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1.
Sensors (Basel) ; 23(17)2023 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-37688074

RESUMO

This paper investigates the power control and resource allocation problem in a simultaneously wireless information and power transfer (SWIPT)-based cognitive two-way relay network, in which two secondary users exchange information through a power splitting (PS) energy harvesting (EH) cognitive relay node underlay in a primary network. To enhance the secondary networks's transmission ability without detriment to the primary network, we formulate an optimization to maximize the minimum transmission rates of the cognitive users by jointly optimizing power allocation at the sources, the time allocation of transmission frames and power splitting at the relay, under the constraint that the transmission power of the cognitive network is set not to exceed the primary user interference threshold to ensure primary work performance. To efficiently solve this problem, a sub-optimal algorithm named the joint power control and resource allocation (JPCRA) scheme is proposed, in which we decouple the non-convex problem into convex problems and use alternative steps in the optimization algorithm to get final solutions. Numerical results reveal that the proposed scheme enhances transmission fairness and outperforms three traditional schemes.

2.
IET Nanobiotechnol ; 17(4): 360-367, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37095723

RESUMO

To assess and evaluate Chitosan-Metamizole nanoparticles for fracture healing and analgesic potential, nanoparticles were formulated using the ionotropic gelation method. The nanoparticles were evaluated for particle size, zeta potential, polydispersity index, loading efficiency, surface characteristics and drug release properties. The analgesic activity was determined in carrageenan-induced arthritic male Wister rats. Further fracture healing potency, mechanical testing, radiographic examination and bone histology of the femur were studied. The drug loading efficiency of 11.38%-17.45%, particle size of 140-220 nm, and zeta potential of 19.12-23.14 mV were observed with a spherical, smooth appearance. Nanoparticles showed sustained release behaviour over a longer period. Nearly 4-fold inhibition of oedema was observed in animals treated with nanoparticles with excellent fracture healing potential. The femurs treated with nanoparticles required greater force to fracture. Nanoparticles significantly improved the strength and healing process. Histopathological studies showed the potential of nanoparticles in the healing process. The study confirmed the potential of nanoparticles in fracture healing and enhancement of analgesic activity.


Assuntos
Quitosana , Nanopartículas , Ratos , Masculino , Animais , Quitosana/farmacologia , Consolidação da Fratura , Dipirona , Ratos Wistar , Tamanho da Partícula , Portadores de Fármacos
3.
Sensors (Basel) ; 22(13)2022 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-35808530

RESUMO

As an advanced technology, simultaneous wireless information and power transfer (SWIPT), combined with the internet of things (IoT) devices, can effectively extend the online cycle of the terminal. To cope with the fluctuation of energy harvesting by the hybrid access points (H-AP), the energy cooperation base station is introduced to realize the sharing of renewable energy. In this paper, we study the SWIPT-enabled IoT networks with cooperation. Our goal is to maximize the energy efficiency of the system, and at the same time, we need to meet the energy harvesting constraints, user quality of service (QoS) constraints and transmission power constraints. We jointly solve the power allocation, time switching and energy cooperation problems. Because this problem is a nonlinear programming problem, it is difficult to solve directly, so we use the alternating variable method, the iterative algorithm is used to solve the power allocation and time switching problem, and the matching algorithm is used to solve the energy cooperation problem. Simulation results show that the proposed algorithm has obvious advantages in energy efficiency performance compared with the comparison algorithm. At the same time, it is also proved that the introduction of energy cooperation technology can effectively reduce system energy consumption and improve system energy efficiency.

4.
Bioengineered ; 13(3): 5443-5452, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35176940

RESUMO

Reperfusion therapy after acute myocardial infarction can induce myocardial ischemia-reperfusion injury (IRI). Novel evidence has illustrated that N6-methyladenosine (m6A) modification modulates the myocardial IRI progression. Here, our study focuses on the role of m6A methyltransferase fat mass and obesity-associated protein (FTO) in myocardial ischemia/reoxygenation injury and explores potential regulatory mechanisms. Results discovered that FTO down-expressed in myocardial IRI mice and hypoxia/reoxygenation (H/R)-induced cardiomyocytes. Functionally, FTO overexpression attenuated the H/R-induced apoptosis and inflammation of cardiomyocytes. Mechanistically, methylated RNA immunoprecipitation quantitative polymerase chain reaction (MeRIP-qPCR) assay and RIP assay revealed that Yap1 mRNA acted as the target of FTO in cardiomyocytes. Moreover, FTO uninstalled the methylation of Yap1 mRNA, and enforced the stability of Yap1 mRNA. Taken together, our study reveals the role of FTO in H/R-induced myocardial cell injury via m6A-dependent manner, which may provide a new approach to improve myocardial IRI.


Assuntos
Dioxigenase FTO Dependente de alfa-Cetoglutarato , Traumatismo por Reperfusão Miocárdica , Miócitos Cardíacos , Proteínas de Sinalização YAP , Adenosina/metabolismo , Dioxigenase FTO Dependente de alfa-Cetoglutarato/genética , Dioxigenase FTO Dependente de alfa-Cetoglutarato/metabolismo , Animais , Apoptose/genética , Inflamação/genética , Inflamação/metabolismo , Camundongos , Traumatismo por Reperfusão Miocárdica/genética , Traumatismo por Reperfusão Miocárdica/metabolismo , Miócitos Cardíacos/metabolismo , RNA Mensageiro/genética , Proteínas de Sinalização YAP/genética
5.
Am J Transl Res ; 13(5): 4796-4803, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34150060

RESUMO

OBJECTIVE: This paper aims to explore the effects of remifentanil combined with propofol on the stress responses, oxidative damage, and inflammatory responses in cardiac surgery patients. METHODS: One hundred and four patients who underwent cardiac surgery in our hospital from August 2017 to March 2019, were recruited as the study cohort and divided into control and observation groups. The 50 patients in the control group were anesthetized with fentanyl and propofol, and the 54 patients in the observation group were anesthetized with remifentanil and propofol. The general clinical data were observed and compared between the two groups. At different time points, changes in the oxidative stress response indicators (mean artery pressure (MAP) and heart rate (HR)) and in the cardiac function indexes (left ventricular ejection fraction (LVEF), stroke volume (SV), and cardiac output (CO)) were observed. The inflammatory cytokine levels (high-sensitivity C-reactive protein (hs-CRP), interleukin-10 (IL-10), and tumor necrosis factor-α (TNF-α)) were analyzed using enzyme-linked immunosorbent assays (ELISA). The patients' postoperative recovery (time to spontaneous respiration, time to opening eyes, extubation time) and their Visual Analogue Scale (VAS) scores were observed. Their pain at half an hour and at 24 hours after the operation were observed, as well as their postoperative adverse reactions. RESULTS: There were no differences in the general data between the two groups (P>0.05). Compared with the patients in the control group, the patients in the observation group had better oxidative stress levels and better cardiac function indexes (P<0.05), better postoperative inflammatory cytokine levels (P<0.05), better postoperative recovery (P<0.05), lower postoperative pain scores (P<0.05), and a lower total incidence of adverse reactions (P<0.05). CONCLUSION: Remifentanil combined with propofol can effectively reduce oxidative stress and inflammatory responses in cardiac surgery patients.

6.
Front Nutr ; 8: 662357, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34026809

RESUMO

Objective: We aimed to systematically evaluate the association between Dietary Inflammatory Index (DII) and mental health. Methods: We searched PubMed, Embase, and Web of Science from their inception to December 31, 2020. Categorical meta-analysis and dose-response meta-analysis were performed to evaluate the association between DII and mental health. Results: A total of 16 studies were included in this meta-analysis. Compared with the lowest DII category, the highest category was significantly associated with a variety of mental health outcomes, with the following pooled odds ratios (ORs) and 95% confidence intervals (95% CIs): 1.28 (1.17-1.39) for symptoms of depression, 1.27 (1.08-1.49) for symptoms of anxiety, 1.85 (1.43-2.40) for distress, and 4.27 (1.27-14.35) for schizophrenia. Furthermore, there was a linear dose-response relationship between DII and symptoms of depression in that a 1-unit increment in DII was associated with an increased risk of 6% for symptoms of depression (OR: 1.06, 95% CI: 1.03-1.19). Conclusion: The present study indicates that more pro-inflammatory diet, as estimated by the higher DII score, is associated with symptoms of mental disorder. It may be of clinical and public health significance regarding the development of novel nutritional psychiatry approaches to promote good mental health.

7.
Int J Clin Pract ; 75(8): e14159, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33743549

RESUMO

INTRODUCTION: Regional anesthesia might moderate the risk of persistent postsurgical pain, but its effect compared to systemic analgesia is still conflicting. This meta-analysis study was performed to assess the relationship between the efficiency of regional anesthesia versus systemic analgesia in reducing pain persisting longer than 3 months after surgery. METHODS: Through a systematic literature search up to August 2020, 31 studies included 2975 subjects who underwent surgery at baseline and reported a total of 1471 subjects using regional anesthesia and 1319 subjects using conventional anesthesia were found recording relationships between efficiency of regional anesthesia versus systemic analgesia in reducing pain persisting longer than 3 months after surgery. Odds ratio (OR) with 95% confidence intervals (CIs) was calculated between regional anesthesia versus systemic analgesia in reducing pain persisting longer than 3 months after surgery using the dichotomous methods with a random or fixed-effect model. RESULTS: Number of subjects reporting persistent pain 3 months postsurgery was significantly lower in regional anesthesia compared to systemic analgesia in thoracotomy (OR, 0.44; 95% CI, 0.29-0.65, P < .001); breast surgery (OR, 0.46; 95% CI, 0.29-0.72, P < .001); and cesarean section (OR, 0.44; 95% CI, 0.27-0.72, P < .001). CONCLUSIONS: Regional anesthesia might have an independent relationship with lower pain persisting longer than 3 months after thoracotomy, breast surgery, and cesarean section. Further studies are required to validate these findings.


Assuntos
Analgesia , Anestesia por Condução , Anestesia por Condução/efeitos adversos , Anestésicos Locais , Cesárea , Feminino , Humanos , Dor Pós-Operatória/tratamento farmacológico , Dor Pós-Operatória/prevenção & controle , Gravidez
8.
Sensors (Basel) ; 18(11)2018 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-30441871

RESUMO

A joint resource allocation algorithm to minimize the system outage probability is proposed for a decode-and-forward (DF) two-way relay network with simultaneous wireless information and power transfer (SWIPT) under a total power constraint. In this network, the two sources nodes exchange information with the help of a passive relay, which is assumed to help the two source nodes' communication without consuming its own energy by exploiting an energy-harvesting protocol, the power splitting (PS) protocol. An optimization framework to jointly optimize power allocation (PA) at the source nodes and PS at the relay is developed. Since the formulated joint optimization problem is non-convex, the solution is developed in two steps. First, the conditionally optimal PS ratio at the relay node for a given PA ratio is explored; then, the closed-form of the optimal PA in the sense of minimizing the system outage probability with instantaneous channel state information (CSI) is derived. Analysis shows that the optimal design depends on the channel condition and the rate threshold. Simulation results are obtained to validate the analytical results. Comparison with three existing schemes shows that the proposed optimized scheme has the minimum system outage probability.

9.
Sensors (Basel) ; 17(11)2017 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-29137175

RESUMO

This paper considers a wireless energy harvesting two-way relay (TWR) network where the relay has energy-harvesting abilities and the effects of practical hardware impairments are taken into consideration. In particular, power splitting (PS) receiver is adopted at relay to harvests the power it needs for relaying the information between the source nodes from the signals transmitted by the source nodes, and hardware impairments is assumed suffered by each node. We analyze the effect of hardware impairments [-20]on both decode-and-forward (DF) relaying and amplify-and-forward (AF) relaying networks. By utilizing the obtained new expressions of signal-to-noise-plus-distortion ratios, the exact analytical expressions of the achievable sum rate and ergodic capacities for both DF and AF relaying protocols are derived. Additionally, the optimal power splitting (OPS) ratio that maximizes the instantaneous achievable sum rate is formulated and solved for both protocols. The performances of DF and AF protocols are evaluated via numerical results, which also show the effects of various network parameters on the system performance and on the OPS ratio design.

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