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1.
J Hazard Mater ; 474: 134852, 2024 Aug 05.
Article in English | MEDLINE | ID: mdl-38852250

ABSTRACT

Pharmaceuticals, personal care products (PPCPs), and endocrine-disrupting compounds (EDCs) have seen a recent sustained increase in usage, leading to increasing discharge and accumulation in wastewater. Conventional water treatment and disinfection processes are somewhat limited in effectively addressing this micropollutant issue. Ultrasonication (US), which serves as an advanced oxidation process, is based on the principle of ultrasound irradiation, exposing water to high-frequency waves, inducing thermal decomposition of H2O while using the produced radicals to oxidize and break down dissolved contaminants. This review evaluates research over the past five years on US-based technologies for the effective degradation of EDCs and PPCPs in water and assesses various factors that can influence the removal rate: solution pH, temperature of water, presence of background common ions, natural organic matter, species that serve as promoters and scavengers, and variations in US conditions (e.g., frequency, power density, and reaction type). This review also discusses various types of carbon/non-carbon catalysts, O3 and ultraviolet processes that can further enhance the degradation efficiency of EDCs and PPCPs in combination with US processes. Furthermore, numerous types of EDCs and PPCPs and recent research trends for these organic contaminants are considered.


Subject(s)
Cosmetics , Endocrine Disruptors , Water Pollutants, Chemical , Water Purification , Endocrine Disruptors/chemistry , Water Pollutants, Chemical/chemistry , Water Pollutants, Chemical/radiation effects , Pharmaceutical Preparations/chemistry , Cosmetics/chemistry , Water Purification/methods , Ultrasonics , Ultrasonic Waves
2.
J Environ Manage ; 363: 121437, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38852419

ABSTRACT

Membrane-based water treatment has emerged as a promising solution to address global water challenges. Graphene oxide (GO) has been successfully employed in membrane filtration processes owing to its reversible properties, large-scale production potential, layer-to-layer stacking, great oxygen-based functional groups, and unique physicochemical characteristics, including the creation of nano-channels. This review evaluates the separation performance of various GO-based membranes, manufactured by coating or interfacial polymerization with different support layers such as polymer, metal, and ceramic, for endocrine-disrupting compounds (EDCs) and pharmaceutically active compounds (PhACs). In most studies, the addition of GO significantly improved the removal efficiency, flux, porosity, hydrophilicity, stability, mechanical strength, and antifouling performance compared to pristine membranes. The key mechanisms involved in contaminant removal included size exclusion, electrostatic exclusion, and adsorption. These mechanisms could be ascribed to the physicochemical properties of compounds, such as molecular size and shape, hydrophilicity, and charge state. Therefore, understanding the removal mechanisms based on compound characteristics and appropriately adjusting the operational conditions are crucial keys to membrane separation. Future research directions should explore the characteristics of the combination of GO derivatives with various support layers, by tailoring diverse operating conditions and compounds for effective removal of EDCs and PhACs. This is expected to accelerate the development of surface modification strategies for enhanced contaminant removal.


Subject(s)
Endocrine Disruptors , Graphite , Membranes, Artificial , Water Pollutants, Chemical , Water Purification , Graphite/chemistry , Endocrine Disruptors/chemistry , Water Purification/methods , Water Pollutants, Chemical/chemistry , Filtration , Adsorption , Water/chemistry
3.
Chemosphere ; 356: 141941, 2024 May.
Article in English | MEDLINE | ID: mdl-38588897

ABSTRACT

Bisphenol A (BPA), a widely recognized endocrine disrupting compound, has been discovered in drinking water sources/finished water and domestic wastewater influent/effluent. Numerous studies have shown photocatalytic and electrocatalytic oxidation to be very effective for the removal of BPA, particularly in the addition of graphene/graphene oxide (GO)-based nanocatalysts. Nevertheless, the photocatalytic and electrocatalytic degradation of BPA in aqueous solutions has not been reviewed. Therefore, this review gives a comprehensive understanding of BPA degradation during photo-/electro-catalytic activity in the presence of graphene/GO-based nanocatalysts. Herein, this review evaluated the main photo-/electro-catalytic degradation mechanisms and pathways for BPA removal under various water quality/chemistry conditions (pH, background ions, natural organic matter, promotors, and scavengers), the physicochemical characteristics of various graphene/GO-based nanocatalysts, and various operating conditions (voltage and current). Additionally, the reusability/stability of graphene/GO-based nanocatalysts, hybrid systems combined with ozone/ultrasonic/Fenton oxidation, and prospective research areas are briefly described.


Subject(s)
Benzhydryl Compounds , Graphite , Phenols , Water Pollutants, Chemical , Graphite/chemistry , Benzhydryl Compounds/chemistry , Catalysis , Phenols/chemistry , Water Pollutants, Chemical/chemistry , Oxidation-Reduction , Water Purification/methods , Endocrine Disruptors/chemistry , Photochemical Processes , Electrochemical Techniques/methods
4.
J Hazard Mater ; 469: 134072, 2024 May 05.
Article in English | MEDLINE | ID: mdl-38522201

ABSTRACT

Acid leaching has been widely applied to treat contaminated soil, however, it contains several inorganic pollutants. The decommissioning of nuclear power plants introduces radioactive and soluble U(VI), a substance posing chemical toxicity to humans. Our investigation sought to ascertain the efficacy of hexagonal boron nitride (h-BN), an highly efficient adsorbent, in treating U(VI) in wastewater. The adsorption equilibrium of U(VI) by h-BN reached saturation within a mere 2 h. The adsorption of U(VI) by h-BN appears to be facilitated through electrostatic attraction, as evidenced by the observed impact of pH variations, acidic agents (i.e., HCl or H2SO4), and the presence of background ions on the adsorption performance. A reusability test demonstrated the successful completion of five cycles of adsorption/desorption, relying on the surface characteristics of h-BN as influenced by solution pH. Based on the experimental variables of initial U(VI) concentration, exposure time, temperature, pH, and the presence of background ions/organic matter, a feature importance analysis using random forest (RF) was carried out to evaluate the correlation between performances and conditions. To the best of our knowledge, this study is the first attempt to conduct the adsorption of U(VI) generated from real contaminated soil by h-BN, followed by interpretation of the correlation between performance and conditions using RF. Lastly, a. plausible adsorption mechanism between U(VI) and h-BN was explained based on the experimental results, characterizations, and a. comparison with previous adsorption studies on the removal of heavy metals by h-BN.

5.
Chemosphere ; 354: 141676, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38462187

ABSTRACT

The existence of pollutants, such as toxic organic dye chemicals, in water and wastewater raises concerns as they are inadequately eliminated through conventional water and wastewater treatment methods, including physicochemical and biological processes. Ultrasonic treatment has emerged as an advanced treatment process that has been widely applied to the decomposition of recalcitrant organic contaminants. Ultrasonic treatment has several advantages, including easy operation, sustainability, non-secondary pollutant production, and saving energy. This review examines the elimination of dye chemicals and categorizes them into cationic and anionic dyes based on the existing literature. The objectives include (i) analyzing the primary factors (water quality and ultrasonic conditions) that influence the sonodegradation of dye chemicals and their byproducts during ultrasonication, (ii) assessing the impact of the different sonocatalysts and combined systems (with ozone and ultraviolet) on sonodegradation, and (iii) exploring the characteristics-based removal mechanisms of dyes. In addition, this review proposes areas for future research on ultrasonic treatment of dye chemicals in water and wastewater.


Subject(s)
Environmental Pollutants , Ozone , Water Pollutants, Chemical , Water Purification , Wastewater , Coloring Agents/chemistry , Ultrasonics , Water Pollutants, Chemical/chemistry , Water Purification/methods
6.
Chemosphere ; 349: 140800, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38040264

ABSTRACT

Boron nitride (BN) coupled with various conventional and advanced photocatalysts has been demonstrated to exhibit extraordinary activity for photocatalytic degradation because of its unique properties, including a high surface area, constant wide-bandgap semiconducting property, high thermal-oxidation resistance, good hydrogen-adsorption performance, and high chemical/mechanical stability. However, only limited reviews have discussed the application of BN or BN-based nanomaterials as innovative photocatalysts, and it does not cover the recent results and the developments on the application of BN-based nanomaterials for water purification. Herein, we present a complete review of the present findings on the photocatalytic degradation of different contaminants by various BN-based nanomaterials. This review includes the following: (i) the degradation behavior of different BN-based photocatalysts for various contaminants, such as selected dye compounds, pharmaceuticals, personal care products, pesticides, and inorganics; (ii) the stability/reusability of BN-based photocatalysts; and (iii) brief discussion for research areas/future studies on BN-based photocatalysts.


Subject(s)
Nanostructures , Boron Compounds , Water , Adsorption
7.
ACS Appl Mater Interfaces ; 15(50): 58761-58769, 2023 Dec 20.
Article in English | MEDLINE | ID: mdl-38084724

ABSTRACT

Regular arrays of colloidal particles can produce striking structural colors without the need for any chemical pigments. Regular arrays of colloidal particles can be processed into microparticles via emulsion templates for use as structural colorants. Photonic microparticles, however, suffer from intense incoherent scattering and lack of suspension stability. We propose a microfluidic technique to generate hydrogel-shelled photonic microspheres that display enhanced color saturation and suspension stability. We created these microspheres using oil-in-water-in-oil (O/W/O) double-emulsion droplets with well-defined dimensions with a capillary microfluidic device. The inner oil droplet contains silica particles in a photocurable monomer, while the middle water droplet carries the hydrogel precursor. Within the inner oil droplet, silica particles arrange into crystalline arrays due to solvation-layer-induced interparticle repulsion. UV irradiation solidifies the inner photonic core and the outer hydrogel shell. The hydrogel shell reduces white scattering and enhances the suspension stability in water. Notably, the hydrogel precursor in the water droplet aids in maintaining the solvation layer, resulting in enhanced crystallinity and richer colors compared with microspheres from O/W single-emulsion droplets. These hydrogel-encased photonic microspheres show promise as structural colorants in water-based inks and polymer composites.

8.
Sci Total Environ ; 899: 165981, 2023 Nov 15.
Article in English | MEDLINE | ID: mdl-37572898

ABSTRACT

Groundwater quality management, crucial for ensuring sustainable water resources and public health, is the scope of this study. Our objective is to demonstrate the significance of secondary data analysis for the spatiotemporal characterization of groundwater quality. To this end, we develop and employ a robust trend analysis method, in tandem with a spatiotemporal data aggregation method, to accurately identify shifts in groundwater quality over time, even in the face of inflection points or breakpoints. The methods and results reveal diverse trends and characteristics in water quality over space and time across the entire dataset from selected regions in South Korea, emphasizing the importance of analyzing aggregated data beyond individual business locations. The conclusions indicate that this study contributes to the development of more reliable and effective groundwater quality management strategies by addressing gaps in traditional monitoring methods and the challenges of limited monitoring resources and uneven data quality. Future research directions include the application of the developed methods to other regions and data sources, opening avenues for further advances in groundwater quality management.

9.
Nat Commun ; 14(1): 793, 2023 Feb 11.
Article in English | MEDLINE | ID: mdl-36774360

ABSTRACT

Structural colors provide a promising visualization with high color saturation, iridescent characteristics, and fade resistance. However, pragmatic uses are frequently impeded by complex manufacturing processes for sophisticated nanostructures. Here, we report a facile emulsion-templating strategy to produce crescent-shaped microparticles as structural color pigments. The micro-crescents exhibit brilliant colors under directional light originating from total internal reflections and optical interferences in the absence of periodic nanostructures while being transparent under ambient light. The colors are finely tunable by adjusting the size of the micro-crescents, which can be further mixed to enrich the variety. Importantly, the pre-defined convex surface secures high stability of colors and enables structural coloration on target surfaces through direct deposition as inks. We anticipate this class of nanostructure-free structural colorants is pragmatic as invisible inks in particular for anti-counterfeiting patches and color cosmetics with distinctive impressions due to low-cost, scalable manufacturing, unique optical properties, and versatility.

10.
Nat Sci Sleep ; 14: 1737-1751, 2022.
Article in English | MEDLINE | ID: mdl-36187326

ABSTRACT

Purpose: Sleep quality among military service members is important for enhancing their capabilities and preventing psychiatric problems. We aimed to explore the association of dietary behaviors with poor sleep quality and increased risk of obstructive sleep apnea (OSA) in military men on active duty. Patients and Methods: A large-scale multi-site cross-sectional survey was conducted in five units of the Republic of Korea's army. Poor sleep quality and increased risk of OSA were defined using the Pittsburgh sleep quality index (PSQI) and Berlin Questionnaire, respectively. Information on dietary behaviors, including the frequency of skipping breakfast, eating snacks, consuming a night meal, and overeating, were collected. Results: From August 2021 to September 2021, 4389 male respondents, mean age (20.8 ± 1.3 years), completed the survey; 2579 (58.8%) were assessed as having poor sleep quality, and 614 (14.0%) increased risk of OSA. After adjusting for lifestyle and occupational covariates, skipping breakfast 1-2 times weekly was associated with an increased likelihood of experiencing poor sleep quality, compared with not skipping breakfast (odds ratio: 1.23 [95% CI 1.02-1.47]). Eating night meals 5-6 times weekly was also associated with poor sleep quality (odds ratio: 5.54 [95% CI 2.49-14.18]). In addition, skipping breakfast daily (odds ratio: 2.28 [95% CI 1.27-4.03]) and eating night meals daily (odds ratio: 2.30 [95% CI 1.21-4.22]) were related to an increased risk of OSA. Conclusion: Dietary behaviors appear to be related to poor sleep quality and a high risk of OSA. To improve sleep quality, dietary factors could be considered when promoting health programs for military personnel in further research.

11.
Chemosphere ; 286(Pt 3): 131916, 2022 Jan.
Article in English | MEDLINE | ID: mdl-34416582

ABSTRACT

Adsorption is an effective method for the removal of inorganic and organic contaminants and has been commonly used as a pretreatment method to improve contaminant removal and control flux during membrane filtration. Over the last two decades, many researchers have reported the use of hybrid systems comprising various adsorbents and different types of membranes, such as nanofiltration (NF), ultrafiltration (UF), and microfiltration (MF) membranes, to remove contaminants from water. However, a comprehensive evaluation of the removal mechanisms and effects of the operating conditions on the transport of contaminants through hybrid systems comprising various adsorbents and NF, UF, or MF membranes has not been performed to date. Therefore, a systematic review of contaminant removal using adsorption-membrane hybrid systems is critical, because the transport of inorganic and organic contaminants via the hybrid systems is considerably affected by the contaminant properties, water quality parameters, and adsorbent/membrane physicochemical properties. Herein, we provide a comprehensive summary of the most recent studies on adsorption-NF/UF/MF membrane systems using various adsorbents and membranes for contaminant removal from water and wastewater and highlight the future research directions to address the current knowledge gap.


Subject(s)
Membranes, Artificial , Water Purification , Adsorption , Ultrafiltration , Wastewater
12.
Chemosphere ; 290: 133395, 2022 Mar.
Article in English | MEDLINE | ID: mdl-34952026

ABSTRACT

Contaminants of emerging concerns such as endocrine-disrupting compounds (EDCs) and pharmaceuticals/personal-care products (PPCPs) constitute a problem since they are not completely eliminated by traditional water and wastewater treatment methods. Non-thermal plasma (NTP) is considered as one of the most favorable treatment methods for the removal of organic contaminants in water and wastewater. The degradation of selected EDCs and PPCPs of various classes was reviewed, based on the recent literature, to (i) address the effect of the main NTP treatment parameters (water quality and NTP conditions: pH, initial concentration, temperature, background common ion, NOM, scavenger, gas type/flow rate, discharge/reactor type, input power, and energy efficiency/yield) on the degradation of contaminants and their intermediates, (ii) assess the influences of different catalysts and hybrid systems on degradation, (iii) describe EDC and PPCP degradation along with their properties, and (iv) evaluate mineralization, pathway, and degradation mechanism of selected EDCs and PPCPs for different cases studied. Furthermore, areas of potential research in NTP treatment for the degradation of EDCs and PPCPs in aqueous solutions are recommended. It could be reasonably predicted that this review is valid for developing our understanding of the fundamental scientific principles concerning the catalytic NTP of EDCs and PPCPs, providing helpful and practical references for researchers and designers on the effective removal of EDCs/PPCPs and the optimized operation of catalytic NTP systems.


Subject(s)
Cosmetics , Endocrine Disruptors , Pharmaceutical Preparations , Plasma Gases , Water Pollutants, Chemical , Endocrine Disruptors/analysis , Water Pollutants, Chemical/analysis
13.
J Hazard Mater ; 426: 128120, 2022 03 15.
Article in English | MEDLINE | ID: mdl-34953257

ABSTRACT

Single and multilayered Ti3C2TX MXene (referred to as SLM and MLM in this study, respectively) was applied as catalysts in the ultrasonic (US) process to treat selected pharmaceutical compounds including diclofenac and verapamil (VRP). Due to solid surface, elemental composition, and functional groups of Ti3C2TX MXene, the free OH• production was increased by 48.8% for the US treatment with SLM and 59.8% for the US treatment with MLM compared with the US-only treatment. Additionally, adsorption affected the performance during the US treatment in the presence of the catalyst. Thus, the US treatment in the presence of Ti3C2TX MXene had an enhanced performance not only because of increased oxidation but also because of adsorption, particularly between positively charged VRP and negatively charged Ti3C2TX MXene. Moreover, although the degradation of the performance was higher for SLM (85.1%) than for MLM (81.8%), by improving the dispersion and reducing the size via sonication, the US treatment in the presence of MLM showed the highest synergy effect. In other words, the US treatment in the presence of MLM showed higher performance than the simple sum of oxidation and adsorption. These findings confirm that the US treatment in the presence of MLM may be a promising technology to treat various pharmaceuticals as a more degradable, strongly reusable, and less toxic process.


Subject(s)
Diclofenac , Titanium , Adsorption , Oxidation-Reduction , Verapamil
14.
J Comput Assist Tomogr ; 45(5): 684-690, 2021.
Article in English | MEDLINE | ID: mdl-34407059

ABSTRACT

OBJECTIVE: We evaluated the prognostic impacts of body composition components measured by computed tomography (CT) in patients with liver cirrhosis. METHODS: A total of 160 cirrhotic patients who underwent CT and hepatic venous pressure gradient measurements were retrospectively enrolled. Cross-sectional areas of skeletal muscle, visceral and subcutaneous fat, and mean CT attenuation of trabecular bone of the fourth lumbar vertebral level (L4HU) were measured. RESULTS: Multivariate analysis showed model for end-stage liver disease score [hazard ratio (HR), 1.086; 95% confidence interval (CI), 1.020-1.156; P = 0.010], hepatic venous pressure gradient (HR, 1.076; 95% CI, 1.021-1.135; P = 0.006), sarcopenia (HR, 1.890; 95% CI, 1.032-3.462; P = 0.039), and L4HU (HR, 1.960 for L4HU <145 Hounsfield units; 95% CI, 1.094-3.512; P = 0.024) were independently associated with long-term mortality. In patients with decompensated cirrhosis, subcutaneous adipose tissue index was the only independent predictor (HR, 0.984; 95% CI, 0.969-0.999; P = 0.039). CONCLUSION: Body composition abnormalities determined by CT are associated with long-term prognosis in cirrhotic patients.


Subject(s)
Body Composition , Bone Density , End Stage Liver Disease/diagnostic imaging , Liver Cirrhosis/mortality , Sarcopenia/diagnostic imaging , Tomography, X-Ray Computed/methods , Adipose Tissue/diagnostic imaging , End Stage Liver Disease/mortality , Female , Humans , Male , Middle Aged , Muscle, Skeletal/diagnostic imaging , Predictive Value of Tests , Prognosis , Republic of Korea/epidemiology , Retrospective Studies , Sarcopenia/mortality , Severity of Illness Index , Survival Analysis
15.
Langmuir ; 37(33): 10150-10158, 2021 Aug 24.
Article in English | MEDLINE | ID: mdl-34384020

ABSTRACT

As a step toward the bottom-up construction of magnonic systems, this paper demonstrates the use of a large-amplitude surface-pressure annealing technique to generate 2-D order in a Langmuir-Blodgett monolayer of magnetic soft spheres comprising a surfactant-encapsulated polyoxometalate. The films show a distorted square lattice interpreted as due to geometric frustration caused by 2-D confinement between soft walls, one being the air interface and the other the aqueous subphase. Hysteresis and relaxation phenomena in the 2-D layers are suggested to be due to folding and time-dependent interpenetration of surfactant chains.

16.
J Cancer ; 12(14): 4288-4294, 2021.
Article in English | MEDLINE | ID: mdl-34093829

ABSTRACT

Background: As the number of long-term survivors of solid cancers keeps increasing, risk assessment of secondary hematologic malignancies is important for the prognosis of the patient. Germline genetic predisposition to secondary hematologic malignancy has been studied widely in myeloid neoplasms and rarely in lymphoid neoplasms. This study aimed to profile the mutational spectrums of patients with subsequent lymphoid tissue neoplasm to shed some light on the understudied area. Methods: In total, 39 patients who had primary solid cancer and subsequent hematologic malignancies were enrolled. We performed two next-generation sequencing (NGS) panel tests encompassing hereditary cancer predisposition genes and genes related to clonal hematopoiesis of indeterminate potential (CHIP). All statistical analyses were performed using R 3.5.1. Results: We found 8 of 39 patients with germline mutations in cancer predisposition genes; 4 of 18 patients had therapy-related myeloid neoplasms (22.2%); and 4 of 15 patients had secondary lymphoid malignancies (26.7%). Notably, of 14 patients who initially suffered from thyroid cancer, 5 patients (35.7%) had germline mutations. Malignancy of lymphoid tissue showed no association with radioactive iodine therapy but was observed to a greater extent in germline mutation-positive thyroid cancer patients regardless of their history of treatment. We observed that 24 of 39 patients (61.5%) were CHIP carriers. Patients who had secondary lymphoid malignancy were less likely to have CHIP than those who had myeloid malignancy. Conclusions: In patients with primary solid cancer who are planning to undergo cytotoxic chemotherapy, radiotherapy, or radioactive iodine therapy, an initial assessment with germline mutation testing using an expanded NGS panel, including low, moderate, and high-risk cancer-associated genes, and somatic CHIP mutation testing can screen the patients who are at risk of developing therapy-related myeloid and lymphoid malignancies. Through careful screening and monitoring throughout the treatment process, patients can benefit from the early detection of secondary malignancies and receive proper treatment.

17.
Chemosphere ; 277: 130332, 2021 Aug.
Article in English | MEDLINE | ID: mdl-33784557

ABSTRACT

As the marine industry develops, the importance of seawater treatment process is increasing. To treat seawater, oxidation processes have primarily been used, such as ballast water treatment systems, aquaculture farm operations, aquarium management, and seawater desalination. However, dissolved organic matter in seawater, whose characteristics vary spatially and seasonally, affects the efficiency of oxidation processes. Therefore, in this study, seawater samples were acquired from various locations in the Republic of Korea to understand the spatio-temporal patterns of marine dissolved organic matter. It was reported that the characterization of marine dissolved organic matter using liquid chromatography-organic carbon detector and excitation-emission matrix-parallel factor modeling. Furthermore, the effects of marine dissolved organic matter were evaluated on ozonation, an oxidation process. The results demonstrate that marine dissolved organic matter varies in its aquagenic, pedogenic, and intermediate characteristics based on region and season. These variations affect ozonation by influencing the consumption of oxidants (e.g., bromine). As a result, it was concluded that characterizing marine dissolved organic matter can help improve the effectiveness of oxidation processes, particularly ozonation.


Subject(s)
Ozone , Water Purification , Aquaculture , Republic of Korea , Seawater , Spectrometry, Fluorescence
18.
Article in English | WPRIM (Western Pacific) | ID: wpr-874307

ABSTRACT

AbstractThe demand for natural substances with anti-melanogenic activity is increasing due to the recent interest in skin whitening. Intensive investigation on the culture broth of Streptomyces sp. SCO-736, a marine bacterium from the Antarctica coast, has led to the isolation of a new natural product named antaroide (1). The chemical structure was established through the interpretation of MS, UV, and NMR spectroscopic data. Antaroide is a nine-membered macrolide with lactone and lactam moieties. To investigate its applicability in skin whitening cosmetics, its anti-melanogenic activity in B16F10 murine melanoma cells was examined. As a result, antaroide displayed strong inhibitory activities against melanin synthesis and also attenuated the dendrite formation induced by the α-melanocyte stimulating hormone (α-MSH). Antaroide suppressed the mRNA expression of the melanogenic enzymes such as tyrosinase, TRP-1 and TRP-2. This suggests that it may serve as a transcriptional regulator of melanogenesis. Collectively, the discovery of this novel natural nine-membered macrolide and its anti-melanogenic activity could give new insights for the development of skin whitening agents.

19.
ACS Nano ; 14(11): 15714-15722, 2020 Nov 24.
Article in English | MEDLINE | ID: mdl-33191732

ABSTRACT

Colloidal crystals show structural colors through wavelength-selective diffraction at photonic stopbands. Here, we design photonic Janus balls with a controlled magnetic moment for programmable structural color switching. The Janus balls are produced from microfluidically produced paired drops of two distinct photocurable resins. The lighter resin contains magnetic nanoparticles and carbon black, whereas heavier one contains silica particles at a high volume fraction. The paired drops spontaneously align vertically due to the density asymmetry. The magnetic moment is assigned in the vertically aligned drops by aligning magnetic nanoparticles with an external field and capturing them through photopolymerization. Silica particles in the heavier compartment spontaneously form crystalline arrays due to interparticle repulsion, developing structural colors. The resulting photonic Janus balls vertically align without an external field, like a roly-poly toy, so that carbon-black-laden compartments face upward. With an external magnetic field, the Janus balls align their magnetic moment to the field and display structural colors. Importantly, the direction of the magnetic moment is set by the direction of the external field during photopolymerization, which enables the simultaneous manipulation of orientations of distinct photonic Janus balls in a programmed manner. These photonic Janus balls are potentially useful as active color inks for anti-counterfeiting tags.

20.
Mycobiology ; 48(5): 423-426, 2020 Jul 20.
Article in English | MEDLINE | ID: mdl-33177922

ABSTRACT

Cypripedium japonicum is known to be the indigenous plant to Korea, Japan, and China. However, C. japonicum represents the most critically endangered plant species in South Korea. The plant is esthetically pleasing due to its flower, which is larger than any other orchidaceous species. Disease symptoms relating to gray mold were observed on C. japonicum in May 2019. The suspected pathogen was successfully isolated from the symptomatic leaf tissue and conducted a pure culture of the fungi. The conidia formed consisted of a colorless or light brown single cell, which was either egg or oval-shaped with a size of 7.1 to 13.4 × 5.2 to 8.6 µm. Molecular phylogenetic relationship analysis was also confirmed that the pathogen concerned belonging to the family of Botrytis cinerea. Therefore, the findings confirmed that the pathogen isolated from C. japonicum was consistent with the unique properties of B. cinerea.

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