1,796 research outputs found

    Charge density functional plus UU calculation of lacunar spinel GaM4_4Se8_8 (M = Nb, Mo, Ta, and W)

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    Charge density functional plus UU calculations are carried out to examine the validity of molecular JeffJ_\text{eff}=1/2 and 3/2 state in lacunar spinel GaM4_4X8_8 (M = Nb, Mo, Ta, and W). With LDA (spin-unpolarized local density approximation)+U+U, which has recently been suggested as the more desirable choice than LSDA (local spin density approximation)+U+U, we examine the band structure in comparison with the previous prediction based on the spin-polarized version of functional and with the prototypical JeffJ_\text{eff}=1/2 material Sr2_2IrO4_4. It is found that the previously suggested JeffJ_\text{eff}=1/2 and 3/2 band characters remain valid still in LDA+U+U calculations while the use of charge-only density causes some minor differences. Our result provides the further support for the novel molecular JeffJ_\text{eff} state in this series of materials, which can hopefully motivate the future exploration toward its verification and the further search for new functionalities

    Lack of germline mutation at codon 211 of the prion protein gene (PRNP) in Korean native cattle — Short communication

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    Bovine prion diseases are composed of two types of bovine spongiform encephalopathy (BSE), classical BSE and atypical BSE. Recent studies have identified one case of atypical BSE with an E211K mutation. E211K is homologous to the human E200K mutation, which is related to familial Creutzfeldt-Jakob disease (CJD), one of the familial forms of human prion diseases. To date, familial forms of prion diseases have not been reported in non-human animals. Because the familial forms of human prion diseases account for more than 10% of all human prion disease cases, the detection of the E211K mutation in healthy cattle is very important for verifying the role of this mutation as a familial form of BSE. To detect putative mutations related to familial BSE, specifically E211K in Korean native cattle (Hanwoo) and Korean dairy cattle (Holstein), we performed direct sequencing targeting codon 211 and the adjacent regions of the bovine prion protein (PRNP) gene in 384 Hanwoo and 152 Holstein cattle. We did not find the E211K mutation in any of the Korean cattle. Although we did not find the E211K mutation in Korean native cattle, E211K is a postulated mutation; therefore, further screening in other countries and larger samples is highly desirable

    The first report of prion-related protein gene (PRNT) polymorphisms in goat

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    Prion protein is encoded by the prion protein gene (PRNP). Polymorphisms of several members of the prion gene family have shown association with prion diseases in several species. Recent studies on a novel member of the prion gene family in rams have shown that prion-related protein gene (PRNT) has a linkage with codon 26 of prion-like protein (PRND). In a previous study, codon 26 polymorphism of PRND has shown connection with PRNP haplotype which is strongly associated with scrapie vulnerability. In addition, the genotype of a single nucleotide polymorphism (SNP) at codon 26 of PRND is related to fertilisation capacity. These findings necessitate studies on the SNP of PRNT gene which is connected with PRND. In goat, several polymorphism studies have been performed for PRNP, PRND, and shadow of prion protein gene (SPRN). However, polymorphism on PRNT has not been reported. Hence, the objective of this study was to determine the genotype and allelic distribution of SNPs of PRNT in 238 Korean native goats and compare PRNT DNA sequences between Korean native goats and several ruminant species. A total of five SNPs, including PRNT c.-114G > T, PRNT c.-58A > G in the upstream of PRNT gene, PRNT c.71C > T (p.Ala24Val) and PRNT c.102G > A in the open reading frame (ORF) and c.321C > T in the downstream of PRNT gene, were found in this study. All five SNPs of caprine PRNT gene in Korean native goat are in complete linkage disequilibrium (LD) with a D’ value of 1.0. Interestingly, comparative sequence analysis of the PRNT gene revealed five mismatches between DNA sequences of Korean native goats and those of goats deposited in the GenBank. Korean native black goats also showed 5 mismatches in PRNT ORF with cattle. To the best of our knowledge, this is the first genetic research of the PRNT gene in goat

    Development of a chicken interferon-induced transmembrane protein 3 (IFITM3)-specific monoclonal antibody using phage display

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    Interferon-induced transmembrane protein 3 (IFITM3) has potent antiviral activity against several viruses. Recent studies have reported that the chicken IFITM3 gene also plays a pivotal role in blocking viral replication, but these studies are considerably limited due to being conducted at the RNA level only. Thus, the development of a chicken IFITM3 protein-specific antibody is needed to validate the function of IFITM3 at the protein level. Epitope prediction was performed with the immune epitope database analysis resource (IEDB-AR) program. The epitope was validated by four in silico programs, Jped4, Clustal Omega, TMpred and SOSUI. Chicken IFITM3 protein-specific monoclonal antibodies were screened by enzyme-linked immunosorbent assay through affinity between recombinant IFITM3 protein and phage-displayed candidate antibodies. Validation of the reactivity of the chicken IFITM3 protein-specific antibody to chicken tissues was carried out using western blotting. We developed a chicken IFITM3 protein-specific monoclonal antibody using phage display. The reactivity of the antibody with peripheral chicken tissues was confirmed using western blotting. To the best of our knowledge, this was the first development of a chicken IFITM3 protein-specific monoclonal antibody using phage display

    First report of a novel polymorphism and genetic characteristics of the leporine prion protein (PRNP) gene

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    Transmissible spongiform encephalopathies (TSEs) have been reported in a broad spectrum of hosts. The genetic polymorphisms and characteristics of the prion protein (PRNP) gene have a vital impact on the development of TSEs. Notably, natural TSE infection cases have never been reported in rabbits, and genetic variations of the leporine PRNP gene have not been investigated to date. To identify leporine PRNP gene polymorphism, we performed amplicon sequencing in 203 rabbits. We report a novel single nucleotide polymorphism on the leporine PRNP gene. In addition, we performed a comparative analysis of amino acid sequences of prion protein (PrP) across several hosts using ClustalW2. Furthermore, we evaluated the effect of changes of unique leporine PrP amino acids with those conserved among various species using Swiss-Pdb Viewer. Interestingly, we found seven unique leporine amino acids, and the change of unique leporine amino acids with those conserved among other species, including S175N, Q221K, Q221R, A226Y, A230G, and A230S, was predicted to reduce hydrogen bonds in leporine PrP

    Korean Pre-service Teachers' Flipped Learning Experiences in a Teacher Education Program

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    This study explores Korean pre-service teachers' perceptions, attitudes, and satisfaction with flipped learning courses in a teacher education program. A mixed research method was used to collect the end-of-semester survey (n=62) and individual interview data (n=4). Guided by the four pillars of flipped learning (FL), study results are followed. First, Korean pre-service teachers believed that flipped learning format provided a flexible learning environment where pre-service teachers (PSTs) learn course materials in their own space. This result indicated that their learning happened without the limits of time and space. Second, pre-service teachers showed that their self-directed learning could be enhanced while watching pre-recorded videos before attending the class. Most PSTs agreed that their self-directed learning could be enhanced after participating in the flipped learning courses. Third, pre-service teachers evaluated that the FL course instructor was a professional educator who conveyed the intentional content effectively. Fourth, pre-service teachers were generally satisfied with the FL courses and were willing to take the FL courses again in the future

    Facile Synthesis of Porous Silicon Nanofibers by Magnesium Reduction for Application in Lithium Ion Batteries

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    We report a facile fabrication of porous silicon nanofibers by a simple three-stage procedure. Polymer/silicon precursor composite nanofibers are first fabricated by electrospinning, a water-based spinning dope, which undergoes subsequent heat treatment and then reduction using magnesium to be converted into porous silicon nanofibers. The porous silicon nanofibers are coated with a graphene by using a plasma-enhanced chemical vapor deposition for use as an anode material of lithium ion batteries. The porous silicon nanofibers can be mass-produced by a simple and solvent-free method, which uses an environmental-friendly polymer solution. The graphene-coated silicon nanofibers show an improved cycling performance of a capacity retention than the pure silicon nanofibers due to the suppression of the volume change and the increase of electric conductivity by the graphene.Korea Institute of Energy Technology Evaluation and Planning (Human Resources Development Program Grant 20144030200600
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