Enhanced Oxidation of Phenol by Copper-catalyzed Fenton-like Reaction in the Presence of Bicarbonate

In this study, the copper-catalyzed Fenton-like reaction in the presence of bicarbonate (i.e., the Cu(II)/HCO3-/H2O2 system) was examined for the phenol degradation. The rate of phenol degradation by the copper-catalyzed Fenton-like reaction ([Cu(II)]0 = 0.1 mM, [H2O2]0 = 10 mM, pH = 10) was accelerated by 17-fold in the presence of 50 mM HCO3-. The rate of phenol degradation by the Cu(II)/HCO3-/H2O2 system increased with increasing doses of Cu(II) and HCO3-, but showed an optimal value for the H2O2 dose and pH at 5 mM and 10, respectively. The Cu(II)/HCO3-/H2O2 system was selective in degrading phenolic compounds; benzoic acid was resistant to degradation. Cu(III) species (likely complexed forms with carbonate) are believed to be the reactive oxidants responsible for the phenol degradation by the Cu(II)/HCO3-/H2O2 system. Meanwhile, aerating CO2 gas successfully accelerated the phenol degradation by the copper-catalyzed Fenton-like reaction, implying that CO2 aeration can be a practical option to supply bicarbonate when implementing the Cu(II)/HCO3-/H2O2 system

Accuracy of analytical approaches to thermal response test interpretation

Thermal conductivity obtained via thermal response test (TRT) is one of the essential parameters for the design of shallow geothermal systems, especially a borehole heat exchanger (BHE). During TRT analysis, several factors (e.g., start time of analysis and test duration) could influence the estimated thermal conductivity. In addition, the influence of the factors may be different depending on the characteristics of the borehole and ground. This study investigated the effects of the start time and test duration through numerically generated TRT data under a diversity of environment and BHE information such as the thermal conductivity of grouting and ground. The generated numerical data were analyzed with three analytical approaches having different assumptions about the heat source to interpret the sensitivity of factors in the TRT analysis. By conducting the analytical sensitivity analysis, the importance of determining the appropriate start time and test duration could be emphasized when designing the test

Effect of FIXed-dose combination of ARb and statin on adherence and risk factor control: The randomized FIXAR study

Background: The efficacy of fixed-dose combinations (FDCs) in improving adherence and risk factor control for cardiovascular disease has not been reported consistently. Here, we compared adherence and efficacy between an olmesartan/rosuvastatin FDC and the usual regimen. Methods: In this 6-month, open-label, randomized, active-control study, we screened 154 patients; of these, 150 were randomly assigned to receive either olmesartan/rosuvastatin FDC or the usual regimen with separate angiotensin receptor blockers and statins. In total, 135 patients completed the study (median age: 68 years; male: 68.9%). The primary outcome was patients’ adherence; the secondary outcomes were changes in blood pressure (BP) and lipid parameters. Results: During follow-up, adherence in both groups was high and similar between the groups (98.9% and 98.3% in the FDC and usual regimen groups, respectively, p = 0.328). Changes in systolic (–8 and –5 mmHg, respectively, p = 0.084) and diastolic BP (–5 and –2 mmHg, p = 0.092) did not differ significantly, although they were numerically greater in the FDC group. Changes in low-density lipoprotein cholesterol (LDL-C) were greater in the FDC group (–13 and –4 mg/dL, respectively, p = 0.019), whereas changes in other lipid parameters were similar between the groups. The test drugs were well tolerated, showing no difference in safety between the groups. Conclusions: Patients’ adherence was excellent and similar in the groups, whereas the reduction in the LDL-C level was greater in the FDC group. We provide comprehensive information on the adherence and efficacy of an FDC compared to the usual regimen in Korean patients with high cardiovascular risk

Photometric Selection of Unobscured QSOs in the Ecliptic Poles: KMTNet in the South Field and Pan-STARRS in the North Field

We search for quasi-stellar objects (QSOs) in a wide area of the south ecliptic pole (SEP) field, which has been and will continue to be intensively explored through various space missions. For this purpose, we obtain deep broadband optical images of the SEP field covering an area of $\sim$$14.5\times14.5$ deg$^2$ with the Korea Microlensing Telescope Network. The 5$\sigma$ detection limits for point sources in the $BVRI$ bands are estimated to be $\sim$22.59, 22.60, 22.98, and 21.85 mag, respectively. Utilizing data from Wide-field Infrared Survey Explorer, unobscured QSO candidates are selected among the optically point-like sources using the mid-infrared (MIR) and optical-MIR colors. To further refine our selection and eliminate any contamination not adequately removed by the color-based selection, we perform the spectral energy distribution fitting with archival photometric data ranging from optical to MIR. As a result, we identify a total of 2,383 unobscured QSO candidates in the SEP field. We also apply a similar method to the north ecliptic pole field using the Pan-STARRS data and obtain a similar result of identifying 2,427 candidates. The differential number count per area of our QSO candidates is in good agreement with those measured from spectroscopically confirmed ones in other fields. Finally, we compare the results with the literature and discuss how this work will be implicated in future studies, especially with the upcoming space missions.Comment: 14 pages, 9 figures, accepted for publication in ApJ

Photobiocidal-triboelectric nanolayer coating of photosensitizer/silica-alumina for reusable and visible-light-driven antibacterial/antiviral air filters

Outbreaks of airborne pathogens pose a major threat to public health. Here we present a single-step nanocoating process to endow commercial face mask filters with photobiocidal activity, triboelectric filtration capability, and washability. These functions were successfully achieved with a composite nanolayer of silica-alumina (Si-Al) sol-gel, crystal violet (CV) photosensitizer, and hydrophobic electronegative molecules of 1H, 1H, 2H, 2H-perfluorooctyltriethoxysilane (PFOTES). The transparent Si-Al matrix strongly immobilized the photosensitizer molecules while dispersing them spatially, thus suppressing self-quenching. During nanolayer formation, PFOTES was anisotropically rearranged on the Si-Al matrix, promoting moisture resistance and triboelectric charging of the Si-Al/PFOTES-CV (SAPC)-coated filter. The SAPC nanolayer stabilized the photoexcited state of the photosensitizer and promoted redox reaction. Compared to pure-photosensitizer-coated filters, the SAPC filter showed substantially higher photobiocidal efficiency (∼99.99 % for bacteria and a virus) and photodurability (∼83 % reduction in bactericidal efficiency for the pure-photosensitizer filter but ∼0.34 % for the SAPC filter after 72 h of light irradiation). Moreover, after five washes with detergent, the SAPC filter maintained its photobiocidal and filtration performance, proving its reusability potential. Therefore, this SAPC nanolayer coating provides a practical strategy for manufacturing an antimicrobial and reusable mask filter for use during the ongoing COVID-19 pandemic

Comparison between Wild and Hatchery Populations of Korean Pen Shell (Atrina pectinata) Using Microsatellite DNA Markers

Pen shell (Atrina pectinata) is a popular food source with a high commercial value in a number of Asian Pacific areas. The natural A. pectinata population has been declining continuously over the past several decades. Microsatellite DNA markers are a useful DNA-based tool for monitoring the genetic variation of pen shell populations. In this study, 20 polymorphic microsatellite (MS) DNA markers were identified from a partial genomic pen shell DNA library enriched in CA repeats, and used to compare allelic variation between wild and hatchery pen shell populations in Korea. A total of 438 alleles were detected at the 20 MS loci in the two populations. All loci were easily amplified and demonstrated allelic variability, with the number of alleles ranging from 5 to 35 in the wild population and from 5 to 22 in the farmed population. The average observed and expected heterozygosities were 0.69 and 0.82, respectively, in the hatchery samples and 0.69 and 0.83, respectively, in the wild samples. Statistical analysis of fixation index (FST) and analysis of molecular variance (AMOVA) showed minor, but significant, genetic differences between the wild and hatchery populations (FST = 0.0106, CI95% = 0.003–0.017). These microsatellite loci may be valuable for future aquaculture and population genetic studies for developing conservation and management plans. Further studies with additional pen shell samples are needed to conclusively determine the genetic diversity between the wild and hatchery populations

Multi-strain probiotics alleviate loperamide-induced constipation by adjusting the microbiome, serotonin, and short-chain fatty acids in rats

Constipation is one of the most common gastrointestinal (GI) disorders worldwide. The use of probiotics to improve constipation is well known. In this study, the effect on loperamide-induced constipation by intragastric administration of probiotics Consti-Biome mixed with SynBalance® SmilinGut (Lactobacillus plantarum PBS067, Lactobacillus rhamnosus LRH020, Bifidobacterium animalis subsp. lactis BL050; Roelmi HPC), L. plantarum UALp-05 (Chr. Hansen), Lactobacillus acidophilus DDS-1 (Chr. Hansen), and Streptococcus thermophilus CKDB027 (Chong Kun Dang Bio) to rats was evaluated. To induce constipation, 5 mg/kg loperamide was intraperitoneally administered twice a day for 7 days to all groups except the normal control group. After inducing constipation, Dulcolax-S tablets and multi-strain probiotics Consti-Biome were orally administered once a day for 14 days. The probiotics were administered 0.5 mL at concentrations of 2 × 108 CFU/mL (G1), 2 × 109 CFU/mL (G2), and 2 × 1010 CFU/mL (G3). Compared to the loperamide administration group (LOP), the multi-strain probiotics not only significantly increased the number of fecal pellets but also improved the GI transit rate. The mRNA expression levels of serotonin- and mucin-related genes in the colons that were treated with the probiotics were also significantly increased compared to levels in the LOP group. In addition, an increase in serotonin was observed in the colon. The cecum metabolites showed a different pattern between the probiotics-treated groups and the LOP group, and an increase in short-chain fatty acids was observed in the probiotic-treated groups. The abundances of the phylum Verrucomicrobia, the family Erysipelotrichaceae and the genus Akkermansia were increased in fecal samples of the probiotic-treated groups. Therefore, the multi-strain probiotics used in this experiment were thought to help alleviate LOP-induced constipation by altering the levels of short-chain fatty acids, serotonin, and mucin through improvement in the intestinal microflora