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Abstract: The Southeast Asian region is remarkably vulnerable to natural disasters which repeatedly cause devastations to both human lives and properties. However, current disaster relief efforts have not lived up to the high standards. Even worse is that humanitarian efforts have been frequently frustrated by the rejections from national authorities under the name of “sovereignty”. All these problems necessitate a widely accepted, politically neutral, well coordinated and effectively governed organization within the region. We, hereby propose a Disaster Response Training and Logistic Centre under the umbrella of the Association of Southeast Asian Nations (ASEAN), which aims to mitigate the devastation of disasters, to provide accurate relief assessment, and training for relief team on a regular basis, and to allocate and mobilize humanitarian aid. The Centre will be endorsed through an agreement by all ASEAN governments. The philosophy underpinning the organization reflects a regional approach whereby stronger government involvement and regional integration in disaster relief is indispensable in the context of the Southeast Asian region.

This study synthesized and characterized different proportions of nonestrogenic di(meth)acrylate 9,9-bis[4-((2-(2-methacryloyloxy)ethyl-carbamate)ethoxy)phenyl] fluorine (Bis-EFMA)-based resin composite systems to study their physical, chemical, optical and biological characteristics, and adhesive properties after bonding to a tooth. The estrogenic activity of raw materials was evaluated and compared with estrogen and commercial bisphenol A. After photopolymerization, all resin composite systems were prepared, and their properties were systematically investigated. Notably, the nonestrogenic di(meth)acrylate Bis-EFMA exhibited a more suitable refractive index, excellent biocompatibility, low marginal microleakage and improved bonding strength. Except for the pure UDMA and Bis-EFMA groups, the depth of cure and Vickers microhardness ratios of all the other groups met the requirements of bulk filling (one-time curing depth of more than 4 mm). Bis-EFMA resin systems exhibited lower volumetric polymerization shrinkage (about 3–5%), higher curing depth (>6 mm in specific proportions), mechanical properties (flexural strength of 120–130 MPa, etc.), and microtensile bonding strength (>27.8 MPa), which were comparable or superior to Bis-GMA or commercial composites. Herein, we believe that the novel nonestrogenic di(meth)acrylate (Bis-EFMA) has a wide application prospect as an alternative to Bis-GMA.

To address the disadvantages of traditional rubber antioxidants with low molecular weight such as easy migration, poor extraction resistance, low thermal stability and antioxidant efficiency, in this work, we first prepared an antioxidant containing primary and secondary antioxidant groups (MC-MPA) through thiol-ene click reaction between N-(4-aminophenyl)maleimide (MC) and 3-mercaptopropionic acid (MPA). Then, we synthesized a chitosan-based macromolecular antioxidant with long-chain alkene, aromatic secondary amine, and thioether groups (COS-UC-MC-MPA) by sequentially grafting functional compounds 10-undecanonyl chloride (UC) and antioxidant MC-MPA onto natural macromolecular polymer chitosan (COS). The free radical scavenging ability of COS-UC-MC-MPA was assessed by using 2,2-Diphenyl-1-picrylhydrazyl (DPPH), and the results demonstrated that COS-OC-MC-MPA has high scavenging rate of 76.5 % for DPPH free radicals after 1 min of contact with DPPH dimethyl sulfoxide solution, showing excellent free radical scavenging ability. In addition, the results of accelerated thermo-oxidative aging test, thermogravimetric (TG) test, kinetic analysis of thermal-oxidative degradation, extraction resistance test, and volatilization resistance test indicated that COS-UC-MC-MPA with superior migration resistance and volatilization resistance could effectively enhance the antioxidative properties, thermal stability and thermal-oxidative stability of rubber composites. Moreover, the results of rubber processibility analysis (RPA) test and scanning electron microscopy (SEM) implied that the addition of COS-UC-MC-MPA is also conductive to improving the dispersibility of silica in rubber matrix. This study supplies a new perspective for the preparation of environmentally friendly and highly efficient macromolecular antioxidants for rubber composites.

Cathodic electrophoretic deposition (CED) coatings are inevitably scratched following their application in processes such as automotive finishing. Self-healing coatings possess the ability to repair micro-scale damage, thereby extending their service life and reducing maintenance costs. Here, a novel strategy was developed to synthesize room-temperature intrinsic self-healing CED coatings by inserting 2-aminophenyl disulfide (APDS) into the polymer chain of cationic waterborne polyurethane (CWPU). Emulsion films incorporating the disulfide (SCWPU) could self-heal at room temperature via dynamic disulfide bond exchange and hydrogen bonding interactions, and their structures were confirmed by FTIR and Raman spectroscopy. The thermal properties of the SCWPU films were determined by differential scanning calorimetry and thermal gravimetric analysis. The effects of APDS incorporation and hard segment content (HSC) on the self-healing ability, mechanical and emulsion properties of the SCWPU films were systematically investigated. The results showed that the self-healing abilities of SCWPU film were 97.2% at RT over 24 h and 96.5% at 37°C (body temperature) after 4 h. CED coatings (8 μm, 3H pencil hardness) prepared from SCWPU emulsion also displayed self-healing properties at room temperature.

A series of antibacterial styrene-acrylic emulsions (SA-Mn, n= 5, 10, 15, 20) with different contents of 5-(methacryloxy-2-ethoxyaminocarbonyl)methyl-thiazole (MEMT) were successfully synthesized, and SA-M20 was used to prepare a water-based antibacterial coating (PSA-M20). The structures of the films (SA-Mn-F) obtained from SA-Mn were analyzed by Fourier-transform infrared spectrometry using the attenuated total reflectance model (FTIR-ATR). The effects of the MEMT content on the properties of the emulsions and related films were investigated in the aspects of particle size, thermal stability, pencil hardness, adhesive force grade, water resistance, and surface morphology. The results showed that all the emulsions or related films had acceptable properties. The antibacterial and antibacterial durability tests showed that films obtained from emulsions SA-M15, SA-M20, and the coating PSA-M20 had strong and durable antibacterial activity against E. coliand S. aureus.

Cationic waterborne polyurethanes (CWPUs) bring in hydrophilic component to molecular chain, which inevitably deteriorates its water-resistant ability. Here, we synthesized a series of branched chain cationic waterborne polyurethanes (i.e., CWPUs-Si) that had been modified using a novel star-branched polydimethylsiloxane (SB-PDMS) to improve their water-resistant performance. The effects of SB-PDMS content on the properties of the CWPUs-Si polymers (e.g., crystallinity, emulsion stability, mechanical performance, surface element enrichment, surface topography, water resistance), together with the performance of coatings prepared by cathodic electrodeposition, were determined. The results showed that the introduction of SB-PDMS increased phase separation and surface roughness induced by hydrogen bonding while the surface energy decreased, both of which improved water resistance. The polymers showed improved rigidity due to increased content of the hard segments and enhanced physical crosslinking. Except for an increase in pencil hardness, SB-PDMS had no effect on the films prepared by cathodic electrodeposition. The results from this study may provide a strategy to improve the water-resistant properties of CWPUs.

Aimed at increasing the hydrophobicity of cathodic electrodeposition (CED) coatings based on cationic waterborne polyurethanes (WPUs), a series of cationic WPUs with hydrophobic octadecyl side chains were successfully synthesized by introducing 1-monostearoyl-rac-glycerol as a diol chain extender. ATR-FTIR spectra and SEM images showed the degree of phase separation between soft segments and hard segments of cationic WPUs clearly increased by incorporating octadecyl groups. The water contact angle and water absorption studies showed that the water-resistance property of modified CED coatings was obviously enhanced because of the incorporation of a low surface energy unit and the formation of a more sophisticated surface induced by hydrogen bonds. The International Standardization test of paints and varnishes revealed that the CED films possessed excellent hardness, adhesion, flexibility, and impact resistance. Optical transmittance tests showed that the sample films possessed excellent optical transmittance of about 90%, and meanwhile, the thermostability of the film was promoted.

Objective Our aim was to test the hypothesis that electroacupuncture (EA) at acupuncture point LI4 activates specific brain regions by nerve stimulation that is mediatied through a pathway involving the brachial plexus.Methods Twelve acupuncture naive right-handed volunteers were allocated to receive three sessions of EA at LI4 in a random different order (crossover): (1) EA alone (EA); EA after injection of local anaesthetics into the deltoid muscle (EA+LA); and (3) EA after blockade of the brachial plexus (EA+NB). During each session, participants were imaged in a 3 T MRI scanner. Brain regions showing change in blood oxygen level-dependent (BOLD) signal (activation) were identified. Subjective acupuncture sensation was quantified after functional MRI scanning was completed. Results were compared between the three sessions for each individual, and averaged.Results Blockade of the brachial plexus inhibited acupuncture sensation during EA. EA and EA+LA activated the bilateral thalamus, basal ganglia, cerebellum and left putamen, whilst no significant activation was observed during EA+NB. The BOLD signal of the thalamus correlated significantly with acupuncture sensation score during EA.Conclusions Blockade of the brachial plexus completely abolishes patterns of brain activation induced by EA at LI4. The results suggest that EA activates specific brain regions through stimulation of the local nerves supplying the tissues at LI4, which transmit sensory information via the brachial plexus.Trial Registration Number ChiCTR-OO-13003389.

The methacrylate resin‐based sealers have attracted wide attention with easy handling, superior aesthetic qualities, good mechanical properties, and excellent adhesive ability with dentin. 2,2‐bis[4‐(2′‐hydroxy‐3′‐methacryloyloxypropoxy)phenyl]‐propane (Bis‐GMA) is the main component of a new developing commercial root canal sealer “Epiphany,” which is one of the methacrylate resin‐based sealers. To further reduce polymerization volume shrinkage of bis‐GMA, 9,9′‐bis[4‐(2′‐hydroxy‐3′‐methacryloyloxypropoxy)‐phenyl]fluorene (HMPF) with higher molecular weight and larger molecular volume was selected to replace bis‐GMA as one of the components of the root canal sealer in this study. Photopolymerization behavior of a mixture of HMPF and triethylene glycol dimethacrylate (TEGDMA) was investigated by FTIR spectroscopy. Degree of conversion, volume shrinkage, and water sorption of various HMPF/TEGDMA formulations were measured and compared with a 50:50 bis‐GMA/TEGDMA formulation. The results illustrated that, with increasing content of HMPF in HMPF/TEGDMA system, the double bond conversion of the cured resin increased and volume shrinkage decreased. Its water sorption increased with increasing content of HMPF when the content was less than 50% and decreased with an increase in HMPF when the content was more than 50%. Compared with bis‐GMA/TEGDMA system, HMPF/TEGDMA had lower double bond conversion, lower polymerization shrinkage, and higher water sorption. © 2009 Wiley Periodicals, Inc. Adv Polym Techn 27:108–116, 2008; Published online in Wiley InterScience (). DOI 10.1002/adv.20125