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1.
Nature ; 623(7987): 544-549, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37821703

RESUMEN

High Mountain Asia (HMA) has experienced a spatial imbalance in water resources in recent decades, partly because of a dipolar pattern of precipitation changes known as South Drying-North Wetting1. These changes can be influenced by both human activities and internal climate variability2,3. Although climate projections indicate a future widespread wetting trend over HMA1,4, the timing and mechanism of the transition from a dipolar to a monopolar pattern remain unknown. Here we demonstrate that the observed dipolar precipitation change in HMA during summer is primarily driven by westerly- and monsoon-associated precipitation patterns. The weakening of the Asian westerly jet, caused by the uneven emission of anthropogenic aerosols, favoured a dipolar precipitation trend from 1951 to 2020. Moreover, the phase transition of the Interdecadal Pacific Oscillation induces an out-of-phase precipitation change between the core region of the South Asian monsoon and southeastern HMA. Under medium- or high-emission scenarios, corresponding to a global warming of 0.6-1.1 °C compared with the present, the dipolar pattern is projected to shift to a monopolar wetting trend in the 2040s. This shift in precipitation patterns is mainly attributed to the intensified jet stream resulting from reduced emissions of anthropogenic aerosols. These findings underscore the importance of considering the impact of aerosol emission reduction in future social planning by policymakers.


Asunto(s)
Aire , Altitud , Clima , Lluvia , Aerosoles/análisis , Asia , Calentamiento Global , Estaciones del Año , Aire/análisis , Aire/normas , Actividades Humanas , Océano Pacífico
2.
Nature ; 607(7919): 480-485, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35859196

RESUMEN

Pyroelectricity describes the generation of electricity by temporal temperature change in polar materials1-3. When free-standing pyroelectric materials approach the 2D crystalline limit, how pyroelectricity behaves remained largely unknown. Here, using three model pyroelectric materials whose bonding characters along the out-of-plane direction vary from van der Waals (In2Se3), quasi-van der Waals (CsBiNb2O7) to ionic/covalent (ZnO), we experimentally show the dimensionality effect on pyroelectricity and the relation between lattice dynamics and pyroelectricity. We find that, for all three materials, when the thickness of free-standing sheets becomes small, their pyroelectric coefficients increase rapidly. We show that the material with chemical bonds along the out-of-plane direction exhibits the greatest dimensionality effect. Experimental observations evidence the possible influence of changed phonon dynamics in crystals with reduced thickness on their pyroelectricity. Our findings should stimulate fundamental study on pyroelectricity in ultra-thin materials and inspire technological development for potential pyroelectric applications in thermal imaging and energy harvesting.

3.
EMBO J ; 42(15): e113684, 2023 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-37366109

RESUMEN

Intracellular decay of N6 -methyladenine (m6A)-containing RNA potentially induces aberrant N6 -methyl-2'-adenine (6mdA) misincorporation into DNA. Biophysically, misincorporated 6mdA may destabilize the DNA duplex in a manner similar to bona fide methylated 6mdA DNA, thereby affecting DNA replication and transcription. Utilizing heavy stable isotope labeling and ultrasensitive UHPLC-MS/MS assay, we demonstrate that intracellular m6A-RNA decay does not generate free 6mdA species, nor lead to any misincorporated DNA 6mdA in most mammalian cell lines tested, unveiling the existence of a sanitation mechanism that prevents 6mdA misincorporation. Depletion of deaminase ADAL increases the levels of free 6mdA species, concomitant with the presence of DNA-misincorporated 6mdA resulting from intracellular RNA m6A decay, suggesting that ADAL catabolizes 6mdAMP in vivo. Furthermore, we show that the overexpression of adenylate kinase 1 (AK1) promotes 6mdA misincorporation, while AK1 knockdown diminishes 6mdA incorporation, in ADAL-deficient cells. We conclude that ADAL together with other factors (such as MTH1) contributes to 2'-deoxynucleotide pool sanitation in most cells but compromised sanitation (e.g., in NIH3T3 cells) and increased AK1 expression may facilitate aberrant 6mdA incorporation. This sanitation mechanism may provide a framework for the maintenance of the epigenetic 6mdA landscape.


Asunto(s)
Saneamiento , Espectrometría de Masas en Tándem , Animales , Ratones , Células 3T3 NIH , ADN , Adenilato Quinasa/genética , ARN , Mamíferos
4.
Nat Chem Biol ; 2024 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-39322788

RESUMEN

Sulfation is considered the most prevalent post-translational modification (PTM) on tyrosine; however, its importance is frequently undervalued due to difficulties in direct and unambiguous determination from phosphorylation. Here we present a sequence-independent strategy to directly map and quantify the tyrosine sulfation states in universal native peptides using an engineered protein nanopore. Molecular dynamics simulations and nanopore mutations reveal specific interactions between tyrosine sulfation and the engineered nanopore, dominating identification across diverse peptide sequences. We show a nanopore framework to discover tyrosine sulfation in unknown peptide fragments digested from a native protein and determine the sequence of the sulfated fragment based on current blockade enhancement induced by sulfation. Moreover, our method allows direct observation of peptide sulfation in ultra-low abundance, down to 1%, and distinguishes it from isobaric phosphorylation. This sequence-independent strategy suggests the potential of nanopore to explore specific PTMs in real-life samples and at the omics level.

5.
Nucleic Acids Res ; 51(D1): D106-D116, 2023 01 06.
Artículo en Inglés | MEDLINE | ID: mdl-36382409

RESUMEN

With advanced technologies to map RNA modifications, our understanding of them has been revolutionized, and they are seen to be far more widespread and important than previously thought. Current next-generation sequencing (NGS)-based modification profiling methods are blind to RNA modifications and thus require selective chemical treatment or antibody immunoprecipitation methods for particular modification types. They also face the problem of short read length, isoform ambiguities, biases and artifacts. Direct RNA sequencing (DRS) technologies, commercialized by Oxford Nanopore Technologies (ONT), enable the direct interrogation of any given modification present in individual transcripts and promise to address the limitations of previous NGS-based methods. Here, we present the first ONT-based database of quantitative RNA modification profiles, DirectRMDB, which includes 16 types of modification and a total of 904,712 modification sites in 25 species identified from 39 independent studies. In addition to standard functions adopted by existing databases, such as gene annotations and post-transcriptional association analysis, we provide a fresh view of RNA modifications, which enables exploration of the epitranscriptome in an isoform-specific manner. The DirectRMDB database is freely available at: http://www.rnamd.org/directRMDB/.


Asunto(s)
Secuenciación de Nucleótidos de Alto Rendimiento , Procesamiento Postranscripcional del ARN , Análisis de Secuencia de ARN , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Anotación de Secuencia Molecular , Isoformas de Proteínas , ARN/genética , Análisis de Secuencia de ARN/métodos , Bases de Datos de Ácidos Nucleicos
6.
Proc Natl Acad Sci U S A ; 119(49): e2123487119, 2022 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-36454749

RESUMEN

Hexanucleotide G4C2 repeat expansions in the C9orf72 gene are the most common genetic cause of amyotrophic lateral sclerosis and frontotemporal dementia. Dipeptide repeat proteins (DPRs) generated by translation of repeat-containing RNAs show toxic effects in vivo as well as in vitro and are key targets for therapeutic intervention. We generated human antibodies that bind DPRs with high affinity and specificity. Anti-GA antibodies engaged extra- and intra-cellular poly-GA and reduced aggregate formation in a poly-GA overexpressing human cell line. However, antibody treatment in human neuronal cultures synthesizing exogenous poly-GA resulted in the formation of large extracellular immune complexes and did not affect accumulation of intracellular poly-GA aggregates. Treatment with antibodies was also shown to directly alter the morphological and biochemical properties of poly-GA and to shift poly-GA/antibody complexes to more rapidly sedimenting ones. These alterations were not observed with poly-GP and have important implications for accurate measurement of poly-GA levels including the need to evaluate all centrifugation fractions and disrupt the interaction between treatment antibodies and poly-GA by denaturation. Targeting poly-GA and poly-GP in two mouse models expressing G4C2 repeats by systemic antibody delivery for up to 16 mo was well-tolerated and led to measurable brain penetration of antibodies. Long-term treatment with anti-GA antibodies produced improvement in an open-field movement test in aged C9orf72450 mice. However, chronic administration of anti-GA antibodies in AAV-(G4C2)149 mice was associated with increased levels of poly-GA detected by immunoassay and did not significantly reduce poly-GA aggregates or alleviate disease progression in this model.


Asunto(s)
Genes Reguladores , Poli A , Animales , Humanos , Ratones , Complejo Antígeno-Anticuerpo , Proteína C9orf72/genética , Dipéptidos , Modelos Animales de Enfermedad
7.
Lancet Oncol ; 25(10): 1288-1297, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39276785

RESUMEN

BACKGROUND: Ovarian clear cell carcinoma rarely responds to second-line chemotherapy, the recommended treatment for relapsed epithelial ovarian cancer. Here, we report the activity and safety of sintilimab in combination with bevacizumab in patients with relapsed or persistent ovarian clear cell carcinoma. METHODS: In the prospective, multicentre, single-arm, phase 2 INOVA trial, patients aged 18-75 years with histologically confirmed relapsed or persistent ovarian clear cell carcinoma were enrolled from eight tertiary hospitals in China. Eligible patients had an Eastern Cooperative Oncology Group performance status score of 0-2 and previous exposure to at least one cycle of platinum-containing chemotherapy. Enrolled patients received sintilimab (200 mg) and bevacizumab (15 mg/kg) intravenously every 3 weeks until disease progression. The primary endpoint was objective response rate assessed by independent central review based on Response Evaluation Criteria in Solid Tumours version 1.1. Eligible enrolled patients who received at least one cycle of treatment and had at least one tumour response assessment following the baseline assessment per protocol were included in the activity analysis. Patients who received at least one dose of study drug were included in the safety analysis. The study is registered with ClinicalTrials.gov (NCT04735861) and is ongoing. FINDINGS: Between April 8, 2021, and July 3, 2023, 51 patients were screened and 41 patients received at least one dose of sintilimab in combination with bevacizumab. Response evaluation was completed in 37 patients. Objective responses were observed in 15 patients (objective response rate 40·5%; 95% CI 24·8-57·9), of which five (14%) were complete responses and ten (27%) were partial responses. At data cutoff (Jan 29, 2024), the median follow-up was 16·9 months (IQR 7·5-23·4). Three (7%) patients developed grade 3 treatment-related adverse events including one patient with proteinuria, one patient with myocarditis, and one patient with rash. No treatment-related adverse events of worse than grade 3 severity were recorded. Treatment-related serious adverse events occurred in two (5%) patients including one patient with immune-related myocarditis and another with hypertension and renal dysfunction. No treatment-related deaths occurred. INTERPRETATION: Sintilimab in combination with bevacizumab showed promising anti-tumour activity and manageable safety in patients with relapsed or persistent ovarian clear cell carcinoma. Larger, randomised trials are warranted to compare this low-toxicity, chemotherapy-free combinatorial regimen with standard chemotherapy. FUNDING: National Key Technology Research and Development Program of China, National Natural Science Foundation of China, Beijing Xisike Clinical Oncology Research Foundation, and Innovent Biologics. TRANSLATION: For the Chinese translation of the abstract see Supplementary Materials section.


Asunto(s)
Anticuerpos Monoclonales Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica , Bevacizumab , Recurrencia Local de Neoplasia , Neoplasias Ováricas , Humanos , Bevacizumab/administración & dosificación , Bevacizumab/efectos adversos , Femenino , Persona de Mediana Edad , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Adulto , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/patología , Anciano , Recurrencia Local de Neoplasia/tratamiento farmacológico , Recurrencia Local de Neoplasia/patología , Anticuerpos Monoclonales Humanizados/efectos adversos , Anticuerpos Monoclonales Humanizados/uso terapéutico , Anticuerpos Monoclonales Humanizados/administración & dosificación , Estudios Prospectivos , Adenocarcinoma de Células Claras/tratamiento farmacológico , Adenocarcinoma de Células Claras/patología , Adulto Joven , Carcinoma Epitelial de Ovario/tratamiento farmacológico , Adolescente , China
8.
J Cell Mol Med ; 28(8): e18294, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38652109

RESUMEN

Forkhead box protein 1 (FOXP1) serves as a tumour promoter or suppressor depending on different cancers, but its effect in oesophageal squamous cell carcinoma has not been fully elucidated. This study investigated the role of FOXP1 in oesophageal squamous cell carcinoma through bioinformatics analysis and experimental verification. We determined through public databases that FOXP1 expresses low in oesophageal squamous cell carcinoma compared with normal tissues, while high expression of FOXP1 indicates a better prognosis. We identified potential target genes regulated by FOXP1, and explored the potential biological processes and signalling pathways involved in FOXP1 in oesophageal squamous cell carcinoma through GO and KEGG enrichment, gene co-expression analysis, and protein interaction network construction. We also analysed the correlation between FOXP1 and tumour immune infiltration levels. We further validated the inhibitory effect of FOXP1 on the proliferation of oesophageal squamous cell carcinoma cells through CCK-8, colony formation and subcutaneous tumour formation assays. This study revealed the anticarcinogenic effect of FOXP1 in oesophageal squamous cell carcinoma, which may serve as a novel biological target for the treatment of tumour.


Asunto(s)
Proliferación Celular , Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Factores de Transcripción Forkhead , Regulación Neoplásica de la Expresión Génica , Proteínas Represoras , Humanos , Factores de Transcripción Forkhead/metabolismo , Factores de Transcripción Forkhead/genética , Carcinoma de Células Escamosas de Esófago/genética , Carcinoma de Células Escamosas de Esófago/patología , Carcinoma de Células Escamosas de Esófago/metabolismo , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/patología , Línea Celular Tumoral , Animales , Proteínas Represoras/metabolismo , Proteínas Represoras/genética , Biología Computacional/métodos , Ratones , Pronóstico , Mapas de Interacción de Proteínas/genética , Transducción de Señal , Redes Reguladoras de Genes , Ratones Desnudos
9.
J Am Chem Soc ; 146(19): 13546-13557, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38690842

RESUMEN

Glycidic esters represent pivotal constituents in synthetic chemistry, offering enhanced versatility for tailoring toward a diverse array of molecular targets in comparison with simple epoxides. While considerable progress has been made in the asymmetric synthesis of trans- and trisubstituted glycidic esters, achieving enantioselective preparation of cis-glycidic esters has remained a long-standing challenge. Here, we demonstrate a selectivity-predictable modular platform for the asymmetric synthesis of cis-glycidic esters via a novel dinuclear (salen)titanium(III)-catalyzed radical-type kinetic resolution (KR) approach. This radical KR protocol operates under mild conditions and demonstrates a wide substrate scope, facilitating the synthesis of alkyl- and aryl-substituted cis-glycidic esters with high levels of regioselectivity and enantioselectivity, along with hydroxy ester byproducts representing synthetically valuable motifs as well. This study presents a unique exploration of radical-type KR applied to epoxides, effectively overcoming the steric challenges inherent in conventional nucleophilic-type methodologies typically employed in epoxide chemistry.

10.
J Am Chem Soc ; 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38584396

RESUMEN

Because of their innate chemical stability, the ubiquitous perfluoroalkyl and polyfluoroalkyl substances (PFASs) have been dubbed "forever chemicals" and have attracted considerable attention. However, their stability under environmental conditions has not been widely verified. Herein, perfluorooctanoic acid (PFOA), a widely used and detected PFAS, was found to be spontaneously degraded in aqueous microdroplets under room temperature and atmospheric pressure conditions. This unexpected fast degradation occurred via a unique multicycle redox reaction of PFOA with interfacial reactive species on the droplet surface. Similar degradation was observed for other PFASs. This study extends the current understanding of the environmental fate and chemistry of PFASs and provides insight into aid in the development of effective methods for removing PFASs.

11.
Int J Cancer ; 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38863244

RESUMEN

There is a lack of evidence from cohort studies on the causal association of long-term exposure to ambient fine particulate matter (PM2.5) and its chemical components with the risk of nasopharyngeal carcinoma (NPC) recurrence. Based on a 10-year prospective cohort of 1184 newly diagnosed NPC patients, we comprehensively evaluated the potential causal links of ambient PM2.5 and its chemical components including black carbon (BC), organic matter (OM), sulfate (SO4 2-), nitrate (NO3 -), and ammonium (NH4 +) with the recurrence risk of NPC using a marginal structural Cox model adjusted with inverse probability weighting. We observed 291 NPC patients experiencing recurrence during the 10-year follow-up and estimated a 33% increased risk of NPC recurrence (hazard ratio [HR]: 1.33, 95% confidence interval [CI]: 1.02-1.74) following each interquartile range (IQR) increase in PM2.5 exposure. Each IQR increment in BC, NH4 +, OM, NO3 -, and SO4 2- was associated with HRs of 1.36 (95%CI: 1.13-1.65), 1.35 (95%CI: 1.07-1.70), 1.33 (95%CI: 1.11-1.59), 1.32 (95%CI: 1.06-1.64), 1.31 (95%CI: 1.08-1.57). The elderly, patients with no family history of cancer, no smoking history, no drinking history, and those with severe conditions may exhibit a greater likelihood of NPC recurrence following exposure to PM2.5 and its chemical components. Additionally, the effect estimates of the five components are greater among patients who were exposed to high concentration than in the full cohort of patients. Our study provides solid evidence for a potential relationship between long-term exposure to PM2.5 and its components and the risk of NPC recurrence.

12.
Anal Chem ; 96(11): 4514-4520, 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38447135

RESUMEN

Nanoplastics have attracted much attention due to their potential hazards. However, analysis of nanoplastics remains challenging. In this study, ionic liquid-assisted cloud-point extraction (IL-assisted CPE) was developed to enrich nanoplastics in the aqueous environment and further coupled with electromagnetic heating pyrolysis mass spectrometry. The use of trace ILs improves the extraction efficiency of CPE for nanoplastics. The effects of ILs (types, contents), nanoplastic properties (type, size), and environmental factors (aging time, humic acid content) were systematically investigated to evaluate the applicability. The limits of detection of poly(methyl methacrylate) (PMMA) and polystyrene (PS) were determined to be 1.78 and 2.67 µg/L, respectively. Real environmental samples including lake water, rainwater, and influent and effluent from wastewater treatment plant were analyzed with good accuracy (79.58-116.87%) and satisfactory precision (RSD ≤ 11.99%). A possible mechanism for ILs being absorbed into the ordered surfactant micellar and generating larger micelles to synergically enclose hydrophobic nanoplastics was proposed. This work provides a simple and efficient approach to the extraction and analysis of nanoplastics in aqueous environments.

13.
Hepatology ; 77(4): 1181-1197, 2023 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-35849032

RESUMEN

BACKGROUND AND AIMS: Liver fibrosis is a chronic disease characterized by different etiological agents; dysregulated interactions between hepatocytes and HSCs contribute to this disease. ß-arrestin 1 (ARRB1) plays an important role in liver fibrosis; however, the effect of ARRB1 on the crosstalk between hepatocytes and HSCs in liver fibrosis is unknown. The aim of this study is to investigate how ARRB1 modulates hepatocyte and HSC activation during liver fibrosis. APPROACH AND RESULTS: Normal and fibrotic human liver and serum samples were obtained. CCl 4 -induced liver fibrosis and methionine-choline deficiency-induced NASH models were constructed. Primary hepatocytes and HSCs were isolated, and human hepatic LO2 and stellate LX2 cells were used. Small extracellular vesicles (EVs) were purified, and key proteins were identified. ARRB1 was up-regulated in hepatocytes and associated with autophagic blockage in liver fibrosis. ARRB1 increased the release of hepatocyte-derived small EVs by inhibiting multivesicular body lysosomal degradation and activating Rab27A, thereby activating HSCs. Proteomic analyses showed that mannan-binding lectin serine protease 1 (MASP1) was enriched in hepatocyte-derived small EVs and activated HSCs via p38 mitogen-activated protein kinase (MAPK)/activating transcription factor 2 (ATF2) signaling. ARRB1 up-regulated MASP1 expression in hepatocytes. MASP1 promoted liver fibrosis in mice. Clinically, MASP1 expression was increased in the serum and liver tissue of patients with liver fibrosis. CONCLUSIONS: ARRB1 up-regulates the release of hepatocyte-derived MASP1-enriched small EVs by regulating the autophagic-lysosomal/multivesicular body pathway and Rab27A. Hepatocyte-derived MASP1 activates HSCs to promote liver fibrogenesis through p38 MAPK/ATF2 signaling. Thus, MASP1 is a pivotal therapeutic target in liver fibrosis.


Asunto(s)
Vesículas Extracelulares , Células Estrelladas Hepáticas , Humanos , Ratones , Animales , Células Estrelladas Hepáticas/metabolismo , Proteómica , Hepatocitos/metabolismo , Cirrosis Hepática/metabolismo , Hígado/patología , Vesículas Extracelulares/metabolismo , Serina Proteasas Asociadas a la Proteína de Unión a la Manosa/efectos adversos , Serina Proteasas Asociadas a la Proteína de Unión a la Manosa/metabolismo
14.
Plant Cell Environ ; 47(4): 1141-1159, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38098148

RESUMEN

Intercropping is a widely recognised technique that contributes to agricultural sustainability. While intercropping leguminous green manure offers advantages for soil health and tea plants growth, the impact on the accumulation of theanine and soil nitrogen cycle are largely unknown. The levels of theanine, epigallocatechin gallate and soluble sugar in tea leaves increased by 52.87% and 40.98%, 22.80% and 6.17%, 22.22% and 29.04% in intercropping with soybean-Chinese milk vetch rotation and soybean alone, respectively. Additionally, intercropping significantly increased soil amino acidnitrogen content, enhanced extracellular enzyme activities, particularly ß-glucosidase and N-acetyl-glucosaminidase, as well as soil multifunctionality. Metagenomics analysis revealed that intercropping positively influenced the relative abundances of several potentially beneficial microorganisms, including Burkholderia, Mycolicibacterium and Paraburkholderia. Intercropping resulted in lower expression levels of nitrification genes, reducing soil mineral nitrogen loss and N2 O emissions. The expression of nrfA/H significantly increased in intercropping with soybean-Chinese milk vetch rotation. Structural equation model analysis demonstrated that the accumulation of theanine in tea leaves was directly influenced by the number of intercropping leguminous green manure species, soil ammonium nitrogen and amino acid nitrogen. In summary, the intercropping strategy, particularly intercropping with soybean-Chinese milk vetch rotation, could be a novel way for theanine accumulation.


Asunto(s)
Camellia sinensis , Fabaceae , Glutamatos , Fabaceae/metabolismo , Estiércol , Leguminas , Suelo/química , Camellia sinensis/metabolismo , Glycine max , , Nitrógeno/metabolismo
15.
Opt Express ; 32(9): 15645-15657, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38859210

RESUMEN

The spectral emission of laser-induced plasma in water has a broadband continuum containing ultraviolet light, which can be used as a novel light source for the degradation of organic compounds. We studied the degradation process of the organic dye Rhodamine B (RhB) using plasma light source excited by the "Laser + Fe" mode. Spectral analysis and reaction kinetics modelling were used to study the degradation mechanism. The degradation process using this light source could be divided into two stages. The initial stage was mainly photocatalytic degradation, where ultraviolet light broke the chemical bond of RhB, and then RhB was degraded by the strong oxidising ability of ·OH. As the iron and hydrogen ion concentrations increased, the synergistic effect of photocatalysis and the Fenton reaction further enhanced the degradation rate in the later stage. The plasma excited by the "Laser + Fe" mode achieved photodegradation by effectively enhancing the ultraviolet wavelength ratio of the emission spectrum and triggered the Fenton reaction to achieve rapid organic matter degradation. Our findings indicate that the participation of the Fenton reaction can increase the degradation rate by approximately 10 times. Besides, the impact of pH on degradation efficiency demonstrates that both acidic and alkaline environments have better degradation effects than neutral conditions; this is because acidic environments can enhance the Fenton reaction, while alkaline environments can provide more ·OH.

16.
Opt Lett ; 49(15): 4262-4265, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39090909

RESUMEN

Topological edge state, a unique mode for manipulating electromagnetic waves (EMs), has been extensively studied in both fundamental and applied physics. Up to now, the work on topological edge states has focused on manipulating linearly polarized waves. Here, we realize chirality-dependent topological edge states in one-dimensional photonic crystals (1DPCs) to manipulate circularly polarized waves. By introducing the magneto-electric coupling term (chirality), the degeneracy Dirac point (DP) is opened in PCs with symmetric unit cells. The topological properties of the upper and lower bands are different in the cases of left circularly polarized (LCP) and right circularly polarized (RCP) waves by calculating the Zak phase. Moreover, mapping explicitly 1D Maxwell's equations to the Dirac equation, we demonstrate that the introduction of chirality can lead to different topological properties of bandgaps for RCP and LCP waves. Based on this chirality-dependent topology, we can further realize chirality-dependent topological edge states in photonic heterostructures composed of two kinds of PCs. Finally, we propose a realistic structure for the chirality-dependent topological edge states by placing metallic helixes in host media. Our work provides a method for manipulating topological edge states for circularly polarized waves, which has a broad range of potential applications in designing optical devices including polarizers, filters, and sensors with robustness against disorder.

17.
Chemphyschem ; 25(12): e202400078, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38526528

RESUMEN

Interactions between oxygen molecules play an important role in atmospheric chemistry and hypersonic flow chemistry in atmospheric entries. Recently, high-quality ab initio potential energy surface (PES) of the quintet O4 was reported by Paukku et al. [J. Chem. Phys. 147, 034301 (2017)]. 10543 configurations were sampled and calculated at the level of MS-CASPT2/maug-cc-pVTZ with scaled external correlation. The PES was fitted to a many-body (MB) form with the many-body part described by the permutationally invariant polynomial approach (MB-PIP). In this work, the PIP-Neural Network (PIP-NN) and MB-PIP-NN methods were used to refit the PES based on the same data by Paukku et al. Three PESs were compared. It was found that the performances differ significantly in the O+O3 region as well as in the long-range region. Therefore, additional 1300 points were sampled, and the efficient compressed-state multistate pair-density functional theory (CMS-PDFT) was used to calculate the electronic structure of these 1300 points and 10543 points by Paukku et al. Then, a completely new quintet PES was fitted using the MB-PIP-NN method. Based on this PES, the quasi-classical trajectory (QCT) approach was used to reveal all possible reaction channels for hyperthermal O2-O2 collisions.

18.
Langmuir ; 40(23): 12097-12106, 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38814133

RESUMEN

Antimony sulfide (Sb2S3) has been recognized as a catalytic material for splitting water by solar energy because of its suitable narrow band gap, high absorption coefficient, and abundance of elements. However, many deep-level defects in Sb2S3 result in a significant recombination of photoexcited electron-hole pairs, weakening its photoelectrochemical performance. Here, by using a simple hydrothermal and spin-coating method, we fabricated a step-scheme heterojunction of Sb2S3/α-Fe2O3 to improve the photoelectrochemical performance of pure Sb2S3. Our Sb2S3/α-Fe2O3 photoanode has a photocurrent density of 1.18 mA/cm2 at 1.23 V vs reversible hydrogen electrode, 1.39 times higher than that of Sb2S3 (0.84 mA/cm2). In addition, our heterojunction has a lower onset potential, a higher absorbance intensity, a higher incident photon-to-current conversion efficiency, a higher applied bias photon-to-current efficiency, and a lower charge transfer resistance compared to pure Sb2S3. Based on ultraviolet photoelectron spectroscopy, we constructed a step-scheme band structure of Sb2S3/α-Fe2O3 to explain its photoelectrochemical enhancement. This work offers a promising strategy to optimize the performance of Sb2S3 photoelectrodes for solar-driven photoelectrochemical water splitting.

19.
Nutr Cancer ; 76(4): 335-344, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38379140

RESUMEN

AIM: Malnutrition is prevalent in hepatocellular carcinoma (HCC) patients, linked to poor outcomes, necessitating early intervention. This study aimed to investigate malnutrition in HCC patients, assess Nutrition Risk Screening 2002 (NRS-2002) and Patient-Generated Subjective Global Assessment (PG-SGA) vs. Global Leadership Initiative on Malnutrition (GLIM) criteria, and identify independent risk factors. METHOD: A cross-sectional retrospective study was conducted on 207 patients with HCC. Nutritional screening/assessment results and blood samples were collected within 72 h of admission. This study assessed the prevalence of malnutrition using the NRS-2002 and PG-SGA and retrospectively using the GLIM criteria. The performance of the screening tools was evaluated using kappa (K) values. Logistic regression analyses were performed to determine whether laboratory parameters were associated with malnutrition as identified by the GLIM criteria. RESULTS: Of the participants, 30.4% were at risk of malnutrition according to NRS-2002. The agreement between the NRS-2002 and GLIM criteria was substantial. The GLIM criteria and PG-SGA diagnosed malnutrition in 43 and 54.6% of the participants, respectively. Age, anemia, and ascites correlated with malnutrition in regression. CONCLUSION: The GLIM criteria, along with NRS-2002 and PG-SGA, aid in diagnosing malnutrition in HCC patients. Recognizing risk factors improves accuracy, enabling timely interventions for better outcomes.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Desnutrición , Humanos , Estado Nutricional , Carcinoma Hepatocelular/complicaciones , Carcinoma Hepatocelular/epidemiología , Prevalencia , Estudios Retrospectivos , Estudios Transversales , Liderazgo , Evaluación Nutricional , Neoplasias Hepáticas/complicaciones , Neoplasias Hepáticas/epidemiología , Desnutrición/diagnóstico , Desnutrición/epidemiología , Desnutrición/etiología , Factores de Riesgo
20.
J Theor Biol ; 581: 111739, 2024 03 21.
Artículo en Inglés | MEDLINE | ID: mdl-38280542

RESUMEN

Elucidating the mechanism of effect of phosphate (PO43-) uptake on the growth of algal cells helps understand the frequent outbreaks of algal blooms caused by eutrophication. In this study, we develop a comprehensive mathematical model that incorporates two stages of PO43- uptake and accounts for transport time delay. The model parameter values are determined by fitting experimental data of Prorocentrum donghaiense and the model is validated using experimental data of Karenia mikimotoi. The numerical results demonstrate that the model successfully captures the general characteristics of algal growth and PO43- uptake under PO43- sufficient conditions. Significantly, the experimental and mathematical findings suggest that the time delay associated with the transfer of PO43- from the surface-adsorbed PO43- (Ps) pool to the intracellular PO43- (Pi) pool may serve as a physiologically plausible mechanism leading to oscillations of algal cell quota. These results have important implications for resource managers, enabling them to predict and deepen their understanding of harmful algal blooms.


Asunto(s)
Dinoflagelados , Fosfatos , Floraciones de Algas Nocivas , Cinética , Modelos Teóricos
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