Adsorption characteristics of sulfonamide antibiotic molecules on carbon nanotube and the effects of environment.

CONTEXT: In this paper, the adsorption characteristics of five sulfonamide antibiotic molecules on carbon nanotubes were investigated using density functional theory (DFT) calculations. The adsorption configurations of different adsorption sites were optimized, and the most stable adsorption configuration of each sulfonamide molecule was determined by adsorption energy comparison, and the relative adsorption stability of five sulfonamide molecules on carbon nanotubes was determined by comparing their adsorption energies, i.e., sulfamethazine > sulfadiazine > sulfamerazine > sulfamethoxazole > sulfanilamide. The electron densities of the adsorption configurations were then calculated to confirm that the adsorption of five sulfonamide drug molecules on carbon nanotubes should be physical adsorption. Moreover, the adsorption energy of five sulfonamide molecules on carbon nanotubes in the aqueous environment was larger than that in the vacuum even though the adsorption process remain to be physical adsorption. The adsorption characteristics of the five sulfonamide molecules in various acid-base environments were finally investigated. In contrast, the adsorption energies of the five drug molecules in acid-base environments were significantly reduced, indicating that carbon nanotubes may need to have a suitable pH range to achieve the optimal adsorption effect when they are used for the treatment of sulfonamide antibiotics. METHODS: In this paper, we use density functional theory (DFT) with PBE functional to study the adsorption properties of five sulfonamides on carbon nanotubes. The structural optimization and the calculation of electronic structural properties are carried out by CP2K package (version 7.1), adopting the DZVP-MOLOPT-SR-GTH basis set and Goedeck-Teter-Hutter (GTH) pseudo potential. Grimme's D3 correction is used to during all the calculations to correctly capture the influence of the van der Waals interactions.

Relative peripheral refraction and its role in myopia onset in teenage students.

AIM: To characterize peripheral refraction and its relationship with myopia development in a selected group of male teenage Chinese students. METHODS: This 2-year prospective cohort study randomly enrolled 85 non-myopic boys (age, 14-16y) from the Experimental Class of Air Force in China. Cycloplegic peripheral refraction was examined at 0°, ±10°, and ±20° along the horizontal visual field in the right eye at the baseline and 2-year follow-up. RESULTS: The incidence of myopia at the 2-year follow-up was 15.29% (13/85). The baseline central refraction (CR) and peripheral refraction at ±10° were significantly lower in students who developed myopia than in those who did not (P<0.05). Relative peripheral refraction (RPR) did not differ between students with and without myopia (P>0.05). At the 2-year follow-up, the RPR at ±10° and 20° nasal was significantly more hyperopic in the myopic group than in the non-myopic group. Multiple linear regression analysis indicated that the change in CR was significantly correlated with the changes in RPR at 20° nasal, 10° nasal, and 20° temporal. Multivariate Logistic regression analysis indicated that the baseline CR [odds ratio (OR): 0.092, 95% confidence interval (CI): 0.012-0.688, P=0.020] and the baseline RPR at 10° nasal (OR: 0.182, 95%CI: 0.042-0.799, P=0.024) were significantly correlated with incident myopia (Omnibus test, χ 2=10.20, P=0.006). CONCLUSION: CR change is significantly correlated with changes in RPR, and students who develop myopia have more relative peripheral hyperopia. More baseline CR and relative peripheral hyperopia at 10° nasal are protective of myopia onset.

Rational design of monolayer transition metal dichalcogenide@fullerene van der Waals photovoltaic heterojunctions with time-domain density functional theory simulations.

van der Waals heterojunctions formed by transition metal dichalcogenides (TMDs) and fullerenes are promising candidates for novel photovoltaic devices due to the excellent optoelectronic properties of both TMDs and fullerenes. However, relevant experimental and theoretical investigations remain scarce to the best of our knowledge. Herein, we have first employed static density functional theory (DFT) calculations in combination with time-domain density functional theory (TDDFT) based nonadiabatic dynamics simulations to rationally evaluate the photovoltaic performances of four TMD@fullerene heterostructures, i.e. WSe2@C60, WSe2@C70, MoTe2@C60 and MoTe2@C70, respectively. Our simulation results indicate that the C70-based heterostructures overall have better photoinduced electron transfer efficiencies than their C60-based counterparts, among which the performance of the WSe2@C70 heterostructure is the best and the electron transfer from WSe2 to C70 almost accomplishes within 1 ps. In addition, the large build-in potential of about 0.75 eV of WSe2@C70 is beneficial for the charge separation processes. Our present work not only selects the van der Waals TMD@fullerene heterojunctions that might have excellent photovoltaic properties, but also paves the way for the rational design of novel heterojunctions with better optoelectronic performances with DFT and TDDFT simulations in the future.

Refractive Change and Incidence of Myopia Among A Group of Highly Selected Senior High School Students in China: A Prospective Study in An Aviation Cadet Prerecruitment Class.

Purpose: To assess the incidence rate of myopia, refractive change, and the effects of influencing factors on a group of highly selected senior high school students in an Aviation Cadet prerecruitment class in China. Methods: A total of 800 nonmyopic, male, Grade 9 students aged 14- to 16-years old with cycloplegic refraction of -0.25 or greater diopters (D) to 1.75 D or less in both eyes were enrolled in May 2016. During their senior high school studies, students had one 20-minute physical training period a day, and they were encouraged to participate in outdoor activities during class recess without any time limits. The first follow-up was 8 months after enrollment when they were in Grade 10, and the second follow-up was 1 year after the first follow-up when they were in Grade 11. Comprehensive ocular examinations and a detailed questionnaire, which included questions about outdoor activity time, parental myopia, and near work, were completed at each follow-up. Results: The average spherical equivalent refraction (SER) of the right eyes was 0.39 ± 0.44 D at baseline, 0.16 ± 0.41 D at the first follow-up, and -0.10 ± 0.38 D at the second follow-up. The cumulative refractive change was -0.50 D (95% confidence interval [CI], -0.53 to -0.47). The cumulative incidence rate of myopia was 15.5% (124/800). Incident myopia was significantly associated with outdoor activity for more than 1 versus less than 0.5 hr/d (odds ratio [OR] = 0.272, 95% CI, 0.132-0.560), baseline refraction (OR = 0.079, 95% CI, 0.041-0.153), maternal myopia (OR = 2.251, 95% CI, 1.160-4.368), longer class time (OR =3.215, 95% CI, 1.088-9.499), frequent, continuous, and long time reading/writing (OR = 1.620, 95% CI, 1.022-2.570), and shorter reading/writing distance (OR = 1.828, 95% CI, 1.065-3.140). In multiple linear regression model, having outdoor activity for more than 1 hr/d was protective from cumulative SER decrease. A higher baseline refraction together with longer reading/writing time, frequent, continuous, and longtime reading/writing, and shorter reading/writing distance were risk factors for SER decrease. Conclusions: In this cohort of highly selected, nonmyopic students, longer outdoor activity time was a protective factor for both incident myopia and refractive change of myopic shift. The risk factors for incident myopia included lower hyperopic baseline refraction, more near work, and maternal myopia. The risk factors for refractive change of myopic shift included more hyperopic baseline refraction and more near work.

Tubular proteinuria is the dominant type of proteinuria in an elderly community population in China.

PURPOSE: To explore the types of proteinuria in the elderly population in China. METHODS: Seven hundred and fourteen elderly people (≥ 60 years old) from Tianjin, China, were selected for the study. The albumin-to-creatinine ratio and α1-microglobulin-to-creatinine ratio from morning urine samples were used as indicators of proteinuria. The prevalence of proteinuria was evaluated and the proportion of three different types of proteinuria (mixed, glomerular, and tubular) was assessed in the subjects by analyzing these indicators. RESULTS: Of the 714 subjects, 29.13 % had elevated ACR and 46.36 % had elevated MCR. The proportion of subjects with either elevated ACR or MCR was 53.78 %. The correlation between MCR and ACR was moderate (r = 0.58, R (2) = 0.34, P < 0.001). Overall, tubular proteinuria was dominant (45.83 %), followed by mixed glomerular and tubular proteinuria (35.68 %), and significantly higher than glomerular proteinuria. A diet high in salt was the independent risk factor for tubular proteinuria; physical activity was the independent risk factor for glomerular proteinuria. The risk of glomerular proteinuria was lower in males than in females, but the risk of tubular proteinuria was higher in males. CONCLUSIONS: The prevalence of tubular proteinuria was higher than that of glomerular proteinuria, and the risk factors are different, in the elderly in China; therefore, tubular damage markers should get more attention in the overall population.

Methodological evaluation and comparison of five urinary albumin measurements.

BACKGROUND: Microalbuminuria is an indicator of kidney damage and a risk factor for the progression kidney disease, cardiovascular disease, and so on. Therefore, accurate and precise measurement of urinary albumin is critical. However, there are no reference measurement procedures and reference materials for urinary albumin. METHODS: Nephelometry, turbidimetry, colloidal gold method, radioimmunoassay, and chemiluminescence immunoassay were performed for methodological evaluation, based on imprecision test, recovery rate, linearity, haemoglobin interference rate, and verified reference interval. Then we tested 40 urine samples from diabetic patients by each method, and compared the result between assays. RESULTS: The results indicate that nephelometry is the method with best analytical performance among the five methods, with an average intraassay coefficient of variation (CV) of 2.6%, an average interassay CV of 1.7%, a mean recovery of 99.6%, a linearity of R=1.00 from 2 to 250 mg/l, and an interference rate of <10% at haemoglobin concentrations of <1.82 g/l. The correlation (r) between assays was from 0.701 to 0.982, and the Bland-Altman plots indicated each assay provided significantly different results from each other. CONCLUSION: Nephelometry is the clinical urinary albumin method with best analytical performance in our study.