PREPARING THE EXPERTS FOR EMERGENCIES

Brown,J,D 한국화재소방학회 2000 한국화재소방학회 학술대회 논문집 Vol.2000 No.추계

삼각기둥의 Stereology 문제에 관한 이론적 고찰

Browne, J. D.,Jaffrey, D,이주완 대한금속재료학회(대한금속학회) 1984 대한금속·재료학회지 Vol.22 No.9

A theoretical model has been developed to calculate the aspect ratio distribution generated by random sectioning of an equilateral triangular prism. The calculations also show the extent to which this distribution depends upon the dimensional ratio of the prism. The results suggest that it would be feasible to compare the calculated and experimentally determined aspect ratio distributions and thereby establish the dimensional ratio of the real prisms.

Effects of cyclosporin A treatment on the pathogenesis of avian leukosis virus subgroup J infection in broiler chickens with Marek’s disease virus exposure

김용백,Thomas P. Brown,Mary J. Pantin-Jackwood 대한수의학회 2003 Journal of Veterinary Science Vol.4 No.3

In this study, we investigated the effects of T-cell suppression on the pathogenesis of subgroup J avian leukosis virus (ALV-J). Chickens were treated with cyclosporin A (CSP) 50 mg/Kg body weight or a corresponding volume of olive oil per every three days after hatching until the end of experiment. Some of the chickens from each treatment group were infected with an isolate of ALV-J, ADOL-7501, at 2 weeks of age. The effects of viral infection were compared to uninfected birds in same treatment group. Intramuscular injection of CSP induced significant T-cell specific immunosuppression determined by decreased cutaneous basophilic hypersensitivity response and decreased lymphocyte mitogenic activity using concanavalin A. Most of the chickens examined had Marek’s disease virus infection prior to 3 weeks of age. The percentage of antibody-positive birds and antibody titers were similar in infected chickens between both treatment groups. The ratio of viremic chickens was significantly higher in CSP treated group than that of the Oil treated group. Microscopically, one CSP treated chicken had a nephroblastoma at 10 weeks post infection. At 7 and 10 weeks post-infection, more chickens had myeloid cell infiltrations in multiple organs including heart, liver and occasionally lung. Expression of ALV-J viral antigen determined by immunohistochemical staining was significantly higher in CSP treated chickens than Oil treated chickens at 10 weeks post-infection. This study indicated that chemically-induced T-cell suppression may enhance pathogenicity of the AVL-J virus in broilers.

The effects of cyclophosphamide treatment on the pathogenesis of subgroup J avian leukosis virus(ALV-J)infection in broiler chickens with Marek's disease virus exposure

Yong-baek Kim,Thomas P. Brown,Mary J. Pantin-Jackwood 대한수의학회 2004 Journal of Veterinary Science Vol.5 No.1

Studies were performed to determine the effects of Bcell suppression on the pathogenesis of Subgroup J avian leukosis virus (ALV-J) in broiler chickens. Neonatal chickens were treated with cyclophosphamide (CY) or PBS, and then infected with ALV-J (ADOL-7501) at 2 weeks of age. CY treatment induced B cell specific immunosuppression throughout the experiment confirmed by decreased bursal weight, intact lymphocyte mitogenetic activity stimulated by Con A and increased relative subpopulation of CD3-positive cells as measured by flow cytometry. Chickens in this experiment had Mareks disease virus exposure prior to three weeks of age as determined by the presence of lymphocytic infiltration and antibody. Virus neutralizing antibody against ALV-J was first observed at 6 weeks post-infection in some of the infected chickens in the PBS group. As expected, none of the chickens from the CY group and uninfected chickens developed virus-neutralizing antibody. The viremic status was measured by real time RT-PCR using SYBR green I dye. The percentage of viremic chickens was significantly higher, and more chickens had high titered viremia, in the CY treated group. No neoplastic foci consistent with ALVJ infection were observed in any of the experimental chickens. The frequency and intensity of viral antigen expression determined by immunohistochemistry was significantly higher in tissues from CY treated birds than those of PBS treated chickens at 3 weeks post-infection. This study showed that B cell specific immunosuppression with CY treatment in chickens resulted in increase in viremia and viral antigen load in tissues.

Interaction of Beef Growth Type${\times}$Production System for Carcass Traits of Steers

Brown , A.H. Jr.,Camfield, P.K.,Johnson, Z.B.,Rakes, L.Y.,Pohlman, F.W.,Brown, C.J.,Sandelin, B.A.,Baublits, R.T. Asian Australasian Association of Animal Productio 2005 Animal Bioscience Vol.18 No.2

Steers (n=335) of known genetic backgrounds from four fundamentally different growth types were subjected to two production systems to study differences in carcass traits. Growth types were animals with genetic potential for large mature weight-late maturing, intermediate mature weight-late maturing, intermediate mature weight-early maturing and small mature weight-early maturing. Each year, in a nine-year study, calves of each growth type were weaned and five steers of each growth type were developed on pasture or feedlot and slaughtered at approximately 20 and 14 months of age, respectively. Data collected were pre-slaughter shrunk body weight (SBW); hot carcass weight (HCW); dressing percentage (DRESS); fat thickness at the $12^{th}$ and $13^{th}$ rib interface (FAT); percentage kidney, pelvic, and heart fat (KPH); longissimus muscle area (LMA); marbling score (MARB); quality grade (QG); and yield grade (YG). Year and growth type were significant for all carcass traits. The growth type${\times}$production system interaction was an important source of variation in SBW, HCW; FAT, YG and MARB. The same interaction was non-significant for DRESS, KPH, LMA and QG. Carcass differences in measures of fatness were greater in the feedlot system than in the pasture system. These data could aid producers in matching beef growth type to the production system most suitable for efficient use of resources.

A temperature-based approach to predicting lost data from highly seasonal pollutant data sets

Brown, Richard J. C.,Brown, Andrew S.,Kim, Ki-Hyun The Royal Society of Chemistry 2013 Environmental science Vol.15 No.6

<P>A new technique to predict concentrations of benzo[<I>a</I>]pyrene (B<I>a</I>P) in ambient air during periods of lost data has been developed and tested. This new technique is based on the relationship between ambient temperature and B<I>a</I>P concentration observed at individual monitoring stations over many years. The technique has been tested on monthly data of B<I>a</I>P concentrations in PM<SUB>10</SUB> at individual monitoring stations on the UK PAH Monitoring Network. The annual average concentration values produced with and without the use of predicted data have been compared to the actual annual averages in the absence of any data loss. The use of predicted data is a significant improvement when compared with the averages produced in the absence of any data prediction and outperforms previous prediction strategies associated with intra-year trends. Furthermore the technique is suitable for the prediction of long periods of missing data, which other prediction techniques have not been able to deal with satisfactorily.</P> <P>Graphic Abstract</P><P>A temperature-based approach to predicting lost data from highly seasonal pollutant data sets is presented. <IMG SRC='http://pubs.rsc.org/services/images/RSCpubs.ePlatform.Service.FreeContent.ImageService.svc/ImageService/image/GA?id=c3em00131h'> </P>

Who should take responsibility for decisions on internationally recommended datasets? The case of the mass concentration of mercury in air at saturation

Brown, Richard J C,Brewer, Paul J,Ent, Hugo,Fisicaro, Paola,Horvat, Milena,Kim, Ki-Hyun,Qu?tel, Christophe R BUREAU INTERNATIONAL DES POIDS ET MESURES 2015 METROLOGIA -BERLIN- Vol.52 No.5

<P>This paper considers how decisions on internationally recommended datasets are made and implemented and, further, how the ownership of these decisions comes about. Examples are given of conventionally agreed data and values where the responsibility is clear and comes about through official designation or by common usage and practice over long time periods. The example of the dataset describing the mass concentration of mercury in air at saturation is discussed in detail. This is a case where there are now several competing datasets that are in disagreement with each other, some with historical authority and some more recent but, arguably, with more robust metrological traceability to the SI. Further, it is elaborated that there is no body charged with the responsibility to make a decision on an international recommendation for such a dataset. This has led to the situation where several competing datasets are in use simultaneously. Close parallels are drawn with the current debate over changes to the ozone absorption cross section, which has equal importance to the measurement of ozone amount fraction in air and to subsequent compliance with air quality legislation. It is noted that in the case of the ozone cross section there is already a committee appointed to deliberate over any change. We make the proposal that a similar committee, under the auspices of IUPAC or the CIPM's CCQM (if it adopted a reference data function) could be formed to perform a similar role for the mass concentration of mercury in air at saturation.</P>

Fixed volume sequential standard addition calibration: Value assignment of impurities in zero gas

Brown, Richard J.C.,Brewer, Paul J.,Kim, Ki-Hyun Elsevier 2017 Chemometrics and intelligent laboratory systems Vol.164 No.-

<P><B>Abstract</B></P> <P>A fixed volume case of sequential standard addition calibration (S-SAC) for the value assignment of impurities in zero gas is described. A mathematical description of this technique has been derived and has been shown to exhibit a similar systematic bias during the extrapolation process to that seen for other S-SAC cases. The use of S-SAC in the gas phase has demonstrated that variation in the sample volume for S-SAC in the liquid phase is not the generalised cause of the bias experienced during extrapolation. Instead it is the variation in the volume of the original sample with respect to the overall volume of the mixture following the addition of standard. In addition, the requirement to perform a bias correction on the extrapolated values has been discussed and best practice solutions for correction proposed.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A fixed volume sequential standard addition calibration is described mathematically. </LI> <LI> This has been applied to the determination of impurities in blank gas. </LI> <LI> A systematic bias during the extrapolation process is observed. </LI> <LI> Best practice solutions for correction are proposed. </LI> </UL> </P>

Memory Effects on Adsorption Tubes for Mercury Vapor Measurement in Ambient Air: Elucidation, Quantification, and Strategies for Mitigation of Analytical Bias

Brown, Richard J. C.,Kumar, Yarshini,Brown, Andrew S.,Kim, Ki-Hyun American Chemical Society 2011 Environmental science & technology Vol.45 No.18

<P>The short- and long-term memory effects associated with measurements of mercury vapor in air using gold-coated silica adsorption tubes have been described. Data are presented to quantify these effects and to determine their dependence on certain relevant measurement parameters, such as number of heating cycles used for each analysis, age of adsorption tube, mass of mercury on adsorption tube, and the length of time between analyses. The results suggest that the long-term memory effect is due to absorption of mercury within the bulk gold in the adsorption tube, which may only be fully liberated by allowing enough time for this mercury to diffuse to the gold surface. The implications of these effects for air quality networks making these measurements routinely has been discussed, and recommendations have been made to ensure any measurement bias is minimized.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/esthag/2011/esthag.2011.45.issue-18/es201454u/production/images/medium/es-2011-01454u_0001.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/es201454u'>ACS Electronic Supporting Info</A></P>

Polycrystalline Graphene with Single Crystalline Electronic Structure

Brown, Lola,Lochocki, Edward B.,Avila, José,Kim, Cheol-Joo,Ogawa, Yui,Havener, Robin W.,Kim, Dong-Ki,Monkman, Eric J.,Shai, Daniel E.,Wei, Haofei I.,Levendorf, Mark P.,Asensio, Marí,a,Shen American Chemical Society 2014 NANO LETTERS Vol.14 No.10

<P>We report the scalable growth of aligned graphene and hexagonal boron nitride on commercial copper foils, where each film originates from multiple nucleations yet exhibits a single orientation. Thorough characterization of our graphene reveals uniform crystallographic and electronic structures on length scales ranging from nanometers to tens of centimeters. As we demonstrate with artificial twisted graphene bilayers, these inexpensive and versatile films are ideal building blocks for large-scale layered heterostructures with angle-tunable optoelectronic properties.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/nalefd/2014/nalefd.2014.14.issue-10/nl502445j/production/images/medium/nl-2014-02445j_0005.gif'></P><P><A href='http://pubs.acs.org/doi/suppl/10.1021/nl502445j'>ACS Electronic Supporting Info</A></P>