Accuracy versus precision in boosted top tagging with the ATLAS detector

Abstract The identification of top quark decays where the top quark has a large momentum transverse to the beam axis, known as top tagging, is a crucial component in many measurements of Standard Model processes and searches for beyond the Standard Model physics at the Large Hadron Collider. Machine learning techniques have improved the performance of top tagging algorithms, but the size of the systematic uncertainties for all proposed algorithms has not been systematically studied. This paper presents the performance of several machine learning based top tagging algorithms on a dataset constructed from simulated proton-proton collision events measured with the ATLAS detector at √ s = 13 TeV. The systematic uncertainties associated with these algorithms are estimated through an approximate procedure that is not meant to be used in a physics analysis, but is appropriate for the level of precision required for this study. The most performant algorithms are found to have the largest uncertainties, motivating the development of methods to reduce these uncertainties without compromising performance. To enable such efforts in the wider scientific community, the datasets used in this paper are made publicly available.</jats:p

Evaluation of schistosomiasis mansoni control measures in Sabara, Minas Gerais State, Brazil, 1980-2007

Schistosomiasis control programs in Brazil have helped reduce prevalence and the severe forms of the disease, but have failed to prevent new foci from appearing, especially on the periphery of large cities. The current article aims to assess the prevalence of schistosomiasis and the presence of intermediates hosts for Schistosoma mansoni in the district of Ravena, Municipality of Sabara, Minas Gerais State, Brazil, 27 years after implementing water treatment and specific treatment for infected individuals. Ravena responded positively to schistosomiasis control measures, with a prevalence of 2.5%. However, the district remains a potential risk area, since it displays favorable environmental and ecological factors for maintenance of the disease. For the prevalence rates to continue low, it will be necessary to invest in sanitation and health education, in addition to treatment of infected individuals.255996100

Condição auditiva de frentistas

OBJETIVO: avaliar os limiares auditivos nas frequências convencionais e altas frequências, e ainda a integridade do arco reflexo, em frentistas. MÉTODO: foram avaliados frentistas de três postos de gasolina da cidade de Santa Maria/RS. Após adequação aos critérios de inclusão, a amostra ficou composta por 24 frentistas expostos a combustíveis, 21 do gênero masculino e três do gênero feminino, com faixa etária entre 20 e 40 anos. Os exames utilizados foram audiometria tonal liminar, audiometria de altas frequências e imitanciometria. O tempo de exposição variou de um a 17 anos. O grupo controle foi composto por 24 sujeitos não expostos a qualquer agente nocivo à audição. RESULTADOS: a média dos limiares da audiometria tonal liminar e da audiometria de altas frequências foi superior no grupo estudo em todas as frequências testadas. Verificou-se diferença de limiar estatisticamente significante nas frequências de 0,5 (p=0,004), 2 (p=0,001) e 3 kHz (p=0,025), e nas frequências de 9 (p=0,007) e 10 kHz (p=0,026). Os limiares das frequências de 12,5 e 14 kHz não diferiram estatisticamente (p>0,05). Em 16, 18 e 20 kHz foi observada maior ausência de respostas no grupo estudo (p>0,05). Também se observou maior ausência de reflexos acústicos (ipsi e contralateral) no grupo estudo, na orelha direita. Na orelha esquerda, não houve diferença entre os grupos, para a ocorrência do reflexo ipsilateral. A ausência de reflexo contralateral foi maior no grupo estudo em todas as frequências testadas. CONCLUSÃO: frentistas com limiares auditivos normais podem apresentar alterações cocleares e centrais.PURPOSE: to evaluate the hearing threshold in the conventional frequencies and high frequencies, and the integrity of the acoustic reflex, in subjects exposed to fuels. METHOD: attendants of three gas stations were evaluated in Santa Maria/RS. After the adaptation to the inclusion criteria, the sample was composed of 24 subjects. It was used the Pure Tone Audiometry, high frequency audiometry and acoustic immitance assessment to evaluate the sample. The time of exposition ranged from one to seventeen years. The control group was composed by 24 not exposed subjects. RESULTS: the average of the thresholds of the PTA and of the high frequency audiometry was superior in the study group in all the tested frequencies. A statistically significant difference of thresholds was verified on the frequencies of 0,5 (p=0,004), 2 (p=0,001), 3 kHz (p=0,025), and frequencies of 9 (p=0,007) e 10 kHz (p=0,026). In 16, 18, 20 kHz a greater absence of responses was observed in the study group (p>0, 05). Also it was observed a greater absence of acoustic reflexes (ipsilateral and contralateral) at the study group, on the right ear. On the left ear, there was no difference between the groups, for the occurrence of ipsilateral reflex. The absence of the contralateral reflex was superior in the study group on all frequencies tested. CONCLUSION: individuals exposed to fuels with normal hearing thresholds may have cochlear and central alterations