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1.
Materials (Basel) ; 17(9)2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38730961

RESUMO

Zirconium carbide (ZrC) ceramics have a high melting point, low neutron absorption cross section, and excellent resistance to the impact of fission products and are considered to be one of the best candidate materials for fourth-generation nuclear energy systems. ZrC ceramics with a high relative density of 99.1% were successfully prepared via pressureless sintering using a small amount of MoSi2 as an additive. The influence of the MoSi2 content on the densification behavior, microstructure, mechanical properties, and thermal properties of ZrC ceramics was systematically investigated. The results show that the densification of ZrC was significantly enhanced by the introduction of MoSi2 due to the formation of a liquid phase during sintering. In addition, the ZrC grains were refined due to the pinning effect of the generated silicon carbide. The flexural strength and Vickers hardness of ZrC ceramics with 2.5 vol% MoSi2 sintered at 1850 °C were 408 ± 12 MPa and 17.1 GPa, respectively, which were approximately 30% and 10% higher compared to the samples without the addition of MoSi2. The improved mechanical properties were mainly attributed to the high relative density (99.1%) and refined microstructure.

2.
Front Neurosci ; 18: 1349059, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38560046

RESUMO

Introduction: Acupuncture analgesia (AA) is widely used in clinical practice. The autonomic nervous system (ANS) may be an important pathway for acupuncture signal transduction. However, real-time changes in autonomic function during AA and the effect of "needle sensation" remain unclear. Methods: We established a human pain model in healthy adults and randomly assigned 128 participants to the model, sham acupuncture, and acupuncture groups in a 1:1:2 ratio. Heart rate variability (HRV), including total power (TP), low-frequency power (LF), high-frequency power (HF), ratio of LF to HF (LF/HF), standard deviation of the normal-normal intervals (SDNN), and root mean square of successive interval differences (RMSSD), were used to assess autonomic function. The visual analog scale (VAS) and efficiency were used to assess the analgesic effect of acupuncture. The Massachusetts General Hospital acupuncture sensation scale (MASS) was used to indicate the intensity of the needle sensation. Anxiety levels were also measured. Finally, the correlation of MASS with HRV, VAS, and anxiety levels was analyzed. Results: VAS decreased after 10 min of needling and 5 min after needle withdrawal in the acupuncture group compared with those in the model group (p = 0.038, p = 0.020). The efficacy rates were 82.0, 50.0, and 61.3% in the acupuncture, model, and sham groups, respectively. These represent significant differences between the acupuncture group and the model and sham acupuncture groups (p < 0.001 in each case). No differences were observed between the model and sham acupuncture groups. HF, TP, SDNN, and RMSSD were all increased in the acupuncture group compared with those in the model group (p = 0.045, p = 0.041, p = 0.002, p = 0.006, respectively). No differences were observed in the sham acupuncture group compared to the model group (p = 0.632, p = 0.542, p = 0.093, p = 0.222, respectively). The LF and LF/HF did not differ among all three groups. A positive correlation was observed between MASS and RMSSD2, LF2, RMSSD4, TP4, VAS5, and anxiety levels. Conclusion: AA was associated with enhanced vagal activity. The intensity of needle sensation was positively correlated with vagal and sympathetic nerve activities. Acupuncture is an effective means of regulating autonomic function, and needle sensation may be an important modulator.

3.
Artigo em Inglês | MEDLINE | ID: mdl-38619792

RESUMO

PURPOSE: The internal carotid artery (ICA) is a region with a high incidence for small- and medium-sized saccular aneurysms. However, the treatment relies heavily on the surgeon's experience to achieve optimal outcome. Although the finite element method (FEM) and computational fluid dynamics can predict the postoperative outcomes, due to the computational complexity of traditional methods, there is an urgent need for investigating the fast but versatile approaches related to numerical simulations of flow diverters (FDs) deployment coupled with the hemodynamic analysis to determine the treatment plan. METHODS: We collected the preoperative and postoperative data from 34 patients (29 females, 5 males; mean age 55.74 ± 9.98 years) who were treated with a single flow diverter for small- to medium-sized intracranial saccular aneurysms on the ICA. The constraint-based virtual deployment (CVD) method is proposed to simulate the FDs expanding outward along the vessel centerline while be constrained by the inner wall of the vessel. RESULTS: The results indicate that there were no significant differences in the reduction rates of wall shear stress and aneurysms neck velocity between the FEM and methods. However, the solution time of CVD was greatly reduced by 98%. CONCLUSION: In the typical location of small- and medium-sized saccular aneurysms, namely the ICA, our virtual FDs deployment simulation effectively balances the computational accuracy and efficiency. Combined with hemodynamics analysis, our method can accurately represent the blood flow changes within the lesion region to assist surgeons in clinical decision-making.

4.
Materials (Basel) ; 17(7)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38612122

RESUMO

The effects of Ti doping on the microstructure and properties of SiCp/Al composites fabricated by pressureless infiltration were comprehensively investigated using first-principles calculations and experimental analyses. First-principles calculations revealed that the interface wetting and bonding strength in an Al/SiC system could be significantly enhanced by Ti doping. Subsequently, the Ti element was incorporated into SiC preforms in the form of TiO2 and TiC to verify the influence of Ti doping on the pressureless infiltration performance of SiCp/Al composites. The experimental results demonstrated that the pressureless infiltration of molten Al into SiC preforms was promoted by adding TiC or TiO2 due to the improved wettability. However, incorporating TiO2 leads to the growth of AlN whiskers under a N2 atmosphere, thereby hindering the complete densification of the composites. On the other hand, TiC doping can improve wettability and interface strength without deleterious reactions. As a consequence, the TiC-doped SiCp/Al composites exhibited excellent properties, including a high relative density of 99.4%, a bending strength of 287 ± 18 MPa, and a thermal conductivity of 142 W·m-1·K-1.

5.
Water Res ; 256: 121588, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38636120

RESUMO

So far, little has been known about how the combined collection systems of sewage and rainfall runoff (CCSs) affect emerging contaminants in river water. To fill up the knowledge gap, this study was conducted to investigate the spatial distributions of three natural estrogens (NEs, i.e., estrone (E1), 17ß-estradiol (E2) and estriol (E3)) and their conjugates (C-NEs) in the Pearl River in the wet and dry seasons. Results showed that the respective average concentrations of NEs and C-NEs at different locations alongside the Pearl River in the wet season were 7.3 and 1.8 times those in the dry season. Based on estrogen equivalence (EEQ), the average estimated EEQ level in the Pearl River waters in the wet season was nearly 10 times that in the dry season. These seemed to imply that the CCSs in the wet season not only cause untreated sewage into the receiving water body, but greatly decrease the removal efficiency of NEs and C-NEs in wastewater treatment plant. Furthermore, the estimated annual loads of E1, E2, and E3 to the Pearl River in the wet season accounted for about 88.6 %, 100 %, and 99.3 % of the total annual loads. Consequently, this work for the first time demonstrated that the CCSs in cities with high precipitation are unfavorable for controlling of emerging contaminants.


Assuntos
Monitoramento Ambiental , Estrogênios , Chuva , Rios , Esgotos , Poluentes Químicos da Água , Rios/química , China , Estrogênios/análise , Esgotos/química , Poluentes Químicos da Água/análise , Estações do Ano , Estrona/análise , Estradiol/análise
6.
Nat Commun ; 15(1): 2636, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38528028

RESUMO

Conventional food production is restricted by energy conversion efficiency of natural photosynthesis and demand for natural resources. Solar-driven artificial food synthesis from CO2 provides an intriguing approach to overcome the limitations of natural photosynthesis while promoting carbon-neutral economy, however, it remains very challenging. Here, we report the design of a hybrid electrocatalytic-biocatalytic flow system, coupling photovoltaics-powered electrocatalysis (CO2 to formate) with five-enzyme cascade platform (formate to sugar) engineered via genetic mutation and bioinformatics, which achieves conversion of CO2 to C6 sugar (L-sorbose) with a solar-to-food energy conversion efficiency of 3.5%, outperforming natural photosynthesis by over three-fold. This flow system can in principle be programmed by coupling with diverse enzymes toward production of multifarious food from CO2. This work opens a promising avenue for artificial food synthesis from CO2 under confined environments.

7.
Sci Total Environ ; 926: 172071, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38554960

RESUMO

Natural estrogen conjugates play important roles in municipal wastewater treatment plant (WWTP), but their deconjugation potentials are poorly understood. This work is the first to investigate the relationships between the enzyme activities of arylsulfatase/ß-glucuronidase and deconjugation potentials of natural estrogen conjugates. This work led to three important findings. First, the enzyme activity of ß-glucuronidase in sewage is far higher than that of arylsulfatase, while their corresponding activities in activated sludge were similar. Second, a model based on ß-glucuronidase could successfully predict the deconjugation potentials of natural estrogen glucuronide conjugates in sewage. Third, the enzyme activity of arylsulfatase in sewage was too low to lead to evident deconjugation of sulfate conjugates, which means that the deconjugation rate of estrogen sulfates can be regarded as zero. By comparing their theoretical removal based on enzyme activity and on-site investigation, it is reasonable to conclude that reverse deconjugation of estrogen conjugates (i.e., conjugation of natural estrogens to form conjugated estrogens) likely exist in WWTP, which explains well why natural estrogen conjugates cannot be effectively removed in WWTP. Meanwhile, this work provides new insights how to improve the removal performance of WWTP on natural estrogen conjugates. SYNOPSIS: This work is the first to show how arylsulfatase/ß-glucuronidase could affect deconjugation of natural estrogen conjugates and possible way to enhance their removal in wastewater treatment plant.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Esgotos , Poluentes Químicos da Água/análise , Estrogênios , Arilsulfatases , Glucuronidase
8.
J Exp Clin Cancer Res ; 42(1): 339, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38098044

RESUMO

BACKGROUND: Within the tumor immune microenvironment (TME), tumor-associated macrophages (TAMs) are crucial in modulating polarization states to influence cancer development through metabolic reprogramming. While long non-coding RNAs (lncRNAs) have been shown to play a pivotal role in the progression of various cancers, the underlying mechanisms by which lncRNAs alter M2 polarization through macrophage metabolism remodeling remain unelucidated. METHODS: RNA sequencing was used to screen for differentially expressed lncRNAs in TAMs and normal tissue-resident macrophages (NTRMs) isolated from pancreatic ductal adenocarcinoma (PDAC) tissues, whilst RT-qPCR and FISH were employed to detect the expression level of SNHG17. Moreover, a series of in vivo and in vitro experiments were conducted to assess the functions of SNHG17 from TAMs in the polarization and glycolysis of M2-like macrophages and in the proliferation and metastasis of pancreatic cancer cells (PCs). Furthermore, Western blotting, RNA pull-down, mass spectrometry, RIP, and dual-luciferase assays were utilized to explore the underlying mechanism through which SNHG17 induces pro-tumor macrophage formation. RESULTS: SNHG17 was substantially enriched in TAMs and was positively correlated with a worse prognosis in PDAC. Meanwhile, functional assays determined that SNHG17 promoted the malignant progression of PCs by enhancing M2 macrophage polarization and anaerobic glycolysis. Mechanistically, SNHG17 could sponge miR-628-5p to release PGK1 mRNA and concurrently interact with the PGK1 protein, activating the pro-tumorigenic function of PGK1 by enhancing phosphorylation at the T168A site of PGK1 through ERK1/2 recruitment. Lastly, SNHG17 knockdown could reverse the polarization status of macrophages in PDAC. CONCLUSIONS: The present study illustrated the essential role of SNHG17 and its molecular mechanism in TAMs derived from PDAC, indicating that SNHG17 might be a viable target for PDAC immunotherapy.


Assuntos
Carcinoma Ductal Pancreático , MicroRNAs , Neoplasias Pancreáticas , RNA Longo não Codificante , Humanos , Fosforilação , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Anaerobiose , Linhagem Celular Tumoral , Proliferação de Células/genética , Neoplasias Pancreáticas/patologia , Carcinoma Ductal Pancreático/patologia , Macrófagos/metabolismo , Glicólise , MicroRNAs/genética , Microambiente Tumoral , Fosfoglicerato Quinase/genética , Fosfoglicerato Quinase/metabolismo
9.
ISA Trans ; 143: 557-571, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37806820

RESUMO

This paper addresses the problem of stochastic modeling of atomic ensembles under multi-source noise and makes the model interpretable. First, based on Itô's lemma and Allan variance analysis (ITÔ-AVAR), an approach is proposed to model nonstationary stochastic submodels of atomic ensembles. On this basis, the variance decomposition and nonlinear optimization algorithms are utilized to hybridize modeling atomic ensembles with nonlinear and nonstationary properties. Second, an Itô's lemma dynamic allan variance analysis (ITÔ-DAVAR) approach is developed for online modeling of atomic ensembles. Further, an atomic ensembles sensitivity enhancement scheme based on the proposed approach is given, which effectively promotes the progress of quantum instrument engineering. Finally, the proposed scheme are deployed in the optical pumping magnetometer and spin-exchange relaxation-free comagnetometer, respectively, while experimentally verifying the sensitivity of the spin-exchange relaxation-free comagnetometer reaches 5.36×10-6degs-1Hz-1/2.

10.
Plants (Basel) ; 12(20)2023 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-37896006

RESUMO

This work aims at studying the molecular mechanisms underlying the response of Reaumuria soongorica to salt stress. We used RNA sequencing (RNA-Seq) and Tandem Mass Tag (TMT) techniques to identify differentially expressed genes (DEGs) and differentially expressed proteins (DEPs) in R. soongorica leaves treated with 0, 200, and 500 mM NaCl for 72 h. The results indicated that compared with the 0 mM NaCl treatment group, 2391 and 6400 DEGs were identified in the 200 and 500 mM NaCl treatment groups, respectively, while 47 and 177 DEPs were also identified. Transcriptome and proteome association analysis was further performed on R. soongorica leaves in the 0/500 mM NaCl treatment group, and 32 genes with consistent mRNA and protein expression trends were identified. SYP71, CS, PCC13-62, PASN, ZIFL1, CHS2, and other differential genes are involved in photosynthesis, vesicle transport, auxin transport, and other functions of plants, and might play a key role in the salt tolerance of R. soongorica. In this study, transcriptome and proteome association techniques were used to screen candidate genes associated with salt tolerance in R. soongorica, which provides an important theoretical basis for understanding the molecular mechanism of salt tolerance in R. soongorica and breeding high-quality germplasm resources.

11.
Environ Sci Pollut Res Int ; 30(52): 112908-112921, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37843706

RESUMO

There have been many analytical methods for natural estrogens in commercial dairy milk samples, but in most of which, only four major estrogens (estrone (E1), 17ß-estradiol (E2), estriol (E3), and 17α-estradiol (αE2)) were included. This work developed an effective GC-MS analytical method for simultaneous analysis of twelve natural estrogens in commercial dairy milk sample, in which eight far-less well-known natural estrogens (2-hydroxyestone (2OHE1), 4-hydroxyestrone (4OHE1), 2-hydroxyestradiol (2OHE2), 4-hydroxyestradiol (4OHE2), 16-epiestriol (16epiE3), 16α-hydroxyestrone (16αOHE1), 16-ketoestradiol (16ketoE2) and 17epiestriol (17epiE3)) were included besides the four major natural estrogens. With liquid-liquid extraction and solid phase extraction, twelve natural estrogens in commercial dairy milk could be effectively extracted. The established method showed good linearity (R2 > 0.9991), low limits of detections (LODs, 0.02-0.11 ng/g), as well as excellent recoveries (64-117%) with satisfactory low relative standard deviations (RSDs, 0.8-14.7%). This established method was applied to seven commercial dairy milk samples, and all the twelve natural estrogens were frequently detected except for 4OHE2 without detection in any sample. Our results showed that the concentration contribution ratios of the eight far-less well-known natural estrogens in commercial dairy milk samples contributed to 32-83%, while the corresponding contribution ratios based on estrogen equivalence (EEQ) were 21-62%. This work highlighted the high abundance of the eight far-less well-known natural estrogens in commercial dairy milk based on both concentration and EEQ, which has been neglected for a long time.


Assuntos
Estrogênios , Leite , Animais , Estrogênios/análise , Cromatografia Gasosa-Espectrometria de Massas , Leite/química , Estradiol/análise , Estriol/análise , Extração em Fase Sólida/métodos , Extração Líquido-Líquido , Cromatografia Líquida de Alta Pressão/métodos
12.
ACS Appl Bio Mater ; 6(10): 4269-4276, 2023 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-37774367

RESUMO

Exosomes are natural endogenous extracellular vesicles with phospholipid-based bilayer membrane structures. Due to their unique protein-decorated membrane properties, exosomes have been regarded as promising drug carriers to deliver small molecules and genes. A number of approaches have been developed for exosome-based drug loading. However, the drug loading capability of exosomes is inconsistent, and the effects of loading methods on the therapeutic efficacy have not been investigated in detail. Herein, we developed anti-inflammatory drug-loaded exosomes as an immunomodulatory nanoplatform. Naïve macrophage-derived exosomes (Mϕ-EVs) were loaded with the anti-inflammatory drug mycophenolic acid (MPA) by three major loading methods. Loading into exosomes significantly enhanced anti-inflammatory and antioxidation effects of MPA in vitro compared to free drugs. These findings provide a scientific basis for developing naïve macrophage-secreted exosomes as drug carriers for immunotherapy.


Assuntos
Vesículas Extracelulares , Mioblastos Cardíacos , Ácido Micofenólico/farmacologia , Portadores de Fármacos/química , Macrófagos , Anti-Inflamatórios
13.
Environ Sci Pollut Res Int ; 30(46): 103153-103163, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37682440

RESUMO

Phthalic acid ester (PAE) contamination in popular drink bubble tea has been hardly studied in the world. In this work, a liquid-liquid extraction following solid phase extraction (LLE-SPE)-UPLC-MS/MS method was first established for trace determination of ten PAEs in bubble tea. The developed method was validated with respect to linearity (R2 > 0.992), low limit of detections (LODs, 0.49-3.16 µg/L), and satisfactory recoveries (61.8-127.6%) with a low relative standard derivations (RSDs, 1.1-16.4%), which was also validated for commercial milk. Six out of ten PAEs, i.e., diethylhexyl phthalate (DEHP), dibutyl phthalate (DBP), diisobutyl phthalate (DIBP), diethyl phthalate (DEP), dihexyl phthalate (DHP), and diphenyl phthalate (DPP) were detected in Chinese bubble tea with concentrations ranging from not detection (ND) to 53.43 µg/L, while DEHP, DBP, DIBP, DEP, and dimethyl phthalate (DMP) were detected in commercial milk with concentrations ranging from ND to 110.58 µg/L. The respective average concentrations of DEHP in Chinese bubble tea and commercial milk were 19.40 and 23.46 µg/L, which were over two times that in drinking water quality standards of several countries including Israel, Korea, Oman, and Singapore (i.e., 8 µg/L). Calculated with human estimated daily intake (EDI), the average EDIs of five out of seven PAEs in bubble tea were higher than those in commercial milk. For example, the calculated EDI of DIBP in bubble tea was 5 times that in commercial milk, while their respective corresponding EDIs of DBP and DEHP were over 2.4 and 1.6 times. Based on estrogen equivalence (EEQ) with the unit of ng E2/L, the average EEQs of the ten PAEs in Chinese bubble tea and commercial milk were 14.26 and 17.06 ng E2/L, which were 52.8 and 62.3 times the observed effect concentration that could cause egg mortality of zebrafish. It is evident that the potential estrogenic effect of PAEs in bubble tea and commercial milk cannot be negligible. Given the fact that PAE contamination in bubble tea has been hardly investigated, such study is urgently to be performed in a global view.

14.
PeerJ ; 11: e15881, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37641597

RESUMO

Hydrogen sulfide (H2S), as an endogenous gas signaling molecule, plays an important role in plant growth regulation and resistance to abiotic stress. This study aims to investigate the mechanism of exogenous H2S on the growth and development of Reaumuria soongorica seedlings under salt stress and to determine the optimal concentration for foliar application. To investigate the regulatory effects of exogenous H2S (donor sodium hydrosulfide, NaHS) at concentrations ranging from 0 to 1 mM on reactive oxygen species (ROS), antioxidant system, and osmoregulation in R. soongorica seedlings under 300 mM NaCl stress. The growth of R. soongorica seedlings was inhibited by salt stress, which resulted in a decrease in the leaf relative water content (LRWC), specific leaf area (SLA), and soluble sugar content in leaves, elevated activity levels of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT); and accumulated superoxide anion (O2-), proline, malondialdehyde (MDA), and soluble protein content in leaves; and increased L-cysteine desulfhydrase (LCD) activity and endogenous H2S content. This indicated that a high level of ROS was produced in the leaves of R. soongorica seedlings and seriously affected the growth and development of R. soongorica seedlings. The exogenous application of different concentrations of NaHS reduced the content of O 2-, proline and MDA, increased the activity of antioxidant enzymes and the content of osmoregulators (soluble sugars and soluble proteins), while the LCD enzyme activity and the content of endogenous H2S were further increased with the continuous application of exogenous H2S. The inhibitory effects of salt stress on the growth rate of plant height and ground diameter, the LRWC, biomass, and SLA were effectively alleviated. A comprehensive analysis showed that the LRWC, POD, and proline could be used as the main indicators to evaluate the alleviating effect of exogenous H2S on R. soongorica seedlings under salt stress. The optimal concentration of exogenous H2S for R. soongorica seedlings under salt stress was 0.025 mM. This study provides an important theoretical foundation for understanding the salt tolerance mechanism of R. soongorica and for cultivating high-quality germplasm resources.


Assuntos
Sulfeto de Hidrogênio , Tolerância ao Sal , Sulfeto de Hidrogênio/farmacologia , Espécies Reativas de Oxigênio , Plântula , Antioxidantes/farmacologia , Estresse Salino , Peroxidase , Peroxidases , Corantes , Deutério
15.
Environ Sci Pollut Res Int ; 30(37): 88049-88059, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37438504

RESUMO

This study investigated concentration levels of ten bisphenols (BPs) in 13 Chinese commercial fresh low temperature dairy milk samples (fresh milk) of main local and national brands with or without enzyme hydrolysis. The results showed that at least two BPs were detected in each fresh milk sample without enzyme hydrolysis and the respective mean concentrations of bisphenol AF (BPAF), bisphenol B (BPB), bisphenol C (BPC), bisphenol F (BPF), bisphenol A (BPA), bisphenol S (BPS), bisphenol AP (BPAP), bisphenol PP (BPP), bisphenol Z (BPZ), and bisphenol E (BPE) were 0.73, 0.61, 1.86, 0.87, 0.42, 0.11, 1.06, 1.42, 1.5, and 0.04 ng/mL, while their respective detection frequencies ranged from 23.1-92.3%. These results indicated the frequent detection of BPs in fresh milk samples. With enzyme hydrolysis, the respective mean concentrations of BPAF, BPA, BPB, BPC, BPF, BPS, and BPAP were increased 7.1-107.1%, indicating the long-ignored importance of enzyme hydrolysis. The respective average estimated daily intakes (EDIs) of BPA by adult and children in China via fresh milk were 32.5 and 37.5 ng/kg bw/d, indicating that BPA in fresh milk was a crucial source to human. Six out of nine other BPs had higher average EDIs than that of BPA, among which the EDI of BPAP was almost three times that of BPA, suggesting the widespread contamination of other BPs in Chinese fresh milk.


Assuntos
População do Leste Asiático , Leite , Adulto , Animais , Criança , Humanos , Compostos Benzidrílicos/análise , Hidrólise , Leite/química
16.
Water Res ; 243: 120310, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37473512

RESUMO

Bisphenol analogues (BPs) and natural estrogens (NEs) as two important groups of endocrine-disrupting compounds (EDCs) in drinking water treatment plants (DWTPs) have been hardly investigated except bisphenol A (BPA) and three major NEs including estrone (E1), 17ß-estradiol (E2) and estriol (E3). In this study, a GC-MS analytical method was firstly established and validated for trace simultaneous determination of ten BPs and twelve NEs in drinking water, which included BPA, bisphenol B (BPB), bisphenol C (BPC), bisphenol E (BPE), bsiphenol F (BPF), bsiphenol P (BPP), bisphenol S (BPS), bisphenol Z (BPZ), bisphenol AF (BPAF), bisphenol AP (BPAP), E1, E2, E3, 17α-estradiol (17α-E2), 2-hydroestrone (2OHE1), 16hydroxyestrone (16α-OHE1), 4-hydroestrone (4OHE1), 2-hydroxyesstradiol (2OHE2), 4-hydroxyestradiol (4OHE2), 17-epiestriol (17epiE3), 16-epiestriol (16epiE3) and 16keto-estraiol (16ketoE2). This investigation showed that eighteen out of twenty-two targeted compounds were detected in drinking source waters of eight DWTPs with concentrations ranging from not detected to 142.8 ng/L. Although the conventional treatment process of DWTP could efficiently remove both BPs and NEs with respective removal efficiencies of 74.1%-90.9% and 74.5%-100%, BPA, BPS, BPE, BPZ, E1, 2OHE1, and 2OHE2 were found in the finished drinking waters. Chlorination could remove part of BPs and NEs, but the efficiency varied greatly with DWTP and the reason was unknown. In the finished drinking waters of eight DWTPs, the highest chemically calculated estrogen equivalence (EEQ) derived from BPs and NEs was up to 6.11 ngE2/L, which was over 22 times that could do harm to zebrafish, indicating a potential risk to human health. Given the fact that many chlorination products of BPs and NEs likely have higher estrogenic activities, the estrogenic effect of BPs and NEs in finished drinking water should be accurately examined urgently with the inclusion of BPs, NEs as well as their main chlorinated by-products. This study shed new light on the occurrence, removal, and potential estrogenic effects of BPs and NEs in DWTPs.


Assuntos
Água Potável , Purificação da Água , Humanos , Animais , Estrogênios/análise , Peixe-Zebra , Estrona , Estradiol , Compostos Benzidrílicos/química , Estriol
17.
Sci Total Environ ; 891: 164600, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37271397

RESUMO

Ibuprofen and acetaminophen as two anti-fever agents have been widely used in human. Due to lack of full understanding, this work firstly summarized their occurrence and fate in municipal wastewater treatment plants (WWTPs) across 30 countries. The respective influent concentrations of ibuprofen and acetaminophen were not detected (ND)-39,830,000 and ND-66440000 ng/L, while their corresponding respective effluent concentrations were ND-58710 and ND-90500 ng/L. The removal efficiencies of ibuprofen and acetaminophen in municipal WWTPs were 6.5-100 % and 14.3-100 % with respective average removal efficiencies of 87.6 % and 94.7 %. There have been many batch studies on ibuprofen biodegradation with kbio values available, while such investigation for acetaminophen was very limited. The theoretically calculated removal efficiency of ibuprofen with kbio agreed well with that of the observed average removal efficiency of on-site investigations on full-scale WWTP, which was quite different from natural estrogens and some other emerging contaminants. One possible reason is that conjugated ibuprofen could be easily cleaved and the cleavage step gives little effect on the biodegradation of ibuprofen. Due to extremely high concentrations of ibuprofen and acetaminophen in influent of municipal WWTP, their concentration levels in effluent likely high enough to pose adverse effects on some aquatic organisms. To protect water environment, advanced treatment is necessary to further remove residue ibuprofen and acetaminophen in the effluent. To the best of our knowledge, this is the systematical summarization on the occurrence and fate of ibuprofen and acetaminophen in municipal WWTP as well as their potential effect on aquatic organisms, which addressed known knowledge and unknowns to be further investigated.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Humanos , Ibuprofeno , Acetaminofen , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Eliminação de Resíduos Líquidos
18.
Genome Biol ; 24(1): 156, 2023 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-37386475

RESUMO

Prime editing is limited by low efficiency in plants. Here, we develop an upgraded engineered plant prime editor in hexaploid wheat, ePPEplus, by introducing a V223A substitution into reverse transcriptase in the ePPEmax* architecture. ePPEplus enhances the efficiency by an average 33.0-fold and 6.4-fold compared to the original PPE and ePPE, respectively. Importantly, a robust multiplex prime editing platform is established for simultaneous editing of four to ten genes in protoplasts and up to eight genes in regenerated wheat plants at frequencies up to 74.5%, thus expanding the applicability of prime editors for stacking of multiple agronomic traits.


Assuntos
Agricultura , Triticum , Triticum/genética , Fenótipo
19.
Opt Express ; 31(12): 19968-19978, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37381401

RESUMO

This study presents a novel method for measuring the number density of K in K-Rb hybrid vapor cells using circularly polarized pump light on polarized alkali metal atoms. This proposed method eliminates the need for additional devices such as absorption spectroscopy, Faraday rotation, or resistance temperature detector technology. The modeling process involved considering wall loss, scattering loss, atomic absorption loss, and atomic saturation absorption, with experiments designed to identify the relevant parameters. The proposed method is real-time, highly stable, and a quantum nondemolition measurement that does not disrupt the spin-exchange relaxation-free (SERF) regime. Experimental results demonstrate the effectiveness of the proposed method, as the longitudinal electron spin polarization long-term stability increased by 204% and the transversal electron spin polarization long-term stability increased by 44.8%, as evaluated by the Allan variance.

20.
Nat Commun ; 14(1): 2643, 2023 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-37156784

RESUMO

Photoelectrochemical device is a versatile platform for achieving various chemical transformations with solar energy. However, a grand challenge, originating from mass and electron transfer of triphase-reagents/products in gas phase, water/electrolyte/products in liquid phase and catalyst/photoelectrode in solid phase, largely limits its practical application. Here, we report the simulation-guided development of hierarchical triphase diffusion photoelectrodes, to improve mass transfer and ensure electron transfer for photoelectrochemical gas/liquid flow conversion. Semiconductor nanocrystals are controllably integrated within electrospun nanofiber-derived mat, overcoming inherent brittleness of semiconductors. The mechanically strong skeleton of free-standing mat, together with satisfactory photon absorption, electrical conductivity and hierarchical pores, enables the design of triphase diffusion photoelectrodes. Such a design allows photoelectrochemical gas/liquid conversion to be performed continuously in a flow cell. As a proof of concept, 16.6- and 4.0-fold enhancements are achieved for the production rate and product selectivity of methane conversion, respectively, with remarkable durability.

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