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1.
J Dig Dis ; 25(1): 61-69, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38408848

RESUMO

OBJECTIVES: Primary biliary cholangitis (PBC) is a chronic autoimmune liver disease that affects the quality of life (QoL) of patients. This study aimed to evaluate the differences in perceptions of PBC among physicians from different hospital departments and patients with PBC. METHODS: An online survey regarding the general knowledge, diagnosis, and management of PBC was completed by physicians and patients. RESULTS: A total of 239 patients with PBC and 239 physicians from eight hospital departments (gastroenterology, infectious diseases, rheumatology, hepatobiliary surgery, pathology, clinical laboratory, ultrasound, and radiology) completed the survey. The results showed that physicians from departments other than gastroenterologists and rheumatologists lacked knowledge of PBC, and that junior gastroenterologists were uncertain about the diagnostic and treatment pathways of PBC. Importantly, the lack of knowledge significantly impacted the QoL of patients, especially the emotional scores of PBC-40 (odds ratio -2.556, 95% confidence interval -3.852 to -1.260, P < 0.001). In addition, there was a perceived knowledge gap between patients and gastroenterologists. CONCLUSIONS: Physicians must improve their awareness of PBC. Patient education and patient-physician communication are important for improving the patient's QoL.


Assuntos
Doenças Autoimunes , Colangite , Gastroenterologistas , Cirrose Hepática Biliar , Humanos , Cirrose Hepática Biliar/diagnóstico , Qualidade de Vida , Inquéritos e Questionários
2.
J Chem Phys ; 160(4)2024 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-38258930

RESUMO

Glass transition, commonly manifested upon cooling a liquid, is continuous and cooling rate dependent. For decades, the thermodynamic basis in liquid-glass transition has been at the center of debate. Here, long-time isothermal annealing was conducted via molecular dynamics simulations for metallic glasses to explore the connection of physical aging in supercooled liquid and glassy states. An anomalous two-step aging is observed in various metallic glasses, exhibiting features of supercooled liquid dynamics in the first step and glassy dynamics in the second step, respectively. Furthermore, the transition potential energy is independent of initial states, proving that it is intrinsic for a metallic glass at a given temperature. We propose that the observed dynamic transition from supercooled liquid dynamics to glassy dynamics could be glass transition manifested isothermally. On this basis, glass transition is no longer cooling rate dependent, but is shown as a clear phase boundary in the temperature-energy phase diagram. Hence, a modified out-of-equilibrium phase diagram is proposed, providing new insights into the nature of glass transition.

3.
Nat Commun ; 14(1): 540, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36725882

RESUMO

How glasses relax at room temperature is still a great challenge for both experimental and simulation studies due to the extremely long relaxation time-scale. Here, by employing a modified molecular dynamics simulation technique, we extend the quantitative measurement of relaxation process of metallic glasses to room temperature. Both energy relaxation and dynamics, at low temperatures, follow a stretched exponential decay with a characteristic stretching exponent ß = 3/7, which is distinct from that of supercooled liquid. Such aging dynamics originates from the release of energy, an intrinsic nature of out-of-equilibrium system, and manifests itself as the elimination of defects through localized atomic strains. This finding is also supported by long-time stress-relaxation experiments of various metallic glasses, confirming its validity and universality. Here, we show that the distinct relaxation mechanism can be regarded as a direct indicator of glass transition from a dynamic perspective.

4.
IEEE Trans Cybern ; 53(3): 1607-1617, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34478397

RESUMO

The problem of enhancing the robust performance of nonlinear fault estimation (FE) is addressed by proposing a novel real-time gain-scheduling mechanism for discrete-time Takagi-Sugeno fuzzy systems. The real-time status of the operating point for the considered nonlinear plant is characterized by using these available normalized fuzzy weighting functions at both the current and the past instants of time. To achieve this, the developed fuzzy real-time gain-scheduling mechanism produces different switching modes by introducing key tunable parameters. Thus, a pair of exclusive FE gain matrices is designed for each switching mode on the strength of time-varying balanced matrices developed in this study, respectively. Since the implementation of more FE gain matrices can be scheduled according to the real-time status of the operating point at each sampling instant, the robust performance of nonlinear FE will be enhanced over the previous methods to a great extent. Finally, considerable numerical comparisons are implemented in order to illustrate that the proposed method is much superior to those existing ones reported in the literature.

5.
IEEE Trans Cybern ; 53(2): 1360-1373, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34982710

RESUMO

This article studies the distributed fault-tolerant bipartite output synchronization problem of discrete-time linear multiagent systems (MASs) with process faults under a general directed signed graph. The reference signal is generated by an autonomous exosystem, which can also be seen as a leader. All followers are divided into two subgroups with antagonistic interactions, and the followers in each subgroup are cooperative. We aim to solve the bipartite fault-tolerant control (FTC) problem via the output regulation theory such that bipartite output synchronization can be achieved in the presence of process faults, that is, the outputs of followers with different subgroups can approach the output of exosystem with the same magnitude and the opposite sign regardless of process faults. To estimate the states and the faults of each follower, a simultaneous state and fault estimator based on the neighboring signed output estimation error and the standard discrete-time algebraic Riccati equation (ARE) is designed. Besides, a new exosystem observer with two classes of convergence conditions relying on the respective solutions of standard and modified AREs is provided. All eigenvalues of the exosystem matrix can lie completely outside the unit circle. Based on these estimations, we present a distributed fault-tolerant output feedback controller, which can overcome the no-loops constraint. Finally, simulation results are given to demonstrate the analytic results.

6.
ISA Trans ; 134: 108-121, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36058719

RESUMO

This paper investigates the distributed robust group output synchronization problem of heterogeneous uncertain linear leader-follower multi-agent systems (MASs), whose followers have nonidentical and parameter uncertain dynamics. To achieve cooperative tracking with multiple targets, a new group synchronization framework based upon the output regulation technique is established. In the underlying directed communication topology, all nonidentical followers are divided into several subgroups. Meanwhile, each subgroup has its output tracking objective generated by an autonomous exosystem which is seen as the leader of each subgroup. Since not all followers can access their exosystems directly, the distributed exosystem observer based on the algebraic Riccati inequality (ARI) is designed to obtain the information of exosystems. Moreover, to compensate for parameter uncertainties for different group topologies, the p-copy internal model is synthesized into distributed control laws, i.e., dynamic state feedback control protocol under an acyclic directed graph and dynamic output feedback control protocol under a general directed graph. It is shown that group synchronization can be respectively achieved with these controllers under acyclic and general partitions regardless of parameter uncertainties. Finally, some examples are provided to verify the validity of the analytic results.

7.
ISA Trans ; 110: 225-237, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33246645

RESUMO

This paper investigates the robust filtering problem for linear uncertain systems affected by noises in restricted frequency intervals. Different from traditional filter schemes, a finite-frequency memory filter is designed to generalize conventional memoryless ones in such a way that a sequence of latest output measurements are employed for current estimation. To be specific, a memory filter is sought which ensures that for all admissible uncertainties, the filtering error system is asymptotically stable with a prescribed noise-attenuation level in the restricted frequency range. To accomplish this, the finite-frequency specification is characterized by the generalized Kalman-Yakubovich-Popov (KYP) lemma, aiming at improving the capability of noise-attenuation over the given frequency range. Moreover, the homogeneous polynomially parameter-dependent technique is adopted to facilitate filter design and reduce conservatism further. Based on the proposed scheme, we prove rigorously that additional past output measurements contribute to less conservative results. Finally, a quarter-car model with an active-suspension system is used to validate the proposed scheme.

8.
Medicine (Baltimore) ; 99(48): e23417, 2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-33235121

RESUMO

BACKGROUND: Gastric cancer (GC) is one of the top 10 malignant tumors worldwide and poses a great threat to human life and health, the prevention and treatment of which has become the focus and difficulty of medical research. With its unique advantages, traditional Chinese medicine (TCM) is widely used in the prevention and treatment of postoperative recurrence and metastasis of GC as well as the improvement of patients' quality of life. The aim of this study is to elucidate the curative effect and the underlying mechanism of Yiqi Huayu Jiedu (YQHYJD) decoction. METHODS/DESIGN: This is a prospective, multicenter, randomized controlled trial continuing 3 years. Two hundred ninety-eight eligible patients will be randomly divided into 2 groups, the chemotherapy combined with placebo and the chemotherapy combined with YQHYJD group at a ratio of 1:1. All patients will receive the treatment for 6 months and follow up for 3 years. The primary outcomes are disease-free survival, and 1-year, 2-year, 3-year progression-free survival rate, while the secondary outcomes are tumor makers, TCM syndrome score, quality of life score, overall chemotherapy completion rate, intestinal flora diversity test, immune function (T, B lymphocyte subsets and NK cells) test. The Security index includes blood, urine and stool routine, electrocardiogram, liver function (ALT), and renal function (BUN, Scr). All of these outcomes will be analyzed at the end of the trial. DISCUSSION: This research will provide the valuable evidence for the efficacy and safety of Yiqi Huayu Jiedu decoction in postoperative GC. Furthermore, it will be helpful to form a higher level of evidence-based medical basis for TCM in the treatment of GC recurrence and metastasis. TRIAL REGISTRATION: ChiCTR2000039038.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Neoplasias Gástricas/tratamento farmacológico , Biomarcadores Tumorais/análise , Quimioterapia Adjuvante , Intervalo Livre de Doença , Microbioma Gastrointestinal , Humanos , Estudos Multicêntricos como Assunto , Metástase Neoplásica/prevenção & controle , Recidiva Local de Neoplasia/prevenção & controle , Intervalo Livre de Progressão , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Neoplasias Gástricas/cirurgia
9.
IEEE Trans Neural Netw Learn Syst ; 30(12): 3735-3747, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30843810

RESUMO

This paper presents a model-free solution to the robust stabilization problem of discrete-time linear dynamical systems with bounded and mismatched uncertainty. An optimal controller design method is derived to solve the robust control problem, which results in solving an algebraic Riccati equation (ARE). It is shown that the optimal controller obtained by solving the ARE can robustly stabilize the uncertain system. To develop a model-free solution to the translated ARE, off-policy reinforcement learning (RL) is employed to solve the problem in hand without the requirement of system dynamics. In addition, the comparisons between on- and off-policy RL methods are presented regarding the robustness to probing noise and the dependence on system dynamics. Finally, a simulation example is carried out to validate the efficacy of the presented off-policy RL approach.

10.
Adv Mater ; 28(46): 10293-10297, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27690333

RESUMO

A multicomponent metallic glass (MG) with highly efficient and anomalous durability for catalyzing water splitting is reported. The outstanding performance of the MG catalyst contributed by self-optimized active sites originates from the intrinsic chemical heterogeneity and selective dealloying on the disordered surface; thus, a new mechanism for improving the durability of catalysts is uncovered.

11.
Asian Pac J Cancer Prev ; 15(23): 10495-500, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25556498

RESUMO

BACKGROUND: To evaluate the effects of bufalin in A549 human lung adenocarcinoma epithelial cells in vitro and assess the underlying mechanisms. MATERIALS AND METHODS: Human A549 non-small cell lung cancer (NSCLC) cells were treated with various concentrations of bufalin. Cell proliferation was measured by CCK-8 assay, apoptotic cell percentage was calculated by flow cytometry and morphological change was observed by inverted phase contrast microscopy/transmission electron microscopy. In addition, the membrane potential of mitochondria was detected by JC-1 fluorescence microscopy assay, and the related protein expression of cytochrome C and caspase-3 was analyzed by Western blotting. RESULTS: Bufalin could inhibit the proliferation of A549 cells via induction of apoptosis, with the evidence of characteristic morphological changes in the nucleus and mitochondria. Furthermore, bufalin decreased the mitochondrial membrane potential with up-regulation of cytochrome C in the cytosol, and activation of caspase-3. CONCLUSIONS: Bufalin inhibits the proliferation of A549 cells and triggers mitochondria-dependent apoptosis, pointing to therapeutic application for NSCLC.


Assuntos
Adenocarcinoma/metabolismo , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Bufanolídeos/farmacologia , Proliferação de Células/efeitos dos fármacos , Neoplasias Pulmonares/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Western Blotting , Caspase 3/efeitos dos fármacos , Caspase 3/metabolismo , Linhagem Celular Tumoral , Citocromos c/efeitos dos fármacos , Citocromos c/metabolismo , Humanos , Microscopia Eletrônica de Transmissão , Microscopia de Fluorescência , Microscopia de Contraste de Fase , Regulação para Cima
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