Synthesis and controlled radical polymerization of multifunctional monomers

Multifunctional monomers on the basis of acryl- and methacryl derivatives were synthesized and different protective groups were used. After polymerization the protective groups were removed by different methods. Various initiators for the NMP of the monomers were synthesized and the reaction conditions were optimized. The results showed that NMP was not a suitable method for multifunctional acryl- and methacryl derivatives to achieve well-defined homopolymers, although it was successful for control of polymerization of styrene and block copolymerization of multifunctional acryl- and methacryl derivatives with alkoxyamine terminated polystyrene. The ATRP of multifunctional acrylates and methacrylates has been successfully performed, as well as the block copolymerization of multifunctional acrylates and methacrylates. Relatively low polydispersities of the corresponding polymers (PD=1.18-1.36) and reasonably high rates of polymerization could be achieved when Me6TREN and PMDETA were used as ligands. However, the ATRP of multifunctional acrylamides and methacrylamides failed. The RAFT-polymerization of styrene, acrylamide and acrylate using BDTB as a CTA and AIBN as an initiator afforded polymers with narrow molecular weight distribution (PD=1.13-1.26). A kinetic investigation and the further synthesis of block copolymers using dithioester-terminated homopolymers as macroCTAs showed that the RAFT polymerization of acrylamide M9b proceeded in a living manner. However, BDTB does not control the reaction of methacrylic monomers, such as methacrylates and methacrylamides. The bulk phase behavior of the block copolymers were examined by means of DSC and the surface behaviors of block copolymers as thin layers were examined with AFM. Two-phase transitions in the block copolymers were observed clearly by DSC, indicative of the appearance of phase separations, which were seen in an AFM image. In conclusion, multifunctional acryl- and methacryl derivatives failed to achieve well-defined homopolymers by NMP. However, this method was successful for block copolymerization of multifunctional acryl- and methacryl derivatives with alkoxyamine terminated polystyrene. Multifunctional acrylates and methacrylates were successfully homopolymerized and block copolymerized by ATRP. Multifunctional acrylates and acrylamides were suitable for homopolymerization and block copolymerization by the RAFT process. Thus far, it is difficult to homopolymerize multifunctional methacrylamides in controlled way

Nanoscaled Fluorescent Films and Layers for Detection of Environmental Pollutants

Hazardous gas and ion pollutants are the most serious environmental problems around the world. It is of great importance to develop devices for easy detection of these hazardous substances. Fluorescence technology with high resolution and operational simplicity has attracted a lot of attention in recent years. Organic fluorescent dyes absorb/emit lights within a broad wavelength range, which is suitable for various demands. Chromophores, such as perylene, cyanine dyes, spiropyran, and so on, are widely studied as fluorescent probes for gases and ions. The dyes could respond to external stimuli through structural changes of the conjugated chromophore itself or the attached functional groups, leading to detectable spectral changes. Organic dyes are incorporated into nanoscaled films and layers, which are portable and durable for effective sensing in complex environments. In this chapter, preparation and application of fluorescent films and layers (FFL) for gaseous/ionic detection are reviewed. We discuss the response mechanism of fluorescent dyes, the fabrication of nanoscaled FFL, and some examples of FFL for the detection of gas and ion pollutants

Amphiphilic Ionic Perylenediimides: Structures, Self-Assembly Studies and Biomedical Applications

Amphiphilic ionic perylenediimides (AIPDIs) with well‐defined structures have been widely studied, which involve abundant non‐covalent interactions. Among these interactions, electrostatic interactions serve as the primary force that may be followed by other non‐covalent interactions like π–π stacking. Taking advantage of these tunable interactions between simple AIPDI‐building blocks, AIPDIs are widely used for constructing increasingly complex structures at varying scales. Besides, AIPDIs with outstanding photochemical stability exhibit high fluorescence quantum yields (FQYs) in aqueous solution, because hydrophilic substituents of AIPDIs can shield the inner perylene chromophores and weaken π–π stacking, contributing to the improvement of water solubility and the suppression of aggregation‐caused quenching (ACQ). AIPDIs with excellent water solubility, strong FQYs and desired interactions with charged components in cells and tissues hold great promise for various biomedical applications, which can be concluded in three hierarchical levels, which is in vitro, live cell and tissue

High-efficiency green management of potato late blight by a self-assembled multicomponent nano-bioprotectant

Abstract Potato late blight caused by Phytophthora infestans is a devastating disease worldwide. Unlike other plant pathogens, double-stranded RNA (dsRNA) is poorly taken up by P. infestans, which is a key obstacle in using dsRNA for disease control. Here, a self-assembled multicomponent nano-bioprotectant for potato late blight management is designed based on dsRNA and a plant elicitor. Nanotechnology overcomes the dsRNA delivery bottleneck for P. infestans and extends the RNAi protective window. The protective effect of nano-enabled dsRNA against infection arises from a synergistic mechanism that bolsters the stability of dsRNA and optimizes its effective intracellular delivery. Additionally, the nano-enabled elicitor enhances endocytosis and amplifies the systemic defense response of the plants. Co-delivery of dsRNA and an elicitor provides a protective effect via the two aspects of pathogen inhibition and elevated plant defense mechanisms. The multicomponent nano-bioprotectant exhibits superior control efficacy compared to a commercial synthetic pesticide in field conditions. This work proposes an eco-friendly strategy to manage devastating plant diseases and pests

Thermal-Enhanced bri1-301 Instability Reveals a Plasma Membrane Protein Quality Control System in Plants

Brassinosteroids (BRs) are essential phytohormones mainly perceived by a single-pass transmembrane receptor-like protein kinase (RLK), BRASSINOSTEROID INSENSITIVE 1 (BRI1). bri1-5 and bri1-9, two distinct mutants with point mutations in the extracellular domain of BRI1, show weak defective phenotypes. Previous studies indicated that bri1-5 and bri1-9 mutated proteins can be recognized and eliminated via an endoplasmic reticulum quality control (ERQC) mechanism. Most of these two proteins, therefore, cannot reach their destination, plasma membrane. Here, we report our functional characterization of bri1-301, another BRI1 mutant protein with an amino acid substitution in the cytoplasmic kinase domain. bri1-301 is a partially functional BR receptor with significantly decreased protein abundance. Interestingly, protein stability and subcellular localization of bri1-301 are temperature-sensitive. At 22°C, an optimal temperature for indoor Arabidopsis growth, bri1-301 shows a weak defective phenotype. At a lower temperature condition such as 18°C, bri1-301 exhibits subtle morphological defects. At a higher temperature condition such as 28°C, on the other hand, bri1-301 displays an extremely severe phenotype reminiscent to that of a null bri1 mutant due to greatly increased bri1-301 internalization and degradation. Our detailed analyses suggest that bri1-301 stability is controlled by ERQC and plasma membrane quality control (PMQC) systems. Since PMQC has not been well studied in plants, bri1-301 can be used as a model mutant for future genetic dissection of this critical process

Adenoid lymphocyte heterogeneity in pediatric adenoid hypertrophy and obstructive sleep apnea

IntroductionAdenoid hypertrophy is the main cause of obstructive sleep apnea in children. Previous studies have suggested that pathogenic infections and local immune system disorders in the adenoids are associated with adenoid hypertrophy. The abnormalities in the number and function of various lymphocyte subsets in the adenoids may play a role in this association. However, changes in the proportion of lymphocyte subsets in hypertrophic adenoids remain unclear.MethodsTo identify patterns of lymphocyte subsets in hypertrophic adenoids, we used multicolor flow cytometry to analyze the lymphocyte subset composition in two groups of children: the mild to moderate hypertrophy group (n = 10) and the severe hypertrophy group (n = 5).ResultsA significant increase in naïve lymphocytes and a decrease in effector lymphocytes were found in severe hypertrophic adenoids.DiscussionThis finding suggests that abnormal lymphocyte differentiation or migration may contribute to the development of adenoid hypertrophy. Our study provides valuable insights and clues into the immunological mechanism underlying adenoid hypertrophy

Synthesis and controlled radical polymerization of multifunctional monomers

Multifunctional monomers on the basis of acryl- and methacryl derivatives were synthesized and different protective groups were used. After polymerization the protective groups were removed by different methods. Various initiators for the NMP of the monomers were synthesized and the reaction conditions were optimized. The results showed that NMP was not a suitable method for multifunctional acryl- and methacryl derivatives to achieve well-defined homopolymers, although it was successful for control of polymerization of styrene and block copolymerization of multifunctional acryl- and methacryl derivatives with alkoxyamine terminated polystyrene. The ATRP of multifunctional acrylates and methacrylates has been successfully performed, as well as the block copolymerization of multifunctional acrylates and methacrylates. Relatively low polydispersities of the corresponding polymers (PD=1.18-1.36) and reasonably high rates of polymerization could be achieved when Me6TREN and PMDETA were used as ligands. However, the ATRP of multifunctional acrylamides and methacrylamides failed. The RAFT-polymerization of styrene, acrylamide and acrylate using BDTB as a CTA and AIBN as an initiator afforded polymers with narrow molecular weight distribution (PD=1.13-1.26). A kinetic investigation and the further synthesis of block copolymers using dithioester-terminated homopolymers as macroCTAs showed that the RAFT polymerization of acrylamide M9b proceeded in a living manner. However, BDTB does not control the reaction of methacrylic monomers, such as methacrylates and methacrylamides. The bulk phase behavior of the block copolymers were examined by means of DSC and the surface behaviors of block copolymers as thin layers were examined with AFM. Two-phase transitions in the block copolymers were observed clearly by DSC, indicative of the appearance of phase separations, which were seen in an AFM image. In conclusion, multifunctional acryl- and methacryl derivatives failed to achieve well-defined homopolymers by NMP. However, this method was successful for block copolymerization of multifunctional acryl- and methacryl derivatives with alkoxyamine terminated polystyrene. Multifunctional acrylates and methacrylates were successfully homopolymerized and block copolymerized by ATRP. Multifunctional acrylates and acrylamides were suitable for homopolymerization and block copolymerization by the RAFT process. Thus far, it is difficult to homopolymerize multifunctional methacrylamides in controlled way

Synthesis and controlled radical polymerization of multifunctional monomers

Multifunctional monomers on the basis of acryl- and methacryl derivatives were synthesized and different protective groups were used. After polymerization the protective groups were removed by different methods. Various initiators for the NMP of the monomers were synthesized and the reaction conditions were optimized. The results showed that NMP was not a suitable method for multifunctional acryl- and methacryl derivatives to achieve well-defined homopolymers, although it was successful for control of polymerization of styrene and block copolymerization of multifunctional acryl- and methacryl derivatives with alkoxyamine terminated polystyrene. The ATRP of multifunctional acrylates and methacrylates has been successfully performed, as well as the block copolymerization of multifunctional acrylates and methacrylates. Relatively low polydispersities of the corresponding polymers (PD=1.18-1.36) and reasonably high rates of polymerization could be achieved when Me6TREN and PMDETA were used as ligands. However, the ATRP of multifunctional acrylamides and methacrylamides failed. The RAFT-polymerization of styrene, acrylamide and acrylate using BDTB as a CTA and AIBN as an initiator afforded polymers with narrow molecular weight distribution (PD=1.13-1.26). A kinetic investigation and the further synthesis of block copolymers using dithioester-terminated homopolymers as macroCTAs showed that the RAFT polymerization of acrylamide M9b proceeded in a living manner. However, BDTB does not control the reaction of methacrylic monomers, such as methacrylates and methacrylamides. The bulk phase behavior of the block copolymers were examined by means of DSC and the surface behaviors of block copolymers as thin layers were examined with AFM. Two-phase transitions in the block copolymers were observed clearly by DSC, indicative of the appearance of phase separations, which were seen in an AFM image. In conclusion, multifunctional acryl- and methacryl derivatives failed to achieve well-defined homopolymers by NMP. However, this method was successful for block copolymerization of multifunctional acryl- and methacryl derivatives with alkoxyamine terminated polystyrene. Multifunctional acrylates and methacrylates were successfully homopolymerized and block copolymerized by ATRP. Multifunctional acrylates and acrylamides were suitable for homopolymerization and block copolymerization by the RAFT process. Thus far, it is difficult to homopolymerize multifunctional methacrylamides in controlled way

Jointly improving energy efficiency and smoothing power oscillations of integrated offshore wind and photovoltaic power: a deep reinforcement learning approach

Abstract This paper proposes a novel deep reinforcement learning (DRL) control strategy for an integrated offshore wind and photovoltaic (PV) power system for improving power generation efficiency while simultaneously damping oscillations. A variable-speed offshore wind turbine (OWT) with electrical torque control is used in the integrated offshore power system whose dynamic models are detailed. By considering the control system as a partially-observable Markov decision process, an actor-critic architecture model-free DRL algorithm, namely, deep deterministic policy gradient, is adopted and implemented to explore and learn the optimal multi-objective control policy. The potential and effectiveness of the integrated power system are evaluated. The results imply that an OWT can respond quickly to sudden changes of the inflow wind conditions to maximize total power generation. Significant oscillations in the overall power output can also be well suppressed by regulating the generator torque, which further indicates that complementary operation of offshore wind and PV power can be achieved