Johnstonhesselberg7988

9% and 5.7% in 1996, and 4.5% and 10.9% in 2016, respectively. Conclusion A high prevalence of severe obesity among Tehranian adults has been stabilized over the past two decades. Preventive interventions should be focused on the younger and middle-aged population, to mitigate the subsequent burden of severe obesity on Tehranian population and the healthcare system.Background Tobacco smoking is one of the most important avoidable causes of mortality from non-communicable diseases (NCDs). This study aimed to report the crude and standardized prevalence of current, ever, and secondhand smoking at national and provincial levels. Methods This study was performed through an analysis of the results of the STEPs survey 2016, which was conducted as a cross-sectional national study. The samples were selected via multistage cluster sampling and they were representative of general population aged ≥18 years in all provinces of Iran. All the data were analyzed via survey analysis while considering population weights. Age-standardized prevalence was also calculated for the Iranian national population in 2016 and the World Health Organization (WHO) Population 2000-2025. Results A total of 29963 subjects aged ≥18 years from all provinces of Iran, except for Qom, participated in this study. The age standardized prevalence of current tobacco smoking among adult males and females were 24.4% (95% CI 23.6%-25.1%) and 3.8% (95% CI 3.5%-4.1%), respectively. Among the participants, the majority of the current smokers were among those aged 45-54 years (14.5%; 95% CI 13.6%-15.5%). With increase in age, the prevalence of secondhand smoking decreased to 34.8% (95% CI 33.3%-36.7%) among people aged 18-24 years and to 22·6% (95% CI 21.0%-24.3%) among subjects over 70 years. Conclusion The result of the study can be used to inform policy makers about the status of smoking and help them to design policies for setting rules on and limiting the import of cigarettes and their components to the country.Background We aimed to present the temporal and geographical trends in the incidence of stomach cancer in the Golestan province, a high-risk area in Northern Iran. Methods This study was conducted on stomach cancer cases registered in the Golestan Population-based Cancer Registry (GPCR) during 2004-2016. Age-standardized incidence rates (ASRs) per 100000 person-years were calculated. The Joinpoint regression analysis was used to calculate the average annual percent changes (AAPC). We also calculated the contribution of population aging, population size and risk to the overall changes in incidence rates. Results Overall, 2964 stomach cancer patients were registered. The ASR of stomach cancer was significantly higher in men (26.9) than women (12.2) (P less then 0.01). There was a significant decreasing trend in incidence of stomach cancer in men (AAPC=-1.80, 95% CI -3.30 to-0.28; P=0.02). We found a higher ASR of stomach cancer in the rural (21.4) than urban (18.1) (P=0.04) population, as well as a significant decreasing trend in its rates (AAPC=-2.14, 95% CI -3.10to-1.17; P less then 0.01). The number of new cases of stomach cancer increased by 22.33% (from 215 in 2004 to 263 in 2016), of which 18.1%, 25.1% and -20.9% were due to population size, population aging and risk, respectively. Our findings suggest a higher rate for stomach cancer in eastern areas. Conclusion We found high incidence rates as well as temporal and geographical diversities in ASR of stomach cancer in Golestan, Iran. Our results showed an increase in the number of new cases, mainly due to population size and aging. Further studies are warranted to determine the risk factors of this cancer in this high-risk population.In photocatalysis, it is of general interest to understand and design wide-range light-absorbing inorganic/organic hybrid materials with an excellent photo-induced intramolecular charge-transfer (ICT) effect. To verify the role of unpaired electrons in enhancing ICT within electron-withdrawing ligand-based metal-organic frameworks (MOFs), the molecular structure, density of states (DOS), and electronic structure of strong electron-deficient pyridine-diketopyrrolopyrrole (P-DPP)-based Zn (or Cu) MOFs were calculated in Gaussian package to validate the unpaired electron ICT. The electron spin resonance technique has detected the unpaired electrons for the coordination systems containing Zn-O or Cu-O clusters and P-DPP ligand on photoexcitation. The estimated band gaps from the DOS calculation for P-DPP-Cu and P-DPP-Zn are 1.4 and 2.4 eV, respectively, showing a good agreement with the experimental UV-vis optical spectra. The partial DOS, dipole moment, and frontier orbital analysis prove that the ICT should happen from Zn-O or Cu-O clusters to P-DPP ligands. read more This research may contribute to a comprehensive understanding of electron-withdrawing ligand-induced ICT within MOFs and shed light on the design of light-absorbing MOFs with excellent ICT or conductivity.Nonmechanical nano/microscale pumps that provide precise control over flow rate without the aid of an external power source and that are capable of turning on in response to specific analytes in solution are needed for the next generation of smart micro- and nanoscale devices. Herein, a self-powered chemically driven silver micropump is reported that is based on the two-step catalytic decomposition of hydrogen peroxide, H2O2. The pumping direction and speed can be controlled by modulating the solution pH, and modeling and theory allow for the kinetics of the reaction steps to be connected to the fluid velocity. In addition, by changing the pH dynamically using glucose oxidase (GOx)-catalyzed oxidation of glucose to gluconic acid, the direction of fluid pumping can be altered in situ, allowing for the design of a glucose sensor. This work underscores the versatility of catalytic pumps and their ability to function as sensors.Small-angle neutron scattering, which has not been extensively utilized for foam characterization, can provide important insights into the microstructure of surfactant-stabilized foam. Small-angle neutron scattering in combination with several other techniques was herein employed to determine the microstructure of foams stabilized by hydroxy group-containing (C12-EtOH-βAla) and hydroxy group-free (C12-Me-βAla) surfactants of the amino acid type. Hydroxy group introduction at the amide nitrogen had no effect on the foam film thickness (∼26 nm in both cases) but increased the foam stability and suppressed draining, as hydrogen bonding between hydroxy groups and carboxylate ions increased the foam film strength. Moreover, the obtained foam films were shown to contain micelles identical to those in the bulk solution.Exciton-exciton annihilation (EEA) and Auger recombination are detrimental processes occurring in semiconductor optoelectronic devices at high carrier densities. Despite constituting one of the main obstacles for realizing lasing in semiconductor nanocrystals (NCs), the dependencies on NC size are not fully understood, especially for those with both weakly and strongly confined dimensions. Here, we use differential transmission spectroscopy to investigate the dependence of EEA on the physical dimensions of thickness-controlled 2D halide perovskite nanoplatelets (NPls). We find the EEA lifetimes to be extremely short on the order of 7-60 ps. Moreover, they are strongly determined by the NPl thickness with a power law dependence according to τ2 ∝ d5.3. Additional measurements show that the EEA lifetimes also increase for NPls with larger lateral dimensions. These results show that a precise control of the physical dimensions is critical for deciphering the fundamental laws governing the process especially in 1D and 2D NCs.In this report, we introduced poly(n-vinylpyridine) (PnVP, n = 2, 4) as an electron-donating stabilizer for small ( less then 2 nm) Au clusters and elucidated how coordinating pyridines affect the physical, optical, chemical, and catalytic properties of Au clusters. Spectroscopic measurements and theoretical calculation suggested the high electron-donating ability of PnVP. PnVP-stabilized Au clusters improved robustness in aerobic oxidation of alcohols compared to poly(N-vinyl-2-pyrrolidone)-stabilized ones, while retaining catalytic activities.The production of ammonia (NH3) from molecular dinitrogen (N2) under ambient conditions is of great significance but remains as a great challenge. Using first-principles calculations, we have investigated the potential of using a transition metal (TM) atom embedded on defective MXene nanosheets (Ti3-xC2Oy and Ti2-xCOy with a Ti vacancy) as a single-atom electrocatalyst (SAC) for the nitrogen reduction reaction (NRR). The Ti3-xC2Oy nanosheet with Mo and W embedded, and the Ti2-xC2Oy nanosheet with Cr, Mo, and W embedded, can significantly promote the NRR while suppressing the competitive hydrogen evolution reaction, with the low limiting potential of -0.11 V for W/Ti2-xC2Oy. The outstanding performance is attributed to the synergistic effect of the exposed Ti atom and the TM atom around an extra oxygen vacancy. The polarization charges of the active center are reasonably tuned by the embedded TM atoms, which can optimize the binding strength of key intermediate *N2H. The good feasibility of preparing such TM SACs on defective MXenes and the high NRR selectivity with regard to the competitive HER suggest new opportunities for driving NH3 production by MXene-based SAC electrocatalysts under ambient conditions.Future society will need more energy storage than what the current technology can deliver and also need more efficient approaches to mitigate CO2 emission and its consequent climate change. Here we report a new concept of sodium-phenanthrenequinone (Na-PQ) battery that can capture CO2 to heighten its load voltage and specific energy upon discharge and reversibly release CO2 on recharge. A mechanistic study, combining spectroelectrochemistry and theoretical calculation, reveals that CO2 is involved in the discharge reaction by bonding to the carbonyl moieties (C═O) of the reduced PQ species (PQ2- in particular), which lowers the energy of the final discharge product PQ2-CO2(Na+)2 and therefore increases the formal potential of the redox couple PQ-Na+/PQ2-CO2(Na+)2. The CO2-assisted Na-PQ battery reported here exemplifies that electrochemical energy storage would have great potential to address one of the grand challenges (i.e., CO2 mitigation, utilization, and storage) facing human society in the 21st century and beyond.The iron-catalyzed hydroarylation of allenes was accomplished by weak phenone-assistance. The C-H activation proceeded with excellent efficacy and high ortho-regioselectivity in proximity to the weakly-coordinating carbonyl group for a range of substituted phenones and allenes. Detailed mechanistic studies, including the isolation of key intermediates, the structural characterization of an iron-metallacycle and kinetic analysis, allowed the sound elucidation of a plausible catalytic working mode. This mechanistic rationale is supported by detailed computational DFT studies, which fully address multi spin state reactivity. Furthermore, in operando NMR monitoring of the catalytic reaction provided detailed insights into the mode of action of the iron-catalyzed C-H alkylation with allenes.