and the continuous scheme are compared with AERONET observations. The two-mode dust scheme contains fine and coarse modes with fixed effective radius and effective variance for each mode. The continuous scheme takes into account the size distribution with a prognostic variation of effective radius and effective variance. The size distribution of the two-mode scheme changes with the fine/coarse mode mass ratio. However, it is impossible to make both effective radius and effective variance to match with the observed result by adjusting the fine/coarse mode mass ratio. The size distribution from the continuous scheme can be much closer to the observations. A new parameterization for dust optical properties is proposed based on the continuous scheme. The shape of non-spherical dust particles is approximated using a rotational symmetric spheroid in optical property calculations. This parameterization can also be used for the two-mode scheme. The parameterization is applied to a set of idealized one-dimensional radiative transfer calculations to investigate the sensitivity of dust radiative forcing to various attributes, including dust loading, dust solar heating rate, surface albedo, effective radius and variance. The parameterization is also evaluated in a climate model. Though at each selected region the two-mode scheme can always be tuned to approximate the results of the continuous scheme, on global scales, however, the two-mode dust scheme cannot produce similar radiative forcing as the continuous scheme and the relative error can be over 30% in several desert regions. The accurate results in radiative forcing can not be achieved by tuning the mass ratio. [ABSTRACT FROM AUTHOR]

For a variety of non-spherical particles (oriented spheroids, cuboids, triangular prisms, and hexagonal prisms), analytical transform techniques are proposed to retrieve the particle size distribution (PSD) from measured absorption spectra. The absorption efficiency of particles is calculated using the anomalous diffraction theory (ADT). We find that for each type of non-spherical particles, there exists an ADT transform pair between the size distribution and the complex absorption spectrum, which provides the physical basis for solving the inverse problem. Furthermore, the relation between the size distribution and real absorption spectrum is established by using Gaver–Stehfest׳s method. The numerical calculations show that the use of extended precision instead of double precision arithmetic can produce more reliable results at the expense of computational efficiency. Also it is shown that a small Stehfest number (standing for truncation number) tends to enhance the anti-noise level of inversion. [ABSTRACT FROM AUTHOR]

Abstract: A fundamental understanding of the water balance of a fuel cell during operation is crucial for improving the cell performance and durability. The humidification in the anode or cathode has an important effect on the flow characteristics and cell efficiency. Three-dimensional steady mathematical model based on the electrochemical, current distribution, fluid motion continuity equation, momentum and energy equation, boundary layer theory has been developed to simulate PEMFC with interdigitated flow field using the computational fluid dynamics (CFD). Effects on the current density and temperature differences have been simulated and analyzed respectively, when the humidification in the anode or cathode is from 0% to 100% respectively. The numerical results show that the humidification strongly influences the current density and temperature difference so as to affect the cell efficiency. Under the same operation conditions and low humidification conditions, anode humidification can better enhance the performance of the battery and improve the extent of PEM humidification. [Copyright &y& Elsevier]

Time series prediction is an important topic in the field of data analytics for real industrial production. However, the time series from real system usually has strong nonstationarity, which affects the generalization ability of the prediction model. An improved forecasting technique, named as fractional stochastic configuration networks (FSCN), is proposed for the prediction of nonstationary time series. FSCN is built on the basis of traditional stochastic configuration network by introducing fractional differential operator. The fractional differential technique avoids the challenge of infinite variance caused by modeling nonstationary series and the over-difference problem caused by traditional integer order difference. First, several data analysis methods are introduced to find the tendency, periodicity and probability density distribution characteristics hidden in the raw industrial data. Hurst exponent is calculated to determine the order of fractional difference to eliminate the nonstationarity of the raw data. Then FSCN network is constructed to model and forecast the sequential data. An explicit prediction uncertainty is derived to provide the confidence interval for the FSCN prediction. The proposed method is tested on a nonstationary time series benchmark dataset and a real cooling system. The experiment result demonstrates that it has a good potential prediction performance compared with several traditional prediction methods. • Stochastic configuration network is applied for nonstationary time series prediction. • Fractional difference is introduced to improve the stochastic configuration network. • The confidence interval is calculated directly with the prediction uncertainty. • The proposed methodology is verified on a real supermarket cooling system. [ABSTRACT FROM AUTHOR]

Abstract: The measurement of particle size distribution (PSD) from the extinction spectra is a challenging problem, especially for non-spherical particles. In this work, the analytical transform techniques are developed to retrieve PSD from the measured scattering data for a variety of shapes of non-spherical particle including spheroids, cuboids, triangular prisms, hexagonal prisms and elliptical cylinders. In the retrieve calculation, all particles have aligned orientations and their extinction cross sections can be adequately calculated by using the anomalous diffraction theory (ADT). It is shown that for each type of the considered non-spherical particles, there exists an ADT transform pair between the size distribution and the extinction spectrum. The inverse formula of PSD from the related ADT transform is therefore established. This result provides a new approach to the solution of the inversion problem and has the potential to be used in finding solutions for more complicated particle shapes. It is found that the solution of inverse scattering for absorbing particles can be simplified to a particular solution in which the character of absorption becomes no longer present. For spheroids, triangular prisms, and elliptical cylinders, the retrieved PSD and the corresponding true PSD always belong to one family of function, due to the scaling relation. Therefore an improper choice of inversion parameters does not significantly affect the type of mode of PSD in a retrieval process. [Copyright &y& Elsevier]

Highlights: [•] Presents dynamic entropy-based model for the detection of DoS attacks based on the theory of alive communication. [•] We construct dynamic entropy model of communication system. [•] Introduce entropy changing rate and find that dynamic entropy-based method is more sensitive in detecting anomalies. [•] ROC curves further verifies the effectiveness of dynamic entropy-based model. [•] Dynamic entropy-based model can effectively detect DoS variant attacks and can be applied to large scale network. [ABSTRACT FROM AUTHOR]

Abstract: Pear-shaped ZnO/Ag core–shell submicrospheres with good monodispersity were prepared via a seed-mediated particle growth procedure, where metal Ag (by reducing Ag+ with Sn2+) deposited on the as-prepared ZnO submicrospheres served as seeds (nucleation sites) for further growth of Ag nanoparticles. The as-prepared samples were characterized by X-ray diffraction, transmission electron microscopy, energy-dispersive X-ray spectroscopy, ultraviolet–visible and photoluminescence spectra. Structure characterization demonstrates that the ZnO/Ag composites are composed of pear-shaped wurtzite ZnO submicrosphere core and Ag nanoparticles (nanoshell). Photoluminescence indicates that Ag nanoshell can effectively inhibit the recombination of the photoinduced electrons and holes of ZnO. This is responsible for the higher photocatalytic activity of the ZnO/Ag core–shell composites. The photocatalytic performance of the prepared ZnO/Ag samples for degradation of Rhodamine B was evaluated with a comparative study. The relationship between the structure of the samples and their photocatalytic performance shows that Ag deposits can significantly enhance the photocatalytic efficiency of ZnO submicrospheres. [Copyright &y& Elsevier]