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1.
ISA Trans ; 145: 19-31, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38057171

ABSTRACT

This paper investigates the problem of event-triggered mechanism(ETM)-based sliding-mode fault-tolerant control (FTC) for a six-rotor Unmanned Aerial Vehicle (UAV) with dead zone input (DZI) cases, considering potential actuator and sensor faults. Initially, a dynamic ETM is designed, followed by the development of a non-fragile observer utilizing this designed ETM. An integral sliding surface (SS) is then designed in the observation space, and the system is augmented and treated as a variable time delay system. Subsequently, sufficient conditions to ensure the stability of the augmented system with an H∞ performance index γ are obtained using the Lyapunov-Krasovskii function. Next, a sliding mode control (SMC) law is formulated to guide the sliding variables to the SS in finite time. Furthermore, sufficient conditions for ensuring system stability with an H∞ performance index γ are decoupled, and the calculation methods for the non-fragile observer gain matrix and the sliding mode gain matrix are obtained. Finally, to validate the effectiveness of the proposed method in this paper, simulation experiments are conducted.

2.
Molecules ; 28(9)2023 Apr 30.
Article in English | MEDLINE | ID: mdl-37175244

ABSTRACT

A facile hydrothermal process has been developed to synthesize the α-Fe2O3 nanowire arrays with a preferential growth orientation along the [110] direction. The W/α-Fe2O3/FTO memory device with the nonvolatile resistive switching behavior has been achieved. The resistance ratio (RHRS/RLRS) of the W/α-Fe2O3/FTO memory device exceeds two orders of magnitude, which can be preserved for more than 103s without obvious decline. Furthermore, the carrier transport properties of the W/α-Fe2O3/FTO memory device are dominated by the Ohmic conduction mechanism in the low resistance state and trap-controlled space-charge-limited current conduction mechanism in the high resistance state, respectively. The partial formation and rupture of conducting nanofilaments modified by the intrinsic oxygen vacancies have been suggested to be responsible for the nonvolatile resistive switching behavior of the W/α-Fe2O3/FTO memory device. This work suggests that the as-prepared α-Fe2O3 nanowire-based W/α-Fe2O3/FTO memory device may be a potential candidate for applications in the next-generation nonvolatile memory devices.

3.
Prog Biophys Mol Biol ; 177: 229-234, 2023 01.
Article in English | MEDLINE | ID: mdl-36574883

ABSTRACT

As a noninvasive method, circulating tumor cell (CTC) provides ideal liquid biopsy specimens for early cancer screening and diagnosis. CTCs detection in breast cancer is correlated with patient prognosis such as disease-free survival (DFS) and overall survival (OS). Besides, accumulating evidence supported that CTCs count may be indicator for chemotherapy response as well. The functional roles of microRNA (miRNA) in breast cancer have been well-recognized for the last few years. Due to its stability in circulation, numerous studies have proven that circulating miRNA may serve as promising diagnostic and prognostic biomarkers in breast cancer. The potential ability of miRNAs in disease screening, staging or even molecular subtype classification makes them valuable tools for early breast cancer patients. It would be of great significance to characterize the miRNA expression profile in CTCs, which could provide reliable biological information originated from tumor. However, some issues need to be addressed before the utility of CTC-specific miRNAs in clinical setting. Taken together, we believe that CTC-specific miRNA detection will be trend for early breast cancer screening, diagnosis and treatment monitor in near future.


Subject(s)
Breast Neoplasms , MicroRNAs , Neoplastic Cells, Circulating , Humans , Female , Breast Neoplasms/diagnosis , Breast Neoplasms/genetics , Neoplastic Cells, Circulating/pathology , MicroRNAs/genetics , Clinical Relevance , Disease-Free Survival
4.
Appl Opt ; 61(23): 6861-6870, 2022 Aug 10.
Article in English | MEDLINE | ID: mdl-36255766

ABSTRACT

To address the problem of phase unwrapping for interferograms, a deep learning (DL) phase-unwrapping method based on adaptive noise evaluation is proposed to retrieve the unwrapped phase from the wrapped phase. First, this method uses a UNet3+ as the skeleton and combines with a residual neural network to build a network model suitable for unwrapping wrapped fringe patterns. Second, an adaptive noise level evaluation system for interferograms is designed to estimate the noise level of the interferograms by integrating phase quality maps and phase residues of the interferograms. Then, multiple training datasets with different noise levels are used to train the DL network to achieve the trained networks suitable for unwrapping interferograms with different noise levels. Finally, the interferograms are unwrapped by the trained networks with the same noise levels as the interferograms to be unwrapped. The results with simulated and experimental interferograms demonstrate that the proposed networks can obtain the popular unwrapped phase from the wrapped phase with different noise levels and show good robustness in the experiments of phase unwrapping for different types of fringe patterns.


Subject(s)
Algorithms , Deep Learning
5.
Molecules ; 27(20)2022 Oct 19.
Article in English | MEDLINE | ID: mdl-36296646

ABSTRACT

There is a wide variety of kinds of lipids, and complex structures which determine the diversity and complexity of their functions. With the basic characteristic of water insolubility, lipid molecules are independent of the genetic information composed by genes to proteins, which determine the particularity of lipids in the human body, with water as the basic environment and genes to proteins as the genetic system. In this review, we have summarized the current landscape on hormone regulation of lipid metabolism. After the well-studied PI3K-AKT pathway, insulin affects fat synthesis by controlling the activity and production of various transcription factors. New mechanisms of thyroid hormone regulation are discussed, receptor α and ß may mediate different procedures, the effect of thyroid hormone on mitochondria provides a new insight for hormones regulating lipid metabolism. Physiological concentration of adrenaline induces the expression of extrapituitary prolactin in adipose tissue macrophages, which promotes fat weight loss. Manipulation of hormonal action has the potential to offer a new therapeutic horizon for the global burden of obesity and its associated complications such as morbidity and mortality.


Subject(s)
Lipid Metabolism , Prolactin , Humans , Lipid Metabolism/physiology , Prolactin/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Hormones/metabolism , Adipose Tissue/metabolism , Insulin/metabolism , Thyroid Hormones/metabolism , Epinephrine , Lipids , Transcription Factors/metabolism , Water/metabolism
6.
Front Oncol ; 12: 903800, 2022.
Article in English | MEDLINE | ID: mdl-35924148

ABSTRACT

Breast cancer is one of the leading causes of mortality in females. Over the past decades, intensive efforts have been made to uncover the pathogenesis of breast cancer. Interleukin-6 (IL-6) is a pleiotropic factor which has a vital role in host defense immunity and acute stress. Moreover, a wide range of studies have identified the physiological and pathological roles of IL-6 in inflammation, immune and cancer. Recently, several IL-6 signaling pathway-targeted monoclonal antibodies have been developed for cancer and immune therapy. Combination of IL-6 inhibitory antibody with other pathways blockage drugs have demonstrated promising outcome in both preclinical and clinical trials. This review focuses on emerging studies on the strong linkages of IL-6/IL-6R mediated regulation of inflammation and immunity in cancer, especially in breast cancer.

7.
Sensors (Basel) ; 23(1)2022 Dec 20.
Article in English | MEDLINE | ID: mdl-36616631

ABSTRACT

In this paper, the problem of actuator and sensor faults of a quadrotor unmanned aerial vehicle (QUAV) system is studied. In the system fault model, time delay, nonlinear term, and disturbances of QUAV during the flight are considered. A fault estimation algorithm based on an intermediate observer is proposed. To deal with a single actuator fault, an intermediate variable is introduced, and the intermediate observer is designed for the system to estimate fault. For simultaneous actuator and sensor faults, the system is first augmented, and then two intermediate variables are introduced, and an intermediate observer is designed for the augmented system to estimate the system state, faults, and disturbances. The Lyapunov-Krasovskii functional is used to prove that the estimation error system is uniformly eventually bounded. The simulation results verify the feasibility and effectiveness of the proposed fault estimation method.

8.
Appl Opt ; 60(22): 6648-6658, 2021 Aug 01.
Article in English | MEDLINE | ID: mdl-34612908

ABSTRACT

A robust phase unwrapping algorithm based on a rank information filter is proposed to retrieve the unambiguous unwrapped phase from noisy wrapped phase images. First, a recursive phase unwrapping program, based on a rank information filter, is proposed to transform the problem of phase unwrapping for wrapped phase into the problem of the state estimation for state variables under the framework of a rank information filter, where a local phase gradient estimator based on the amended matrix pencil model (AMPM) is used to obtain phase gradient information required by the recursive phase unwrapping program. Second, an efficient path-following strategy based on heap-sort is used to guide the phase unwrapping path, which ensures that the recursive phase unwrapping program based on a rank information filter unwraps wrapped phase images along the path from high-quality pixels to low-quality pixels. Finally, the results obtained from synthetic data and experimental measured data demonstrate the effectiveness of the proposed method and show this method can obtain robust solutions from noisy wrapped phase images.

9.
Sci Prog ; 104(3): 368504211028395, 2021.
Article in English | MEDLINE | ID: mdl-34510991

ABSTRACT

Breast cancer is one the most common malignancies and leading cause of cancer-related mortality in women. Recent studies suggested that hypercholesterolemia may be the potential modifiable risk factors for breast cancer. Cholesterol was well-known for its strong association with cardiovascular disease for long. Moreover, solid evidence has been provided by different studies to illustrate the correlation between lipid and incidence in multiple cancers. Although the conclusion remains controversial or sometimes contrary, which may be due to the multifactorial nature of the disease and the disparity of ethnic population, it is critical to elucidate the relationship between specific cholesterol components in certain population and the exact underlying mechanism of the lipid-associated signaling pathway in breast cancer. The implications of dysregulated lipoproteins as therapeutic targets or options for breast cancer provide novel strategies for us in combating with this malignant disease, which may be achieved by manipulating lipid levels with pharmacological compounds.


Subject(s)
Breast Neoplasms , Cardiovascular Diseases , Hypercholesterolemia , Breast Neoplasms/drug therapy , Cardiovascular Diseases/epidemiology , Cholesterol/metabolism , Cholesterol/therapeutic use , Female , Humans , Hypercholesterolemia/drug therapy , Hypercholesterolemia/metabolism , Risk Factors
10.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 35(9): 828-831, 2019 Sep.
Article in Chinese | MEDLINE | ID: mdl-31750826

ABSTRACT

Objective To investigate the correlations between the expression of vascular endothelial growth factor (VEGF) and thrombospondin 1 (TSP-1) in breast cancer and the prognosis. Methods Immunohistochemical staining was used to detect the expression of VEGF and TSP-1 in 160 cases of breast cancer tissues and adjacent tissues, and the relationships between them were analyzed. Results The expression of TSP-1 significantly decreased and the expression of VEGF significantly increased in breast cancer tissues. Low expression of TSP-1 and high expression of VEGF were significantly associated with high clinical stage, poor differentiation, and lymph node metastasis. After 3 years of follow-up, the recurrence rate was 15.6%. Spearman rank correlation analysis showed that there was a positive correlation between the prognosis recurrence rate and the positive expression rate of VEGF (r=0.459), but negatively correlated with the positive expression rate of TSP-1 (r=-0.543). Logistic regression analysis showed that TSP-1 positive expression rate, VEGF positive expression rate, lymph node metastasis and clinical stage were the main independent risk factors for prognosis and recurrence. Conclusion The high expression of VEGF and the low expression of TSP-1 in breast cancer tissues are significantly correlated with the main clinical features. The recurrence rate of patients with high expression of VEGF and low expression of TSP is high.


Subject(s)
Breast Neoplasms/diagnosis , Thrombospondin 1/metabolism , Vascular Endothelial Growth Factor A/metabolism , Breast Neoplasms/metabolism , Female , Humans , Neoplasm Recurrence, Local , Prognosis
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