A new robust proportional-integrative-derivative (PID) tuning method based on nonlinear optimization is developed. The closed-loop bandwidth is maximized for specified gain and phase margins (GPM) ...with constraint on overshoot ratio, so that criteria of closed-loop performance and robustness are both satisfied. The equations of open-loop amplitude ratio and phase change are derived based on frequency analysis for the first-order plus time delay system with a PID controller in parallel form. The equation of closed-loop amplitude ratio is also explicitly given. The formulated optimization problem from the tuning method based on GPM with constraint on closed-loop amplitude ratio is further given. The method is demonstrated in simulation examples and compared with previous work on this topic.
Overwhelming evidence demonstrates that exosomes, a series of biologically functional small vesicles of endocytic origin carrying a variety of active constituents, especially tumor‐derived exosomes, ...contribute to tumor progression and metastasis. This review focuses on the specific multifaceted roles of exosomes in affecting sequenced four crucial processes of metastasis, through which cancer cells spread from primary to secondary organs and finally form macroscopic metastatic lesions. First, exosomes modulate the primary tumor sites to assist cancer growth and dissemination. In this part, five main biological events are reviewed, including the transfer of oncogenic constituents, the recruitment and activation of fibroblasts, the induction of angiogenesis, immunosuppression and epithelial‐mesenchymal transition (EMT) promotion. In Step 2, we list two recently disclosed mechanisms during the organ‐specific homing process: the exosomal integrin model and exosomal epidermal growth factor receptor (EGFR)/miR‐26/hepatocyte growth factor (HGF) model. Subsequently, Step 3 focuses on the interactions between exosomes and pre‐metastatic niche, in which we highlight the specific functions of exosomes in angiogenesis, lymphangiogenesis, immune modulation and metabolic, epigenetic and stromal reprogramming of pre‐metastatic niche. Finally, we summarize the mechanisms of exosomes in helping the metastatic circulating tumor cells escape from immunologic surveillance, survive in the blood circulation and proliferate in host organs.
The efficiency of supersonic combustion is largely dependent on inlet and injection parameters. Additional energy input is required in some off-design conditions, and nanosecond discharge actuation ...can be a solution. In the present study, a phenomenological model of a nanosecond-pulsed surface dielectric barrier discharge (NS-SDBD) actuator was developed to analyze the combustion enhancement effect for a supersonic combustor with transverse H2 injection. A seven-reaction H2–air combustion model was adopted for the numerical simulation. Dynamic mode decomposition (DMD) was employed to acquire temperature perturbation in spatial and temporal domains. The results show that the actuator provides additional temperature-increment and species transportation through compression waves. The combustion enhancement effect is mainly attributed to the flow perturbation in the shear layer, which promotes the turbulent diffusion of fuel. Given the same power input, the combustion efficiency at the shockwave reflection point is increased by 17.5%, and the flame height is increased by 15.4% at its maximum.
Simultaneous magnetic actuation and localization (SMAL) is a promising technology for accelerating and positioning the capsule in the human intestine for wireless capsule endoscopy (WCE). In this ...article, we propose a novel system that uses a rotating magnetic actuator and an external sensor array to achieve closed-loop SMAL for a capsule with two embedded magnetic rings. First, the state of the capsule is detected as "Stuck," "Synchronous," or "Missing" by studying the relationship between the theoretical actuating magnetic field and the measured total magnetic field. Then, the undesired interference with the localization system caused by the actuator is eliminated with an integral filter-based approach. Different models are proposed to solve the pose of the capsule according to the different states of the capsule, and the localization result is used to update the pose of the actuator to close the loop. Extensive experiments on phantoms and animal organs with different environmental conditions are carried out to validate the proposed framework. The state detection accuracy achieves 96.7%, and the capsule can be located with an accuracy of 5.5 mm and 5.2° in position and orientation, respectively. Experimental results show the feasibility of our proposed system and demonstrate the robustness, accuracy, actuation efficiency, and closed-loop performance of the system. Note to Practitioners -The motivation of this article is to solve the problem of controlling the movement of a wireless capsule endoscope in the human intestine to assist intestinal diagnosis and treatment. We present a feasible system design and corresponding algorithms to achieve closed-loop simultaneous actuation and localization of a robotic capsule. The design of a simple structure placed inside the capsule (i.e., two magnetic rings) and an external sensor array mounted on the examination bed can reduce the size and power consumption of the capsule, and the use of a rotating actuator helps improve the actuation efficiency. The proposed SMAL framework, which is composed of state detection, interference removal, multimodel localization, and actuator updating, can close the actuation-localization loop and improve the accuracy and robustness of the system. We demonstrate the superiority of the proposed framework compared with others through extensive experiments. In the future, our SMAL system can be combined with image- or ultrasound-based automatic diagnosis and is expected to provide doctors with better tools for digestive examinations.
To explore the effect of double-stranded RNA-dependent kinase (PKR) in acute lung injury (ALI) and resultant acute respiratory distress syndrome (ARDS). A mouse model of lipopolysaccharide ...(LPS)-induced ALI was used to evaluate the levels of phosphorylated (p)-PKR and NLRP3 in lung tissue, and the protective effects of a PKR inhibitor on lung injury. And in vitro, macrophages were incubated with LPS, with or without PKR inhibitor pre-treatment. It was observed that the levels of p-PKR protein and NLRP3 protein were significantly increased compared with those in control tissues after LPS administration. Meanwhile, treatment with PKR inhibitor decreased inflammation, injury score, wet/dry weight ratio, bronchoalveolar lavage fluid (BALF) protein levels, neutrophil count in BALF, myeloperoxidase activity and expression of high-mobility group box1(HMGB1) and interleukin(IL)-1β in the lungs of LPS-challenged mice. In vitro, we demonstrated that the levels of p-PKR and NLRP3, and cell mortality rate were increased in macrophages which were incubated with LPS compared with those without LPS administration, and PKR inhibitor significantly suppressed the level of NLRP3, caspase-1, HMGB1 and IL-1β. These results indicate that PKR plays a key role in ALI through NLRP3-pyrotosis pathway and pharmacological inhibition of PKR may have potential therapeutic effects in the treatment of patients with ALI and ARDS.
•The role of PKR in the pathogenesis of ALI/ARDS was explored.•Inhibition of PKR protects against LPS-induced ALI by suppressing NLRP3-pyrotosis pathway.•Pharmacological inhibition of PKR may have potential therapeutic effects in the treatment of patients with ALI and ARDS.
The spatiotemporal variations in suspended sediment concentration (SSC) in the lower reaches of the Yellow River exhibit significant variability and are influenced by reservoir operations. ...Understanding the spatiotemporal distribution characteristics of SSC in water holds crucial implications for environmental protection and reservoir operation management. Based on daily-scale SSC monitoring data from four hydrological stations in the lower Yellow River, this study established an SSC remote sensing model applicable to Landsat series satellite data. The independent variable of the model, Rrs(NIR)/(Rrs(G) + Rrs(R) + Rrs(SWIR)), demonstrated sensitivity to water bodies with different SSC values. Distinctive spatiotemporal characteristics in sediment transport were observed across the lower Yellow River. Spatially, the SSC values in the Sanmenxia and Xiaolangdi reservoirs were notably lower than those in other river sections, averaging 1008.42 ± 602.83 mg/L and 1177.89 ± 627.95 mg/L, respectively. Over time, the majority of the river sections (96%) exhibited decreasing trends in SSC during 1984–2022, particularly in the downstream Xiaolangdi reservoir, with average SSC values of 4265.58 ± 1101.77 mg/L in the 1980s and 1840.80 ± 2255.15 mg/L in the 2020s. Seasonal variations in SSC were prominent, with higher summer concentrations, averaging 5536.43 ± 2188.77 mg/L (2020s summer) and 814.11 ± 158.27 mg/L (2020s winter). Reductions in SSC during 1984–2022 primarily occurred in summer, weakening its seasonal variability in the lower Yellow River. Water discharge emerged as a critical factor influencing suspended sediment transport, with SSC increasing in high-water-flow months. Following the construction of the Xiaolangdi reservoir, the relationship between SSC and water discharge at different stations underwent notable alterations. This study enhances our understanding of the spatiotemporal dynamics of suspended sediment transport in the lower Yellow River, providing valuable insights for utilizing long-term Landsat series data in the dynamic monitoring of river sediment transport.
DNA methylation is a highly conserved epigenetic modification involved in many biological processes, including growth and development, stress response, and secondary metabolism. DNA demethylase ...(DNA-deMTase) genes have been identified in some plant species; however, there are no reports on the identification and analysis of DNA-deMTase genes in Foxtail millet (
L.). In this study, seven DNA-deMTases were identified in
. These DNA-deMTase genes were divided into four subfamilies (
,
,
, and
) by phylogenetic and gene structure analysis. Further analysis shows that the physical and chemical properties of these DNA-deMTases proteins are similar, contain the typical conserved domains of ENCO3c and are located in the nucleus. Furthermore, multiple cis-acting elements were observed in DNA-deMTases, including light responsiveness, phytohormone responsiveness, stress responsiveness, and elements related to plant growth and development. The DNA-deMTase genes are expressed in all tissues detected with certain tissue specificity. Then, we investigated the abundance of DNA-deMTase transcripts under abiotic stresses (cold, drought, salt, ABA, and MeJA). The results showed that different genes of DNA-deMTases were involved in the regulation of different abiotic stresses. In total, our findings will provide a basis for the roles of DNA-deMTase in response to abiotic stress.
Resveratrol is a natural polyphenolic compound that prevents inflammation in chondrocytes and animal models of osteoarthritis (OA) via yet to be defined mechanisms. The purpose of this study was to ...determine whether the protective effect of resveratrol on IL-1β-induced human articular chondrocytes was associated with the TLR4/MyD88/NF-кB signaling pathway by incubating human articular chondrocytes (harvested from osteoarthritis patients) with IL-1β before treatment with resveratrol. Cell viability was evaluated using the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay and TNFα levels in culture supernatants were measured by ELISA(Enzymelinked immunosorbent assay). The levels of TLR4 and its downstream signaling targets (MyD88 and TRAF6) and IL-1β were assessed by measuring the levels of mRNA and protein expression by real-time RT-PCR and western blot analysis, respectively, in addition to assessing NF-кB activation. In addition, TLR4 siRNA was used to block TLR4 expression in chondrocytes further demonstrating that resveratrol prevented IL-1β-mediated inflammation by TLR4 inhibition. We found that resveratrol prevented IL-1β-induced reduction in cell viability. Stimulation of chondrocytes with IL-1β caused a significant up-regulation of TLR4 and its downstream targets MyD88 and TRAF6 resulting in NF-кB activation associated with the synthesis of IL-1β and TNFα. These IL-1β-induced inflammatory responses were all effectively reversed by resveratrol. Furthermore, activation of NF-кB in chondrocytes treated with TLR4 siRNA was significantly attenuated, but not abolished, and exposure to resveratrol further reduced NF-кB translocation. These data suggested that resveratrol prevented IL-1β-induced inflammation in human articular chondrocytes at least in part by inhibiting the TLR4/MyD88/NF-кB signaling pathway suggesting that resveratrol has the potential to be used as a nutritional supplement to counteract OA symptoms.
Massive hemoptysis during pregnancy is very rare. Dieulafoy's disease is one of the causes of massive hemoptysis. There are few reports of ECMO use to treat massive hemoptysis during pregnancy.
We ...report for the first time a patient with Dieulafoy's disease diagnosed at 29 weeks of pregnancy. The patient's hemoptysis occurred rapidly with large volumes. The bleeding amount reached 500 ml within half an hour, with the development of asphyxia and respiratory and cardiac arrest due to a blood clot blocking the airway. After successful cardiopulmonary resuscitation, the ventilator could not maintain effective ventilation. Emergency establishment of VV-ECMO was performed to maintain oxygen, and hemostasis was successfully achieved by performing bronchial artery embolization twice. We successfully cleaned blood clots in the airway four times by freezing and using a foreign body retrieval basket with an electronic bronchoscope. At the same time, small and smooth nodular lesions were found under bronchoscopy, and blood vessels with a diameter of 1.5 mm were found under Doppler mode with an ultrasonic bronchoscope, which was consistent with a diagnosis of Dieulafoy's disease. VV-ECMO was successfully stopped on the 3rd day of the disease course, tracheal intubation was successfully removed on the 5th day of the disease course, and the patient was discharged with no complications on the 16th day of the disease course.
The effects of resveratrol on osteoarthritis (OA) pathogenesis have been demonstrated in vitro and in animal models employing intra-articular injections. However, the potential for oral resveratrol ...supplements to mediate protective effects on OA have not been examined. Therefore, the aim of the present study was to investigate the potential anti-OA effects of oral resveratrol on mice fed a high-fat diet (HFD). C57BL/6J male mice were fed either a standard diet or a HFD, and a subset of the latter also received varying doses of resveratrol. Twelve weeks later, all of the animals were sacrificed and knee joints were evaluated with histological, immunohistochemical, and TUNEL analyses. Mice that received a HFD had significantly greater body weights than the control mice and also exhibited features consistent with knee OA. The mice that received a HFD in combination with low, intermediate, or high doses of resveratrol were only slightly heavier than the control mice at the end of 12 weeks. Quantitative histological assessments indicated that resveratrol treatment partly recovered joint structure in the mice that received a HFD, while high doses of resveratrol prevented the degradation of type II collagen into C-telopeptide of type II collagen (CTX-II) and retained type II collagen expression in cartilage. Furthermore, TUNEL analyses revealed a reduction in chondrocyte apoptosis in the resveratrol-treated mice compared with the HFD mice. Thus, oral resveratrol appears to exert anti-OA effects in a mouse model of HFD-induced OA, thereby highlighting the potential preventive and therapeutic value of administering resveratrol for obesity-associated OA.
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