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• Irradiation of monolayer graphene on Nd:YAG channel waveguides with 7.5 MeV carbon ions. • Presentation of the polarization dependency of guiding properties and Raman effect in channel waveguides. • Achievement of efficient pulsed waveguide lasers Q-switched by ion-irradiated monolayer graphene. • Demonstration of the shortest pulse duration of 38.7 ns in a larger cross-section waveguide. • Tailoring lasing performance of pulsed lasers by adjusting the TE or TM polarization of the pump laser. The transfer of two-dimensional (2D) nanomaterials as saturable absorbers to the surface of optical waveguides is extremely attractive for increasing the laser damage threshold of 2D nanomaterials and the laser power of pulsed waveguide lasers. We report on the design and fabrication of passively Q-switched waveguide lasers based on monolayer graphene covered on the surface of neodymium-doped yttrium aluminum garnet (Nd:YAG) cladding waveguides under high-energy carbon ion irradiation. The monolayer graphene is forced into close contact with the waveguide surface by energetic carbon ions, which leads to an excellent coupling of the evanescent wave with graphene. As a result, highly efficient Q-switched pulsed waveguide lasers with high output power, short pulse duration, and high repetition rate are realized under both TE and TM polarized optical pumping. Among all lasers in this experiment, the shortest pulse duration of 38.7 ns is provided by the ion-irradiated larger waveguide system under TE optical pumping. [ABSTRACT FROM AUTHOR]

• The asymmetric hydrostatic support structure can automatically center the piston rod and reduce the friction of the servo cylinder. • When the piston rod is subjected to an eccentric load, the pressure in the oil chamber rises rapidly to effectively overcome the eccentric load. • As the pressure of the oil chamber of the asymmetric hydrostatic support structure increases, the friction of the servo cylinder gradually decreases. The heavy-duty servo cylinder is the main actuator of the full-hydraulic fixed-length shear. The cylinder requires horizontal articulated mounting for accurate curve forces. The output of the curvilinear force causes the piston rod to be subjected to a dynamic bias load, and the presence of the bias load adversely affects the servo cylinder seal structure. In this paper, an asymmetric hydrostatic support structure is designed in the guide sleeve for the bias load problem of the servo cylinder, and the anti-offset capacity of the structure is theoretically studied. The oil film characteristics and oil film stiffness of the structure are deduced and analyzed. Fluent software is used to simulate, and then analyze the influence of inlet pressure, piston rod speed, eccentricity and partial load on the performance of asymmetric static pressure bearing oil film. Asymmetrical hydrostatic support structure servo hydraulic cylinder test bench is built for anti-bias load performance and friction performance experiments. The research results show that the new asymmetric hydrostatic support structure has a good effect on balancing the dynamic partial load, effectively reducing the friction of the servo cylinder and making the automatic alignment of the piston rod and the guide sleeve, which proves that the technology can be effective, increase the service life of the servo hydraulic cylinder and then improve the overall efficiency of the full hydraulic dividing shear, while broaden the application field of the heavy duty servo cylinder. [ABSTRACT FROM AUTHOR]

Copper/aluminum (Cu/Al) composites with multifunctional applications have been extensively applied in a variety of fields. Nevertheless, the formability of Cu/Al composite strips during micro flexible rolling (MFR) has not been fully investigated in the sub-millimetre range. In the present work, the microstructure, mechanical properties and formability of Cu/Al composite strips during MFR were studied. The microstructure of the annealed and rolled specimens were characterized using scanning electron microscope (SEM) and electron backscatter diffraction (EBSD), and the thickness of Cu/Al composite strips with varying thickness (CSVT) was measured by laser scanning microscope. The results show that Cu/Al composite strips annealed at 400 °C exhibit the best ductility, and the CSVT with the best forming quality is obtained when the Cu layer is contact with the upper work roll. In addition, the microstructural evolution in the downward transition zone, thinner zone, upward transition zone and thicker zone with different reduction was discussed. When the plastic strain continues to increase from thicker zone to thinner zone, the intermetallic compounds (IMCs) layer generated during annealing breaks up, and subdivision and further refinement of Al grains occurs during MFR. • Optimized annealing and rolling processes improve the forming quality of Cu/Al CSVTs. • The downward rolling process is more stable and adjustable than the upward rolling process. • The reduction greatly affects fragmentation of IMCs layer and microstructure of the matrixes. [ABSTRACT FROM AUTHOR]

Copper microchannels have been attracting more and more attention due to the increasing demands for multifunctional microcomponents in the field of micromanufacturing. In the present work, the forming of microchannels on copper foils was studied by micro rolling. Copper foils with the thickness of 0.1 mm were selected and annealed at 400, 500, 600, 700 and 800 °C for 10 min prior to micro rolling, and the formability and quality of microchannels were systematically investigated. The results show that an optimal annealing temperature of 500 °C is beneficial to the forming of microchannels with high surface quality. A series of electron backscatter diffraction (EBSD) tests were performed in order to explore the effect of annealing temperatures on the formability of copper foils during micro rolling, and the results indicate that the high forming accuracy of microchannels with copper foils annealed at 500 °C is mainly attributed to the high geometric dislocation density. Additionally, the weakening of major texture components (the Brass, S and Goss components) through optimization of heat treatment also contributes to the improvement of forming accuracy of microchannels, promoting the forming of high-quality microchannels by micro rolling process. • Optimal heat treatment optimizes the forming accuracy of microchannels of copper foils. • The microstructure evolution of copper foils is significantly affected by heat treatment. • The forming accuracy of microchannels is significantly affected by the coarse grain bands. [ABSTRACT FROM AUTHOR]

Abstract: Problem: Hundreds of laws have been implemented in the United States over the past few decades designed to reduce alcohol-impaired driving and the crashes that often result. One approach has been to lower the legally allowable alcohol concentration for drivers. We examined the effects of changes in legal BAC limit in 28 U.S. states from January, 1976 to December, 2002. Method: An interrupted time-series quasi-experimental design was used, incorporating non-alcohol-related crashes as comparisons. Four outcome measures of alcohol-related crash involvement were examined: single-vehicle nighttime, BAC=0.01–0.07, BAC=0.08–0.14, and BAC≥0.15. Missing BAC test result data were handled by using multiple imputations. Analyses involved estimation of state-specific ARIMA models, controlling for other factors affecting overall crash rates and other major DUI policy changes. Inverse variance weighting methods were used to pool results across states for the most precise underlying estimate of effect of legal BAC limits. Results: Considerable state by state variability in estimated effects was observed, but results from the pooled analyses were clear and consistent. Changes in legal BAC limits significantly affected alcohol-related fatal crash involvement for both the SVN and BAC test result measures, and the laws affected drivers at all drinking levels. Summary: An estimated 360 deaths are prevented each year in the United States as a result of the move from a 0.10 to 0.08 legal limit in recent years, and an additional 538 lives could be saved each year if the United States reduced the limit to 0.05, consistent with limits in most countries worldwide. Impact on Industry: Given the significant effects of lower legal BAC limits on fatal crash involvement, businesses should support implementation of laws that further reduce the legal BAC limit for all drivers. Furthermore, all companies should set higher standards for employees, such as a zero allowable BAC limit for driving during work time. [Copyright &y& Elsevier]

Abstract: Overexpression of drug efflux transporters such as P-glycoprotein (P-gp) enables cancer cells to develop resistance to multiple anticancer drugs. Functional inhibitors of P-gp have shown promising efficacy in early clinical trials, but their long-term safety is yet to be established. A novel approach to overcome drug resistance is to use siRNA-mediated RNA interference to silence the expression of the efflux transporter. Because P-gp plays an important role in the physiological regulation of endogenous and xenobiotic compounds in the body, it is important to deliver P-gp targeted siRNA and anticancer drug specifically to tumor cells. Further, for optimal synergy, both the drug and siRNA may need to be temporally colocalized in the tumor cells. In the current study, we investigated the effectiveness of simultaneous and targeted delivery of anticancer drug, paclitaxel, along with P-gp targeted siRNA, using poly(d,l-lactide-co-glycolide) nanoparticles to overcome tumor drug resistance. Nanoparticles were surface functionalized with biotin for active tumor targeting. Dual agent nanoparticles encapsulating the combination of paclitaxel and P-gp targeted siRNA showed significantly higher cytotoxicity in vitro than nanoparticles loaded with paclitaxel alone. Enhanced therapeutic efficacy of dual agent nanoparticles could be correlated with effective silencing of the MDR1 gene that encodes for P-gp and with increased accumulation of paclitaxel in drug-resistant tumor cells. In vivo studies in a mouse model of drug-resistant tumor demonstrated significantly greater inhibition of tumor growth following treatment with biotin-functionalized nanoparticles encapsulating both paclitaxel and P-gp targeted siRNA at a paclitaxel dose that was ineffective in the absence of gene silencing. These results suggest that that the combination of P-gp gene silencing and cytotoxic drug delivery using targeted nanoparticles can overcome tumor drug resistance. [Copyright &y& Elsevier]

Abstract: Targeted drug delivery using nanocarriers is achieved by functionalizing the carrier surface with a tissue-recognition ligand. Current surface modification methods require tedious and inefficient synthesis and purification steps, and are not easily amenable to incorporating multiple functionalities on a single surface. In this report, we describe a versatile, single-step surface functionalizing technique for polymeric nanoparticles. The technique utilizes the fact that when a diblock copolymer like polylactide–polyethylene glycol (PLA–PEG) is introduced in the oil/water emulsion used in polymeric nanoparticle formulation, the PLA block partitions into the polymer containing organic phase and PEG block partitions into the aqueous phase. Removal of the organic solvent results in the formation of nanoparticles with PEG on the surface. When a PLA–PEG–ligand conjugate is used instead of PLA–PEG copolymer, this technique permits a ‘one-pot’ fabrication of ligand-functionalized nanoparticles. In the current study, the IAASF approach facilitated the simultaneous incorporation of biotin and folic acid, known tumor-targeting ligands, on drug-loaded nanoparticles in a single step. Incorporation of the ligands on nanoparticles was confirmed by using NMR, surface plasmon resonance, transmission electron microscopy and tumor cell uptake studies. Simultaneous functionalization with both ligands significantly enhanced nanoparticle accumulation in tumors in vivo, and resulted in greatly improved efficacy of paclitaxel-loaded nanoparticles in a mouse xenograft tumor model. This new surface functionalization approach will enable the development of targeting strategies based on the use of multiple ligands on a single surface to target a tissue of interest. [Copyright &y& Elsevier]

Abstract: Introduction: We examined effects of state statutory changes in DUI fine or jail penalties for firsttime offenders from 1976 to 2002. Methods: A quasi-experimental time-series design was used (n =324 monthly observations). Four outcome measures of drivers involved in alcohol-related fatal crashes are: single-vehicle nighttime, low BAC (0.01–0.07g/dl), medium BAC (0.08–0.14g/dl), high BAC (≥0.15g/dl). All analyses of BAC outcomes included multiple imputation procedures for cases with missing data. Comparison series of non-alcohol-related crashes were included to efficiently control for effects of other factors. Statistical models include state-specific Box-Jenkins ARIMA models, and pooled general linear mixed models. Results: Twenty-six states implemented mandatory minimum fine policies and 18 states implemented mandatory minimum jail penalties. Estimated effects varied widely from state to state. Using variance weighted meta-analysis methods to aggregate results across states, mandatory fine policies are associated with an average reduction in fatal crash involvement by drivers with BAC≥0.08g/dl of 8% (averaging 13 per state per year). Mandatory minimum jail policies are associated with a decline in single-vehicle nighttime fatal crash involvement of 6% (averaging 5 per state per year), and a decline in low-BAC cases of 9% (averaging 3 per state per year). No significant effects were observed for the other outcome measures. Conclusions: The overall pattern of results suggests a possible effect of mandatory fine policies in some states, but little effect of mandatory jail policies. [Copyright &y& Elsevier]

The calcification-carbonation process is a novel cleaner production method to recover alkali and alumina from bauxite residue and obtain harmless residue with low aluminum content and no alkali. At present, this method is only limited to laboratory research and has not been put into industrial application. The reason is that the existing research only focuses on the mineral transformation of the solid phase, but lacks consideration of the concentration and availability of the extract in the liquid phase. The calcification-carbonation process is a complex hydrometallurgical series process. Without a complete continuous production line, it is difficult to evaluate the reliable concentration distribution in the system. In order to obtain the concentration distribution of Na 2 O and Al 2 O 3 in the whole calcification-carbonation process, this paper adopts a combined research method of metallurgical process simulation and experimental research based on the existing solid phase transformation theory. This method turns out to be effective and inexpensive to develop new technology at present. On the basis of the previous experimental results of solid structure transformation and parameter optimization, this study employs the material balance analysis module of METSIM software to analyze the distribution and concentration of Na 2 O and Al 2 O 3 in the calcification-carbonation process. Combined with the concentration characteristics of input and output and the experimental verification of the key steps, a multi-material circulation optimization scheme of the calcification-carbonation process through the integration of liquid material flow resources is proposed to realize the effective recovery of low-concentration Al 2 O 3 and the circulation of alkali liquor in the system. It promotes the recycling of resources and cleaner production of alumina. Image 1 • A specific scheme is designed to recover alkali and alumina from bauxite residue. • The recovered resources are enriched based on multi-material balance and circulation. • Improve the availability of recovered low-concentration components. • Promote zero discharge of pollutants and cleaner production of alumina. [ABSTRACT FROM AUTHOR]