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Poly(ester-ether)s are biodegradable copolymers with excellent performance. These copolymers are used as scaffolds for tissue engineering and degradable materials in packaging. However, their synthesis procedures are generally tedious which restrict their widespread applications. Furthermore, the inadequate availability of their commercial monomers also hampers their production. Herein, we reported a facile strategy for the synthesis of linear and branched poly(ester-ether)s using a polyol and methyl acrylate (MA) as monomers. During the polymerisation, the vinyl bond of MA reacts with the hydroxyl groups of a polyol following an oxa-Michael polyaddition mechanism. Simultaneously, esterification takes place between the ester group of MA and polyol. As a result, poly(ester-ether)s were successfully synthesised by combining these two different types of reactions into one polymerisation system. The linear and branched structures of the products were confirmed by the nuclear magnetic resonance and triple-detector gel permeation chromatography. This work provides a facile strategy for the synthesis of poly(ester-ether)s from commercially available monomers. [ABSTRACT FROM AUTHOR]

Zeroing neural network (ZNN) model, an important class of recurrent neural network, has been widely applied in the field of computation and optimization. In this paper, two ZNN models with predefined-time convergence are proposed for the time-varying quadratic programming (TVQP) problem. First, in the framework of the traditional ZNN model, the first-order predefined-time convergent ZNN (FPTZNN) model is proposed in combination with a predefined-time controller. Compared with the existing ZNN models, the proposed ZNN model is error vector combined with sliding mode control technique. Then, the FPTZNN model is further extended and the second-order predefined-time convergent ZNN (SPTZNN) model is developed. Combined with the Lyapunov method and the concept of predefined-time stability, it is shown that the proposed FPTZNN and SPTZNN models have the properties of predefined-time convergence, and their convergence time can be flexibly adjusted by predefined-time control parameters. Finally, the proposed FPTZNN and SPTZNN models are compared with the existing ZNN models for the TVQP problem in simulation experiment, and the simulation experiment results verify the effectiveness and superior performance of the proposed FPTZNN and SPTZNN models. In addition, the proposed FPTZNN model for robot motion planning problem is applied and successfully implemented to verify the practicality of the model. • A first-order neural network model is established. • Further, a second-order neural network model is established. • Experiments with numerical example and robot motion planning problem. [ABSTRACT FROM AUTHOR]

Reverse osmosis (RO) membranes have been widely used in the field of membrane separation. However, most of the commercial RO membranes are fabricated based on a polysulphones- or polyethersulfone-modified polyethylene glycol terephthalate (PET) support, which are thick and exhibit poor solvent resistance. In this study, polyethylene (PE) battery membranes without any hydrophilic modification were directly used to prepare PE-RO membranes. The structures of the products were confirmed via attenuated total reflection Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and scanning electron microscopy. The resulting RO membrane prepared with 0.05 wt.% of trimesoyl chloride and 2 wt.% of m-phenylenediamine exhibited a water flux of 12.61 L m−2 h−1 with a desalination (NaCl) rate of 98.6%. The thickness of the PE-RO membrane is 80% of the thickness of the traditional RO membranes and hence has a wider application as a separation membrane. [ABSTRACT FROM AUTHOR]

Novel peroxide-initiating monomer with the peroxide group and the polymerizable vinyl double bond was designed and prepared through cheap industrial chemical reactants and facile synthesis. Here, one kind of the peroxide-initiating monomer 2-(tert-butylperoxy)ethyl methacrylate (BPEMA) prepared through three-step simple chemical reactions, using tert-butyl hydroperoxide and 2-bromoethanol as the raw ingredients, which reacted at low temperature and obtained the 2-tert-butyl peroxy ethanol, then esterified with methacryloyl chloride or isobutyryl chloride to obtain the peroxide-initiating monomer 2-(tert-butylperoxy)ethyl methacrylate(BPEMA). The analogue peroxide-initiating compound 2-(tert-butylperoxy)ethyl isobutyrate (BPEIB) was designed and obtained using the same reactions as those employed with BPEMA. The other kind of the peroxide-initiating monomer 2-hydroperoxide ethyl methacrylate (HPEMA). The purity of the three products was determined to be above 95%. Here, develop convenient and effective methods in using peroxide-initiating monomer for the in-depth study on the preparation of branched polymers. [ABSTRACT FROM AUTHOR]

Phenolic resin modified by triolein was synthesized by a two-step process. First, the modified resin was prepared by electrophilic addition reaction of phenol with triolein in acidic environment, then reacted with formaldehyde. The impact strength of modified phenolic resin increased by19~71% compared to that of pure phenolic resin. The maximum elongation at break of modified phenolic resin was higher by about 271% than that of pure phenolic resin. Toughness of modified phenolic resin was greatly improved through triolein treatment by bringing in the methylene, ester bond and aliphatic long chains. In terms of thermal properties, the addition of triolein has increased Tg of the modified phenolic resin a. The viscosity of phenolic resin also increased significantly by introducing triolein into phenolic resin. The preparation method developed here is simple and easy, which can expand the application of phenolic resin in adhesive production. [ABSTRACT FROM AUTHOR]

The existing model-based impedance learning control methods can provide variable impedance regulation for physical human–robot interaction (PHRI) in repetitive tasks without interactive force sensing, however, these methods require the completion of the repetitive tasks with constant time, which restricts their applications. For PHRI in repetitive tasks with different completion time, this paper proposes a spatial hybrid adaptive impedance learning control (SHAILC) strategy by using the spatial periodic characteristics of the tasks. In the spatial hybrid adaptation, spatial periodic adaptation is used for estimating time-varying human impedance and differential adaptation is designed for estimating robotic constant unknown parameters. The use of deadzone modifications in hybrid adaptation maintains the accuracy of the parameter estimation when the tracking error is small relative to the modeling error. The control stability is analyzed by a Lyapunov-based analysis in the spatial domain, and the control effectiveness and superiority is illustrated on a parallel robot in repetitive tasks with different task completion time. • Robot spatial dynamics is developed from robot temporal dynamics based on a defined spatial operator. • Spatial periodic adaptation and differential adaptation for estimating human impedance and robotic parameters,respectively. • The human impedance is disturbed spatial periodic. • Deadzone modifications in the hybrid adaptation maintains the accuracy of the parameter estimate. [ABSTRACT FROM AUTHOR]

Existing traditional Chinese medicine (TCM)-related databases are still insufficient in data standardization, integrity and precision, and need to be updated urgently. Herein, an Encyclopedia of Traditional Chinese Medicine version 2.0 (ETCM v2.0, http://www.tcmip.cn/ETCM2/front/#/) was constructed as the latest curated database hosting 48,442 TCM formulas recorded by ancient Chinese medical books, 9872 Chinese patent drugs, 2079 Chinese medicinal materials and 38,298 ingredients. To facilitate the mechanistic research and new drug discovery, we improved the target identification method based on a two-dimensional ligand similarity search module, which provides the confirmed and/or potential targets of each ingredient, as well as their binding activities. Importantly, five TCM formulas/Chinese patent drugs/herbs/ingredients with the highest Jaccard similarity scores to the submitted drugs are offered in ETCM v2.0, which may be of significance to identify prescriptions/herbs/ingredients with similar clinical efficacy, to summarize the rules of prescription use, and to find alternative drugs for endangered Chinese medicinal materials. Moreover, ETCM v2.0 provides an enhanced JavaScript-based network visualization tool for creating, modifying and exploring multi-scale biological networks. ETCM v2.0 may be a major data warehouse for the quality marker identification of TCMs, the TCM-derived drug discovery and repurposing, and the pharmacological mechanism investigation of TCMs against various human diseases. An updated ETCM v2.0 database may be a major data warehouse for quality marker identification and pharmacological mechanism investigation of TCMs against human diseases, and TCM-derived drug discovery and repurposing. [Display omitted] [ABSTRACT FROM AUTHOR]

Novel reducing emulsifier monomers 2-(dimethylamino)ethyl dodecyl maleate (DMAEDM) and 2-(dimethylamino)ethyl dodecyl itaconate (DMAEDI) containing polymerisable double bonds, tertiary amine and long-chain aliphatic hydrocarbons were creatively designed and synthesised. Reducing emulsifier monomers (REM) were prepared using dodecanol, acid anhydride and 2-dimethylaminoethyl chloride hydrochloride through a two-step reaction process. The optimum reaction temperature and ratio of chemicals were determined to achieve higher yield and purity of REM products. The product purity was above 95% as determined by gas chromatography. The structure of the products was confirmed by infrared spectroscopy (IR) and proton nuclear magnetic resonance (1H-NMR) spectroscopy. The novel reducing emulsifier monomers have been determined to have good emulsifying performance. [ABSTRACT FROM AUTHOR]

• AGNH displayed an obvious neuroprotection in rats with traumatic brain injury (TBI). • AGNH inhibited inflammation, cell apoptosis and pyroptosis. • Integrating transcriptome and metabolome revealed that AGNH inhibited NF-κB/NLRP3 axis and regulated glycerophospholipid metabolism to decrease TBI. Traumatic brain injury (TBI), especially neuroinflammation after TBI persists for a long time and causes significant neurodegenerative pathologies and neuropsychiatric problems. In this study, the neuroprotective effect of AnGong NiuHuang (AGNH) on TBI was investigated and the mechanism was revealed by integrating multiple omics. The rats with TBI were administrated with AGNH for 5 consecutive days and the effect was evaluated by using modified neurologic severity score (mNSS), brain edema, H&E staining, Nissl staining and TUNEL staining. The mechanism was revealed by using RNA sequencing (RNA-seq) and metabolomic analysis. The inflammatory factors, apoptosis-related proteins and identified vital targets were validated by enzyme-linked immunosorbent assay, western blotting and immunofluorescence staining. Administration of AGNH decreased mNSS, brain edema, brain structure damage, but increased Nissl body density in the rats with TBI. Additionally, AGNH reduced IL-1β, IL-17A, TNF-α, MMP9, MCP-1, IL-6, Bax and TUNEL staining,but elevated Bcl2 level. Integrating transcriptomic analysis and metabolomic analysis identified vital targets and critical metabolic pathways. Importantly, AGNH treatment reduced the expression of TLR4, MYD88, NLRP3, BTK, IL-18 and Caspase 1 as well as glycerophospholipid metabolism-related protein AGPAT2 and PLA2G2D, and decreased the nuclear translocation of NF-κB p65 in the brain of TBI rats. Additionally, AGNH increased phosphatidylcholine (PC), phosphatidylglycerol (PG), phosphatidylserine (PS), phosphatidylethanolamine (PE), but decreased 1-acyl-sn-glycero-3-phosphocholine (LysoPC) in the metabolic pathway of glycerophospholipid metabolism. Taken together, AGNH inhibited NF-κB/NLRP3 axis to suppress neuroinflammation, cell apoptosis and pyroptosis, and improved metabolic pathways of glycerophospholipid metabolism after TBI. [Display omitted] [ABSTRACT FROM AUTHOR]

Myocardial injury (MI) after acute ischemic stroke (AIS) poses a significant threat to patient prognosis. However, effective intervention strategies are currently lacking. To elucidate the mechanism of MI after AIS and effects of Naoxintong capsule (NXT) therapy. In vivo , after a rat model of middle cerebral artery occlusion (MCAO)-induced MI was established and assessed. NXT was administered prophylactically to evaluate its pharmacodynamic effects and mechanisms. In vitro , a noradrenaline (NA)-induced damage cell model was constructed. Subsequently, the NXT was applied to the cell models to examine its cardioprotective effects and potential mechanisms. The in vivo findings revealed that following MCAO, there was a notable upregulation of TH expression in the rat brain, which subsequently triggered an increase in serum levels of various biomarkers, including AD, NA, AST, cTnT, CK-MB, and NT-proBNP. Histological analysis employing H&E staining and TUNEL assay disclosed significant pathological alterations and an escalation in apoptotic activity within the myocardial tissue. The myocardial tissue exhibited elevated levels of MDA alongside diminished CAT activity. Additionally, a marked increase in the Bax/Bcl-2 ratio, Cytochrome C release, and Caspase-3 activation was observed, all of which are indicative of heightened apoptotic activity. Administration of the NXT intervention successfully attenuated TH expression in the brains of rats subjected to MCAO, consequently leading to a reduction in circulating levels of catecholamines (CAs). NXT also exhibited significant efficacy at ameliorating cardiac oxidative stress and reducing apoptosis. In vitro , stimulation with NA led to an increase in ROS levels and calcium ion concentration in H9c2 cardiomyocytes. However, the administration of NXT has been found to effectively alleviate these adverse effects, thereby protecting H9c2 cardiomyocytes from the deleterious consequences of oxidative stress and calcium dyshomeostasis. Overall, this study has demonstrated that increased CAs synthesis in the brain after AIS in experimental rats led to a surge in circulating CAs, ultimately leading to MI. NXT can alleviate MI due to cerebral ischemia by increasing improving brain catecholamine synthesis, cardiac oxidative stress, and apoptosis. The potential mechanism of NXT intervention on MI after AIS is multifaceted. NXT may ameliorate MI induced by AIS by improving oxidative stress levels, reducing cell apoptosis, and down-regulating the β1-AR-Gs-AC-cAMP-PKA pathway. simultaneously, NXT may regulate MI caused by AIS by reducing CAs synthesis in the brain by suppressing TH expression. Consequently, NXT exhibits a dual effect of simultaneously improving exacerbation of brain CAs synthesis and cardiac oxidative stress and apoptosis resulting from cerebral ischemia, ultimately alleviating AIS-induced MI. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • The treatment of fatty liver disease will become a new clinical indication for Maca. • Maca can intervene fatty liver disease by regulating fatty acids. • The changes of fatty acids can be used as a marker for the early diagnosis of AFLD. Lepidium meyenii (Maca) is a food and traditional herbal medicine derived from the roots of perennial plants cultivated at high altitudes in the Andes Mountains. Although many studies have shown the potential clinical value of maca, its integration into the existing clinical medical system remains a challenge. Therefore, this study used a combination of metabolomics and bioinformatics to accurately explore the characteristic metabolites of maca, which were verified in alcoholic fatty acid disease (AFLD) and nonalcoholic fatty acid disease (NAFLD) rat models, revealing the potential clinical efficacy of maca. Through subsequent quantitative analysis, we identified a new marker that may provide new ideas for subsequent clinical diagnosis of fatty liver. [ABSTRACT FROM AUTHOR]

A novel functional inimer 2-(2-bromoisobutyryloxy)ethyl methacrylate(BiBEM) both with the double bond and bromide was designed and synthesised. The branched polystyrene (PS) was prepared by the atom transfer radical polymerisation (ATRP), using BiBEM as inimer (initator) and CuBr complexed with bipyridine as catalysts in toluene at 80°C. The molecular weight and the branching degree of the polystyrene were analysed by using triple detection size-exclusion chromatography (TD-SEC) and the storage modulus in a wide and high-frequency range of polystyrene microrheological properties were studied by the diffusive wave spectroscopy (DWS). By adjusting the ratio of inimer to catalysts, a series of branched polystyrene polymers with different molecular weight and branching degree were obtained. The increase of the BiBEM concentration led to a higher degree of branching, while higher molecular weight and broader molecular weight distribution are accompanied. The branched polystyrene showed low storage modulus and lower chain entanglement compared to linear analogues. [ABSTRACT FROM AUTHOR]

Tadpole-like single-chain particle (TSCP) with a crosslinked PDMAEMA (poly(2-dimethylaminoethyl methacrylate)) chain as the head and a tethered POEGMA (oligo(ethylene glycol) monomethyl ether methacrylate) chain as the tail was fabricated by intra-chain crosslinking of PDMAEMA chain of the copolymer POEGMA-b-PDMAEMA (POD). In the selective solvent for the tail, TSCPs formed worm-like micelles, thin films and tubular vesicles in DMF/H2O (1/4, v/v). Different from the traditional one-shot response to ultrasonic treatment, the tubular vesicles underwent rapid structural transformations to spherical vesicles under gentle ultrasonic treatment and fragments under an enhanced ultrasonic treatment. The unique multi-level ultrasonic response behaviour makes the assemblies promising drug carriers featured with the remote and stepwise controlling release of drugs. [ABSTRACT FROM AUTHOR]

[Display omitted] Amino acids (AAs) metabolism profiles in brain play a pivotal role in cerebral ischemia (CI), which is a complex, spatial and temporal event. NaoXinTong Capsules (NXT) are widely prescribed in Chinese medicine for the treatment of cerebrovascular and cardiovascular diseases. In this study, a novel analytical method for the quantification of twenty-three AAs in cortex and hippocampus was developed by UPLC-QQQ-MS. Based on middle cerebral artery occlusion (MCAO) rat model, the cerebral infarction and the neurological behavior scores are firstly dynamically evaluated at 3, 12, and 24 h after CI. Then the dynamic levels of the AAs in cortex and hippocampus were analyzed respectively after CI. After CI, MCAO rats showed neurological deficits especially at 24 h. Based on PCA scores plot at different time after CI, the time of the AAs metabolism showing an obvious disturbance in the cortex (12 and 24 h after ischemia) is earlier than that in the hippocampus (24 h after ischemia). Based on the fold-changes of MCAO vs. sham group and receiver operating curve (ROC) analysis, a total of nine AAs biomarkers, with continuous and consistent changes at different time points after CI, were finally obtained including eight AAs of Ala, GABA, Pro, Val, Ile, His, Cit and Leu in the cortex, and three AAs of Ile, Asp, and Cit in the hippocampus. After NXT treatment, the efficacy was confirmed by reducing cerebral infarction and improving the neurological behavior scores. Furthermore, GABA, Pro, His, Leu, Asp, Ile and Cit were found to exhibited an obvious tendency for returning to baseline values in the corresponding regions at 24 h after CI (P < 0.05). This study provides new strategies to explore the mechanism of CI and help discover the potential mechanism of NXT. [ABSTRACT FROM AUTHOR]

This paper proposes a saturated smooth adaptive controller for regulating a certain type of underactuated Euler–Lagrange systems (UELSs) with modeling uncertainties and control saturations based on a singular perturbation approach. Compared with relevent literature, the advantages of the proposed controller include: (1) it renders the UELS semiglobally asymptotically track the desired position without the violation of control input constraints; (2) high-order derivatives of positions are not required in its implementation. The Hoppensteadt's Theorem is employed to show that the proposed saturated controller renders the UELS semiglobally asymptotically stable about the desired set point with the satisfaction of control input constraints. The control effectiveness is validated by simulations on a two-link compliant robot arm. • A saturated adaptive controller is proposed for underactuated Euler–Lagrange systems. • An adaptive estimator with a prior designed bound is proposed for the gravitational torque. • A proportional-derivative control term is designed for the slow-varying subsystem. • The Hoppensteadt's Theorem is applied to prove semiglobal asymptotical stability. [ABSTRACT FROM AUTHOR]

The photoisomerisation behaviour of Poly(N-isopropylacrylamide) end-capped with 4-propoxyazobenzene (PNIPAM-Azo-OC3H7) was studied in a conconsolvent mixture of water and dioxane. The trans-cis isomerisation rate of PNIPAM-Azo-OC3H7 was mildly affected by the solvent compositions. Interestingly, the addition of dioxane could not only change the lower critical solution temperature (LCST) of PNIPAM-Azo-OC3H7 aqueous solution but also accurately controlled the increase or decrease in the LCST during UV irradiation. The LCST change (ΔT) could be adjusted from −5.0°C to 10.0°C, which was affected by the cononsolvent type, the second solvent and polymer concentration. Transmission electron micrographs (TEMs) showed that the PNIPAM-Azo-OC3H7 solution could self-assemble into different nano-micelles in different amounts of miscible solvents. UV irradiation of PNIPAM-Azo-OC3H7 solution was found to induce different changes in particle shape and size, which in turn led to either decrease or increase in the LCST changes in this novel responsive system. Furthermore, Nile red was tested here as a fluorescence probe for photo-induced release from PNIPAM-Azo-OC3H7 micelles, and the results suggested that this polymer could be used as a hydrophobic chemotherapeutic drug carrier for controlled release. [ABSTRACT FROM AUTHOR]

Tertiary amine-structured compounds containing stimulating response groups such as diethylaminoethyl isobutyrate and N-(2-(dimethylamino)ethyl)methyl, were synthesised by an acid chloride esterification method using acrylamide, N-(2-(dimethylamino) ethyl)isobutyramide, 2-methyl-N-[3-(methyl-phenyl-amino)-propyl]-acrylamide and 2-Methyl -N-[3-(methyl-phenyl-amino)-propyl]-propionamide reactants. The effects of different ratios of reactants on product purity, reaction time on purity and yield were investigated. Product purity was characterised by gas chromatography. The structure was characterised by infrared spectroscopy (IR) and proton nuclear magnetic resonance (1H-NMR), and the purity of the five different synthesised compounds was determined to be more than 97%. This study provides a convenient and efficient method for the synthesis of compounds containing tertiary amine structures. [ABSTRACT FROM AUTHOR]

Over the past decade, traditional Chinese medicine (TCM) has widely embraced systems biology and its various data integration approaches to promote its modernization. Thus, integrative pharmacology-based traditional Chinese medicine (TCMIP) was proposed as a paradigm shift in TCM. This review focuses on the presentation of this novel concept and the main research contents, methodologies and applications of TCMIP. First, TCMIP is an interdisciplinary science that can establish qualitative and quantitative pharmacokinetics–pharmacodynamics (PK–PD) correlations through the integration of knowledge from multiple disciplines and techniques and from different PK–PD processes in vivo. Then, the main research contents of TCMIP are introduced as follows: chemical and ADME/PK profiles of TCM formulas; confirming the three forms of active substances and the three action modes; establishing the qualitative PK–PD correlation; and building the quantitative PK–PD correlations, etc. After that, we summarize the existing data resources, computational models and experimental methods of TCMIP and highlight the urgent establishment of mathematical modeling and experimental methods. Finally, we further discuss the applications of TCMIP for the improvement of TCM quality control, clarification of the molecular mechanisms underlying the actions of TCMs and discovery of potential new drugs, especially TCM-related combination drug discovery. This review focuses on the presentation of the novel concept and the main research contents, methodologies and applications of integrative pharmacology-based traditional Chinese medicine. [Display omitted] [ABSTRACT FROM AUTHOR]