305 research outputs found
EFEITOS DA TESTOSTERONA, ESTRADIOL OU PROGESTERONA NA DECOMPOSIÇÃO CORPORAL DE RATOS CASTRADOS
Previous results from our laboratory showed that males and females buried in the same place and in the same environmental conditions, conduct the male bodies to reach complete skeletonization before the female ones. So, it was decided to investigate if castrated male rats submitted to different steroid treatments showed different body decomposition patterns. Fifty male Wistar rats were anesthetized at 21 days of age and 40 of them were castrated while 10 were submitted to sham surgeries. The animals were divided into the following groups: Co- Control (sham surgery); Ca- Castreted; T- Testosterone (castrated + testosterone propionate); E- Estradiol (castrated + estradiol cipionate); P- Progesterone (castrated + progesterone). The animals were killed at 81 days of age in a CO2 chamber and were buried in the same grave. Exhumation was done 120 days after burial. The body decomposition was more advanced in the Group T, decreasingly followed by the Groups P, Co and Ca. The Group E was not considered in the analysis because of the significant if differences in body weight in comparison to the other groups in the time of death. The results indicate that steroid sexual hormones can interfere in the process of the body decomposition. This experimental biological model raises an important implication for forensic purposes, once hormonal profiles can induce different aspects of the body decomposition in the same interval of time, opening a precedent to justify investigation of human material to avoid doubts in the determination of the time since death in criminal investigations. Resultados prévios do nosso laboratório mostraram que ratos machos e fêmeas, quando sepultados em um mesmo local e sob as mesmas condições ambientais apresentam decomposição corporal diferenciada, com os corpos dos machos atingindo esqueletização completa antes das fêmeas. Então, decidiu-se investigar se ratos machos castrados submetidos a diferentes tratamentos com esteróides sexuais desenvolveriam padrões diferentes de decomposição corporal. Cinqüenta ratos Wistar machos foram anestesiados aos 21 dias de idade e 40 deles foram castrados enquanto 10 foram submetidos à cirurgia sham. Os animais foram divididos nos seguintes grupos: Co- Controle (cirurgia sham); Ca- Castrado; T- Testosterona (castração + propionato de testosterona); E- Estradiol (castração + cipionato de estradiol); P- Progesterona (castração + progesterona). Os animais foram mortos aos 81 dias de idade em câmara de CO2 e foram sepultados no mesmo local. A exumação foi feita 120 dias após o sepultamento. A decomposição corporal estava mais avançada no grupo T, seguindo decrescentemente pelos grupos P, Co e Ca. O grupo E não foi considerado nesta análise devido à diferença significativa no peso corporal no momento da morte em relação aos outros grupos. Os resultados indicaram que os hormônios esteróides sexuais podem interferir no processo de decomposição corporal. Esse modelo biológico experimental apresenta uma importante implicação forense, uma vez que perfis hormonais podem induzir diferentes aspectos na decomposição corporal no mesmo intervalo de tempo, abrindo um precedente para justificar a investigação em material humano para evitar dúvidas na determinação do tempo desde a morte em investigações criminais
Chromosomal, epigenetic and microRNA-mediated inactivation of LRP1B, a modulator of the extracellular environment of thyroid cancer cells
The low-density lipoprotein receptor-related protein (LRP1B), encoding an endocytic LDL-family receptor, is among the 10 most significantly deleted genes across 3312 human cancer specimens. However, currently the apparently crucial role of this lipoprotein receptor in carcinogenesis is not clear. Here we show that LRP1B inactivation (by chromosomal, epigenetic and microRNA (miR)-mediated mechanisms) results in changes to the tumor environment that confer cancer cells an increased growth and invasive capacity. LRP1B displays frequent DNA copy number loss and CpG island methylation, resulting in mRNA underexpression. By using CpG island reporters methylated in vitro, we found that DNA methylation disrupts a functional binding site for the histone-acetyltransferase p300 located at intron 1. We identified and validated an miR targeting LRP1B (miR-548a-5p), which is overexpressed in cancer cell lines as a result of 8q22 DNA gains. Restoration of LRP1B impaired in vitro and in vivo tumor growth, inhibited cell invasion and led to a reduction of matrix metalloproteinase 2 in the extracellular medium. We emphasized the role of an endocytic receptor acting as a tumor suppressor by modulating the extracellular environment composition in a way that constrains the invasive behavior of the cancer cells
INFLUENCE OF STEROID SEXUAL HORMONES ON SKELETIZATION TIME OF WISTAR RATS
The establishment of the postmortem interval is one of the most complicated and difficult tasks in forensic investigation because of many factors that affect this process (temperature, humidity, aerobic and anaerobic conditions, presence of microorganisms and soil conditions). Body intrinsic factors frequently not are related to de body decomposition. To investigate if the skeletonization process is under interference of sexual steroid hormones an experimental investigation with Wistar rats was done (30 male and 60 females divided in sub-groups at different hormonal phases). The animals were raised until they reach body weight between 350 and 450g, when were killed in a CO2 chamber and buried. Analysis of the environmental (temperature, humidity and rain) and corporal factors (body weight and body fat) showed that variation in these factors did not interfere on the skeletonization process. After the exhumation, only the male control group for testosterone showed complete skeletonization. The castrated males with no testosterone reposition and the castrated males with testosterone reposition showed minimum skeletonization. All female groups showed partial skeletonization. Analysis of the putrefaction residues from the groups with partial and minimum skeletonization showed the presence of the characteristic fatty acids of adipocere composition. Considering that both animal groups (males and females) were buried at the same place, under the same environmental and body conditions, during the same time interval, it is possible to conclude that sexual steroid hormones are responsible for the observed difference in body decomposition, being testosterone the main intervenient factor in this process. Besides, the experimental model also evidenced its potential use for future studies in the process of adipocere formation. A estimativa do tempo de morte é um dos problemas mais complicados e difíceis da Medicina Legal devido aos diversos fatores que interferem nesse processo (temperatura,umidade, condições aeróbica e anaeróbica, presença de microrganismos e condições do solo). Fatores intrínsecos ao corpo freqüentemente não são relacionados à decomposição corporal. Para investigar se o processo de esqueletização sofre interferência dos hormônios esteróides sexuais foi realizado um trabalho experimental com ratos Wistar (30 machos e 60 fêmeas divididos em subgrupos em diferentes fases hormonais). Os animais foram cuidados até atingirem o peso entre 350 e 450g, quando foram mortos em câmara de CO2 e sepultados. A análise dos fatores ambientais (temperatura, umidade do ar e chuvas) e corporais (peso e gordura corporal) mostrou que a variação destes não interferiu no processo de esqueletização. Após as exumações, apenas o grupo de machos controles para testosterona apresentou esqueletização completa. Os machos castrados sem reposição de testosterona e os machos castrados com reposição de testosterona apresentaram esqueletização mínima. Todos os grupos das fêmeas apresentaram esqueletização parcial. A análise dos resíduos de putrefação dos grupos com esqueletização mínima e parcial evidenciou a presença de ácidos graxos característicos da composição de adipocera. Considerando-se que os dois grupos de animais (machos e fêmeas) foram sepultados no mesmo local, sob as mesmas condições ambientais e corporais, durante o mesmo intervalo de tempo, é possível concluir que os hormônios esteróides sexuais são responsáveis pela diferença observada na decomposição corpórea, sendo a testosterona o principal interveniente neste processo. Além disso, o modelo experimental também evidenciou o potencial de utilização para ser utilizado futuramente em estudos do processo de formação de adipocera.
LAF 1.0: IMPLANTAÇÃO DE UM SISTEMA INFORMATIZADO PARA LABORATÓRIOS DE ANTROPOLOGIA FORENSE
Objective: A Software development for registration and recovery of information on Forensic Anthropology, based on the protocol developed during the project “UK – Brazil Scientific Cooperation – Forensic Anthropology and Identification of Human Remains”. Methods: Considering it is a Browser accessed application (software that allows Internet access, as Microsoft Internet Explorer®), it was necessary to choose an adequate programming language to this requirement as the server application. The chosen language was PHP® and the server application was Apache®. For data storage it was chosen the Data Bank Managing System MySQL®. Results: Tests performed with real data proved the LAF 1.0 efficiency, considering safety, reliability in storing and recovering data, as well as user satisfaction with clean, pleasant interfaces. This version was registered at the National Institute of Intellectual Property (INPI) and it is available for use in all medico-legal services interested in the creation of a Forensic Anthropology laboratory. Conclusions: The software improoved the generation of anthropological examination reports at Medico Legal Centre (CEMEL) and allowed the creation of a computerized tool for use in similar services, which will permit easiness in personal capacitating in Forensic Anthropology. Nowadays the software is in its updated version designated as LAF 2.0.Objetivo: Desenvolvimento de um software para cadastro e recuperação de informações em Antropologia Forense baseado no protocolo desenvolvido durante o projeto “UK –Brazil Scientific Cooperation – Forensic Anthropology and Identification of Human Remains”. Metodologia: Por se tratar de um aplicativo acessado via Browser (software que permite o acesso à Internet, como o Microsoft Internet Explorer®) foi necessária a escolha de uma linguagem de programação que se enquadrasse nesse requisito juntamente com uma aplicação servidora. A linguagem escolhida foi PHP® e a aplicação servidora foi o Apache®. Para o armazenamento dos dados foi escolhido o Sistema Gerenciador de Banco de Dados MySQL®. Resultados: Testes realizados com dados reais comprovaram a eficiência do LAF 1.0 em se tratando de segurança, confiabilidade no armazenamento e recuperação dos dados além de satisfação do usuário, com o visual limpo e agradável das interfaces. Esta versão foi registrada no Instituto Nacional de Propriedade Intelectual (INPI) e encontra-se disponível gratuitamente para uso em todos os serviços médico-legais interessados em implantar um laboratório de Antropologia Forense. Conclusões: O software agilizou a geração de laudos de exames antropológicos para o Laboratório de Antropologia Forense do Centro de Medicina Legal (CEMEL) e permitiu a criação de uma ferramenta informatizada gratuita para uso em outros serviços semelhantes, o que permitirá maior facilidade na capacitação de pessoal para o trabalho em Antropologia Forense. O software encontra-se atualmente em sua versão de atualização, denominada LAF 2.0.
Bartonella Clarridgeiae Bacteremia Detected In An Asymptomatic Blood Donor
Human exposure to Bartonella clarridgeiae has been reported only on the basis of antibody detection. We report for the first time an asymptomatic human blood donor infected with B. clarridgeiae, as documented by enrichment blood culture, PCR, and DNA sequencing.531352356Maggi, R.G., Duncan, A.W., Breitschwerdt, E.B., Novel chemically modified liquid medium that will support the growth of seven Bartonella species (2005) J Clin Microbiol, 43, pp. 2651-2655. , http://dx.doi.org/10.1128/JCM.43.6.2651-2655.2005Drummond, M.R., Pitassi, L.H., Lania, B.G., Dos Santos, S.R., Gilioli, R., Velho, P.E., Detection of Bartonella henselae in defibrinated sheep blood used for culture media supplementation (2011) Braz J Microbiol, 42, pp. 430-432. , http://dx.doi.org/10.1590/S1517-83822011000200003Altschul, S.F., Gish, W., Miller, W., Myers, E.W., Lipman, D.J., Basic local alignment search tool (1990) J Mol Biol, 215, pp. 403-410Dalton, M.J., Robinson, L.E., Cooper, J., Regnery, R.L., Olson, J.G., Childs, J.E., Use of Bartonella antigens for serologic diagnosis of cat-scratch disease at a national referral center (1995) Arch Intern Med, 155, pp. 1670-1676Breitschwerdt, E.B., Maggi, R.G., Chomel, B.B., Lappin, M.R., Bartonellosis: An emerging infectious disease of zoonotic importance to animals and human beings (2010) J Vet Emerg Crit Care (San Antonio), 20, pp. 8-30. , http://dx.doi.org/10.1111/j.1476-4431.2009.00496.xChamberlin, J., Laughlin, L.W., Romero, S., Solorzano, N., Gordon, S., Andre, R.G., Pachas, P., Watts, D., Epidemiology of endemic Bartonella bacilliformis: A prospective cohort study in a Peruvian mountain valley community (2002) J Infect Dis, 186, pp. 983-990. , http://dx.doi.org/10.1086/344054Maggi, R.G., Ericson, M., Mascarelli, P.E., Bradley, J.M., Breitschwerdt, E.B., Bartonella henselae bacteremia in a mother and son potentially associated with tick exposure (2013) Parasit Vectors, 6, p. 101. , http://dx.doi.org/10.1186/1756-3305-6-101Scott, M.A., McCurley, T.L., Vnencak-Jones, C.L., Hager, C., McCoy, J.A., Anderson, B., Collins, R.D., Edwards, K.M., Cat scratch disease: Detection of Bartonella henselae DNA in archival biopsies from patients with clinically, serologically, and histologically defined disease (1996) Am J Pathol, 149, pp. 2161-2167Slater, L.N., Welch, D.F., Min, K.W., Rochalimaea henselae causes bacillary angiomatosis and peliosis hepatis (1992) Arch Intern Med, 152, pp. 602-606Sander, A., Zagrosek, A., Bredt, W., Schiltz, E., Piemont, Y., Lanz, C., Dehio, C., Characterization of Bartonella clarridgeiae flagellin (FlaA) and detection of antiflagellin antibodies in patients with lymphadenopathy (2000) J Clin Microbiol, 38, pp. 2943-2948Kordick, D.L., Hilyard, E.J., Hadfield, T.L., Wilson, K.H., Steigerwalt, A.G., Brenner, D.J., Breitschwerdt, E.B., Bartonella clarridgeiae, a newly recognized zoonotic pathogen causing inoculation papules, fever, and lymphadenopathy (cat scratch disease) (1997) J Clin Microbiol, 35, pp. 1813-1818Margileth, A.M., Baehren, D.F., Chest-wall abscess due to cat-scratch disease (CSD) in an adult with antibodies to Bartonella clarridgeiae: Case report and review of the thoracopulmonary manifestations of CSD (1998) Clin Infect Dis, 27, pp. 353-357. , http://dx.doi.org/10.1086/514671Chomel, B.B., Mac Donald, K.A., Kasten, R.W., Chang, C.C., Wey, A.C., Foley, J.E., Thomas, W.P., Kittleson, M.D., Aortic valve endocarditis in a dog due to Bartonella clarridgeiae (2001) J Clin Microbiol, 39, pp. 3548-3554. , http://dx.doi.org/10.1128/JCM.39.10.3548-3554.2001Gillespie, T.N., Washabau, R.J., Goldschmidt, M.H., Cullen, J.M., Rogala, A.R., Breitschwerdt, E.B., Detection of Bartonella henselae and Bartonella clarridgeiae DNA in hepatic specimens from two dogs with hepatic disease (2003) J Am Vet Med Assoc, 222, pp. 47-51. , http://dx.doi.org/10.2460/javma.2003.222.47, 35Robinson, M.T., Hillman, T., Langton, D.A., Shaw, S.E., Bartonella clarridgeiae in a cat in the UK (2009) Vet Rec, 164, pp. 58-59. , http://dx.doi.org/10.1136/vr.164.2.58Sykes, J.E., Westropp, J.L., Kasten, R.W., Chomel, B.B., Association between Bartonella species infection and disease in pet cats as determined using serology and culture (2010) J Feline Med Surg, 12, pp. 631-636. , http://dx.doi.org/10.1016/j.jfms.2010.04.003Fouch, B., Coventry, S., A case of fatal disseminated Bartonella henselae infection (cat-scratch disease) with encephalitis (2007) Arch Pathol Lab Med, 131, pp. 1591-1594Boudebouch, N., Sarih, M., Beaucournu, J.C., Amarouch, H., Hassar, M., Raoult, D., Parola, P., Bartonella clarridgeiae, B. Henselae, and Rickettsia felis in fleas from Morocco (2011) Ann Trop Med Parasitol, 105, pp. 493-498. , http://dx.doi.org/10.1179/1364859411Y.0000000038Kordick, D.L., Brown, T.T., Shin, K., Breitschwerdt, E.B., Clinical and pathologic evaluation of chronic Bartonella henselae or Bartonella clarridgeiae infection in cats (1999) J Clin Microbiol, 37, pp. 1536-1547Chomel, B.B., Carlos, E.T., Kasten, R.W., Yamamoto, K., Chang, C.C., Carlos, R.S., Abenes, M.V., Pajares, C.M., Bartonella henselae and Bartonella clarridgeiae infection in domestic cats from the Philippines (1999) Am J Trop Med Hyg, 60, pp. 593-597Dehio, C., Bartonella interactions with endothelial cells and erythrocytes (2001) Trends Microbiol, 9, pp. 279-285. , http://dx.doi.org/10.1016/S0966-842X(01)02047-9Dehio, C., Meyer, M., Berger, J., Schwarz, H., Lanz, C., Interaction of Bartonella henselae with endothelial cells results in bacterial aggregation on the cell surface and the subsequent engulfment and internalisation of the bacterial aggregate by a unique structure, the invasome (1997) J Cell Sci, 110 (18), pp. 2141-2154Braga Mdo, S., Diniz, P.P., André, M.R., Bortoli, C.P., Machado, R.Z., Molecular characterisation of Bartonella species in cats from São Luís, state of Maranhão, North-Eastern Brazil (2012) Mem Inst Oswaldo Cruz, 107, pp. 772-777. , http://dx.doi.org/10.1590/S0074-02762012000600011Eremeeva, M.E., Gerns, H.L., Lydy, S.L., Goo, J.S., Ryan, E.T., Mathew, S.S., Ferraro, M.J., Koehler, J.E., Bacteremia, fever, and splenomegaly caused by a newly recognized Bartonella species (2007) N Engl J Med, 356, pp. 2381-2387. , http://dx.doi.org/10.1056/NEJMoa065987Chomel, B.B., Boulouis, H.J., Breitschwerdt, E.B., Kasten, R.W., Vayssier-Taussat, M., Birtles, R.J., Koehler, J.E., Dehio, C., Ecological fitness and strategies of adaptation of Bartonella species to their hosts and vectors (2009) Vet Res, 40, p. 29. , http://dx.doi.org/10.1051/vetres/2009011Breitschwerdt, E.B., Maggi, R.G., Duncan, A.W., Nicholson, W.L., Hegarty, B.C., Woods, C.W., Bartonella species in blood of immunocompetent persons with animal and arthropod contact (2007) Emerg Infect Dis, 13, pp. 938-941. , http://dx.doi.org/10.3201/eid1306.061337Carson, J.L., Grossman, B.J., Kleinman, S., Tinmouth, A.T., Marques, M.B., Fung, M.K., Holcomb, J.B., Djulbegovic, B., Red blood cell transfusion: A clinical practice guideline from the AABB (2012) Ann Intern Med, 157, pp. 49-58. , http://dx.doi.org/10.7326/0003-4819-157-1-201206190-00429Ramirez-Arcos, S., Goldman, M., Blajchman, M., Bacterial contamination (2012) Transfusion Reaction, 4, pp. 153-189. , Popovsky MA (ed), American Association Of Blood Banks, Bethesda, MDVamvakas, E.C., Blajchman, M.A., Transfusion-related mortality: The ongoing risks of allogeneic blood transfusion and the available strategies for their prevention (2009) Blood, 113, pp. 3406-3417. , http://dx.doi.org/10.1182/blood-2008-10-167643Magalhães, R.F., Cintra, M.L., Barjas-Castro, M.L., Del Negro, G.M., Okay, T.S., Velho, P.E., Blood donor infected with Bartonella henselae (2010) Transfus Med, 20, pp. 280-282. , http://dx.doi.org/10.1111/j.1365-3148.2010.01001.xMagalhães, R.F., Pitassi, L.H., Salvadego, M., De Moraes, A.M., Barjas-Castro, M.L., Velho, P.E., Bartonella henselae survives after the storage period of red blood cell units: Is it transmissible by transfusion? (2008) Transfus Med, 18, pp. 287-291. , http://dx.doi.org/10.1111/j.1365-3148.2008.00871.xLin, J.W., Chen, C.M., Chang, C.C., Unknown fever and back pain caused by Bartonella henselae in a veterinarian after a needle puncture: A case report and literature review (2011) Vector Borne Zoonotic Dis, 11, pp. 589-591. , http://dx.doi.org/10.1089/vbz.2009.0217Oliveira, A.M., Maggi, R.G., Woods, C.W., Breitschwerdt, E.B., Suspected needle stick transmission of Bartonella vinsonii subspecies berkhoffii to a veterinarian (2010) J Vet Intern Med, 24, pp. 1229-1232. , http://dx.doi.org/10.1111/j.1939-1676.2010.0563.xOhl, M.E., Spach, D.H., Bartonella quintana and urban trench fever (2000) Clin Infect Dis, 31, pp. 131-135. , http://dx.doi.org/10.1086/313890Daly, J.S., Worthington, M.G., Brenner, D.J., Moss, C.W., Hollis, D.G., Weyant, R.S., Steigerwalt, A.G., O'Connor, S.P., Rochalimaea elizabethae sp. Nov. Isolated from a patient with endocarditis (1993) J Clin Microbiol, 31, pp. 872-881Oksi, J., Rantala, S., Kilpinen, S., Silvennoinen, R., Vornanen, M., Veikkolainen, V., Eerola, E., Pulliainen, A.T., Cat scratch disease caused by Bartonella grahamii in an immunocompromised patient (2013) J Clin Microbiol, 51, pp. 2781-2784. , http://dx.doi.org/10.1128/JCM.00910-13Breitschwerdt, E.B., Mascarelli, P.E., Schweickert, L.A., Maggi, R.G., Hegarty, B.C., Bradley, J.M., Woods, C.W., Hallucinations, sensory neuropathy, and peripheral visual deficits in a young woman infected with Bartonella koehlerae (2011) J Clin Microbiol, 49, pp. 3415-3417. , http://dx.doi.org/10.1128/JCM.00833-11Raoult, D., Roblot, F., Rolain, J.M., Besnier, J.M., Loulergue, J., Bastides, F., Choutet, P., First isolation of Bartonella alsatica from a valve of a patient with endocarditis (2006) J Clin Microbiol, 44, pp. 278-279. , http://dx.doi.org/10.1128/JCM.44.1.278-279.2006Welch, D.F., Carroll, K.C., Hofmeister, E.K., Persing, D.H., Robison, D.A., Steigerwalt, A.G., Brenner, D.J., Isolation of a new subspecies, Bartonella vinsonii subsp. Arupensis, from a cattle rancher: Identity with isolates found in conjunction with Borrelia burgdorferi and Babesia microti among naturally infected mice (1999) J Clin Microbiol, 37, pp. 2598-2601Probert, W., Louie, J.K., Tucker, J.R., Longoria, R., Hogue, R., Moler, S., Graves, M., Fritz, C.L., Meningitis due to a "Bartonella washoensis"-like human pathogen (2009) J Clin Microbiol, 47, pp. 2332-2335. , http://dx.doi.org/10.1128/JCM.00511-09Kosoy, M., Morway, C., Sheff, K.W., Bai, Y., Colborn, J., Chalcraft, L., Dowell, S.F., Petersen, L.R., Bartonella tamiae sp. Nov., a newly recognized pathogen isolated from three human patients from Thailand (2008) J Clin Microbiol, 46, pp. 772-775. , http://dx.doi.org/10.1128/JCM.02120-07Maggi, R.G., Kosoy, M., Mintzer, M., Breitschwerdt, E.B., Isolation of Candidatus Bartonella melophagi from human blood (2009) Emerg Infect Dis, 15, pp. 66-68. , http://dx.doi.org/10.3201/eid1501.081080Lin, E.Y., Tsigrelis, C., Baddour, L.M., Lepidi, H., Rolain, J.M., Patel, R., Raoult, D., Candidatus Bartonella mayotimonensis and endocarditis (2010) Emerg Infect Dis, 16, pp. 500-503. , http://dx.doi.org/10.3201/eid1603.081673Breitschwerdt, E.B., Maggi, R.G., Cadenas, M.B., De Paiva Diniz, P.P., A groundhog, a novel Bartonella sequence, and my father's death (2009) Emerg Infect Dis, 15, pp. 2080-2086. , http://dx.doi.org/10.3201/eid1512.AD151
Measurement of the polarisation of W bosons produced with large transverse momentum in pp collisions at sqrt(s) = 7 TeV with the ATLAS experiment
This paper describes an analysis of the angular distribution of W->enu and
W->munu decays, using data from pp collisions at sqrt(s) = 7 TeV recorded with
the ATLAS detector at the LHC in 2010, corresponding to an integrated
luminosity of about 35 pb^-1. Using the decay lepton transverse momentum and
the missing transverse energy, the W decay angular distribution projected onto
the transverse plane is obtained and analysed in terms of helicity fractions
f0, fL and fR over two ranges of W transverse momentum (ptw): 35 < ptw < 50 GeV
and ptw > 50 GeV. Good agreement is found with theoretical predictions. For ptw
> 50 GeV, the values of f0 and fL-fR, averaged over charge and lepton flavour,
are measured to be : f0 = 0.127 +/- 0.030 +/- 0.108 and fL-fR = 0.252 +/- 0.017
+/- 0.030, where the first uncertainties are statistical, and the second
include all systematic effects.Comment: 19 pages plus author list (34 pages total), 9 figures, 11 tables,
revised author list, matches European Journal of Physics C versio
Observation of a new chi_b state in radiative transitions to Upsilon(1S) and Upsilon(2S) at ATLAS
The chi_b(nP) quarkonium states are produced in proton-proton collisions at
the Large Hadron Collider (LHC) at sqrt(s) = 7 TeV and recorded by the ATLAS
detector. Using a data sample corresponding to an integrated luminosity of 4.4
fb^-1, these states are reconstructed through their radiative decays to
Upsilon(1S,2S) with Upsilon->mu+mu-. In addition to the mass peaks
corresponding to the decay modes chi_b(1P,2P)->Upsilon(1S)gamma, a new
structure centered at a mass of 10.530+/-0.005 (stat.)+/-0.009 (syst.) GeV is
also observed, in both the Upsilon(1S)gamma and Upsilon(2S)gamma decay modes.
This is interpreted as the chi_b(3P) system.Comment: 5 pages plus author list (18 pages total), 2 figures, 1 table,
corrected author list, matches final version in Physical Review Letter
Search for displaced vertices arising from decays of new heavy particles in 7 TeV pp collisions at ATLAS
We present the results of a search for new, heavy particles that decay at a
significant distance from their production point into a final state containing
charged hadrons in association with a high-momentum muon. The search is
conducted in a pp-collision data sample with a center-of-mass energy of 7 TeV
and an integrated luminosity of 33 pb^-1 collected in 2010 by the ATLAS
detector operating at the Large Hadron Collider. Production of such particles
is expected in various scenarios of physics beyond the standard model. We
observe no signal and place limits on the production cross-section of
supersymmetric particles in an R-parity-violating scenario as a function of the
neutralino lifetime. Limits are presented for different squark and neutralino
masses, enabling extension of the limits to a variety of other models.Comment: 8 pages plus author list (20 pages total), 8 figures, 1 table, final
version to appear in Physics Letters
Measurement of the inclusive isolated prompt photon cross-section in pp collisions at sqrt(s)= 7 TeV using 35 pb-1 of ATLAS data
A measurement of the differential cross-section for the inclusive production
of isolated prompt photons in pp collisions at a center-of-mass energy sqrt(s)
= 7 TeV is presented. The measurement covers the pseudorapidity ranges
|eta|<1.37 and 1.52<=|eta|<2.37 in the transverse energy range 45<=E_T<400GeV.
The results are based on an integrated luminosity of 35 pb-1, collected with
the ATLAS detector at the LHC. The yields of the signal photons are measured
using a data-driven technique, based on the observed distribution of the
hadronic energy in a narrow cone around the photon candidate and the photon
selection criteria. The results are compared with next-to-leading order
perturbative QCD calculations and found to be in good agreement over four
orders of magnitude in cross-section.Comment: 7 pages plus author list (18 pages total), 2 figures, 4 tables, final
version published in Physics Letters
Measurement of D*+/- meson production in jets from pp collisions at sqrt(s) = 7 TeV with the ATLAS detector
This paper reports a measurement of D*+/- meson production in jets from
proton-proton collisions at a center-of-mass energy of sqrt(s) = 7 TeV at the
CERN Large Hadron Collider. The measurement is based on a data sample recorded
with the ATLAS detector with an integrated luminosity of 0.30 pb^-1 for jets
with transverse momentum between 25 and 70 GeV in the pseudorapidity range
|eta| < 2.5. D*+/- mesons found in jets are fully reconstructed in the decay
chain: D*+ -> D0pi+, D0 -> K-pi+, and its charge conjugate. The production rate
is found to be N(D*+/-)/N(jet) = 0.025 +/- 0.001(stat.) +/- 0.004(syst.) for
D*+/- mesons that carry a fraction z of the jet momentum in the range 0.3 < z <
1. Monte Carlo predictions fail to describe the data at small values of z, and
this is most marked at low jet transverse momentum.Comment: 10 pages plus author list (22 pages total), 5 figures, 1 table,
matches published version in Physical Review
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