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Deep reinforcement learning has significantly advanced robot manipulations by providing an alternative solution for designing control strategies using raw images as direct inputs. While images offer additional environmental information, the end-to-end policy training manner (from image to action) requires simultaneous representation and task learning by the agent. This often necessitates a substantial number of interaction samples to achieve satisfactory policy performance. Previous works has attempted to address this challenge by learning a visual representation model that encodes the entire image into a low-dimensional vector before the policy training. However, since this vector contains both robot and object information, it inevitably introduces coupling within the state, which can mislead the policy training process. In this study, a novel method called Reinforcement Learning with Decoupled State Representation is proposed to effectively decouple robot and object information within the state representation. Experimental results demonstrate that the proposed method exhibits faster learning speed and achieves superior performance compared to previous methods across various robot manipulation tasks. Moreover, with only 3096 offline images, the proposed method successfully applies to real-world robot pushing tasks, which demonstrates its high practicability. [ABSTRACT FROM AUTHOR]

The environment and structure of the tanks used in aquaculture vessels are remarkably different from those of ordinary ships, and the resulting problem of structural strength is related to breeding safety. In this study, a model of aquaculture tank corrosion was constructed by using the multiphysical field coupling analysis software COMSOL Multiphysics, and wave and sloshing loads were calculated on the basis of potential flow theory and computational fluid dynamics. The influence of different calculation methods for corrosion allowance and sloshing load on the structural responses of aquaculture tanks was analyzed. Through our calculations, we found that the corrosion of aquaculture tanks is different from that of ordinary ships. The corrosion allowance in Rules for the Classification of Sea-going Steel Ships is small, and the influence of the aquaculture environment on corrosion can be ignored. Compared with the method set in the relevant rules, our proposed coupling direct calculation method for the structural response calculation of aquaculture tanks can better combine the specific environment of aquaculture tanks and provide more accurate calculations. [ABSTRACT FROM AUTHOR]

Ischemic heart failure (HF) remains a leading cause of morbidity and mortality. Maintaining homeostasis of cardiac function and preventing cardiac remodeling deterioration are critical to halting HF progression. Methyltransferase-like protein 13 (Mettl13) has been shown to regulate protein translation efficiency by acting as a protein lysine methyltransferase, but its role in cardiac pathology remains unexplored. This study aims to characterize the roles and mechanisms of Mettl13 in cardiac contractile function and HF. We found that Mettl13 was downregulated in the failing hearts of mice post-myocardial infarction (MI) and in a cellular model of oxidative stress. Cardiomyocyte-specific overexpression of Mettl13 mediated by AAV9-Mettl13 attenuated cardiac contractile dysfunction and fibrosis in response to MI, while silencing of Mettl13 impaired cardiac function in normal mice. Moreover, Mettl13 overexpression abrogated the reduction in cell shortening, Ca2+ transient amplitude and SERCA2a protein levels in the cardiomyocytes of adult mice with MI. Conversely, knockdown of Mettl13 impaired the contractility of cardiomyocytes, and decreased Ca2+ transient amplitude and SERCA2a protein expression in vivo and in vitro. Mechanistically, Mettl13 impaired the stability of c-Cbl by inducing lysine methylation of c-Cbl, which in turn inhibited ubiquitination-dependent degradation of SERCA2a. Furthermore, the inhibitory effects of knocking down Mettl13 on SERCA2a protein expression and Ca2+ transients were partially rescued by silencing c-Cbl in H2O2-treated cardiomyocytes. In conclusion, our study uncovers a novel mechanism that involves the Mettl13/c-Cbl/SERCA2a axis in regulating cardiac contractile function and remodeling, and identifies Mettl13 as a novel therapeutic target for ischemic HF. [ABSTRACT FROM AUTHOR]

A LiNiO2 cathode material was cosubstituted with Mg and Al to obtain LiNi0.90Mg0.05Al0.05O2 via solid-state sintering of a mixture containing stoichiometric amounts of Ni(OH)2 precursor, LiOH·H2O, MgO, and Al2O3. The number of Li/Ni anti-site defects shown by X-ray diffraction was significantly reduced after cosubstitution of Mg and Al, and a 2–3 nm spinel-like structure was directly observed on the surface of LiNi0.90Mg0.05Al0.05O2 by Cs-corrected scanning transmission electron microscopy. This cosubstitution-induced structural modification enhanced the stability of the material during cycling. The LiNi0.90Mg0.05Al0.05O2 half-cell showed an initial capacity of 210.8 mAh/g at 0.1 C (2.75–4.3 V) and excellent capacity retention of ~ 93.1% after 300 subsequent cycles at 1 C. In contrast, the bare LiNiO2 half-cell exhibited a capacity retention of only ~ 23.4% under the same cycling conditions, despite a high initial specific capacity of 238.1 mAh/g. Furthermore, the LiNi0.90Mg0.05Al0.05O2 half-cell also showed a much better rate performance than its bare LiNiO2 counterpart, with capacity retention levels at 5 C of 68.1% for the former and only 5.2% for the latter. [ABSTRACT FROM AUTHOR]

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The natural bacterial spores have inspired the development of artificial spores, through coating cells with protective materials, for durable whole-cell catalysis. Despite attractiveness, artificial spores developed to date are generally limited to a few microorganisms with their natural endogenous enzymes, and they have never been explored as a generic platform for widespread synthesis. Here, we report a general approach to designing artificial spores based on Escherichia coli cells with recombinant enzymes. The artificial spores are simply prepared by coating cells with polydopamine, which can withstand UV radiation, heating and organic solvents. Additionally, the protective coating enables living cells to stabilize aqueous-organic emulsions for efficient interfacial biocatalysis ranging from single reactions to multienzyme cascades. Furthermore, the interfacial system can be easily expanded to chemoenzymatic synthesis by combining artificial spores with metal catalysts. Therefore, this artificial-spore-based platform technology is envisioned to lay the foundation for next-generation cell factory engineering. Whole-cell biocatalysis is of interest for the efficient production of a range of products but cell stability can be an issue. Here, the authors turn recombinant enzyme-producing E. coli into artificial spores to add protection from UV radiation, heating, and organic solvents by coating the cells with polydopamine to create robust cell factories. [ABSTRACT FROM AUTHOR]

As the global ecosystem has been severely disturbed by an increasing number of human activities at different scales, remote sensing technology, as an effective quantitative measure of environmental quality, has been widely used. The remote sensing ecological index (RSEI) is one of the most popular and comprehensive ecological quality assessment indices based on the remote sensing data. However, the RSEI model exhibits that the ecological environment under natural conditions is not limited by the spatial scales. In addition, the model has major shortcomings in index selection and eigenvector, which greatly limit the application of RSEI. In this paper, the RSEI model is improved and a remote sensing ecological index optimized by the regional scale (RO-RSEI) is proposed. The result of the study, conducted in Shuangyang District, Changchun City, Jilin Province, shows that the RO-RSEI model has regional ecological significance after the introduction of the scale theory of landscape ecology; the index is preferred to solve problems like the RSEI model applied mechanization and baseless index selection. Meanwhile, due to the optimization of the eigenvector contribution of the optimal index, it solves the problems like non-unique model calculation result caused by principal component analysis or even antipodal calculation result. Compared with the RSEI model, the monitoring result of RO-RSEI model can better reflect the regional ecological changes. The improved model offers the possibility of monitoring ecological environment quality with remote sensing big data and provides a scientific basis for future scholars' batch computing. [ABSTRACT FROM AUTHOR]

Uni-portal video-assisted thoracoscopic approach is currently a popular surgical technique in general thoracic surgery. After operation, a chest tube is usually placed through the incision to drain the effusion and gas from the thoracic cavity. In the conventional method, the retaining stitches should be taken out ten days after removing chest drain. To get better would-healing and avoid unsightly scar, we explored a method of anchoring chest drain and two-layer suture for Uni-portal incision without removing stitches post operation. [ABSTRACT FROM AUTHOR]

Person attribute recognition, i.e., the prediction of a fixed set of semantic attributes given an image of a person, becomes an important topic in the field of computer vision. Recently, methods based on convolutional neural networks have shown outstanding performance in this area. They usually employ a CNN network to mine the shared feature representation followed by several layers for attribute classification. To improve the representation ability of the model, many methods element-add or concatenate coarse and fine feature maps to fuse information at different feature levels. However, these methods didn't fully exploit the interaction of multi-level convolutional feature maps for person attribute analysis and not consider the correlation of attributes for the same person. In this paper, we introduce a kind of correlation feature, which exploits the high order interaction of coarse and fine feature maps to capture the robust feature representation from multi-level convolution layers as the image representation for person attribute recognition. Moreover, we propose an intraperson attribute loss to explicitly model the correlation of attributes for the same person. We experiment our proposed model on CIFAR-10 dataset, Berkeley Human Attributes dataset, PA-100 K dataset, and experimental results show the better performance of the feature representation and the effectiveness of intra-person attribute loss. [ABSTRACT FROM AUTHOR]

Micro/nano positioning technologies have been attractive for decades in industrial and scientific applications fields. The actuators have inherent hysteresis that can cause system unexpected behave in some extend. In this research, the authors used extented unparallel Prandtl-Ishlinshii (EUPI) models to represent the input-output relationship of a piezo-driven micro position stage. Integral inverse (I-I) compensator is used for compensating the hysteresis characteristics of the micro positioning stage and compared with direct inverse (D-I) compensator and inverse model (I-M) compensator. However, the accuracy and the robustness of the I-I compensator are worse when there is noisy in the system, a novel sliding-mode-like-control with EUPI (SMLC-EUPI) method was proposed and analyzed by different trajectory tracking experiments in Matlab environment. Though the above strategies can alleviate most deviation, the adjustment of the SMLC's parameters is very complex. So the fuzzy method is used to adjust these parameters and be verified by trajectory tracking experiments. Finally, for validating the proposed control method, the paper did the corresponding experiment in microscope with CMOS and obtained convincing results. [ABSTRACT FROM AUTHOR]

Taking dodecanethiol as the representative, we investigated the corrosion inhibition performance of SAL in seawater under pressures from 0.1 to 9 MPa. By using scanning Kelvin probe, the dodecanethiol SAL is confirmed to build on Cu surface, and the modification of SAL has positively shifted the surface potential to realize the inertness. Electrochemical techniques, such as electrochemical impedance spectroscopy and potentiodynamic polarization were used to reveal the corrosion behavior of Cu modified by SAL under the different pressure, i e, 0.1, 3, 6, and 9 MPa. It is indicated that the longer modification time affords better corrosion resistance to Cu. Higher static pressure is easier to deteriorate the corrosion inhibition capability due to the penetration effect. A plausible mechanism is proposed to illustrate the degradation process of SAL in the high pressure seawater environment. [ABSTRACT FROM AUTHOR]

A series of Ag-modified porous ZnMgO nanorods (Ag/ZnMgO NRs) photocatalysts were prepared using a solvothermal method followed by a calcination treatment. The ZnMgO NRs showed a porous rod-like structure. Ag nanoparticles (NPs) were successfully loaded on the ZnMgO NRs to form a heterostructure. The rod-like structure of ZnMgO NRs was not affected after the modification with Ag NPs. The photocatalytic degradation performance under white light irradiation showed that 3% of Ag-modified porous ZnMgO NRs presented the highest photocatalytic performance, which can achieve the completely degradation of Rhodamine B and norfloxacin in only 20 min and 10 min, respectively. The improved photocatalytic performance of Ag/ZnMgO NRs is attributed to the key role of Ag NPs, which can effectively reduce the recombination of photogenerated electrons and holes and accelerate the transfer of photogenerated charge carriers, thus promoting the photocatalytic reaction process. [ABSTRACT FROM AUTHOR]

Background: Ticagrelor, the first reversible P2Y12 receptor antagonist, exhibits faster onset and offset of antiplatelet effects and more consistent platelet inhibition than clopidogrel in both healthy subjects and patients with stable coronary artery disease.Objective: The objectives of this study were to establish a population pharmacokinetics (PK) and pharmacodynamics (PD) model of ticagrelor and to provide a theoretical basis for the optimization of ticagrelor treatment in clinic.Methods: A single oral dose of 180 mg ticagrelor was administered to 14 healthy male subjects in a randomized study. Common single-nucleotide polymorphisms (SNPs) in biotransformation enzymes CYP3A4 and CYP3A5 (CYP3A4*1G and CYP3A5*3) were genotyped by PCR-direct sequencing. Blood samples were collected to measure plasma concentrations of ticagrelor and its active metabolite AR-C124910XX and maximal platelet inhibition. Various models were evaluated to characterize the pharmacokinetics of ticagrelor and AR-C124910XX as well as their PK-PD relationship. Covariates that may potentially affect PK or PD of ticagrelor and AR-C124910XX were included and assessed. Simulation for dosage regimen was performed based on the final PK-PD model.Results: Ticagrelor and AR-C124910XX PK were best described by a two-compartment model with first-order transit absorption model. CYP3A4*1G increased clearance for AR-C124910XX, but had no significant effect on ticagrelor clearance. The relationship between concentration and platelet response of ticagrelor was best described by a turnover model. Simulation results indicated that a lower dosage regimen of 30 mg maintenance dose (MD) could produce an anticipated anti-platelet response in comparison to the routine clinical dosage regimen (180 mg loading dose (LD), 90 mg MD).Conclusion: Our study developed a population PK-PD model for ticagrelor and further simulation for dosage regimen was performed based on the final model. Compared to the current recommended dosage regimen (180 mg LD, 90 mg MD), our simulation result of a relatively lower dose (30 mg MD) could also obtain an acceptable anti-platelet response, which may provide a reference for further dosage regimen design in Chinese population. [ABSTRACT FROM AUTHOR]

Identification of fermentation parameters affecting biomass and total fatty acid (TFA) production by thraustochytrid F24-2 was conducted using a Plackett-Burman experimental design. Factors influencing biomass accumulation were initial pH, sea salts, and glucose concentration. Additionally, temperature, initial pH, soy peptone, glucose, and sea salt concentration affected TFA production. Docosapentaenoic acid (n-6 DPA), palmitic acid (C16:0), and docosahexaenoic acid (DHA) were the predominant fatty acids produced. The best biomass (10.71 ± 0.04 g L−1), TFA (2.11 ± 0.07 g L−1), DHA (0.92 ± 0.04 g L−1), and C16:0 (0.65 ± 0.02 g L−1) concentrations were obtained at 25 °C with a medium adjusted to pH 7 and containing (per liter): 20 g glucose, 20 g soy peptone, 18 g sea salts, 0.2 g ammonium sulfate, 3 μg vitamin B12, 3 μg biotin, and 0.6 mg thiamine hydrochloride. Under these conditions, DHA production increased 18.5% in comparison to a complex medium previously used to grow thraustochytrid Thraustochytrium aureum ATCC 34304. [ABSTRACT FROM AUTHOR]

The prognosis of patients with malignant glioma is always quite poor, and this poor prognosis is probably due to our incomplete understanding of the molecular mechanisms underlying malignant glioma. It is known that myocyte enhancer factor-2D (MEF2D) plays an oncogenic role in hepatocellular carcinoma and promotes the survival of various types of cells. However, little is known about the expression profile and function of MEF2D in malignant glioma. In this study, we investigated the function and expression of MEF2D in malignant glioma. We found that in malignant glioma, there is an aberrantly high expression of MEF2D, which leads to poor prognosis of malignant glioma. The downregulation of MEF2D suppresses the proliferation of malignant glioma cell lines by inducing delay of S and G2/M phases of cell cycle and promoting apoptosis. Furthermore, the overexpression of MEF2D in astrocytes accelerates cell proliferation by regulating cell cycle progression. Furthermore, a mouse malignant glioma model demonstrated that MEF2D deficiency blocks malignant glioma formation in vivo. We conclude that MEF2D may act as a potential oncogene in malignant glioma and thus serve as a candidate target for malignant glioma therapy. [ABSTRACT FROM AUTHOR]

For quality control of Chinese herbal medicine (CHM), an attempt on fingerprint-efficacy study of Radix Aconiti Lateralis Preparata ( Fuzi) was developed in this paper. The fingerprints of Fuzi from various sources were determined by UPLC and hierarchical clustering analysis. Some quantitative thermo-kinetic parameters such as the heat-flow maximum power ( P) and its time corresponding to t, which obtained from the thermogenic curves of mitochondria metabolic activity affected by Fuzi were analyzed using principal component analysis. The fingerprint-efficacy relationship of chemical fingerprint and promoting effect of Fuzi were established using canonical correlation analysis. Our results showed that the sources and places of production of Fuzi had some significant influence on the chemical fingerprints and promoting metabolic effects of this CHM. Fingerprint-efficacy study provided a powerful way and some references for the quality control of Fuzi and other CHMs. [ABSTRACT FROM AUTHOR]

In this paper, based on the observer concept and adaptive control approach, we present a general and systematic research on estimating uncertain information in complex networks, which includes the unknown delays, node parameters and network topologies. Specifically, two novel approaches for simultaneous estimation of unknown coupling delays and node parameters, as well as the node delays and topology weights, are proposed and proved in this paper. Several typical examples are presented to verify the effectiveness of these approaches. The numerical results also show that the delay estimation approach is applicable for online monitoring of dynamical complex networks with time-varying delays. [ABSTRACT FROM AUTHOR]

Recently the synchronization control for chaotic systems with unknown parameters has attracted great attention among the researchers and diverse synchronization schemes have been reported in the literature. In this review article, we carefully revisit several recent articles published from 2010 to the present and find that several reported schemes are problematic. The imperfect synchronization schemes are categorized into five cases according to their defect types. By providing a general theorem for the adaptive synchronization design, we further present modified schemes to correct the defects in these articles. In addition, we have emphasized the significant linear independence condition for ensuring successful identification, as this condition has been neglected in several previous articles. We also summarize three cases when this condition is not valid, and accordingly four approaches are proposed to guarantee the successful parameter estimation for uncertain chaotic systems. [ABSTRACT FROM AUTHOR]

Modified function projective synchronization (MFPS), which generalizes many kinds of synchronization form, has received great attention recently. Based on the active control method and adaptive control technique, a general formula for designing the controllers is proposed to achieve adaptive MFPS, which corrects several incomplete results that have been reported recently. In addition, this paper derives the sufficient condition for parameter identification, which was not mentioned in much of the relevant literature concerning MFPS. Furthermore, we extend the MFPS scheme to the cases that the drive and response systems come with non-identical structures. The proposed method is both theoretically rigorous and practically feasible, which has the merits that it can not only achieve the full-state MFPS but also identify the fully unknown parameters in the synchronization process. The theoretical results are successfully applied to three typical illustrative cases: the adaptive MFPS of two identical 4-D hyperchaotic systems with unknown parameters in the response system, the adaptive MFPS between a 5-D hyperchaotic system and a 4-D hyperchaotic system with unknown parameters in the drive system and the adaptive MFPS between a 3-D chaotic system and a 4-D hyperchaotic system when the parameters in the drive system and response system are all unknown. For each case the controller functions and parameter update laws are well designed in detail. Moreover, the corresponding numerical simulations are presented, which agree well with the theoretical analysis. [ABSTRACT FROM AUTHOR]

Unsaturated medium-chain-length polyhydroxyalkanoates (MCL-PHA) were produced at a productivity of 0.63–1.09 g PHA l−1 h−1 with final PHA content ranging from 42.6 to 55.8% in single-stage, carbon-limited, fed-batch fermentations of Pseudomonas putida KT2440. A mixture of nonanoic acid (NA) and 10-undecenoic acid (UDA=) was fed exponentially to control growth rate. Varying the specific growth rate (0.14 h−1 vs. 0.23 h−1) at similar substrate feed ratios (NA:UDA= = 5:1) had little effect on the final PHA content and relative composition. However, decreasing the NA:UDA= ratio decreased the final amount of PHA produced from 56% with NA:UDA= = 5.07:1 to only 42% at NA:UDA= = 2.47:1. The molar fraction of all 3-hydroxyalkanoate monomers in the PHA product was relatively constant throughout each fermentation, indicating that the final product was homogeneous rather than a mixture of different copolymers. A linear relationship between unsaturation of the PHA produced and unsaturation of the carbon feed was found, which demonstrates the feasibility of producing unsaturated MCL-PHAs with controlled polymeric composition in a fed-batch process. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article "Percutaneous augmented instrumentation of unstable thoracolumbar burst fractures," in the December 2011 issue.