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This paper presents the design and analysis of a metamaterial-based compact dual-band antenna for WBAN applications. The antenna is designed and fabricated on a 0.254 mm thick semi-flexible substrate, RT/Duroid® 5880, with a relative permittivity of 2.2 and a loss tangent of 0.0009. The total dimensions of the antenna are 0.26λo×0.19λo×0.002λo, where λo corresponds to the free space wavelength at 2.45 GHz. To enhance overall performance and isolate the antenna from adverse effects of the human body, it is backed by a 2×2 artificial magnetic conductor (AMC) plane. The total volume of the AMC integrated design is 0.55λo×0.55λo×0.002λo. The paper investigates the antenna's performance both with and without AMC integration, considering on- and off-body states, as well as various bending conditions in both E and H-planes. Results indicate that the AMC-integrated antenna gives improved measured gains of 6.61 dBi and 8.02 dBi, with bandwidths of 10.12% and 7.43% at 2.45 GHz and 5.80 GHz, respectively. Furthermore, the AMC integrated antenna reduces the specific absorption rate (SAR) to (>96%) and (>93%) at 2.45 GHz and 5.80 GHz, meeting FCC requirements for low SAR at both frequencies when placed in proximity to the human body. CST Microwave Studio (MWS) and Ansys High-Frequency Structure Simulation (HFSS), both full-wave simulation tools, are utilized to evaluate the antenna's performance and to characterize the AMC unit cell. The simulated and tested results are in mutual agreement. Due to its low profile, high gain, adequate bandwidth, low SAR values, and compact size, the AMC integrated antenna is considered suitable for WBAN applications.
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Desenho de Equipamento , Tecnologia sem Fio , Tecnologia sem Fio/instrumentação , HumanosRESUMO
With the increasing consumption of organic solvents in chemical and pharmaceutical industries, the environment pollution of volatile organic compounds (VOCs) has become an urgent problem. Therefore, the rapid-visual detection method is of great significance in the analysis of VOCs. Based on the fluorescence quenching/enhancement mechanism of carbon quantum dots (CQDs), with the help of carboxymethyl cellulose membrane with porous and large specific surface area structure, a series of green CQDs@carboxymethyl cellulose composite film (CQDs@CMC composite film) was prepared in this study. In the typical-targeted pollutants (toluene) detection application, a fluorescence spectroscopy method was established which could achieve the high sensitivity and strong specificity detection. The mainly conclusions were as follows: The fluorescence spectrometric detection method for toluene: A kind of hydrophobic Lmi/Bet CQDs@CMC composite film was prepared and characterized with imidazole/betaine CQDs and porous carboxymethyl cellulose composite film as raw materials. The toluene detection performance was studied, and the recognition mechanism was explored. The results showed that toluene enhanced the fluorescence of Lmi/Bet CQDs@CMC composite film. The fluorescence intensity of composite films was proportional to toluene concentration when the toluene concentration ranged from 200 to 2200 mg/L. The detection limit of toluene was 1.169 mg/L, which provides a theoretical basis for the detection of toluene by fluorescence spectrometry.
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Carbono , Carboximetilcelulose Sódica , Pontos Quânticos , Tolueno , Pontos Quânticos/química , Carboximetilcelulose Sódica/química , Tolueno/química , Tolueno/análise , Carbono/química , Espectrometria de Fluorescência/métodos , Gases/análise , Gases/química , Limite de Detecção , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/químicaRESUMO
BACKGROUND: Osteosarcoma is originated from skeletal system. Recombinant human proteoglycan 4 (rhPRG4) can inhibit cell proliferation and migration in multiple cancers. This research is designed to dig out the role and mechanism of PRG4 in osteosarcoma. METHODS: Human osteosarcoma cell lines, MG63 and 143B, were transfected with programmed death 1 (PD-L1) overexpression vectors and/or treated with 20, 50, and 100⯵g/mL rhPRG4, followed by the determination of cell viability, colony formation, sphere formation, invasion, migration, apoptosis, and the expressions of matrix metalloproteinases (MMPs), PD-L1 and apoptosis-related proteins. Tumor-bearing mouse models were constructed by injection of 143B cells and treatment of anti-PD-L1 antibody and/or adenovirus PRG4 (AdPRG4). Tumor volume was monitored, and immunohistochemical location of Ki67 was performed. Expressions of MMPs, transforming growth factor-ß (TGF-ß), PD-L1, and epithelial mesenchymal transition (EMT)-related proteins were measured in tumors. RESULTS: RhPRG4 (20, 50, and 100⯵g/mL) inhibited the viability, colony formation, sphere formation, invasion, migration, and the expressions of MMP2, MMP9 and Bcl2 in osteosarcoma cells, while promoting cell apoptosis as well as Bax and c-caspase3 expressions, at a dose-dependent manner; by contrast, PD-L1 overexpression reversed the above effects of 100⯵g/mL rhPRG4. AdPRG4 or anti-PD-L1 antibody decreased tumor volume, number of pulmonary metastasis nodule, Ki67 location, and expressions of TGF-ß, PD-L1, MMP2, MMP9, Vimentin, and Snail, but increased E-cadherin expression in tumor cells. Moreover, anti-PD-L1 antibody and AdPRG4 together functioned more effectively than them alone in reducing tumor burden. CONCLUSION: PRG4 represses the genesis and metastasis of osteosarcoma via inhibiting PD-L1 expression, and AdPRG4 enhances the effectiveness of anti-PD-L1 therapy.
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Antígeno B7-H1 , Osteossarcoma , Proteoglicanas , Animais , Humanos , Camundongos , Apoptose/efeitos dos fármacos , Antígeno B7-H1/metabolismo , Antígeno B7-H1/genética , Neoplasias Ósseas/patologia , Neoplasias Ósseas/metabolismo , Neoplasias Ósseas/genética , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Camundongos Nus , Metástase Neoplásica , Osteossarcoma/patologia , Osteossarcoma/metabolismo , Osteossarcoma/genética , Proteoglicanas/metabolismoRESUMO
Treatment of naphthenic acids (NAs) in wastewater is necessary due to its high toxicity and difficult degradation. In the heterogeneous Fenton-like advanced oxidation of organic pollutant system, the insufficient accessibility of oxidizing agent and NAs greatly hamper the reaction efficiency. CO2-responsive phase transfer materials derived from polyethylene glycol (PEG)-based deep eutectic solvents were specific targeted at the immiscible-binary phase system. The NAs oxidative degradation process was optimized including the kinds of catalyst (Molecular weight of PEG, constitute of DESs, and dosage.), temperature, flow rate of CO2, et al. With the help of fluorescence properties of catalyst, the hydrophilic-hydrophobic interaction was visual-monitored and further studied. The amphipathic property of PEG-200/Sodium persulfate/Polyether amine 230 (PEA230) greatly reduced the aqueous/organic phase transfer barrier between sodium persulfate and NAs (up to 84 %), thus accreting oxidation rate. The surface tension decreased from 35.364 mN/m to 28.595 mN/m. To control the reaction rate, the CO2 respond structure of amido played an important role. In addition, the interfacial transfer intermediates and oxidation pathways were also explored by nuclear magnetic resonance, flourier transform infrared spectroscopy, surface tension, and radical inhibition experiments. The mechanism of advanced oxidation of NAs catalyzed by CO2-responsive phase transfer catalyst was proposed, which would made up for the deficiency of the system theory of heterogeneous chemical oxidation of organic pollutants.
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In this paper, we investigated leader-following consensus control for nonlinear multi-agent systems (MASs) experiencing denial-of-service (DoS) attacks. We proposed a distributed control strategy incorporating an adaptive scheme and a state feedback control gain to eliminate the effects of system nonlinear dynamics and uncertainties. In addition, we introduced a dynamic event-triggered control (DETC) to minimize the utilization of communication resources. Finally, we provided simulation results to show the validity of the proposed approach.
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Vaccinia virus (VACV) is a large DNA virus that encodes scores of proteins that modulate the host immune response. VACV protein C4 is one such immunomodulator known to inhibit the activation of both the NF-κB signaling cascade and the DNA-PK-mediated DNA sensing pathway. Here, we show that the N-terminal region of C4, which neither inhibits NF-κB nor mediates interaction with DNA-PK, still contributes to virus virulence. Furthermore, this domain interacts directly and with high affinity to the C-terminal domain of filamin B (FLNB). FLNB is a large actin-binding protein that stabilizes the F-actin network and is implicated in other cellular processes. Deletion of FLNB from cells results in larger VACV plaques and increased infectious viral yield, indicating that FLNB restricts VACV spread. These data demonstrate that C4 has a new function that contributes to virulence and engages the cytoskeleton. Furthermore, we show that the cytoskeleton performs further previously uncharacterized functions during VACV infection. IMPORTANCE: Vaccinia virus (VACV), the vaccine against smallpox and monkeypox, encodes many proteins to counteract the host immune response. Investigating these proteins provides insights into viral immune evasion mechanisms and thereby indicates how to engineer safer and more immunogenic VACV-based vaccines. Here, we report that the N-terminal domain of VACV protein C4 interacts directly with the cytoskeletal protein filamin B (FLNB), and this domain of C4 contributes to virus virulence. Furthermore, VACV replicates and spreads better in cells lacking FLNB, thus demonstrating that FLNB has antiviral activity. VACV utilizes the cytoskeleton for movement within and between cells; however, previous studies show no involvement of C4 in VACV replication or spread. Thus, C4 associates with FLNB for a different reason, suggesting that the cytoskeleton has further uncharacterized roles during virus infection.
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Filaminas , Vaccinia virus , Proteínas Virais , Humanos , Linhagem Celular , DNA/metabolismo , Filaminas/genética , Filaminas/metabolismo , NF-kappa B/metabolismo , Vacínia/virologia , Vaccinia virus/patogenicidade , Vaccinia virus/fisiologia , Proteínas Virais/genética , Proteínas Virais/metabolismo , AnimaisRESUMO
This paper investigates achieving leader-following consensus in a class of multi-agent systems with nonlinear dynamics. Initially, it introduces a dynamic event-triggered strategy designed to effectively alleviate the strain on the system's communication resources. Subsequently, a distributed control strategy is proposed and implemented in the nonlinear leader-follower system using the dynamic event-triggered mechanism, aiming to ensure synchronization across all nodes at an exponential convergence speed. Thirdly, the research shows that under the dynamic event-triggered strategy the minimum event interval of any two consecutive triggers guarantees the elimination of Zeno behavior. Lastly, the validity of the calculation results is verified by a simulation example.
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BACKGROUND: We conducted a meta-analysis to provide evidence-based results for the predictive values of sarcopenia, skeletal muscle index, psoas muscle index and the myosteatosis regarding the impact of survival outcomes and tumor response in patients treated by trans-arterial (chemo)-embolization (TAE/TACE), thereby optimizing therapeutic strategies and maximizing clinical benefits for hepatocellular carcinoma patients. METHODS: Qualified studies were retrieved from PubMed, the Cochrane Library, EMBASE, and Google Scholar before June 19, 2023. We investigated the relationships between sarcopenia, SMI, PMI, myosteatosis, and the overall survival of TAE/TACE-treated hepatocellular carcinoma patients with pooling data. RESULTS: A total of 167 studies were collected and 12 studies were finally included for analysis. The meta-analysis assisted that the sarcopenia (HR: 1.46, 95% CI: 1.30-1.64, p < 0.001), skeletal muscle index (HR: 1.48, 95% CI: 1.29-1.69, p < 0.001), and psoas muscle index (HR: 1.45, 95% CI: 1.19-1.77, p < 0.001) were significantly related to a shorter OS of hepatocellular carcinoma patients who treated by TAE/TACE. Sarcopenia significantly contributed to a lower objective response rate of TAE/TACE treated hepatocellular carcinoma patients (OR: 0.80, 95% CI: 0.65-0.98, p = 0.032). But there was no significant association between the myosteatosis and the overall survival (HR: 1.29, 95% CI: 0.74-2.25, p = 0.366). Sensitivity analysis supported the stability and dependability of above analyses conclusions. CONCLUSION: Sarcopenia, skeletal muscle index and psoas muscle index, are significant prognostic predictors for TAE/TACE treated hepatocellular carcinoma patients. While myosteasis does not demonstrate a prognostic impact on the overall survival of TAE/TACE treated hepatocellular carcinoma patients.