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1.
IEEE Trans Cybern ; PP2024 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-38602849

RESUMEN

This article addresses the containment control problem in multiagent systems with nonlinear heterogeneous followers and multiple unknown leaders whose dynamics are exclusively known to their neighbors. The primary goal is to ensure the convergence of each follower to the dynamic convex hull spanned by the leaders under the constraints of limited communication resources. To achieve this, this article introduces a modular event-triggered containment control scheme with three modules. The first module, Module I-signal generator, is designed for each follower to generate a reference signal asymptotically entering the dynamic convex hull without relying on follower dynamics. The second module, Module II-event-triggered mechanism, is tailored to save communication resources effectively by determining when to broadcast information based on perturbed system stability and input-to-state stability theories. The third module, Module III-tracking controller, treats each follower as an independent agent and is crafted to track the reference signal generated by Module I using an output regulation approach. It is established that the system achieves containment control without Zeno behavior under the influence of these modules, and the theoretical results are validated through simulation examples, demonstrating the practical validity of the proposed approach.

2.
Environ Res ; 237(Pt 2): 116995, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37633630

RESUMEN

Green strategy for the preparation of copper oxide nanoparticles (CuO NPs) using table olive has been researched in the present work. Some characterization assays viz., transmission electron microscopy (TEM), X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy-dispersive X-ray (EDX) was used for evaluation of the crystal structure, size and morphology of the manufactured NPs. As a catalyst, the prepared material demonstrated remarkable catalytic capability (>99% in 4 min) for the reduction of rhodamine B using sodium borohydride. In addition, the treated cells with the CuO NPs were examined by regarding the cytotoxicity properties on normal (HUVEC) cell line. The results showed that the prepared CuO NPs did not have any cytotoxicity effects on HUVEC (up to 500 µg/mL). Furthermore, in vivo experiments on burn wounds in rats show that the synthesized CuO NPs ointment significantly diminished (p ≤ 0.01) the wound area. On the other hand, the wound contracture factor was increased in comparison with the control groups. Collectively, the CuO NPs prepared by biological method have potential applications in organic pollutants reduction and wound care applications. In this viewpoint, CuO NPs may be considered as an effective for treatment of different wounds including burn wounds or injuries from surgeries such as plastic surgery.

3.
Front Microbiol ; 14: 1166078, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37234528

RESUMEN

In recent years, the poultry industry had been markedly affected by adenoviral diseases such as hydropericardium syndrome and inclusion body hepatitis caused by fowl adenovirus (FAdV), which have become increasingly prevalent in China. Shandong Province, China, is an important area for poultry breeding where various complex and diverse FAdV serotypes were isolated. However, the dominant strains and their pathogenic characteristics are not yet reported. Therefore, a pathogenicity and epidemiological survey of FAdV was conducted, showing that the local dominant serotypes of FAdV epidemics were FAdV-2, FAdV-4, FAdV-8b, and FAdV-11. Their mortality rates in the 17-day-old specific-pathogen-free (SPF) chicks ranged from 10 to 80%; clinical signs included mental depression, diarrhea, and wasting. The maximum duration of viral shedding was 14 days. The highest incidence in all infected groups was on days 5-9, and then gradual regression occurred thereafter. The most pronounced symptoms occurred in chicks infected with FAdV-4, including pericardial effusion and inclusion body hepatitis lesions. Our results add to the current epidemiological data on FAdV in poultry flocks in Shandong and elucidate the pathogenicity of dominant serotypes. This information may be important for FAdV vaccine development and comprehensive epidemic prevention and control.

4.
IEEE Trans Cybern ; 53(12): 7497-7508, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35552147

RESUMEN

This article aims to develop a virtual-actuator-based control scheme for the consensus tracking problem of multiagent systems (MASs) against actuator faults and mismatched disturbances. The proposed scheme has a double-layer structure. In the cyber layer, the nominal controller is designed with neighboring information for the fault-free case. While in the physical layer, the fault compensator, working as the virtual actuator, is applied to reconfigure faulty plants adaptively. This design enjoys the advantages that the nominal controller needs no adjustment and all its properties can be preserved after failure. Moreover, the proposed control scheme is distinguished by the following features: 1) the commonly imposed rank condition on outage faults is removed; 2) the norm bound of the leader's input is allowed to be unknown even though the topologies are switching and directed; and 3) there is no need to use the estimates of faults in the virtual actuator design, which means the negative impacts caused by the inaccurate fault estimation can be avoided. Finally, a numerical example is given to validate the effectiveness of the theoretical results.

5.
Artículo en Inglés | MEDLINE | ID: mdl-35895652

RESUMEN

This article proposes a distributed consensus tracking controller for a class of nonlinear multiagent systems under a directed graph, in which all agents are subject to time-varying asymmetric full-state constraints, internal uncertainties, and external disturbances. The feasibility condition generally required in the existing constrained control is removed by using the proposed nonlinear mapping function (NMF)-based state reconstruction technology, and the Lipschitz condition usually needed in the consensus tracking is also canceled based on the adaptive command-filtered backstepping framework. The composite learning of the neural network-based function approximator (NN-FAP) and the finite-time smooth disturbance observer (DOB) provides a novel scheme for handling internal and external uncertainties simultaneously. One advantage of this scheme is that the use of online historical data of the closed-loop system strengthens the excitation of NN's learning. Another advantage is that the DOB with NN-FAP embedding realizes that the finite-time observation for external disturbance in the case of the system dynamics is unknown. A complete controller design, sufficient stability analysis, and numerical simulation are provided.

6.
Langmuir ; 37(29): 8789-8800, 2021 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-34255969

RESUMEN

Surfactants can significantly improve the oil recovery of spontaneous imbibition (SI) in unconventional oil reservoirs, but mathematical modeling of surfactant SI for displacing oil in a tight matrix is challenging because of its complex mechanism. Considering the mechanisms of surfactant diffusion and adsorption, the flow equation for the SI of surfactant solution into an oil-saturated capillary is derived, and the dynamic capillary pressure and surfactant concentration during the SI process are characterized. Then, based on the pore size distribution of the pores in a tight matrix, a core-scale mathematical model for SI of surfactant solution into an oil-saturated tight matrix is developed and validated with experimental data from the literature. The results show that surfactant adsorption can increase the product of interfacial tension and the cosine of the contact angle, and the increased capillary pressure in pores leads to a faster imbibition rate. A surfactant with a high adsorption and desorption rate on the water-solid interface and diffusion ability will lead to a higher oil production rate by SI in unconventional oil reservoirs. The proposed model is beneficial for modeling the dynamic process of surfactant SI and screening suitable surfactants for enhanced oil recovery in unconventional reservoirs.

7.
Mol Cell Biochem ; 476(2): 831-839, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33174074

RESUMEN

Rheumatoid arthritis (RA) is a long-standing and growing autoimmune disease. Therefore, the present study was intended to investigate the effect of Corynoline (COR) on CFA induced rheumatoid arthritis in a rat model. Results suggested that COR causes significant reduction in paw swelling, edema, arthritis score, thymus and spleen indexes and neutrophil infiltration (p < 0.01). Moreover, the levels of inflammatory cytokines (interleukin- 1ß, -6, and -17, and TNF-α) and anti-collagen II-specific immunoglobulins (IgG1 and IgG2a) were decreased significantly (p < 0.01) together with increase in antioxidant enzymes (SOD, CAT, and GSH) (p < 0.01) in COR-treated group in dose-dependent manner. In western blot analysis, COR-treated group showed concentration-dependent reduction of expression of COX-2, 5-LOX and NF-p65 as compared to CFA rats. Moreover, COR-treated group showed mild inflammation of cartilage with fewer cartilage erosion and synovititis with most significant reversal of arthritic features in the rats treated with 30 mg/kg. It has been concluded that, COR alleviates oxidative stress and inflammation in arthritic rats, thus verifying its anti-rheumatoid arthritis property.


Asunto(s)
Artritis Reumatoide/tratamiento farmacológico , Alcaloides de Berberina/farmacología , Mediadores de Inflamación/antagonistas & inhibidores , Inflamación/tratamiento farmacológico , Estrés Oxidativo/efectos de los fármacos , Animales , Antioxidantes/farmacología , Artritis Reumatoide/inmunología , Artritis Reumatoide/metabolismo , Artritis Reumatoide/patología , Citocinas/antagonistas & inhibidores , Citocinas/inmunología , Modelos Animales de Enfermedad , Adyuvante de Freund/administración & dosificación , Inflamación/inducido químicamente , Inflamación/metabolismo , Inflamación/patología , Masculino , Ratas , Ratas Sprague-Dawley
8.
ISA Trans ; 99: 123-129, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31558284

RESUMEN

In this paper, fully distributed containment control problems of multi-agent systems with double-integrator dynamics are investigated under directed topologies. For the cases with and without communication delay, two new fully distributed control protocols are designed, which do not need any global information of the communication topology graph. Necessary and sufficient conditions are obtained to ensure the solvability of the considered containment control problems. Particularly, for the case with communication delay, the critical value of the maximum allowable time delay of containment control is found. Finally, numerical simulations are presented to demonstrate the effectiveness of the theoretical results.

9.
IEEE Trans Cybern ; 50(2): 550-560, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30273181

RESUMEN

This paper investigates the distributed containment control problem for a class of general second-order multiagent systems with switched dynamics, which is composed of a continuous-time (CT) subsystem and a discrete-time (DT) subsystem. For this switched multiagent system under fixed directed topology, a distributed containment control protocol is proposed for each follower based on the relative local measurements of neighboring followers and leaders. Some necessary and sufficient conditions are derived under the condition that the network topology contains a directed spanning forest, and these conditions ensure that the general second-order containment control problem can be solved under arbitrary CT-DT switching. If the general second-order system is reduced to the double integrator system, some simpler containment conditions are presented. Furthermore, the similar results are also obtained under switching directed topology. Finally, some simulation examples are presented to show the efficiency of the theoretical results.

10.
Emerg Infect Dis ; 24(2): 384-385, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29350149

RESUMEN

We analyzed demographic and clinical data and estimated the incidence of cysticercosis in Shandong Province, China, during 1975-2014. Our analyses showed that a cysticercosis-endemic area is present in Shandong Province, especially in its western regions. Improved surveillance and control are needed to address the elevated risk for cysticercosis in this region.


Asunto(s)
Cisticercosis/epidemiología , Enfermedades Endémicas , Adolescente , Adulto , Niño , Preescolar , Cisticercosis/diagnóstico , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Adulto Joven
11.
Mol Med Rep ; 16(2): 1837-1845, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28627596

RESUMEN

Curcumin possesses strong anti-inflammatory, anti-rheumatoid and anti-oxidative activities, and has the potential to inhibit nuclear factor­κB (NF­κB) signaling. Cartilage damage in osteoarthritis (OA) is largely mediated by interleukin-1ß (IL-1ß) via activation of various transcription factors, including NF­κB and activator protein­1. The aim of the present study was to determine whether IL­1ß induces matrix metalloproteinase-13 (MMP-13) expression and inhibits type II collagen expression, as well as to examine whether cell proliferation may be inhibited by curcumin through the inhibition of NF­κB signaling. The effects of curcumin were investigated in rat articular chondrocyte cell cultures treated with IL­1ß in the presence or absence of curcumin or the NF­κB inhibitor pyrrolidine dithiocarbamate. Western blotting and reverse transcription­quantitative polymerase chain reaction were conducted to evaluate protein and mRNA expression levels of type II collagen, MMP­13, NF­κB inhibitor α (IκBα), phosphorylated­IκBα and NF­κB subunit p65/RelA. Western blotting and immunofluorescence were performed to examine the effects of curcumin on the expression, phosphorylation and nuclear translocation of NF­κB­associated proteins. The effects of curcumin on cell proliferation were evaluated by Cell Counting Kit­8 (CCK­8). Curcumin was demonstrated to inhibit the IL­1ß­induced activation of NF­κB by suppressing IκBα phosphorylation and p65/RelA nuclear translocation. These events were associated with the downregulation of MMP­13 expression and the upregulation of type II collagen expression, both of which are considered to be NF­κB targets. CCK­8 assays revealed that co­treatment with curcumin resulted in increased proliferation in IL­1ß­treated chondrocytes. These findings implicated curcumin as a naturally occurring anti­inflammatory agent for the treatment of OA via inhibition of NF­κB signaling.


Asunto(s)
Condrocitos/metabolismo , Colágeno Tipo II/metabolismo , Curcumina/farmacología , Interleucina-1beta/metabolismo , Metaloproteinasa 13 de la Matriz/metabolismo , FN-kappa B/metabolismo , Transducción de Señal/efectos de los fármacos , Animales , Núcleo Celular/efectos de los fármacos , Núcleo Celular/metabolismo , Proliferación Celular/efectos de los fármacos , Condrocitos/efectos de los fármacos , Humanos , Inhibidor NF-kappaB alfa/metabolismo , Fosforilación/efectos de los fármacos , Prolina/análogos & derivados , Prolina/farmacología , Transporte de Proteínas/efectos de los fármacos , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ratas , Tiocarbamatos/farmacología , Factor de Transcripción ReIA/metabolismo , Regulación hacia Arriba/efectos de los fármacos
12.
Appl Opt ; 54(5): 1041-5, 2015 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-25968019

RESUMEN

We report on a diode-pumped passively mode-locked Yb:Lu(1.5)Y(1.5)Al(5)O(12) (Yb:LuYAG) laser for the first time to our knowledge. With the mixed crystal of Yb:LuYAG as gain medium, the mode-locked laser generated 2.2 W of average output power with a repetition rate of 83.9 MHz and pulse duration of 2.4 ps at the wavelength of 1030 nm. In order to obtain higher output power, the output from the mode-locked oscillator was further amplified to 8.5 W by two-stage single-pass amplifiers. The high-power picosecond laser is very useful for applications such as pumping of midinfrared optical parametric oscillators, material microprocessing, and UV light generation.

13.
J Arthroplasty ; 29(12): 2289-93, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24412147

RESUMEN

In total hip arthroplasty for the treatment of developmental dysplasia of the hip (DDH) with high hip dislocation, it can be technically challenging to locate the true acetabulum and restore limb length without subtrochantric femoral shortening osteotomy. We explored and described total hip arthroplasty without subtrochanteric femoral shortening osteotomy in 28 hips with Crowe type III and IV dislocation by intravenous injection of rocuronium at 0.9mg/kg 1minute before reduction and hip reduction combined with continuous strong traction of the affected limb with patients in a position with hip and knee flexion. All patients did not show dislocation, prosthesis loosening, and other severe complications. It is thus a safe and feasible reduction technique for arthroplasty of Crowe type III or IV dislocation of DDH.


Asunto(s)
Artroplastia de Reemplazo de Cadera/métodos , Fémur/cirugía , Luxación Congénita de la Cadera/cirugía , Acetábulo/cirugía , Adulto , Artroplastia de Reemplazo de Cadera/efectos adversos , Femenino , Cuello Femoral/cirugía , Prótesis de Cadera , Humanos , Masculino , Persona de Mediana Edad , Osteotomía/métodos , Adulto Joven
14.
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi ; 26(6): 669-71, 677, 2014 Dec.
Artículo en Chino | MEDLINE | ID: mdl-25856897

RESUMEN

OBJECTIVES: To summarize the clinical characteristics of imported falciparum malaria patients and the treatment, so as to provide the evidences for improving the diagnosis and treatment of the disease. METHODS: A total of 138 imported falciparum malaria patients who received the treatment in Shandong Institute of Parasitic Diseases from January 2007 to February 2013 were adopted as the observation subjects, and their clinical data were collected and analyzed. RESULTS: All the 138 patients were back from African countries. The main manifestations were fever, headache, asthenia, and hepatosplenomegaly, and most of them were with decreased RBC, PLT levels and increased LDH levels, and 36.96% of them were misdiagnosed as respiratory diseases, nephritis, hepatitis and so on. Through antimalarial treatment of artemether or artesunate or dihydroartemisinin and primaquine, or dihydroartemisinin and piperaquine, and symptomatic treatment, the short-term and long-term cure rates were 98.55% and 94.93% respectively, with 1 case unrecovered and 1 died. CONCLUSIONS: Artemisinins are still the most effective antimalarial drugs for falciparum malaria. However, some patients recrudesce as the Plasmodium in their body is resistant or insensitive to these drugs. We should pay more attention to the antimalarial and symptomatic treatments in the early stage of severe malaria so as to improve the cure rate.


Asunto(s)
Antimaláricos/uso terapéutico , Malaria Falciparum/tratamiento farmacológico , Plasmodium falciparum/efectos de los fármacos , Adulto , África , Arteméter , Artemisininas/uso terapéutico , Artesunato , China , Errores Diagnósticos , Quimioterapia Combinada , Femenino , Humanos , Malaria Falciparum/diagnóstico , Malaria Falciparum/parasitología , Malaria Falciparum/transmisión , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Viaje , Adulto Joven
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