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1.
Respir Med ; 207: 107117, 2023 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-36626942

RESUMO

Activation of the epidermal growth factor receptor (EGFR) pathway is involved in the pathogenesis of asthma. Although decades of intensive research have focused on the role of EGFR in asthma, the specific mechanisms and pathways of EGFR signaling remain unclear. Various reports have indicated that inhibition of EGFR improves the pathological features in asthma models. However, extending these experimental findings to clinical applications is difficult. Several measures can be adopted to promote clinical application of EGFR inhibitors. This review focuses on the role of EGFR in the pathogenesis of asthma and the development of a potentially novel therapeutic target for asthma.

2.
Anal Chem ; 2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36633187

RESUMO

Research on metabolic heterogeneity provides an important basis for the study of the molecular mechanism of a disease and personalized treatment. The screening of metabolism-related sub-regions that affect disease development is essential for the more focused exploration on disease progress aberrant phenotypes, even carcinogenesis and metastasis. The mass spectrometry imaging (MSI) technique has distinct advantages to reveal the heterogeneity of an organism based on in situ molecular profiles. The challenge of heterogeneous analysis has been to perform an objective identification among biological tissues with different characteristics. By introducing the divide-and-conquer strategy to architecture design and application, we establish here a flexible unsupervised deep learning model, called divide-and-conquer (dc)-DeepMSI, for metabolic heterogeneity analysis from MSI data without prior knowledge of histology. dc-DeepMSI can be used to identify either spatially contiguous regions of interest (ROIs) or spatially sporadic ROIs by designing two specific modes, spat-contig and spat-spor. Comparison results on fetus mouse data demonstrate that the dc-DeepMSI outperforms state-of-the-art MSI segmentation methods. We demonstrate that the novel learning strategy successfully obtained sub-regions that are statistically linked to the invasion status and molecular phenotypes of breast cancer as well as organizing principles during developmental phase.

3.
Bioelectrochemistry ; 150: 108366, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36641842

RESUMO

BACKGROUND: Nanosecond pulsed electric field, with its unique bioelectric effect, has shown broad application potential in the field of tumor therapy, especially in malignant tumors and skin tumors. MAIN BODY: In this paper, we discuss the therapeutic effects and mechanisms of nanosecond pulsed electric field on three common skin cancers, namely, malignant melanoma, squamous cell carcinoma and basal cell carcinoma, as well as its application to other benign skin diseases and future development and improvement directions. CONCLUSION: In general, nanosecond pulsed electric field mainly exerts its ablative effect on tumors through subcellular membrane electroporation effect. It is cell type-specific, has less thermal damage, and can have synergistic effect with chemotherapy drugs, making it a very promising new method for tumor treatment.

4.
J Org Chem ; 2023 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-36700934

RESUMO

An organocatalytic asymmetric C3-allylic alkylation of indolone-2-imines with MBH carbonates has been developed for the first time. As opposed to previous reports, an "interrupted" annulation was achieved, affording 3-allylindoles in generally high yields with excellent stereoselectivities. The representative scale-up reaction and transformation of 3-allylindoles were examined. A possible mechanism was also proposed.

5.
Environ Int ; 172: 107756, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36669285

RESUMO

BACKGROUND: Fine particulate matter (PM2.5) from different source sectors might differ in toxicity. However, data from large-scale studies on vulnerable children in low- and middle-income countries (LMICs) are insufficient. OBJECTIVE: To analyze the association of under-five death (U5D) with long-term exposure to PM2.5 from different sources. METHOD: We evaluated demographic and health survey data for 79,995 babies born in 2017 in 16 Asian and African LMICs (AA-LMICs) and a Latin America low-income country (i.e., Haiti). Long-term exposure to PM2.5 was assessed by a well-established product that attributed the annual concentration to 20 source sectors in 2017. The associations of survival during < 5-year periods with each source-specific concentration of PM2.5 were analyzed by Cox regression with multiple adjustments. We derived a multiple-pollutant ridge regression model to estimate the joint exposure-response function (JERF) between U5D and PM2.5 mixtures. To evaluate how sources affected PM2.5 toxicity, we evaluated the number of U5Ds attributable to PM2.5 based on the source profiles for 88 AA-LMICs. RESULTS: According to the single-pollutant model, the risk of U5D increased by 7% (95% confidence interval [CI]: 5%, 9%) for each 10 µg/m3 increment in total PM2.5 concentration. The model performance was lower than that of the multiple-pollutant ridge regression model. For each 10 µg/m3 increment in PM2.5, the excess risk of U5D ranged from 6% (95% CI: 4%, 9%) in Nepal to 10% (95% CI: 6%, 14%) in Mauritania. Based on the JERF, PM2.5 contributed to 817,647 (95% CI: 585,729, 1,050,439), i.e., 28.0% (95% CI: 20.1%, 35.8%), of all U5Ds across the 88 AA-LMICs. The PM2.5-related U5Ds were mostly attributable to PM2.5 produced by desert dust, followed by solid biofuel combustion and open fires. CONCLUSION: The average toxicity of PM2.5 varied by source profile, which should be taken into consideration when planning public health interventions. For some AA LMICs, natural sources of PM2.5 had the most significant health effects, and should not be ignored to ensure the protection of child health.

6.
Viruses ; 15(1)2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36680191

RESUMO

(1) Background: Largemouth bass virus (LMBV) is a major viral pathogen in largemouth bass (Micropterus salmoides) aquaculture that often causes high mortality and heavy economic losses, thus developing treatments to combat this pathogen is of great commercial importance. Green tea is a well-known medicinal plant that contains active ingredients with antiviral, antibacterial, and other biological activities. The goals of this study were to explore the effect and mechanism of green tea source compounds on LMBV and provide data to serve as the basis for the screening of targeted drugs in the future. In this study, we evaluated the effects of the main component of green tea, epigallocatechin-3-gallate (EGCG), against LMBV infection. (2) Methods: The safe working concentration of EGCG was identified by cell viability detection and light microscopy. The antiviral activity and mechanism of action of EGCG against LMBV infection were evaluated with light microscopy, an aptamer 6-carboxy-fluorescein-based fluorescent molecular probe, and reverse transcription quantitative PCR. (3) Results: The safe working concentration of EGCG was ≤10 µg/mL. EGCG showed significant anti-LMBV infection activity in a concentration-dependent manner, and it also destroyed the structure of virus particles. EGCG impacted the binding of virus particles to cell receptors and virus invasion into the host cells. Inhibitory effects of EGCG on LMBV particles, LMBV binding to the host-cell membrane, and LMBV invasion were 84.89%, 98.99%, and 95.23%, respectively. Meanwhile, the effects of EGCG subsequently were verified in vivo. The fatality rate of the LMBV + EGCG group was significantly lower than that of the LMBV group. (4) Conclusions: Our results suggest that EGCG has effective antiviral properties against LMBV and may be a candidate for the effective treatment and control of LMBV infections in largemouth bass aquaculture.


Assuntos
Bass , Infecções por Vírus de DNA , Doenças dos Peixes , Viroses , Animais , Antivirais/farmacologia , Chá
7.
Environ Pollut ; 320: 121079, 2023 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-36640521

RESUMO

Ambient air pollution exposure may increase the risk of obesity, but the population susceptibility associated with urbanicity has been insufficiently investigated. Based on a nationwide representative cross-sectional survey on 44,544 adults, high-resolution night light satellite remote sensing products, and multi-source ambient air pollution inversion data, the present study evaluated the associations of fine particulate matter (PM2.5) and nitrogen dioxide (NO2) concentrations with the prevalence of obesity and abdominal obesity. We further calculated the associations in regions with different urbanicity levels characterized by both administrative classification of urban/rural regions and night light index (NLI). We found that 10 µg/m3 increments in PM2.5 at 1-year moving average and in NO2 at 5-year moving average were associated with increased prevalence of obesity [odds ratios (OR) = 1.16 (1.14, 1.19); 1.12 (1.09, 1.15), respectively] and abdominal obesity [OR = 1.08 (1.07, 1.10); 1.07 (1.05, 1.09), respectively]. People in rural regions experienced stronger adverse effects than those in urban regions. For instance, a 10 µg/m3 increment in PM2.5 was associated with stronger odds of obesity in rural regions than in urban regions [OR = 1.27 (1.23, 1.31) vs 1.10 (1.05, 1.14), P for interaction <0.001]. In addition, lower NLI values were associated with constantly amplified associations of PM2.5 and NO2 with obesity and abdominal obesity (all P for interaction <0.001). In summary, people in less urbanized regions are more susceptible to the adverse effects of ambient air pollution on obesity, suggesting the significance of collaborative planning of urbanization development and air pollution control, especially in less urbanized regions.

8.
Genomics ; : 110566, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36690262

RESUMO

PURPOSE: Osteosarcoma (OS) is a prevalent bone malignancy mainly occurred in adolescents. WTAP/N6-methyladenosine (m6A) modification is confirmed to be involved in OS progression. This study is conducted to bring some novel insights to the action mechanism of WTAP/m6A under the hidden pathogenesis of OS. METHODS: qRT-PCR was executed to evaluate the expression levels of WTAP and ALB. ALB protein level in OS cells was measured by western blotting. The content of m6A in total RNA was assessed by m6A quantification assay. Me-RIP and dual luciferase reporter assays confirmed the target relationship of WTAP with ALB. With the use of the wound healing, CCK-8, and transwell invasion assays, the functional relationship between WTAP and ALB in OS cells was confirmed. The influences of WTAP on tumor growth in vivo were performed in the xenograft model of mouse. RESULTS: WTAP was increased but ALB was diminished in OS tissues and/or cell lines. WTAP modulated ALB expression in an m6A-dependent manner. Silencing of WTAP retarded the development of OS via inhibiting cell viability, migration, invasion, and tumor growth. Knockdown of ALB exerted the opposite effects on OS progression. Additionally, ALB deficiency partially eliminated the inhibiting effects of WTAP silencing on cellular processes in OS. CONCLUSIONS: This is the first report to clarify the interaction of WTAP/m6A with ALB in OS progression. These experimental data to some extent broadened the horizons of WTAP/m6A in the development of OS.

9.
Artigo em Inglês | MEDLINE | ID: mdl-36692843

RESUMO

Two-dimensional conductive metal-organic frameworks (2D-c-MOFs) have attracted extensive attention owing to their unique structures and physical-chemical properties. However, the planarly extended structure of 2D-c-MOFs usually limited the accessibility of the active sites. Herein, we designed a triptycene-based 2D vertically conductive MOF (2D-vc-MOF) by coordinating 2,3,6,7,14,15-hexahydroxyltriptycene (HHTC) with Cu2+. The vertically extended 2D-vc-MOF(Cu) possesses a weak interlayer interaction, which leads to a facile exfoliation to the nanosheet. Compared with the classical 2D-c-MOFs with planarly extended 2D structures, 2D-vc-MOF(Cu) exhibits a 100% increased catalytic activity in terms of turnover number and a two-fold increased selectivity. Density functional theory (DFT) calculations further revealed that higher activity originated from the lower energy barriers of the vertically extended 2D structures during the CO2 reduction reaction process.

10.
J Cardiothorac Surg ; 18(1): 31, 2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36650548

RESUMO

BACKGROUND: The effect of gender on patients with mitral valve regurgitation (MR) undergoing transcatheter mitral valve repair (TMVR) remains to be defined. The aim of the present study is a comprehensive meta-analysis of studies that investigate differences between men and women after TMVR. METHODS: A systematic literature search was carried out on eight databases to collect all relevant studies on gender-related outcomes of TMVR before March 1, 2021. The main outcomes of interest were mortality, cardiac function, MR class and other complications. RESULTS: A total of eight literatures were included, all of which were retrospective observational studies. Compared to women patients, men had lower postoperative New York Heart Association (NYHA) class (OR = 1.53, 95%CI [1.23, 1.91], P = 0.0001) and higher incidence of postoperative acute kidney injury (AKI) (OR = 1.25, 95%CI [1.16, 1.34], P < 0.05). There were no significant difference on mortality in 30 days (OR = 0.95, 95%CI [0.81, 1.11], P = 0.53) and in 2 years (OR = 0.99, 95%CI [0.75, 1.30], P = 0.93), mitral valve regurgitation (MR) class (OR = 1.30, 95%CI [0.97, 1.75], P = 0.08) and incidence of myocardial infarction (MI) (OR = 0.88, 95%CI [0.65, 1.18], P = 0.38), stroke (OR = 0.80, 95%CI [0.63, 1.02], P = 0.08) and bleeding in hospital (OR = 0.84, 95%CI [0.59, 1.19], P = 0.32). CONCLUSIONS: Our meta-analysis demonstrates that men undergoing TMVR have worse preoperative diseases (diabetes mellitus, coronary artery disease, renal failure and myocardial infarction) while they have superior postoperative NYHA class at one-year. There are no significantly difference in other indexes between men and women.


Assuntos
Implante de Prótese de Valva Cardíaca , Insuficiência da Valva Mitral , Infarto do Miocárdio , Masculino , Humanos , Feminino , Valva Mitral/cirurgia , Resultado do Tratamento , Implante de Prótese de Valva Cardíaca/efeitos adversos , Estudos Retrospectivos , Cateterismo Cardíaco/efeitos adversos , Infarto do Miocárdio/etiologia
11.
Math Biosci Eng ; 20(1): 613-623, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36650781

RESUMO

In lumbar puncture surgery, compared with the conventional methodologies like computed tomography and magnetic resonance imaging, ultrasound imaging offers the advantages of being low cost, no radiation and real-time image generation. However, the use of ultrasound equipment in lumbar puncture involves a cumbersome and time-consuming process for the subjective imaging of the overall structure of the lumbar spine in order to determine the exact puncture point and path. Meanwhile, the robotic arm puncture system has the advantages of high precision, good stability and simple and efficient operation. As a result, robotic-assisted ultrasound scanning is valuable for the assessment of a puncture path in spinal tap surgery. In this pursuit, based on the official URSDK development package for a robot arm and the Transmission Control Protocol/Internet Protocol, the system proposed in the present study involves a program to control the robot arm to clamp down onto an ultrasonic probe to enable automatic scanning and acquisition of images. A three-dimensional reconstruction program based on the visualization toolkit was designed, and a lumbar spine experiment was conducted with this system. A total of 136 two-dimensional ultrasound images were collected in the lumbar spine model experiment by enhancing contrast of and denoising the original ultrasound images, and a linear interpolation algorithm was used to perform the three-dimensional reconstruction of the lumbar spine model. The reconstructed structure was defective, but the location of the spinous process gap was determined with the sagittal and coronal images. The feasibility of the system was verified by the reconstruction results, which can provide a reference for determining the puncture point and path planning in the lumbar puncture surgery.


Assuntos
Vértebras Lombares , Punção Espinal , Punção Espinal/métodos , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Ultrassonografia/métodos , Imageamento por Ressonância Magnética , Tomografia Computadorizada por Raios X
12.
J Chromatogr A ; 1690: 463787, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36652815

RESUMO

Alectinib and its metabolite, M4, have demonstrated a satisfactory clinical therapeutic effect in the treatment of anaplastic lymphoma kinase-positive advanced non-small-cell lung cancer. Due to individual differences among patients, therapeutic drug monitoring (TDM) is critical for guaranteeing appropriate clinical drug use. To realize TDM for alectinib and its metabolite, M4, a honeycomb phenol-formaldehyde resin (PFR) with excellent hydrophilic properties, abundant adsorption force, and a stable porous structure was synthesized by modifying the porogens F127 and P123. The prepared PFR was employed as an adsorbent in a simple and efficient spin-column solid-phase extraction (SPE) process. A rapid method for detecting alectinib and its metabolite M4 in urine was thereby established. The established method showed a linear range of 0.0200 µg mL-1-5.00 µg mL-1 and the recovery range of 98.8-103% for spiked urine samples, with relative standard deviations of ≤ 4.87% (n = 3). Our results proved the practicability of the proposed honeycomb-PFR spin-column SPE method in TDM for alectinib and its metabolite, M4.

13.
Stem Cells Dev ; 2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36647682

RESUMO

Cartilage is derived from the chondrogenic differentiation of stem cells, for which the regulatory mechanism has not been fully elucidated. N6-methyladenosine (m6A) mRNA methylation is the most common posttranscriptional modification in eukaryotic mRNAs and is mediated by m6A regulators. However, whether m6A regulators play roles in chondrogenic differentiation is unknown. Herein, we aim to determine the role of a main m6A reader protein, YTH N6-methyladenosine RNA binding protein 1 (YTHDF1), in chondrogenic differentiation regulation. Western blotting assays found the expression of YTHDF1 increased during chondrogenic differentiation of human bone marrow mesenchymal stem cells (hBMSCs). The results of qPCR, western blotting, immunohistochemistry and Alcian blue staining revealed that overexpression of YTHDF1 increased cartilage matrix synthesis and the expression of chondrogenic markers when hBMSCs, ATDC5 cells, or C3H10T1/2 cells were induced to undergo chondrogenesis. Conversely, chondrogenesis was clearly inhibited when YTHDF1 was knocked down in hBMSCs, ATDC5 cells, or C3H10T1/2 cells. Further RNA sequencing and molecular biology experiments found that YTHDF1 activated the Wnt/ß-catenin signaling pathway during chondrogenic differentiation. Finally, the effects of overexpression and knockdown of YTHDF1 on chondrogenic differentiation were reversed by inhibiting or activating ß-catenin activity. Therefore, we demonstrated that YTDHF1 promoted chondrogenic differentiation through activation of the Wnt/ß-catenin signaling pathway.

14.
Small ; : e2206180, 2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36650992

RESUMO

Fluorescent carbon dots are a novel type of nanomaterial. Due to their excellent optical properties, they have extensive application prospects in many fields. Studying the formation process and fluorescence mechanism of CDs will assist scientists in understanding the synthesis of CDs and guide more profound applications. Due to their conjugated structures, aromatic compounds have been continuously used to synthesize CDs, with emissions ranging from blue to NIR. There is a lack of a systematic summary of the formation process and fluorescence mechanism of aromatic precursors to form CDs. In this review, the formation process of CDs is first categorized into three main classes according to the precursor types of aromatic compounds: amines, phenols, and polycyclics. And then, the fluorescence mechanism of CDs synthesized from aromatic compounds is summarized. The challenges and prospects are proposed in the last section.

15.
ACS Omega ; 8(1): 1606-1617, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36643552

RESUMO

The permeability of coal exhibits multiscale characteristics in space and time, which is caused by the presence of micro and nanopores in coal. Water, free gas, and adsorbed gas are common engineering fluids in coal seams during gas extraction. Thus, it is of significance to study the multiscale characteristics and mechanisms of seepage-diffusion of different fluids in coal for gas extraction engineering. Experiments of seepage-diffusion for He, CH4, and water are carried out using ϕ50 × 100 mm cylindrical coal. It is found that the apparent diffusion coefficient for He, CH4, and water are not a constant but a variable that decays dynamically with time. The phenomenon is independent of fluid properties and determined only by the multiscale characteristics of pores in coal, and then a novel model of multiscale dynamic apparent diffusion that can accurately describe the full-time process of flow in various fluids is proposed. The mechanism of dynamic seepage-diffusion for different fluids in coal is elucidated based on a new proposed geometrical model of multiscale pores. At the early stage of flow, fluids first flow in or out of the largest pores outside coal, and at the later stage of flow, fluids flow in the micro and nanopores inside the coal matrix. The pore sizes through which the fluid flows decrease with time, which leads to a dynamic attenuation of the apparent diffusion-permeability with time. The initial apparent permeability K 0 for He/CH4 shows a "U"-shaped pattern of decreasing and then increasing with the decrease of gas pressure. When the gas pressure is lower than the turning point, the slip effect dominates, making the initial apparent permeability K 0 decrease with the increase of gas pressure. When the gas pressure is higher than the turning point, the effect of the pressure difference of the gas dominates, and K 0 increases with the increase of gas pressure. When water flows in multiscale pores, it occupies the space of large pores, making the homogeneity of pores increase, and the decay coefficient of apparent permeability becomes smaller. The multiscale permeability can explain the reason for the rapid attenuation of coalbed methane production in the late stage. It is of great significance for coalbed methane productivity prediction.

16.
Int J Biol Macromol ; 230: 123152, 2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36610566

RESUMO

The self-healing property based on metal-ligand physical coordination is particularly interesting in bio-hydrogel science due to its allowance for multiple local healing events to process. As the most abundant renewable green resource in nature, Gleditsia sinensis galactomannan has great potential as a starting material for functional materials. In this study, the biocompatible Gleditsia sinensis galactomannan and cellulose were firstly chemically modified and then taken as the main constituent for constructing the metal-ligand coordination through an enzyme-regulated strategy. The hydrogel could quickly gelatinize in the surrounding environment, corresponding to the violent exothermic phenomenon, and exhibit extraordinary self-healing behavior. The molecular dynamics simulation of the hydrogel confirmed the more stable coordinated configuration from Fe(III)-chelates than Fe(II)-chelates. The morphology, mechanical property, antibacterial, and cytotoxicity of the prepared hydrogel were also studied. Our results indicated that galactomannan hydrogel based on the metal-ligand networks could balance the kinetic stability and intrinsic healability through the enzyme-induced route, which provide a new perspective in the field of biomaterial applications.

17.
J Chem Inf Model ; 63(1): 354-361, 2023 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-36507851

RESUMO

Calcium-binding proteins play critical roles in various biological processes such as signal transduction, cell growth, and transcription factor regulation. Ion binding and target binding of Ca2+-binding proteins are highly related. Therefore, understanding the ion binding mechanism will benefit the relevant inhibitor design toward the Ca2+-binding proteins. The EF-hand is the typical ion binding motif in Ca2+-binding proteins. Previous studies indicate that the ion binding affinity of the EF-hand increases with the peptide length, but this mechanism has not been fully understood. Herein, using molecular dynamics simulations, thermodynamic integration calculations, and molecular mechanics Poisson-Boltzmann surface area analysis, we systematically investigated four Ca2+-binding peptides containing the EF-hand loop in site III of rabbit skeletal troponin C. These four peptides have 13, 21, 26, and 34 residues. Our simulations reproduced the observed trend that the ion binding affinity increases with the peptide length. Our results implied that the E-helix motif preceding the EF-hand loop, likely the Phe99 residue in particular, plays a significant role in this regulation. The E-helix has a significant impact on the backbone and side-chain conformations of the Asp103 residue, rigidifying important hydrogen bonds in the EF-hand and decreasing the solvent exposure of the Ca2+ ion, hence leading to more favorable Ca2+ binding in longer peptides. The present study provides molecular insights into the ion binding in the EF-hand and establishes an important step toward elucidating the responses of Ca2+-binding proteins toward the ion and target availability.


Assuntos
Simulação de Dinâmica Molecular , Troponina C , Animais , Coelhos , Troponina C/química , Cálcio/metabolismo , Estrutura Terciária de Proteína , Peptídeos/química , Sítios de Ligação , Ligação Proteica
18.
Chemosphere ; 313: 137613, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36549508

RESUMO

Nanobubble water (NBW) could improve methane production from anaerobic digestion (AD) of corn straw without secondary contamination. In this study, the effect of carbon dioxide nanobubble water (CO2-NBW) volumes (0%, 25%, 50%, 75%, 100%) on methane production from corn straw was investigated. The results showed that addition of CO2-NBW could improve methane production and promote substrate degradation in AD process. The highest cumulative methane production of 132.16 mL g-1VSadded was obtained in the 100% CO2-NBW added reactor, which was 17% higher than that in the control group. Additionally, the addition of CO2-NBW could mitigate the sharp decrease in pH by acting as a buffer. CO2-NBW could also enhance microorganism activity throughout the AD process. The electron transport system (ETS) activity was increased by 23%, while the ß-glucosidase, dehydrogenase (DHA), and coenzyme F420 activities were increased by 15%, 23%, and 11%, respectively, at optimum addition of CO2-NBW. Meanwhile, addition of CO2-NBW accelerated the production and consumption of reducing sugar and volatile fatty acids (VFAs), promoting the reduction rates of TS (Total solid) and VS (Volatile solid).


Assuntos
Reatores Biológicos , Zea mays , Anaerobiose , Dióxido de Carbono , Água , Metano , Suplementos Nutricionais , Biocombustíveis
19.
Sci Total Environ ; 864: 161157, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36574850

RESUMO

Nitrogen oxides (NOx ≡ NO + NO2) play a central role in air pollution and are targeted for emission mitigation by environmental protection agencies globally. Unique challenges for mitigation are presented by super-emitters, typically with the potential to dominate localized NOx budgets. Nevertheless, identifying super-emitters still challenges emission mitigation, while the spatial resolution of emission monitoring rises continuously. Here we develop an efficient, super-resolution (1 × 1 km2) inverse model based on year-round TROPOMI satellite observations over China. Consequently, we resolve hundreds of super-emitters in virtually every corner of China, even in remote and mountainous areas. They are attributed to individual plants or parks, mostly associated with industrial sectors, like energy, petrochemical, and iron and steel industries. State-of-the-art bottom-up emission estimates (i.e., MEICv1.3 and HTAPv2), as well as classic top-down inverse methods (e.g., a CTM coupled with the Ensemble Kalman Filter), do not adequately identify these super-emitters. Remarkably, more than one hundred super-emitters are unambiguously missed, while the establishments or discontinuations of the super-emitters potentially lead to under- or over-estimates, respectively. Moreover, evidence shows that these super-emitters generally dominate the NOx budget in a localized area (e.g., equivalent to a spatial scale of a medium-sized county). Although our dataset is incomplete nationwide due to the undetectable super-emitters on top of high pollution, our results imply that super-emitters contribute significantly to national NOx budgets and thus suggest the necessity to address the NOx budget by revisiting super-emitters on a large scale. Integrating the results we obtain here with a multi-tiered observation system can lead to identification and mitigation of anomalous NOx emissions.

20.
Environ Int ; 171: 107665, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36493611

RESUMO

BACKGROUND: Fine particulate matter (PM2.5) produced by landscape fires is thought to be more toxic than that from non-fire sources. However, the effects of "fire-sourced" PM2.5 on acute respiratory infection (ARI) are unknown. METHODS: We combined Demographic and Health Survey (DHS) data from 48 countries with gridded global estimates of PM2.5 concentrations from 2003 to 2014. The proportions of fire-sourced PM2.5 were assessed by a chemical transport model using a variety of PM2.5 source data. We tested for associations between ARI and short-term exposure to fire- and "non-fire-sourced" PM2.5 using a bidirectional case-crossover analysis. The robustness and homogeneity of the associations were examined by sensitivity analyses. We also established a nonlinear exposure-response relationship between fire- and non-fire-sourced PM2.5 and ARI using a two-dimensional spline function. RESULTS: The study included 36,432 children under 5 years who reported ARI symptoms. Each 1 µg/m3 increment of fire-sourced PM2.5 was associated with a 3.2 % (95 % confidence interval [CI] 0.2, 6.2) increment in the risk of ARI. This effect was comparable to that of each ∼5 µg/m3 increment in PM2.5 from non-fire sources (3.1 %; 95 % CI 2.4, 3.7). The association between ARI and total PM2.5 concentration was significantly mediated by the proportion of fire-sourced particles. Nonlinear analysis showed that the risk of ARI was increased by both fire- and non-fire-sourced PM2.5, but especially by the former. CONCLUSIONS: PM2.5 produced by landscape fire was more strongly associated to ARI among children under 5 years than that from non-fire sources.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Incêndios , Infecções Respiratórias , Humanos , Criança , Pré-Escolar , Material Particulado/análise , Fumaça/efeitos adversos , Estudos Cross-Over , Poluentes Atmosféricos/efeitos adversos , Poluentes Atmosféricos/análise , Países em Desenvolvimento , Infecções Respiratórias/epidemiologia , Infecções Respiratórias/etiologia , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise , Poluição do Ar/efeitos adversos , Poluição do Ar/análise
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