Effect of chlorination and ultraviolet on the adsorption of pefloxacin on polystyrene and polyvinyl chloride.

During the water treatment process, chlorination and ultraviolet (UV) sterilization can modify microplastics (MPs) and alter their physicochemical properties, causing various changes between MPs and other pollutants. In this study, the impact of chlorination and UV modification on the physicochemical properties of polystyrene (PS) and polyvinyl chloride (PVC) were investigated, and the adsorption behavior of pefloxacin (PEF) before and after modification was examined. The effect of pH, ionic strength, dissolved organic matter, heavy metal ions and other water environmental conditions on adsorption behavior was revealed. The results showed that PS had a higher adsorption capacity of PEF than PVC, and the modification increased the presence of O-containing functional groups in the MPs, thereby enhancing the adsorption capacity of both materials. Chlorination had a more significant impact on the physicochemical properties of MPs compared to UV irradiation within the same time period, leading to better adsorption performance of chlorination. The optimal pH for adsorption was found to be 6, and NaCl, sodium alginate and Cu2+ would inhibit adsorption to varying degrees, among which the inhibition caused by pH was the strongest. Chlorination and UV modification would weaken the inhibitory effect of environmental factors on the adsorption of PEF by MPs. The main mechanisms of adsorption involved electrostatic interaction and hydrogen bonding. The study clarified the effects of modification on the physicochemical properties of MPs, providing reference for subsequent biotoxicity analysis and environmental protection studies.

A dopant-assisted iodide-adduct chemical ionization time-of-flight mass spectrometer based on VUV lamp photoionization for atmospheric low-molecular-weight organic acids analysis.

Formic and acetic acids are the most abundant gaseous organic acids and play the key role in the atmospheric chemistry. In iodine-adduct chemical ionization mass spectrometry (CIMS), the low utilization efficiency of methyl iodide and humidity interference are two major issues of the vacuum ultraviolet (VUV) lamp initiated CIMS for on-line gaseous formic and acetic acids analysis. In this work, we present a new CIMS based on VUV lamp, and the ion-molecular reactor is separated into photoionization and chemical ionization zones by a reducer electrode. Acetone was added to the photoionization zone, and the VUV photoionization acetone provided low-energy electrons for methyl iodide to generate I-, and the addition of acetone reduced the amount of methyl iodide by 2/3. In the chemical ionization zone, a headspace vial containing ultrapure water was added for humidity calibration, and the vial changes the sensitivity as a function of humidity from ambiguity to well linear correlation (R2 > 0.95). With humidity calibration, the CIMS can quantitatively measure formic and acetic acids in the humidity range of 0%-88% RH. In this mode, limits of detection of 10 and 50 pptv are obtained for formic and acetic acids, respectively. And the relative standard deviation (RSD) of quantitation stability for 6 days were less than 10.5%. This CIMS was successfully used to determine the formic and acetic acids in the underground parking and ambient environment of the Shandong University campus (Qingdao, China). In addition, we developed a simple model based formic acid concentration to assess vehicular emissions.

The photo-based treatment technology simultaneously removes resistant bacteria and resistant genes from wastewater.

Because of the recent widespread usage of antibiotics, the acquisition and dissemination of antibiotic-resistance genes (ARGs) were prevalent in the majority of habitats. Generally, the biological wastewater treatment processes used in wastewater treatment plants have a limited efficiencies of antibiotics resistant bacteria (ARB) disinfection and ARGs degradation and even promote the proliferation of ARGs. Problematically, ARB and ARGs in effluent pose potential risks if they are not further treated. Photocatalytic oxidation is considered a promising disinfection technology, where the photocatalytic process generates many free radicals that enhance the interaction between light and deoxyribonucleic acid (DNA) for ARB elimination and subsequent degradation of ARGs. This review aims to illustrate the progress of photocatalytic oxidation technology for removing antibiotics resistant (AR) from wastewater in recent years. We discuss the sources and transfer of ARGs in wastewater. The overall removal efficiencies of ultraviolet radiation (UV)/chlorination, UV/ozone, UV/H2O2, and UV/sulfate-radical based system for ARB and ARGs, as well as the experimental parameters and removal mechanisms, are systematically discussed. The contribution of photocatalytic materials based on TiO2 and g-C3N4 to the inactivation of ARB and degradation of ARGs is highlighted, producing many free radicals to attack ARB and ARGs while effectively limiting the horizontal gene transfer (HGT) in wastewater. Finally, based on the reviewed studies, future research directions are proposed to realize specific photocatalytic oxidation technology applications and overcome current challenges.

Degradation of carbamazepine by the UVA-LED365/ClO2/NaClO process: Kinetics, mechanisms and DBPs yield.

A mixed oxidant of chlorine dioxide (ClO2) and NaClO was often used in water treatment. A novel UVA-LED (365 nm)-activated mixed ClO2/NaClO process was proposed for the degradation of micropollutants in this study. Carbamazepine (CBZ) was selected as the target pollutant. Compared with the UVA365/ClO2 process, the UVA365/ClO2/NaClO process can improve the degradation of CBZ, with the rate constant increasing from 2.11×10-4 sec-1 to 2.74×10-4 sec-1. In addition, the consumption of oxidants in the UVA365/ClO2/NaClO process (73.67%) can also be lower than that of UVA365/NaClO (86.42%). When the NaClO ratio increased, both the degradation efficiency of CBZ and the consumption of oxidants can increase in the UVA365/ClO2/NaClO process. The solution pH can affect the contribution of NaClO in the total oxidant ratio. When the pH range of 6.0-8.0, the combination process can generate more active species to promote the degradation of CBZ. The change of active species with oxidant molar ratio was investigated in the UVA365/ClO2/NaClO process. When ClO2 acted as the main oxidant, HO• and Cl• were the main active species, while when NaClO was the main oxidant, ClO• played a role in the system. Both chloride ion (Cl-), bicarbonate ion (HCO3-), and nitrate ion (NO3-) can promote the reaction system. As the concentration of NaClO in the reaction solution increased, the generation of chlorates will decrease. The UVA365/ClO2/NaClO process can effectively control the formation of volatile disinfection by-products (DBPs), and with the increase of ClO2 dosage, the formation of DBPs can also decrease.

The Tiny Big Difference: Nanotechnology in Photoprotective Innovations - A Systematic Review.

UV radiation causes long- and short-term skin damage, such as erythema and skin cancer. Therefore, the use of sunscreens is extremely important. However, concerns about UV filter safety have prompted exploration into alternative solutions, with nanotechnology emerging as a promising avenue. This systematic review identified 23 experimental studies utilizing nanocarriers to encapsulate sunscreens with the aim of enhancing their efficacy and safety. Polymeric and lipid nanoparticles are frequently employed to encapsulate both organic and inorganic UV filters along with natural antioxidants. Nanocarriers have demonstrated benefits including reduced active ingredient usage, increased sun protection factor, and mitigated photoinstability. Notably, they also decreased the skin absorption of UV filters. In summary, nanocarriers represent a viable strategy for improving sunscreen formulations, offering enhanced physicochemical properties and bolstered photoprotective effects, thereby addressing concerns regarding UV filter safety and efficacy in cosmetic applications.

Variability in the acid adaptation of ten different O157:H7 and non-O157 Escherichia coli strains in orange juice and the impact on UV radiation resistance.

This study aimed to assess the impact of adaptation of ten strains of O157:H7 and non-O157 Escherichia coli to low pH (acid shock or slow acidification) and the effects of this exposure or not on the resistance of E. coli strains to UV radiation in orange juice (pH 3.5). The acid-shocked cells were obtained through culture in tryptic soy broth (TSB) with a final pH of 4.8, which was adjusted by hydrochloric, lactic, or citric acid and subsequently inoculated in orange juice at 4 °C for 30 days. No significant differences (p > 0.05) in survival in orange juice were observed between the serotypes O157:H7 and non-O157:H7 for acid-shocked experiments. After slow acidification, where the cells were cultured in TSB supplemented with glucose 1% (TSB + G), a significant increase (p < 0.05) in survival was observed for all strains evaluated. The D-values (radiation dose (J/cm2) necessary to decrease the microbial population by 90%) were determined as the inverse of the slopes of the regressions (k) obtained by plotting log (N/N0). The results show that among the strains tested, E. coli O157:H7 (303/00) and O26:H11 were the most resistant and sensitive strains, respectively. According to our results, the method of acid adaptation contributes to increasing the UV resistance for most of the strains tested.

Prospective Objective Analysis of Corneal Haze Following Customized Transepithelial PRK Without Mitomycin C Combined With Accelerated Corneal Cross-Linking Versus Corneal Cross-Linking Alone.

PURPOSE: To compare haze and refractive outcomes in patients undergoing combined accelerated corneal cross-linking (A-CXL) and selective wavefront-guided transepithelial photorefractive keratectomy (WG-transPRK) without mitomycin C (MMC) versus those undergoing A-CXL. METHODS: This prospective study analyzed 95 eyes (86 patients) with progressive keratoconus from October 2018 to October 2022. The first group underwent CXL combined with corneal or ocular WG-transPRK (CXL+PRK, n = 52), targeting higher order aberrations (HOAs). The second underwent CXL only (n = 43), both following the same accelerated CXL protocol without MMC on the SCHWIND Amaris laser platform (SCHWIND eye-tech-solutions). Baseline and postoperative evaluations (1, 3, 6, and 12 months) included uncorrected (UDVA) and corrected (CDVA) distance visual acuity, manifest refraction, tomography, corneal HOAs, and optical coherence tomography (OCT) scans. A patented machine learning algorithm objectively detected and quantified stromal haze on OCT scans in grayscale units. RESULTS: In both groups, anterior corneal haze reflectivity and subepithelial haze peaked at 3 months postoperatively, then progressively decreased at 6 and 12 months. Haze did not differ between groups at any time point. By 12 months, CDVA increased by 2.5 lines in the CXL+PRK group (P < .001) and by 0.7 lines in the CXL group (P = .10), and maximum keratometry decreased from 51.70 ± 5.10 to 47.90 ± 7.90 diopters (D) (CXL+PRK group) (P < .001) and from 51.20 ± 5.10 to 50.30 ± 4.60 D (CXL group) (P = .004). Corneal HOAs decreased in both groups but more in the CXL+PRK group. CONCLUSIONS: Combining CXL with WG-transPRK without MMC does not result in increased haze when compared to A-CXL alone. This combined approach achieves greater improvements in visual, topographic, and aberrometric parameters. [J Refract Surg. 2024;40(9):e583-e594.].

Molecular Mechanisms of Polyphenols in Management of Skin Aging.

The natural process of skin aging is influenced by a variety of factors, including oxidative stress, inflammation, collagen degradation, and UV radiation exposure. The potential of polyphenols in controlling skin aging has been the subject of much investigation throughout the years. Due to their complex molecular pathways, polyphenols, a broad class of bioactive substances present in large quantities in plants, have emerged as attractive candidates for skin anti-aging therapies. This review aims to provide a comprehensive overview of the molecular mechanisms through which polyphenols exert their anti-aging effects on the skin. Various chemical mechanisms contribute to reducing skin aging signs and maintaining a vibrant appearance. These mechanisms include UV protection, moisturization, hydration, stimulation of collagen synthesis, antioxidant activity, and anti-inflammatory actions. These mechanisms work together to reduce signs of aging and keep the skin looking youthful. Polyphenols, with their antioxidant properties, are particularly noteworthy. They can neutralize free radicals, lessening oxidative stress that might otherwise cause collagen breakdown and DNA damage. The anti-inflammatory effects of polyphenols are explored, focusing on their ability to suppress pro-inflammatory cytokines and enzymes, thereby alleviating inflammation and its detrimental effects on the skin. Understanding these mechanisms can guide future research and development, leading to the development of innovative polyphenol-based strategies for maintaining healthy skin.

Sex-specific responses of Taxus mairei to UV-B radiation involved altering the interactions between the microbiota assembly and host secondary metabolism.

BACKGROUND: To adapt to constantly changing environments, ancient gymnosperms have coevolved with diverse endophytic fungi that are essential for the fitness and adaptability of the plant host. However, the effect of sex on plant-endophyte interactions in response to environmental stressors remains unknown. RNA-seq integrated with ITS analysis was applied to reveal the potential mechanisms underlying the sex-specific responses of Taxus mairei to ultraviolet (UV)-B radiation. RESULTS: Enrichment analysis suggested that sex influenced the expression of several genes related to the oxidation-reduction system, which might play potential roles in sex-mediated responses to UV-B radiations. ITS-seq analysis clarified the effects of UV-B radiation and sex on the composition of endophytic fungal communities. Sex influenced various secondary metabolic pathways, thereby providing chemicals for T. mairei host to produce attractants and/or inhibitors to filter microbial taxa. Analysis of fungal biomarkers suggested that UV-B radiation reduced the effect of sex on fungal communities. Moreover, Guignardia isolate #1 was purified to investigate the role of endophytic fungi in sex-mediated responses to UV-B radiation. Inoculation with spores produced by isolate #1 significantly altered various oxidation-reduction systems of the host by regulating the expression of APX2, GST7 NCED1, ZE1, CS1, and CM1. CONCLUSION: These results revealed the roles of endophytic fungi in sex-mediated responses to UV-B radiation and provided novel insights into the sex-specific responses of Taxus trees to environmental stressors. Video Abstract.

Long-lasting, UV shielding, and cellulose-based avermectin nano/micro spheres with dual smart stimuli-microenvironment responsiveness for Plutella xylostella control.

The requirement to improve the efficiency of pesticide utilization has led to the development of sustainable and smart stimuli-responsive pesticide delivery systems. Herein, a novel avermectin nano/micro spheres (AVM@HPMC-Oxalate) with sensitive stimuli-response function target to the Lepidoptera pests midgut microenvironment (pH 8.0-9.5) was constructed using hydroxypropyl methylcellulose (HPMC) as the cost-effective and biodegradable material. The avermectin (AVM) loaded nano/micro sphere was achieved with high AVM loading capacity (up to 66.8 %). The simulated release experiment proved the rapid stimuli-responsive and pesticides release function in weak alkaline (pH 9) or cellulase environment, and the release kinetics were explained through release models and SEM characterization. Besides, the nano/micro sphere size made AVM@HPMC-Oxalate has higher foliar retention rate (1.6-2.1-fold higher than commercial formulation) which is beneficial for improving the utilization of pesticides. The in vivo bioassay proved that AVM@HPMC-Oxalate could achieve the long-term control of Plutella xylostella by extending UV shielding performance (9 fold higher than commercial formulation). After 3 h of irradiation, the mortality rate of P. xylostella treated by AVM@HPMC-Oxalate still up to 56.7 % ± 5.8 %. Moreover, AVM@HPMC-Oxalate was less toxic to non-target organisms, and the acute toxicity to zebrafish was reduced by 2-fold compared with AVM technical.

Light-emitting diode irradiation at 590 nm combined with active substances modulates ultraviolet B radiation-induced keratinocyte inflammation.

To evaluate the efficacy of yellow light-emitting diode (LED) irradiation at 590 nm, alone or in combination with anti-inflammatory active substances against ultraviolet (UV)-induced inflammation in keratinocytes. HaCaT keratinocytes were pretreated with LED yellow light (590 nm) alone or in combination with an antiinflammatory active substance such as glycerophosphoinositol choline (GC), extract of grains of paradise (Aframomum melegueta Schum, AM), or a bisabolol and ginger root extract mixture (Bb-GE) before UVB irradiation. Following each treatment, we measured the levels of inflammatory mediators secreted by keratinocytes. HaCaT keratinocytes treated with UVB (300 mJ cm-²) and then cultured for 24 h exhibited significantly upregulated expression of proinflammatory factors, including interleukin (IL)-1α, prostaglandin E2 (PGE2), and IL-8. After pretreatment with 590 nm LED, UVB-induced inflammatory responses were significantly inhibited. Co-pretreatment with 590 nm LED irradiation and GC further inhibited the expression of IL-1α and IL-8. IL-8 expression was inhibited by co-pretreatment with 590 nm LED irradiation and AM, whereas PGE2 expression was inhibited by co-pretreatment with 590 nm LED irradiation and Bb-GE. Co-treatment with 590 nm LED irradiation and various active substances modulated UVB-induced inflammation in keratinocytes, suggesting the potential application of this approach to prevent damage caused by voluntary sun exposure in daily life.

Trifarotene alleviates skin photoaging injury by inhibition of JNK/c-Jun/MMPs.

Long-term exposure to ultraviolet (UV) radiation induces skin photoaging, which manifests as oxidative stress, inflammation, and collagen degradation. Multiple approaches (topical or systemic retinoids, antioxidants, alpha-hydroxy acids, laser, surgery) are used in the treatment of photoaged skin, and the use of topical retinoids is currently a primary clinical treatment. Previous studies revealed that retinoic acid promotes keratinocyte proliferation and reduces melanin deposition and matrix metalloproteinase (MMP) secretion; it also causes potential allergic and inflammatory damage to the skin. This study aimed to investigate the therapeutic effects and mechanisms of trifarotene, a functional retinoic acid analog, on UV-irradiated photoaging ICR and BALB/c nude mice and UVB photodamaged human epidermal keratinocyte (HaCaT) cells by examining indicators such as collagen, oxidoreductase, and inflammatory factor presence through histochemical staining, Western blot, and ELISA. Results suggested that trifarotene significantly reduced UV-induced photoaging in mouse skin tissue, potentially by reducing oxidative stress damage and inflammatory factor release, and inhibiting melanin deposition and collagen degradation by downregulating MMP expression. Concentrations of malondialdehyde, tyrosinase, interleukin-6, interleukin- 12, and tumor necrosis factor-alpha in photoaged skin decreased, while SOD content in photodamaged HaCaT cells significantly increased. Trifarotene (3.3 µmol L-1) inhibited phosphorylated JNK and c-Jun expression both independently and collaboratively with the JNK activator anisomycin, demonstrating that trifarotene mitigates UV-induced collagen degradation and apoptosis through inhibition of the JNK/c-Jun/MMPs signaling pathway.

Cosmeceuticals in photoaging: A review.

BACKGROUND: Photoaging is a process of the architecture of normal skin damaged by ultraviolet radiation. Topical cosmeceuticals have been used to treat this condition. The authors aimed to understand the mechanism and level of evidence of different commonly used cosmeceuticals used to treat photodamaged skin. OBJECTIVE: A range of commonly used topical cosmeceuticals (botanicals, peptides, and hydroquinone) has been used in cosmetic medicine for many years to treat photodamaged skin. This review article compares their efficacy and level of evidence. MATERIAL AND METHODS: This study was a systematic review to evaluate the efficacy of different topical cosmeceuticals. Keywords including "Photoaging," "Azelaic acid," "Soy," "Green Tea," "Chamomile," "Ginkgo," "Tea Tree Oil," "Resveratrol," "Cucumber," "Ginseng," "Centella asiatica," "Licorice Root," "Aloe Vera," "Peptides," "Argireline," "Hydroquinone," were typed on OVID, PUBMED, MEDLINE for relevant studies published on photoaging treatment. RESULTS: Most of the evidence behind cosmeceuticals is of high-quality ranging from Level I to Level II. In particular, the evidence base behind peptides is the strongest with most studies achieving Level Ib status in the evidence hierarchy. CONCLUSION: Topical cosmeceuticals like botanicals, peptides and hydroquinone can effectively treat photodamaged skin.

The mechanism of UV accelerated aging of polyvinyl chloride in marine environment: The role of free radicals.

This study systematically investigated the photo-aging of polyvinyl chloride (PVC) in deionized water, estuary water, and seawater. As the concentration of Cl- increases, the carbonyl index (CI) of PVC during photo aging also increases, indicating that Cl- plays a dominant role in PVC photoaging in the environment, which enhance carbonyl index and •OH radical accumulation. Unlike previous studies, this study discovered that halogen radicals were also generated during PVC aging. Compared to •OH radicals, halogen radicals exhibit stronger selectivity and are more conducive to the photo aging of PVC. Additionally, it was found that PVC shows specific toxicity to Paramecia caudatum at various concentrations both before and after aging, affecting the reproduction process of Paramecia caudatum. This study elucidates the mechanism by which anions in natural water bodies affect the rate of PVC aging, providing a scientific basis for understanding the photodegradation of MPs in the ocean.

Development of strontium aluminate-printed nonwoven fabric from recycled cotton cellulose for smart wearable photochromic applications.

Smart photochromic and fluorescent textile refers to garments that alter their colorimetric properties in response to external light stimulus. Cotton fibers have been reported as a main resource for many textile and non-textile industries, such as automobiles, medical devices, and furniture applications. Cotton is a natural fiber that is distinguished with breathability, softness, cheapness, and highly absorbent. However, there have been growing demands to find other resources for cotton textiles at high quality and low cost for various applications, such as sensor for harmful ultraviolet radiation. Herein, we present a novel method toward luminescent and photochromic nonwoven textiles from recycled cotton waste. Using the screen-printing technology, a cotton fabric that is both photochromic and fluorescent was developed using aqueous inorganic phosphor nanoparticles (10-18 nm)-containing printing paste. Both CIE Lab color coordinates and photoluminescence spectra showed that the transparent film printed on the nonwoven fabric develops a reversible green emission (519 nm) under ultraviolet light (365 nm), even at low pigment concentration (2%) in the printing paste. Colorfastness of printed fabrics showed high durability and photostability.

Effects of UV-B and UV-C Spectrum Supplementation on the Antioxidant Properties and Photosynthetic Activity of Lettuce Cultivars.

Indoor farming systems enable plant production in precisely controlled environments. However, implementing stable growth conditions and the absence of stress stimulants can weaken plants' defense responses and limit the accumulation of bioactive, health-beneficial phytochemicals. A potential solution is the controlled application of stressors, such as supplemental ultraviolet (UV) light. To this end, we analyzed the efficiency of short-term pre-harvest supplementation of the red-green-blue (RGB, LED) spectrum with ultraviolet B (UV-B) or C (UV-C) light to boost phytochemical synthesis. Additionally, given the biological harm of UV radiation due to high-energy photons, we monitored plants' photosynthetic activity during treatment and their morphology as well as sensory attributes after the treatment. Our analyses showed that UV-B radiation did not negatively impact photosynthetic activity while significantly increasing the overall antioxidant potential of lettuce through enhanced levels of secondary metabolites (total phenolics, flavonoids, anthocyanins), carotenoids, and ascorbic acid. On the contrary, UV-C radiation-induced anthocyanin accumulation in the green leaf cultivar significantly harmed the photosynthetic apparatus and limited plant growth. Taken together, we showed that short-term UV-B light supplementation is an efficient method for lettuce biofortification with healthy phytochemicals, while UV-C treatment is not recommended due to the negative impact on the quality (morphology, sensory properties) of the obtained leafy products. These results are crucial for understanding the potential of UV light supplementation for producing functional plants.

Photodegradation of Amoxicillin in Aqueous Systems: A Review.

Amoxicillin (AMX) is utilized in the treatment of several infectious diseases, and its concentration in wastewater has increased quite significantly over the years, posing high health hazards for humans and other living organisms. Investigations are in progress globally to eliminate AMX and other related pollutants using several methods that include adsorption, photolysis, photocatalytic degradation, photoelectrocatalytic degradation, and electrochemical conversion. AMX can be eliminated efficiently from the environment using photodegradation, either by photolysis or a photocatalytic process. Several types of semiconductor NMs have been used to eliminate AMX and other related drugs present in wastewater. This review spans the photodegradation studies conducted during the years 2018-2024 to degrade and eliminate AMX in aquatic systems. Several studies have been reported to eliminate AMX from different water streams. These studies are categorized into TiO2-containing and non-TiO2-based catalysts for better comparison. A section on photolysis is also included, showing the use of UV alone or with H2O2 or PS without using any nanomaterial. A tabulated summary of both types of catalysts showing the catalysts, reaction conditions, and degradation efficiency is presented. Researchers have used a variety of reaction conditions that include radiation types (UV, solar, and visible), pH of the solution, concentration of AMX, number of nanomaterials, presence of other additives and activators such as H2O2 as oxidant, and the influence of different salts like NaCl and CaCl2 on the photodegradation efficiency. TiO2 was the best nanomaterial found that achieved the highest degradation of AMX in ultraviolet irradiation. TiO2 doped with other nanomaterials showed very good performance under visible light. WO3 was also used by several investigators and found quite effective for AMX degradation. Other metal oxides used for AMX elimination were derived from molybdenum, zinc, manganese, copper, cerium, silver, etc. Some researchers have used UV and/or visible irradiation or sunlight, without using solid catalysts, in the presence of oxidants such as H2O2. A summarized description of earlier published reviews is also presented.