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Sulfonated poly(arylene ether sulfone) (SPAES) composite membranes were prepared using thermally-treated graphene oxide (GO) and poly(2,5-benzimidazole)-grafted graphene oxide (ABPBI-GO) as fillers for proton exchange membrane fuel cell (PEMFC) applications. Pristine graphene oxide was obtained from graphite by chemical oxidation, and 3,4-diaminobenzoic acid was then reacted with pristine graphene oxide to obtain ABPBI-GO. When GO and ABPBI-GO were incorporated into the SPAES matrix, the dimensional stability and mechanical strength of the membrane were improved. In particular, the SPAES/ABPBI-GO composite membranes exhibited improved dimensional stability, larger Young's modulus, and larger elongation at break than the SPAES/GO composite membranes due to the acid–base interaction between the sulfonic acid group of the SPAES matrix and the basic imidazole unit of ABPBI-GO. In addition, the SPAES/ABPBI-GO composite membranes possessed higher proton conductivity than pristine SPAES and SPAES/GO composite membranes because the acid–base interaction can generate additional proton conduction pathways in the membrane structures.

We report in-situ synthesis and direct deposition of Fe 2 O 3 nanoparticles (NPs) on the ionic liquid (IL)-functionalized carbon nanotubes (fCNT). As shown in transmission electron microscope (TEM) and scanning TEM (STEM) images, Fe 2 O 3 NPs with the diameter of 3–5 nm are randomly distributed on the sidewall of fCNT, revealing the nanocrystalline structure. The chemical identity and interaction of the fCNT/Fe 2 O 3 composite are investigated by FT-IR, Raman and XPS analyses. In particular, the fCNT/Fe 2 O 3 composite is solution-processable in a form of binder free and self-standing film. Such a free-standing electrode film based on the fCNT/Fe 2 O 3 composite achieve the discharge capacity of 413 mAh g −1 which is much greater than 34 mAh g −1 of the CNT and 191 mAh g −1 of the fCNT due to the redox reaction of Fe 2 O 3 NPs. Moreover, the fCNT/Fe 2 O 3 composite show the coulombic efficiency of 98% and the capacity fading from 272 mAh g −1 to 182 mAh g −1 after 50 cycles of charge/discharge.

Based on reversible photo crosslinkable properties, a series of polymethacrylate derivatives having cinnamoyl group in the side chain has been designed and synthesized. By simple UV irradiation and thermal treatment on these polymer films, a complete healing behavior accompanied by changes of the surface hardness was observed.

Here we report a nanohybrid of reduced graphene oxide (rGO) nanosheets at which monodispersed starburst carbon spheres (MSCSs) are intercalated for the use in high-performance supercapacitor electrodes. MSCSs that have large electrolyte ions-accessible surface area enlarge the interspacing between rGO nanosheets as a result of intercalation so that a hybrid electrode can increasingly form electrical double layers that store energy. Such electrode organization provides facilitated transport paths for both electron and ion. The volumetric capacitance of the hybrid electrode is 25 F cm−3 that is obtained at a constant current of 0.073 A cm−3, at least 2.5-fold greater than that of rGO electrode. The hybrid electrode also shows a good rate-retention capability of 81% as specific currents change from 0.073 to 1.5 A cm−3. The initial capacitance of the hybrid electrode remains unchanged, nearly 100% for at least 5000 charge/discharge cycles. The electrode also delivers high energy density, 1.7 × 10−3 Wh cm−3, and power density, 2.7 W cm−3.

Strong demand for high-performance energy-storage devices has currently motivated the development of emerging capacitive materials that can resolve their critical challenge (i.e., low energy density) and that are renewable and inexpensive energy-storage materials from both environmental and economic viewpoints. Herein, the pseudocapacitive behavior of lignin nanocrystals confined on reduced graphene oxides (RGOs) used for renewable energy-storage materials is demonstrated. The excellent capacitive characteristics of the renewable hybrid electrodes were achieved by synergizing the fast and reversible redox charge transfer of surface-confined quinone and the interplay with electron-conducting RGOs. Accordingly, pseudocapacitors with remarkable rate and cyclic performances (~96 % retention after 3000 cycles) showed a maximum capacitance of 432 F g(-1), which was close to the theoretical capacitance of 482 F g(-1) and sixfold higher than that of RGO (93 F g(-1)). The chemical strategy delineated herein paves the way to develop advanced renewable electrodes for energy-storage applications and understand the redox chemistry of electroactive biomaterials.

Graphene based electrical conductors are under consideration for numerous applications in energy storage, energy conversion devices, electronics and sensors. Here, we report a facile and versatile method for fabrication of graphene based composite microwires ranging from ∼20 to 250 μm in diameter via size reduction during dehydration of extruded larger diameter graphene oxide-loaded agarose hydrogel fibers. The graphene oxide is effectively reduced to graphene by chemical and thermal treatment. After dehydration and reduction, the resulting graphene composite microwires exhibit high electrical conductivities of up to 1.8 S m−1.

Submicron-thick films of composite (CSN) electrodes were prepared by the simple spin-coating of a multiwalled carbon nanotube (MWCNT) suspension with sucrose as the precursor to form a thin carbon layer; this was followed by heat treatment at 1000 °C for 2 h. Thin carbon layers were coated onto the outer surface of the MWCNTs and the resulting CSN electrode was shown to be an interconnected open network structure. This binder-free thin-film CSN electrode with a unique architecture has a large areal capacitance of ∼723 μF cm−2 at a constant current of 0.23 μA cm−2 in a Na2SO4 aqueous electrolyte. About 81% of the initial capacitance is preserved, even at high specific currents. Based on the results of electrochemical impedance spectroscopy, the CSN electrode was shown to concurrently optimize ion and electron transport for high power delivery. It also shows good cycle stability after prolonged operation (up to 3000 charge/discharge cycles).

For polymer electrolyte membrane fuel cell (PEMFC) applications at elevated temperature (>100 °C), a series of cross-linked benzoxazine–benzimidazole copolymer, P(HFa- co -BI), membranes are prepared by casting a solution of poly[2,2′-( m -phenylene)-5,5′-bibenzimidazole] (PBI) and di-functional benzoxazine monomer, 6,6′-(hexafluoroisopropylidene)bis(3-phenyl-3,4-dihydro-2 H -benzoxazine) (HFa), in N , N -dimethylacetamide prior to stepwise heating to 250 °C. The films are also viable to manufacture to large quantities and area by roll-to-roll coating. The resulting cross-linked copolymer, P(HFa- co -BI), membranes are found to be thermally and mechanically stable. Although the proton conductivity values of P(HFa- co -BI) membranes are smaller than that of the PBI membrane, their cell performance (0.68 V at 0.2 A cm −2 at 150 °C) is close to that of PBI membrane and their long-term durability ( ca . 3116 cycles on in situ accelerated lifetime mode of load cycling testing) is found to be far superior to the PBI membrane.

A series of organic/inorganic hybrid block and random copolymers were prepared by reversible addition–fragmentation chain transfer (RAFT) polymerization using poly(ethylene glycol) methyl ether methacrylate (PEGMA) and 3-(3,5,7,9,11,13,15-heptaisobutylpentacyclo[9.5.1.13,9.15,15.17,13]octasiloxane-1-yl)propyl methacrylate (MA-POSS) as monomers in order to study the effect of polymer morphology and POSS content on the properties of polymer electrolytes. Flexible and dimensionally stable free-standing films were made from the hybrid block and random copolymers mixed with lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) when the contents of MA-POSS unit were larger than 31 and 16 mol %, respectively. The ionic conductivity of the solid-state block copolymer (PBP) electrolyte was found to be 1 order of magnitude higher than that of the random copolymer (PRP) electrolyte when they had similar MA-POSS content, although their glass transition temperature values of their ion-conducting segments were quite clos...

Cross-linked copolymer membranes were prepared by casting poly[2,2′-(m-phenylene)-5,5′-bibenzimidazole] (PBI) solutions containing 6-fluoro-3-(pyridin-2-yl)-3,4-dihydro-2H-benzoxazine (pF) in N,N-dimethylacetamide, with subsequent step-wise heating to 220 °C. The phosphoric acid (PA) content, proton conductivity, and cell performance were found to increase with the increase in benzoxazine content in these membranes. The proton conductivities of the cross-linked copolymer membranes reached 0.09 S cm−1 at 150 °C under anhydrous conditions. Membrane-electrode assemblies (MEAs), prepared using the cross-linked copolymer membranes, showed larger operating voltage, 0.71 V at 0.2 A cm−2, than those from commercially available PBI membranes. Additionally, the MEAs were durable until 1,077 cycles, with slow lifetime loss rate, −0.14 mV h−1 on in situ accelerated lifetime mode (load cycling test).

Here we report new H3PO4-doped cross-linked benzoxazine–benzimidazole copolymer membranes showing high proton conductivity and long-term durability for use in proton-exchange membrane fuel cells at elevated temperatures (>100 °C). The cross-linked copolymer membranes were prepared by mixing of poly[2,2′-(m-phenylene)-5,5′-bibenzimidazole] (PBI) with 3-phenyl-3,4-dihydro-6-tert-butyl-2H-1,3-benzoxazine (pBUa) in N,N-dimethylacetamide, with subsequent stepwise heating to 220 °C, and even large-sized films (30 cm × 140 m) could be easily prepared. The membranes showed high proton conductivities of up to 0.12 S cm–1 at 150 °C under anhydrous conditions. Membrane–electrode assemblies (MEAs) employing the membranes showed operating voltages of 0.71 V at 0.2 A cm–2. Furthermore, the MEAs displayed long-term durability up to 1999 cycles, with much slower performance decay, −0.03 mV h–1, than those prepared using the PBI membrane in in situ accelerated lifetime mode (load cycling testing).

Cross-linked poly(2,5-benzimidazole) (C-ABPBI) membranes consisting of wholly aromatic groups were prepared by a reaction between three-arm poly(2,5-benzimidazole)s with three carboxylic acid end groups (T-ABPBI) and 3,3′-diaminobenzidine (DABI) in poly(phosphoric acid) (PPA) during the casting process. T-ABPBI was prepared by the polymerization of 3,4-diaminobenzoic acid and 1,3,5-benzenetricarboxylic acid in PPA, and the polymerization solution was directly used for the casting process. The cross-linking process improved the chemical stability of the host polymer, poly(2,5-benzimidazole) (ABPBI). The C-ABPBI membranes could contain a larger phosphoric acid (PA) content than the membranes of linear polybezimidazoles, such as ABPBI and poly[2,2′-(m-phenylene)-5,5′-bibenzimidazole]. Consequently, the C-ABPBI membranes showed higher proton conductivity values than the linear polymer membranes. For example, the C-ABPBI-50 membrane could contain a PA content >84 wt.% with a proton conductivity of 0.12 S cm−1 at 150 °C under anhydrous conditions.

Adipogenesis has been one of the most intensely studied models of cellular differentiation. During adipogenesis, differential expression of many adipogenesis related genes lead to profound changes in cellular, morphological, and physiological characteristics of the differentiating cells. The aim of the present study was to examine the expression levels of adipogenic candidate genes, cAMP early repressor (ICER), nephroblastoma over-expressed protein (NOV), heat shock protein beta 1 (HSPB1) and succinate dehydrogenase (SDH), during adipogenesis of bovine mesenchymal stem cells (BMSC). The BMSC were cultured in DMEM / low glucose medium with adipogenic inducers for 6 days and the expression of various candidate genes which seemed related to adipogenesis were measured by real-time PCR. This study showed that the expression of peroxisome proliferator activated receptor γ (PPARγ) and fatty acid binding protein 4 (FABP4) genes as adipogenic indicators were increased to 3.11 and 3.11 folds on day 6 than on day 0, respectively (p

PBI-LiHzS composite membranes were prepared by casting N,N'-DMAc solutions containing PBI and LiHzS, where the LiHzS contents in the membranes were between 2.5 and 10 wt.-%. LiHzS was obtained by reacting hydrazine sulfate and lithium carbonate in water. PBI-LiHzS composite membranes were thermally stable up to approximately 300 °C and their acid-absorbing capabilities were comparable to those of the pure PBI membranes. The proton conductivity of PBI-LiHzS composite membranes (2.12 × 10 -2 S · cm -1 at 180 °C and 0% RH) was higher than that of pure PBI membranes when used at the same acid doping levels. The mechanical stability of the composite membranes having less than 5 wt.-% of LiHzS was found to be close to that of pure PBI membranes.

The effect of autoclaving temperatures (100-120°C) on yields of enzyme-resistant starch (RS) from normal corn starch and the physicochemical properties of autoclaved-cooled starches were studied. The RS content increased linearly with increasing autoclaving temperature (R 2 = 0.993) and the number of autoclaving-cooling cycles at an autoclaving temperature of 120°C. The effect of the number of autoclaving-cooling cycles was more pronounced than that of temperature. The swollen starch weight measured at 60°C slightly increased as the RS content increased, and then drastically decreased with the continous increase of the RS content (R 2 = -0.969). As the RS content increased, all parameters of Rapid Visco Analyser (RVA) viscosity except breakdown decreased. Log RVA peak viscosity showed a negative correlation with the RS content (R 2 = -0.986). The enthalpy in the differential scanning calorimetry (DSC) endotherm corresponding to the transitions of RS linearly increased as the RS content increased (R 2 = 0.988). The RS content of the heat-treated starch estimated from the relationship between RS content and swollen starch weight at 60°C, log RVA peak viscosity or DSC enthalpy was in good agreement with that determined with the standard method.

A polybenzimidazole (PBI) containing bulky basic benzimidazole side groups, poly[2,2′-(2-benzimidazole-p-phenylene)-5,5′-bibenzimidazole] (BIpPBI), was prepared via the condensation polymerization of 3,3′-diaminobenzidine tetrahydrochloride dihydrate with 2-benzimidazole terephthalic acid in PPA. BIpPBI was found to be soluble in aprotic polar solvents without the addition of inorganic salts, such as lithium chloride, and the BIpPBI film also showed very good acid retention capability as well as very high proton conductivity. The maximum acid content of the BIpPBI film was approximately 81 wt.% and the proton conductivity value of the acid-doped BIpPBI membrane was 0.16 S cm−1 at 180 °C and a 0% relative humidity. For comparison, the maximum proton conductivity of the most commonly used polymer for the high-temperature fuel cell membrane, poly[2,2′-(m-phenylene)-5,5′-bibenzimidazole] (mPBI) membrane, is approximately 0.06 S·cm−1 at 180 °C under anhydrous conditions at a 65 wt.% acid content, which is the maximum acid content that a mPBI membrane can have.

A series of poly(aryl ether benzimidazole) copolymers bearing different aryl ether linkage contents were synthesized by condensation polymerization in polyphosphoric acid (PPA) by varying the feed ratio of 4,4′-dicarboxydiphenyl ether (DCPE) to terephthalic acid (TA). As the ether unit content in the copolymer increased, the solubility of the copolymer in PPA and N , N ′-dimethylacetamide/LiCl improved. For example 3–7 wt.% DMAc solution containing 2 wt.% of LiCl could be prepared from the copolymers. XRD studies revealed that the incorporation of flexible aryl ether linkages increased the chain d -spacings of the polymer backbones and decreased the crystallinity of the copolymers. Still, these copolymers having ether linkages showed reasonably good thermal/mechanical stability and high proton conductivity. For example, the copolymer with 30 mol% ether linkage had a tensile strength of 43 MPa (at 26 °C and 40% relative humidity) at an acid doping level of 7.5 mol H 3 PO 4 and a proton conductivity of 0.098 S cm −1 (at 180 °C and 0% relative humidity) at an acid doping level of 6.6 mol H 3 PO 4 .

Copolymers of poly(2,5-benzimidazole) (ABPBI) and poly[2,2'-(p -phenylene)-5,5'-bibenzimidazole] (pPBI) were synthesized for use as fuel cell membranes to take advantage of the properties of both constituents. The composition of the copolymers were controlled by changing the feed ratio of 3,4-diaminobenzoic acid and terephthalic acid with 3,3'-diaminobenzidine in the polycondensation reaction. The copolymer membranes showed higher conductivities, better mechanical properties, and larger acid absorbing abilities than commercial poly[2,2'-(m -phenylene)-5,5'-bibenzimidazole] membranes.

Marbling (intramuscular fat) is an important factor in determining meat quality in Korean beef market. A grain based finishing system for improving marbling leads to inefficient meat production due to an excessive fat production. Identification of intramuscular fat-specific gene might be achieved more targeted meat production through alternative genetic improvement program such as marker assisted selection (MAS). We carried out ddRT-PCR in 12 and 27 month old Hanwoo steers and detected 300 bp PCR product of the inducible cAMP early repressor (ICER) gene, showing highly gene expression in 27 months old. A 1.5 kb sequence was re-sequenced using primer designed base on the Hanwoo EST sequence. We then predicted the open reading frame (ORF) of ICER gene in ORF finder web program. Tissue distribution of ICER gene expression was analysed in eight Hanwoo tissue using realtime PCR analysis. The highest ICER gene expression showed in Small intestine followed by Longissimus dorsi. Interestingly, the ICER gene expressed 2.5 time higher in longissimus dorsi than in same muscle type, Rump. For gene expression analysis in high- and low marbled individuals, we selected 4 and 3 animal based on the muscle crude fat contents (high is 17-32%, low is 6-7% of crude fat contents). The ICER gene expression was analysed using ANOVA model. Marbling (muscle crude fat contents) was affected by ICER gene (P

Muscle fat content including intramuscular fat content(IMF) is the most important parameter in meat quality of cattle. Triacylglycerol is the major component of fat and is found in adipocyte and skeletal muscle. In present study, we carried out the determined of triacylglycerol contents and mRNA expression patterns of genes related with triacylglycerol biosynthesis such as ACSS2, GPAT, MGAT and DGAT in Hanwoo longissimus muscle using the real-time PCR. The triacylglycerol contents were continuously increased during the fattening stages. Interestingly, the contents of triacylglycerol were 7.4 fold higher(0.34 vs. 2.51, P

Here, we report composite membrane consisting of poly[2,2′-(m-phenylene)-5,5′-(bibenzimidazole)] (PBI) and polyhedral oligomeric silsesquioxane functionalized with phosphonic acid groups (PO(OH)2-POSS) for high temperature proton exchange membrane. ~7 phosphonic acid groups are incorporated into the phenyl rings of POSS via bromination in a high yield (~93%), followed by substitution of the bromine elements by phosphonate ester groupsviaa Pd(0) catalyzed P–C coupling reaction. Phosphonic acid groups are formed by the hydrolysis of the phosphonate ester groups in hydrobromic acid solution. At a 50 wt% of PA content in the membranes, PBI/PO(OH)2-POSS composite membrane shows larger proton conductivity of 3.2 × 10−3 S cm−1than 2.8 × 10−3 S cm−1of PBI membrane at 150°C and anhydrous conditions, owing to the multiple phosphonic acid groups of PO(OH)2-POSS that can function as proton transport medium at high temperature and low humidity conditions.

Irreducible knee dislocation due to incarcerated soft tissue structures in associated fractures is extremely uncommon. We report a case of irreducible, closed dislocation of the knee secondary to incarcerated patellar tendon in a Hoffa fracture (unicondylar fracture of femur in the coronal plane) with associated communited fracture of patella and disruption of both cruciates. We treated this case initially with open reduction and internal fixation of fracture and repair of the patellar tendon. During the total followup period of eighteen months, the patient had restricted joint range of motion with no joint instability despite aggressive physiotherapy and further surgical intervention. The prognosis of such complex knee injuries with combination of ligamentous injuries and associated fractures is much worse when compared to either injuries alone.

Marbling of cattle meat is dependent on the coordinated expression of multiple genes. Cattle dramatically increase their intramuscular fat content in the longissimus dorsi muscle between 12 and 27 months of age. We used the annealing control primer (ACP)-differential display RT-PCR method to identify differentially expressed genes (DEGs) that may participate in the development of intramuscular fat between early (12 months old) and late fattening stages (27 months old). Using 20 arbitrary ACP primers, we identified and sequenced 14 DEGs. BLAST searches revealed that expression of the MDH, PI4-K, ferritin, ICER, NID-2, WDNMI, telethonin, filamin, and desmin (DES) genes increased while that of GAPD, COP VII, ACTA1, CamK II, and nebulin decreased during the late fattening stage. The results of functional categorization using the Gene Ontology database for 14 known genes indicated that MDH, GAPD, and COP VII are involved in metabolic pathways such as glycolysis and the TCA cycle, whereas telethonin, filamin, nebulin, desmin, and ACTA1 contribute to the muscle contractile apparatus, and PI4-K, CamK II, and ICER have roles in signal transduction pathways regulated by growth factor or hormones. The final three genes, NID-2, WDNMI, and ferritin, are involved in iron transport and extracellular protein inhibition. The expression patterns were confirmed for seven genes (MDH, PI4-K, ferritin, ICER, nebulin, WDNMI, and telethonin) using real-time PCR. We found that the novel transcription repressor ICER gene was highly expressed in the late fattening stage and during bovine preadipocyte differentiation. This information may be helpful in selecting candidate genes that participate in intramuscular fat development in cattle.

We describe a novel double-bundle reconstruction method for ACL deficient knee. Grafts are tibialis allograft for AMB (anteromedial bundle) and semitendinosus autograft for PLB (posterolateral bundle). Femoral fixations are done by Bio-TransFix for AMB and EndoButton for PLB. Tibial fixations are done by Bio-interference screw for AMB at 60-70 degrees knee flexion and secure the PLB and remnant AMB graft simultaneously onto anteromedial aspect of tibia at 10-20 degrees knee flexion with spiked washer and screw. With our technique, graft lengths are not restricted and we provide strong femoral and tibial fixation if it is compared with previous techniques.

A bi-level damage detection algorithm that utilizes dynamic responses of the structure as input and neural network (NN) as a pattern classifier is presented. The signal anomaly index (SAI) is proposed to express the amount of changes in the shape of frequency response functions (FRFs) or strain frequency response function (SFRF). SAI is calculated by using the acceleration and dynamic strain responses acquired from intact and damaged states of the structure. In a bi-level damage identification algorithm, first the presence of damage is identified from the magnitude of the SAI value. Then the location of the damage is identified using the pattern recognition capability of the NN. The proposed algorithm is applied to an experimental model bridge to demonstrate the feasibility of the algorithm. Numerically simulated signals are used for training the NN, and experimentally acquired signals are used to test the NN. The results of this example application suggest that the SAI based pattern recognition approach may be applied to the structural health monitoring system for a real bridge.

We report a three-dimensional (3D) porous carbon electrode containing both nanoscale and microscale porosity, which has been hierarchically organized to provide efficient ion and electron transport. The electrode organization is provided via the colloidal self-assembly of monodisperse starburst carbon spheres (MSCSs). The periodic close-packing of the MSCSs provides continuous pores inside the 3D structure that facilitate ion and electron transport (electrode electrical conductivity ∼0.35 S m(-1)), and the internal meso- and micropores of the MSCS provide a good specific capacitance. The capacitance of the 3D-ordered porous MSCS electrode is ∼58 F g(-1) at 0.58 A g(-1), 48% larger than that of disordered MSCS electrode at the same rate. At 1 A g(-1) the capacitance of the ordered electrode is 57 F g(-1) (95% of the 0.24 A g(-1) value), which is 64% greater than the capacitance of the disordered electrode at the same rate. The ordered electrode preserves 95% of its initial capacitance after 4000 charging/discharging cycles.

Amylose and amylopectin are determinants of the physicochemical properties for starch and grain quality in rice. Their biosynthesis is catalyzed by the interplay of ADP-glucose pyrophosphorylase (AGPase), granule-bound starch synthase (GBSS), soluble starch synthase (SSS), a starch branching enzyme (SBE), and a starch debranching enzyme (SDE). In this study, the genes for these enzymes were highly expressed 7 to 28 days after flowering during grain development, and their expression closely matched increases in both starch content and grain weight Among all the tested cultivars, amylose contents in the rice grains remained essentially constant throughout their development The AGPase gene was highly expressed in the high-yield cultivars of both glutinous and non-glutinous rice. The SSS gene was actively expressed when mature GBSS mRNA decreased. Genes responsible for amylopectin biosynthesis were simultaneously expressed in the late stage of grain development. We have now demonstrated that the expression patterns of starch biosynthetic genes differ between glutinous and non-glutinous rice, and between Tongil (a Japonica/ Indica hybrid) and Japonica types.

Park, Y. S.*, S. K. Kim**, J. C. Lee**, S. I. Oh**, S. H. Lee*, B. K. Park*,J. I. Lee**, C. Y Lee** and C. G. Lee**Department of Companion and Laboratory Animal Science,College of Industrial Science, Kongju National University*,College of Veterinary Medicine, Chonnam National University**ABSTRACTThe trunk and limb of the Jindo, Korean native dog was measured in the present study. One hundredand ninety five Jindoes were randomly selected from the 1,985 dogs in the Jindo County in August 1998,which were screened by the judging committee of the County and registered by inserting electronic chipsin the withers. They were about a year and half old, and were white and fawn dogs. A total of 18 partsof the trunk and limb were measured using calipers and tapes. The average height at the withers was50.67 cm in dogs and 47.48 cm in bitches. The average body length was 52.99 cm in dogs and 50.33 cmin bitches. And the average height : body length ratio was 104.70 in dogs and 106.08 in bitches. Nodifferences were observed between the Jindoes of the two coat colors in these measurements. The resultsof this study would be useful for compiling the official standard for the adult Jindo.(Keywords : Jindo, Korean native dog, Trunk and limb measurements, 18 parts)

Some structural characteristics of hot-water soluble and insoluble starches (waxy black rice starch) were investigated. The hot-water soluble material content of waxy black rice starch was higher (16.6%) than that (13.4%) of Shinsunchalbyeo starch heated at 98 for 8 min. The Amax and absorbance at 625 nm for hot-water soluble and insoluble material of waxy black rice starch were lower than those of Shinsunchalbyeo. Elution patterns of hot water soluble and insoluble materials by gel permeation chromatography (Sepharose CL-2B) were similar in both samples.

This study was investigated to examine gelatinization properties of waxy black rice starches. X-ray diffraction patterns in raw starches showed traditional A type of cereals. The crystalline regions of both black rice and Shinsunchalbyeo starches disappeared when temperature increased to where the crystalline regions of two starches changed to amorphous ones. Scanning Electron Microscope showed that granule type of Shinsunchalbyeo starch was more collapsed compared to that of black rice starch heated at 6. Gelatinization in both samples completed when samples were heated at 63. The results by Differential Scanning Calorimetry (DSC) revealed that gelatinization patterns were similar in both samples. In Rapid Visco Analyzer examination, there was no difference in peak viscosity, breakdown, final viscosity and setback between Shinsunchalbyeo and waxy black rice starches.

Developments and applications of structural health monitoring (SHM) systems have become active particularily for long-span bridges in Korea. They are composed of sensors, data acquisition system, data transmission system, information processing, damage assessment, and information management. In this paper, current status of research and application activities on SHM systems for civil infra-structures in Korea are briefly introduced by 4 parts: (1) current status of bridge monitoring systems on existing and newly constructed bridges, (2) research and development activities on smart sensors such as optical fiber sensors and piezo-electric sensors, (3) structural damage detection methods using measured data, and (4) a test road project for verification and enhancement of the pavement design procedures by the Korea Highway Corporation. Finally the R&D activities of a newly established Smart Infra-Structure Technology Center at Korea Advanced Institute of Science and Technology are also briefly described.

This paper addresses signal processing and applicability of local damage detection algorithms on a 1/15 scale model of the Yeongjong Bridge floor system. As many as 48 channels of dynamic strain data were collected, corresponding to strain gauge placements on the in-situ structure. Model excitation was induced via a series of impact hammer strikes. Twelve different damage cases are examined including connection loosening, chord removal, saw-cuts on the deck plate, and bearing removal simulating hanger failure. Signal anomaly index (SAI) representing the amount of change in frequency response is adopted to detect the presence and type of damage along with a series of neural network classifiers. It is found that SAI and ANN are promising tools for detecting local damage in steel bridges.

This paper investigated the relationship between the annual variation of the algae population and the phys- icochemical properties of the water reservoired in the Gachang Dam in the hopes of serving as a guideline in the production of a clean water supply to regions of the city of Taegu. Summer thermal stratification was formed in the freshwater reservoired in the Gachang Dam and thus dissolved oxygen (DO) decreased according to the depth of the water. The pH of epilimnion was much higher than that of hypolimnion in summer because of the difference in the photosynthesis rate of algae. In July, at the beginning of the rainy season, the amount of total nitrogen (T-N) in the freshwater reached a maximum of 1.92 mg/L without an increase in the amount of total phosphorus (T-P). In August, the concentration of T-P in the freshwater increased steeply and reached 0.12 mg/L. Aulacoseira spp. (diatoms) were predominantly distributed in the freshwater throughout the year and Synedra and Asterionella (diatoms) predominantly populated in the spring. However, Anabaena and Microcystis (blue-green algae), which caused malodor and a bad taste, flourished predominantly in epilimnion in August when the temperature of the water at the surface region increased to the maximum and the concentration of T-P was sufficiently high.

Development of high energy and power density secondary batteries is of great fundamental and applied interest. Systems which provide high power, without a significant reduction in energy are important for next-generation hybrid and all-electric vehicles. Li-iodine cells have been considered promising because of fast electrochemical conversion of the iodine/triiodide redox pair. To date, there only a few reports on rechargeable Li-iodine cells, in-part because of the drawbacks of iodine. Iodine is highly soluble in aprotic electrolytes, leading to self-discharge due to shuttling. Li-iodine cells use Li metal as an anode, however, Li metal can form dendrites which lead to shorting during cycling. Iodine is volatile even at room temperature, leading to cell fabrication challenges. Finally, iodine based electrodes suffer from low electrical conductivity. Here, we present the fabrication of a reduced graphene oxide (rGO)/LiI composite cathode with a gravimetric energy density of around 270 mAh/g which addresses some of these problems and demonstrate its operation in a full cell. LiI was uniformly coated on rGO by a solution-based method directly forming a free standing electrode. The use of LiI enables use of lithium-free anodes such as graphite, silicon, and tin. Its high melting (469 °C) and boiling points (1171 °C) provide the better thermostability compared to iodine and enables the use of various high temperature synthesis methods. The rGO facilitates rapid electron transfer and suppresses the dissolution of active materials species during cycling. We observe stable cycling performance of rGO/LiI electrodes at both low and high current densities. Promisingly, the rGO/LiI electrodes show good rate performance and a small hysteresis at high c-rates.

Selective wetting-induced micro-electrode patterning is used to fabricate flexible micro-supercapacitors (mSCs). The resulting mSCs exhibit high performance, mechanical stability, stable cycle life, and hold great promise for facile integration into flexible devices requiring on-chip energy storage.

Background: There are many limitations in using the plate for fixation of lateral malleolar fractures of the ankle. Methods: This study prospectively reviewed 60 of 72 consecutive patients with an average follow up of 3.8 years who had Danis-Weber type B ankle fractures that were treated with one or two 3.5-mm cortical lag screws without plate fixation. Results: A stable anatomic reduction was obtained in 57 cases (95%). The average time to healing by radiograph was 3.1 months. There were two delayed unions and no nonunions. Joint space narrowing was found in one case. Clinical assessment was satisfactory in 56 of the patients (93%). Conclusion: Noncomminuted Danis-Weber Type B ankle fractures can be successfully treated without the risk of lateral plating, which includes cartilage damage caused by penetration of the ankle joint, increased periosteal dissection, and the risk of subsequent hardware removal

Ceramics were introduced in total hip arthroplasty to address the problems of friction and wear that were reported with metal on polyethylene articulations. This remarkable sliding characteristics and wettable material could limit wear debries generation and provide longer lifetime of the artificial hip. Extensive clinical study shows that alumina to alumina is the best used in young and active patients, while the classic metal on polyethylene couple remains the gold standard in the remaining population. Compared with metal, ceramic is weak in tension and brittle and fracture is well recognized problem.

We describe a patient with spontaneous multiple extensor tendon ruptures that were caused by a displaced fragment of the lunate in advanced Kienbock's disease. Complete excision of the lunate, limited carpal fusion, and extensor tendon reconstructions relieved the patient's symptom and restored function.

This article describes a modified suture technique designed for the vertical repair of the anterior horn of the meniscus after arthroscopic decompression of a large meniscal cyst. This procedure comprises of three steps: first, the meniscus was pierced vertically using a suture hook and a No. 0 PDS suture. Second, both ends of the No. 0 PDS on the femoral and tibial surfaces of the meniscus were pulled to the outside of the joint capsule using a spinal needle preloaded with suture material. Finally, a skin incision was made adjacent to the suture materials, and both ends were tied. We recommend this technique not only for the vertical repair of the anterior horn of the meniscus after decompression of large meniscal cyst, but also to repair a longitudinal tear of the meniscus.

Developments and applications of Structural Health Monitoring (SHM) systems have become active particularly for long-span bridges in Korea. They are composed of sensors, data acquisition system, data transmission system, information processing, damage assessment, and information management. In this paper, current status of research and application activities on SHM systems for civil infra-structures in Korea are briefly introduced in four parts: (1) current status of bridge monitoring systems on existing and newly constructed bridges, (2) research and development activities on smart sensors such as optical fiber sensors and piezo-electric sensors, (3) structural damage detection methods using measured data, and (4) a test road project for pavement design verification and enhancement by the Korea Highway Corporation. Finally R&D activities of a new engineering research center entitled Smart Infra-Structure Technology Center at Korea Advanced Institute of Science and Technology are also briefly described. Journal of Civil Engineering Research and Practice Vol.1(1) 2004: 1-12

The purpose of this study was to evaluate the usefulness of titanium clips in the repair of transected peripheral nerves. The results of neurorrhaphy using titanium clips (VCS) were compared with the conventional technique of neurorrhaphy using nylon sutures. Transected sciatic nerves in 15 New Zealand white rabbits were repaired with VCS clips on one side and interrupted 9-0 nylon sutures on the other. The average time required for neurorrhaphy using the clip closure was 8.7 +/- 2.6 min, and this was shorter than the suture closure, which took 14.9 +/- 3.6 min (P0.01). Electromyographic studies revealed no significant differences in amplitudes of compound motor action potentials in both groups. Also, the number and extent of myelinizations of regenerated axons were not significantly different in both methods of nerorrhaphies. These results demonstrate that microscopic neurorrhaphy using titanium clips is a potential alternative to conventional neurorrhaphy using sutures.

The purpose of this study was to determine the incidence, relationship with the ankle diastasis, and effect of treatment of the anterior tibiofibular ligament avulsion fracture (Wagstaffe fracture) combined with the Weber type B lateral malleolar fracture.This study reviewed 94 cases of ankle fractures treated with operative methods.There were 52 cases of Weber type B lateral malleolar fractures and 13 cases of Wagstaffe fractures combined with them (25%). Ankle diastases were diagnosed in 20 cases (38.5%) in all Weber type B fractures and 11 (84.6%) of the 13 Wagstaffe fractures.The Wagstaffe fracture can be a good diagnostic clue of ankle diastasis in Weber type B lateral malleolar fracture. The accurate reduction and fixation of the avulsed fragment is important for restoration of the stable distal tibiofibular joint and to prevent the chronic ankle joint pain caused by impingement of the avulsed fragment.