52 research outputs found

    Coupled Oxidation-Extraction Desulfurization : A Novel Evaluation for Diesel Fuel

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    This work was financially supported by the National Science Foundation of China (21176021, 21276020, 2187081257). We extend our appreciation to the Deanship of Scientific Research at King Saud University for funding the work, through Research Group Project No. RG-1436-026.Peer reviewedPostprin

    Gene transfer of mutant mouse cholinesterase provides high lifetime expression and reduced cocaine responses with no evident toxicity

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    Gene transfer of a human cocaine hydrolase (hCocH) derived from butyrylcholinesterase (BChE) by 5 mutations (A199S/F227A/S287G/A328W/Y332G) has shown promise in animal studies for treatment of cocaine addiction. To predict the physiological fate and immunogenicity of this enzyme in humans, a comparable enzyme was created and tested in a conspecific host. Thus, similar mutations (A199S/S227A/S287G/A328W/Y332G) were introduced into mouse BChE to obtain a mouse CocH (mCocH). The cDNA was incorporated into viral vectors based on: a) serotype-5 helper-dependent adenovirus (hdAD) with ApoE promoter, and b) serotype-8 adeno-associated virus with CMV promoter (AAV-CMV) or multiple promoter and enhancer elements (AAV-VIP). Experiments on substrate kinetics of purified mCocH expressed in HEK293T cells showed 30-fold higher activity (U/mg) with (3)H-cocaine and 25% lower activity with butyrylthiocholine, compared with wild type BChE. In mice given modest doses of AAV-CMV-mCocH vector (0.7 or 3 × 10(11) particles) plasma hydrolase activity rose 10-fold above control for over one year with no observed immune response. Under the same conditions, transduction of the human counterpart continued less than 2 months and antibodies to hCocH were readily detected. The advanced AAV-VIP-mCocH vector generated a dose-dependent rise in plasma cocaine hydrolase activity from 20-fold (10(10) particles) to 20,000 fold (10(13) particles), while the hdAD vector (1.7 × 10(12) particles) yielded a 300,000-fold increase. Neither vector caused adverse reactions such as motor weakness, elevated liver enzymes, or disturbance in spontaneous activity. Furthermore, treatment with high dose hdAD-ApoE-mCocH vector (1.7 × 10(12) particles) prevented locomotor abnormalities, other behavioral signs, and release of hepatic alanine amino transferase after a cocaine dose fatal to most control mice (120 mg/kg). This outcome suggests that viral gene transfer can yield clinically effective cocaine hydrolase expression for lengthy periods without immune reactions or cholinergic dysfunction, while blocking toxicity from drug overdose

    Effect of Mix Proportion Parameters on Behaviors of Basalt Fiber RPC Based on Box-Behnken Model

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    Basalt fibers are widely used in the modification of concrete materials due to its excellent mechanical properties and corrosion resistance. In this study, the basalt fibers were used to modify reactive powder concrete (RPC). The effect of four mix proportion parameters on the working and mechanical properties of basalt fiber reactive powder concrete (BFRPC) was evaluated by the response surface methodology (RSM). The fluidity, flexural and compressive strength were tested and evaluated. A statistically experimental model indicated that D (the silica fume to cement ratio) was the key of interactions between factors, affecting other factors and controlling properties of BFRPC. The increase in basalt fiber content had a remarkable effect on increasing the flexural and compressive strength when D = 0.2. The addition of basalt fiber obviously improved the mechanical properties of RPC. While when D = 0.4, the decrease of fiber content and the increase of quartz sand content could increase the compressive strength

    On‐Chip Tightly Confined Guiding and Splitting of Surface Acoustic Waves Using Line Defects in Phononic Crystals

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    Abstract Phononic crystals (PnCs) exhibit acoustic properties that are not usually found in natural materials, which leads to the possibility of new devices for the complex manipulation of acoustic waves. In this article, a micron‐scale phononic waveguide constructed by line defects in PnCs to achieve on‐chip, tightly confined guiding, bending, and splitting of surface acoustic waves (SAWs) is reported. The PnC is made of a square lattice of periodic nickel pillars on a piezoelectric substrate. The PnC lattice constant, pillar diameter, and pillar height are set to 10, 7.5, and 3.2 ”m, respectively, leading to a complete bandgap centered at 195 MHz. Interdigitated transducers are monolithically integrated on the same substrate for SAW excitation. The guiding, bending, and splitting of SAWs in the phononic waveguide are experimentally observed through measurement of the out‐of‐plane displacement fields using a scanning optical interferometer. The combination of destructive interference due to the Bragg bandgap and the interaction of the propagating wave with the pillars around the channel results in a tight confinement of the displacement field. The proposed phononic waveguides demonstrate the feasibility of precise local manipulation of SAW that is essential for emerging frontier applications, notably for phonon‐based classical and quantum information processing

    Oxidative Desulfurization of Gasoline by Ionic Liquids Coupled with Extraction by Organic Solvents

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    In this work, desulfurization of real fluidized catalytic cracking (FCC) gasoline was investigated in dual steps; first in oxidative desulfurization (ODS) using imidazolium and pyrrolidonium based BrĂžnsted acidic ionic liquids (ILs) as solvent and catalyst and hydrogen peroxide as oxidant. In second step, extractive desulfurization took place using organic solvents of furfural, furfural alcohol and ethylene glycol. Variety of factors such as temperature, time, mass ratio of oil/ILs and regeneration and recycling of ILs, multiple-step desulfurization of ILs and organic solvents and solvent/oil ratio were also investigated. The S-content was significantly decreased to ca. 18 ppm from initial S-content of 260 ppm with a total S-removal of ca. 95% in one-step ODS using pyrrolidonium based ILs coupled with five-step extraction desulfurization (EDS) using furfural alcohol as extractant. This work shows that oxidative desulfurization using ionic liquids coupled with extractive desulfurization using organic solvents is a potential method to produce clean gasoline

    Temporal variations of the association between summer season heat exposure and hospitalizations for renal diseases in Queensland, Australia, 1995–2016

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    To examine the temporal trends of the association between heat exposure and hospitalizations for renal disease in Queensland, Australia, between the summer season of 1 December 1995 and 31 December 2016. A total of 238 427 de-identified hospitalization records for renal disease were collected from Queensland Health. Meteorological data was obtained from the Scientific Information for Land Owners. Summer season means four consecutive months with higher daily mean temperatures. We conducted a time-stratified case-crossover study using conditional quasi-Poisson regression model and applied a time-varying distributed lag non-linear model were used to evaluate the temporal trends of the associations between 1 °C increase in daily mean temperatures (over 0–10 lags) and hospitalizations for renal diseases. We also conducted stratified analyses by sex, age, climate zone, socioeconomic status, and cause-specific renal diseases. Overall, the associations between high temperature and hospitalizations for renal diseases showed a decreasing trend during the summer seasons from 1995 to 2016. However, the heat-related effects in males increased from 3.0% (95% CI: 2.2%, 3.9%) in 1995 to 4.8% (95% CI: 3.9%, 5.6%) in 2016. In the elderly cohort (both sexes), there was a similar increase over time 2.0% (95% CI: 1.0%, 3.0%) in 1995 to 6.3% (95% CI: 5.4%, 7.3%) in 2016. People living in hotter climate zones and those living in relatively socioeconomically disadvantaged areas also showed an increasing trend. In the cause-specific disease analysis, the increasing trend was found in renal failure, with heat-related effects increased from 3.45% (95% CI: 2.31%, 4.60%) in 1995 to 8.19% (95% CI: 7.03%, 9.36%) in 2016. Although the association between temperature and hospitalizations for renal diseases showed a decreasing trend in Queensland’s hot season between 1995 and 2016, the susceptibility to high temperatures is increasing in males, the elderly of both sexes, those living in hotter climate areas, and socioeconomically disadvantaged areas. This increasing trend of susceptibility is a great concern and indicates a strong need for targeted public health promotion campaigns
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