Thermal and X-ray diffraction analysis studies during the decomposition of ammonium uranyl nitrate

Kim, B. H.,Lee, Y. B.,Prelas, M. A.,Ghosh, T. K. Springer Netherlands 2012 Journal of radioanalytical and nuclear chemistry Vol.292 No.3

<P>Two types of ammonium uranyl nitrate (NH<SUB>4</SUB>)<SUB>2</SUB>UO<SUB>2</SUB>(NO<SUB>3</SUB>)<SUB>4</SUB>·2H<SUB>2</SUB>O and NH<SUB>4</SUB>UO<SUB>2</SUB>(NO<SUB>3</SUB>)<SUB>3</SUB>, were thermally decomposed and reduced in a TG-DTA unit in nitrogen, air, and hydrogen atmospheres. Various intermediate phases produced by the thermal decomposition and reduction process were investigated by an X-ray diffraction analysis and a TG/DTA analysis. Both (NH<SUB>4</SUB>)<SUB>2</SUB>UO<SUB>2</SUB>(NO<SUB>3</SUB>)<SUB>4</SUB>·2H<SUB>2</SUB>O and NH<SUB>4</SUB>UO<SUB>2</SUB>(NO<SUB>3</SUB>)<SUB>3</SUB> decomposed to amorphous UO<SUB>3</SUB> regardless of the atmosphere used. The amorphous UO<SUB>3</SUB> from (NH<SUB>4</SUB>)<SUB>2</SUB>UO<SUB>2</SUB>(NO<SUB>3</SUB>)<SUB>4</SUB>·2H<SUB>2</SUB>O was crystallized to γ-UO<SUB>3</SUB> regardless of the atmosphere used without a change in weight. The amorphous UO<SUB>3</SUB> obtained from decomposition of NH<SUB>4</SUB>UO<SUB>2</SUB>(NO<SUB>3</SUB>)<SUB>3</SUB> was crystallized to α-UO<SUB>3</SUB> under a nitrogen and air atmosphere, and to β-UO<SUB>3</SUB> under a hydrogen atmosphere without a change in weight. Under each atmosphere, the reaction paths of (NH<SUB>4</SUB>)<SUB>2</SUB>UO<SUB>2</SUB>(NO<SUB>3</SUB>)<SUB>4</SUB>·2H<SUB>2</SUB>O and NH<SUB>4</SUB>UO<SUB>2</SUB>(NO<SUB>3</SUB>)<SUB>3</SUB> were as follows: under a nitrogen atmosphere: (NH<SUB>4</SUB>)<SUB>2</SUB>UO<SUB>2</SUB>(NO<SUB>3</SUB>)<SUB>4</SUB>·2H<SUB>2</SUB>O → (NH<SUB>4</SUB>)<SUB>2</SUB>UO<SUB>2</SUB>(NO<SUB>3</SUB>)<SUB>4</SUB>·H<SUB>2</SUB>O → (NH<SUB>4</SUB>)<SUB>2</SUB>UO<SUB>2</SUB>(NO<SUB>3</SUB>)<SUB>4</SUB> → NH<SUB>4</SUB>UO<SUB>2</SUB>(NO<SUB>3</SUB>)<SUB>3</SUB> → A-UO<SUB>3</SUB> → γ-UO<SUB>3</SUB> → U<SUB>3</SUB>O<SUB>8</SUB>, NH<SUB>4</SUB>UO<SUB>2</SUB>(NO<SUB>3</SUB>)<SUB>3</SUB> → A-UO<SUB>3</SUB> → α-UO<SUB>3</SUB> → U<SUB>3</SUB>O<SUB>8</SUB>; under an air atmosphere: (NH<SUB>4</SUB>)<SUB>2</SUB>UO<SUB>2</SUB>(NO<SUB>3</SUB>)<SUB>4</SUB>·2H<SUB>2</SUB>O → (NH<SUB>4</SUB>)<SUB>2</SUB>UO<SUB>2</SUB>(NO<SUB>3</SUB>)<SUB>4</SUB>·H<SUB>2</SUB>O → (NH<SUB>4</SUB>)<SUB>2</SUB>UO<SUB>2</SUB>(NO<SUB>3</SUB>)<SUB>4</SUB> → NH<SUB>4</SUB>UO<SUB>2</SUB>(NO<SUB>3</SUB>)<SUB>3</SUB> → A-UO<SUB>3</SUB> → γ-UO<SUB>3</SUB> → U<SUB>3</SUB>O<SUB>8</SUB>, NH<SUB>4</SUB>UO<SUB>2</SUB>(NO<SUB>3</SUB>)<SUB>3</SUB> → A-UO<SUB>3</SUB> → α-UO<SUB>3</SUB> → U<SUB>3</SUB>O<SUB>8</SUB>; and under a hydrogen atmosphere: (NH<SUB>4</SUB>)<SUB>2</SUB>UO<SUB>2</SUB>(NO<SUB>3</SUB>)<SUB>4</SUB>·2H<SUB>2</SUB>O → (NH<SUB>4</SUB>)<SUB>2</SUB>UO<SUB>2</SUB>(NO<SUB>3</SUB>)<SUB>4</SUB>·H<SUB>2</SUB>O → (NH<SUB>4</SUB>)<SUB>2</SUB>UO<SUB>2</SUB>(NO<SUB>3</SUB>)<SUB>4</SUB> → NH<SUB>4</SUB>UO<SUB>2</SUB>(NO<SUB>3</SUB>)<SUB>3</SUB> → A-UO<SUB>3</SUB> → γ-UO<SUB>3</SUB> → α-U<SUB>3</SUB>O<SUB>8</SUB> → UO<SUB>2</SUB>, NH<SUB>4</SUB> UO<SUB>2</SUB>(NO<SUB>3</SUB>)<SUB>3</SUB> → A-UO<SUB>3</SUB> → β-UO<SUB>3</SUB> → α-U<SUB>3</SUB>O<SUB>8</SUB> → UO<SUB>2</SUB>.</P>

Evaluation of the zoonotic potential of a novel reassortant H1N2 swine influenza virus with gene constellation derived from multiple viral sources

Lee, J.H.,Pascua, P.N.Q.,Decano, A.G.,Kim, S.M.,Park, S.J.,Kwon, H.I.,Kim, E.H.,Kim, Y.I.,Kim, H.,Kim, S.Y.,Song, M.S.,Jang, H.K.,Park, B.K.,Choi, Y.K. Elsevier Science 2015 INFECTION GENETICS AND EVOLUTION Vol.34 No.-

In 2011-2012, contemporary North American-like H3N2 swine influenza viruses (SIVs) possessing the 2009 pandemic H1N1 matrix gene (H3N2pM-like virus) were detected in domestic pigs of South Korea where H1N2 SIV strains are endemic. More recently, we isolated novel reassortant H1N2 SIVs bearing the Eurasian avian-like swine H1-like hemagglutinin and Korean swine H1N2-like neuraminidase in the internal gene backbone of the H3N2pM-like virus. In the present study, we clearly provide evidence on the genetic origins of the novel H1N2 SIVs virus through genetic and phylogenetic analyses. In vitro studies demonstrated that, in comparison with a pre-existing 2012 Korean H1N2 SIV [A/swine/Korea/CY03-1½012 (CY03-1½012)], the 2013 novel reassortant H1N2 isolate [A/swine/Korea/CY0423/2013 (CY0423-12/2013)] replicated more efficiently in differentiated primary human bronchial epithelial cells. The CY0423-12/2013 virus induced higher viral titers than the CY03-1½012 virus in the lungs and nasal turbinates of infected mice and nasal wash samples of ferrets. Moreover, the 2013 H1N2 reassortant, but not the intact 2012 H1N2 virus, was transmissible to naive contact ferrets via respiratory-droplets. Noting that the viral precursors have the ability to infect humans, our findings highlight the potential threat of a novel reassortant H1N2 SIV to public health and underscore the need to further strengthen influenza surveillance strategies worldwide, including swine populations.

Gut-Specific Delivery of T-Helper 17 Cells Reduces Obesity and Insulin Resistance in Mice

Hong, C.P.,Park, A.,Yang, B.G.,Yun, C.H.,Kwak, M.J.,Lee, G.W.,Kim, J.H.,Jang, M.S.,Lee, E.J.,Jeun, E.J.,You, G.,Kim, K.S.,Choi, Y.,Park, J.H.,Hwang, D.,Im, S.H.,Kim, J.F.,Kim, Y.K.,Seoh, J.Y.,Surh, C. Elsevier North Holland [etc.] 2017 Gastroenterology Vol.152 No.8

<P>BACKGROUND & AIMS: Obesity and metabolic syndrome have been associated with alterations to the intestinal microbiota. However, few studies examined the effects of obesity on the intestinal immune system. We investigated changes in subsets of intestinal CD4(+) T-helper (T-H) cells with obesity and the effects of gut-tropic T(H)17 cells in mice on a high-fat diet (HFD). METHODS: We isolated immune cells from small intestine and adipose tissue of C57BL/6 mice fed a normal chow diet or a HFD for 10 weeks and analyzed the cells by flow cytometry. Mice fed a vitamin A-deficient HFD were compared with mice fed a vitamin A-sufficient HFD. Obese RAG1-deficient mice were given injections of only regulatory T cells or a combination of regulatory T cells and T(H)17 cells (wild type or deficient in integrin beta 7 subunit or interleukin 17 [IL17]). Mice were examined for weight gain, fat mass, fatty liver, glucose tolerance, and insulin resistance. Fecal samples were collected before and after T cell transfer and analyzed for microbiota composition by metagenomic DNA sequencing and quantitative polymerase chain reaction. RESULTS: Mice placed on a HFD became obese, which affected the distribution of small intestinal CD4(+) T-H cells. Intestinal tissues from obese mice had significant reductions in the proportion of T(H)17 cells but increased proportion of T(H)1 cells, compared with intestinal tissues from nonobese mice. Depletion of vitamin A in obese mice further reduced the proportion of T(H)17 cells in small intestine; this reduction correlated with more weight gain and worsening of glucose intolerance and insulin resistance. Adoptive transfer of in vitro-differentiated gut-tropic T(H)17 cells to obese mice reduced these metabolic defects, which required the integrin beta 7 subunit and IL17. Delivery of T(H)17 cells to intestines of mice led to expansion of commensal microbes associated with leanness. CONCLUSIONS: In mice, intestinal T(H)17 cells contribute to development of a microbiota that maintains metabolic homeostasis, via IL17. Gut-homing T(H)17 cells might be used to reduce metabolic disorders in obese individuals.</P>

A study of γγ->K_S⁰K_S⁰ production at energies from 2.4 to 4.0 GeV at Belle

Belle Collaboration,Chen, W.T.,Abe, K.,Abe, K.,Adachi, I.,Aihara, H.,Anipko, D.,Aulchenko, V.,Bakich, A.M.,Barberio, E.,Bay, A.,Bedny, I.,Bitenc, U.,Bizjak, I.,Blyth, S.,Bondar, A.,Bozek, A.,Bracko, M North-Holland Pub. Co 2007 Physics letters: B Vol.651 No.1

K<SUB>S</SUB><SUP>0</SUP>K<SUB>S</SUB><SUP>0</SUP> production in two-photon collisions has been studied using a 397.6 fb<SUP>-1</SUP> data sample collected with the Belle detector at the KEKB e<SUP>+</SUP>e<SUP>-</SUP> collider. For the first time the cross sections are measured in the two-photon center-of-mass energy range between 2.4 GeV and 4.0 GeV and angular range |cosθ<SUP>*</SUP>|<0.6. Combining the results with measurements of γγ->K<SUP>+</SUP>K<SUP>-</SUP> from Belle, we observe that the cross section ratio σ(K<SUB>S</SUB><SUP>0</SUP>K<SUB>S</SUB><SUP>0</SUP>)/σ(K<SUP>+</SUP>K<SUP>-</SUP>) decreases from ∼0.13 to ∼0.01 with increasing energy. Signals for the χ<SUB>c0</SUB> and χ<SUB>c2</SUB> charmonium states are also observed.

On the zeolitic imidazolate framework-8 (ZIF-8) membrane for hydrogen separation from simulated biomass-derived syngas

Yin, H.,Lee, T.,Choi, J.,Yip, A.C.K. Elsevier 2016 Microporous and mesoporous materials Vol.233 No.-

<P>Hydrogen separation from biomass-derived syngas is a critical step in the utilization of gasification technology. Compared with the traditional methods, membrane technology provides an effective and low-cost solution for adjusting the gas composition and collecting H-2 in syngas environments. In this study, a zeolitic imidazolate framework-8 (ZIF-8)-based membrane, which is a potential candidate for H-2 separation from biomass-derived syngas, was successfully fabricated through the seeded (secondary) growth method and the subsequent post-treatments. The prepared ZIF-8 membrane exhibited a modest H-2 separation performance for H-2/CO2 and H-2/CO, with separation factors of 4.95 and 6.08, respectively, and a H-2 permeance of 7.81 x 10(-8) mol m(-2) s(-1) Pa-1 at 200 degrees C in the simulated biomass-derived syngas environments (H-2/CO2/CO) with the presence of steam. In particular, the H-2/CO2 and H-2/CO separation factors were increased by 36% and 97%, respectively, with respect to those obtained through bare supports. Despite the promising H2 perm-selectivity, the H-2/CO2 and H-2/CO separation factors of ZIF-8 membranes at 200 degrees C under water-containing syngas environments were maintained up to 10 h but the longer exposure led to the gradual degradation and eventual reduction toward those of bare supports after 15 h seemingly due to the water-involved membrane degradation. This study provides the availability and limitation of ZIF-8 membranes for H-2 separations in stimulated biomass-derived syngas environments. (C) 2015 Elsevier Inc. All rights reserved.</P>

Insights into the adsorption capacity and breakthrough properties of a synthetic zeolite against a mixture of various sulfur species at low ppb levels

Vellingiri, K.,Kim, K.H.,Kwon, E.E.,Deep, A.,Jo, S.H.,Szulejko, J.E. Academic Press 2016 Journal of environmental management Vol.166 No.-

<P>The sorptive removal properties of a synthetic A4 zeolite were evaluated against sulfur dioxide (SO2) and four reference reduced sulfur compounds (RSC: hydrogen sulfide (H2S), methanethiol (CH3SH), dimethyl sulfide (DMS, (CH3)(2)S), and dimethyl disulfide (DMDS, CH3SSCH3). To this end, a sorbent bed of untreated (as-received) A4 zeolite was loaded with gaseous standards at four concentration levels (10-100 partper-billion (ppb (v/v)) at four different volumes (0.1, 0.2, 0.5, and 1 L increments) in both increasing (IO: 0.1-1.0 L) and decreasing volume order (DO: 1.0 to 0.1 L). Morphological properties were characterized by PXRD, FTIR, and BET analysis. The removal efficiency of SO2 decreased from 100% for all concentrations at 0.1 L (initial sample volume) to similar to 82% (100 ppb) or similar to 96% (10 ppb) at 3.6 L In contrast, removal efficiency of RSC was near 100% at small loading volumes but then fell sharply, irrespective of concentration (10-100 ppb) (e.g., 32% (DMS) to 52% (H2S) at 100 ppb). The adsorption capacity of zeolite, if expressed in terms of solid-gas partition coefficient (e.g., similar to the Henry's law constant (mmol kg(-1) Pa-1)), showed moderate variabilities with the standard concentration levels and S compound types such as the minimum of 2.03 for CH3SH (at 20 ppb) to the maximum of 13.9 for SO2 (at 10 ppb). It clearly demonstrated a notable distinction in the removal efficiency of A4 zeolite among the different S species in a mixture with enhanced removal efficiency of SO2 compared to the RSCs. (c) 2015 Elsevier Ltd. All rights reserved.</P>

Transmissibility of novel H7N9 and H9N2 avian influenza viruses between chickens and ferrets

Ku, K.B.,Park, E.H.,Yum, J.,Kim, H.M.,Kang, Y.M.,Kim, J.C.,Kim, J.A.,Kim, H.S.,Seo, S.H. 3M Company 2014 Virology Vol.450 No.-

Previous studies have shown that the H7N9 avian influenza virus cannot be transmitted efficiently between ferrets via respiratory droplets. Here, we studied the infectivity of the H7N9 avian influenza virus in chickens and its transmissibility from infected to naive chickens and ferrets. The H7N9 virus (A/Anhui/½013) replicated poorly in chickens and could not be transmitted efficiently from infected chickens to naive chickens and ferrets. H7N9 virus was shed from chicken tracheae for only 2 days after infection and from chicken cloacae for only 1 day after infection, while the H9N2 avian influenza virus, which is endemic in chickens in many Asian countries, was shed from tracheae and cloacae for 8 days after infection. Taken together, our results suggest that chickens may be a poor agent of transmission for the H7N9 virus to other chickens and to mammals, including humans.

Benzo(a)pyrene induced cell cycle arrest and apoptosis in human choriocarcinoma cancer cells through reactive oxygen species-induced endoplasmic reticulum-stress pathway

Kim, S.M.,Lee, H.M.,Hwang, K.A.,Choi, K.C. Pergamon ; Elsevier Science Ltd 2017 Food and chemical toxicology Vol.107 No.1

Cigarette smoke (CS) contains over 60 well established carcinogens. In this study, we examined the effects of benzo(a)pyrene (B(a)P), a main CS component, on the viability and apoptosis of JEG-3 and BeWo human choriocarcinoma cancer cell lines. An MTT assay confirmed that B(a)P decreased the cell viability of JEG-3 and BeWo cells in a dose-dependent manner. Additionally, Western blot (WB) assay revealed that protein expression of cyclin D and cyclin E decreased, while protein expression of p21 and p27 was increased in response to B(a)P treatment for 48 h. The changes in reactive oxygen species (ROS) levels in JEG-3 and BeWo cells exposed to B(a)P were also measured by a dichlorofluorescein diacetate (DCF-DA) assay, which revealed that ROS levels increased in response to B(a)P treatment for 48 h. WB assay also confirmed that each B(a)P treatment of JEG-3 and BeWo cells for 4 h promoted the expression of phosphorylated eukaryotic initiation factor 2 alpha protein (p-eIF2α) and C/EBP homologous protein (CHOP), which are known to be involved in ROS-mediated endoplasmic reticulum stress (ER-stress) related apoptosis. Overall, the protein expression of Bax (a pro-apoptosis marker) increased, while the expression of Bcl-xl (an anti-apoptotic marker) decreased and the number of apoptotic cells increased in response to B(a)P treatment for 48 h. Taken together, these results suggest that B(a)P has the potential to induce apoptosis of JEG-3 and BeWo human choriocarcinoma cancer cells by increasing the ROS level and simultaneously activating ER-stress.

Characterization of the pharmacokinetic disposition of levofloxacin in stallions after intravenous and intramuscular administration

GOUDAH, A.,ABO EL-SOOUD, K.,SHIM, J.-H.,SHIN, H.-C.,ABD EL-ATY, A. M. Blackwell Publishing Ltd 2008 JOURNAL OF VETERINARY PHARMACOLOGY AND THERAPEUTIC Vol.31 No.5

<P>The target of the present study was to investigate the plasma disposition kinetics of levofloxacin in stallions (<I>n</I> = 6) following a single intravenous (i.v.) bolus or intramuscular (i.m.) injection at a dose rate of 4 mg/kg bwt, using a two-phase crossover design with 15 days as an interval period. Plasma samples were collected at appropriate times during a 48-h administration interval, and were analyzed using a microbiological assay method. The plasma levofloxacin disposition was best fitted to a two-compartment open model after i.v. dosing. The half-lives of distribution and elimination were 0.21 ± 0.13 and 2.58 ± 0.51 h, respectively. The volume of distribution at steady-state was 0.81 ± 0.26 L/kg, the total body clearance (<I>Cl</I><SUB>tot</SUB>) was 0.21 ± 0.18 L/h/kg, and the areas under the concentration–time curves (<I>AUC</I>s) were 18.79 ± 4.57 &mgr;g.h/mL. Following i.m. administration, the mean <I>t</I><SUB>1/2el</SUB> and <I>AUC</I> values were 2.94 ± 0.78 h and 17.21 ± 4.36 &mgr;g.h/mL. The bioavailability was high (91.76% ± 12.68%), with a peak plasma mean concentration (<I>C</I><SUB>max</SUB>) of 2.85 ± 0.89 &mgr;g/mL attained at 1.56 ± 0.71 h (<I>T</I><SUB>max</SUB>). The <I>in vitro</I> protein binding percentage was 27.84%. Calculation of efficacy predictors showed that levofloxacin might have a good therapeutic profile against Gram-negative and Gram-positive bacteria, with an <I>MIC</I> ≤ 0.1 &mgr;g/mL.</P>

HWE(Hot Wall Epitaxy)에 의한 ZnIn_2S_4 박막 성장과 광전도 특성

홍광준,이관교,정준우,정경아,방진주,장현규,문종대,김혜숙 조선대학교 기초과학연구소 1999 自然科學硏究 Vol.22 No.1

HWE 방법에 의해 ZnIn_2S_4 박막을 Si(00) 기판 위에 성장시켰다. 증발원과 기판의 온도를 각각 610℃, 450℃로 하여 성장시킨 ZnIn_2S_4 박막의 이중 결정 X-선 요동곡선(DCRC)의 반폭치(FWHM)값이 245 arcsec로 가장 작았다. Van der Pauw 방법으로 Hall 효과를 측정하여 운반자농도의 1n n 대 1/T에서 구한 활성화에너지는 0.17eV로 측정되었다. Hall 이동도의 온도 의존성은 30K에서 100K까지는 불순물산란에 기인하고, 100K에서 293K까지는 격자산란에 기인한것으로 고찰되었다. 광전도셀의 특성으로 spectral response, 최대 허용소비전력(MAPD), 광전류와 암전류(pc/dc)의 비 및 응답시간을 측정하였다. S 증기분위기에서 열처리한 광전도 셀의 경우, 감도(??)는 0.99, pc/dc은 1.37x10^7, 그리고 최대 허용소비전력(MAPD)은 336mW, 오름시간(rise time)은 9ms, 내림시간(decay time)은 9.8ms로 가장 좋은 광전도 특성을 얻었다. The ZnIn_2S_4 thin films were grown on the Si(100) wafers by a hot wall epitaxy method(HWE). The source and substrate temperature are 610℃ and 450℃ respectively. The crystalline structure of epilayers was investigated by double crystal X-ray diffraction(DCXD). Hall effect on the sample was measured by the van der Pauw method and studied on the carrier density and mobility dependence on temperature. From Hall data, the mobility was increased in the temperature range 30K to 100K by impurity scattering and decreased in the temperature range 100K to 293K by the lattice scattering. In order to explore the applicability as a photoconductive cell, we measured the sensitivity(??), the ratio of photocurrent to darkcurrent(pc/dc), maximum allowable power dissipation(MAPD), spectral response and response time. The results indicated that the photoconductive characteristic were the best for the samples annealed in S vapor compare with in Zn, In, air and vacuum vapour. Then we obtained the sensitivity of 0.99, the value of pc/dc of 1.37x10^7, the MAPD of 336mW, and the rise and decay time of 9ms and 9.8ms, respectively.