세관 양광주 방전에서 플라즈마 확산의 완전 해

김동준,정종문,김정현,황하청,정재윤,조윤희,임현교,구제환,최은하,조광섭,Jin, D.J.,Jeong, J.M.,Kim, J.H.,Hwang, H.C.,Chung, J.Y.,Cho, Y.H.,Lim, H.K.,Koo, J.H.,Choi, E.H.,Cho, G.S. 한국진공학회 2010 Applied Science and Convergence Technology Vol.19 No.1

관경이 수 mm인 세관 램프 내부에서 플라즈마의 확산을 조사하기 위하여 이극성(ambipolar) 확산방정식을 해하였다. 반경 방향의 확산에 의한 유리관 벽에서의 플라즈마 소멸 특성시간은 $\tau_r\;=\;(r_0/2.4)^2/D_a$로 주어진다. 반경 $r_0{\sim}1\;mm$이고 이극성 확산계수 $D_a{\sim}0.01\;m^2/s$ 이면, $\tau_r{\sim}17\;{\mu}s$이다. 이는 램프의 교류전원 구동에서 플라즈마를 유지하기 위한 구동 최소 주파수 ~30 kHz에 해당한다. 고전압이 인가되는 전극부에 발생한 고밀도의 플라즈마가 양광주로 확산되는 특성시간은 $\tau_z{\sim}0.1\;s$이다. 고밀도 플라즈마 경계에서의 시간에 대한 확산속도는 $t{\sim}10^{-6}\;s$일 때 $u_D{\sim}10^2\;m/s$이고, $t{\sim}10^{-3}\;s$이면 그 속도는 $u_D{\sim}1\;m/s$로 느려진다. 따라서 램프 길이 ~1 m에 대하여 전극부에서 생성된 고밀도 플라즈마가 양광주 전체로 확산되는 시간은 수 초가 걸린다. The ambipolar diffusion equation has been solved in a fine-tube lamp of a few mm in diameter. In the diffusion of radial direction, the plasma diffuses and vanishes away at the glass wall by recombination with the characteristic time of plasma loss is given by $\tau_r\;=\;(r_0/2.4)^2/D_a$. With the radius $r_0{\sim}1\;mm$ and the ambipolar diffusion coefficient $D_a{\sim}0.01\;m^2/s$, the vanishing time is calculated $\tau_r{\sim}10\;{\mu}s$ which corresponds to the least value of frequency 30 kHz for the sustaining the plasma in the operation of high voltage AC-power. In the diffusion of longitudinal z-direction, a high density plasma generated at the area of a high voltage electrode, diffuses into the positive column with the characteristic time $\tau_z{\sim}0.1\;s$. The plasma diffusion velocity at the boundary of high density plasma is $u_D{\sim}10^2\;m/s$ at the time $t{\sim}10^{-6}$ s and the diffusion velocity becomes slow as $u_D{\sim}1\;m/s$ at $t{\sim}10^{-3}\;s$. Therefore, for the long lamp of 1 m, it takes about several seconds for the high density plasma at the area of electrode to diffuse through the whole positive column space.

Experimental Pathogenesis of Pullorum Disease with the Local Isolate of Salmonella enterica serovar. enterica subspecies Pullorum in Pullets in Bangladesh

M. G. Haider,E. H. Chowdhury,M. A. H. N. A. Khan,M. T. Hossain,M. S. Rahman,송희종,M. M. Hossain 한국가금학회 2008 韓國家禽學會誌 Vol.35 No.4

The research work was carried out to study the pathogenesis covering the clinical signs, gross and histopathological lesions in different organs, and reisolation and identification of the organisms after experimental infection with the local isolate of Salmonella enterica serovar. enterica subspecies (S.) Pullorum at different time interval of the experiment during the period February 2006 to December 2006. One hundred pullets (seronegative to S. Pullorum of 12 weeks age were purchased and divided into 5 (A, B, C, D and E) groups and each group consisted of 20 birds. Four groups (A, B, C and D) were infected orally with a dose of 106 CFU, 107 CFU, 2 × 107 CFU, 108 CFU of S. Pullorum, respectively, and one group (E) was treated as uninfected control. The used methods were necropsy and histopathology, culture of bacteria, staining and biochemical test of Salmonella. Five birds from each group were randomly selected and sacrificed 1st week, 2nd, 3rd and 4th weeks of post infection (PI). From all the groups, the bacteriological samples (crop, liver, lung, heart, spleen, bile duodenum, ceca and blood) were collected with pre enriched in buffered peptone water in sterile poly bags. Liver, lungs, heart, spleen, intestine, etc. were collected in 10% buffered-formalin for histopathological examination. No clinical signs, gross and histopathological lesions were found in control group and no S. Pullorum was reisolated. Clinical sign of experimentally infected with S. Pullorum in pullets were loss of appetite (100%), slight depression (75%), ruffled feathers (85%), diarrhea (60%) and loss of weight (100%) in chickens. The feed intake and body weight at different weeks after PI differed significantly (p<0.01) among the groups. Grossly, the highest recorded lesion was button-like ulcer in the ceca (80%) and the lowest was white nodules in lungs (1.25%). S. Pullorum were reisolated from crop (91.25%), liver (91.25%), lung (83.75%), heart (71.25%), spleen (87.75%), bile (33.25%), duodenum (92.50%), ceca (97.50%) and from different group of infection (61.25%). The highest microscopic findings were intestinal and cecal mucosa and submucosa exhibited infiltration of mononuclear cells and congestion (96.25%), and the lowest finding was nodule formation in the lungs (3.75%). The pattern of the disease production by local isolate of S. Pullorum in Bangladesh is almost similar with other isolates in different countries. The research work was carried out to study the pathogenesis covering the clinical signs, gross and histopathological lesions in different organs, and reisolation and identification of the organisms after experimental infection with the local isolate of Salmonella enterica serovar. enterica subspecies (S.) Pullorum at different time interval of the experiment during the period February 2006 to December 2006. One hundred pullets (seronegative to S. Pullorum of 12 weeks age were purchased and divided into 5 (A, B, C, D and E) groups and each group consisted of 20 birds. Four groups (A, B, C and D) were infected orally with a dose of 106 CFU, 107 CFU, 2 × 107 CFU, 108 CFU of S. Pullorum, respectively, and one group (E) was treated as uninfected control. The used methods were necropsy and histopathology, culture of bacteria, staining and biochemical test of Salmonella. Five birds from each group were randomly selected and sacrificed 1st week, 2nd, 3rd and 4th weeks of post infection (PI). From all the groups, the bacteriological samples (crop, liver, lung, heart, spleen, bile duodenum, ceca and blood) were collected with pre enriched in buffered peptone water in sterile poly bags. Liver, lungs, heart, spleen, intestine, etc. were collected in 10% buffered-formalin for histopathological examination. No clinical signs, gross and histopathological lesions were found in control group and no S. Pullorum was reisolated. Clinical sign of experimentally infected with S. Pullorum in pullets were loss of appetite (100%), slight depression (75%), ruffled feathers (85%), diarrhea (60%) and loss of weight (100%) in chickens. The feed intake and body weight at different weeks after PI differed significantly (p<0.01) among the groups. Grossly, the highest recorded lesion was button-like ulcer in the ceca (80%) and the lowest was white nodules in lungs (1.25%). S. Pullorum were reisolated from crop (91.25%), liver (91.25%), lung (83.75%), heart (71.25%), spleen (87.75%), bile (33.25%), duodenum (92.50%), ceca (97.50%) and from different group of infection (61.25%). The highest microscopic findings were intestinal and cecal mucosa and submucosa exhibited infiltration of mononuclear cells and congestion (96.25%), and the lowest finding was nodule formation in the lungs (3.75%). The pattern of the disease production by local isolate of S. Pullorum in Bangladesh is almost similar with other isolates in different countries.

논문 : 생물생산시설 및 환경공학 ; 소규모 복도-더그매 예열 음압환기방식 무창자돈사의 최적 환기 요건에 관한 연구

이승주 ( S. J. Lee ),장동일 ( D. I. Chang ),황선호 ( S. H. Hwang ),( W. M. Gutierrez ),장홍희 ( H. H. Chang ) 한국농업기계학회 2010 바이오시스템공학 Vol.35 No.6

This study was carried out to determine necessary conditions for optimal ventilation of small windowless piglet house (4.0 (W) × 11.0 (L) × 2.6(H) m) with corridor and attic for preheating using CFD (Computational Fluid Dynamics) simulation. The experimental weaning piglet house was consisted of a corridor, an attic, 4 rooms (3.0 (W) × 2.75(L) m), 3 fences (0.7(H) m), 5 air inlets and 2 exhaust fans (0.4 (D) m) and simulated using CFD code, FLUENT. The simulation results for the experimental weaning piglet house showed that each room was uniformly ventilated under all the experimental conditions and air velocities at 0.1 m above floor are less than 0.15 m/s for 0.75 m/s and 1.0 m/s of air inlet velocity but 0.61 m/s for 1.25 m/s. The simulation results are similar to the measured results. Considering the air flow pattern, ventilating efficiency, air velocity at 0.1 m above floor and cold stress of weaning piglets and so on, the optimum velocity of air inlet might be 1.0 m/s.

Cosmic evolution of stellar quenching by AGN feedback: clues from the Horizon-AGN simulation

Beckmann, R. S.,Devriendt, J.,Slyz, A.,Peirani, S.,Richardson, M. L. A.,Dubois, Y.,Pichon, C.,Chisari, N. E.,Kaviraj, S.,Laigle, C.,Volonteri, M. Oxford University Press 2017 MONTHLY NOTICES- ROYAL ASTRONOMICAL SOCIETY Vol.472 No.1

<P>The observed massive end of the galaxy stellar mass function is steeper than its predicted dark matter halo counterpart in the standard Lambda cold dark matter paradigm. In this paper, we investigate the impact of active galactic nuclei (AGN) feedback on star formation in massive galaxies. We isolate the impact of AGN by comparing two simulations from the HORIZON suite, which are identical except that one also includes supermassive black holes (SMBHs) and related feedback models. This allows us to cross-identify individual galaxies between simulations and quantify the effect of AGN feedback on their properties, including stellar mass and gas outflows. We find that massive galaxies (M-* >= 10(11) M-circle dot) are quenched by AGN feedback to the extent that their stellar masses decrease by up to 80 per cent at z = 0. SMBHs affect their host halo through a combination of outflows that reduce their baryonic mass, particularly for galaxies in the mass range 10(9) M-circle dot <= M-* <= 10(11) M-circle dot, and a disruption of central gas inflows, which limits in situ star formation. As a result, net gas inflows on to massive galaxies, M-* >= 10(11) M-circle dot, drop by up to 70 per cent. We measure a redshift evolution in the stellar mass ratio of twin galaxies with and without AGN feedback, with galaxies of a given stellar mass showing stronger signs of quenching earlier on. This evolution is driven by a progressive flattening of the M-SMBH-M-* relation with redshift, particularly for galaxies with M-* <= 10(10) M-circle dot. M-SMBH/M-* ratios decrease over time, as falling average gas densities in galaxies curb SMBH growth.</P>

Sphingosine-1-phosphate-induced Flk-1 transactivation stimulates mouse embryonic stem cell proliferation through S1P₁/S1P₃-dependent β-arrestin/c-Src pathways

Ryu, J.M.,Baek, Y.B.,Shin, M.S.,Park, J.H.,Park, S.H.,Lee, J.H.,Han, H.J. Elsevier 2014 Stem cell research Vol.12 No.1

Although recent findings showed that the bioactive lipid metabolites can regulate the ES cell functions, the physiological relevance of interaction between sphingosine-1-phosphate (S1P) and Flk-1 and its related signaling molecules are not yet clear in ES cell proliferation. In the present study, S1P<SUB>1-5</SUB> receptors were expressed in mouse ES cells and S1P increased S1P<SUB>1-3</SUB> receptor expression level. S1P treatment stimulated the cellular proliferation in S1P<SUB>1/3</SUB>-dependent manner, located in lipid rafts. In response to S1P, β-arrestin was recruited to S1P<SUB>1/3</SUB> receptor and c-Src was activated. S1P also increased the binding of S1P<SUB>1/3</SUB> receptor with Flk-1. Similar to responses for VEGF, S1P increased Flk-1 phosphorylation, which was blocked by β-arrestin siRNA, and PP2, but not by VEGF-A<SUB>164</SUB> antibody or VEGF siRNA. In addition, S1P induced VEGF expression and VEGFR2 kinase inhibitor (SU1498) blocked the S1P-induced cellular proliferation. However, VEGF-A<SUB>164</SUB> antibody or VEGF siRNA partially blocked S1P-induced cellular proliferation, suggesting that both VEGF-dependent Flk-1 activation and VEGF-independent Flk-1 activation are involved in S1P-induced ES cell proliferation. S1P and VEGF-induced phosphorylation of ERK and JNK were blocked by pretreatment with SU1498. Moreover, inhibition of ERK and JNK blocked S1P-induced cellular proliferation. In conclusion, S1P-elicited transactivation of Flk-1 mediated by S1P<SUB>1/3</SUB>-dependent β-arrestin/c-Src pathways stimulated mouse ES cell proliferation.

Antibiotic susceptibility and resistance of Streptococcus iniae and Streptococcus parauberis isolated from olive flounder (Paralichthys olivaceus)

Park, Y.K.,Nho, S.W.,Shin, G.W.,Park, S.B.,Jang, H.B.,Cha, I.S.,Ha, M.A.,Kim, Y.R.,Dalvi, R.S.,Kang, B.J.,Jung, T.S. Elsevier Scientific Pub. Co 2009 Veterinary microbiology Vol.136 No.1

The rates of antibiotic susceptibility and resistance were investigated in Streptococcus iniae and Streptococcus parauberis isolates obtained from diseased olive flounders (Paralichthys olivaceus) collected from fish farms in Jeju Island, Korea. Isolates of S. iniae (n=65) were susceptible to cefotaxime, erythromycin, ofloxacin, penicillin, tetracycline and vancomycin, as demonstrated by the minimum inhibitory concentration (MIC) test. Isolates of S. parauberis (n=86) were highly resistant to erythromycin (58% of the 86 isolates tested) and tetracycline (63% of the 86 isolates tested). Fifty-four isolates of tetracycline-resistant S. parauberis contained the tet(M/O/S) genes, of which 39 and 12 isolates contained the tet(M) and tet(S) genes, respectively, whereas 3 isolates contained both the tet(M) and tet(S) genes. Among the erythromycin-resistant isolates of S. parauberis (n=50) only 14 contained the erm(B) gene. These results suggest that the tet(S) and erm(B) genes of S. parauberis are involved in the acquisition of high-level resistance to erythromycin and tetracycline. Our findings reveal a high rate of antibiotic resistance among strains of S. parauberis and emphasize the need to develop an appropriate vaccine to reduce the use of antibiotics.

GLOBULAR CLUSTER POPULATIONS: RESULTS INCLUDING S⁴G LATE-TYPE GALAXIES

Zaritsky, Dennis,McCabe, Kelsey,Aravena, Manuel,Athanassoula, E.,Bosma, Albert,Comeró,n, Sé,bastien,Courtois, Helene M.,Elmegreen, Bruce G.,Elmegreen, Debra M.,Erroz-Ferrer, Santiago,Gadot American Astronomical Society 2016 The Astrophysical journal Vol.818 No.1

<P>Using 3.6 and 4.5 mu m images of 73 late-type, edge-on galaxies from the S(4)G survey, we compare the richness of the globular cluster populations of these galaxies to those of early-type galaxies that we measured previously. In general, the galaxies presented here fill in the distribution for galaxies with lower stellar mass, M-*, specifically log(M-*/M-circle dot) < 10, overlap the results for early-type galaxies of similar masses, and, by doing so, strengthen the case for a dependence of the number of globular clusters per 10(9)M(circle dot) of galaxy stellar mass, T-N, on M-*. For 8.5 < log(M-*/M-circle dot) < 10.5 we find the relationship can be satisfactorily described as T-N = (M-*/10(6.7))(-0.56) M-* is expressed in solar masses. The functional form of the relationship is only weakly constrained, and extrapolation outside this range is not advised. Our late-type galaxies, in contrast to our early types, do not show the tendency for low-mass galaxies to split into two T-N families. Using these results and a galaxy stellar mass function from the literature, we calculate that, in a volume-limited, local universe sample, clusters are most likely to be found around fairly massive galaxies (M-* similar to 10(10.8)M(circle dot)) and present a fitting function for the volume number density of clusters as a function of parent-galaxy stellar mass. We find no correlation between T-N and large-scale environment, but we do find a tendency for galaxies of fixed M-* to have larger T-N if they have converted a larger proportion of their baryons into stars.</P>

Synthesis and Characterization of some Hippurato Rare Earth Metal Complexes

M.S. Refat*,S.M. Teleb,S.A. Sadeek,H.M. Khater,S.M. El-Megharbel 대한화학회 2005 대한화학회지 Vol.49 No.3

희토류 원소들은 마뇨산(HL)과, ML3·nH2O(M=La(III), n=4; M=Ce(III), n=7; M=Sm(III), n=8; HL= hippuric acid) 라는 일반식으로 표현될 수 있는 화합물들을 생성한다. 생성된 고체 화합물들의 특성이 원소분석, IR, 1H NMR, 전자 스펙트라, 그리고 열중량 분석을 통해 조사되었다. 리간드와 금속 이온들간의 배위 형태도 결정되었다.

S6K1 Phosphorylation of H2B Mediates EZH2 Trimethylation of H3: A Determinant of Early Adipogenesis

Yi, S.,Um, S.,Lee, J.,Yoo, J.,Bang, S.,Park, E.,Lee, M.,Nam, K.,Jeon, Y.,Park, J.,You, J.,Lee, S.J.,Bae, G.U.,Rhie, J.,Kozma, Sara C.,Thomas, G.,Han, J.W. Cell Press 2016 Molecular Cell Vol.62 No.3

S6K1 has been implicated in a number of key metabolic responses, which contribute to obesity. Critical among these is the control of a transcriptional program required for the commitment of mesenchymal stem cells to the adipocytic lineage. However, in contrast to its role in the cytosol, the functions and targets of nuclear S6K1 are unknown. Here, we show that adipogenic stimuli trigger nuclear translocation of S6K1, leading to H2BS36 phosphorylation and recruitment of EZH2 to H3, which mediates H3K27 trimethylation. This blocks Wnt gene expression, inducing the upregulation of PPARγ and Cebpa and driving increased adipogenesis. Consistent with this finding, white adipose tissue from S6K1-deficient mice exhibits no detectable H2BS36 phosphorylation or H3K27 trimethylation, whereas both responses are highly elevated in obese humans or in mice fed a high-fat diet. These findings define an S6K1-dependent mechanism in early adipogenesis, contributing to the promotion of obesity.

D_s⁺ meson production at central rapidity in proton-proton collisions at s=7 TeV

ALICE Collaboration,Abelev, B.,Adam, J.,Adamova, D.,Adare, A.M.,Aggarwal, M.M.,Aglieri Rinella, G.,Agocs, A.G.,Agostinelli, A.,Aguilar Salazar, S.,Ahammed, Z.,Ahmad, N.,Ahmad Masoodi, A.,Ahn, S.A.,Ahn North-Holland Pub. Co 2012 Physics letters: B Vol.718 No.2

The p<SUB>T</SUB>-differential inclusive production cross section of the prompt charm-strange meson D<SUB>s</SUB><SUP>+</SUP> in the rapidity range |y|<0.5 was measured in proton-proton collisions at s=7 TeV at the LHC using the ALICE detector. The analysis was performed on a data sample of 2.98x10<SUP>8</SUP> events collected with a minimum-bias trigger. The corresponding integrated luminosity is L<SUB>int</SUB>=4.8 nb<SUP>-1</SUP>. Reconstructing the decay D<SUB>s</SUB><SUP>+</SUP>→φπ<SUP>+</SUP>, with φ→K<SUP>-</SUP>K<SUP>+</SUP>, and its charge conjugate, about 480 D<SUB>s</SUB><SUP>+/-</SUP> mesons were counted, after selection cuts, in the transverse momentum range 2<p<SUB>T</SUB><12 GeV/c. The results are compared with predictions from models based on perturbative QCD. The ratios of the cross sections of four D meson species (namely D<SUP>0</SUP>, D<SUP>+</SUP>, D<SUP>@?+</SUP> and D<SUB>s</SUB><SUP>+</SUP>) were determined both as a function of p<SUB>T</SUB> and integrated over p<SUB>T</SUB> after extrapolating to full p<SUB>T</SUB> range, together with the strangeness suppression factor in charm fragmentation. The obtained values are found to be compatible within uncertainties with those measured by other experiments in e<SUP>+</SUP>e<SUP>-</SUP>, ep and pp interactions at various centre-of-mass energies.