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1.
Artigo em Inglês | MEDLINE | ID: mdl-38944132

RESUMO

BACKGROUND: There are limited data depicting the prevalence and ramifications of acute limb ischemia (ALI) among cardiogenic shock (CS) patients. METHODS: We employed data from the Cardiogenic Shock Working Group (CSWG), a consortium including 33 sites. We constructed a multi-variable logistic regression to examine the association between clinical factors and ALI, we generated another logistic regression model to ascertain the association of ALI with mortality. RESULTS: There were 7,070 patients with CS and 399 (5.6%) developed ALI. Patients with ALI were more likely to be female (40.4% versus 29.4%) and have peripheral arterial disease (13.8% versus 8.3%). Stratified by maximum SCAI shock stage, the rates of ALI were stage B 0.0%, stage C 1.8%, stage D 4.1%, and stage E 10.3%. Factors associated with higher risk for ALI included: peripheral vascular disease OR 2.24 (95% CI: 1.53 - 3.23; p < 0.01) and ≥ 2 mechanical circulatory support (MCS) devices OR 1.66 (95% CI: 1.24 - 2.21, p < 0.01). ALI was highest for VA-ECMO patients (11.6%) or VA-ECMO + IABP/Impella CP (16.6%) yet use of distal perfusion catheters was less than 50%. Mortality was 38.0% for CS patients without ALI but 57.4% for CS patients with ALI. ALI was significantly associated with mortality, adjusted OR 1.40 (95% CI 1.01 - 1.95, p < 0.01). CONCLUSIONS: The rate of ALI was 6% among CS patients. Factors most associated with ALI include peripheral vascular disease and multiple MCS devices. The downstream ramifications of ALI were dire with a considerably higher risk of mortality.

2.
Neural Netw ; 178: 106402, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38823067

RESUMO

This paper investigates a sliding mode control method for a class of uncertain delayed fractional-order reaction-diffusion memristor neural networks. Different from most existing literature on sliding mode control for fractional-order reaction-diffusion systems, this study constructs a linear sliding mode switching function and designs the corresponding sliding mode control law. The sufficient theory for the globally asymptotic stability of the sliding mode dynamics are provided, and it is proven that the sliding mode surface is finite-time reachable under the proposed control law, with an estimate of the maximum reaching time. Finally, a numerical test is presented to validate the effectiveness of the theoretical analysis.

3.
IEEE Trans Cybern ; PP2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38713575

RESUMO

For the flexible riser systems modeled with partial differential equations (PDEs), this article explores the boundary control problem in depth for the first time using a dynamic event-triggered mechanism (DETM). Given the intrinsic time-space coupling characteristic inherent in PDE computations, implementing a state-dependent DETM for PDE-based flexible risers presents a significant challenge. To overcome this difficulty, a novel dynamic event-triggered control method is introduced for flexible riser systems, focusing on optimizing available control inputs. In order to save computational costs from the controller to the actuator, a dynamic event-triggered adaptive boundary controller is designed to effectively reduce boundary position vibrations. Additionally, considering external disturbances, an adaptive bounded compensation term is incorporated to counteract the influence of external disturbances on the system. Addressing boundary position constraints, a new integral barrier Lyapunov function (iBLF) tailored specifically for flexible riser systems is introduced, thereby alleviating conservatism in the controller design of flexible risers modeled by PDEs. At last, the validity of the proposed method is demonstrated through a simulation example.

4.
Artigo em Inglês | MEDLINE | ID: mdl-38536697

RESUMO

This article addresses the finite-time neural predefined performance control (PPC) issue for state-constrained nonlinear systems (NSs) with exogenous disturbances. By integrating the predefined-time performance function (PTPF) and the conventional barrier Lyapunov function (BLF), a new set of time-varying BLFs is designed to constrain the error variables. This establishes conditions for satisfying full-state constraints while ensuring that the tracking error meets the predefined performance indicators (PPIs) within a predefined time. Additionally, the incorporation of the nonlinear disturbance observer technique (NDOT) in the control design significantly enhances the ability of the system to reject disturbances and improves overall robustness. Leveraging recursive design based on dynamic surface control (DSC), a finite-time neural adaptive PPC strategy is devised to ensure that the closed-loop system is semi-globally practically finite-time stable (SPFS) and achieves the desired PPIs. Finally, the simulation results of two practical examples validate the efficacy and viability of the proposed approach.

5.
ISA Trans ; 147: 22-35, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38311496

RESUMO

This article investigates the stabilization issue of highly non-linear hybrid stochastic delayed networks (HSDNs) via periodic self-triggered control under impulse (PS-TCI). Firstly, the existence of a unique global solution for highly non-linear HSDNs under PS-TCI is studied. Then, a stabilization criterion for highly non-linear HSDNs is established, by combining a graph-theoretic approach with a novel Lyapunov-based analysis, based on a 'genuine' Lyapunov function defined by introducing an auxiliary timer. Therein, the less conservative polynomial growth condition and local Lipschitz condition for the drift and diffusion coefficients are used than the linear growth condition and global Lipschitz condition. Meanwhile, the design idea of PS-TCI is based on the evolution of an upper bound of the mathematical expectation for Lyapunov function (not directly Lyapunov function or system state), which implies that the triggered instant of PS-TCI is not a random variable. Finally the theoretical results are employed to study the stability of a class of FitzHugh-Nagumo circuits networks and the central pattern generators networks of a hexapod robot, and correlative numerical simulations are provided for demonstration.

6.
IEEE Trans Cybern ; 54(3): 1768-1781, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37030788

RESUMO

When there is a sudden load disturbance in an islanded microgrid, the peer-to-peer control model requires the energy resource to maintain a margin of generation, resulting in a relatively limited regulation range, that is, voltage/frequency sometimes requires additional control to maintain stability. A "source-storage-load" coordinated master-slave control strategy is proposed in this study to address the aforementioned issues. The system voltage and frequency will be stable as long as the output frequency and voltage of the master resource are stable. Furthermore, it can fully utilize the power supply capacity of resources to support the supply-demand balance. The following tasks are included in the proposed strategy: 1) to improve the operational security in the face of load disruption, a source-storage-load coordinated control method based on the "ramping speed" ratio is proposed, which can quickly restore the balance of supply and demand; 2) to improve the communication reliability in the face of interruption, a channel planning method is proposed, which can address the communication interruption problem by constructing an internal network among source-storage-load; and 3) to improve the mode switching stability of resources subjected to external disturbance, the external disturbance suppression and stability analysis involved in the regulation process are completed using sliding-mode control and small signal model methods. Related case studies are carried out to verify the effectiveness of the proposed strategies.

7.
Am J Health Syst Pharm ; 81(5): e115-e121, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-37952169

RESUMO

PURPOSE: The Impella device historically required a heparin-based purge solution to reduce the risk of biomaterial deposition to maintain pump function. In April 2022, the Food and Drug Administration approved utilization of bicarbonate-based purge solutions (BBPS) as an alternative to heparin for patients who are intolerant to heparin or in whom heparin is contraindicated. The purpose of this case series is to report patient outcomes of Impella support with BBPS use at our institution. SUMMARY: Eighteen patients who received BBPS via the Impella CP or Impella 5.5 device were included in our review. Patients were included if they had BBPS administration for greater than 24 hours. All patients were followed for 72 hours after cessation of BBPS. Indications for BBPS were coagulopathy (n = 5, 28%), suspected HIT (n = 2, 11%), confirmed HIT (n = 1, 6%), and major bleeding (n = 10, 56%). Three patients (17%) experienced an Impella complication while on BBPS. One patient required pump exchange, one required removal of the Impella device, and one received alteplase for suspected purge block. Of these, two patients experienced complications greater than 21 days into BBPS therapy. CONCLUSION: This case series adds to the literature describing clinical outcomes for patients on Impella support with BBPS. While BBPS offers a viable option for the management of patients on Impella devices who are unable to tolerate heparin-based purge solutions, further data is needed to determine the longevity of the Impella device with BBPS to minimize risk of Impella complications.


Assuntos
Anticoagulantes , Coração Auxiliar , Humanos , Bicarbonatos , Coração Auxiliar/efeitos adversos , Choque Cardiogênico/etiologia , Heparina/efeitos adversos , Resultado do Tratamento , Estudos Retrospectivos
8.
IEEE Trans Cybern ; 54(3): 1972-1983, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37738198

RESUMO

This article proposes a novel event-triggered second-order sliding mode (SOSM) control algorithm using the small-gain theorems. The developed algorithm has global event property in aspects of the triggering time intervals. First, an SOSM controller is designed related to the sampling error of states, and it is proved that the closed-loop system is finite-time input-to-state stable (FTISS) with the sampling error via utilizing the small-gain theorems. Second, combined with the constructed SOSM controller, a new triggering mechanism is proposed depending on the sampling error by designing the appropriate FTISS gain condition. Third, the practical finite-time stability of the closed-loop system is verified. It is shown that the minimum triggering time interval is always a positive value in the whole state space. Finally, the simulation results demonstrate the effectiveness of the developed control method.

9.
J Card Fail ; 30(4): 564-575, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37820897

RESUMO

BACKGROUND: Consensus recommendations for cardiogenic shock (CS) advise transfer of patients in need of advanced options beyond the capability of "spoke" centers to tertiary/"hub" centers with higher capabilities. However, outcomes associated with such transfers are largely unknown beyond those reported in individual health networks. OBJECTIVES: To analyze a contemporary, multicenter CS cohort with the aim of comparing characteristics and outcomes of patients between transfer (between spoke and hub centers) and nontransfer cohorts (those primarily admitted to a hub center) for both acute myocardial infarction (AMI-CS) and heart failure-related HF-CS. We also aim to identify clinical characteristics of the transfer cohort that are associated with in-hospital mortality. METHODS: The Cardiogenic Shock Working Group (CSWG) registry is a national, multicenter, prospective registry including high-volume (mostly hub) CS centers. Fifteen U.S. sites contributed data for this analysis from 2016-2020. RESULTS: Of 1890 consecutive CS patients enrolled into the CSWG registry, 1028 (54.4%) patients were transferred. Of these patients, 528 (58.1%) had heart failure-related CS (HF-CS), and 381 (41.9%) had CS related to acute myocardial infarction (AMI-CS). Upon arrival to the CSWG site, transfer patients were more likely to be in SCAI stages C and D, when compared to nontransfer patients. Transfer patients had higher mortality rates (37% vs 29%, < 0.001) than nontransfer patients; the differences were driven primarily by the HF-CS cohort. Logistic regression identified increasing age, mechanical ventilation, renal replacement therapy, and higher number of vasoactive drugs prior to or within 24 hours after CSWG site transfer as independent predictors of mortality among HF-CS patients. Conversely, pulmonary artery catheter use prior to transfer or within 24 hours of arrival was associated with decreased mortality rates. Among transfer AMI-CS patients, BMI > 28 kg/m2, worsening renal failure, lactate > 3 mg/dL, and increasing numbers of vasoactive drugs were associated with increased mortality rates. CONCLUSION: More than half of patients with CS managed at high-volume CS centers were transferred from another hospital. Although transfer patients had higher mortality rates than those who were admitted primarily to hub centers, the outcomes and their predictors varied significantly when classified by HF-CS vs AMI-CS.


Assuntos
Insuficiência Cardíaca , Infarto do Miocárdio , Humanos , Choque Cardiogênico/diagnóstico , Choque Cardiogênico/epidemiologia , Choque Cardiogênico/terapia , Centros de Atenção Terciária , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/terapia , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/epidemiologia , Infarto do Miocárdio/terapia , Hospitalização , Mortalidade Hospitalar
10.
Pol J Vet Sci ; 26(4): 635-646, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38088307

RESUMO

Airway remodeling is a major pathological characteristic of chronic obstructive pulmonary disease (COPD). This study aimed to investigate the effect of Abhd2 deficiency on ovalbumin (OVA)-induced airway remodeling and inflammation in vivo. Abhd2-deficient mice were used to establish an OVA-induced asthma model. Lung tissues were analyzed using hematoxylin and eosin (HE) staining, Masson staining, immunohistochemistry, quantitative reverse transcription- polymerase chain reaction (qRT-PCR), and western blotting were used to determine the role of Abhd2 in the regulation of OVA-induced airway remodeling and inflammation. Our findings revealed that the RNA expression of inflammatory factors, including IL-1ß, IL-6, IL-4, and IL-13, was significantly increased in OVA-induced Abhd2 Gt/Gt asthmatic mice. The expression of IFN-γ was decreased significantly in OVA-induced Abhd2 Gt/Gt asthmatic mice. The protein expression of airway remodeling factors, including α-SMA, type I collagen, and Ki67, was also increased in OVA-induced Abhd2 Gt/Gt asthmatic mice compared to that in OVA-induced wild-type (WT) mice. Additionally, Abhd2 deficiency promoted the expression of p-Akt in tissues of the asthma model. These results suggest that Abhd2 deficiency exacerbates airway remodeling and inflammation through the PI3K/Akt pathway in chronic asthma.


Assuntos
Asma , Animais , Camundongos , Remodelação das Vias Aéreas , Asma/induzido quimicamente , Asma/genética , Asma/veterinária , Líquido da Lavagem Broncoalveolar , Modelos Animais de Doenças , Inflamação/metabolismo , Inflamação/veterinária , Pulmão , Camundongos Endogâmicos BALB C , Ovalbumina/toxicidade , Ovalbumina/metabolismo , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo
11.
Zhonghua Wei Chang Wai Ke Za Zhi ; 26(12): 1171-1178, 2023 Dec 25.
Artigo em Chinês | MEDLINE | ID: mdl-38110279

RESUMO

Objective: To investigate the impact of relative locations of multiple foci and microsatellite status of sporadic, synchronous, multiple, primary, colorectal carcinomas on clinicopathological features and prognosis. Methods: The clinicopathologic and prognostic data of 278 patients with sporadic, synchronous, multiple, primary, colorectal carcinomas who had been admitted to the Department of Colorectal Surgery at Zhejiang Cancer Hospital from January 2008 to July 2022 were retrospectively collected. The patients were categorized into three groups based on the relative locations of their multiple cancer foci: (1) a right-sided group that comprised patients with multiple cancer foci in the cecum, ascending colon, hepatic flexure of the colon, and transverse colon; (2) a left-sided group that comprised patients with multiple cancer foci in the splenic flexure of the colon, descending colon, sigmoid colon, and rectum; and (3) a left- and right-sided group that comprised patients with multiple cancer foci in the right half of the colon and left half of the colon/rectum. Additionally, the patients were further divided into two groups based on microsatellite status: a high microsatellite instability (MSI-H) and a low MSI/stable MSI (MSI/L&MSS) group. We compared differences in clinical characteristics and prognostic indicators between these groups. The χ2 test was utilized to compare selected clinical characteristics, whereas Kaplan-Meier survival analyses and log-rank tests were performed to compare their effects on prognosis. Result: Among 278 patients with SSCRC, 256 (92.1%) presented with two cancer foci and 22 (7.9%) with more than two foci. Additionally, 255 patients (91.7%) had adenocarcinomas, whereas the remaining 23 (8.3%) had mucinous adenocarcinomas. Lymph node metastases were identified in 136 patients (48.9%); the cancer foci had infiltrated beyond the muscular layer in 238 (85.6%); and 147 patients (52.9%) were diagnosed with TNM Stage III-IV disease. There were 155 patients (55.8%) in the left-sided group, 55 (19.8%) in the right-sided group, and 68 (24.5%) in the left- and right-sided group. Immunohistochemical examination of all four mismatch repair proteins were performed in 199 cases, revealing that 166 of these patients had MSI/L&MSS and 33 MSI-H disease. In the left-sided, left- and right-sided, and right-sided groups, the proportion of women was 16.8% (26/155), 26.5% (18/68), and 49.1% (27/55), respectively; these differences are statistically significant (χ2=22.335, P<0.001). The proportions of patients with more than three cancer foci were 5.2% (8/155), 16.2% (11/68), and 5.5% (3/55), respectively; these differences are statistically significant (χ2=8.438, P=0.015). The proportions of mucinous adenocarcinomas were 4.5% (7/155), 8.8% (6/68), and 18.2% (10/55), respectively; these differences are statistically significant (χ2=10.026, P=0.007). The proportions of patients with lymph node metastases were 55.5% (86/155), 48.5% (33/68), and 30.9% (17/55); these differences are statistically significant (χ2=9.817, P=0.007). The proportions of patients with Stage T3 & T4 disease in each group according to location were 81.3% (126/155), 88.2% (60/68), and 94.5% (52/55), respectively; these differences are statistically significant (χ2=6.293,P=0.043). The proportions of TNM Stage III-IV tumors were 59.4% (92/155), 54.4% (37/68), and 32.7% (18/55), respectively; these differences are statistically significant (χ2=11.637, P=0.003). Age, size of cancer foci, presence of distant metastasis, adenoma, nerve invasion, and vascular invasion did not differ significantly between the three groups (all P>0.05). Compared with those with MSI-H, patients with MSI/L&MSS disease were more likely to be aged >65 years and male (50.6% [84/166] vs. 15.2% [5/33], χ2=13.994,P<0.001; 80.7% [134/166] vs. 54.5% [18/33], χ2=10.457,P=0.001), more likely to be in the left-sided group (63.3% [105/166] vs. 24.2% [8/33], χ2=18.232, P<0.001), had a higher proportion of cancer foci of diameter <4 cm (54.8% [91/166] vs. 33.3% [11/33], χ2=5.086,P=0.024), and a lower proportion of mucinous adenocarcinomas (4.2% [7/166] vs. 27.3% [9/33], χ2=19.791,P<0.001), more likely to develop distant metastases (22.3% [37/166] vs. 6.1% [2/33], χ2=4.601,P=0.032), more likely to have lymph node metastases (57.2% [95/166) vs. 24.2% [8/33], χ2=11.996,P<0.001) and nerve invasion (28.9% [48/166] vs. 6.1% [2/33], χ2=7.643, P=0.006), had a higher proportion of TNM Stage III-IV disease (60.2% [100/166] vs. 24.2% [8/33], χ2=14.374, P<0.001), and a smaller proportion of family history of tumors (28.9% [48/166] vs. 60.6% [20/33], χ2=12.228, P<0.001). All the above-listed differences are statistically significant (all P<0.05). The differences in number of cancer foci, depth of infiltration, presence or absence of adenomas, and vascular invasion were not statistically significant (all P>0.05). In the 33 patients with MSI-H status and mismatch repair protein loss, the highest frequency of deletion was found in PMS-2 (66.7%, 22/33), followed by MLH-1 (57.6%, 19/33), whereas the proportions of MSH-2 (33.3%, 11/33) and MSH-6 (24.2%, 8/33) deletions were relatively low. There were statistically significant differences in the 3-year overall survival rates among the groups according to relative locations of cancer foci. The 3-year overall survival rates were 96.8%, 79.6%, and 88.5% in the right-sided, left- and right-sided, and left-sided groups, respectively (P=0.021). As to microsatellite status, the 3-year overall survival rate of patients with MSI-H disease was 93.8%, which is significantly better than the 78.4% for those with MSI/L & MSS (P=0.026). Conclusions: Among sporadic, synchronous, multiple, primary, colorectal carcinomas, those with right-sided disease had the deepest local infiltration, whereas those with left-sided disease had the greatest number of lymph node metastases, most advanced clinical TNM stage, lowest percentage of MSI-H disease, and the poorest prognosis.


Assuntos
Adenocarcinoma Mucinoso , Neoplasias Colorretais , Neoplasias Primárias Múltiplas , Humanos , Masculino , Feminino , Neoplasias Colorretais/patologia , Metástase Linfática , Estudos Retrospectivos , Prognóstico , Instabilidade de Microssatélites , Neoplasias Primárias Múltiplas/genética
12.
JACC Heart Fail ; 11(12): 1742-1753, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37930289

RESUMO

BACKGROUND: Studies reporting cardiogenic shock (CS) outcomes in women are scarce. OBJECTIVES: The authors compared survival at discharge among women vs men with CS complicating acute myocardial infarction (AMI-CS) and heart failure (HF-CS). METHODS: The authors analyzed 5,083 CS patients in the Cardiogenic Shock Working Group. Propensity score matching (PSM) was performed with the use of baseline characteristics. Logistic regression was performed for log odds of survival. RESULTS: Among 5,083 patients, 1,522 were women (30%), whose mean age was 61.8 ± 15.8 years. There were 30% women and 29.1% men with AMI-CS (P = 0.03). More women presented with de novo HF-CS compared with men (26.2% vs 19.3%; P < 0.001). Before PSM, differences in baseline characteristics and sex-specific outcomes were seen in the HF-CS cohort, with worse survival at discharge (69.9% vs 74.4%; P = 0.009) and a higher rate of maximum Society for Cardiac Angiography and Interventions stage E (26% vs 21%; P = 0.04) in women than in men. Women were less likely to receive pulmonary artery catheterization (52.9% vs 54.6%; P < 0.001), heart transplantation (6.5% vs 10.3%; P < 0.001), or left ventricular assist device implantation (7.8% vs 10%; P = 0.01). Regardless of CS etiology, women had more vascular complications (8.8% vs 5.7%; P < 0.001), bleeding (7.1% vs 5.2%; P = 0.01), and limb ischemia (6.8% vs 4.5%; P = 0.001). More vascular complications persisted in women after PSM (10.4% women vs 7.4% men; P = 0.06). CONCLUSIONS: Women with HF-CS had worse outcomes and more vascular complications than men with HF-CS. More studies are needed to identify barriers to advanced therapies, decrease complications, and improve outcomes of women with CS.


Assuntos
Insuficiência Cardíaca , Infarto do Miocárdio , Masculino , Humanos , Feminino , Pessoa de Meia-Idade , Idoso , Choque Cardiogênico/etiologia , Choque Cardiogênico/terapia , Insuficiência Cardíaca/complicações , Insuficiência Cardíaca/terapia , Infarto do Miocárdio/complicações , Infarto do Miocárdio/terapia , Angiografia Coronária , Mortalidade Hospitalar
13.
Neural Netw ; 167: 763-774, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37729790

RESUMO

In this paper, the exponential consensus of leaderless and leader-following multi-agent systems with Lipschitz nonlinear dynamics is illustrated with aperiodic sampled-data control using a two-sided loop-based Lyapunov functional (LBLF). Firstly, applying input delay approach to reformulate the resulting sampled-data system as a continuous system with time-varying delay in the control input. A two-sided LBLF which captures the information on sampled-data pattern is constructed and the symmetry of the Laplacian matrix together with Newton-Leibniz formula have been employed to obtain reduced number of decision variables and decreased LMI dimensions for the exponential sampled-data consensus problem. Subsequently, an aperiodic sampled-data controller was designed to simplify and enhance stability conditions for computation and optimization purposes in the proposed approach. Finally, based on the controller design, simulation examples including the power system are proposed to illustrate the theoretical analysis, moreover, a larger sampled-data interval can be acquired by this method than other literature, thereby conserving bandwidth and reducing communication resources.


Assuntos
Algoritmos , Dinâmica não Linear , Consenso , Simulação por Computador , Comunicação
14.
Artigo em Inglês | MEDLINE | ID: mdl-37561622

RESUMO

This work investigates the protocol-based synchronization of inertial neural networks (INNs) with stochastic semi-Markovian jumping parameters and image encryption application. The semi-Markovian jumping process is adopted to characterize INNs under sudden complex changes. To conserve the limited available network bandwidth, an adaptive event-driven protocol (AEDP) is developed in the corresponding semi-Markovian jumping INNs (S-MJINNs), which not only reduces the amount of data transmission but also avoids the Zeno phenomenon. The objective is to construct an adaptive event-driven controller so that the drive and response systems maintain synchronous relationships. Based on the appropriate Lyapunov functional, integral inequality, and free weighting matrix, novel criteria are derived to realize the synchronization. Moreover, the desired adaptive event-driven controller is designed under a semi-Markovian jumping process. The proposed method is demonstrated through a numerical example and an image encryption process.

15.
Neural Netw ; 165: 213-227, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37307665

RESUMO

In this paper, the stochastic sampled-data exponential synchronization problem for Markovian jump neural networks (MJNNs) with time-varying delays and the reachable set estimation (RSE) problem for MJNNs subjected to external disturbances are investigated. Firstly, assuming that two sampled-data periods satisfy Bernoulli distribution, and introducing two stochastic variables to represent the unknown input delay and the sampled-data period respectively, the mode-dependent two-sided loop-based Lyapunov functional (TSLBLF) is constructed, and the conditions for the mean square exponential stability of the error system are derived. Furthermore, a mode-dependent stochastic sampled-data controller is designed. Secondly, by analyzing the unit-energy bounded disturbance of MJNNs, a sufficient condition is proved that all states of MJNNs are confined to an ellipsoid under zero initial condition. In order to make the target ellipsoid contain the reachable set of the system, a stochastic sampled-data controller with RSE is designed. Eventually, two numerical examples and an analog resistor-capacitor network circuit are provided to show that the textual approach can obtain a larger sampled-data period than the existing approach.


Assuntos
Redes Neurais de Computação , Simulação por Computador , Cadeias de Markov , Processos Estocásticos , Fatores de Tempo
16.
Med Oral Patol Oral Cir Bucal ; 28(6): e525-e529, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37330963

RESUMO

BACKGROUND: Reactive cutaneous capillary endothelial proliferation (RCCEP), a special adverse event (AE) only observed in patients treated with camrelizumab, was reported to be correlated with the efficacy of camrelizumab in patients with advanced hepatocellular carcinoma. This study to analyze the possible correlation between the occurrence of RCCEP and efficacy of camrelizumab in patients with recurrent/metastatic head and neck squamous cell carcinoma (R/M HNSCC). MATERIAL AND METHODS: In this study, we retrospectively analyzed the efficacy and RCCEP occurrence of camrelizumab in 58 patients with R/M HNSCC in the Shanghai Ninth People's Hospital affiliated to Shanghai JiaoTong University School of Medicine between January 2019 and June 2022. Kaplan-Meier analysis was used to assess the correlation between the occurrence of RCCEP and the survival of enrolled patients, and COX multifactor analysis was adopted to evaluate associated factors that affected the efficacy of camrelizumab immunotherapy. RESULTS: A significant correlation between the incidence of RCCEP and a higher objective response rate was observed in this study (p=0.008). The occurrence of RCCEP was associated with better median overall survival (17.0 months vs. 8.7 months, p<0.0001, HR=5.944, 95% CI:2.097-16.84) and better median progression-free survival (15.1 months vs. 4.0 months, p<0.0001, HR=4.329,95% CI:1.683-11.13). In COX multifactor analysis, RCCEP occurrence was also an independent prognostic factor affecting OS and PFS in patients with R/M HNSCC. CONCLUSIONS: The occurrence of RCCEP can show a better prognosis, it could be used as a clinical biomarker to predict the efficacy of camrelizumab treatment.


Assuntos
Neoplasias de Cabeça e Pescoço , Recidiva Local de Neoplasia , Carcinoma de Células Escamosas de Cabeça e Pescoço , Humanos , Proliferação de Células , China , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/epidemiologia , Recidiva Local de Neoplasia/tratamento farmacológico , Estudos Retrospectivos , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Carcinoma de Células Escamosas de Cabeça e Pescoço/epidemiologia
17.
JACC Heart Fail ; 11(10): 1304-1315, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37354148

RESUMO

BACKGROUND: Cardiogenic shock (CS) patients remain at 30% to 60% in-hospital mortality despite therapeutic innovations. Heterogeneity of CS has complicated clinical trial design. Recently, 3 distinct CS phenotypes were identified in the CSWG (Cardiogenic Shock Working Group) registry version 1 (V1) and external cohorts: I, "noncongested;" II, "cardiorenal;" and III, "cardiometabolic" shock. OBJECTIVES: The aim was to confirm the external reproducibility of machine learning-based CS phenotypes and to define their clinical course. METHODS: The authors included 1,890 all-cause CS patients from the CSWG registry version 2. CS phenotypes were identified using the nearest centroids of the initially reported clusters. RESULTS: Phenotypes were retrospectively identified in 796 patients in version 2. In-hospital mortality rates in phenotypes I, II, III were 23%, 41%, 52%, respectively, comparable to the initially reported 21%, 45%, and 55% in V1. Phenotype-related demographic, hemodynamic, and metabolic features resembled those in V1. In addition, 58.8%, 45.7%, and 51.9% of patients in phenotypes I, II, and III received mechanical circulatory support, respectively (P = 0.013). Receiving mechanical circulatory support was associated with increased mortality in cardiorenal (OR: 1.82 [95% CI: 1.16-2.84]; P = 0.008) but not in noncongested or cardiometabolic CS (OR: 1.26 [95% CI: 0.64-2.47]; P = 0.51 and OR: 1.39 [95% CI: 0.86-2.25]; P = 0.18, respectively). Admission phenotypes II and III and admission Society for Cardiovascular Angiography and Interventions stage E were independently associated with increased mortality in multivariable logistic regression compared to noncongested "stage C" CS (P < 0.001). CONCLUSIONS: The findings support the universal applicability of these phenotypes using supervised machine learning. CS phenotypes may inform the design of future clinical trials and enable management algorithms tailored to a specific CS phenotype.


Assuntos
Insuficiência Cardíaca , Choque Cardiogênico , Humanos , Insuficiência Cardíaca/complicações , Estudos Retrospectivos , Reprodutibilidade dos Testes , Progressão da Doença , Mortalidade Hospitalar
18.
ISA Trans ; 140: 266-278, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37301648

RESUMO

This paper investigates the teleoperation problem of networked disturbed mobile manipulators (NDMMs), in which the human operator remotely controls multiple slave mobile manipulators through a master manipulator. Each individual of the slave ones consisted of a nonholonomic mobile platform and a holonomic constrained manipulator that is mounted on the nonholonomic mobile platform. The cooperative control objective of the considered teleoperation problem includes: (1) synchronizing the states of the slave manipulators to the human-controlled master one; (2) forcing the mobile platforms of the slave ones to form a user-defined formation; (3) controlling the geometric center of all the platforms to track a reference trajectory. We present a hierarchical finite-time cooperative control (HFTCC) framework to achieve the cooperative control goal in a finite time. The presented framework includes the distributed estimator, the weight regulator and the adaptive local controller, where the estimator generates the estimated states of the desired formation and trajectory, the regulator selects the slave robot that the master one needs to track, as well as the presented adaptive local controller guarantees the finite-time convergence of the controlled states with model uncertainties and disturbances. Additionally, for improving the telepresence, a novel super twisting observer is presented to reconstruct the interaction force between the salve mobile manipulators and the remote operating environment on the master (i.e., the human) side. Finally, the effectiveness of the proposed control framework is demonstrated by several simulation results.

19.
IEEE Trans Cybern ; 53(6): 4043-4053, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37015618

RESUMO

This study is devoted to event-triggered fuzzy load frequency control (LFC) for wind power systems (WPSs) with measurement outliers and transmission delays. Due to the integration of wind turbine (WT) with nonlinearity, the T-S fuzzy model of WPS is established for stability analysis and controller design. To mitigate the network burden, a new sampled memory-event-triggered mechanism (SMETM) related to historical system information is presented. It has the following two merits: 1) the utilization of continuous memory outputs over a given interval is useful to reduce the information loss in the period of samples and the redundant triggering events induced by disturbances and noises and 2) an extra upper constraint is added in the triggering condition to generate a new event only when the error signal belongs to a bounded range, thus, the false events caused by measurement outliers can be differentiated out and then be dropped. By representing the memory signal with transmission delay as a time-varying distributed delay term, a T-S fuzzy time-varying distributed delay system is built up to model the H∞ LFC WPS. With the help of the Lyapunov method and the integral inequality relying on distributed delay, some criteria are derived to solve the triggering matrix and fuzzy controllers. Finally, the merits of the proposed SMETM are tested by simulation results.

20.
Artigo em Inglês | MEDLINE | ID: mdl-37028289

RESUMO

This article investigates the distributed leader-following consensus for a class of nonlinear stochastic multiagent systems (MASs) under directed communication topology. In order to estimate unmeasured system states, a dynamic gain filter is designed for each control input with reduced filtering variables. Then, a novel reference generator is proposed, which plays a key role in relaxing the restriction on communication topology. Based on the reference generators and filters, a distributed output feedback consensus protocol is proposed by a recursive control design approach, which incorporates adaptive radial basis function (RBF) neural networks to approximate the unknown parameters and functions. Compared with existing works on stochastic MASs, the proposed approach can significantly reduce the number of dynamic variables in filters. Furthermore, the agents considered in this article are quite general with multiple uncertain/unmatched inputs and stochastic disturbance. Finally, a simulation example is given to demonstrate the effectiveness of our results.

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