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The skyrocketing single-plastic demand during the coronavirus disease 2019 (COVID-19) pandemic proved the limitation of top-down environmental policies in accomplishing sustainable consumption and waste management. Nevertheless, 'smart consumers' can make smart choices for sustainable development. However, a review of the South Korean environmental education curriculum reveals that the current structure heavily leans towards the elementary level and does not enlighten the public on 'what' and 'how' to live sustainably. This study uses a quick survey to suggest that the effectiveness of environmental education may be enhanced if: (1) guidance on how to live with the natural environment in harmony for collective cooperation towards resilient and sustainable community building is incorporated with a clear purpose, (2) environment-friendly culture-building activities are enforced to institutionalise a new paradigm of sustainability to replace today's consumerism, and (3) contents are updated regularly to include Earth and environmental science knowledge in the state of art. [ABSTRACT FROM AUTHOR]

The epidemiological characteristics of women living with human immunodeficiency virus (HIV) infection have gained little attention as the numbers are small compared with men living with HIV in the Republic of Korea. However, these data are important to achieve effective HIV infection control and to consider the influence of socioeconomic status on HIV transmission. This study utilized the claims database of the Korean National Health Insurance system to analyze women with a newly diagnosed HIV infection during the period 2009–2016. Adherence to antiretroviral agents was calculated using the medication possession ratio. Among 677 women with a newly diagnosed HIV infection, 219 (32.4%) were over 50 years of age; 291 (43.0%) were identified as having acquired immune deficiency syndrome (AIDS). A total of 99 women (14.6%) were National Medical Aid beneficiaries. Optimal medical adherence >95% was found in 62.2% of subjects. Teenage years (odds ratio(OR) 14.9, 95% confidence interval (95CI) 4.9-44.8), AIDS (OR 1.7, 95CI 1.2-2.3), and low economic status requiring National Medical Aid (OR 3.0, 95CI 2.0-4.6) were associated to adherence. Diagnosis prior to 2012 was also associated with poor adherence. In women, particularly young patients with low economic status, extra attention is required to enhance adherence to prescribed medication. [ABSTRACT FROM AUTHOR]

Condomless sex is not totally discouraged after achieving undetectable human immunodeficiency virus (HIV) load, but the prevalence of sexually transmitted diseases (STDs) in the group is unknown. This study was retrospective in nature, using the claims database of the National Health Insurance system from 2008 to 2016. The clinical characteristics of people living with HIV with or without syphilis coinfection were analyzed. People with HIV and syphilis coinfection were divided into two groups according to antiretroviral therapy adherence, as optimal and suboptimal adherence groups by a medication possession ratio of 95%. Of the 9393 people living with HIV, 4536 (48.3%) were diagnosed with syphilis coinfection. Optimal adherence was associated with syphilis coinfection (odds ratio [OR] 1.18; 95% confidence interval [95CI] 1.08–1.30; p =.001). This suggests that unsafe sex occurs regardless of medication adherence. Being male, bacterial/protozoa STDs, and genital herpes virus infection were also risk factors for HIV-syphilis coinfection. Although HIV is unlikely to be transmittable when viral load is controlled, consistent use of condoms is necessary to prevent infection with syphilis. [ABSTRACT FROM AUTHOR]

Supramolecular complexation of two bio-thiols, homocysteine (Hcys) and cysteine (Cys), by cucurbit[7]uril (CB[7]) has been fully investigated by 1H NMR spectroscopy, mass spectrometry, isothermal titration calorimetry, and the results were further verified with computational investigations. NMR titration experimental results obviously indicate that the binding stoichiometry of CB[7] to Hcys is 1:1 and to Cys is 1:2 in aqueous solution. The binding constants and thermodynamic parameters associated with the complexation between CB[7] and the bio-thiols were determined by isothermal titration calorimetry. The energy-minimized structures of the supramolecular complexes of CB[7] with Hcys and Cys were determined and provide good agreement with the experimental results. The CB[7] cavity is sufficient to include the two Cys, but is unable to accommodate two Hcys due to steric hindrance. The differing binding abilities of Hcys and Cys in aqueous solution towards CB[7] host may lead to discriminate them. [ABSTRACT FROM AUTHOR]

Background: The histologic responses to varied parameters of 1,927-nm fractional thulium fiber laser treatment have not yet been sufficiently elucidated.Objective: This study sought to evaluate histologic changes immediately after 1,927-nm fractional thulium fiber laser session at various parameters.Methods: The dorsal skin of Yucatan mini-pig was treated with 1,927-nm fractional thulium fiber laser at varied parameters, with or without skin drying. The immediate histologic changes were evaluated to determine the effects of varying laser parameters on the width and the depth of treated zones.Results: The increase in the level of pulse energy widened the area of epidermal changes in the low power level, but increased the dermal penetration depth in the high power level. As the pulse energy level increased, the increase in the power level under the given pulse energy level more evidently made dermal penetration deeper and the treatment area smaller. Skin drying did not show significant effects on epidermal changes, but evidently increased the depth of dermal denaturation under both high and low levels of pulse energy.Conclusion: These results may provide important information to establish treatment parameters of the 1,927-nm fractional thulium fiber laser for various skin conditions. [ABSTRACT FROM PUBLISHER]

We examined the current groundwater (used for drinking) quality in Pakistan after implementation of Millennium Development Goals, including contaminants, their sources, and relevant health impacts. The drinking water quality parameters of most of the reported results exceeded the guidelines suggested by the World Health Organization (WHO) and National Environmental Quality Standards (NEQS). Natural sources of groundwater contamination have been activated due to anthropogenic activities like mining, and open dumping of industrial and domestic wastes which lead to poor groundwater quality. Globally, 780 million people, and 100 million people in Pakistan are exposed to unsafe water sources. Therefore, this review demonstrates the potential needs to achieve the safe drinking water goal of the Agenda 2030. The development of a proper monitoring network, installation of treatment plants, and implementation of legislations are recommended in this review. [ABSTRACT FROM AUTHOR]

In this study, we investigated a series of metal-free benzotriazole-based organic dyes. The geometries, electronic properties, light harvesting efficiency, and electronic absorption spectra of these dyes were studied using the density functional theory and time-dependent density functional theory. The optimised geometries indicate that these dyes are non-planar and thereby effectively inhibit close intermolecular π–π aggregation. The band gap of these dyes ensures a positive effect on the process of electron injection and dye regeneration. The band gap trend corroborates well with the predicted spectra data. Our theoretical calculations reveal that the designed metal-free organic dyes can be used as potential sensitisers for solar cells compared to the best known organic sensitiser (Y123) to date. [ABSTRACT FROM AUTHOR]

Underground air has been gaining popularity for space heating and cooling on Jeju volcanic island, Korea, because there are many geological and societal limitations in the application of conventional ground source heat pump systems. The underground air temperature on the Jeju Island is very stable, at 15°C–19°C (median 17°C), throughout the year, while the ambient air temperature varies widely. In addition, vesicular basalts widespread in the island facilitate the extraction of underground air. As of 2007, there were 63 underground air facilities used, which were mostly greenhouses for growing fruits, vegetables, flowers, and ornamental shrubs. Practical operations and agricultural studies have revealed that the supply of underground air to greenhouses growing plants saved energy costs and enhanced crop production due to the high CO2 content in the underground air. Despite these advantageous features, there are still some problems that need to be resolved including public grievance relating to potential groundwater contamination due to the drilling of boreholes and lack of technical experiences in optimal system design. Regulations have not been tailored to the use of underground air systems, which is still not officially acknowledged as a renewable energy source and these factors will need to be resolved prior to the sustainable use of underground air. [ABSTRACT FROM AUTHOR]

Soil and groundwater at a rail rolling stock workshop in a metropolitan city were contaminated with heavy metals including Pb, Cu and Cd. Prior to remedial design, a variety of field and laboratory investigations were conducted to characterize hydrogeologic conditions and to examine levels and extents of the contamination. The hydrogeology of the studied site near the Han River is comprised of reclamation soil, alluvial deposit, weathered layer and soft rock. The alluvial deposit consists of sand, clay and silt, sandy gravel and its spatial distribution is very heterogeneous. Most groundwater occurs in the sandy gravel layer and groundwater within the site generally flows into two directions, north and west. Mean hydraulic gradients were 0.082-0.0129 and hydraulic conductivities of the main aquifer range between 5.42 × 10- 2 and 2.18 × 10- 6 cm/sec. Average linear velocity of groundwater was calculated as 15-24 m/year. The groundwater levels were mostly affected by atmospheric pressure change, which reflected confined characteristics of the aquifer system. High EC and low DO indicated anthropogenic contamination of the site. The Pb and Cu contamination of soil exceeding the Korean soil standards were mainly observed at locomotive inspection, rest train wash and scrap iron dump areas. Substantial contamination of groundwater with Cd was also detected at different location. [ABSTRACT FROM AUTHOR]

As computational methods have been drastically developed in parallel with the advancement of the computer and electronics industry, computational chemistry now shows a wide number of applications for many complicated supramolecular systems which were not feasible to carry out in the past. In many supramolecular systems, their structures and functions have been successfully understood with the aid of computational approaches. In this mini-review, several computational approaches will be introduced that have been applied to molecular recognition, self-assembly, photo-induced electron transfer, and chemical structures and reactions on surfaces as well as basic computational methods. [ABSTRACT FROM AUTHOR]

The feasibility of soil vapor extraction and bioventing technologies was examined for a petroleum hydrocarbon-contaminated site. The test site was highly contaminated with toluene, ethylbenzene, and xylene, due to leakage from petroleum storage tanks. Three respiration tests demonstrated that the test site conditions were appropriate for application of air-based remediation technologies. The oxygen consumption rates ranged from 4.32 to 7.68 %-O 2 /day and biodegradation rates ranged from 2.72 to 4.84 mg/kg-day in respiration tests. In a 120-day soil vapor extraction pilot test, high initial mass removals (with tailing effects) were observed. As expected for the soil vapor extraction, the volatilization rate was much higher than the biodegradation rate. In a bioventing trial, the biodegradation effect was predominant, but a tailing effect was not observed. From this study, the suggested sequence of remediation is to construct an integrated system of soil vapor extraction and bioventing and initially operate the soil vapor extraction system until the volatilization rate becomes smaller than the biodegradation rate. After that, the system needs to be changed over to a bioventing mode. Field demonstration supports the feasibility of the proposed integrated system. [ABSTRACT FROM AUTHOR]