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Two types of non-aqueous ceramic-coated separators, based on Al 2 O 3 and Mg(OH) 2 , with extremely high thermal stability are prepared at a pilot scale. To investigate the factors determining the electrochemical and safety performance of the battery, the structure and properties of Al 2 O 3 and Mg(OH) 2 separators are characterized at the entire separator and coating-layer level using nanoindentation. Both separators exhibit almost 0% thermal shrinkage, even at 200 °C, and good electrolyte wettability. The mechanical properties of the coating layers, represented as indentation modulus and hardness, reveal that the Mg(OH) 2 separator is more flexible than Al 2 O 3 separator, which is brittle, and exhibits a trend of hardness strengthening with increasing penetration depth. These mechanical properties of the coating layer of separators dominantly affect nail penetration more than electrochemical performance. Electrochemical performance is affected more by the uniformity and electrochemical stability of the ceramic/binder coating layer. Indeed, Al 2 O 3 and Mg(OH) 2 cells show similar value of capacity retention of 78.6 and 77.8% after 1100 cycles, and internal resistance of 128.5 and 132.0%, respectively. Pouch cells equipped with Mg(OH) 2 separators do not show any events, evaluated as L3, while Al 2 O 3 separator-incorporated cells are evaluated as L6 during the nail penetration test. Image 1 • The non-aqueous Al 2 O 3 and Mg(OH) 2 CCSs are investigated. • Crosslinked ceramic-polyurethane/PVdF composite gives thermal stability at 200 °C. • The E r and H of ceramic coating layers are determined by nanoindentation. • Flexible but tough Mg(OH) 2 CCS improves safety performance in nail penetration. • The Al 2 O 3 and Mg(OH) 2 CCSs improve high-temperature electrochemical performance. [ABSTRACT FROM AUTHOR]

Poly (aspartic acid sodium salt) (PAspNa) was evaluated for its potential as a novel draw solute in forward osmosis (FO). The inherent advantages of PAspNa, such as good water solubility, high osmotic pressure, and nontoxicity, were first examined through a series of physicochemical analyses and atomic-scale molecular dynamics simulations. Then, lab-scale FO tests were performed to evaluate its suitability in practical processes. Compared to other conventional inorganic solutes, PAspNa showed comparable water flux but significantly lower reverse solute flux, demonstrating its suitability as a draw solute. Moreover, fouling experiments using synthetic wastewater as a feed solution demonstrated that PAspNa reversely flowed to the feed side reduced inorganic scaling on the membrane active layer. The recyclability of PAspNa was studied using both nanofiltration (NF) and membrane distillation (MD) processes, and the results exhibited its ease of recovery. This research reported the feasibility and applicability of FO-NF or FO-MD processes using PAspNa for wastewater reclamation and brackish water desalination. [ABSTRACT FROM AUTHOR]

Nonlinear guidance laws that consider impact time constraints are proposed. Two-dimensional and three-dimensional impact time control guidance laws are derived using Lyapunov stability theory. Under the consideration of the nonlinear kinematics, it is shown that the missile states converge to the desired equilibrium point by the Lyapunov stability theory. The singularity issue of the proposed guidance laws is also analyzed. Numerical simulations are performed to verify the performance of the proposed guidance laws. [ABSTRACT FROM AUTHOR]

The shape of self-assembling polymer-drug conjugates, influencing the cellular uptake, is one of the important factors to be considered for effective drug delivery. In this study, we described synthesis of polymeric drug conjugates of different morphologies with phytosphingosine (PHS) as a hydrophobic model drug and poly(amino acid) as a hydrophilic host polymer. By varying the amount of PHS grafted to poly(amino acid), PHS-poly(amino acid) conjugates exhibited morphological transition from spherical to worm-like micellar aggregates in the aqueous media. We investigated the physicochemical properties of self-assembled structures in terms of hydrodynamic size, surface charge, and critical aggregation concentration. The anticancer therapeutic potency of these self-assembled structures was also discussed in terms of cellular uptake and cytotoxicity of prodrug micelles as a function of dose and time by in vitro cell study. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 [ABSTRACT FROM AUTHOR]

Abstract: Biodegradable polymeric microneedles were developed as a method for achieving sustained transdermal drug release. These microneedles have potential as a patient-friendly substitute for conventional sustained release methods. However, they have limitations related to the difficulty of achieving separation of the needles into the skin. We demonstrated that microneedle separation into the skin was mediated by hydrogel swelling in response to contact with body fluid after the needles were inserted into the skin. The hydrogel microparticles were synthesized by an emulsification method using poly-N-isopropylacrylamide (PNIPAAm). The microneedles were fabricated by micromolding poly-lactic-co-glycolic acid (PLGA) after filling the cavities of the mold with the hydrogel microparticles. The failure of microneedle tips caused by hydrogel swelling was studied in regard to contact with water, insertion of microneedles into porcine cadaver skin in vitro, stress–strain behavior, and insertion into the back skin of a hairless mouse in vivo. The drug delivery property of the hydrogel particles was investigated qualitatively by inserting polymer microneedles into porcine cadaver skin in vitro, and the sustained release property of PLGA microneedles containing hydrogel microparticles was studied quantitatively using the Franz cell model. The hydrogel particles absorbed water quickly, resulting in the cracking of the microneedles due to the difference in volume expansion between the needle matrix polymer and the hydrogel particles. The swollen particles caused the microneedles to totally breakdown, leaving the microneedle tips in the porcine cadaver skin in vitro and in the hairless mouse skin in vivo. Model drugs encapsulated in biodegradable polymer microneedles and hydrogel microparticles were successfully delivered by releasing microneedles into the skin. [Copyright &y& Elsevier]

Herein we propose control of polymerization kinetics to prevent inherent scattering problem of holographic photopolymer system that is caused by a phase separation between matrix and photopolymerized grating polymers. To elucidate this, in this letter, phase stability of the photopolymer system was studied with molecular dynamic simulation of Flory-Huggins theory and was investigated in the respect of polymerization kinetics. It was controlled with the variables of monomer conversion and degree of polymerization by varying both reaction time and rates. In addition, volume grating fixing effect of post ultraviolet treatment on photopolymer was examined. [ABSTRACT FROM AUTHOR]

• The new synthesis route of siloxane-based materials is presented. • The key factor of hardness and modulus of hard coating material is both Mw and PDI. • The hard coating layer is studied with nanoindentation analysis. • 2-step sol-gel synthesized hard coating improved surface hardness by 32 %. Flexible but still hard coating materials have been paid attention for applications in flexible electronic devices, as efforts to substitute glasses. However, there have been little approaches to find out control parameters determining their flexibility and hardness. Here, we present reaction-controlled polysilsesquioxane (PSQ) resins with improved flexibility and hardness. In this study, the effects of various reaction conditions on the molecular weight of the PSQ resins are investigated in terms of reaction time, and absence of byproducts, accompanying the analysis of mechanical properties of the corresponding films using nanoindentation. With the reaction-controlled PSQ resins by removing byproducts such as alcohols, the molecular weight could be increased up to 44 % compared to PSQ containing the byproducts. The surface hardness and modulus of hard coating films are also enhanced by 32 % and 13 % compared to that from original PSQ resin, respectively. Finally, we demonstrate folding reliability for 100 k bending cycles at various bending radii of 6 to 1 mm that shows improved warpage property with less irreversible deformation upon the folding test. [ABSTRACT FROM AUTHOR]

Scrophularia have traditionally been used as herbal medicines to treat neuritis, sore throats, and laryngitis. In particular, S. takesimensis, a Korean endemic species with restricted distribution on Ulleung Island, holds significant resource and genetic value. However, its pharmacological properties have not been thoroughly evaluated. Thus, we provide detailed morphological characteristics and genomic information for S. takesimensis in this study. Moreover, its pharmacological activity was evaluated in an ovalbumin-induced asthma rat model, using extracts of S. takesimensis roots (100 or 200 mg/kg). The distinguishing features of S. takesimensis from related species include the presence or absence of stem wings, leaf shape, and habitat. The chloroplast (cp) genome of this species is 152,420 bp long and exhibits a conserved quadripartite structure. A total of 114 genes were identified, which included 80 protein-coding genes, 30 transfer RNA (tRNA) genes, and 4 ribosomal RNA (rRNA) genes. The gene order, content, and orientation of the S. takesimensis cp genome was highly conserved and consistent with the general structure observed in S. buergeriana and S. ningpoensis cp genomes. Confirming the anti-inflammatory effects of S. takesimensis extract (STE) using an established mouse model of ovalbumin-induced asthma, we observed reduced asthmatic phenotypes, including inflammatory cell infiltration, mucus production, and suppression of T helper 2 (Th2) cell. Furthermore, STE treatment reduced Th2 cell activation and differentiation. This study underscores the medicinal value of S. takesimensis. The importance of preserving S. takesimensis was revealed and crucial insights were provided for further research on its utilization as a medicinal resource. [ABSTRACT FROM AUTHOR]

Scutellaria baicalensis Georgi and Raphanus Sativus Linne herbal mixture (SRE) is a Chinese herbal medicine. In this study, we aimed to evaluate the therapeutic efficacy of SRE as an active ingredient for 2,4-dinitrochlorobenzene (DNCB)-induced atopic dermatitis (AD) and to predict the underlying therapeutic mechanisms and involved pathways using network pharmacological analysis. Treatment with SRE accelerated the development of AD-like lesions, improving thickness and edema of the epidermis. Moreover, administering the SRE to AD-like mice suppressed immunoglobulin E and interleukin-4 cytokine and reduced T lymphocyte differentiation. In silico, network analysis was used to predict the exact genes, proteins, and pathways responsible for the therapeutic effect of the SRE against DNCB-induced AD. These results indicated that the SRE exerted protective effects on the DNCB-induced AD-like model by attenuating histopathological changes and suppressing the levels of inflammatory mediators. Therefore, the SRE can potentially be a new remedy for improving AD and other inflammatory diseases and predicting the intracellular signaling pathways and target genes involved. This therapeutic effect of the SRE on AD can be used to treat DNCB-induced AD and its associated symptoms. [ABSTRACT FROM AUTHOR]

Asthma is a pulmonary disease induced by the inhalation of aeroallergens and subsequent inappropriate immune responses. Camellia sinensis (L.) Kuntze has been evaluated as an effective antioxidant supplement produced from bioactive compounds, including flavonoids. In this study, we aimed to determine the effects of Camellia sinensis (L.) Kuntze extract (CE) on ovalbumin-induced allergic asthma. The components of CE were analyzed using high-performance liquid chromatography (HPLC) chromatogram patterns, and asthmatic animal models were induced via ovalbumin treatment. The antioxidant and anti-inflammatory effects of CE were evaluated using 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH), 2,2′-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS), and nitric oxide (NO) assays. Seven compounds were detected in the CE chromatogram. In the ovalbumin-induced mouse model, CE treatment significantly decreased the inflammation index in the lung tissue. CE also significantly decreased eosinophilia and the production of inflammatory cytokines and OVA-specific IgE in animals with asthma. Collectively, our results indicate that CE has anti-inflammatory and antioxidant activities, and that CE treatment suppresses asthmatic progression, including mucin accumulation, inflammation, and OVA-specific IgE production. [ABSTRACT FROM AUTHOR]

Although there are several types of radiation exposure, it is debated whether low-dose-rate (LDR) irradiation (IR) affects the body. Since the small intestine is a radiation-sensitive organ, the present study aimed to evaluate how it changes when exposed to LDR IR and identify the genes sensitive to these doses. After undergoing LDR (6.0 mGy/h) γ radiation exposure, intestinal RNA from BALB/c mice was extracted 1 and 24 h later. Mouse whole genome microarrays were used to explore radiation-induced transcriptional alterations. Reverse transcription-quantitative (RT-q) PCR was used to examine time- and dose-dependent radiation responses. The histopathological status of the jejunum in the radiated mouse was not changed by 10 mGy of LDR IR; however, 23 genes were upregulated in response to LDR IR of the jejunum in mice after 1 and 24 h of exposure. Upregulated genes were selected to validate the results of the RNA sequencing analysis for RT-qPCR detection and results showed that only Na+/K+ transporting subunit α4, glucose-6-phosphatase catalytic subunit 2 (G6PC2), mucin 6 (MUC6) and transient receptor potential cation channel subfamily V member 6 levels significantly increased after 24 h of LDR IR. Furthermore, G6PC2 and MUC6 were notable genes induced by LDR IR exposure according to protein expression via western blot analysis. The mRNA levels of G6PC2 and MUC6 were significantly elevated within 24 h under three conditions: i) Exposure to LDR IR, ii) repeated exposure to LDR IR and iii) exposure to LDR IR in the presence of inflammatory bowel disease. These results could contribute to an improved understanding of immediate radiation reactions and biomarker development to identify radiation-susceptible individuals before histopathological changes become noticeable. However, further investigation into the specific mechanisms involving G6PC2 and MUC6 is required to accomplish this. [ABSTRACT FROM AUTHOR]

Theuse of forward osmosis (FO) process for seawater desalinationhas attracted tremendous interest in recent years. Besides the manufactureof suitable membranes, the major technical challenge in the efficientdeployment of the FO technology lies in the development of a suitable“draw solute”. Owing to its inherent advantages, poly(asparticacid) has arisen to be an attractive candidate for this purpose. However,an investigation of its molecular level properties has not been studiedin detail. In this paper, the dynamics of poly(aspartic acid) andits sodium salt in the dilute concentration regime have been reported.The quantification of the polymer conformational properties, its solvationbehavior, and the counterion dynamics are studied. The neutral polymershows a preferentially coiled structure whereas the fully ionizedpolymer has an extended structure. Upon comparing with poly(acrylicacid) polymer, another polymer which has been used as a draw solute,poly(aspartic acid) forms more number of hydrogen bonds as well asfewer ion pairs. [ABSTRACT FROM AUTHOR]

Abstract: Water soluble and biocompatible iron oxide nanoparticles coated with poly(aspartic acid) (PAsp), poly(asparagines) (PAsn), poly(2-hydroxy-ethyl l-aspartamide) (PHEA), and poly-α,β-(N-2-dimethylaminoethyl l-aspartamide) (PDMAEA) were prepared by hydrophobic interaction between hydrophobic iron oxide nanoparticles and each amphiphilic poly(amino acid)s graft polymer. The octadecyl side chain grafted poly(succinimide)(PSI-g-C18), used as a precursor polymer, was easily aminolyzed with nucleophilic compounds to form various poly(amino acid)s graft polymer (PAsp-g-C18, PAsn-g-C18, PHEA-g-C18, PDMAEA-g-C18,) and simultaneously stabilize the dispersion of iron oxide nanoparticles in aqueous solution. The diameters of the poly(amino acid)s coated iron oxide nanoparticles (PAIONs) were smaller than 30nm in aqueous solution, extremely stable in aqueous solutions with a wide range of pH and salt concentrations. Further, all the PAIONs showed excellent MR signal intensities (high r 2 values) and the cellular uptake property of the PAIONs was also evaluated. [Copyright &y& Elsevier]