42 research outputs found
Roles of plant growth substance in callus induction of Achyranthes bidentata
   In this research, callus from leaves, petioles and stems of Achyranthes bidentata was evidently initiated by plant growth substance, in which 2,4-dichlorophenoxyacetic acid (2,4-D) was very important to callus induction, but effects of other plant growth substances were various, and the optimum combination of plant growth substances for callus induction from leaves, petioles and stems was respectively obtained. Compared with callus induction from leaves and petioles, callus induction from stems was easier, and the higher induction rate and bigger mass of callus from stems were obtained. This study showed that the dedifferentiation capacity of various explants from Achyranthes bidentata was obviously different, and effects of plant growth substance on callus induction from various explants of Achyranthes bidentata were significantly diverse
Templated assembly of micropatterned Au-Ni nanoparticles on laser interference-structured surfaces by thermal dewetting
This paper introduces a laser-interference-controlled electrochemical deposition method for direct fabrication of periodically micropatterned magnetite (Fe3O4) nanoparticles (NPs). In this work, Fe3O4Â NPs were controllably synthesized on the areas where the photoconductive electrode was exposed to the periodically patterned interferometric laser irradiation during the electrodeposition. Thus, the micropattern of Fe3O4Â NPs was controlled by interferometric laser pattern, and the crystallization of the particles was controlled by laser interference intensity and electrochemical deposition conditions. The bottom-up electro- chemical approach was combined with a top-down laser interference method- ology. This maskless method allows for in situ fabrication of periodically patterned magnetite NPs on the microscale by electrodeposition under room temperature and atmospheric pressure conditions. In the experiment, Fe3O4Â NPs with the mean grain size below 100 nm in the pattern of 5-lm line array were achieved within the deposition time of 100 s. The experiment results have shown that the proposed method is a one-step approach in fabricating large areas of periodically micropatterned magnetite NPs.
Learnable Visual Words for Interpretable Image Recognition
To interpret deep models' predictions, attention-based visual cues are widely
used in addressing \textit{why} deep models make such predictions. Beyond that,
the current research community becomes more interested in reasoning
\textit{how} deep models make predictions, where some prototype-based methods
employ interpretable representations with their corresponding visual cues to
reveal the black-box mechanism of deep model behaviors. However, these
pioneering attempts only either learn the category-specific prototypes and
deteriorate their generalizing capacities, or demonstrate several illustrative
examples without a quantitative evaluation of visual-based interpretability
with further limitations on their practical usages. In this paper, we revisit
the concept of visual words and propose the Learnable Visual Words (LVW) to
interpret the model prediction behaviors with two novel modules: semantic
visual words learning and dual fidelity preservation. The semantic visual words
learning relaxes the category-specific constraint, enabling the general visual
words shared across different categories. Beyond employing the visual words for
prediction to align visual words with the base model, our dual fidelity
preservation also includes the attention guided semantic alignment that
encourages the learned visual words to focus on the same conceptual regions for
prediction. Experiments on six visual benchmarks demonstrate the superior
effectiveness of our proposed LVW in both accuracy and model interpretation
over the state-of-the-art methods. Moreover, we elaborate on various in-depth
analyses to further explore the learned visual words and the generalizability
of our method for unseen categories
Active Disturbance Rejection Control of Valve-Controlled Cylinder Servo Systems Based on MATLAB-AMESim Cosimulation
The valve-controlled cylinder position servo system has the advantages of large output force and large power. As characteristics of nonlinearity and uncertainty exist in the hydraulic servo system, it is difficult for the traditional PID control to meet the requirements of high precision and control. The active disturbance rejection control (ADRC) considers the uncertainty of the system and external disturbances as the total disturbance. In this paper, the valve-controlled cylinder servo system is designed based on ADRC, its working principle is described, and its mathematical model and cosimulation model based on MATLAB-AMESim are established. In the case of constant load, variable load, and long pipeline, the comparative simulation of ADRC and PID is carried out. The simulation results show that the ADRC can effectively suppress the disturbance of the internal parameter changes and external load changes of the hydraulic system and has strong robustness and high control accuracy. This study provides a reference for the application of ADRC in electrohydraulic servo systems
Adiponectin protects rat myocardium against chronic intermittent hypoxia-induced injury via inhibition of endoplasmic reticulum stress.
Obstructive sleep apnea syndrome (OSAS) is associated with many cardiovascular disorders such as heart failure, hypertension, atherosclerosis, and arrhythmia and so on. Of the many associated factors, chronic intermittent hypoxia (CIH) in particular is the primary player in OSAS. To assess the effects of CIH on cardiac function secondary to OSAS, we established a model to study the effects of CIH on Wistar rats. Specifically, we examined the possible underlying cellular mechanisms of hypoxic tissue damage and the possible protective role of adiponectin against hypoxic insults. In the first treatment group, rats were exposed to CIH conditions (nadir O2, 5-6%) for 8 hours/day, for 5 weeks. Subsequent CIH-induced cardiac dysfunction was measured by echocardiograph. Compared with the normal control (NC) group, rats in the CIH-exposed group experienced elevated levels of left ventricular end-systolic dimension and left ventricular end-systolic volume and depressed levels of left ventricular ejection fraction and left ventricular fractional shortening (p<0.05). However, when adiponectin (Ad) was added in CIH + Ad group, we saw a rescue in the elevations of the aforementioned left ventricular function (p<0.05). To assess critical cardiac injury, we detected myocardial apoptosis by Terminal deoxynucleotidyl transfer-mediated dUTP nick end-labeling (TUNEL) analysis. It was showed that the apoptosis percentage in CIH group (2.948%) was significantly higher than that in NC group (0.4167%) and CIH + Ad group (1.219%) (p<0.05). Protein expressions of cleaved caspase-3, cleaved caspase-9, and cleaved-caspase-12 validated our TUNEL results (p<0.05). Mechanistically, our results demonstrated that the proteins expressed with endoplasmic reticulum stress and the expression of reactive oxygen species (ROS) were significantly elevated under CIH conditions, whereas Ad supplementation partially decreased them. Overall, our results suggested that Ad augmentation could improve CIH-induced left ventricular dysfunction and associated myocardial apoptosis by inhibition of ROS-dependent ER stress
Head-to-Head Comparison of Different Blood Collecting Tubes for Quantification of Alzheimer’s Disease Biomarkers in Plasma
To examine whether the type of blood collection tubes affects the quantification of plasma biomarkers for Alzheimer’s disease analyzed with a single-molecule array (Simoa), we recruited a healthy cohort (n = 34, 11 males, mean age = 28.7 ± 7.55) and collected plasma in the following tubes: dipotassium ethylenediaminetetraacetic acid (K2-EDTA), heparin lithium (Li-Hep), and heparin sodium (Na-Hep). Plasma tau, phosphorylated tau 181 (p-tau181), amyloid β (1–40) (Aβ40), and amyloid β (1–42) (Aβ42) were quantified using Simoa. We compared the value of plasma analytes, as well as the effects of sex on the measurements. We found that plasma collected in Li-Hep and Na-Hep tubes yielded significantly higher tau and p-tau181 levels compared to plasma collected in K2-EDTA tubes from the same person, but there was no difference in the measured values of the Aβ40, Aβ42, and Aβ42/40 ratio. Therefore, the type of blood collecting tubes should be considered when planning studies that measure plasma tau
Globular Adiponectin Attenuated H2O2-Induced Apoptosis in Rat Chondrocytes by Inducing Autophagy Through the AMPK/ mTOR Pathway
Background/Aims: Chondrocyte apoptosis is closely related to the development and progression of osteoarthritis. Global adiponectin (gAPN), secreted from adipose tissue, possesses potent anti-inflammatory and antiapoptotic properties in various cell types. This study aimed to investigate the role of autophagy induced by gAPN in the suppression of H2O2-induced apoptosis and the potential mechanism of gAPN-induced autophagy in chondrocytes. Methods: H2O2 was used to induce apoptotic injury in rat chondrocytes. CCK-8 assay was performed to determine the viability of cells treated with different concentrations of gAPN with or without H2O2. Cell apoptosis was detected by flow cytometry and TUNEL staining. Mitochondrial membrane potential was examined using JC-1 fluorescence staining assay. The autophagy inhibitors 3-MA and Bafilomycin A1 were used to treat cells and then evaluate the effect of gAPN-induced autophagy. To determine the downstream pathway, chondrocytes were preincubated with the AMPK inhibitor Compound C. Beclin-1, LC3B, P62 and apoptosis-related proteins were identified by Western blot analysis. Results: H2O2 (400 µM)-induced chondrocytes apoptosis and caspase-3 activation were attenuated by gAPN (0.5 µg/mL). gAPN increased Bcl-2 expression and decreased Bax expression. The loss of mitochondrial membrane potential induced by H2O2 was also abolished by gAPN. Furthermore, the antiapoptotic effect of gAPN was related to gAPN-induced autophagy by increased formation of Beclin-1 and LC3B and P62 degradation. In particular, the inhibition of gAPN-induced autophagy by 3-MA prevented the protective effect of gAPN on apoptosis induced by H2O2. Moreover, gAPN increased p-AMPK expression and decreased p-mTOR expression. Compound C partly suppressed the expression of autophagy-related proteins and restored the expression of p-mTOR suppressed by gAPN. Thus, the AMPK/mTOR pathway played an important role in the induction of autophagy and protection of H2O2-induced chondrocytes apoptosis by gAPN. Conclusions: gAPN protected chondrocytes from H2O2-induced apoptosis by inducing autophagy possibly associated with AMPK/mTOR signal-pathway activation