In this paper, an adaptive fuzzy output feedback control approach is proposed for single-input-single-output nonlinear systems without the measurements of the states. The nonlinear systems addressed ...in this paper are assumed to possess unmodeled dynamics in the presence of unstructured uncertainties and dynamic disturbances, where the unstructured uncertainties are not linearly parameterized, and no prior knowledge of their bounds are available. Fuzzy logic systems are used to approximate the unstructured uncertainties, and a state observer is developed to estimate the unmeasured states. By combining the backstepping technique with the small-gain approach, a stable adaptive fuzzy output feedback control method is proposed. It is shown that by applying the proposed adaptive fuzzy control approach, the closed-loop systems are semiglobally uniformly ultimately bounded. The effectiveness of the proposed approach is illustrated from simulation results.
It is generally supposed that a transition from the normal decay phase (decay slope ∼−1) to a steeper phase (decay slope ∼−2) could be suggested as a jet break. The jet opening angle θjet is then ...calculated from the jet break time of the afterglow light curve. This allows the derivation of the collimation-corrected energy Ejet of those gamma-ray bursts (GRBs). We extensively searched for the GRBs with jet break features from multiwavelength afterglow light curves, and 138 GRBs with significant breaks were collected. The jet break times of those GRBs mainly range from 1000 to 106 s, and the distribution of the collimation-corrected energy Ejet peaks at ∼1050 erg. We also confirmed the Eγ,iso−Ep,i, Ejet−Ep,i and Eγ,iso−θjet relations, and found Eγ,iso−Tj,z−Ep,i relation remains tight with more multiwavelength data. This tight Eγ,iso−Tj,z−Ep,i relation is also conformed by different groups of our selected GRBs in the paper. In addition, another two new and tighter correlations among Ejet−Tj,z−Ep,i are well confirmed for different circumburst mediums in this paper. We suggest that those tight three-parameter correlations are more physical, and could be widely applied to constrain the cosmological parameters.
Background
Gastric epithelial barrier disruption constitutes a crucial step in gastric cancer (GC). We investigated these disruptions during the Correa's cascade timeline to correlate epithelial ...barrier dysfunction.
Materials and Methods
This study was conducted as a single‐center, non‐randomized clinical trial in China from May 2019 to October 2022. Patients with chronic atrophic gastritis (CAG), gastric intestinal metaplasia (GIM), low‐grade intraepithelial neoplasia (LGIN), high‐grade intraepithelial neoplasia (HGIN), and intramucosal carcinoma underwent probe‐based confocal laser endomicroscopy (pCLE). The pCLE scoring system was used to assess gastric epithelial barrier disruption semi‐quantitatively.
Results
We enrolled 95 patients who underwent a pCLE examination. The control group consisted of 15 individuals, and the experimental group included 17 patients with CAG, 27 patients with GIM, 20 patients with LGIN, and 16 patients with early gastric cancer (EGC). Apart from CAG, which showed no significant difference compared to the control group, a significantly higher incidence of gastric epithelial barrier damage was found in the GIM, LGIN, and EGC groups compared to the control group (Kruskal–Wallis H test = 69.295, p < 0.001). There is no difference in LGIN patients between GIM and LGIN areas, and there is no difference between the two groups compared with the EGC group. The intestinal metaplasia area in LGIN patients causes more severe gastric epithelial damage compared to that in non‐LGIN patients. Additionally, compared to control group, a significant difference (p < 0.001) was noted between individuals with Helicobacter pylori‐positive atrophic gastritis and those with IM, whereas no significant difference (p > 0.05) was observed among individuals with H. pylori‐negative atrophic gastritis.
Conclusions
The gastric epithelial barrier remains dysfunctional from the initiation of H. pylori infection to GC progression. Beyond the “point of no return,” subsequent carcinogenesis processes may be attributed to other mechanisms.
In this article, the finite-time fault-tolerant control (FTC) problem is investigated for uncertain nonlinear nonstrict-feedback systems. The nonstrict-feedback nonlinear system considered in this ...article contains unmeasured states, unknown control directions, unknown nonlinear dynamics, and actuator faults (both lock-in-place and loss of effectiveness). To realize the control objective, fuzzy-logic systems are used to approximate the unknown nonlinear functions, and a high-gain fuzzy state observer is developed. By using the Nussbaum function technique and combining with the adaptive backstepping control design, a fuzzy adaptive finite-time output-feedback FTC scheme is proposed. It is proved that the closed-loop system is practical finite-time stable (PFTS), and the system output can track a given reference signal. Simulation and comparison results further show the effectiveness of the proposed control strategy.
Ovarian granulosa cells (GCs) proliferate and differentiate along with follicular growth, and this is indispensable for oocyte development and female fertility. Although the role of ...macroautophagy/autophagy in ovarian function has been reported, its contribution to the regulation of GC characteristics remains elusive. The siRNA-mediated knockdown of two key autophagy-related genes ATG5 and BECN1 and the autophagy inhibitor chloroquine were used to interfere with autophagy in GCs. Inhibition of autophagy both genetically and pharmacologically resulted in decreased expression of genes associated with GC differentiation, including CYP19A1/Aromatase and FSHR, as well as in reduced estradiol synthesis. Mechanistically, when autophagy was disrupted, the transcription factor WT1 accumulated in GCs due to its insufficient degradation by the autophagic pathway, and this inhibited GC differentiation. Finally, decreased expression of several autophagy-related genes, as well as reduced LC3-II:LC3-I and elevated SQSTM1/p62 protein levels, which are indications of decreased autophagy, were detected in GCs from biochemical premature ovarian insufficiency patients. In summary, our study reveals that autophagy regulates the differentiation of ovarian GCs by degrading WT1 and that insufficient autophagy might be involved in ovarian dysfunction.
Abbreviations: ATG: autophagy related; bPOI: biochemical premature ovarian insufficiency; CHX: cycloheximide; Co-IP: co-immunoprecipitation; CQ: chloroquine; E
2
: estradiol; FSH: follicle stimulating hormone; FSHR: follicle stimulating hormone receptor; GC: granulosa cell; LIR: LC3-interacting region; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; POI: premature ovarian insufficiency; RAP: rapamycin; siRNA: small interfering RNA; WT1: WT1 transcription factor
Supercritical carbon dioxide extraction (SC-CO
2) of oil from desilked silkworm pupae was performed. Response surface methodology (RSM) was applied to optimize the parameters of SC-CO
2 extraction. ...The effects of independent variables, including pressure, temperature, CO
2 flow rate, and extraction time, on the yield of oil were investigated. The statistical analysis showed that the pressure, extraction time, and the quadratics of pressure, extraction time, and CO
2 flow rate, as well as the interactions between pressure and temperature, and temperature and flow rate, showed significant effects on oil yield. The optimal extraction condition for oil yield within the experimental range of the variables researched was at 324.5
bar, 39.6
°C, 131.2
min, and 19.3
L/h. At this condition, the yield of oil was predicted to be 29.73%. The obtained silkworm pupal oil contained more than 68% total unsaturated fatty acids, and alpha-linolenic acid (ALA) accounted for 27.99% in the total oil.
The effect of different levels (0.5%, 1%, and 2%) of hydroxypropylmethylcellulose (HPMC) addition on the rheological, thermal, and physicochemical properties of wheat gluten as well as the transition ...of water status was investigated during frozen storage (0 d, 15 d, 30 d, and 60 d). Apart from the samples with 2% HPMC, a significant decrease in rheological parameters (G′, and G″) was observed with increasing time of frozen storage for all gluten samples. These results were in agreement with the determination of free sulfydryl content, which suggest that disulfide bonds of gluten were ruptured during frozen storage, and HPMC could inhibit the effect of frozen storage via restraining recrystallization. On the other hand, the analyses of differential scanning calorimetry (DSC) showed that as frozen storage time was prolonged, the content of freezable water (CFW) increased significantly for both samples with and without HPMC; however, in the same frozen storage time, CFW dropped progressively with the increase in the levels of HPMC addition. The results of Time-Domain NMR (TD-NMR) also revealed that HPMC could retard the transition of water status from the unfreezable to the freezable so as to lower the amount and size of ice crystals. In addition, the micrographs of scanning electron microscopy (SEM) further confirmed that more disordered and weaker microstructures in gluten without HPMC were induced by frozen storage. On the contrary, more integral and uniform microstructures of gluten with 2% HPMC were observed to demonstrate that HPMC could stabilize gluten network. These results in the present study indicated that HPMC could be used in the food industry as an effective cryoprotectant.
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•Addition with 2% HPMC stabilized the rheological parameters (G′ and G″) of gluten.•HPMC lowered water mobility and restricted an increase in freezable water in frozen gluten.•HPMC prevented the breakage of inter-/intra-chain -S-S- of gluten proteins.•HPMC protected the microstructure and conformation of gluten network.
In this paper, two adaptive neural network (NN) decentralized output feedback control approaches are proposed for a class of uncertain nonlinear large-scale systems with immeasurable states and ...unknown time delays. Using NNs to approximate the unknown nonlinear functions, an NN state observer is designed to estimate the immeasurable states. By combining the adaptive backstepping technique with decentralized control design principle, an adaptive NN decentralized output feedback control approach is developed. In order to overcome the problem of "explosion of complexity" inherent in the proposed control approach, the dynamic surface control (DSC) technique is introduced into the first adaptive NN decentralized control scheme, and a simplified adaptive NN decentralized output feedback DSC approach is developed. It is proved that the two proposed control approaches can guarantee that all the signals of the closed-loop system are semi-globally uniformly ultimately bounded, and the observer errors and the tracking errors converge to a small neighborhood of the origin. Simulation results are provided to show the effectiveness of the proposed approaches.
This study aimed to analyze the most influential publications on vertebral augmentation for treating osteoporotic vertebral compression fracture. The Web of Science database was searched using the ...key words "percutaneous vertebroplasty," "percutaneous kyphoplasty," "balloon kyphoplasty," "vertebroplasty," "kyphoplasty," and "vertebral augmentation." The top 100 publications were arranged by citations per year and descriptively and visually analyzed. The top 100 publications were cited 25,482 times, with an average of 14.4 citations per paper per year. The corresponding authors of the publications represented 17 nations, with most authors being American (46 authors). Thirty-two journals were involved, with SPINE issuing the most publications (24 papers of the 100). Clinical research (73 of the 100 papers) outnumbered basic studies (14 papers) and systematic reviews (13 papers), and the most publications were published between 2000 and 2004. Co-citation analysis of the key words indicated that the top 5 focus areas were "complication," "balloon kyphoplasty," "vertebral compression fracture," "biomechanics," and "calcium phosphate cement." The top 3 keywords with the strongest citation bursts were "compression fracture," "cement," and "balloon kyphoplasty." The keywords with persistent strong citation bursts are "balloon kyphoplasty" and "augmentation." There are still contrary opinions about vertebral augmentation; new research should be conducted with more deliberate design and longer follow-up.
► Hydrogen sulfide (H
2S) delayed flower opening and senescence in cut flowers and branches. ► Flowers that had senesced showed higher levels of malondialdehyde (MDA, an indicator of oxidative damage ...to cells) and lower amounts of endogenous H
2S. ► H
2S increased the activities of antioxidant enzymes and sustained much lower levels of H
2O
2 and O
2
− in cut flowers. ► H
2S is involved in improving longevity of cut flowers and functions in an antioxidant role in plants.
We report the effects of hydrogen sulfide (H
2S) on flower senescence in various species of cut flowers. H
2S was found to delay flower opening and senescence in cut flowers and branches from
Erigeron annuus (L.),
Euonymus maackii Rupr.,
Hibiscus syriacus L.,
Liriope spicata (Thump.),
Loropetalum chinense (R. Br.),
Punica granatum L.,
Rosa chinensis Jacq., and
Salix matsudana Koidz. Cut explants of these plants were cultured in solution containing different concentrations of the H
2S donor, NaHS. H
2S donor treatment prolonged the vase time of cut flowers and prevented senescence in a dose-dependent manner. We measured the levels of malondialdehyde (MDA) as an indicator of oxidative damage to cells and showed that it was inversely related to endogenous H
2S concentration in explants. Flowers that had senesced showed higher levels of MDA and lower amounts of H
2S. Furthermore, NaHS treatment increased the activities of catalase (CAT), superoxide dismutase (SOD), ascorbate peroxidase (APX) and guaiacol peroxidase (POD), and sustained much lower levels of H
2O
2 and O
2
− in cut flowers of
E.
annuus and explant leaves of
S.
matsudana. The present study implies that H
2S is involved in improving longevity of cut flowers and functions in activity of antioxidant enzymes in plants.
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