Fabrication of a novel separation‐free heterostructured photocatalyst with enhanced visible light activity in photocatalytic degradation of antibiotics

A novel separation‐free poly(N,N′-dimethylacrylamide)-titanium dioxide/copper sulfide (PDMAA-TiO2/CuS) hydrogel photocatalyst with the synergistic effect of adsorption and photocatalysis has been successfully developed by a facile two-step method involving a homogeneous polymerization...

Tailoring g-C3N4 with Lanthanum and Cobalt Oxides for Enhanced Photoelectrochemical and Photocatalytic Activity

Herein, the synthesis, characterization, and photoelectrochemical and photocatalytic characteristics of hydrothermally prepared La2O3–g-C3N4, CoO–g-C3N4, and La2O3–CoO–g-C3N4 are discussed. The XRD analysis and crystalline phases unveiled the impregnation of La2O3 and CoO into g-C3N4. The microscopic analysis supports the formation of g-C3N4 nanoflakes and La2O3 and CoO nanoparticles embedded homogeneously in the La2O3–CoO–g-C3N4 nanocomposite, whereas the EDX comprehended their respective elemental composition and ratios. A bandgap energy of 2.38 eV for La2O3–CoO–g-C3N4 was calculated using the Tauc plot method, complementing high visible-light activity. The solar-driven water-splitting reaction exhibited significant photocurrent efficiency (~3.75 mA/cm2), augmenting the hydrogen generation by La2O3–CoO–g-C3N4 compared to that by pure g-C3N4, La2O3–g-C3N4, and CoO–g-C3N4 in 0.5 M Na2SO4 electrolyte. The synergistic effect of La2O3 and CoO impregnation with g-C3N4 led to effective division of the photogenerated charge transporters, enhancing the photocatalytic hydrogen generation by the photocatalysts. Furthermore, photocatalytic pollutant removal, namely greater than 90% decomposition of methylene blue (MB) from water, was investigated with a pseudo-first-order reaction kinetics under 1 sun visible-light irradiation. Thus, La2O3–CoO–g-C3N4 nanocomposite was found to be a prospective material for harnessing solar energy.

Preparation, Analysis and Antibacterial Evaluation of Some New 1,3,5-Trisubstituted Pyrazole Derivatives

The goal of this study was to develop, synthesise, and characterise a novel 1,3,5-trisubstituted-2-pyrazoline derivative, as well as test its antibacterial activity. The reaction of chalcone derivatives with succinic hydrazide in the presence of pyridine yielded the 1,3,5-tri-substituted-2-pyrazolines derivatives. The IR, 1HNMR, and mass spectral analyses were used to characterise a total of 20 substances. Antibacterial activity of the compounds was tested on five Gm+Ve bacterial strains (Staphylococcus aureus, S. Faecalis, Bacillus Substilis, P. Vulgaris, and B. Pumilus) and two Gm-Ve bacterial strains (Staphylococcus aureus, S. Faecalis, Bacillus Substilis, P. Vulgaris, and B. Pumilus) and two Gm-Ve i.e. Escherichia Coli, Klebsiella Penumoniae in two different concentration i.e. 50 and 100 µg/ml by Agar-diffusion method using Cup-plate method. Standard antimicrobial drugs were Norfloxacin and Ciprofloxacin. The antibacterial activity of substances against Gm+Ve bacterial strains (Staphylococcus Aureus, Staphylococcus Faecalis, Bacillus Substilis, Pseudomonas Vulgaris, and B. Pumilus) suggested the following order of action: BR-3 >BR-2>BR-1>CL-4>BR-4>CL-3> CL-2>CL-5>CL-6>ME-3>ME-2>ME-4>ME-5>ME-6>ME-7>CL-7>CL-8>CL-1>ME-8>ME-1>ME-8>ME-1>ME-8>ME-1>ME-8>ME-1>ME-8>ME-1>ME-8>ME-1>ME-8>ME-1>ME-8>ME-1>ME-8>ME-1>ME-8>ME The chemicals of the BR-1 to BR-4 series have the most action. ME-8, CL-8, CL-7, CL-1, ME-5, ME-6, and ME-1 have light activity, whereas CL-2, CL-5, ME-4, CL-6, ME-3, ME-2, and ME-7 have moderate activity. The compounds BR-3, BR-2, BR-1, CL-4, BR-4, and CL-3 have been shown to have excellent action. The result data of antibacterial activity suggested that Cl, Br, F, and Nitro substitution at third and Fifth position may enhance the antbacterial activity of the compounds but the methyl and methoxy substitution may resulted in reduction of the activity.

Luminescence of Baikal water as a dynamic background of the Baikal-GVD Neutrino Telescope

The Baikal-GVD is a neutrino telescope situated in the deepest freshwater lake in the world — Lake Baikal. The design of the Baikal-GVD trigger system allows also to study the ambient light of the lake. The analysis of the optical light activity of Baikal water, particularly, time and spatial variations of the luminescence activity for data collected in years 2018, 2019, and 2020 is presented. For the first time we observed highly luminescent layer moving upwards with maximal speed of 28 m/day in January 2021.

Three-Dimensional Graphene Network and UiO-66 Based Composite Photocatalysts for High Visible-Light Activity

Three-dimensional graphene network (3DGN) and UiO-66 co-modified composite photocatalysts are prepared to decompose dye in solution. The roles of UiO-66 and 3DGN are studied based on the adsorption capacity, visible-light activity, lifetime of photo-induce electrons and electron paramagnetic resonance curves. The rates of degradation of Rhodamine-B are [Formula: see text][Formula: see text]min[Formula: see text] and [Formula: see text][Formula: see text]min[Formula: see text] under UV- and visible-light irradiation. The major function of UiO-66 is increasing the Brunner–Emmet–Teller surface area and adsorption capacity significantly, while the effect of 3DGN is playing as an electron tank and sensitizer. Moreover, the influence of mass fraction of UiO-66 on the resulting photocatalytic performances is revealed (5[Formula: see text]wt.% is found the optimized value), and the synergy is also discussed. Finally, the photocatalytic mechanisms of the resulting photocatalysts both under the UV- and visible-light irradiation are proposed.

Assessment of Radiation dose from Inhalation of Outdoor Dust Containing Natural Radionuclides

The 238U, 232Th and 40K concentrations were estimated in the size-fractionated urban surface deposited sediments in Ekaterinburg, Russia. The average concentrations of 238U, 232Th and 40K in dust fraction (0.002–0.05 mm) are 48 ± 7, 28 ± 1 and 510 ± 20 Bq/kg, respectively. The effective dose is estimated depending on the suggested daily scenarios of different exercises which can be assigned to light, moderate and vigorous activity. The results show that the total effective dose received during 20 years by an adult with the light activity is 5.6 μSv under exposure to air dust concentration 1 × 10−4 g/m3, which is typical for the city of Ekaterinburg. Although for the moderate and vigorous activities the total effective dose is 9.9 μSv and 48.8 μSv, respectively, during 20 years at air dust concentration equal to the diurnal Maximum Permissible Limit (1.5 × 10−4 g/m3). Thus, the effective doses due to natural radionuclides in the dust fraction are relatively low in comparison ICRP reference level.

Joint associations between objectively measured physical activity volume and intensity with body fatness: the Fenland study

Background/Objectives Physical activity energy expenditure (PAEE) represents the total volume of all physical activity. This can be accumulated as different underlying intensity profiles. Although volume and intensity have been studied in isolation, less is known about their joint association with health. We examined this association with body fatness in a population-based sample of middle-aged British adults. Methods In total, 6148 women and 5320 men from the Fenland study with objectively measured physical activity from individually calibrated combined heart rate and movement sensing and DXA-derived body fat percentage (BF%) were included in the analyses. We used linear and compositional isocaloric substitution analysis to examine associations of PAEE and its intensity composition with body fatness. Sex-stratified models were adjusted for socio-economic and dietary covariates. Results PAEE was inversely associated with body fatness in women (beta = −0.16 (95% CI: −0.17; −0.15) BF% per kJ day−1 kg−1) and men (beta = −0.09 (95% CI: −0.10; −0.08) BF% per kJ day−1 kg−1). Intensity composition was significantly associated with body fatness, beyond that of PAEE; the reallocation of energy to vigorous physical activity (>6 METs) from other intensities was associated with less body fatness, whereas light activity (1.5–3 METs) was positively associated. However, light activity was the main driver of overall PAEE volume, and the relative importance of intensity was marginal compared to that of volume; the difference between PAEE in tertile 1 and 2 in women was associated with 3 percentage-point lower BF%. Higher vigorous physical activity in the same group to the maximum observed value was associated with 1 percentage-point lower BF%. Conclusions In this large, population-based cohort study with objective measures, PAEE was inversely associated with body fatness. Beyond the PAEE association, greater levels of intense activity were also associated with lower body fatness. This contribution was marginal relative to PAEE. These findings support current guidelines for physical activity which emphasise that any movement is beneficial, rather than specific activity intensity or duration targets.

Association of physical activity intensity and bout length with mortality: An observational study of 79,503 UK Biobank participants

Background Spending more time active (and less sedentary) is associated with health benefits such as improved cardiovascular health and lower risk of all-cause mortality. It is unclear whether these associations differ depending on whether time spent sedentary or in moderate-vigorous physical activity (MVPA) is accumulated in long or short bouts. In this study, we used a novel method that accounts for substitution (i.e., more time in MVPA means less time sleeping, in light activity or sedentary) to examine whether length of sedentary and MVPA bouts associates with all-cause mortality. Methods and findings We used data on 79,503 adult participants from the population-based UK Biobank cohort, which recruited participants between 2006 and 2010 (mean age at accelerometer wear 62.1 years [SD = 7.9], 54.5% women; mean length of follow-up 5.1 years [SD = 0.73]). We derived (1) the total time participants spent in activity categories—sleep, sedentary, light activity, and MVPA—on average per day; (2) time spent in sedentary bouts of short (1 to 15 minutes), medium (16 to 40 minutes), and long (41+ minutes) duration; and (3) MVPA bouts of very short (1 to 9 minutes), short (10 to 15 minutes), medium (16 to 40 minutes), and long (41+ minutes) duration. We used Cox proportion hazards regression to estimate the association of spending 10 minutes more average daily time in one activity or bout length category, coupled with 10 minutes less time in another, with all-cause mortality. Those spending more time in MVPA had lower mortality risk, irrespective of whether this replaced time spent sleeping, sedentary, or in light activity, and these associations were of similar magnitude (e.g., hazard ratio [HR] 0.96 [95% CI: 0.94, 0.97; P < 0.001] per 10 minutes more MVPA, coupled with 10 minutes less light activity per day). Those spending more time sedentary had higher mortality risk if this replaced light activity (HR 1.02 [95% CI: 1.01, 1.02; P < 0.001] per 10 minutes more sedentary time, with 10 minutes less light activity per day) and an even higher risk if this replaced MVPA (HR 1.06 [95% CI: 1.05, 1.08; P < 0.001] per 10 minutes more sedentary time, with 10 minutes less MVPA per day). We found little evidence that mortality risk differed depending on the length of sedentary or MVPA bouts. Key limitations of our study are potential residual confounding, the limited length of follow-up, and use of a select sample of the United Kingdom population. Conclusions We have shown that time spent in MVPA was associated with lower mortality, irrespective of whether it replaced time spent sleeping, sedentary, or in light activity. Time spent sedentary was associated with higher mortality risk, particularly if it replaced MVPA. This emphasises the specific importance of MVPA. Our findings suggest that the impact of MVPA does not differ depending on whether it is obtained from several short bouts or fewer longer bouts, supporting the recent removal of the requirement that MVPA should be accumulated in bouts of 10 minutes or more from the UK and the United States policy. Further studies are needed to investigate causality and explore health outcomes beyond mortality.