27,456 research outputs found
Concentration in Knowledge Output: A case of Economics Journals
No full textThis paper assesses the degree of author concentration in seven economics journals, which were published in India during 1990-2002. To measure the degree of author concentration, Lotka's Law was used. Moreover, we also make an exploratory analysis of the geographic, economics subfield and institutional concentration in 704 economics journals. An important finding of this paper is that specialized journals in the sample report the highest degree of author concentration. This result is quite similar to the findings by Cox and Chung (1991). Furthermore, there are several instances showing that the journals lean towards certain norms; this may affect the flow of innovative ideas into economics. We conclude that a knowledge activity, involving the high degree of concentration and a biased publication process, may affect the flow of new ideas into the discipline.Concentration, Lotka's Law
Fission yeast dihydrolipoamide dehydrogenase gene is involved in G(1)/S cell cycle progression
No full textUsing functional complementation with a Schizosaccharomyces pombe genomic library, we have isolated a clone complementing a G(1)/S phase progression defective mutant. The newly isolated temperature-sensitive mutant, cyj150, showed elongated morphology at a restrictive temperature of 36 degrees C and DNA content analysis of the mutant indicated a defect in cell cycle progression at the G(1)/S phase. Sequence analysis of the genomic and cDNA clones complementing this elongated phenotype at 36 degrees C show that it encodes a protein that has 50% amino acid identity with dihydrolipoamide dehydrogenase from Saccharomyces cerevisiae and garden pea. Alignment of the deduced amino acid sequence of S. pombe dihydrolipoamide dehydrogenase (dld1(+)) with glutathione reductase and mercuric reductase revealed extensive homologies throughout the primary sequence and protein structure, and contained amino acid sequences of the active site region conserved from prokaryote to higher eukaryote. Gene disruption and tetrad analysis showed that dld1(+) is an essential gene for cell viability. Northern analysis indicates that transcriptional expression of this gene is not fluctuated according to the cell cycle, However, it is certain that malfunction of this Dld1 protein blocks the progression of cell cycle from G(1) to S phase. The sequence of the dld1(+) gene is available in EMBL/GenBank under Accession Number L40360. (C) 1997 Elsevier Science B.V
G Protein Beta 2 Subunit Antisense Oligonucleotides Inhibit Cell Proliferation and Disorganize Microtubule and Mitotic Spindle Organization
No full textThe association of G protein beta2 subunit (G beta2) with mitotic spindles in various mammalian cells has been demonstrated previously. Recently, we have identified the association of G beta2 protein with microtubules (Wu et al., [1998] J. Cell. Biochem. 70: 552-562). In the present experiment we have demonstrated the possible functional role of G beta2 in microtubule and mitotic spindle organization in mammalian cells. When G beta2 antisense phosphorothioate oligonucleotides were transfected into mammalian cells, inhibition of cell proliferation with cell death after a 4- day treatment was observed. If the transfected cells were incubated for two days and their G beta2 and microtubules were examined by Western blotting and immunofluorescence localization, marked reduction of the G beta2 protein, fragmentation and disassembly of cytoplasmic microtubules, and disorganized mitotic spindles were found. We conclude that the G beta2 protein is closely associated with microtubule assembly and may play a potential role in the regulation of cell proliferation and microtubule and mitotic spindle organization in mammalian cells. J. Cell. Biochem. 83: 136-146, 2001. (C) 2001 Wiley-Liss, Inc
Age-depth profile from a 2.5D model of the Beyond EPICA ice core drill site at Little Dome C, Antarctica
No full textWe used a 2.5D inverse model constrained by radar horizons to find the age-depth profile at the European Beyond EPICA - Oldest Ice project drill site (BELDC; 75.29917 °S, 122.44516 °E) at Little Dome C (LDC), Antarctica. Further details on the model can be found in the associated publication: Chung et al. (2024; doi:10.5194/egusphere-2024-1650). The model constraints were derived from the LDC-VHF radar dataset (Chung et al. 2023; doi:10.5194/tc-17-3461-2023). The radar survey was conducted during the 2019-20 Antarctic field season in a collaboration between the University of Alabama (UA), the University of Copenhagen (CPH) and the Alfred Wegener Institute (AWI), using the Little Dome C-Very High Frequency radar system (LDC-VHF; Chung et al., 2023; doi:10.5194/tc-17-3461-2023).
The 2.5D model was applied to a flow line from Dome C to BELDC by Chung et al. (2024; doi:10.5194/egusphere-2024-1650). Here we present the resulting modelled age-depth profile at BELDC. We put the "maximum age" where the age density becomes > 20 ka/m - the threshold for which a paleoclimatic signal can reasonably be extracted. This occurs at 2452 m depth with an age of 1.12 Ma. However, we have chosen to include the entire modelled profile down to the "accreted ice" depth of 2485 m, in case that < 20 ka/m requirement proves to be too stringent. The depth of accreted ice is the deepest point where the model provides physically interpretable results (see Chung et al., 2024 for details)
Carex brevispicula Gi Heum Nam & G. Y. Chung 2020
No full textCarex brevispicula Gi Heum Nam & G.Y. Chung (2020: 396) Holotype: KOREA, Jeollabuk-do: Jinan-gun, Seongsu-myeon, Jwapo-ri, Punghyeollaengcheon, 13 May 2011, G. H. Nam Carex 201_1 (NIBRVP291950; Fig. 1 -26). Isotypes: KOREA, Jeollabuk-do: Jinan-gun, Seongsu-myeon, Jwapo-ri, Punghyeollaengcheon, 13 May 2011, G. H. Nam Carex 201_2 (NIBRVP 619368), Carex 201_3 (NIBRVP 619369). Paratypes: KOREA, Gangwon-do: Jeongseon-gun, Gohan-eup, Gohna-ri, Mt. Hambaeksan, 4 June 2013, G. H . Nam NGH13-196 (2 sheets, NIBRVP435122); Pyeongchang-gun, Jinbu-myeon, Dongsan-ri, Woljeongsa Temple, 2 June 2012, J. H . Kim Carex-Kim 130 (2 sheets, NIBRVP362158). Gyeongsangnam-do: Hamyang-gun, Macheon-myeon, Samjeong-ri, Mt. Jirisan, 6 June 2010, G. H . Nam & J. H. Do Carex 35 (4 sheets, NIBRVP291986); Miryang-si, Sannae-myeon, Samyang-ri, Mt. Gajisan, 7 May 2011, G. H . Nam Carex 173 (5 sheets, NIBRVP291922). Jeollanam-do: Boseong-gun, Mundeok-myeon, Juksan-ri, Mt. Cheongsengsan, 24 April 2010, J. H . Kim & Y. H. Cho Kim 110769 (NIBRVP353066); Gurye-gun, Sandong-myeon, Jwasa-ri, Mt. Jirisan, Nogodan, 6 June 2006, J. H . Kim KJH162 (NIBRVP274808), KJH163 (NIBRVP274809). Seoul: Nowon-gu, Sanggye-dong, Mt. Buramsan, 6 May 2014, C. S . Lee Leecs1354 (NIBRVP505672). Note: Previously, Jang et al. (2020) provided information on its holotype and isotypes, but at that time, the name C. brevispicula was not validly published. When Nam et al. (2020) validly published it, its paratypes as well as its holotype and isotypes were designated. Their information is provided here.Published as part of Jang, Hyun-Do, Hyun, Chang-Woo, Ryu, Seah & Lee, Sang-Jun, 2022, Type specimens of vascular plants in the herbarium of the National Institute of Biological Resources (II), pp. 229-243 in Phytotaxa 539 (3) on page 238, DOI: 10.11646/phytotaxa.539.3.2, http://zenodo.org/record/636408
Simulation and Early Exercise Problem: The Case of Options on Minimum or Maximum of Two Risky Assets
No full textDraft Genome Sequences of Bacillus subtilis Strain DKU_NT_01 Isolated from Traditional Korean Food Containing Soybean (Chung-gook-jang)
No full textABSTRACT
Here, we report the whole-genome sequence of
Bacillus subtilis
strain DKU_NT_01 isolated from traditional Korean food containing soybean (chung-gook-jang). The
de novo
genome of
Bacillus subtilis
strain DKU_NT_01 has one contig and G+C content of 55.4%, is 4,954,264 bp in length, and contains 5,011 coding sequences (CDSs).
</jats:p
Modelled age-depth profiles of two ice core drill sites on Little Dome C, Antarctica
No full textWe used a 1D numerical model constrained by radar horizons to find the age-depth profiles at two locations on Little Dome C (LDC), Antarctica - the European Beyond EPICA - Oldest Ice project drill site (BELDC; 75.29917 °S, 122.44516 °E) and the Australian Million Year Ice Core project drill site (MYIC; 75.34132 °S, 122.52059 °E). Further details on the model can be found in the associated publication (Chung et al., 2023; The Cryosphere). The model was constrained by two different sets of radar horizons. 1. The radar survey conducted over the Dome C region conducted by the British Antarctic Survey over the 2016-17 and 2017-18 Antarctic field seasons using the sledge-borne DEep LOoking Radio Echo Sounder (DELORES; Mulvaney et al., 2023). 2. The radar survey conducted during the 2019-20 Antarctic field season in a collaboration between the University of Alabama (UA), the University of Copenhagen (CPH) and the Alfred Wegener Institute (AWI), using the Little Dome C-Very High Frequency radar system (LDC-VHF; Chung et al., 2023; PANGAEA). Applying the 1D model to the two radar datasets at the two ice core location result in the four predicted age-depth profiles that we present here: BELDC_DELORES, BELDC_LDC-VHF, MYIC_DELORES and MYIC_LDC-VHF. The age-depth profiles, extend to the deepest point where modelled age density < 20 ka/m - the threshold for which a paleoclimatic signal can reasonably be extracted
Including the irregularities in the light-weight floor/ceiling model
No full textChung and Fox previously presented a mathematical/computational model giving good prediction of low-frequency vibration of light-weight timber based floor/ceiling structures (LTFS) made up of: upper plate, joist beams and ceiling. In that work the geometry of the structure was assumed known, and precise. Experimental data from mock-up LTFS validated that model. In this paper we present an augmentation of that model by including uncertainty in the placement and shape of the timber joists. We calculate the variability in vibration response in the low-frequency range by taking account of measurements of the bending and twisting of 301 timber beams. Although, the model was originally constructed for low-frequency vibration, its usefulness in the mid frequency range ( > 150Hz ) is discussed. Earlier results showed that the rigidity of the connection between the upper plate and joist beams plays an important role in predicting resonance frequencies and vibration levels. We further consider these connection conditions in the presence of uncertainty
FIGURE 1. Paraphlomis koreana S.C in A new species of Paraphlomis (Lamiaceae) from Korea: an additional genus to the Korean flora
No full textFIGURE 1. Paraphlomis koreana S.C.Ko et G.Y.Chung. A. Habit. B. Leaf (adaxial surface). C. Magnified adaxial leaf surface (multicellular and pellucid glandular trichomes). D. Stem (squared cross-section surface). E. Corolla. F. Open calyx (abaxial). G. Open corolla. H. Pistil. I. Nutlet. Drawn from the holotype G. Y. Chung and S. C. Ko 11060301 (HNHM).Published as part of Ko, Sung Chul, Lee, You-Mi, Son, Kyong-Sook Chung Dong Chan, Nam, Bo Mi & Chung, Gyu Young, 2014, A new species of Paraphlomis (Lamiaceae) from Korea: an additional genus to the Korean flora, pp. 51-54 in Phytotaxa 175 (1) on page 52, DOI: 10.11646/phytotaxa.175.1.6, http://zenodo.org/record/514367
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