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1.
Artículo en Inglés | MEDLINE | ID: mdl-38294757

RESUMEN

Objective: This study aimed to analyze the diagnostic efficacy of serum biomarkers in liver cirrhosis patients categorized by Child-Pugh scores. Methods: An observational cross-sectional study design was employed. A total of 110 liver cirrhosis patients, classified according to Child-Pugh scores and 60 healthy individuals were included in this study. Serum levels of adenosine deaminase (ADA), adiponectin (APN), matrix metalloproteinase-2 (MMP-2), alkaline phosphatase (ALP), alanine aminotransferase (ALT), and aspartate aminotransferase (AST) were measured. Results: The levels of ADA, APN, MMP-2, ALP, ALT, and AST were significantly higher in the study group compared to the control group (P < .05). Furthermore, these levels increased with the severity of liver cirrhosis, with higher levels observed in patients with Child-Pugh class C. The positive diagnostic rates for joint detection in Child-Pugh class A, B, and C were 93.75% (30/32), 100% (34/34), and 100% (44/44), respectively. Conclusions: Combined detection of serum biomarkers improves the diagnostic efficacy of liver cirrhosis. The diagnostic rates were higher when considering Child-Pugh scores, with the highest rates observed in class C.

2.
Ren Fail ; 45(1): 2209392, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37199269

RESUMEN

Objectives: Membranous nephropathy (MN) and minimal change disease (MCD) are two common types of nephrotic syndrome that have similar clinical presentations but require different treatment strategies. Currently, the definitive diagnosis for these conditions relies on invasive renal biopsy, which can be limited in clinical practice.Methods: In this study, we aimed to differentiate idiopathic MN (IMN) from MCD using clinical data and gut microbiota. We collected clinical data and stool samples from 115 healthy individuals, 115 IMN, and 45 MCD at the onset of disease and performed 16S rRNA sequencing. Through machine learning methods including random forest, logistic regression, and support vector machine, a classifier to differentiate IMN from MCD was constructed.Results: Baseline clinical data comparing the IMN and MCD groups showed that the MCD had higher levels of hemoglobin, uric acid, cystatin C, ß2-microglobulin, α1-microglobulin, total cholesterol, and low-density lipoprotein and lower levels of albumin and CD4+ T-cell counts. The gut microbiota of the two groups differed at all levels of the phylum and genus. Differential gut microbiota may disturb the integrity of the intestinal wall and lead to the passage of inflammatory mediators through the intestinal barrier, causing kidney injury. We constructed a noninvasive classifier with a discrimination efficacy of 0.939 that combined the clinical data and gut microbiota information to identify IMN and MCD.Conclusions: The classifier of the gut microbiota combined with clinical indicators has achieved good performance in identifying IMN and MCD, which provides a new approach for the noninvasive discrimination of different pathological types of kidney disease.


Asunto(s)
Microbioma Gastrointestinal , Glomerulonefritis Membranosa , Nefrosis Lipoidea , Humanos , Glomerulonefritis Membranosa/diagnóstico , Glomerulonefritis Membranosa/patología , Nefrosis Lipoidea/diagnóstico , ARN Ribosómico 16S/genética , Riñón/patología
3.
Int J Mol Sci ; 23(10)2022 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-35628244

RESUMEN

Flowers are imperative reproductive organs and play a key role in the propagation of offspring, along with the generation of several metabolic products in flowering plants. In Juglans mandshurica, the number and development of flowers directly affect the fruit yield and subsequently its commercial value. However, owing to the lack of genetic information, there are few studies on the reproductive biology of Juglans mandshurica, and the molecular regulatory mechanisms underlying the development of female and male inflorescence remain unclear. In this study, phytohormones and transcriptomic sequencing analyses at the three stages of female and male inflorescence growth were performed to understand the regulatory functions underlying flower development. Gibberellin is the most dominant phytohormone that regulates flower development. In total, 14,579 and 7188 differentially expressed genes were identified after analyzing the development of male and female flowers, respectively, wherein, 3241 were commonly expressed. Enrichment analysis for significantly enriched pathways suggested the roles of MAPK signaling, phytohormone signal transduction, and sugar metabolism. Genes involved in floral organ transition and flowering were obtained and analyzed; these mainly belonged to the M-type MADS-box gene family. Three flowering-related genes (SOC1/AGL20, ANT, and SVP) strongly interacted with transcription factors in the co-expression network. Two key CO genes (CO3 and CO1) were identified in the photoperiod pathway. We also identified two GA20xs genes, one SVP gene, and five AGL genes (AGL8, AGL9, AGL15, AGL19, and AGL42) that contributed to flower development. The findings are expected to provide a genetic basis for the studies on the regulatory networks and reproductive biology in inflorescence development for J. mandshurica.


Asunto(s)
Juglans , Reguladores del Crecimiento de las Plantas , Regulación de la Expresión Génica de las Plantas , Inflorescencia , Juglans/genética , Juglans/metabolismo , Reguladores del Crecimiento de las Plantas/genética , Reguladores del Crecimiento de las Plantas/metabolismo , Transcriptoma
4.
Int J Mol Sci ; 23(23)2022 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-36499551

RESUMEN

Juglans mandshurica has strong freezing resistance, surviving temperatures as low as -40 °C, making it an important freeze tolerant germplasm resource of the genus Juglans. APETALA2/ethylene responsive factor (AP2/ERF) is a plant-specific superfamily of transcription factors that regulates plant development, growth, and the response to biotic and abiotic stress. In this study, phylogenetic analysis was used to identify 184 AP2/ERF genes in the J. mandshurica genome, which were classified into five subfamilies (JmAP2, JmRAV, JmSoloist, JmDREB, and JmERF). A significant amount of discordance was observed in the 184 AP2/ERF genes distribution of J. mandshurica throughout its 16 chromosomes. Duplication was found in 14 tandem and 122 segmental gene pairs, which indicated that duplications may be the main reason for JmAP2/ERF family expansion. Gene structural analysis revealed that 64 JmAP2/ERF genes contained introns. Gene evolution analysis among Juglandaceae revealed that J. mandshurica is separated by 14.23 and 15 Mya from Juglans regia and Carya cathayensis, respectively. Based on promoter analysis in J. mandshurica, many cis-acting elements were discovered that are related to light, hormones, tissues, and stress response processes. Proteins that may contribute to cold resistance were selected for further analysis and were used to construct a cold regulatory network based on GO annotation and JmAP2/ERF protein interaction network analysis. Expression profiling using qRT-PCR showed that 14 JmAP2/ERF genes were involved in cold resistance, and that seven and five genes were significantly upregulated under cold stress in female flower buds and phloem tissues, respectively. This study provides new light on the role of the JmAP2/ERF gene in cold stress response, paving the way for further functional validation of JmAP2/ERF TFs and their application in the genetic improvement of Juglans and other tree species.


Asunto(s)
Respuesta al Choque por Frío , Juglans , Respuesta al Choque por Frío/genética , Familia de Multigenes , Filogenia , Proteínas de Plantas/metabolismo , Juglans/genética , Juglans/metabolismo , Regulación de la Expresión Génica de las Plantas
5.
Environ Sci Technol ; 55(17): 11733-11744, 2021 09 07.
Artículo en Inglés | MEDLINE | ID: mdl-34369153

RESUMEN

Chemical reactivity, kinetics, degradation pathways and mechanisms, and ecotoxicity of the oxidation of 1-vinyl-3-ethylimidazolium bromide ([VEIm]Br), the most common alternative to organic solvents, by Fe(VI) (HFeO4-) were studied by lab experiments and theoretical calculations. Results show that Fe(VI) can efficiently remove VEIm through the dioxygen transfer-hydrolysis mechanism, which has not been reported yet. The reactivity of VEIm toward Fe(VI) mainly depends on the double bonds in the side chain of VEIm. The second-order rate constant for VEIm was 629.45 M-1 s-1 at pH 7.0 and 25 °C. Typical water constituents, except for SO32-, Cl-, and Cu2+, had no obvious effects on the oxidation. The oxidation products were determined by high-performance liquid chromatography hybrid quadrupole time-of-flight mass spectrometry, which proves that there were interactions between the oxidation intermediates of the anion and cation parts of [VEIm]Br during the degradation process. The structures of related products and oxidation mechanisms were further rationalized by theoretical calculations. The ecotoxicity of products from the three oxidation pathways all showed a trend of increase after the initial decrease. We hope that the findings of this work can give researchers some new inspirations on Fe(VI) degradation of other alkene-containing contaminants.


Asunto(s)
Líquidos Iónicos , Contaminantes Químicos del Agua , Purificación del Agua , Alquenos , Imidazoles , Hierro , Cinética , Oxidación-Reducción , Contaminantes Químicos del Agua/análisis
6.
Ren Fail ; 43(1): 980-992, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34157945

RESUMEN

Diabetic glomerulopathy (DG) remains the prevalent microvascular complication and leading cause of shortened lifespan in type-2 diabetes mellitus (T2DM) despite improvement in hyperglycemia control. Considering the pivotal role of kidney in metabolism, using untargeted metabolomic techniques to globally delineate the serum metabolite profiles will help advance understanding pathogenetic underpinnings of renal biopsy-confirmed DG from the perspective of metabolism specifically. Fourteen pathologically diagnosed DG patients secondary to T2DM and 14 age- and gender-matched healthy controls (HCs) were recruited for study. We employed mass spectrometry-based untargeted metabolomic methods to reveal the metabolite profiles of serum samples collected from all included subjects. We identified a total of 334 and 397 metabolites in positive and negative ion mode respectively. One hundred and eighty-two important differential metabolites whose variable importance in projection (VIP) > 1 and p value <0.05 were selected and annotated to metabolic pathways. KEGG pathway enrichment analysis revealed tryptophan metabolism enriched most significantly. Among the tryptophan derivatives, L-tryptophan (L-Trp) and serotonin were relatively accumulated in DGs compared with HCs, while 5-hydroxyindoleacetic acid (5-HIAA) and indole-3-acetamide were depleted. Correlation analysis showed serotonin and L-Trp are negatively correlated with 24 h urine protein and glycosylated hemoglobin (Ghb). To exclude the interference of preexisting T2DM on DG exacerbation, we selected 5-HIAA and 3-(3-hydroxyphenyl) propionic acid (3-OHPPA) which are not correlated with Ghb and analyzed their correlation relationship with crucial renal indices. We found 3-OHPPA is positively correlated with urine total protein and creatinine ratio (T/Cr) and 24 h urine protein, 5-HIAA is positively correlated with serum creatinine and urea.


Asunto(s)
Diabetes Mellitus Tipo 2/complicaciones , Nefropatías Diabéticas/sangre , Nefropatías Diabéticas/orina , Metabolómica/métodos , Triptófano/metabolismo , Adulto , Estudios de Casos y Controles , Creatinina/sangre , Creatinina/orina , Femenino , Humanos , Modelos Lineales , Masculino , Redes y Vías Metabólicas , Persona de Mediana Edad
7.
Small ; 16(39): e2002808, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32851802

RESUMEN

As stated in the classic Kirchhoff's circuit laws, the total conductance of two parallel channels in an electronic circuit is the sum of the individual conductance. However, in molecular circuits, the quantum interference (QI) between the individual channels may lead to apparent invalidity of Kirchhoff's laws. Such an effect can be very significant in single-molecule circuits consisting of partially overlapped multiple transport channels. Herein, an investigation on how the molecular circuit conductance correlates to the individual channels is conducted in the presence of QI. It is found that the conductance of multi-channel circuit consisting of both constructive and destructive QI is significantly smaller than the addition of individual ones due to the interference between channels. In contrast, the circuit consisting of destructive QI channels exhibits an additive transport. These investigations provide a new cognition of transport mechanism and manipulation of transport in multi-channel molecular circuits.

8.
Ren Fail ; 42(1): 1100-1110, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33121301

RESUMEN

BACKGROUND: Diabetic kidney disease (DKD) and membranous nephropathy (MN) are the two major causes of end-stage renal disease (ESRD). Increasing evidence has shown that intestinal dysbiosis is associated with many diseases. The aim of this study was to explore the composition of the gut microbiome in DKD and MN patients. METHODS: 16S rRNA gene sequencing was performed on 271 fecal samples (DKD = 129 and MN = 142), and taxonomic annotation of microbial composition and function was completed. RESULTS: We observed distinct microbial communities between the two groups, with MN samples exhibiting more severe dysbiosis than DKD samples. Relative increases in genera producing short-chain fatty acids (SCFAs) in DKD and a higher proportion of potential pathogens in MN were the main contributors to the microbiome alterations in the two groups. Five-fold cross-validation was performed on a random forest model, and four operational taxonomic unit (OTU)-based microbial markers were selected to distinguish DKD from MN. The results showed 92.42% accuracy in the training set and 94.52% accuracy in the testing set, indicating high potential for these microbiome-based markers in separating MN from DKD. Overexpression of several amino acid metabolic pathways, carbohydrate metabolism and lipid metabolism was found in DKD, while interconversion of pentose/glucoronate and membrane transport in relation to ABC transporters and the phosphotransferase system were increased in MN. CONCLUSION: The composition of the gut microbiome appears to differ considerably between patients with DKD and those with MN. Thus, microbiome-based markers could be used as an alternative tool to distinguish DKD and MN.


Asunto(s)
Nefropatías Diabéticas/microbiología , Heces/microbiología , Microbioma Gastrointestinal/genética , Glomerulonefritis Membranosa/microbiología , ARN Ribosómico 16S/genética , Nefropatías Diabéticas/diagnóstico , Diagnóstico Diferencial , Disbiosis/microbiología , Glomerulonefritis Membranosa/diagnóstico , Humanos , Curva ROC
9.
Environ Sci Technol ; 53(5): 2705-2712, 2019 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-30726066

RESUMEN

Organic contaminants in water have become one of the most serious environmental problems worldwide. Adsorption is one of the most promising approaches to remove organic pollutants from water. However, the existing adsorbents have relatively low removal efficiency, complex preparation processes, and high cost, which limit their practical applications. Here, we developed three-dimensional (3D) zirconium metal-organic frameworks (MOFs) encapsulated in a natural wood membrane (UiO-66/wood membrane) for highly efficient organic pollutant removal from water. UiO-66 MOFs were in situ grown in the 3D low-tortuosity wood lumens by a facile solvothermal strategy. The resulting UiO-66/wood membrane contains the highly mesoporous UiO-66 MOF structure as well as many elongated and open lumens along the direction of the wood growth. Such a unique structural feature improves the mass transfer of organic pollutants and increases the contact probability of organic contaminants with UiO-66 MOFs as the water flows through the membrane, thereby improving the removal efficiency. Furthermore, the integrated multilayer filter consisting of three pieces of UiO-66/wood membranes exhibits a high removal efficiency (96.0%) for organic pollutants such as rhodamine 6G, propranolol, and bisphenol A at the flux of 1.0 × 103 L·m-2·h-1. The adsorbed capacity of UiO-66/wood for Rh6G (based on the content of UiO-66 MOFs) is calculated to be 690 mg·g-1. We believe that such low-cost and scalable production of the UiO-66/wood membrane has broad applications for wastewater treatment and other related pollutant removal.


Asunto(s)
Contaminantes Ambientales , Estructuras Metalorgánicas , Contaminantes Químicos del Agua , Adsorción , Madera
10.
Biochem Genet ; 57(5): 607-622, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30825077

RESUMEN

Red-flowered strawberry is a new ornamental flower derived from intergeneric hybridization (Fragaria × Potentilla). To date, few molecular markers have been reported for this plant. RNA sequencing provides a relatively fast and low-cost approach for large-scale detection of simple sequence repeats (SSRs). In the present study, we profiled the transcriptome of red-flowered strawberry by Illumina HiSeq 2500 to identify SSRs related to petal color. Based on 2 million clean reads of red and white flowers from red-flowered strawberry hybrids, we assembled 91,835 unigenes with an average length of 717 bp. After functional annotation and prediction, there were 47,058 unigenes; of these, 26,861 had a gene ontology annotation, with 14,264 SSR loci. Mononucleotide SSRs were the predominant repeat type (47.20%, n = 6724), followed by di- (32.50%, n = 4641), tri- (19.10%, n = 2729), tetra- (0.90%, n = 132), hexa- (0.2%, n = 21), and penta- (0.10%, n = 16) nucleotide repeats. The most frequent di-, tri-, and tetra-nucleotide repeats were AG/CT, AAG/CTT, and AAAG/CTTT, respectively. PCR amplification with 105 SSR primer pairs yielded four bands specific to red flowers, namely UgRFsr57622, UgRFsr94149, UgRFsr40142, and UgRFsr54608; corresponding 4 trait-specific markers were found to co-segregate with white and red flower color in hybrid population, demonstrating that the genic SSR marker is useful to discriminate between white and red flowers in strawberry. Markers to discriminate flower color in red-flowered strawberry will be useful for early selection of progeny and for breeding management.


Asunto(s)
Flores , Fragaria , Repeticiones de Microsatélite , Pigmentación/genética , Transcriptoma , Flores/genética , Flores/metabolismo , Fragaria/genética , Fragaria/metabolismo , Perfilación de la Expresión Génica , Marcadores Genéticos
11.
Angew Chem Int Ed Engl ; 56(42): 13031-13035, 2017 10 09.
Artículo en Inglés | MEDLINE | ID: mdl-28763147

RESUMEN

The design and synthesis of high-performance n-type organic semiconductors are important for the development of future organic optoelectronics. Facile synthetic routes to reach the K-region of pyrene and produce 4,5,9,10-pyrene diimide (PyDI) derivatives are reported. The PyDI derivatives exhibited efficient electron transport properties, with the highest electron mobility of up to 3.08 cm2 V-1 s-1 . The tert-butyl-substituted compounds (t-PyDI) also showed good one- and two-photon excited fluorescence properties. The PyDI derivatives are a new family of aromatic diimides that may exhibit both high electron mobility and good light-emitting properties, thus making them excellent candidates for future optoelectronics.

12.
Korean J Physiol Pharmacol ; 20(2): 147-52, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26937210

RESUMEN

Present study aimed to investigate the eff ect of curcumin-pretreatment on intestinal I/R injury and on intestinal mucosa barrier. Thirty Wistar rats were randomly divided into: sham, I/R, and curcumin groups (n=10). Animals in curcumin group were pretreated with curcumin by gastric gavage (200 mg/kg) for 2 days before I/R. Small intestine tissues were prepared for Haematoxylin & Eosin (H&E) staining. Serum diamine oxidase (DAO) and tumor necrosis factor (TNF)-α levels were measured. Expression of intestinal TNF-α and tight junction protein (ZO-1) proteins was detected by Western blot and/or immunohistochemistry. Serum DAO level and serum and intestinal TNF-α leves were signifi cantly increased after I/R, and the values were markedly reduced by curcumin pretreatment although still higher than that of sham group (p<0.05 or p<0.001). H&E staining showed the significant injury to intestinal mucosa following I/R, and curcumin pretreatment signifi cantly improved the histological structure of intestinal mucosa. I/R insult also induced significantly down-regulated expression of ZO-1, and the eff ect was dramatically attenuated by curcumin-pretreatment. Curcumin may protect the intestine from I/R injury through restoration of the epithelial structure, promotion of the recovery of intestinal permeability, as well as enhancement of ZO-1 protein expression, and this eff ect may be partly attributed to the TNF-α related pathway.

13.
Phys Rev E ; 109(4-1): 044143, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38755904

RESUMEN

The dynamic behaviors, specifically trapping and sorting, of active particles interacting with periodic substrates have garnered significant attention. This study investigates numerically the trapping of soft, deformable particles on a periodic potential substrate, which can be experimentally verified through optical tweezers. The research demonstrates that multiple factors, including the relative size of traps, self-propelled velocity, shape parameters, ratio of particles to traps, and translational diffusion, can influence the trapping effect. Within certain parameter boundaries, it is shown that all particles can be consistently trapped. The research reveals that stable trapping typically occurs at median values of the relative trap size. An increase in the self-propelled velocity, the shape parameter, and the translational diffusion coefficient tends to facilitate the escapement of the particles from the traps. It is noteworthy that particles with larger shape parameters can escape even when the restoring force exceeds the self-propelled force. In addition, as the ratio of particles to traps grows, the fraction of trapped particles steadily reduces. Notably, rigid particles are consistently divided and trapped by traps closely approximating an integer multiple of the particles' area, up until the ratio reaches the aforesaid integer value. These findings can potentially enhance the understanding of the interactive effects between active deformable particles and periodic substrates. Moreover, this work suggests a different experimental approach to sort active particles based on rigidity disparities.

14.
J Hazard Mater ; 473: 134630, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38762988

RESUMEN

Decachlorobiphenyl (PCB-209) can be widely detected in suspended particles and sediments due to its large hydrophobicity, and some of its transformation products may potentially threaten organisms through the food chain. Here we investigate the photochemical transformation of PCB-209 on suspended particles from the Yellow River. It was found that the suspended particles had an obvious shielding effect to largely inhibit the photodegradation of PCB-209. Meanwhile, the presence of inorganic ions (e.g. Mg2+ and NO3-) and organic matters (e.g. humic acid, HA) in the Yellow River water inhibited the reaction. The main transformation products of PCB-209 were lower-chlorinated and hydroxylated polychlorinated biphenyls (OH-PCBs), and small amounts of pentachlorophenol (PCP) and polychlorinated dibenzofurans (PCDFs) were also observed. The mechanisms of PCP formation by double •OH attacking carbon bridge and PCDFs formation by elimination reaction of ionic state OH-PCBs were proposed using theoretical calculations, which provided some new insights into the inter-transformations between persistent organic pollutants. In combination with VEGA and EPI Suite software, some intermediates such as PCDFs were more toxic to organisms than PCB-209. This study deepens the understanding of the transformation behavior of PCB-209 on suspended particles under sunlight.

15.
Spectrochim Acta A Mol Biomol Spectrosc ; 318: 124477, 2024 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-38810433

RESUMEN

Hypochlorite (ClO-), as the main component of widely used disinfectants in daily life, comes into closer contact with the human body, which can lead to a number of diseases. The high-performance method is increasingly needed to detect ClO- in our daily life. In this report, we successfully synthesized a FRET ratiometric fluorescent probe (NDAC) containing benzoxadiazole moieties and coumarin moieties bound via ethylenediamine. As expected, NDAC has excellent selectivity and anti-interference ability toward ClO-, and the ratio of fluorescence intensity (I471 nm/I533 nm) has a very good linear relationship with the concentration of ClO-, with a wide linear range (2.5-1750 µM) and low detection limit (0.887 µM). Furthermore, we have successfully applied it for the quantitative detection of ClO- in water samples in daily life. At the same time, there is a very clear change in the fluorescence color after the reaction of the NDAC with ClO-. The blue/green value (B/G) of this color change also shows a very good linear relationship to ClO- (5.0-1000 µM). Therefore, the NDAC has also been successfully used for test strip detection and quantitative detection of ClO- in actual samples through smartphone-based fluorescence image analysis, and this method can provide faster, more convenient and more accessible detection. In addition, NDAC sensors also have potential applications in the field of information anti-counterfeiting.


Asunto(s)
Colorimetría , Transferencia Resonante de Energía de Fluorescencia , Colorantes Fluorescentes , Ácido Hipocloroso , Colorantes Fluorescentes/química , Colorantes Fluorescentes/síntesis química , Ácido Hipocloroso/análisis , Transferencia Resonante de Energía de Fluorescencia/métodos , Colorimetría/métodos , Límite de Detección , Humanos , Desinfectantes/análisis , Cumarinas/química
16.
Environ Pollut ; 346: 123621, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38402942

RESUMEN

Considering that waste incineration fly ash is the main carrier of dioxins and can migrate over long distances in the atmosphere, it is of great significance to study the photochemical transformation behavior of dioxins on the surface of fly ash. In this work, 2-chlorodibenzo-p-dioxin (2-CDD) was selected to conduct a systematic photochemical study. The influence of various factors on the photodegradation of 2-CDD were first explored, and the results showed that small particle size of fly ash, low concentration of 2-CDD and appropriate level of humidity were more conducive to photodegradation, with the highest degradation percentage reaching 76%-84%. The components of fly ash (Zn (Ⅱ), Al (Ⅲ), Cu (Ⅱ) and SiO2) also had a certain promoting effect on the degradation of 2-CDD, which increases the degradation efficiency by 10%-20%, because they could act as effective photocatalysts to produce free radicals for reaction. With a higher total light exposure intensity, natural light environments led to a more complete degradation of 2-CDD than laboratory Xe lamp irradiation (90% degradation Vs. 79% degradation). Based on chemical probe and radical quenching experiment, hydroxyl radical also contributed to 2-CDD photodegradation on fly ash. A total of 16 intermediate products were detected by mass spectrometry analysis, and four initial reaction pathways of 2-CDD were speculated in the process, including dechlorination, ether bond cleavage, hydroxyl substitution, and hydroxyl addition. According to the results of density functional theory calculation, the reaction channels of ether bond cleavage and •OH attack were determined. The toxicity assessment software tool (TEST) was used to assess the toxicity and bioconcentration coefficient of reaction products, and it was found that the overall toxicity of the photodegradation products was reduced. This study would provide new insights into the environmental fate of dioxins during long-range atmospheric migration process.


Asunto(s)
Dioxinas , Metales Pesados , Eliminación de Residuos , Residuos Sólidos/análisis , Dioxinas/análisis , Ceniza del Carbón/análisis , Fotólisis , Dióxido de Silicio , Incineración/métodos , Éteres , Eliminación de Residuos/métodos , Carbono/química , Metales Pesados/análisis
17.
Sci Total Environ ; 924: 171586, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38461975

RESUMEN

Developing efficient and low-cost photocatalytic materials is essential for removing polychlorinated biphenyls (PCBs). In this work, the photodegradation process of fourteen representative polychlorinated biphenyls (PCBs) in both water/nitrogen-doped SiO2 (N-SiO2) and air/N-SiO2 systems was studied. The photodegradation kinetics of PCBs is consistent with the pseudo-first-order kinetic equation. The variation in the degradation effects of different PCBs in the two systems is primarily related to the position of the Cl substituent and the effective absorption wavelength range of PCBs. A total of fourteen intermediates for 4'-Dichlorobiphenyl (PCB-15), 2,2',4,4',6,6'-Hexachlorobiphenyl (PCB-155), and 2,2',3,3',4,4',5,5',6,6'-Decachlorobiphenyl (PCB-209) generated from four reaction pathways were identified based on both mass spectrometry analysis and theoretical calculations. Using the values of lnk (k denotes pseudo-first-order kinetic constants) for the 11 PCBs in the training set and the calculated molecular and structural parameters, quantitative structure-activity relationship (QSAR) models for the two systems were constructed by using multiple linear regression (MLR) method to better understand the factors affecting the photodegradation rate of PCBs. The QSAR equations were obtained with Cl atom substitution at position 3 (N3) as the main parameter, which were lnk = -1.98 - 0.19 N3 for the water/N-SiO2 system and lnk = -1.56 - 0.34 N3 for the air/N-SiO2 system, with the correlation coefficient (R2) of 0.66 and 0.73, leave-one-out cross-validation (Q2LOO) of 0.51 and 0.59, respectively, and bootstrapping validation coefficients (Q2BOOT) values of both 0.74, confirming that the models were well fitted and showed high robustness and prediction ability. This study provides valuable insights into photocatalytic degradation studies of PCBs.

18.
Environ Pollut ; 345: 123541, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38342434

RESUMEN

Polycyclic aromatic hydrocarbons (PAHs) have attracted much attention because of their widespread existence and toxicity. Photodegradation is the main natural decay process of PAHs in soil. The photodegradation kinetics of benzopyrene (BaP) on 16 kinds of soils and 10 kinds of PAHs on Hebei (HE) soil were studied. The results showed that BaP had the highest degradation rate in Shaanxi (SN) soil (kobs = 0.11 min-1), and anthracene (Ant) was almost completely degraded after 16 h of irradiation in HE soil. Two quantitative structure-activity relationship (QSAR) models were established by the multiple linear regression (MLR) method. The developed QSAR models have good stability, robustness and predictability. The model revealed that the main factors affecting the photodegradation of PAHs are soil organic matter (SOM) and the energy gap between the highest occupied molecular orbital and the lowest unoccupied molecular orbital (Egap). SOM can function as a photosensitizer to induce the production of active species for photodegradation, thus favoring the photodegradation of PAHs. In addition, compounds with lower Egap are less stable and more reactive, and thus are more prone to photodegradation. Finally, the QSAR model was optimized using machine learning approach. The results of this study provide basic information on the photodegradation of PAHs and have important significance for predicting the environmental behavior of PAHs in soil.


Asunto(s)
Hidrocarburos Policíclicos Aromáticos , Contaminantes del Suelo , Hidrocarburos Policíclicos Aromáticos/análisis , Suelo , Relación Estructura-Actividad Cuantitativa , Fotólisis , Contaminantes del Suelo/análisis
19.
J Hazard Mater ; 476: 134980, 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38905978

RESUMEN

In this investigation, we conducted a detailed analysis of the oxidation of 16 imidazole ionic liquid variants by Fe(VI) under uniform experimental setups, thereby securing a dataset of second-order reaction rate constants (kobs). This methodology ensures superior data consistency and comparability over traditional methods that amalgamate disparate data from varied studies. Utilizing 16 chemical structural parameters obtained via Density Functional Theory (DFT) as descriptors, we developed a Quantitative Structure Activity Relationship (QSAR) model. Through rigorous correlation analysis, Principal Component Analysis (PCA), Multiple Linear Regression (MLR), and Applicability Domain (AD) evaluation, we identified a pronounced negative correlation between the molecular orbital gap energy (Egap) and kobs. MLR analysis further underscored Egap as a pivotal predictive variable, with its lower values indicating heightened oxidative reactivity towards Fe(VI) in the ionic liquids, leading the QSAR model to achieve a predictive accuracy of 0.95. Furthermore, we integrated an advanced machine learning approach - Random Forest Regression (RFR), which adeptly highlighted the critical factors influencing the oxidation efficiency of imidazole ionic liquids by Fe(VI) through elaborate decision trees, feature importance assessment, Recursive Feature Elimination (RFE), and cross-validation strategies. The RFR model demonstrated a remarkable predictive performance of 0.98. Both QSAR and RFR models pinpointed Egap as a key descriptor significantly affecting oxidation efficiency, with the RFR model presenting lower root mean square errors, establishing it as a more reliable predictive tool. The application of the RFR model in this study significantly improved the model's stability and the intuitive display of key influencing factors, introducing promising advanced analytical tools to the field of environmental chemistry.

20.
Toxics ; 12(5)2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38787140

RESUMEN

Soil contamination of polycyclic aromatic hydrocarbons (PAHs), especially caused by the mixture of two or more PAHs, raised great environmental concerns. However, research on the migration and transformation processes of PAHs in soils and their interactions with native communities is limited. In this work, soil samples from uncontaminated sites around the industrial parks in Handan, Hengshui, and Shanghai were artificially supplemented with three concentrations of anthracene (Ant), 9-chloroanthracene (9-ClAnt), benzopyrene (BaP), and chrysene (Chr). Ryegrass was planted to investigate the degradation of PAHs and its interaction with native soil organisms in the constructed ryegrass-microbe-soil microcosmic system. The bacterial and fungal communities in soil were affected by PAHs; their species diversity and relative abundance changed after exposure to different concentrations of PAHs, among which Lysobacter, Bacillus, Pseudomonas, and Massilia bacteria were correlated to the degradation of PAHs. On the 56th day, the contents of BaP, Chr, and Ant decreased with the degradation process, while the degradation of 9-ClAnt was limited. Nineteen intermediates, including hydroxylation and carboxylated compounds, were identified. The present research would help clarify the potential interactions between PAHs and native organisms in contaminated sites, providing fundamental information for evaluating the transformation risks of PAHs in the natural environment.

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