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Liver fibrosis is a disease with complex pathological mechanisms. Penthorum chinense Pursh (P. chinense) is a traditional Chinese medicine (TCM) for liver injury treatment. However, the pharmacological mechanisms of P. chinense on liver fibrosis have not been investigated and clarified clearly. This study was designed to investigate the chemicals in P. chinense and explore its effect on liver fibrosis. First, we developed a highly efficient method, called DDA-assisted DIA, which can both broaden mass spectrometry (MS) coverage and MS2 quality. In DDA-assisted DIA, data-dependent acquisition (DDA) and data-independent acquisition (DIA) were merged to construct a molecular network, in which 1,094 mass features were retained in Penthorum chinense Pursh (P. chinense). Out of these, 169 compounds were identified based on both MS1 and MS2 analysis. After that, based on a network pharmacology study, 94 bioactive compounds and 440 targets of P. chinense associated with liver fibrosis were obtained, forming a tight compound–target network. Meanwhile, the network pharmacology experimental results showed that multiple pathways interacted with the HIF-1 pathway, which was first identified involved in P. chinense. It could be observed that some proteins, such as TNF-α, Timp1, and HO-1, were involved in the HIF-1 pathway. Furthermore, the pharmacological effects of P. chinense on these proteins were verified by CCl4-induced rat liver fibrosis, and P. chinense was found to improve liver functions through regulating TNF-α, Timp1, and HO-1 expressions. In summary, DDA-assisted DIA could provide more detailed compound information, which will help us to annotate the ingredients of TCM, and combination with computerized network pharmacology provided a theoretical basis for revealing the mechanism of P. chinense.

Liver fibrosis is a disease with complex pathological mechanisms.

Aiming at the influence of the nonlinearity of the motor of the fast mirror platform mechanism and the complex coupling between the platform azimuth and pitch frames on the fast mirror mechanism, a decoupling control technology based on state space feedback is proposed in this paper. Firstly, according to the dynamic model of the azimuth and pitch frame of the fast mirror platform, the state space equation is established, and the state space variables of the system are obtained. The constructed feedback system is connected in series with the original system to obtain a pseudo linear system, so that the original coupled nonlinear multi output system is transformed into two linear decoupled single input single output subsystems, In order to eliminate the complex coupling of the azimuth and pitch frame of the fast mirror platform mechanism. Finally, the system simulation platform is established in Matlab/Simulink. The results show that the decoupling technology of fast mirror platform based on state space feedback designed in this paper can effectively reduce the coupling between platform azimuth and pitch frames and improve the stability accuracy of the platform.

This paper describes the synthesis of two new blue to transmissive donor-acceptor electrochromic polymers: a polymer synthesized using an alternating copolymerization route (ECP-Blue-A) and a polymer synthesized using a random copolymerization (ECP-Blue-R) by Stille polymerization. These polymers utilize side chains with four ester groups per donor moiety, allowing organic solubility in the ester form, and water solubility upon saponification to their carboxylate salt form. We demonstrate that the saponified polymer salts of ECP-Blue-A and ECP-Blue-R (WS-ECP-Blue-A and WS-ECP-Blue-R) can be processed from aqueous solutions into thin films by spray-casting. Upon the subsequent neutralization of the thin films, the resulting polymer acid films are solvent resistant and can be electrochemically switched between their colored state and a transmissive state in a KNO(3)/water electrolyte solution. The polymer acids, WS-ECP-Blue-A-acid and WS-ECP-Blue-R-acid, show electrochromic contrast Δ%T of 38% at 655 nm and 39% at 555 nm for a 0.5 s switch, demonstrating the advantage of an aqueous compatible electrochrome switchable in high ionic conductivity aqueous electrolytes. The results of the electrochromic properties study indicate that these polymers are promising candidates for aqueous processable and aqueous switching electrochromic materials and devices as desired for applications where environmental impact is of importance.

As electrochromic polymers can switch with a high transmittance contrast in the sub-second time frame, an analytical tool to rapidly probe the electrochemically-induced optical transition is required for characterization of these materials for electronic displays and smart windows. A novel technique is described to synchronize the electrochemical and optical measurements by utilizing an external trigger to facilitate coordinated communication between the potentiostat, which applies a voltage to the electrode supported electrochromic polymers, and the optical spectrometer that records the induced optical transitions. By using a spectrometer containing a photodiode array detector, these measurements are capable of rapid data acquisition to track the electrochromic change in the polymer films, with as many as 500 spectra captured during a one-second switch of the polymer from a colored, neutral to highly transmissive state. Additionally, with this rapid, full-spectral measurement, it is possible to trace the temporal evolution of the electrochromic change to determine the presence of intermediate color tones, as well as their duration. Here, three polymers are shown, ECP-Magenta, ECP-Green, and ECP-Black, which obtain high transmittance contrast between 40 to 50 Δ%T, with sub-second switching times measured in the range of 400 to 700 ms, demonstrating their potential for use in electrochromic windows and displays where rapid transitions are desired.

A family of multi-heterocycle donor–acceptor–donor (DAD) telechelic conjugated oligomers designed for two-photon absorption (2PA) and emission in the near-infrared (near-IR) were prepared, and the relationship between their spectral, structural, and electrochemical properties were investigated. These oligomers, based on electron-rich thiophene, phenylene, and 3,4-ethylenedioxythiophene (EDOT) units as donors along with electron-deficient benzothiadiazole or its derivative units as acceptors, have been characterized through linear absorbance and fluorescence measurements, nonlinear absorbance, cyclic voltammetry, and differential pulse voltammetry to demonstrate the evolution of narrow HOMO–LUMO gaps ranging from 1.05 to 1.95 eV, with the oligomers composed of EDOT and benzo[1,2-c,3,4-c′]bis[1,2,5]thiadiazole (BBT) exhibiting the narrowest gap. The absorption maxima ranges from 517 to 846 nm and the fluorescence maxima ranges from 651 to 1088 nm for the different oligomers. Z-scan and two-photon fluorescen...

A novel reversible addition-fragmentation transfer (RAFT) agent, 10-carboxylic acid-10-dithiobenzoate-decyltrimethylammonium bromide (CDDA), was synthesized and intercalated into montmorillonite (MMT). Successively, the CDDA-intercalated MMT was used as RAFT agent in the in situ RAFT polymerization for preparation of the polystyrene/MMT nanocomposites. After separation of MMT, the polymers obtained have predictable molecular weight and narrow polydispersity. XRD spectra and TEM images of the nanocomposites demonstrated exfoliated structure. Thermal stability of the composites has been noticeably improved.

Poly(ethylene oxide) methyl ether/polystyrene/poly( l -lactide) (MPEO/PSt/PLLA) ABC miktoarm star copolymers were synthesized by combination of reversible addition–fragmentation transfer (RAFT) polymerization and ring-opening polymerization (ROP) using bifunctional macro-transfer agent, MPEO with two terminal dithiobenzoate and hydroxyl groups. It was prepared by reaction of MPEO with maleic anhydride (MAh), subsequently reacted with dithiobenzoic acid and ethylene oxide. RAFT polymerization of St at 110 °C yielded block copolymer, MPEO-b-PSt [(MPEO)(PSt)CH2OH], and then it was used to initiate the polymerization of l -lactide in the presence of Sn(OCt)2 at 115 °C to produce ABC miktoarm star polymers, s-[(MPEO)(PSt)(PLLA)]. The structures of products obtained at each synthetic step were confirmed by NMR and gel permeation chromatography data.

The H-shaped copolymers (PSt)2PEG(PSt)2, which are constructed by attaching two polystyrene branches to both ends of poly(ethylene glycol), were synthesized by atom transfer radical polymerization ...

Amphiphilic block comb-shaped copolymers, poly[poly(ethylene oxide) methyl ether acrylate]-block-polystyrene [P(A-MPEO)-block-PSt] with PSt as a handle, were successfully synthesized via a macromonomer technique. The reaction of MPEO with acryloyl chloride yielded a macromonomer, A-MPEO. The macroinitiator PSt capped with the dithiobenzoate group (PSt-SC(S)Ph) was prepared by reversible addition–fragmentation transfer (RAFT) polymerization of styrene in the presence of benzyl dithiobenzoate, and used as macroinitiator in the controlled radical block copolymerization of A-MPEO at room temperature under 60Co irradiation. After the unreacted macromonomer A-MPEO had been removed by washing with hot saturated saline water, block comb-shaped copolymers were obtained. Their structure was characterized by 1H NMR spectroscopy and gel permeation chromatography. The phase transition and self-assembling behaviour were investigated by atomic force microscope and differential scanning calorimetry. Copyright © 2004 Society of Chemical Industry