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1.
Biophys J ; 123(10): 1253-1263, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38615193

RESUMEN

Disordered proteins are conformationally flexible proteins that are biologically important and have been implicated in devastating diseases such as Alzheimer's disease and cancer. Unlike stably folded structured proteins, disordered proteins sample a range of different conformations that needs to be accounted for. Here, we treat disordered proteins as polymer chains, and compute a dimensionless quantity called instantaneous shape ratio (Rs), as Rs = Ree2/Rg2, where Ree is end-to-end distance and Rg is radius of gyration. Extended protein conformations tend to have high Ree compared with Rg, and thus have high Rs values, whereas compact conformations have smaller Rs values. We use a scatter plot of Rs (representing shape) against Rg (representing size) as a simple map of conformational landscapes. We first examine the conformational landscape of simple polymer models such as Random Walk, Self-Avoiding Walk, and Gaussian Walk (GW), and we notice that all protein/polymer maps lie within the boundaries of the GW map. We thus use the GW map as a reference and, to assess conformational diversity, we compute the fraction of the GW conformations (fC) covered by each protein/polymer. Disordered proteins all have high fC scores, consistent with their disordered nature. Each disordered protein accesses a different region of the reference map, revealing differences in their conformational ensembles. We additionally examine the conformational maps of the nonviral gene delivery vector polyethyleneimine at various protonation states, and find that they resemble disordered proteins, with coverage of the reference map decreasing with increasing protonation state, indicating decreasing conformational diversity. We propose that our method of combining Rs and Rg in a scatter plot generates a simple, meaningful map of the conformational landscape of a disordered protein, which in turn can be used to assess conformational diversity of disordered proteins.


Asunto(s)
Proteínas Intrínsecamente Desordenadas , Conformación Proteica , Proteínas Intrínsecamente Desordenadas/química , Modelos Moleculares , Polímeros/química
2.
Environ Res ; 243: 117877, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38070855

RESUMEN

In order to reduce the particulate matter pollution to human health in producing environments, series of polyethylene terephthalate/polyvinyl alcohol (PET/PVA) based nanofibrous membranes were fabricated and investigated the dust collection and antibacterial activity. Silver nanoparticles (AgNPs), berberine (Ber) and titanium oxide nanoparticles (TiO2NPs) were selected as antibacterial agents. These novel membranes were well-characterized using SEM, FTIR, TG, etc. techniques. Results of the dust filtration showed that PET/PVA/Ag membrane had the best filtration efficiency of 99.87% for sodium chloride (NaCl) and 99.89% for dioctyl sebacate (DEHS), held low pressure drop of 160.1 Pa for NaCl and 165.3 Pa for DEHS, and posed a high tensile strength of 4.91 MPa. The bacteriostasis studies exhibited that PET/PVA/TiO2 and PET/PVA/Ag membrane showed the highest bacteriological effect on Escherichia coli (98.7%) and Staphylococcus aureus (95.9%), respectively. Meanwhile, in vitro cytotoxicity test indicated no potential cytotoxicity existed in the cell culture process of these two antibacterial membranes. Moreover, the charge distribution in the nanofibers was increased by these antibacterial agents to improve the filtration performance. The dust filtration process synergistically promoted with the antibacterial process in the antibacterial membranes. It was expected that these membranes could be efficient filter medias with broad application prospects in the field of individual protection.


Asunto(s)
Nanopartículas del Metal , Nanofibras , Humanos , Antibacterianos/farmacología , Plata/farmacología , Nanofibras/toxicidad , Nanopartículas del Metal/toxicidad , Cloruro de Sodio/farmacología , Escherichia coli , Polvo
3.
J Chem Phys ; 160(14)2024 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-38591683

RESUMEN

The plasmonic coupling between silver (Ag) and gold (Au) nanoparticles (NPs) under four polarization modes was examined: a longitudinal mode (L-mode), where the electric field of a linearly polarized incident light parallels the dimer axis, and three transverse modes (T-modes), where the electric field of the light is perpendicular to the dimer axis. The coupling was studied using the discrete dipole approximation followed by an in-house postprocessing code that determines the extinction (Qext), absorption (Qabs), and near-field (Qnf) spectra from the individual NPs as well as the whole system. In agreement with the literature results, the extinction/absorption spectra of the whole dimer have two peaks, one near the Ag localized surface plasmon resonance (LSPR) region and the other at the Au LSPR region, with the peak at Ag LSPR being reduced in all modes and the peak at Au LSPR being red-shifted and increased in the L-mode but not in the T-modes. It is further shown that the scattering at the Ag LSPR region is reduced and becomes less than the isolated Ag NPs, but the absorption at the Ag LSPR is increased and becomes greater than the isolated Ag NPs for the 50 nm Ag-Au heterodimer. This suggests that the scattering from Ag NPs is being reabsorbed by the neighboring Au NPs due to the interband electronic transition in Au at that wavelength range. The Qext from the individual NP in the heterodimer shows the presence of the Fano profile on the Au NP but not on the Ag NP. This phenomenon was further investigated by using a dielectric particle (DP) placed near the Ag or Au NPs. The Fano profile appears in the absorbing DP spectra placed near either Ag or Au NPs. However, the Fano profile is masked upon further increases in the refractive index value of the DP particle. This explains the absence of a Fano profile on the Ag NPs in the Ag-Au heterodimer. The large near-field enhancement on both Ag and Au NPs at the Au plasmonic wavelength in the L-mode for large NPs was investigated through a DP-Au system. The large enhancement was shown to arise from a large imaginary component of the DP refractive index and a small real component. Through examination of both the near- and far-field properties of the individual NPs as well as the whole system and examinations of DP-Ag and DP-Au systems, our study provides a new understanding of the couplings between Ag and Au NPs.

4.
Int J Mol Sci ; 25(7)2024 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-38612594

RESUMEN

Members of the abscisic acid (ABA)-responsive element (ABRE) binding factor (ABF) and ABA-responsive element binding protein (AREB) families play essential roles in the regulation of ABA signaling pathway activity and shape the ability of plants to adapt to a range of stressful environmental conditions. To date, however, systematic genome-wide analyses focused on the ABF/AREB gene family in wheat are lacking. Here, we identified 35 ABF/AREB genes in the wheat genome, designated TaABF1-TaABF35 according to their chromosomal distribution. These genes were further classified, based on their phylogenetic relationships, into three groups (A-C), with the TaABF genes in a given group exhibiting similar motifs and similar numbers of introns/exons. Cis-element analyses of the promoter regions upstream of these TaABFs revealed large numbers of ABREs, with the other predominant elements that were identified differing across these three groups. Patterns of TaABF gene expansion were primarily characterized by allopolyploidization and fragment duplication, with purifying selection having played a significant role in the evolution of this gene family. Further expression profiling indicated that the majority of the TaABF genes from groups A and B were highly expressed in various tissues and upregulated following abiotic stress exposure such as drought, low temperature, low nitrogen, etc., while some of the TaABF genes in group C were specifically expressed in grain tissues. Regulatory network analyses revealed that four of the group A TaABFs (TaABF2, TaABF7, TaABF13, and TaABF19) were centrally located in protein-protein interaction networks, with 13 of these TaABF genes being regulated by 11 known miRNAs, which play important roles in abiotic stress resistance such as drought and salt stress. The two primary upstream transcription factor types found to regulate TaABF gene expression were BBR/BPC and ERF, which have previously been reported to be important in the context of plant abiotic stress responses. Together, these results offer insight into the role that the ABF/AREB genes play in the responses of wheat to abiotic stressors, providing a robust foundation for future functional studies of these genes.


Asunto(s)
Estudio de Asociación del Genoma Completo , Triticum , Triticum/genética , Filogenia , Regulación de la Expresión Génica , Factores Estimuladores hacia 5'
5.
Int J Mol Sci ; 25(4)2024 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-38396749

RESUMEN

Tube-like outgrowths from root epidermal cells, known as root hairs, enhance water and nutrient absorption, facilitate microbial interactions, and contribute to plant anchorage by expanding the root surface area. Genetically regulated and strongly influenced by environmental conditions, longer root hairs generally enhance water and nutrient absorption, correlating with increased stress resistance. Wheat, a globally predominant crop pivotal for human nutrition, necessitates the identification of long root hair genotypes and their regulatory genes to enhance nutrient capture and yield potential. This study focused on 261 wheat samples of diverse genotypes during germination, revealing noticeable disparities in the length of the root hair among the genotypes. Notably, two long root hair genotypes (W106 and W136) and two short root hair genotypes (W90 and W100) were identified. Transcriptome sequencing resulted in the development of 12 root cDNA libraries, unveiling 1180 shared differentially expressed genes (DEGs). Further analyses, including GO function annotation, KEGG enrichment, MapMan metabolic pathway analysis, and protein-protein interaction (PPI) network prediction, underscored the upregulation of root hair length regulatory genes in the long root hair genotypes. These included genes are associated with GA and BA hormone signaling pathways, FRS/FRF and bHLH transcription factors, phenylpropanoid, lignin, lignan secondary metabolic pathways, the peroxidase gene for maintaining ROS steady state, and the ankyrin gene with diverse biological functions. This study contributes valuable insights into modulating the length of wheat root hair and identifies candidate genes for the genetic improvement of wheat root traits.


Asunto(s)
Transcriptoma , Triticum , Humanos , Perfilación de la Expresión Génica , Fenotipo , Agua , Regulación de la Expresión Génica de las Plantas , Raíces de Plantas/genética
6.
Opt Express ; 31(15): 25220-25229, 2023 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-37475332

RESUMEN

Hot-electron photodetection is attracting increasing interests. Based on internal photoemission mechanism, hot-electron photodetectors (HE PDs) convert incident photon energy into measurable photocurrent. To obtain polarity-switchable photocurrent, one often applies electric bias to reverse the hot-electron flow. However, the employment of bias reduces the device flexibility and increasing the bias voltage degrades the detectivity of the device. Herein, we design a planar HE PD with the polarity-switchable photocurrent controlled by the working wavelength. Optical simulations show that the device exhibits two absorption peaks due to the resonances of two Tamm plasmons (TPs). Electrical calculations predict two corresponding TP-assisted responsivity peaks, but with opposite photocurrent polarities, which are determined by the hot-electron flows with opposite directions. We find that the hot-electron flows are closely related with the population differences of TP-induced hot electrons in two electrodes. We further demonstrate that the photocurrent polarity of the HE PD can be switched by altering working wavelength from one TP wavelength to the other. We believe that this approach paves a route to achieve flexible hot-electron photodetection for extensive applications.

7.
BMC Infect Dis ; 23(1): 545, 2023 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-37605134

RESUMEN

BACKGROUND: We aimed to investigate the clinical characteristics of severe influenza virus-associated pneumonia complicated with bacterial infection in children. METHODS: We retrospectively analysed data concerning 64 paediatric patients with severe influenza virus-associated pneumonia who had been treated at our hospital. The patients were divided into observation (44 patients) and control (20 patients) groups, based on the presence or absence of concomitant bacterial infection, and clinical data were compared between the groups. RESULTS: The mean age in the observation group was 2.71 ± 1.44 years, 42 (95.45%) were aged ≤ 5 years, and 18 (40.9%) had underlying diseases. The mean age in the control group was 4.05 ± 2.21 years, 13 (65%) were aged ≤ 5 years, and 3 (15%) had underlying diseases. There was a statistically significant difference in patient age and the proportion of patients with underlying diseases (P < 0.05). The observation group had higher duration of fever values, a higher number of patients with duration of fever ≥ 7 days, a higher incidence of gasping, and a higher incidence of seizures/consciousness disturbance, and the differences were statistically significant (P < 0.05). Secondary bacterial infections in the observation group were mainly due to gram-negative bacteria, with Haemophilus influenzae and Moraxella catarrhalis being the most common pathogens. The observation group had a higher proportion of patients treated in the paediatric intensive care unit and a longer hospital stay, and the differences were statistically significant (P < 0.05). CONCLUSION: Severe influenza virus-associated pneumonia complicated with bacterial infection was more common in children aged ≤ 5 years. Younger patients with underlying diseases were more susceptible to bacterial infection (mainly due to gram-negative bacteria). The timely administration of neuraminidase inhibitors and antibiotics against susceptible bacteria is likely to help improve cure rates.


Asunto(s)
Infecciones Bacterianas , Coinfección , Gripe Humana , Orthomyxoviridae , Humanos , Niño , Lactante , Preescolar , Estudios Retrospectivos , Infecciones Bacterianas/complicaciones , Infecciones Bacterianas/epidemiología , Antibacterianos/uso terapéutico , Antivirales , Coinfección/epidemiología , Gripe Humana/complicaciones
8.
Environ Res ; 226: 115699, 2023 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-36933635

RESUMEN

Pneumoconiosis in mines occupied more than 90% of the total number of occupational diseases, poses tremendous pressure and challenges on the development of personal protection materials with high dust filtration efficiency and long-lasting comfortable wearing. In this study, a kind of polyethylene terephthalate (PET) based filter media with the bead-on-string structure and hydrophobic/oleophobic property was designed and fabricated by electrospinning technology. Nanoscale silicon dioxide (SiO2NPs) and fluorinated polyurethane (PU) used in this work were benefited for the microstructure, surface energy and hydrophobic/oleophobic property, respectively. The morphology and composition of the membranes were conducted by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and fourier transform infrared spectroscopy (FTIR). Furthermore, the filtration performance, pressure drop, moisture permeability and breathing comfortable performance were measured for the study of personal protection of dust. The results showed that at the air flow of 85 L min-1, PET/SiO2/FPU double-layer nanofibrous membrane showed high filtration efficiency and low pressure drop with the filtration efficiency of 99.96%, pressure drop of 142.5 Pa and quality factor of 0.055 Pa-1, respectively. A long term of 24 h water vapor test had proved that this membrane held an outstanding moisture permeability ability of 5296.325 g (m2 24 h)-1. Compared with the commercial 3701CN filter media, the advantages of the regular breathing frequency and strong heart rate control ability indicated that this PET/SiO2/FPU double-layer membrane had the better wearing comfortable performance with broad application prospects in the personal protection of dust in mines.


Asunto(s)
Polvo , Nanofibras , Dióxido de Silicio , Filtración/métodos , Interacciones Hidrofóbicas e Hidrofílicas
9.
Environ Res ; 221: 115218, 2023 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-36608761

RESUMEN

The regulation of bacterial quorum sensing (QS) has been used to inhibit biofouling in wastewater treatment plants and the formation of biofilms. In contrast to traditional QS regulation strategies, this study aimed to obstruct the transmembrane transport process of QS signals to decrease their extracellular accumulation. Three phytochemicals, astragaloside IV, eugenol, and baicalin were selected, their effects on biofilm formation by Pseudomonas aeruginosa PA14 were studied, and the mechanisms determined. The inhibition efficiency of biofilm formation by 50 mg/L astragaloside IV, 1 mg/L eugenol, and 1 mg/L baicalin were 37%, 26%, and 26%, respectively. Confocal laser scanning microscopy and analysis of extracellular polymeric substances indicated that the three inhibitors affected the structure and composition of the biofilms. Furthermore, bacterial motility and a variety of QS-related virulence factors were suppressed by the inhibitor treatment due to changes in bacterial QS. Notably, the three inhibitors all decreased the extracellular concentration of the QS signaling molecule 3-oxo-C12-homoseine lactone by affecting the function of efflux pump MexAB-OprM. This indirectly interfered with the bacterial QS system and thus inhibited biofilm formation. In conclusion, this study revealed the inhibitory effects and inhibition mechanism of three phytochemicals on efflux pump and QS of P. aeruginosa and realized the inhibition on biofilm formation. We update the efflux pump inhibitor library and provide a new way for biofilm contamination control.


Asunto(s)
Percepción de Quorum , Saponinas , Eugenol/farmacología , Biopelículas , Saponinas/farmacología , Antibacterianos/farmacología , Proteínas Bacterianas
10.
BMC Psychiatry ; 23(1): 775, 2023 10 24.
Artículo en Inglés | MEDLINE | ID: mdl-37875902

RESUMEN

BACKGROUND: Alcohol dependence (AD) results in several medical problems including vitamin D deficiency and thyroid dysfunction. However, the relationship between these two complications remains unclear. The aim of the present study was to explore the relationship between serum vitamin D and thyroid hormone profiles in male patients with AD. METHODS: A total of 117 male patients with AD were enrolled. Vitamin D deficiency was defined as serum concentrations of the main circulating vitamin D, 25-hydroxy vitamin D [25(OH)D], below 50 nmol/L. The AD patients were divided into two groups accordingly: 46 patients with normal vitamin D levels (normal group) and 71 patients with vitamin D deficiency (deficiency group). The levels of thyroid hormone profiles including total triiodothyronine 3 (TT3), total thyroxine 4 (TT4), thyroid stimulating hormone (TSH), free triiodothyronine (fT3), and free thyroxine (fT4) between the two groups were compared. Correlation between the serum levels of 25(OH)D and thyroid hormone profiles was evaluated using simple correlation (Pearson's correlation) and multivariable analysis using linear regression models. RESULTS: The prevalence of vitamin D deficiency in male patients with AD is 60.7% (71/117; 95% confidence interval: 51.6-69.1%). Moreover, the serum levels of TT3 (t = -2.682, p = 0.009), TT4 (t = -2.033, p = 0.044), fT3 (t = -2.986, p = 0.003), and fT4 (t = -2.558, p = 0.012) in deficiency group were significantly higher than those in normal group. Post hoc power analyses showed that the power for fT3 was sufficient (power > 0.80). Furthermore, univariate analysis showed that the serum vitamin D levels were negatively correlated with the TT3 (r = -0.189, p = 0.044), fT3 (r = -0.350, p < 0.001), and fT4 (r = -0.198, p = 0.033) levels, while multivariate analysis indicated that only fT3 was independently related to the serum levels of vitamin D in male patients with AD. CONCLUSIONS: These results suggested that the serum vitamin D levels may be associated with fT3 in male patients with AD.


Asunto(s)
Alcoholismo , Deficiencia de Vitamina D , Humanos , Masculino , Triyodotironina , Tiroxina , Alcoholismo/complicaciones , Hormonas Tiroideas , Tirotropina , Vitamina D , Vitaminas , Deficiencia de Vitamina D/complicaciones
11.
J Cardiovasc Nurs ; 2023 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-37639559

RESUMEN

BACKGROUND: Return to work (RTW) is a critical component of rehabilitation for most young and middle-aged patients after an acute myocardial infarction (AMI). Its success is related to the quality of life and social psychological function of patients, and their social economic growth. However, healthcare professionals often do not deeply understand the patients' experience and their difficulties and coping methods during this process, which limits their ability to institute effective management and support. OBJECTIVE: In this study, we aimed to explore the lived experiences and change processes of young and middle-aged patients with AMI at the different stages of RTW. METHODS: A descriptive qualitative approach was used. Patients aged 20 to 59 years with AMI were recruited from the Department of Cardiology of 3 general hospitals. Data were collected via semistructured interviews. Data analysis was performed by conventional content analysis methods. RESULTS: In total, 18 participants were included. Five main themes emerged: (1) "chaos," (2) "rebuilding," (3) "conflict," (4) "coping," and (5) "benefits." Patients may be more concerned about physical recovery during the initial clinical event. They then begin to plan and adjust for an RTW. Patients in the maintenance phase need strategies to prevent, identify, and respond to conflicts and challenges to maintain long-term stable work. CONCLUSION: We identified several post-AMI stages spanning from the initial illness event to the maintenance of stable work. We described their perceived barriers, coping strategies, and support needs at these various stages. These data are crucial for healthcare professionals to develop improved vocational rehabilitation strategies for patients with AMI.

12.
Ultrason Imaging ; 45(1): 17-21, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36524737

RESUMEN

Twenty patients with pathologic nipple discharge underwent conventional galactography and contrast-enhanced ultrasound (CEUS) galactography. Images were reviewed for detection of suspicious lesions. Lesion localization information from CEUS galactography was recorded. We included 25 lesions from the 20 included patients. The pathological results revealed 13 intraductal papillomas. The detective rates of intraductal papilloma by conventional galactography and CEUS galactography were 92.31% and 100%, respectively. All the preoperative localizations of lesions from CEUS galactography were in accordance with the surgical detections. CEUS galactography is a highly effective tool for the detection of intraductal breast lesions, and it could provide accurate lesion localization information for an optimal surgical design.


Asunto(s)
Neoplasias de la Mama , Secreción del Pezón , Humanos , Femenino , Mamografía/métodos , Neoplasias de la Mama/diagnóstico por imagen , Mama , Secreción del Pezón/diagnóstico por imagen , Ultrasonografía
13.
Sensors (Basel) ; 23(20)2023 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-37896683

RESUMEN

Spectral calibration consists of the calibration of wavelengths and the measurement of the instrument's spectral response function (SRF). Unlike conventional slits, the absorbed aerosol sensors (AAS) are used as a slit homogenizer, in which the SRF is not a conventional Gaussian curve. To be more precise, the SRF is the convolution of the slit function of the spectrometer, the line spread function of the optical system, and the detector response function. The SRF of the slit homogenizer is a flat-topped multi-Gaussian function. Considering the convenience of fitting, a super-Gaussian function, which has a distribution similar to the flat-topped multi-Gaussian function, is employed to fit the measured data in a spectral calibration. According to the results, the SRF's shapes resembling a Gaussian curve with a flat top could be derived, which contains a full width at half maximum (FWHM) of 1.78-1.82 nm for the AAS. The results show that the correlation is about 0.99, which indicates the usefulness of the fitting function that could better characterize the SRF of the instrument.

14.
J Environ Manage ; 343: 118181, 2023 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-37229857

RESUMEN

With the recent increases in energy demands, the dust hazards of coal mining caused by transportation, loading and unloading and other processes are becoming increasingly serious. To control dust in open pit coal mines more environmentally friendly and efficiently, and to promote the use and development of non-in situ high-yield urease microorganisms for dust suppression in coal mines, Bacillus pasteurii was selected for dust suppression experiments in this article. Additionally, the growth of microorganisms in the coal dust microenvironment was simulated, and the effect of microbial mineralization products on the calorific value of upper coal dust was further studied. Our findings indicated that Bacillus pasteurii induced dust suppression by forming a calcite precipitate with non-uniform particle size to coal dust cementation. Moreover, after a single spray, the wind erosion resistance efficiency was 84% when the wind speed was set at 10 m/s. The growth of microorganisms and urease activity in the coal dust leachate were largely equal to those in the control group, reaching a peak at approximately 24 h, that the maximum growth quantity of OD600 was about 1.5, and the maximum urease activity was 11 mmol·L-1·min-1. The difference between the peak heat release rate of mixed coal dust and pure coal was only 4.82 kW/m2, which would not affect the value of coal products. Non in-situ Bacillus pasteurii can be growth metabolized normally in the microenvironment of coal dust. Finally, the mechanism of coal dust suppression by mineralization of microbial bacterial solution to form calcium carbonate was described by a reaction equation, which is important for further application and development of microbial dust suppressants.


Asunto(s)
Minas de Carbón , Sporosarcina , Polvo/análisis , Ureasa , Carbonato de Calcio , Minerales , Carbón Mineral/análisis
15.
Opt Express ; 30(24): 43172-43181, 2022 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-36523021

RESUMEN

Harvesting photoexcited hot electrons in metals promises a number of benefits in optical sensing. In practice, hot-electron optical sensors with tunable performance in electrical sensitivity are still absent. Herein, we propose a design to realize tunable hot-electron optical sensing. The proposed device consists of a one-dimensional grating deposited on a planar Au-MoS2-Au junction that is used for efficient hot-electron harvesting. Photoelectric simulations show that when grating-assisted plasmonic resonance is excited, bias voltage between two Au layers can be used to manipulate the magnitude and polarity of responsivity at the working wavelength. Therefore, the change in responsivity that originates from the change in refractive index of analyte in which the device is immersed can also be tuned by applied voltage. It is found that when bias voltage is 1 V, the electrical sensitivity doubled compared with that when applied voltage is absent. We believe the bias voltage-tuned strategy that is applied to planar hot-electron harvesting junctions facilitates the development of optical sensing.

16.
Opt Express ; 30(14): 25555-25566, 2022 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-36237083

RESUMEN

Cost-effective and high-responsivity photodetectors at a telecommunication wavelength of 1550 nm are highly desired in optical communication systems. Differing from conventional semiconductor-based photodetectors, several planar hot-electron photodetectors (HE PDs) that operate at 1550 nm have been reported. However, these devices were often comprised of many planar layers and exhibited relatively low responsivities. Herein, we propose a design of high-performance planar HE PDs consisting of five layers. Utilizing Fabry-Pérot (FP) resonance, the nearly perfect absorption of the proposed device can be achieved at the targeted wavelength of 1550 nm. Simulation results show that FP resonance orders are crucial for the optical absorption efficiencies, and then electrical responses. Analytical electrical calculations reveal that, benefiting from the strong absorption (>0.6) in the ultrathin Au layer with a thickness of 5 nm and the low Schottky barrier (0.5 eV) of Au-MoS2 contact, predicted responsivity of proposed HE PD at zero-order FP resonance is up to ∼10 mA/W. Our design provides a new approach to realize low-cost and efficient photodetection for optical communication technology.

17.
Environ Sci Technol ; 56(19): 14048-14058, 2022 10 04.
Artículo en Inglés | MEDLINE | ID: mdl-36074547

RESUMEN

Current research has widely applied heteroatom doping for the promotion of catalyst activity in peroxymonosulfate (PMS) systems; however, the relationship between heteroatom doping and stimulated activation mechanism transformation is not fully understood. Herein, we introduce nitrogen and sulfur doping into a Co@rGO material for PMS activation to degrade tetracycline (TC) and systematically investigate how heteroatom doping transformed the activation mechanism of the original Co@rGO/PMS system. N was homogeneously inserted into the reduced graphene oxide (rGO) matrix of Co@rGO, inducing a significant increase in the degradation efficiency without affecting the activation mechanism transformation. Additionally, S doping converted Co3O4 to Co4S3 in Co@rGO and transformed the cooperative oxidation pathway into a single non-radical pathway with stronger intensity, which led to a higher stability against environmental interferences. Notably, based on density functional theory (DFT) calculations, we demonstrated that Co4S3 had a higher energy barrier for PMS adsorption and cleavage than Co3O4, and therefore, the radical pathway was not easily stimulated by Co4S3. Overall, this study not only illustrated the improvement due to the heteroatom doping of Co@rGO for TC degradation in a PMS system but also bridged the knowledge gap between the catalyst structure and degradation performance through activation mechanism transformation drawn from theoretical and experimental analyses.


Asunto(s)
Nitrógeno , Peróxidos , Antibacterianos , Cobalto , Grafito , Nitrógeno/química , Óxidos , Peróxidos/química , Azufre , Tetraciclina
18.
Macromol Rapid Commun ; 43(22): e2200432, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35866519

RESUMEN

Ultrathin organic solar cells (OSCs) with both high power conversion efficiency (PCE) and operational stability are of great significance for the industrial applications but still challenging. Here, a polyimide (PI) substrate for high-performance and stable ultrathin OSCs, which is physically crosslinked via strong hydrogen bonds (denoted as HB-PI) to enhance the mechanical, thermal, solvent-resistant, and UV filtering properties (with a cut-off wavelength of 376 nm), is synthesized. An ultrathin flexible transparent composite electrode (FTCE, ≈7 µm) is fabricated via semi-embedding AgNWs in the HB-PI substrate. The FTCE possesses excellent optoelectronic property, smooth surface, and high mechanical stability simultaneously. Based on this FTCE, an ultrathin OSC is constructed with a PCE of 13.52% (average of 13.22%). Moreover, the ultrathin OSC shows outstanding mechanical stability (PCE decreased by less than 4% after 1000 bending cycles at a small bending radius of 0.5 mm) and superior UV light stability (no evident PCE degradation after irradiation under UV light for 10 h). This work will provide a new avenue for fabricating high-performance and stable ultrathin OSCs.

19.
J Nanobiotechnology ; 20(1): 96, 2022 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-35236356

RESUMEN

BACKGROUND: Despite extensive investigations on photothermal therapy, the clinical application is restricted due to poor stability, low therapeutic efficacy of photothermal therapy agents and its affinity loss in the multistep synthesis of delivery carriers. To address this, we designed an IR792-MCN@ZIF-8-PD-L1 siRNA (IM@ZP) nanoparticle drug delivery system. IM@ZP was prepared by in situ synthesis and physical adsorption, followed by characterization. Photothermal conversion ability of IM@ZP was assessed by irradiation of near-infrared (NIR) laser, followed by analysis of its effect on 4T1 cell viability, maturation of dendritic cells (DCs) and the secretion of related cytokines in vitro, and the changes of tumor infiltrating T cells and natural killer (NK) cells in vivo. Subcutaneous 4T1 tumor-bearing mouse and lung metastasis models were established to investigate the role of IM@ZP in killing tumor and inhibiting metastasis in vivo. RESULTS: IM@ZP was uniform nanoparticles of 81.67 nm with the characteristic UV absorption peak of IR792, and could effectively adsorb PD-L1 siRNA. Under the irradiation of 808 nm laser, IM@ZP exhibited excellent photothermal performance. IM@ZP could be efficiently uptaken by 4T1 cells, and had high transfection efficiency of PD-L1 siRNA. Upon NIR laser irradiation, IM@ZP effectively killed 4T1 cells, upregulated HSP70 expression, induced DC maturation and increased secretion of TNF-α and IL-6 in vitro. Moreover, in vivo experimental results revealed that IM@ZP enhanced photothermal immunotherapy as shown by promoted tumor infiltrating CD8 + and CD4 + T cells and NK cells, and inhibited tumor growth and lung metastasis. CONCLUSION: Together, biocompatible IM@ZP nanoparticles result in high photothermal immunotherapy efficiency and may have a great potential as a delivery system for sustained cancer therapy.


Asunto(s)
Nanopartículas , Neoplasias de la Mama Triple Negativas , Animales , Antígeno B7-H1 , Línea Celular Tumoral , Doxorrubicina/farmacología , Sistemas de Liberación de Medicamentos , Humanos , Inmunoterapia , Rayos Láser , Ratones , Fototerapia/métodos , ARN Interferente Pequeño/uso terapéutico , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico
20.
FASEB J ; 34(9): 11405-11420, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32729957

RESUMEN

Increasing evidence indicates that circular RNAs (circRNAs) play a crucial role in regulating microRNAs (miRs) and mRNAs during breast cancer (BC) progression. Based on the in silico analysis of circRNA/miR/mRNA in BC, we aim to define an important role of circRNA_000554 in BC in relation to miR-182 and zinc finger protein 36 (ZFP36). Low expression of circRNA_000554 and ZFP36, and high miR-182 expression were determined in the clinical BC tissues. CircRNA_000554 acted as a sponge of miR-182, and miR-182 directly targeted ZFP36. After that, in order to evaluate the effects of circRNA_000554, miR-182, and ZFP36 on cellular process, we evaluated in vitro epithelial-mesenchymal transition (EMT) and in vivo tumor growth after delivering a series of overexpression plasmids, mimic, inhibitor, or shRNAs into BC cells. Increasing circRNA_000554 suppressed EMT, cell invasion and migration during BC by depleting miR-182 and increasing ZFP36. The inhibitory effect of circRNA_000554 on tumor growth was validated in vivo. Taken together, the present study confirms that circRNA_000554 functioned as an inhibitor of EMT in BC and suggests a molecular mechanism that circRNA_000554 bound to miR-182 to upregulate ZFP36 in this process.


Asunto(s)
Neoplasias de la Mama/genética , Transición Epitelial-Mesenquimal/genética , Regulación Neoplásica de la Expresión Génica , MicroARNs/genética , ARN Circular/genética , Tristetraprolina/genética , Adulto , Anciano , Animales , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Línea Celular , Línea Celular Tumoral , Progresión de la Enfermedad , Femenino , Humanos , Células MCF-7 , Masculino , Ratones Endogámicos BALB C , Ratones Desnudos , Persona de Mediana Edad , Tristetraprolina/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto/métodos
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