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1.
Nature ; 590(7845): 262-267, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33568822

RESUMO

Steels with sub-micrometre grain sizes usually possess high toughness and strength, which makes them promising for lightweighting technologies and energy-saving strategies. So far, the industrial fabrication of ultrafine-grained (UFG) alloys, which generally relies on the manipulation of diffusional phase transformation, has been limited to steels with austenite-to-ferrite transformation1-3. Moreover, the limited work hardening and uniform elongation of these UFG steels1,4,5 hinder their widespread application. Here we report the facile mass production of UFG structures in a typical Fe-22Mn-0.6C twinning-induced plasticity steel by minor Cu alloying and manipulation of the recrystallization process through the intragranular nanoprecipitation (within 30 seconds) of a coherent disordered Cu-rich phase. The rapid and copious nanoprecipitation not only prevents the growth of the freshly recrystallized sub-micrometre grains but also enhances the thermal stability of the obtained UFG structure through the Zener pinning mechanism6. Moreover, owing to their full coherency and disordered nature, the precipitates exhibit weak interactions with dislocations under loading. This approach enables the preparation of a fully recrystallized UFG structure with a grain size of 800 ± 400 nanometres without the introduction of detrimental lattice defects such as brittle particles and segregated boundaries. Compared with the steel to which no Cu was added, the yield strength of the UFG structure was doubled to around 710 megapascals, with a uniform ductility of 45 per cent and a tensile strength of around 2,000 megapascals. This grain-refinement concept should be extendable to other alloy systems, and the manufacturing processes can be readily applied to existing industrial production lines.

2.
Nano Lett ; 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38833276

RESUMO

Inspired by the imbalance between extrinsic and intrinsic tendon healing, this study fabricated a new biofilter scaffold with a hierarchical structure based on a melt electrowriting technique. The outer multilayered fibrous structure with connected porous characteristics provides a novel passageway for vascularization and isolates the penetration of scar fibers, which can be referred to as a biofilter process. In vitro experiments found that the porous architecture in the outer layer can effectively prevent cell infiltration, whereas the aligned fibers in the inner layer can promote cell recruitment and growth, as well as the expression of tendon-associated proteins in a simulated friction condition. It was shown in vivo that the biofilter process could promote tendon healing and reduce scar invasion. Herein, this novel strategy indicates great potential to design new biomaterials for balancing extrinsic and intrinsic healing and realizing scarless tendon healing.

3.
Philos Trans A Math Phys Eng Sci ; 382(2271): 20230094, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38522461

RESUMO

At the Royal Society meeting in 2023, we have mainly presented our lunar orbit array concept called DSL, and also briefly introduced a concept of a lunar surface array, LARAF. As the DSL concept had been presented before, in this article, we introduce the LARAF. We propose to build an array in the far side of the Moon, with a master station which handles the data collection and processing, and 20 stations with maximum baseline of 10 km. Each station consists of 12 membrane antenna units, and the stations are connected to the master station by power line and optical fibre. The array will make interferometric observation in the 0.1-50 MHz band during the lunar night, powered by regenerated fuel cells. The whole array can be carried to the lunar surface with a heavy rocket mission, and deployed with a rover in eight months. Such an array would be an important step in the long-term development of lunar-based ultralong wavelength radio astronomy. It has a sufficiently high sensitivity to observe many radio sources in the sky, though still short of the dark age fluctuations. We discuss the possible options in the power supply, data communication, deployment etc. This article is part of a discussion meeting issue 'Astronomy from the Moon: the next decades (part 2)'.

4.
Sensors (Basel) ; 24(11)2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38894151

RESUMO

Epilepsy is a common neurological disorder, and its diagnosis mainly relies on the analysis of electroencephalogram (EEG) signals. However, the raw EEG signals contain limited recognizable features, and in order to increase the recognizable features in the input of the network, the differential features of the signals, the amplitude spectrum and the phase spectrum in the frequency domain are extracted to form a two-dimensional feature vector. In order to solve the problem of recognizing multimodal features, a neural network model based on a multimodal dual-stream network is proposed, which uses a mixture of one-dimensional convolution, two-dimensional convolution and LSTM neural networks to extract the spatial features of the EEG two-dimensional vectors and the temporal features of the signals, respectively, and combines the advantages of the two networks, using the hybrid neural network to extract both the temporal and spatial features of the signals at the same time. In addition, a channel attention module was used to focus the model on features related to seizures. Finally, multiple sets of experiments were conducted on the Bonn and New Delhi data sets, and the highest accuracy rates of 99.69% and 97.5% were obtained on the test set, respectively, verifying the superiority of the proposed model in the task of epileptic seizure detection.


Assuntos
Eletroencefalografia , Epilepsia , Redes Neurais de Computação , Convulsões , Humanos , Eletroencefalografia/métodos , Epilepsia/diagnóstico , Epilepsia/fisiopatologia , Convulsões/diagnóstico , Convulsões/fisiopatologia , Processamento de Sinais Assistido por Computador , Algoritmos
5.
Philos Trans A Math Phys Eng Sci ; 379(2188): 20190566, 2021 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-33222649

RESUMO

Due to ionosphere absorption and the interference of natural and artificial radio emissions, astronomical observation from the ground becomes very difficult at the wavelengths of decametre or longer, which we shall refer to as the ultralong wavelengths. This unexplored part of the electromagnetic spectrum has the potential for great discoveries, notably in the study of cosmic dark ages and dawn, but also in heliophysics and space weather, planets and exoplanets, cosmic ray and neutrinos, pulsar and interstellar medium (ISM), extragalactic radio sources, and so on. The difficulty of the ionosphere can be overcome by space observation, and the Moon can shield the radio frequency interferences (RFIs) from the Earth. A lunar orbit array can be a practical first step to opening up the ultralong wave band. Compared with a lunar surface observatory on the far side, the lunar orbit array is simpler and more economical, as it does not need to make the risky and expensive landing, can be easily powered with solar energy, and the data can be transmitted back to the Earth when it is on the near-side part of the orbit. Here, I describe the discovering sky at the longest wavelength (DSL) project, which will consist of a mother satellite and 6-9 daughter satellites, flying on the same circular orbit around the Moon, and forming a linear interferometer array. The data are collected by the mother satellite which computes the interferometric cross-correlations (visibilities) and transmits the data back to the Earth. The whole array can be deployed on the lunar orbit with a single rocket launch. The project is under intensive study in China. This article is part of a discussion meeting issue 'Astronomy from the Moon: the next decades'.

6.
Invest New Drugs ; 38(2): 221-228, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-30887254

RESUMO

Colorectal cancer (CRC) is the most frequently encountered malignancy associated with the rectum or colon, and accumulating evidences have implicated intestinal dysbacteriosis (IDB, disruption of gut microbiome) and exosomes in the pathology of CRC. We aimed to investigate the effect of IDB on exosome secretion in a CRC xenograft mouse model. An IDB mouse model was established and was inoculated with the CRC cell line SW480 as a xenograft tumor. Tumor growth was monitored for 15 days in sham and IDB mice, after which blood was collected to assess serum exosome secretion. A novel exosome secretion inhibitor, neticonazole, was administered to IDB mice bearing CRC xenograft tumors, followed by monitoring of tumor growth and mouse survival. Western blot analysis was performed in xenograft tumors to investigate the underlying molecular mechanism. IDB promoted CRC xenograft tumor growth and exosome secretion, which could be inhibited by the exosome secretion inhibitor neticonazole. Moreover, neticonazole treatment significantly improved the survival of IDB mice with CRC xenograft tumors, likely through increasing apoptosis of CRC xenograft tumor cells. The exosome secretion inhibitor neticonazole may serve as a promising therapeutic candidate against CRC by suppressing IDB-induced CRC tumorigenesis.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Disbiose/tratamento farmacológico , Exossomos/efeitos dos fármacos , Imidazóis/uso terapêutico , Intestinos/microbiologia , Animais , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Carcinogênese/efeitos dos fármacos , Linhagem Celular Tumoral , Disbiose/complicações , Humanos , Imidazóis/farmacologia , Masculino , Camundongos Endogâmicos C57BL
7.
J Cell Biochem ; 120(4): 5268-5276, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30382596

RESUMO

Long noncoding RNAs (lncRNAs) have important functions in tumor development and progression, including colorectal cancer (CRC), but their roles are not completely understood. In this study, the roles of the lncRNA transmembrane phosphoinositide 3-phosphatase and tensin homolog 2 pseudogene 1 (TPTE2P1), previously implicated in gallbladder cancer cell migration and invasion, were evaluated in CRC. In particular, quantitative polymerase chain reaction was used to quantify TPTE2P1 levels in tumor tissues and cell lines. The association between TPTE2P1 and survival was analyzed using the online tool OncoLnc. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assays, colony formation assays, and flow cytometry were used to evaluate the effects of TPTE2P1 on viability, cell cycle progression, and apoptosis. Signaling pathway proteins were quantitated by Western blot analysis. Finally, the role of TPTE2P1 was analyzed in vivo using mouse models. TPTE2P1 levels were significantly higher in CRC tissues than in adjacent normal tissues. Higher expression was associated with a poor survival rate. The silencing of TPTE2P1 led to cell cycle arrest at the S phase and thereby inhibited cell viability. TPTE2P1 knockdown also caused cancer cell apoptosis via the activation of the apoptosis regulator (BCL2)/caspase 3 signaling cascade. In addition, the inhibition of TPTE2P1 had suppressive effects on tumors in vivo. TPTE2P1 is upregulated in CRC and plays essential roles in the regulation of cell viability in vitro and tumor formation in vivo.


Assuntos
Proliferação de Células/genética , Sobrevivência Celular/genética , Neoplasias Colorretais/genética , RNA Longo não Codificante/genética , Animais , Apoptose/genética , Caspase 3/genética , Pontos de Checagem do Ciclo Celular/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Neoplasias Colorretais/patologia , Regulação Neoplásica da Expressão Gênica/genética , Xenoenxertos , Humanos , Camundongos , Proteínas Proto-Oncogênicas c-bcl-2/genética , Transdução de Sinais/genética
8.
J Sep Sci ; 42(19): 3095-3101, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31328867

RESUMO

Phthalate esters are easily released from plastics materials and migrate into the soil and water environment, causing serious pollution and posing a great threat to the health of human beings. A novel temperature-sensitive extractant combined with liquid-liquid microextraction was developed to preconcentrate three phthalates in the water environment. To optimize the extraction efficiency for the three phthalate esters, various parameters, including polymer molecular weight, salt type, salt addition, adsorption time, desorption solvent, desorption volume, and desorption time have been studied. Under optimal conditions, limits of detection and limits of quantification were in the range of 0.007-0.120 and 0.021-0.350 µg/L, respectively. Linearities varied in the range of 5-1000 µg/L, with the correlation coefficients of 0.9867-0.9997. The preconcentration factors were in the range of 25-75. The relative recoveries of the three phthalate esters were in the range of 82.2-105.6% at the spiked levels. The relative standard deviations were in the range of 0.7-9.2% based on triplicate measurements. The results indicate that the temperature-sensitive material is a good extractant for phthalate esters in water samples.

9.
Sensors (Basel) ; 18(2)2018 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-29439495

RESUMO

This article proposes a novel active localization method based on the mixed polarization multiple signal classification (MP-MUSIC) algorithm for positioning a metal target or an insulator target in the underwater environment by using a uniform circular antenna (UCA). The boundary element method (BEM) is introduced to analyze the boundary of the target by use of a matrix equation. In this method, an electric dipole source as a part of the locating system is set perpendicularly to the plane of the UCA. As a result, the UCA can only receive the induction field of the target. The potential of each electrode of the UCA is used as spatial-temporal localization data, and it does not need to obtain the field component in each direction compared with the conventional fields-based localization method, which can be easily implemented in practical engineering applications. A simulation model and a physical experiment are constructed. The simulation and the experiment results provide accurate positioning performance, with the help of verifying the effectiveness of the proposed localization method in underwater target locating.

10.
Med Sci Monit ; 23: 452-461, 2017 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-28123172

RESUMO

BACKGROUND Tectonic family member 1 (TCTN1), a member of the tectonic family, is involved in several developmental processes and is aberrantly expressed in multiple solid tumors. However, the expression and regulation of TCTN1 in human colorectal cancer (CRC) is still not clear. MATERIAL AND METHODS The expression of TCTN1 mRNA was first explored by using Oncomine microarray datasets. TCTN1 expression was silenced in human CRC cell lines HCT116 and SW1116 via RNA interference (RNAi). Furthermore, we investigated the effect of TCTN1 depletion on CRC cell growth by MTT, colony formation, and flow cytometry in vitro. RESULTS In this study, meta-analysis showed that the expressions of TCTN1 mRNA in CRC specimens were significantly higher than that in normal specimens. Knockdown of TCTN1 expression potently inhibited the abilities of cell proliferation and colony formation as determined. Flow cytometry analysis showed that depletion of TCTN1 could cause cell cycle arrest at the G2/M phase. In addition, Annexin V/7-AAD double-staining indicated that TCTN1 silencing promoted cell apoptosis through down-regulation of caspase 3 and Bcl-2 and upregulation of cleaved caspase 3 and PARP. CONCLUSIONS Our results indicate that TCTN1 may be crucial for CRC cell growth, providing a novel alternative to target therapies of CRC. Further research on this topic is warranted.


Assuntos
Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Proteínas de Membrana/deficiência , Proteínas de Membrana/genética , Apoptose/genética , Caspase 3/metabolismo , Ciclo Celular/genética , Pontos de Checagem do Ciclo Celular/genética , Proliferação de Células/genética , Neoplasias Colorretais/metabolismo , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes/métodos , Células HCT116 , Células HEK293 , Humanos , Proteínas de Membrana/metabolismo , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , RNA Interferente Pequeno/administração & dosagem , RNA Interferente Pequeno/genética , Transfecção
11.
Sensors (Basel) ; 16(7)2016 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-27428972

RESUMO

Corrosion cracking of reinforced concrete caused by chloride salt is one of the main determinants of structure durability. Monitoring the entire process of concrete corrosion cracking is critical for assessing the remaining life of the structure and determining if maintenance is needed. Fiber Bragg Grating (FBG) sensing technology is extensively developed in photoelectric monitoring technology and has been used on many projects. FBG can detect the quasi-distribution of strain and temperature under corrosive environments, and thus it is suitable for monitoring reinforced concrete cracking. According to the mechanical principle that corrosion expansion is responsible for the reinforced concrete cracking, a package design of reinforced concrete cracking sensors based on FBG was proposed and investigated in this study. The corresponding relationship between the grating wavelength and strain was calibrated by an equal strength beam test. The effectiveness of the proposed method was verified by an electrically accelerated corrosion experiment. The fiber grating sensing technology was able to track the corrosion expansion and corrosion cracking in real time and provided data to inform decision-making for the maintenance and management of the engineering structure.

12.
Front Biosci (Landmark Ed) ; 29(7): 266, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39082354

RESUMO

BACKGROUND: Artesunate (ART) has the potential to modulate the nuclear factor kappa B (NF-κB) and Notch1/Hes1 signaling pathways, which play crucial roles in the pathogenesis of osteoporosis. This study aims to explore whether ART participates in the progression of osteoporosis by regulating these signaling pathways. METHODS: In the in vitro experiments, we treated bone marrow mesenchymal stem cells (BMSCs) with different concentrations of ART (0, 3, 6, 12 µM) and evaluated osteogenic differentiation using alkaline phosphatase staining (ALP) and alizarin red S staining (ARS) staining. The expression levels of osteocalcin (OCN), RUNT-related transcription factor 2 (RUNX2), osteoprotegerin (OPG), and receptor activator of the nuclear factor kappa ligand (RANKL) were detected by real-time quantitative PCR (RT-qPCR). The effects of ART on NF-κB p65 and Notch1 protein expression were analyzed by Western blot (WB) and immunofluorescence (IF). In the in vivo experiments, a postmenopausal osteoporosis rat model was established via ovariectomy. Bone tissue pathological injury was evaluated using hematoxylin eosin (HE) staining. Serum ALP levels were measured using a kit, bone density was determined by dual-energy X-ray absorptiometry, and serum levels of bone gla protein (BGP), OPG, RANKL, tumor necrosis factor-alpha (TNF-α), interleukin 6 (IL-6), and IL-1ß were measured by enzyme-linked immunosorbent assay (ELISA). Additionally, the expression of NF-κB p65 and Notch1 in tissues was assessed by immunohistochemistry. RESULTS: In vitro experiments revealed that compared to the control group, ART dose-dependently promoted BMSCs proliferation and enhanced their osteogenic differentiation capability. The expression of OCN, RUNX2, and OPG significantly increased in the ART-treated group, while RANKL expression decreased significantly (p < 0.05). ART significantly inhibited the expression of NF-κB p65 and Notch1/Hes1 signaling pathway proteins (p < 0.05). Compared to ART treatment alone, combined treatment with ART and phorbol myristate acetate (PMA) or valproic acid (VPA) resulted in increased expression of NF-κB p65 and Notch1 proteins and decreased osteogenic differentiation capability (p < 0.05). In vivo experiments showed that in rats treated with ART, bone damage was significantly reduced, bone density and mineral content were restored considerably, and the expression of inflammatory factors (TNF-α, IL-6, IL-1ß) decreased significantly (p < 0.05). Additionally, ART treatment significantly reduced the expression of NF-κB p65 and Notch1 proteins, increased OPG expression, and decreased BGP and RANKL levels (p < 0.05). CONCLUSION: In summary, ART facilitates the osteogenic differentiation of BMSCs by inhibiting the NF-κB and Notch1/Hes1 signaling pathways, thereby exerting significant protective effects against osteoporosis.


Assuntos
Artesunato , NF-kappa B , Osteoporose , Ovariectomia , Ratos Sprague-Dawley , Receptor Notch1 , Transdução de Sinais , Animais , Artesunato/farmacologia , Artesunato/uso terapêutico , Feminino , Transdução de Sinais/efeitos dos fármacos , Receptor Notch1/metabolismo , NF-kappa B/metabolismo , Osteoporose/metabolismo , Osteoporose/tratamento farmacológico , Osteoporose/etiologia , Ratos , Osteogênese/efeitos dos fármacos , Artemisininas/farmacologia , Artemisininas/uso terapêutico , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/efeitos dos fármacos , Inflamação/metabolismo , Diferenciação Celular/efeitos dos fármacos , Fatores de Transcrição HES-1
13.
Food Chem ; 461: 140882, 2024 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-39178548

RESUMO

In case of organic frameworks (COFs) as adsorbents in the pretreatment of complex food matrices, challenges such as poor dispersion and non-specific adsorption of interfering macromolecules like proteins are often encountered. To address this issue, this work prepared a three-dimensional covalent organic framework (3D-COF) with a novel bcu topology based on polyhedral oligomeric silsesquioxane (POSS). Subsequently, gluconolactone (GDL) was modified onto the external surface of the material via the reaction with the exposed reactive residues. The resulting POSS-COF@GDL adsorbent has an enhanced hydrophilicity in the external surface, thereby significantly improves the dispersion of materials in aqueous solution and reduces the adsorption ability toward protein. Whereas, the inner of material retains hydrophobic pores that exhibit high adsorption efficiency to small hydrophobic molecules. Compared with the traditional pretreatment methods, POSS-COF@GDL can directly extract bisphenols (BPs) in milk samples without any additional treatment. The established sample pretreatment method is coupled with high-performance liquid chromatography-ultraviolet detection (HPLC-UV), resulting in recoveries of 71.8 to 93.6%, intra- and inter-day relative standard deviations (RSDs) of <8.3%, and limits of detection (LODs) of 0.042-0.16 ng∙mL-1 for four BPs.


Assuntos
Contaminação de Alimentos , Interações Hidrofóbicas e Hidrofílicas , Leite , Compostos de Organossilício , Fenóis , Leite/química , Fenóis/química , Adsorção , Animais , Contaminação de Alimentos/análise , Compostos de Organossilício/química , Estruturas Metalorgânicas/química , Cromatografia Líquida de Alta Pressão , Compostos Benzidrílicos/química , Compostos Benzidrílicos/análise , Lactonas/química , Bovinos
14.
Clin Transl Oncol ; 2024 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-39153176

RESUMO

PURPOSE: This study aimed to develop a tumor radiomics quality and quantity model (RQQM) based on preoperative enhanced CT to predict early recurrence after radical surgery for colorectal liver metastases (CRLM). METHODS: A retrospective analysis was conducted on 282 cases from 3 centers. Clinical risk factors were examined using univariate and multivariate logistic regression (LR) to construct the clinical model. Radiomics features were extracted using the least absolute shrinkage and selection operator (LASSO) for dimensionality reduction. The LR learning algorithm was employed to construct the radiomics model, RQQM (radiomics-TBS), combined model (radiomics-clinical), clinical risk score (CRS) model and tumor burden score (TBS) model. Inter-model comparisons were made using area under the curve (AUC), decision curve analysis (DCA) and calibration curve. Log-rank tests assessed differences in disease-free survival (DFS) and overall survival (OS). RESULTS: Clinical features screening identified CRS, KRAS/NRAS/BRAF and liver lobe distribution as risk factors. Radiomics model, RQQM, combined model demonstrated higher AUC values compared to CRS and TBS model in training, internal and external validation cohorts (Delong-test P < 0.05). RQQM outperformed the radiomics model, but was slightly inferior to the combined model. Survival curves revealed statistically significant differences in 1-year DFS and 3-year OS for the RQQM (P < 0.001). CONCLUSIONS: RQQM integrates both "quality" (radiomics) and "quantity" (TBS). The radiomics model is superior to the TBS model and has a greater impact on patient prognosis. In the absence of clinical data, RQQM, relying solely on imaging data, shows an advantage in predicting early recurrence after radical surgery for CRLM.

15.
ACS Appl Mater Interfaces ; 16(35): 46145-46158, 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39180482

RESUMO

After rotator cuff injuries, uncontrolled inflammation hinders tendon-bone junction regeneration and induces scar formation in situ. Therefore, precisely controlling inflammation could be a solution to accelerate tendon-bone junction regeneration. In this study, we synthesized a peptide-metal ion complex hydrogel with thermosensitive capability that can be used as a hydrogel chemical regulator. By the coordination complex between Mg2+ and BMP-12, the free and coordinated Mg2+ can be programmability released from the hydrogel. The fast release of free Mg2+ can prevent inflammation at the early stage of injuries, according to the results of RT-qPCR and immunofluorescence staining. Then, the coordinated Mg2+ was slowly released from the hydrogel and provided an anti-inflammatory environment for tendon-bone junction regeneration in the long term. Finally, the hydrogel demonstrated enhanced therapeutic effects in a rat rotator cuff tear model. Overall, the Mg2+/BMP-12 peptide-metal ion complex-based hydrogel effectively addresses the regenerative requirements of the tendon-bone junction across various stages by graded modulating inflammation.


Assuntos
Hidrogéis , Inflamação , Peptídeos , Ratos Sprague-Dawley , Tendões , Animais , Hidrogéis/química , Hidrogéis/farmacologia , Ratos , Peptídeos/química , Peptídeos/farmacologia , Inflamação/tratamento farmacológico , Inflamação/patologia , Tendões/efeitos dos fármacos , Tendões/patologia , Magnésio/química , Magnésio/farmacologia , Regeneração/efeitos dos fármacos , Lesões do Manguito Rotador/tratamento farmacológico , Lesões do Manguito Rotador/patologia , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/patologia , Masculino , Regeneração Óssea/efeitos dos fármacos
16.
Micromachines (Basel) ; 14(11)2023 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-38004915

RESUMO

RF PAs need to be reliable enough to protect them from damage under load mismatch conditions. This paper investigated the characteristics of GaAs heterojunction bipolar transistors (HBTs) under load mismatch conditions using a novel reverse wave injection technique to realize large VSWR ruggedness measurement with the circle centered at 50 Ohm and optimal impedance separately to analyze the device in real applications. With a real-time waveform measurement system, the RF voltage and current waveform information can be acquired, which provide a more-accurate view of what is occurring at the current generator plane of the HBT device. Thereby, the potential failure mechanisms and load impedance can be identified to design the most-suitable PA circuits in communication systems.

17.
Materials (Basel) ; 16(21)2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37959476

RESUMO

Adsorption and photocatalysis are effective in removing organic pollutants from wastewater. This study is based on the memory effects of MgAl-layered double hydroxides (MgAl-LDHs) after high-temperature calcination. By introducing bismuth vanadate (BiVO4) during the reformation of the layered structure via contact with water, a composite material BiVO4/MgAl-LDHs with enhanced adsorption and visible light catalytic performance was synthesized. The effects of the calcination temperature, ratio, initial methylene blue (MB) concentration, and catalyst dosage on the adsorption and photocatalytic performance were investigated. The BiVO4/MgAl-LDHs showed better photocatalytic performance than the pure BiVO4 and MgAl-LDHs. Under the optimal conditions, the proportion of MB adsorbed in 20 min was 66.1%, and the percentage of MB degraded during 100 min of photolysis was 92.4%. The composite photocatalyst showed good chemical stability and cyclability, and the adsorption-degradation rate was 86% after four cycles. Analyses of the adsorption and photocatalytic mechanisms for the composite material showed that synergistic adsorption and visible light photocatalysis contributed to the excellent catalytic performance of the BiVO4/MgAl-LDHs. A highly adsorbent photocatalytic composite material exhibiting outstanding performance was prepared via a simple, cost-effective, and environmentally friendly method, providing reference information for the removal of organic pollutants from liquids.

18.
J Drug Target ; 31(3): 261-268, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36343203

RESUMO

The JNK pathway play a critical role in insulin resistance induced by a long-term high-sugar diet. However, the roles of up- and downstream molecules of the JNK pathway in insulin resistance are less known in vertebrates and invertebrates. As a classical organism in biological research, Drosophila melanogaster (D. melanogaster) has been widely applied to the studies of mechanism of insulin resistance. Based on previous studies, we found a novel predictive mechanism of the formation of insulin resistance in D. melanogaster. We found that JNK activated by high-sugar diet and dysregulated intestinal microbiota could mediate inflammation, and then the activated JNK released Upd3, which in turn stimulated Jak/STAT pathway to release ImpL2. ImpL2 can compete with Drosophila insulin-like peptides (Dilps) for binding with the insulin receptor and inhibit the activation of insulin pathway. In this study, we reviewed novel studies on the insulin signalling pathway based on the D. melanogaster model. The findings support our hypothesis. We, therefore, described how a long-term high-sugar diet disrupts intestinal microbiota to induce inflammation and the disruption of JNK-Jak/STAT axis. This description may offer some new clues to the formation of insulin resistance.


Assuntos
Proteínas de Drosophila , Microbioma Gastrointestinal , Resistência à Insulina , Animais , Drosophila melanogaster/metabolismo , Proteínas de Drosophila/metabolismo , Janus Quinases/metabolismo , Transdução de Sinais , Fatores de Transcrição STAT/metabolismo , Drosophila/metabolismo , Insulina/metabolismo , Inflamação , Açúcares/metabolismo , Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina/metabolismo
19.
ACS Appl Mater Interfaces ; 15(25): 30643-30652, 2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37314894

RESUMO

In this work, a boronate affinity-functionalized hierarchical mesoporous metal-organic framework adsorbent with boronate sites only in the small mesopore has been structured based on UiO-66@Fe3O4. The introduction of large mesopores in the adsorbent can promote the diffusion of small cis-diol-containing compounds (cis-diols) into small mesopore channels, and the removal of the adsorption sites on the external surface of materials and in large mesopores can enhance the size-exclusion effect of the adsorbent. In addition, the adsorbent has faster adsorption kinetics and excellent selectivity to small cis-diols. Finally, a magnetic dispersive solid-phase extraction coupled with high-performance liquid chromatography was established for the enrichment and detection of nucleotides in plasma. Four nucleotides achieve the recoveries from 93.25 to 118.79%, the limits of detection from 0.35 to 1.26 ng·mL-1, and the intra-day and inter-day relative standard deviations of less than 10.2%. In conclusion, this method can be directly used for the detection of small cis-diol targets in complex biological samples without protein precipitation prior to the extraction.


Assuntos
Estruturas Metalorgânicas , Compostos Organometálicos , Humanos , Estruturas Metalorgânicas/química , Nucleotídeos , Ácidos Bóricos , Álcoois , Extração em Fase Sólida/métodos , Adsorção , Cromatografia Líquida de Alta Pressão
20.
J Chromatogr A ; 1698: 464005, 2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37087855

RESUMO

The structure of ligands has a significant influence on the separation properties of alkyl and aromatic phases in reversed-phase liquid chromatography. Compared with alkyl phases, the effect of stereoconfiguration of aromatic ligands on the retention and selectivity of stationary phases has rarely been addressed. To illustrate the issue, three terphenyl isomer-bonded stationary phases were prepared via the coupling chemistry of isocyanate with terphenyl amine isomers, 3,4-diphenylaniline, 2,4-diphenylaniline and 4-amino-p-terphenyl, respectively. The retention behaviors of stationary phases were assessed in terms of retention strength, selectivity, hydrophobic and π-π interaction by five kinds of solutes. It is found that the selectivity towards the solutes is slightly larger on the branched m-terphenyl-bonded phase (m-π3) than o-terphenyl-bonded phase (o-π3) but is significantly improved on the chain p-terphenyl-bonded phase (p-π3). The results can be interpreted by the ease self-adjustment of the conformation of the chain p-terphenyl ligand and the smaller steric effect of p-π3 towards the insertion of solutes into the ligand brushes. In addition, the p-π3 yields excellent selective separation towards aromatic solutes. These findings are of significance in the design of aromatic stationary phases.


Assuntos
Cromatografia de Fase Reversa , Compostos de Terfenil , Ligantes , Interações Hidrofóbicas e Hidrofílicas , Aminas
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