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The sequence effects on the conformations and intra-molecular hydrogen bonds (NH···OC: H-bond) of collagen-like co-peptides (single chains) were analyzed using co-glycine (G)/L-proline (P) oligopeptides (6- and 9-mer, G/P = 1/2 mol), by QCC [B3LYP/6-31G(d,p)], with homo-oligopeptides. Each sequence was specified using three kinds of basic triplets of GPP, PGP, and PPG. The conformations (dihedral angles: φn/ψn) varied depending on the sequences. The conformation types of each unit were classified in the following three groups: φ/ψ of g−/g + (shorter polyproline II helical structure: P-like) with H-bond, g−/t + (polyproline II helical structure: PPII) with no H-bond, and φ/ψ of t−/g + with no H-bond. All H-bonds that have seven-membered ring were formed between units separated by one peptide. The positions and number (Nh) of H-bonds varied depending on the sequences. The H-bonds between CO of proline and NH of glycine unit were newly formed. The co-peptides that have no GPP triplet in N-end side (CH3CO-GPP) were found to be more stable than the corresponding blend models due to the formations of newly formed H-bonds. From the comparison with the structures observed for triple helix of collagen in other works and the findings (the existence of the CO group that have no H-bond), it was inferred that collagen may be formed by conformational rearrangement from P-like (single chain) to PPII (triple helix) and may be stabilized by inter-molecular hydrogen bonding between the residual CO groups and water molecules.

This research is to investigate biology teachers’ stages of concerns about the Level 1 Biology Teacher Qualification Training Program and also to identify their perception, reflective thinking and intention of implementation about the subjects of this program. 39 biology teachers were participated in the survey using the Concerns Based Adoption Model (CBAM) journaling about the program. The results were as follows. First, biology teachers’ stages of concerns about the Level 1 Biology Teacher Qualification Training Program stayed at the low level in awareness concern, informational concern and personal concern, and showed very low level in management concern, consequence concern, collaboration concern and refocusing concern. Second, More than 90% biology teachers responded that they would implement 26 classes among total 29 classes in their school. They wanted concrete application examples that could be applicable to their classes, but showed a low level in collaboration concern. Biology teachers showed a high level of willingness to implement the subjects which could be highly available in class and have emerged as major interest, concrete examples that could be applied without correction or supplement. On the contrary, the willingness to implement courses requiring a high level of major was low. Therefore, it seems necessary to consider the characteristics of the participants for effective training. According to the survey, the participants have the need for core competencies and various teaching methods, but they have difficult in implementing them, therefore it is necessary develop the supplemental training program connected to actual class.

Ceramics have excellent properties such as hardness and thermal and chemical stability. Therefore, researchers have studied the use of 3D printing to produce complex shapes in tools and structural applications. The debinding and sintering processes for ceramic composite materials manufactured using digital light processing (DLP) 3D printing technology were studied. The slurry used for DLP 3D printing requires debinding and sintering, as it contains ceramics and binders. Therefore, the debinding and sintering processes were measured by TG-DSC curves, and the changes in material characteristics were evaluated by setting the debinding holding time (4, 5, and 6 h) and sintering temperature (1100, 1200, and 1300 °C) as parameters. After debinding for 6 h, the density of the ceramic sintered at 1300 °C was 1.36 g/cm2; the linear shrinkage was 22.1%/21.6%/28.5% along the x, y, and z axes, respectively; and the bending strength was 8.58 MPa. As a result of this study, we developed an optimized process for the debinding and sintering of ceramics manufactured through the DLP 3D printing process.

The structures and energies of anhydrate and hydrate (hydrate rate: h of 1) states of l-alanine (LA), glycine (G), l-proline (LP), and N-methyl glycine (MG) pentamers were calculated by quantum chemical calculation using B3LYP/6-31G(d,p), for four kinds of conformers (β-extended: φ/ψ = t−/t+, PPII: g−/t+, PPII-like: g−/g+, and α-helix: g−/g−). In LA and G, which have imino proton (NH), three conformation types of β-extended, PPII-like, and α-helix were obtained, and water molecules were mainly inserted between intra-molecular hydrogen bond of CO···HN in PPII-like and α-helix and attached to CO group in β-extended. In LA and G, PPII-like conformers were the most stable in the anhydrate and hydrate states, and the result for LA was different from some experimental and theoretical results reported by other works reporting that the main stable conformation of alanine oligopeptide was PPII. On the other hand, in LP and MG, which have no imino proton, two conformers (PPII and PPII-like) and three conformers (PPII, PPII-like, and α-helix) were obtained, respectively. PPII conformers were the most stable in the anhydrate and hydrate states, and the result for LP supported the reported experimental results that the main conformation of proline oligomer was PPII. It was found that the formation pattern and stability of conformation of oligopeptide were strongly dominated by the presence/absence of intra-molecular hydrogen bonding of CO···HN or the presence/absence of NH2 group in the starting amino acid.

Early detection of the zearalenone (ZEA) chemotype of Fusarium species could be a precautionary measure for preventing ZEA contamination in rice. In this study, a multiplex polymerase chain reaction (mPCR) assay for detecting ZEA-producing fungi in rice was established using a set of four primers targeting the ZEA biosynthesis genes PKS3, PKS13, ZEB1, and ZEB2. Two mPCR approaches were used: one that amplified the DNA obtained from Fusarium isolates (conventional method) and another that directly amplified the target DNA from rice samples without time-consuming DNA isolation (direct method). The two mPCR methods showed high sensitivity in detecting ZEA-producing species, with a detection limit of 1.25 pg/μL of genomic DNA and 102 and 103 spores/g of white and brown rice, respectively. Both methods were specific for ZEA-producing species and gave four band patterns. The application of the two mPCR methods to 51 Fusarium isolates and 41 rice samples revealed that 31% (16 of 51) and 24% (10 of 41) of the samples were contaminated with ZEA-producing species, respectively. The mPCR results were further evaluated using high-performance liquid chromatography; in general, the two methods yielded similar results. These findings indicate that both mPCR methods are suitable for the detection of ZEA-producing Fusarium species in white and brown rice; however, the direct method yielded more rapid results.

The research aimed to explore characteristics of individual behaviors as motivation, task commitment, and leadership exhibited by science gifted students at enrichment program in science gifted education center. Results showed that motivation was highest at introduction stage, but decreased as lessons progressed. Task commitment and leadership tended to increase from planning and conducting stages. Leadership was highest at discussion stage. Each student exhibited different sequences of behavioral characteristics along lesson stages. It was called for planning individually differentiated instructional strategies. Keywords: individual behavioral characteristics, science gifted students, student leadership, task commitment.

The structure and association energy of hydrated l-alanine pentamers at the hydration rate (h) of 0–1 were calculated by quantum chemical calculation (QCC) using the density functional theory [B3LYP/6-31G(d, p)] method for three kinds of stable conformers (β-extended: t−/t+, PPII-like: g−/g+, α-helix: g−/g−) converged by convergent calculations from l-alanine pentamers in gas phase. Water molecules are mainly inserted between intramolecular hydrogen bond of CO–HN in PPII-like and α-helix conformers and attached to the CO group in β-extended conformer. α-Helix conformer turns to PPII-like conformer at higher hydration rate. The association energy decreased with the increase of the hydration rate, indicating that the conformers were stabilized by the hydration. It was found that PPII-like conformer, which was the most stable in the anhydrate state, was also the most stable in the hydrate state. This structure corresponds to a middle structure of PPII (g−/t+) and β-extended (t−/t+) structures. These results obtained by energy calculation using QCC support the experimental results by Eker et al. and Graf et al., who reported that alanine oligomer exhibited a mixture of PPII and β-extended structure in aqueous solution.

Rice samples (n = 482) harvested for 2010–2012 in South Korea were analyzed for zearalenone content by high-performance liquid chromatography and fluorescence detection. The exposure of the Korean populations was assessed by a deterministic approach. Because the proportion of non-detectable results was >80% in white rice but less than

The conformational convergent calculations of alanine oligomer (2- to 7-mer) were performed by QCC in the order starting from 2-mer (4 × 164 kinds). The ϕ/ψ of 4- to 7-mer was converged to three types; α-helix (g+/g+ or g−/g−), PPII-like (g+/g− or g−/g+) and β-extended (t+/t− or t−/t+), in lower energy order. PPII-like was different from the PPII (g−/t+) reported, and considered to be 2.27 ribbon . The energy differences in left- and right-handed ‘methyl type’ of end group were found.

Conformational change during chain propagation of alanine oligomer was investigated by quantum chemical calculation(QCC) using 2∼5mers(×=2∼5) models. For estimation of the end group effects, two types of end group. “amide type”(CH3CONHand -CONHCH3) and “methyl type” (CH3NHand –CONHCH3), were prepared as both ends(N-and-C). Conformers optimized for 5-mer converged to three types of φ/Ψ : α-helix(g+/g+, or g-/g-), PPII-like(extended helix-like, g+/g-, or g-/g+), and β-extended (t+/t-, or t-/t+), in the order of lower energy, and the energies of leftand righthanded conformers were the same (5-mer. amide type ΔE= -1.05, right type ΔE= -1.62). Energies of the monomer unit(ΔE) of α-helix decreased with increases of monomer.

This paper is to review and study about the crystallization nucleating agent to improve the heat-resistance properties of poly(lactic acid). Four sub-micron sized nucleating agents, metallic salts of 2,2'-methylene bis(4,6-di-tert-butylphenol), were prepared and used as a crystallization nucleating agent. Thermal and mechanical properties of polymer compounds were investigated by DSC, HDT and UTM. As the results, While the heat-resistance properties of the polymer compound samples were increased linearly with the contents of nucleating agent as well as their smaller size. Among them, the highest heat-resistance property of compound was observed with 2 wt% of MPZ2. HDT values of PL98Z2 compound was 116℃ at 0.455Mpa.

Hole transport copolymers consisting of 3,4-ethylenedioxythiophene (EDOT) and N-4-butylphenyl-N,Ndiphenylamine (BTPA) were synthesized by oxidative coupling reaction using FeCl3 as an oxidant. These copolymers showed good solubility and their thin films showed sufficient morphological stability. The copolymers showed an absorption maximum around 320 nm. Copolymers had an oxidation peak at approximately 1.03∼1.14 V versus the Ag/AgCl electrode. The hole mobility increased with increasing portion of the EDOT unit. The hole mobility of the copolymer containing 57% of the EDOT unit showed the highest mobility of 3×10-5 cm2/V·s.

N-butyl-N,N-diphenylamine (BDPA) and N-4-butylphenyl-N,N-diphenylamine (BTPA) were polymerized by oxidation polymerization using iron (III) chloride as oxidant. BDPA showed higher polymerizability. Poly(BDPA) and poly(BTPA) showed UV absorption maximum at 362 and 373 nm. Oxidation potential of poly(BDPA) was 1.02 V versus Ag/AgCl, while that of poly(BTPA) was 1.12 V. Hole mobility of poly(BDPA) was 4.93 × 10−5 cm2/Vs and that of poly(BTPA) was 2.89 × 10−5 cm2/Vs at the electric field of 35 V/μm. The differences of the properties were explained by the higher electron donating power of alkyl group than phenyl group and conjugation of phenyl ring. It was found that both poly(BDPA) and poly(BTPA) can be used as hole transporting material for electroluminescent device.

Most speech recognition systems that have a large capacity and high recognition rates are isolated word speech recognition systems. In order to extend the scope of recognition, it is necessary to increase the number of words that are to be searched. However, it shows a problem that exhibits a decrease in the system performance according to the increase in the number of words. This paper defines the context information that affects speech recognition in a ubiquitous environment to solve such a problem and develops user localization method using inertial sensor and RFID. Also, we develop a new speech recognition system that demonstrates better performances than the existing system by establishing a word model domain of a speech recognition system by context information. This system shows operation without decrease of recognition rate in smart home environment.

Hole transport polymers consisting of 4-methoxytriphenylamine (P-MOTPA) and 4- n -butyltriphenylamine (P-BTPA) were synthesized by oxidative coupling reaction using FeCl 3 as an oxidant. These polymers had good solubility and their thin films showed sufficient morphological stability. 1 H NMR and 13 C NMR revealed that the monomers were exclusively connected at the p -positions of unsubstituted phenyl groups. Polymers had UV absorption maximum around 370 nm. Cyclic voltammograms of polymers showed well-defined pairs of reduction and oxidation peaks at 1.1 V versus Ag/AgCl, indicating that the polymers are electrochemically active. P-MOTPA and P-BTPA had hole drift mobility of being 4.04 × 10 −5 and 2.98 × 10 −5 cm 2 /V s at the electric field of 50 V/μm, respectively.

We report hole-induced ferromagnetism in diluted magnetic semiconductor Zn_(0.99)Mn_(0.01)O films grown on SiO₂/Si substrates by reactive sputtering. The p-type conduction with hole concentration over 10^(18) ㎝-³ is achieved by P doping followed by rapid thermal annealing at 800 ℃ in a N₂ atmosphere. The p-type Zn_(0.99)Mn_(0.01)O:P is carefully examined by x-ray diffraction and transmission electron microscopy. The magnetic measurements for p-Zn_(0.99)Mn_(0.01)O:P clearly reveal ferromagnetic characteristics with a Curie temperature above room temperature, whereas those for n-Zn_(0.99)Mn_(0.01)O:P show paramagnetic behavior. The anomalous Hall effect at room temperature is observed for the p-type film. This result strongly supports hole-induced room temperature ferromagnetism in p-Zn_(0.99)Mn_(0.01)O:P.

We have investigated the effects of Al codoping on the structural, electrical transport, and magnetic properties of oxide diluted magnetic semiconductor thin films prepared by reactive sputtering. Nondoped thin films show semiconducting transport behavior and weak ferromagnetic characteristic. The Al doping increases the carrier concentration and results in an decrease of resistivity and metal-insulator transition behavior. With increasing carrier concentration, the magnetic properties drastically change, exhibiting a remarkable increase of the saturation magnetization. These results show carrier-enhanced ferromagnetic order in Cr-doped ZnO.

We report the synthesis of spinel oxide ZnCo2O4 thin films and the effects of the oxygen partial pressure in the sputtering gas mixture on their electrical and magnetic properties. The conduction type and carrier concentration were found to be dependent on the oxygen partial pressure ratio: n-type and p-type for the oxygen partial pressure ratio below ∼70% and above ∼85%, respectively. A ferromagnetic coupling was observable in p-type ZnCo2O4, whereas an antiferromagnetic interaction was found for insulating and n-type ZnCo2O4 film, revealing hole-mediated ferromagnetic transition in ZnCo2O4. Arrott plot analysis of magnetization data at 5 K also indicated non-zero spontaneous magnetization for p-type ZnCo2O4. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

We report on the effect of the oxygen partial pressure ratio in the sputtering gas mixture on the electrical and magnetic properties of cubic spinel ZnCo2O4 thin films grown by reactive magnetron sputtering. The conduction type and carrier concentration in ZnCo2O4 films were found to be dependent on the oxygen partial pressure ratio. The maximum electron and hole concentration at 300 K were estimated to be as high as 1.37 × 1020 cm-3 and 2.81 × 1020 cm-3, respectively. While an antiferromagnetic coupling was found for n-type ZnCo2O4, a ferromagnetic interaction was observable in p-type ZnCo2O4, indicating hole-induced ferromagnetic transition in spinel ZnCo2O4.

We report on the growth of cubic spinel ZnCo2O4 thin films by reactive magnetron sputtering and bipolarity of their conduction type by tuning of oxygen partial pressure ratio in the sputtering gas mixture. Crystal structure of zinc cobalt oxide films sputtered in an oxygen partial pressure ratio of 90% was found to change from wurtzite Zn1−xCoxO to spinel ZnCo2O4 with an increase of the sputtering power ratio between the Co and Zn metal targets, DCo/DZn, from 0.1 to 2.2. For a fixed DCo/DZn of 2.0 yielding single-phase spinel ZnCo2O4 films, the conduction type was found to be dependent on the oxygen partial pressure ratio: n-type and p-type for the oxygen partial pressure ratio below ∼70% and above ∼85%, respectively. The electron and hole concentrations for the ZnCo2O4 films at 300 K were as high as 1.37×1020 and 2.81×1020 cm−3, respectively, with a mobility of more than 0.2 cm2/V s and a conductivity of more than 1.8 S cm−1.

We report on the growth of spinel ZnCo2O4 films using reactive magnetron sputtering and their electrical and magnetic properties, with particular emphasis on the relation of Curie–Weiss temperature (TCW) and conduction type. The conduction type and carrier concentration in these films were found to be dependent on the oxygen partial pressure ratio in the sputtering gas mixture. The highest electron and hole concentration at 300 K were 1.37×1020 and 2.81×1020 cm−3, respectively. A ferromagnetic coupling (TCW>0) was observable in p-type ZnCo2O4, whereas an antiferromagnetic interaction (TCW

In this work, the growth of Mn-doped p-type ZnO thin film by reactive sputtering and their conduction type dependent magnetic properties are reported. Mn-doped ZnO thin films are deposited on SiO/sub 2//Si substrates by reactive magnetron sputtering at 500/spl deg/C and P is used as p-type dopant in Mn-doped ZnO via ZnO target mixed with 10wt% P/sub 2/O/sub 5/. Rapid thermal annealing above 500/spl deg/C is also done. A p-type conduction with the highest concentration of 6.7 /spl times/ 10/sup 18/ cm/sup -3/ in Zn/sub 0.99/Mn/sub 0.01/O:P is accomplished by annealing at 800/spl deg/C under N/sub 2/ ambient. The p-type Zn/sub 0.99/Mn/sub 0.01/O:P film exhibits room temperature ferromagnetism with saturation magnetization of 0.301 emu/cm/sup 3/ and coercive field of 60 Oe in contrast with paramagnetism in n-type Zn/sub 0.99/Mn/sub 0.01/O:P. In addition, an anomalous Hall effect is observed at room temperature in p-type films. This result manifests the intrinsic nature of ferromagnetism, hole-induced ferromagnetism, in p-type Zn/sub 0.99/Mn/sub 0.01/O:P, and represents the possible realization of diluted magnetic semiconductor spintronic devices operable at room temperature.

We report the synthesis of cubic spinel thin films and the tunability of the conduction type by control of the oxygen partial pressure ratio. Zinc cobalt oxide films were grown on(200 nm)/Si substrates by reactive magnetron sputtering method using Zn and Co metal targets in a mixed Ar/atmosphere. We found from X-ray diffraction measurements that the crystal structure of the zinc cobalt oxide films grown under an oxygen-rich condition (the /Ar partial pressure ratio of 9/1) changes from wurtzite-type O to spinel-type with the increase of the Co/Zn sputtering ratio, . We noted that the above structural change accompanied by the variation of the majority electrical conduction type from n-type (electrons) to p-type (holes). For a fixed / of 2.0 yielding homogeneous spinel-type Ofilms, the type of the majority carriers also varied, depending on the/Ar partial pressure ratio: p-type for an -rich and n-type for an Ar-rich atmosphere. The maximum electron and hole concentrations for the Zn films were found to be 1.3710 c and 2.4110 c , respectively, with a mobility of about 0.2 /Vs and a high conductivity of about 1.8 Ω/ /.