Production and structural features of a water-soluble polysaccharide from a mutant strain of Agrobacterium sp.

We have developed a mutant strain derived from Agrobacterium sp. ATCC 31750, which produces a water-soluble polysaccharide having potential utility to the food, feed, pharmaceutical and cosmetic industries. A high concentration of product (15 g/L) is obtained by 48 h cultivation of the mutant strain under optimized fermentation conditions. The water-soluble polysaccharide obtained from cultures of the mutant strain beta82 has Glc:Man:Gal in approximate molar ratios of 5.8:6.7:1.0. The molecular weight of the polysaccharide was determined to be approximately 1000 kDa by HPSEC analysis. Linkage analysis contained 3-Glcp, 3-Manp, terminal Glcp and terminal Manp, as well as a small proportion of 3- and 3,4-Galp, and 4,6-Manp residues. Based on analyses using FT-IR and ¹³C NMR spectrometers, most glycosidic bonds joining these sugar residues are of the α-type, and acetyl groups are apparently attached to the polymer chain at random.     

An energy-efficient real-time scheduling scheme on dual-channel networks

The recent evolution of wireless sensor networks have yielded a demand to improve energy-efficient scheduling algorithms and energy-efficient medium access protocols. This paper proposes an energy-efficient real-time scheduling scheme that reduces power consumption and network errors on dual channel networks. The proposed scheme is based on a dynamic modulation scaling scheme which can scale the number of bits per symbol and a switching scheme which can swap the polling schedule between channels. Built on top of EDF scheduling policy, the proposed scheme enhances the power performance without violating the constraints of real-time streams. The simulation results show that the proposed scheme enhances fault-tolerance and reduces power consumption.     

DNA/Tannic Acid Hybrid Gel Exhibiting Biodegradability,Extensibility, Tissue Adhesiveness,and Hemostatic Ability

DNA has emerged as a novel material in many areas of materials science due to its programmability. Especially, DNA hydrogels have been studied to incorporate new functions into gels. To date, only a few methods have been developed for fabricating DNA hydrogels, such as the use of complementary sequences or covalent bond. Herein, it is demonstrated that one of the most well‐known plant‐derived polyphenols, tannic acid (TA), can form a DNA hydrogel which is named TNA hydrogel ( T A + D NA ). TA plays a role as a “molecular glue” by a new mode of action reversibly connecting between phosphodiester bonds, which is different from the crosslinking utilizing complementary sequences. TA intrinsically degrades due to ester bonds connecting between pyrogallol groups, causing a degradable DNA hydrogel. Furthermore, TNA gel is multifunctional in that the gel is extensible upon pulling and adhesive to tissues because of the rich polyphenol groups in TA (ten phenols per TA). Unexpectedly, TNA gel exhibits superior in vivo hemostatic ability that can be useful for biomedical applications. This new DNA hydrogel preparation method represents a new technique for fabricating a large amount of DNA‐based hemostatic hydrogel without chemically modifying DNA or requiring the crosslinking by complementary sequences.     

T-Cell-Mimicking Nanoparticles for Cancer Immunotherapy

Cancer immunotherapies, including adoptive T cell transfer and immune checkpoint blockades, have recently shown considerable success in cancer treatment. Nevertheless, transferred T cells often become exhausted because of the immunosuppressive tumor microenvironment. Immune checkpoint blockades, in contrast, can reinvigorate the exhausted T cells; however, the therapeutic efficacy is modest in 70–80% of patients. To address some of the challenges faced by the current cancer treatments, here T-cell-membrane-coated nanoparticles (TCMNPs) are developed for cancer immunotherapy. Similar to cytotoxic T cells, TCMNPs can be targeted at tumors via T-cell-membrane-originated proteins and kill cancer cells by releasing anticancer molecules and inducing Fas-ligand-mediated apoptosis. Unlike cytotoxic T cells, TCMNPs are resistant to immunosuppressive molecules (e.g., transforming growth factor-β1 (TGF-β1)) and programmed death-ligand 1 (PD-L1) of cancer cells by scavenging TGF-β1 and PD-L1. Indeed, TCMNPs exhibit higher therapeutic efficacy than an immune checkpoint blockade in melanoma treatment. Furthermore, the anti-tumoral actions of TCMNPs are also demonstrated in the treatment of lung cancer in an antigen-nonspecific manner. Taken together, TCMNPs have a potential to improve the current cancer immunotherapy.     

Effectiveness of filial therapy for Korean parents.

Explored the effectiveness of filial therapy in enhancing the parent–child relationship of Korean parents (aged 30–42 yrs) of kindergartners (aged 4–8 yrs). The experimental design of the study was a pretest–posttest, control group design in which all of the parents (32 Ss) completed 3 instruments, the Porter Parental Acceptance Scale, the Parenting Stress Index, and the Filial Problem Checklist. The parents were also videotaped playing with their child before and after the training as a means of measuring empathic behavior in parent–child interactions. Results of quantitative and qualitative analyses indicate that Korean parents can learn basic skills of play therapy and improve the relationship with their children. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Analysis of purge gas temperature in cyclic TSA process

This study analyzes the effect of an operating parameter on the dynamic behavior by performing dynamic simulations of cyclic thermal swing adsorption (TSA) system, in fixed beds packed with activated carbon as an adsorbent. This TSA process purifies and regenerates the ternary mixtures consisted of benzene, toluene and p-xylene. A mathematical model, considering the dynamic variation and spatial distribution of properties within the bed, has been formulated and described by a set of partial differential algebraic equations. The models are based on non-equilibrium, non-isothermal and non-adiabatic conditions. The breakthrough curves of our simulation model are compared with those of Yun's experiments (1999). The cyclic steady-state (CSS) cycles are obtained for the various cases by cyclic simulation. The influences of the purge gas temperature on breakthrough curves, CSS convergence time, cyclic operating step time, purge gas consumed, regeneration energy requirement and adsorption ability at CSS are also discussed.     

Alginate‐Boronic Acid: pH‐Triggered Bioinspired Glue for Hydrogel Assembly

The development of bioadhesives has become an emerging research field for tissue sealants, wound dressings, and hemostatic agents. However, assembling hydrogels using bioadhesive‐mediated attachment remains a challenging task. Significantly high water content (>90%) in hydrogels compared to that of biological tissues is the main cause of failure. Considering that hydrogels are primary testing scaffolds mimicking in vivo environments, developing strategies to assemble hydrogels that exhibit diverse properties is important. Self‐healing gels have been reported, but such gels often lack biocompatibility, and two gel pieces should be identical in chemistry for assembly, thus not allowing co‐existence of diverse biological environments. Herein, a mussel‐mimetic cis‐diol‐based adhesive, alginate‐boronic acid, that exhibits pH‐responsive curing from a viscoelastic solution to soft gels is developed. Associated mechanisms are that 1) polymeric diffusion occurs at interfaces utilizing intrinsic high water content; 2) the conjugated cis‐diols strongly interact/entangle with hydrogel chains; 3) curing processes begin by a slight increase in pH, resulting in robust attachment of diverse types of hydrogel building blocks for assembly. The findings obtained with alginate‐boronic acid glues suggest a rational design principle to attach diverse hydrogel building blocks to provide platforms mimicking in vivo environments.     

An Example‐based Approach to Synthesize Artistic Strokes using Graphs

In this paper, we propose a technique to produce artistic strokes in a variety of drawing material based on example images. Our approach is to divide example strokes scanned from images into small pieces along their stroke directions and synthesize a novel stroke by rearranging them along a user specified curve. The visible quality of a synthesized stroke can be maintained by utilizing the connectivity information stored in a directed graph constructed in the preprocessing step. At run‐time, the graph is traversed to find a path best matching the user specification given as a curve and additional information. The results of our experiments shows that visually convincing strokes of various materials can be generated efficiently.     

The upgrade of KSTAR timing system to support long-pulse operation and high-speed data acquisition

Since the first campaign of KSTAR in 2008, the home-made timing system had run for the synchronized operation of tokamak. The timing board which featured PMC-form factor, giga-bit optical communication, home-made protocol, multi-triggering capability, using GPS time and being integrated to EPICS (Experimental Physics and Industrial Control System), had advantages of compactness, modularity, platform independency and full functionality for the synchronized tokamak operation. However, there was deficiency in timing accuracy resulting from the engagement of software in realization of timing function and timing jitter due to poor isolation in output ports. Moreover, new requirements were on the rise as the plasma pulse length was getting longer and diagnostics operating at the higher frequency were newly installed.In order to meet new requirements and overcome the problems, the new timing board has been developed. As a result, the performance is remarkably enhanced: timing accuracy less than 5 ns, jitter less than 100 ps, 8 configurable multi-triggering sections, provision of maximum 100 MHz sampling clock. The KSTAR timing system upgraded by introducing the new timing board is participating in the 2011 campaign after calibration and consolidating the established timing system.This paper describes design, development and commissioning results of the new KSTAR timing system.     

TAPE: A Medical Adhesive Inspired by a Ubiquitous Compound in Plants

Adhesives play an important role in industrial fields such as electronics, architectures, energy plantation, and others. However, adhesives used for medical purpose are rather under‐developed compared with those used in industry and consumer products. One key property required for medical adhesives is to maintain their adhesiveness in the presence of body fluid. Here, an entirely new class of medical adhesives called TAPE is reported; this is produced by intermolecular hydrogen bonding between a well‐known polyphenol compound, tannic acid, and poly(ethylene glycol). The preparation method of TAPE is extremely easy, forming a few liters at once by just the simple mixing of the two compounds without any further chemical synthetic procedures. TAPE shows a 250% increase in adhesion strength compared with fibrin glue, and the adhesion is well maintained in aqueous environments. It is demonstrated that TAPE is an effective hemostatic material and a biodegradable patch for detecting gastroesophageal reflux disease in vivo. Widespread use of TAPE is anticipated in various medical and pharmaceutical applications such as muco‐adhesives, drug depots, and others, because of its scalability, adhesion, and facile preparation.