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BACKGROUND: CD83 are closely related to the pathogenesis of immune thrombocytopenia (ITP), but the exact mechanism remains unclear. AIM: To explore the relationship between CD83 and CD4+ T cell subsets and clarify the role of CD83 in the pathogenesis of ITP. METHODS: RT-qPCR and Flow cytometry were used to illustrate CD83 expression. The downregulation and overexpression of DC-CD83 were co-cultured with CD4+ T cells to detect cell proliferation, co-cultured supernatant cytokines and Tregs expression. RESULTS: The results indicate that the ITP patients showed higher expression of CD83 than the healthy controls. The proliferation of CD4+ T cells was inhibited by downregulation of DCs-CD83 but promoted by overexpression of DCs-CD83. siRNA-CD83 inhibited proinflammatory IFN-γ and IL-17 secretion while raising TGF-ß, IL-10 concentrations. Overexpression of DCs-CD83 promoted Tregs expression. CONCLUSION: The Th1/Th2 and Th17/Tregs polarization were reversed via interfering DCs with siRNA-CD83. CD83 plays an important role in ITP pathogenesis, suggesting novel treatment for ITP patients.
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Antígenos CD , Antígeno CD83 , Imunoglobulinas , Glicoproteínas de Membrana , Púrpura Trombocitopênica Idiopática , Humanos , Púrpura Trombocitopênica Idiopática/imunologia , Púrpura Trombocitopênica Idiopática/patologia , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Antígenos CD/metabolismo , Imunoglobulinas/genética , Imunoglobulinas/metabolismo , Feminino , Masculino , Adulto , Pessoa de Meia-Idade , Citocinas/metabolismo , Linfócitos T Reguladores/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Células Dendríticas/imunologia , Células Dendríticas/metabolismoRESUMO
BACKGROUND: Cardiotoxicity has been corroborated to be the toxic influence of cisplatin (CDDP). Oxidative stress and cardiomyocyte apoptosis play a vital part in cardiotoxicity induced by CDDP. Salvianolic acid Salvianolic acid B (SalB) is a monomeric component of Salvia miltiorrhiza, which has antioxidant and anti-inflammatory influences. In this research, we explored the mechanism of SalB in cardiotoxicity induced by CDDP. METHOD: 36 Wistar rats were separated into sham subgroup, CDDP (10 mg/kg) subgroup, CDDP (10 mg/kg) + SalB (1 µM) subgroup at random, CDDP (10 mg/kg) + SalB (5 µM) subgroup and CDDP (10 mg/kg) + SalB (10 µM) subgroup, Nicotinic Acid Riboside (NAR, 5 µM), with 6 rats in each subgroup. The cardiac function of rats in each subgroup was estimated by echocardiography, and hematoxylin-eosin (HE) staining and Masson staining corroborated the pathological changes of cardiac tissue. Biochemical kits were utilized for detecting the lactate dehydrogenase (LDH), creatine kinase (CK), interleukin-1ß (IL-1ß), IL-18, and caspase-1 concentrations in serum, superoxide dismutase (SOD), and malondialdehyde (MDA) in myocardial tissue, TdT-mediated dUTP Nick-End Labeling (TUNEL) staining, and flow cytometry were utilized for estimating the apoptosis level in myocardial tissue, western blot was used for estimating caspase-3, Bcl2-Associated X (Bax) levels in myocardial tissue and proteins levels related to Nuclear factor E2 related factor 2 (Nrf2) signal pathway. RESULTS: CDDP-induced cardiac dysfunction, myocardial injury, boosted LDH and CK levels in serum (p < 0.05), memorably increased oxidative stress level in myocardial tissue (p < 0.05), boosted inflammatory response (p < 0.05), boosted apoptosis rate of cardiomyocytes (p < 0.05), and declined the Nrf2, NAD(P)H quinone oxidoreductase 1 (NQO1), heme oxygenase 1 (HO-1) protein levels (p < 0.05). Interestingly, SalB remedy could alleviate the changes caused by CDDP in the above parameters, significantly decrease the level of myocardial oxidative stress and apoptosis (p < 0.05). CONCLUSIONS: SalB ameliorates the injury of cardiomyocytes induced by chemotherapy through oxidative stress mediated by the Nrf2/antioxidant response element (ARE) signal pathway.
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Elementos de Resposta Antioxidante , Benzofuranos , Depsídeos , Miócitos Cardíacos , Ratos , Animais , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Ratos Sprague-Dawley , Cardiotoxicidade/metabolismo , Ratos Wistar , Transdução de Sinais , Estresse Oxidativo , ApoptoseRESUMO
This work presents highly responsive gate-controlled p-GaN/AlGaN/GaN ultraviolet photodetectors (UVPDs) on Si substrates with a high-transmittance ITO gate. The two-dimensional electron gas (2DEG) in the quantum well of the polarized AlGaN/GaN heterojunction was efficiently depleted by the p-GaN gate, leading to a high photo-to-dark current ratio (PDCR) of 3.2 × 105. The quantum wells of the p-GaN/AlGaN and AlGaN/GaN heterojunctions can trap the holes and electrons excited by the UV illumination, thus efficiently triggering a photovoltaic effect and photoconductive effect, separately. Furthermore, the prepared photodetectors allow flexible adjustment of the static bias point, making it adaptable to different environments. Compared to traditional thin-film semi-transparent Ni/Au gates, indium tin oxide (ITO) exhibits higher transmittance. Under 355 nm illumination, the photodetector exhibited a super-high responsivity exceeding 3.5 × 104 A/W, and it could even exceed 106 A/W under 300 nm illumination. The well-designed UVPD combines both the advantages of the high-transmittance ITO gate and the structure of the commercialized p-GaN/AlGaN/GaN high-electron-mobility transistors (HEMTs), which opens a new possibility of fabricating large-scale, low-cost, and high-performance UVPDs in the future.
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GaAs-based oxide-confined vertical-cavity surface-emitting lasers (VCSELs) exhibit relatively low resistance against reliability-related damage. In order to gain a deeper understanding of the degradation and failure mechanism in oxide-confined VCSELs caused by electrostatic discharge (ESD)-induced defect proliferation, we investigated the effects of ESD stress on the degradation of optical-electrical characteristics and the evolution of defects in VCSELs under human body model test condition. The degradation threshold values for forward and reverse ESD pulse amplitudes were estimated to be 200â V and -50â V, respectively. Notably, VCSELs demonstrated greater sensitivity to reverse bias ESD compared to forward bias ESD. Analysis of optical emission and microstructure provided evidence that the device failure is attributed to an increase in ESD current density, leading to the multiplication of dark line defects (DLDs) originating from the edge of the device's oxide aperture. The formation of defects occurred suddenly in discrete events within small regions, rather than progressing gradually and uniformly. These defects propagated and led to damage across the entire active region. We believe that our results would be meaningful for improving the reliability of VCSEL in the future.
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The conventional dose of recombinant human thrombopoietin (rhTPO) in the treatment of immune thrombocytopenia (ITP) is 300 U/kg per day, but the clinical reaction rate is not satisfactory. Accordingly, we explored the efficacy and safety of increasing rhTPO dose in the treatment of ITP. A retrospective study was conducted to collect the clinical data of 105 ITP patients who were divided into two groups, a low-dose group (15 000 U/day) and a high-dose group (30 000 U/day) according to the dose of rhTPO. The total effective rate of the low-dose group and the high-dose group was 31/44 (70.45%) vs. 56/61 (91.80%) (P = .049), and the average time of using rhTPO in the high-dose group was shorter than that in the low-dose group (7 days vs. 10 days, P = .001). On the 7th and 14th day of treatment, the efficacy of the high-dose group was better than that of the low-dose group [45/61 (73.77%) vs. 17/44 (38.64%), P < .001; 55/60 (91.67%) vs. 30/44 (68.18%), P < .05)]. The incidence of treatment related adverse events in the low-dose group and the high-dose group was 6/44 (13.64%) vs. 6/61 (9.84%) (P > .05), which were mild and transient in nature. In our study, high-dose rhTPO had good efficacy and high safety in the treatment of ITP with the efficacy better than low-dose rhTPO especially at day 7.
What is the context? Immune thrombocytopenia (ITP) is an acquired autoimmune disease characterized by low platelet counts due to increased platelet destruction and impaired platelet production.The therapy direction of ITP involves promoting platelet generation, reducing excessive platelet destruction, immune regulation and so on.Recombinant human thrombopoietin (rhTPO), a promote platelet production drug, has pharmacological action similar to that of endogenous TPO. It can increase platelet count rapidly and effectively and has immunological regulation effect as well.It is found that rhTPO can rapidly and effectively increase platelet count, which has potential clinical application value in emergency situations.What is new? Traditionally, rhTPO has been recommended at 300 U/kg per day. Although it can greatly improve the treatment effect of ITP, the effect is not very satisfactory. In clinical practice, it has been observed that rhTPO dosage is often relatively insufficient and the therapeutic effect is poor. Therefore, we explored the efficacy and safety of increasing rhTPO dose in the treatment of ITP.Within the efficacy and safety of rhTPO 15 000 U/day and 30 000 U/day in the treatment of ITP, our analyses suggest that:The early response rate of the high-dose group was better than that of the low-dose group.In the high-dose group, the effective rate of rhTPO alone or combined with glucocorticoids was more than 90%.Treatment related adverse events occurred at a low rate and remained mild and transient.What is the impact? Comparing with conventional dose rhTPO, high-dose rhTPO may have better efficacy and safety in the treatment of immune thrombocytopenia and shorter administration time.
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Púrpura Trombocitopênica Idiopática , Trombocitopenia , Humanos , Púrpura Trombocitopênica Idiopática/tratamento farmacológico , Trombopoetina/efeitos adversos , Contagem de Plaquetas , Estudos Retrospectivos , Trombocitopenia/tratamento farmacológico , Proteínas Recombinantes/uso terapêuticoRESUMO
In the field of diamond MESFETs, this work is what we believe to be the first to investigate the optoelectronic properties of hydrogen-terminated polycrystalline diamond MESFETs under visible and near-UV light irradiation. It is shown that the diamond MESFETs are well suited for weak light detection in the near-ultraviolet region around the wavelength of 368â nm, with a responsivity of 6.14 × 106 A/W and an external quantum efficiency of 2.1 × 107 when the incident light power at 368.7â nm is only 0.75 µW/cm2. For incident light at 275.1â nm, the device's sensitivity and EQE increase as the incident light power increases; at an incident light power of 175.32 µW/cm2 and a VGS of -1â V, the device's sensitivity is 2.9 × 105 A/W and the EQE is 1.3 × 106. For incident light in the wavelength range of 660â nm to 404â nm with an optical power of 70 µW/cm2, the device achieves an average responsivity of 1.21 × 105 A/W. This indicates that hydrogen-terminated polycrystalline diamond MESFETs are suitable for visible and near-UV light detection, especially for weak near-UV light detection. However, the transient response test of the device shows a long relaxation time of about 0.2 s, so it is not yet suitable for high-speed UV communication or detection.
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Optrodes, which are single shaft neural probes integrated with microelectrodes and optical light sources, offer a remarkable opportunity to simultaneously record and modulate neural activities using light within an animal's brain; however, a common problem with optrodes is that stimulation artifacts can be observed in the neural recordings of microelectrodes when the light source on the optrode is activated. These stimulation artifacts are undesirable contaminants, and they cause interpretation complexity when analyzing the recorded neural activities. In this paper, we tried to mitigate the effects of the stimulation artifacts by developing a low-noise, double-sided optrode integrated with multiple Electromagnetic Shielding (EMS) layers. The LED and microelectrodes were constructed separately on the top epitaxial and bottom substrate layers, and EMS layers were used to separate the microelectrodes and LED to reduce signal cross-talks. Compared with conventional single-sided designs, in which the LED and microelectrodes are constructed on the same side, our results indicate that double-sided optrodes can significantly reduce the presence of stimulation artifacts. In addition, the presence of stimulation artifacts can further be reduced by decreasing the voltage difference and increasing the rise/fall time of the driving LED pulsed voltage. With all these strategies, the presence of stimulation artifacts was significantly reduced by ~76%. As well as stimulation suppression, the sapphire substrate also provided strong mechanical stiffness and support to the optrodes, as well as improved electronic stability, thus making the double-sided sapphire optrodes highly suitable for optogenetic neuroscience research on animal models.
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Complicações Hematológicas na Gravidez , Púrpura Trombocitopênica Trombótica , Humanos , Feminino , Gravidez , Púrpura Trombocitopênica Trombótica/tratamento farmacológico , Rituximab/uso terapêutico , Países em Desenvolvimento , Proteína ADAMTS13 , Complicações Hematológicas na Gravidez/tratamento farmacológico , Troca PlasmáticaRESUMO
Water splitting for yielding high-purity hydrogen represents the ultimate choice to reduce carbon dioxide emission owing to the superior energy density and zero-pollution emission after combustion. However, the high electricity consumption and requirement of large quantities of pure water impede its large-scale application. Here, a triboelectric nanogenerator (W-TENG) converting offshore wind energy into electricity is proposed for commercial electric energy saving and cost reduction. By introducing PTFE/POM dielectric pairs with matched HOMO/LUMO band gap energy, a high charge density is achieved to promote the output of W-TENG. With the impedance matching design of transformers with the internal resistance of W-TENG, the output current is further enhanced from 1.42 mA to 54.5 mA with a conversion efficiency of more than 92.0%. Furthermore, benefiting from the high electrocatalytic activity (overpotential = 166 mV and Tafel slope = 181.2 mV dec-1) of a carbon paper supported NiCoP-MOF catalyst, natural seawater can be adopted as a resource for in situ hydrogen production without acid or alkaline additives. Therefore, the self-powered seawater electrolysis system achieves a H2 production rate as high as 1273.9 µL min-1 m-2 with a conversion efficiency of 78.9%, demonstrating a more practical strategy for conversion of wind energy into renewable hydrogen energy.
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Traditional GaAs-based frequency multipliers still exhibit great challenges to meet the demand for solid-state high-power THz sources due to low breakdown voltage and heat dissipation of the Schottky barrier diode (SBD). In this study, a GaN SBD chain was fabricated with n-/n+-GaN structure. As a consequence, the breakdown voltage of 54.9 V at 1 µA and cut-off frequency of 587.5 GHz at zero bias were obtained. A 120 GHz frequency-doubler module based on the GaN SBD chain was designed and fabricated. When driven with 500 mW input power in a continuous wave, the output power of the frequency-doubler module was 15.1 mW at 120 GHz. Moreover, the experiments show that the frequency-doubler module can endure an input power of 2 W. In addition, it is worth noting that the SBD chain works well at an anode temperature of 337.2 °C.
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OBJECTIVE: To assess the association between three-dimensional inclination of the osseous structures of temporomandibular joints (TMJ) and the risk of disc displacement (DD). METHODS: The 120 TMJs of 60 patients were evaluated. According to magnetic resonance images, disc position was classified as normal, anterior DD with reduction (ADDWR) and without reduction (ADDWoR) and as normal, medial DD (MDD), and lateral DD (LDD) on the sagittal and coronal views, respectively. Condyle and eminence inclinations were measured using cone beam computed tomography. RESULTS: Smaller horizontal condylar inclination was associated with ADDWoR (p < 0.05). Larger coronal condylar inclination was associated with ADDWR (p < 0.05) and LDD (p < 0.05). There was no association between sagittal eminence inclination and DD (p < 0.05). CONCLUSION: Medial condylar rotation in the axial view may be associated with ADDWoR. The condyle head horizontally inclined in the coronal view may be associated with ADDWR and LDD.
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A self-charging power system harvesting random and low-frequency wave energy into electricity provides a promising strategy for the construction of smart oceans. However, the system faces huge challenges of easy corrosion in the marine environment and the utilization of toxic organic electrolytes in energy storage devices. To address the issues above, a seawater supercapacitor (SWSC) for the marine self-charging power system is rationally proposed by using a conductive polymer, polypyrrole with hollow morphology (h-PPy), to enhance the stability and capacitance while using seawater as an eco-friendly electrolyte to reduce the cost and achieve sustainability. The hollow design provides a shortcut for the ion transportation of seawater into the h-PPy electrode, and the SWSC achieves a high power density of 4.32 kW kg-1 under an energy density of 5.12 W h kg-1. Even after 180 days in seawater, h-PPy still endows a mass retention of 99.9%, enabling the SWSC to maintain a stability of 99.3% after 6000 cycles. More importantly, when combined with a TENG module as the marine self-charging power system to harvest wave energy, the system provides a stable output in water wave to drive electronics and sensors, which shows a competitive potential in the smart ocean and marine internet of things.
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The liquid-solid triboelectric nanogenerator is broadly studied for its self-powered sensing and blue energy harvesting, thanks to its low wear and highly efficient contact. However, the corresponding research studies focusing on deionized-water liquid-solid triboelectric nanogenerators (DL-TENGs) and seawater-type liquid-solid TENGs (SL-TENGs) are rarely being carried out at present. Here, a SL-TENG is fabricated by applying a dielectric film as the organic coating and coated and uncoated steel hull as the two electrodes. Based on the reasonable material selection of the dielectric film, the SL-TENG showed excellent performance, which benefits from the good triboelectrification performance and weak ion adsorption effect. In addition, compared with commercial marine anticorrosive coatings, the friction coefficient of the SL-TENG with the seawater can be reduced 43.8%, which is significantly beneficial to reduce the sailing resistance of ships. More importantly, the uncoated steel electrode can obtain a high potential in highly corrosive seawater, which can enable it to perform the function of marine anticorrosive agents. Our finding provides a potential strategy to evade the marine anticorrosion of ships.
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Triboelectric nanogenerator (TENG) has presented the huge potential application in distributed energy field which can realize the conversion from dispersed mechanical energy to electric energy. However, the natural characteristic of pulse output for conventional TENG, which means high crest factor, is defective for directly driving electronics. Here, a strategy to convert the pulse alternate current of TENG into a direct current with low crest factor is achieved through introducing a phase difference design into the structure of TENG. As a result, a direct current with a crest factor of 1.07 is obtained in a rotational free-standing TENG (RF-TENG) array at optimum phase difference, where 3D digital printing technology is used to accurately control the parameter of phase difference. Moreover, an adaptable contact mode structure between tribolayer and electrode improves the durability of the RF-TENG array, which can present a stable performance after working 1.2 million cycles. This work provides a combined strategy to obtain a long-lifetime and low crest-factor TENG for its large-scale application in energy harvesting.
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Integrated optrodes for optogenetics have been becoming a significant tool in neuroscience through the combination of offering accurate stimulation to target cells and recording biological signals simultaneously. This makes it not just be widely used in neuroscience researches, but also have a great potential to be employed in future treatments in clinical neurological diseases. To optimize the integrated optrodes, this paper aimed to investigate the influence of surface material and illumination upon the performance of the microelectrode/electrolyte interface and build a corresponding evaluation system. In this work, an integrated planar optrode with a blue LED and microelectrodes was designed and fabricated. The charge transfer mechanism on the interface was theoretically modeled and experimentally verified. An evaluation system for assessing microelectrodes was also built up. Using this system, the proposed model of various biocompatible surface materials on microelectrodes was further investigated under different illumination conditions. The influence of illumination on the microelectrode/electrolyte interface was the cause of optical artifacts, which interfere the biological signal recording. It was found that surface materials had a great effect on the charge transfer capacity, electrical stability and recoverability, photostability, and especially optical artifacts. The metal with better charge transfer capacity and electrical stability is highly possible to have a better performance on the optical artifacts, regardless of its electrical recoverability and photostability under the illumination conditions of optogenetics. Among the five metals used in our investigation, iridium served as the best surface material for the proposed integrated optrodes. Thus, optimizing the surface material for optrodes could reduce optical interference, enhance the quality of the neural signal recording for optogenetics, and thus help to advance the research in neuroscience.
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The rapid development of Internet of Things and artificial intelligence brings increasing attention on the harvesting of distributed energy by using triboelectric nanogenerator (TENG), especially the direct current TENG (DC-TENG). It is essential to select appropriate triboelectric materials for obtaining a high performance TENG. In this work, we provide a set of rules for selecting the triboelectric materials for DC-TENG based on several basic parameters, including surface charge density, friction coefficient, polarization, utilization rate of charges, and stability. On the basis of the selection rules, polyvinyl chloride, used widely in industry rather than in TENG, is selected as the triboelectric layer. Its effective charge density can reach up to ~8.80 mC m-2 in a microstructure-designed DC-TENG, which is a new record for all kinds of TENGs. This work can offer a basic guideline for the triboelectric materials selection and promote the practical applications of DC-TENG.
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OBJECTIVE: The objective of this study was to compare the diagnostic performance of magnetic resonance imaging (MRI) and computed tomography (CT) in differentiating pleomorphic adenomas from Warthin tumors using radiomics. STUDY DESIGN: We retrospectively reviewed 626 patients who underwent preoperative MRI or CT for parotid tumor diagnosis. Patient groups were balanced by propensity score matching (PSM) and 123 radiomic features were extracted from tumor images. Radiomic signatures (rad-scores) were generated using a least absolute shrinkage and selection operator logistic regression model. The Canny edge detector was used to define tumor borders (border index). The diagnostic performance of rad-score and border index before and after PSM was evaluated with area under the receiver operating characteristic curve analysis. RESULTS: For differentiation of pleomorphic adenomas and Warthin tumors, rad-score and border index areas under the curve for MRI after PSM were 0.911 (95% confidence interval [CI], 0.871-0.951) and 0.716 (95% CI, 0.646-0.787), respectively; those for CT were 0.876 (95% CI, 0.829-0.923) and 0.608 (95% CI, 0.527-0.690), respectively. Tumor border index on MRI, but not CT, had superior diagnostic performance (P < .05); MRI- and CT-based rad-scores showed similar performance (P >.05). CONCLUSIONS: MRI is superior to CT for tumor margin examination; however, the radiomics features of both modalities showed no difference.
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Adenoma Pleomorfo , Neoplasias Parotídeas , Adenoma Pleomorfo/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Neoplasias Parotídeas/diagnóstico por imagem , Estudos Retrospectivos , Tomografia Computadorizada por Raios XRESUMO
OBJECTIVES: To explore the effectiveness of magnetic resonance image (MRI)-based biomarkers for identifying benign and malignant parotid tumors via diagnostic model analysis. METHODS: This retrospective study included 109 patients (development cohort and validation cohort) who underwent MRI preoperatively, including T1- and T2-weighted images. Parameters based on 2D or 3D texture analysis were extracted from tumor lesions by MaZda software, fisher discriminant and bootstrap method were used to perform parameter reduction, diagnostic models with the selected biomarkers were established along with clinical data, model performance (discrimination and calibration) was furtherly evaluated by internal and external validation, decision curve analysis was applied to measure the improvement of clinical benefits. RESULTS: S(5,5) Entrop, S(0,1) ASM, WavEnHH (s-4), S(1,1,0) Entropy and Perc.10% were significantly associated with the pathological diagnosis of parotid tumor (benign versus malignancy), when adding these biomarkers to the regression analysis, model performance significantly improved in the development cohort (likelihood-ratio-test; p < 0.05, with an increase of AUC from 0.72 (reference model) to 0.85), and these results were maintained in a small external validation cohort. Decision curve analysis indicated that clinical benefit was greater with the application of MRI-based biomarkers. CONCLUSIONS: MRI-based texture analysis is proven to be an effective tool in differentiating benign and malignant parotid tumors, preoperative diagnosis was improved with the selected biomarkers compared to the reference model.
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Neoplasias Parotídeas , Biomarcadores , Diagnóstico Diferencial , Humanos , Imageamento por Ressonância Magnética , Neoplasias Parotídeas/diagnóstico por imagem , Estudos RetrospectivosRESUMO
An ocean wave contains various marine information, but it is generally difficult to obtain the high-precision quantification to meet the needs of ocean development and utilization. Here, we report a self-powered and high-performance triboelectric ocean-wave spectrum sensor (TOSS) fabricated using a tubular triboelectric nanogenerator (TENG) and hollow ball buoy, which not only can adapt to the measurement of ocean surface water waves in any direction but also can eliminate the influence of seawater on the performance of the sensor. Based on the high-sensitivity advantage of TENG, an ultrahigh sensitivity of 2530 mV mm-1 (which is 100 times higher than that of previous work) and a minimal monitoring error of 0.1% are achieved in monitoring wave height and wave period, respectively. Importantly, six basic ocean-wave parameters (wave height, wave period, wave frequency, wave velocity, wavelength, and wave steepness), wave velocity spectrum, and mechanical energy spectrum have been derived by the electrical signals of TOSS. Our finding not only can provide ocean-wave parameters but also can offer significant and accurate data support for cloud computing of ocean big data.
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Core-shell-structured BaTiO3-poly( tert-butyl acrylate) (P tBA) nanoparticles are successfully prepared by in situ atom transfer radical polymerization of tert-butyl acrylate ( tBA) on BaTiO3 nanoparticle surface. The thickness of the P tBA shell layer could be controlled by adjusting the feed ratio of tBA to BaTiO3. The BaTiO3-P tBA nanoparticles are introduced into poly(vinylidene fluoride) (PVDF) matrix to form a BaTiO3-P tBA/PVDF nanocomposite. The nanocomposites keep the flexibility of the PVDF matrix with enhanced dielectric constant (â¼15@100 Hz) because of the high permittivity of inorganic particles and the ester functional groups in the P tBA. Furthermore, the BaTiO3-P tBA/PVDF nanocomposites demonstrate the inherent small dielectric loss of the PVDF matrix in the tested frequency range. The high electric field dielectric constant of the nanocomposite film was investigated by polarization hysteresis loops. The high electric field effective dielectric constant of the nanocomposite is 26.5 at 150 MV/m. The output current density of the nanocomposite-based triboelectric nanogenerator (TENG) is 2.1 µA/cm2, which is above 2.5 times higher than the corresponding pure PVDF-based TENG.