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1.
Adv Mater ; : e2409275, 2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-39223847

RESUMEN

Environmental-friendless and high-performance thermoelectrics play a significant role in exploring sustainable clean energy. Among them, AgSbTe2 thermoelectrics, benefiting from the disorder in the cation sublattice and interface scattering from secondary phases of Ag2Te and Sb2Te3, exhibit low thermal conductivity and a maximum figure-of-merit ZT of 2.6 at 573 K via optimizing electrical properties and addressing phase transition issues. Therefore, AgSbTe2 shows considerable potential as a promising medium-temperature thermoelectric material. Additionally, with the increasing demands for device integration and portability in the information age, the research on flexible and wearable AgSbTe2 thermoelectrics aligns with contemporary development needs, leading to a growing number of research findings. This work provides a detailed and timely review of AgSbTe2-based thermoelectrics from materials to devices. Principles and performance optimization strategies are highlighted for the thermoelectric performance enhancement in AgSbTe2. The current challenges and future research directions of AgSbTe2-based thermoelectrics are pointed out. This review will guide the development of high-performance AgSbTe2-based thermoelectrics for practical applications.

2.
Nat Commun ; 15(1): 6508, 2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39095396

RESUMEN

The sluggish kinetics of Volmer step in the alkaline hydrogen evolution results in large energy consumption. The challenge that has yet well resolved is to control the water adsorption and dissociation. Here, we develop biaxially strained MoSe2 three dimensional nanoshells that exhibit enhanced catalytic performance with a low overpotential of 58.2 mV at 10 mA cm-2 in base, and long-term stable activity in membrane-electrode-assembly based electrolyser at 1 A cm-2. Compared to the flat and uniaxial-strained MoSe2, we establish that the stably adsorbed OH engineer on biaxially strained MoSe2 changes the water adsorption configuration from O-down on Mo to O-horizontal on OH* via stronger hydrogen bonds. The favorable water dissociation on 3-coordinated Mo sites and hydrogen adsorption on 4-coordinated Mo sites constitute a tandem electrolysis, resulting in thermodynamically favorable hydrogen evolution. This work deepens our understanding to the impact of strain dimensions on water dissociation and inspires the design of nanostructured catalysts for accelerating the rate-determining step in multi-electron reactions.

3.
Talanta ; 280: 126758, 2024 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-39180877

RESUMEN

DNA walkers have emerged as a powerful tool in various biosensors, enabling the detection of low-abundance analytes with their precise programmability and efficient signal amplification capacity. However, many existing approaches are hampered by limited reaction kinetics. Herein, we designed a stochastic bipedal dual-DNA walkers (SBDW) that can traverse at high speed on AuNP-based three-dimensional (3D) tracks powered by Exo III. The SBDW exhibited superior reaction kinetics and are up to least 2.25 times faster than traditional DNA walkers, reaching a plateau within 40 min. This advancement allows for rapid and highly sensitive fluorescence detection of a significant base excision repair enzyme of APE1 with a detection limit of 0.001 U/mL. In comparison to traditional DNA walkers, this platform enables highly sensitive and specific APE1 assays in cell lysate and facilitates rapid and accurate screening of APE1 inhibitors. Given its rapid, sensitive, specific, and reliable analysis features, the strategy shows great promise in drug discovery and clinical diagnosis.


Asunto(s)
ADN-(Sitio Apurínico o Apirimidínico) Liasa , ADN , Inhibidores Enzimáticos , Procesos Estocásticos , ADN-(Sitio Apurínico o Apirimidínico) Liasa/antagonistas & inhibidores , ADN-(Sitio Apurínico o Apirimidínico) Liasa/metabolismo , Humanos , ADN/química , ADN/análisis , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Técnicas Biosensibles/métodos , Oro/química , Límite de Detección , Nanopartículas del Metal/química , Exodesoxirribonucleasas/química , Exodesoxirribonucleasas/metabolismo , Cinética
4.
Anal Methods ; 16(36): 6220-6228, 2024 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-39193784

RESUMEN

In contrast to the unipedal DNA walker, a bipedal DNA walker features a broader walking area and exhibits faster walking kinetics, leading to enhanced amplification efficiency. In this study, we designed a stochastic three-dimensional (3D) bipedal DNA walker, capable of navigating AuNP-based 3D tracks, driven by exonuclease III (Exo III). This detection system enables the linear detection of the non-invasive biomarker apurinic/apyrimidinic endonuclease 1 (APE1) activity across a range of 0 to 120 U per mL, with a detection limit of 0.03 U per mL. The platform not only offers a novel DNA walker for sensitive APE1 detection in cell lysate but also facilitates the precise assessment of NCA's inhibitory effect on APE1. This research holds promise for future screening of other potential APE1 inhibitors.


Asunto(s)
ADN-(Sitio Apurínico o Apirimidínico) Liasa , ADN , ADN-(Sitio Apurínico o Apirimidínico) Liasa/metabolismo , Humanos , ADN/química , ADN/análisis , Oro/química , Límite de Detección , Nanopartículas del Metal/química , Exodesoxirribonucleasas/química , Exodesoxirribonucleasas/metabolismo , Técnicas Biosensibles/métodos
5.
J Colloid Interface Sci ; 674: 841-851, 2024 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-38955015

RESUMEN

Due to the complexity of regulatory networks of disease-related biomarkers, developing simple, sensitive, and accurate methods has remained challenging for precise diagnosis. Herein, an "AND" logic gates DNA molecular machine (LGDM) was constructed, which was powered by the catalytic hairpin assembly (CHA). It was coupled with dual-emission CdTe quantum dots (QDs)-based cation exchange reaction (CER) for label-free, sensitive, and ratiometric fluorescence detection of APE1 and miRNA biomarkers. Benefiting from synergistic signal amplification strategies and a ratiometric fluorometric output mode, this LGDM enables accurate logic computing with robust and significant output signals from weak inputs. It offers improved sensitivity and selectivity even in cell extracts. Using dual-emission spectra CdTe QDs, with a ratiometric signal output mode, ensured good stability and effectively prevented false-positive signals from intrinsic biological interferences compared to the approach relying on a single signal output mode, which enabled the LGDM to achieve rapid, efficient, and accurate natural drug screening against APE1 inhibitors in vitro and cells. The developed method provides impetus to streamline research related to miRNA and APE1, offering significant promise for widespread application in drug development and clinical analysis.


Asunto(s)
Compuestos de Cadmio , ADN-(Sitio Apurínico o Apirimidínico) Liasa , MicroARNs , Puntos Cuánticos , Telurio , Humanos , MicroARNs/análisis , MicroARNs/antagonistas & inhibidores , Telurio/química , Puntos Cuánticos/química , ADN-(Sitio Apurínico o Apirimidínico) Liasa/antagonistas & inhibidores , ADN-(Sitio Apurínico o Apirimidínico) Liasa/metabolismo , Compuestos de Cadmio/química , Espectrometría de Fluorescencia , ADN/química , Fluorescencia , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/química , Colorantes Fluorescentes/química , Evaluación Preclínica de Medicamentos , Computadores Moleculares
6.
J Nanobiotechnology ; 22(1): 433, 2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-39039601

RESUMEN

Myocardial infarction (MI) is one of the leading causes of death. This is attributed to the dramatic changes in the myocardial microenvironment post-MI. Therefore, effective intervention in the early stages of MI is significant for inhibiting its progression and improving cardiac function. Herein, an injectable composite hydrogel scaffold (Gel-pBP@Mg) was developed by integrating magnesium (Mg)-modified black phosphorus nanosheets (pBP@Mg) into a reactive oxygen species-responsive hydrogel (Gel). This loose and porous Gel provides a natural platform for carrying pBP@Mg. In situ, sustained release of pBP@Mg is achieved via responsive ROS degradation in the infarct site. The high ROS reactivity of Black phosphorus nanosheets (BPNSs) can effectively inhibit the progression of oxidative stress in the infarct area and reduce inflammatory response by down-regulating the NF-κB pathway. Additionally, the sustained release of Mg loaded on the surface of BPNSs can effectively promote angiogenesis in MI, which is significant for the long-term prognosis after infarction. Our developed Gel-pBP@Mg effectively blocked infarction progression and improved myocardial function by sustainably inhibiting the "oxidative stress-inflammation" reaction chain and pro-angiogenesis. This study reveals Gel-pBP@Mg composite therapeutic potential in treating MI through In vitro and In vivo studies, providing a promising modality for MI treatment.


Asunto(s)
Antioxidantes , Infarto del Miocardio , Estrés Oxidativo , Fósforo , Especies Reactivas de Oxígeno , Animales , Masculino , Ratones , Angiogénesis , Antioxidantes/farmacología , Antioxidantes/química , Hidrogeles/química , Magnesio/química , Magnesio/farmacología , Infarto del Miocardio/tratamiento farmacológico , Nanoestructuras/química , Neovascularización Fisiológica/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Fósforo/química , Especies Reactivas de Oxígeno/metabolismo
7.
Adv Mater ; 36(36): e2405386, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39022849

RESUMEN

While cobalt (Co) exhibits a comparable energy barrier for H* adsorption/desorption to platinum in theory, it is generally not suitable for alkaline hydrogen evolution reaction (HER) because of unfavorable water dissociation. Here, the Kirkendall effect is adopted to fabricate positive-charged hollow metal Co (PHCo) nanoshells that are stabilized by MoO2 and chainmail carbon as the electron sink. Compared to the zero-valent Co, the PHCo accelerates the water dissociation and changes the rate-determining step from Volmer to Heyrovsky process. Alkaline HER occurs with a low overpotential of 59.0 mV at 10 mA cm-2. Operando Raman and first principles calculations reveal that the interfacial water to the PHCo sites and the accelerated proton transfer are conducive to the adsorption and dissociation of H2O molecules. Meanwhile, the upshifted d-band center of PHCo optimizes the adsorption/desorption of H*. This work provides a unique synthesis of hollow Co nanoshells via the Kirkendall effect and insights to water dissociation on catalyst surfaces with tailored charge states.

8.
Biochem Pharmacol ; 226: 116370, 2024 08.
Artículo en Inglés | MEDLINE | ID: mdl-38880359

RESUMEN

Tendon injuries typically display limited reparative capacity, often resulting in suboptimal outcomes and an elevated risk of recurrence or rupture. While cytokines of the IL-6 family are primarily recognised for their inflammatory properties, they also have multifaceted roles in tissue regeneration and repair. Despite this, studies examining the association between IL-6 family cytokines and tendon repair remained scarce. gp130, a type of glycoprotein, functions as a co-receptor for all cytokines in the IL-6 family. Its role is to assist in the transmission of signals following the binding of ligands to receptors. RCGD423 is a gp130 modulator. Phosphorylation of residue Y759 of gp130 recruits SHP2 and SOCS3 and inhibits activation of the STAT3 pathway. In our study, RCGD423 stimulated the formation of homologous dimers of gp130 and the phosphorylation of Y759 residues without the involvement of IL-6 and IL-6R. Subsequently, the phosphorylated residues recruited SHP2, activating the downstream ERK and AKT pathways. These mechanisms ultimately promoted the migration ability of tenocytes and matrix synthesis, especially collagen I. Moreover, RCGD423 also demonstrated significant improvements in collagen content, alignment of collagen fibres, and biological and biomechanical function in a rat Achilles tendon injury model. In summary, we demonstrated a promising gp130 modulator (RCGD423) that could potentially enhance tendon injury repair by redirecting downstream signalling of IL-6, suggesting its potential therapeutic application for tendon injuries.


Asunto(s)
Tendón Calcáneo , Movimiento Celular , Receptor gp130 de Citocinas , Proteína Tirosina Fosfatasa no Receptora Tipo 11 , Proteínas Proto-Oncogénicas c-akt , Ratas Sprague-Dawley , Tenocitos , Animales , Proteína Tirosina Fosfatasa no Receptora Tipo 11/metabolismo , Receptor gp130 de Citocinas/metabolismo , Tendón Calcáneo/metabolismo , Tendón Calcáneo/lesiones , Tendón Calcáneo/efectos de los fármacos , Movimiento Celular/efectos de los fármacos , Movimiento Celular/fisiología , Ratas , Proteínas Proto-Oncogénicas c-akt/metabolismo , Tenocitos/metabolismo , Tenocitos/efectos de los fármacos , Tenocitos/fisiología , Colágeno/metabolismo , Transducción de Señal/efectos de los fármacos , Transducción de Señal/fisiología , Masculino , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Sistema de Señalización de MAP Quinasas/fisiología , Traumatismos de los Tendones/metabolismo , Traumatismos de los Tendones/tratamiento farmacológico
9.
Int J Nanomedicine ; 19: 6231-6252, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38915916

RESUMEN

Extracellular vesicles (EVs) are microparticles released from cells in both physiological and pathological conditions and could be used to monitor the progression of various pathological states, including neoplastic diseases. In various EVs, tumor-derived extracellular vesicles (TEVs) are secreted by different tumor cells and are abundant in many molecular components, such as proteins, nucleic acids, lipids, and carbohydrates. TEVs play a crucial role in forming and advancing various cancer processes. Therefore, TEVs are regarded as promising biomarkers for the early detection of cancer in liquid biopsy. However, the currently developed TEV detection methods still face several key scientific problems that need to be solved, such as low sensitivity, poor specificity, and poor accuracy. To overcome these limitations, DNA walkers have emerged as one of the most popular nanodevices that exhibit better signal amplification capability and enable highly sensitive and specific detection of the analytes. Due to their unique properties of high directionality, flexibility, and efficiency, DNA walkers hold great potential for detecting TEVs. This paper provides an introduction to EVs and DNA walker, additionally, it summarizes recent advances in DNA walker-based detection of TEVs (2018-2024). The review highlights the close relationship between TEVs and DNA walkers, aims to offer valuable insights into TEV detection and to inspire the development of reliable, efficient, simple, and innovative methods for detecting TEVs based on DNA walker in the future.


Asunto(s)
ADN , Vesículas Extracelulares , Neoplasias , Humanos , Vesículas Extracelulares/química , Neoplasias/metabolismo , ADN/química , Biomarcadores de Tumor , Biopsia Líquida/métodos , Detección Precoz del Cáncer/métodos
10.
Oncol Lett ; 28(1): 321, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38807679

RESUMEN

Esophagogastric junction adenocarcinoma (EJA) has increased in recent years, and it exhibits a poor prognosis and a short survival period for patients. Hydrogen sulfide (H2S) plays an important role in the pathogenesis of cancer and has been studied as a diagnostic factor in some tumor diseases. However, few studies have explored the diagnostic value of H2S for EJA. In the present study, a total of 56 patients with early-stage EJA were enrolled while 57 healthy individuals were selected as the healthy control group. Clinical features were recorded, and exhaled H2S and blood samples were collected from both groups. Exhaled H2S and serum interleukin-8 (IL-8) expression levels were detected in both groups. The correlation between exhaled H2S and serum IL-8 levels was analyzed using Pearson's correlation method. Receiver operating characteristic (ROC) curve was used to evaluate the diagnostic value of exhaled H2S combined with IL-8 detection in EJA. The results showed that patients with EJA exhaled more H2S than healthy individuals. In addition, exhaled H2S was positively correlated with increased IL-8 expression. The ROC curve revealed that the exhaled H2S test had an acceptable diagnostic effect and could be used to diagnose EJA. The increase in H2S exhaled by patients with EJA indicated that H2S may be related to the occurrence and development of EJA; however, the in vivo mechanism needs to be further explored. Collectively, it was determined in the present study that exhaled H2S was significantly higher in patients with early-stage EJA than in healthy controls and combined diagnosis with patient serum IL-8 could improve diagnostic accuracy, which has potential diagnostic value for early diagnosis and screening of EJA.

11.
Eur J Ophthalmol ; : 11206721241252476, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38693770

RESUMEN

PURPOSES: To investigate the features of the anterior segment structures in neovascular glaucoma (NVG) and analyze its differences from primary angle-closure glaucoma (PACG). METHODS: This study included patients who were first diagnosed with monocular NVG and PACG at the Affiliated Eye Hospital of Nanchang University during August 2019 to June 2022. Ultrasound biomicroscopy (UBM) was used to measure the anterior segment parameters of those eyes, including anterior chamber depth (ACD), anterior chamber width (ACW), anterior chamber area (ACA), iris area (IA), maximum iris thickness (ITMAX), middle iris thickness (ITMID), iris curvature (IC), lens vault (LV), angle opening distance (AOD500), trabecular iris angle (TIA500), trabecular-iris space area (TISA500) and peripheral anterior synechia (PAS) length. RESULTS: In this study, paired samples t-test showed that IA [1.170(0.324) mm2], ITMAX [0.368(0.079) mm], ITMID [0.280(0.062) mm] and IC [0.147(0.037) mm] of NVG were smaller than F-NVG [2.058(0.195) mm2, 0.611(0.045) mm, 0.415(0.049) mm and 0.272(0.077) mm], the AOD500, TIA500, and TISA500 of NVG were also smaller than F-NVG. Independent samples t-test showed that ACD [2.349(0.350) mm] and ACA [16.326(3.547) mm2] of NVG were larger than PACG [1.971(0.240) mm, 12.030(1.860) mm2], but the IA [1.170(0.324) mm2], ITMAX [0.368(0.079) mm], ITMID [0.280(0.062) mm], IC [0.147(0.037) mm] and LV [0.436(0.172 mm)] were smaller than PACG [1.740(0.294) mm2, 0.548(0.084) mm, 0.404(0.065) mm, 0.283(0.060) mm and 0.737(0.196) mm]. Among the 16 patients with 360° angle-closure NVG, the PAS length was 0.834 (0.326) mm, which exceeded the Schwalbe line. CONCLUSION: In NVG, the iris is atrophied, thinned, and straight, while the ACD is normal or slightly shallow. In 360° angle-closure NVG, the PAS length exceeds the Schwalbe line, presenting a pseudo angle phenomenon and a hockey stick sign. Notably, the anterior segment structure morphology of NVG exhibit differences from those of PACG.

12.
Small ; 20(35): e2402726, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38651509

RESUMEN

Heterogeneous catalysts have attracted extensive attention among various emerging catalysts for their exceptional oxygen evolution reaction (OER) capabilities, outperforming their single-component counterparts. Nonetheless, the synthesis of heterogeneous materials with predictable, precise, and facile control remains a formidable challenge. Herein, a novel strategy involving the decoration of catalysts with CeO2 is introduced to concurrently engineer heterogeneous interfaces and adjust phase composition, thereby enhancing OER performance. Theoretical calculations suggest that the presence of ceria reduces the free energy barrier for the conversion of nitrides into metals. Supporting this, the experimental findings reveal that the incorporation of rare earth oxides enables the controlled phase transition from nitride into metal, with the proportion adjustable by varying the amount of added rare earth. Thanks to the role of CeO2 decoration in promoting the reaction kinetics and fostering the formation of the genuine active phase, the optimized Ni3FeN/Ni3Fe/CeO2-5% nanoparticles heterostructure catalyst exhibits outstanding OER activity, achieving an overpotential of just 249 mV at 10 mA cm-2. This approach offers fresh perspectives for the conception of highly efficient heterogeneous OER catalysts, contributing a strategic avenue for advanced catalytic design in the field of energy conversion.

13.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 41(2): 228-236, 2024 Apr 25.
Artículo en Chino | MEDLINE | ID: mdl-38686402

RESUMEN

Conventional maximum intensity projection (MIP) images tend to ignore some morphological features in the detection of intracranial aneurysms, resulting in missed detection and misdetection. To solve this problem, a new method for intracranial aneurysm detection based on omni-directional MIP image is proposed in this paper. Firstly, the three-dimensional magnetic resonance angiography (MRA) images were projected with the maximum density in all directions to obtain the MIP images. Then, the region of intracranial aneurysm was prepositioned by matching filter. Finally, the Squeeze and Excitation (SE) module was used to improve the CaraNet model. Excitation and the improved model were used to detect the predetermined location in the omni-directional MIP image to determine whether there was intracranial aneurysm. In this paper, 245 cases of images were collected to test the proposed method. The results showed that the accuracy and specificity of the proposed method could reach 93.75% and 93.86%, respectively, significantly improved the detection performance of intracranial aneurysms in MIP images.


Asunto(s)
Algoritmos , Imagenología Tridimensional , Aneurisma Intracraneal , Angiografía por Resonancia Magnética , Aneurisma Intracraneal/diagnóstico por imagen , Humanos , Angiografía por Resonancia Magnética/métodos , Imagenología Tridimensional/métodos , Sensibilidad y Especificidad , Procesamiento de Imagen Asistido por Computador/métodos
14.
RSC Adv ; 14(11): 7430-7439, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38433944

RESUMEN

Hydrotalcite intercalated nanohybrid has served as a vital phosphorescent photosensitizer owing to remarkable 1O2 quantum yield and high cell mortality performance. However, it is rather difficult for potential large or complex guest phosphors to directly intercalate into the hydrotalcite gallery. Hence, it is necessary to regulate the interlayer microenvironment of hydrotalcites firstly for outstanding photosensitive properties. Herein, two isomers, 5,5'BDA and 4,4'BDA, with distinctive dual coordinative features were selected to modify the layer microenvironment of the LGdH gallery and induce the introduction of prospective Gd(HPhN)3 phosphorescent complexes into hydrotalcite through two different coordination effects successively. A LGdH-BDA-Gd(HPhN)3 intercalated nanohybrid phosphorescent photosensitizer was successfully obtained. The results indicated that the more efficient improvement was observed from 5,5'BDA due to offering a more spacious and stable space. Specifically, LGdH-5,5'BDA-Gd(HPhN)3 showed significantly better room temperature phosphorescence properties than LGdH-4,4'BDA-Gd(HPhN)3, whose lifetime was nearly 15 times longer than the latter. Additionally, the LGdH-5,5'BDA-Gd(HPhN)3 system displayed superior singlet oxygen generation in vitro under 460 nm irradiation (the quantum yield Φ = 0.48) and outstanding photodynamic therapy performance in tumor cells. LGdH presented more remarkable enhancement performance on the RTP properties of the luminescent molecules. This work provides a novel platform for designing a high-performance hydrotalcite intercalated nanohybrid phosphorescent photosensitizer through coordination induction to regulate the layer microenvironment.

15.
Int J Nanomedicine ; 19: 1923-1949, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38435755

RESUMEN

Exosomes, small extracellular vesicles derived from cells, are known to carry important bioactive molecules such as proteins, nucleic acids, and lipids. These bioactive components play crucial roles in cell signaling, immune response, and tumor metastasis, making exosomes potential diagnostic biomarkers for various diseases. However, current methods for detecting tumor exosomes face scientific challenges including low sensitivity, poor specificity, complicated procedures, and high costs. It is essential to surmount these obstacles to enhance the precision and dependability of diagnostics that rely on exosomes. Merging DNA signal amplification techniques with the signal boosting capabilities of nanomaterials presents an encouraging strategy to overcome these constraints and improve exosome detection. This article highlights the use of DNA signal amplification technology and nanomaterials' signal enhancement effect to improve the detection of exosomes. This review seeks to offer valuable perspectives for the enhancement of amplification methods applied in practical cancer diagnosis and prognosis by providing an overview of how these novel technologies are utilized in exosome-based diagnostic procedures.


Asunto(s)
Exosomas , Vesículas Extracelulares , Neoplasias , Humanos , Neoplasias/diagnóstico , Biomarcadores , ADN
16.
Environ Res ; 249: 118438, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38350546

RESUMEN

Air pollution constitutes a substantial peril to human health, thereby catalyzing the evolution of an array of air quality prediction models. These models span from mechanistic and statistical strategies to machine learning methodologies. The burgeoning field of deep learning has given rise to a plethora of advanced models, which have demonstrated commendable performance. However, previous investigations have overlooked the salience of quantifying prediction uncertainties and potential future interconnections among air monitoring stations. Moreover, prior research typically utilized static predetermined spatial relationships, neglecting dynamic dependencies. To address these limitations, we propose a model named Dynamic Spatial-Temporal Denoising Diffusion Probabilistic Model (DST-DDPM) for air quality prediction. Our model is underpinned by the renowned denoising diffusion model, aiding us in discerning indeterminacy. In order to encapsulate dynamic patterns, we design a dynamic context encoder to generate dynamic adjacency matrices, whilst maintaining static spatial information. Furthermore, we incorporate a spatial-temporal denoising model to concurrently learn both spatial and temporal dependencies. Authenticating our model's performance using a real-world dataset collected in Beijing, the outcomes indicate that our model eclipses other baseline models in terms of both short-term and long-term predictions by 1.36% and 11.62% respectively. Finally, we conduct a case study to exhibit our model's capacity to quantify uncertainties.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Monitoreo del Ambiente , Predicción , Modelos Estadísticos , Incertidumbre , Contaminación del Aire/análisis , Monitoreo del Ambiente/métodos , Contaminantes Atmosféricos/análisis , Predicción/métodos , Análisis Espacio-Temporal , Beijing , Material Particulado/análisis
17.
Sci Rep ; 13(1): 22233, 2023 12 14.
Artículo en Inglés | MEDLINE | ID: mdl-38097677

RESUMEN

The indiscriminate use of nitrogen fertiliser (NF) is a obstruction to improve soil quality and crop yields. However, the effect of biochar and NF on soil microbial ecosystem (SME) and crop yields is unknown. A five-year field experiment in China aimed to evaluate the effects of biochar and nitrogen fertiliser (NF) combination on soil structure, C-to-N ratio (CNR), microbial biomass, and spring maize yield. Biochar and NF were applied at different rates, and the combined application resulted in a soil solid-liquid-gas ratio closer to the ideal value. The use of biochar alone and in combination with NF significantly increased soil's C, N, and CNR. A moderate application of biochar and NF resulted in favourable biological and chemical properties of the soil. The application of biochar and NF at moderate levels led to an increase in SME, with the B8N150 producing the highest yield. The highest yield of B8N150 represents a 24.25% increase compared to the unfertilized control and a 9.04% increase compared to B0N150. Moderate use of biochar and NF could be beneficial in areas with similar climatic conditions.


Asunto(s)
Carbono , Suelo , Carbono/química , Suelo/química , Fertilizantes , Ecosistema , Nitrógeno/análisis , Carbón Orgánico/química , Agricultura/métodos
18.
Cell Rep ; 42(10): 113270, 2023 10 31.
Artículo en Inglés | MEDLINE | ID: mdl-37851572

RESUMEN

Esophageal squamous-cell carcinoma (ESCC) is commonly treated with radiotherapy; however, radioresistance hinders its clinical effectiveness, and the underlying mechanism remains elusive. Here, we develop patient-derived xenografts (PDXs) from 19 patients with ESCC to investigate the mechanisms driving radioresistance. Using RNA sequencing, cytokine arrays, and single-cell RNA sequencing, we reveal an enrichment of cancer-associated fibroblast (CAF)-derived collagen type 1 (Col1) and tumor-cell-derived CXCL1 in non-responsive PDXs. Col1 not only promotes radioresistance by augmenting DNA repair capacity but also induces CXCL1 secretion in tumor cells. Additionally, CXCL1 further activates CAFs via the CXCR2-STAT3 pathway, establishing a positive feedback loop. Directly interfering with tumor-cell-derived CXCL1 or inhibiting the CXCL1-CXCR2 pathway effectively restores the radiosensitivity of radioresistant xenografts in vivo. Collectively, our study provides a comprehensive understanding of the molecular mechanisms underlying radioresistance and identifies potential targets to improve the efficacy of radiotherapy for ESCC.


Asunto(s)
Fibroblastos Asociados al Cáncer , Carcinoma de Células Escamosas , Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Tolerancia a Radiación , Humanos , Fibroblastos Asociados al Cáncer/metabolismo , Fibroblastos Asociados al Cáncer/efectos de la radiación , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/radioterapia , Carcinoma de Células Escamosas/metabolismo , Línea Celular Tumoral , Quimiocina CXCL1/metabolismo , Colágeno/metabolismo , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/radioterapia , Neoplasias Esofágicas/metabolismo , Carcinoma de Células Escamosas de Esófago/radioterapia , Carcinoma de Células Escamosas de Esófago/genética , Carcinoma de Células Escamosas de Esófago/metabolismo
19.
Angew Chem Int Ed Engl ; 62(26): e202302986, 2023 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-37186344

RESUMEN

Solid solution-oxide heterostructures combine the advantages of solid solution and heterojunction materials to improve electronic structure and optical properties by metal doping, and enhance charge separation and transfer in semiconductor photocatalysts by creating a built-in electric field. Nevertheless, the effective design and synthesis of these materials remains a significant challenge. Here, we develop a generally applicable strategy that leverages the transformable properties of metal-organic frameworks (MOFs) to prepare solid solution-oxide heterojunctions with controllable structural and chemical compositions. The process consists of three main steps. First, MOFs with different topological structures and metal centers are transformed, accompanied by pre-nucleation of a metal oxide. Second, solid solution is prepared through calcination of the transformed MOFs. Finally, a heterojunction is formed by combining solid solution with another metal oxide group through endogenous overflow. DFT calculations and study on carrier dynamics show that the structure of the material effectively prevents electrons from returning to the bulk phase, exhibiting superior photocatalytic reduction performance of CO2 . This study is expected to promote the controllable synthesis and research of MOF-derived heterojunctions.


Asunto(s)
Estructuras Metalorgánicas , Teoría Funcional de la Densidad , Electricidad , Electrónica , Óxidos
20.
3D Print Addit Manuf ; 10(2): 289-297, 2023 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-37123522

RESUMEN

Three-dimensional printing (3DP) is considered to be one of the important technologies for a new manufacturing mode. When ceramsite sand is used as a 3DP material to produce a mold (core), the printed layer is prone to deviation from the original location. In this study, the continuous stacking of the printed part deviation was termed as pushing dislocation, and a physical model was designed to investigate the pushing dislocation mechanism. When the gravity of the printing layer and the pressure of the sand scraper decreased, or when the supporting force increased, the angle of the sand scraper and the maximum friction of the prelaying layer on the printed part will reduce the pushing dislocation. To optimize the quality of the ceramsite sand mold, experiments on the pushing dislocation were conducted by altering the recoater speed, layer thickness, and bottom support condition (with or without bottom supporting plate). The sample dimensions were obtained by a 3D imaging scanner, and the gas evolution and ignition loss were measured. The results revealed that the dimensional difference of samples continuously decreased and the pushing dislocation was gradually reduced as the recoater speed and layer thickness increased. The pushing dislocation of the X-direction sample was more severe compared with that of the Y-direction sample. Increasing the layer thickness is an effective way of reducing the pushing dislocation. The bottom supporting plate can reduce the pushing dislocation, but the effect was insignificant.

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