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Introduction Most adult cigarette smokers who use e-cigarettes are dual cigarette and e-cigarette (CC-EC) users, yet little is known about relative consumption of cigarettes to e-cigarettes and any associated harm reduction. Methods Rate of substitution from cigarettes to e-cigarettes at week 6 and change in biomarkers of exposure and potential harm were examined among dual dual cigarette and e-cigarette users [64/114 (56%); 35 Black, 29 Latino] in an e-cigarette switching randomized trial. Results Dual users averaged 79% substitution of cigarettes for e-cigarettes at week 6, resulting in a reduction from baseline of 70.0 ± 54.1 cigarettes per week (p < .001). Total nicotine consumption remained stable (baseline: 1160.5 ± 1042.1 pg/mL of cotinine, week 6: 1312.5 ± 1725.9 pg/mL of cotinine, p = .47), while significant reductions were seen in the potent lung carcinogen 4-(methylnitrosamino)-1-(3-pyridul)-1-butanol (NNAL) (-55.9 ± 88.6 ng/ml, p < .001), carbon monoxide (-6.3 ± 8.6 ppm, p < .001), and self-reported respiratory symptoms (−3.3 ± 8.0, p = .002). No significant changes were found in blood pressure or spirometry. Greater substitution from cigarettes to e-cigarettes was associated with larger reductions in NNAL (r = −.29, p = .02). Conclusions The predominant dual-use pattern was characterized by regular e-cigarette and intermittent cigarette use. Findings demonstrate the short-term harm reduction potential of this dual-use pattern in Black and Latino smokers and suggest that the greatest benefit, aside from cessation of both products, is achieved by higher substitution of e-cigarettes for cigarettes. Findings need confirmation in a larger sample with longer follow-up in dual users with greater variability in the rate of substitution. ClinicalTrials.gov Identifier NCT03511001 Implications Findings suggest short-term harm reduction potential of dual cigarette-e-cigarette use for Black and Latino smokers. Results also demonstrate the heterogeneity of dual-use, with the greatest harm reduction seen in dual users with higher rates of substitution from cigarettes to e-cigarettes. Study results should be confirmed in a full clinical trial with long-term follow-up to evaluate maintenance of dual-use patterns and associated harm reduction potential over time.

Introduction Individuals with Alzheimer's disease (AD) broadly exhibit lower cardiorespiratory fitness (CRF) compared to cognitively healthy older adults. Other factors, such as increasing age and female sex, are also known to track with lower CRF levels. However, it is unclear how these factors together with AD diagnosis and genetic risk (apolipoprotein e4 ; APOE4) collectively affect CRF. Methods Our primary objective was to characterize the collective relationship of age, sex, APOE4 carrier status , and cognitive status (nondemented or AD) with two commonly reported CRF outcomes, VO2 max and oxygen uptake efficiency slope (OUES). To interrogate the unique and combined effect of age, sex, APOE4, and cognitive status on CRF, we pooled multiple datasets and tested several statistical models allowing all possible interactions. Results AD diagnosis was consistently associated with lower maximal CRF, which declined with increasing age. APOE4 was also associated with lower maximal CRF (VO2max), but only in male subjects. Submaximal CRF (OUES) was lower in APOE4 carriers of both sexes, although this difference converged in male subjects with advancing age. Discussion This multi‐cohort analysis (n = 304) suggests that APOE4 carrier status and sex are important considerations for studies that evaluate maximal and submaximal CRF.

Resistance Spot Welding (RSW) is one of the most common and dominant technologies utilized in the automotive industry to join the thin sheet metals together, and expulsion is a common phenomenon during the operation. How to ensure the high quality nugget formation and joining performance is essential to ensure the quality and integrity of structures. In this study, solid state resistance spot welding is introduced in order to prevent expulsion. The effect of welding current and welding time on the mechanical performance of the solid state RSW in terms of nugget size, tensile performance and nugget formation will be investigated experimentally by using steel sheet metals. Microstructure and micro-hardness of the nugget cross-section will be evaluated as well.

Water pollution by polychlorinated aromatic hydrocarbons has always been a global issue. In this work, we reported a synthesis of supported palladium catalysts Pd/C, Pd/CeO2, Pd/SBA-15, Pd/ZrO2,Pd/SiO2, and Pd/Al2O3 as well as their catalytic activities on hydrodechlorination (HDC) of 1,2,4,5-tetrachlorobenzene (TeCB). These Pd catalysts were characterized by Brunauer-Emmett-Teller (BET) specific surface area, Transmission electron microscopy (TEM), X-ray diffraction (XRD), energy Dispersive X-ray Fluorescence (EDXRF), CO-chemisorption, and H2-temperature programmed reduction (H2-TPR) analysis. Pd/C, Pd/CeO2 and Pd/SBA-15 catalysts showed relatively high catalytic activities. The catalytic activities were associated with dispersion of Pd, metal surface area, and reaction temperature, etc.

In this work, high-performance dye-sensitized solar cells (DSSCs) based on new low-cost visible nickel complex dye (VisDye), TiO2 nanoparticle/nanotube composites electrodes, carbon nanoparticles counter electrodes, and ionic liquids electrolytes have been fabricated. The electronic structure, optical spectroscopy, and electrochemical properties of the VisDye were studied. Experimental results indicate that it is beneficial to improve the electron transport and power conversion efficiency using the nickel complex VisDye and TiO2 nanoparticle/nanotube composites. Under optimized conditions, the solar energy conversion efficiencies were measured. The short-circuit current density (JSC), the open-circuit voltage (VOC), the fill factor (FF), and the overall efficiency () of the DSSCs are 10.01 mA/cm 2 , 516 mV, 0.68, and 3.52%, respectively. This study demonstrates that the combination of new VisDye with TiO2 nanoparticle/ nanotube composites electrodes and carbon nanoparticles counter electrodes provide a way to fabricate highly efficient dye-sensitized solar cells in low-cost production.

The hydrodechlorination performance of nickel complex catalysts, Ni[phen]2(PF6)2 and Ni[bpy]3(PF6)2, were investigated with [Bmim]Br as the ionic liquid solvent. It is proved that Ni[phen]2(PF6)2 is efficient for the hydrodechlorination of aryl chlorides under mild conditions with water as the hydrogen source. The hydrogen source of reaction is from the water which was confirmed by the deuterium incorporation experiments. Recycling experiments showed a decreasing activity of this catalyst due to a small leaching of nickel complex from the ionic liquid phase during the recycling process where n-heptane was used as the extractant. A plausible reaction route has been suggested.

We reported the catalytic hydrodechlorination (HDC) of trichlorobenzenes by an organometallic compound Pd(Phen)Cl2as a catalyst precursor. The catalyst precursor was prepared by chemical coordination reaction and characterized by FTIR and1H NMR techniques. The HDC performance of Pd(Phen)Cl2as catalyst precursor was evaluated on 1,2,3-, 1,2,4-, and 1,3,5-trichlorobenzenes (TCBs). All TCBs could be converted to dechlorination products with high conversion. Products distribution was closely related with the substrate structures and C-Cl bond energies. A reasonable reaction mechanism was also proposed.