A C Carvalho

Universidade NOVA de Lisboa, Lisbon, Lisbon, Portugal

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Publications (4)13.06 Total impact

  • Source
    Article: Modelling the extreme precipitation event over Madeira Island on 20 February 2010
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    ABSTRACT: In the morning of the 20 February of 2010 an extreme precipitation event occurred over Madeira Island. This event triggered several flash floods and mudslides in the southern parts of the island, resulting in 42 confirmed deaths, 100 injured, and at least 8 people still missing. These extreme weather conditions were associated to a weather frontal system moving northeastwards embedded in a low pressure area centered in the Azores archipelago. This storm was one in a series of such storms that affected Portugal, Spain, Morocco and the Canary islands causing flooding and strong winds. These storms were bolstered by an unusually strong sea surface temperature gradient across the Atlantic Ocean. In this study, the WRF model is used to evaluate the intensity and predictability of this precipitation extreme event over the island. The synoptic/orographic nature of the precipitation is also evaluated, as well as the sensitivity of the model to horizontal resolution and cumulus parameterization. Orography was found to be the main factor explaining the occurrence, amplitude and phase of precipitation over the Island.
    Natural hazards and earth system sciences 09/2011; 11(9):2437-2452. · 1.98 Impact Factor
  • Article: Transmission of Mycobacterium tuberculosis to contacts of HIV-infected tuberculosis patients.
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    ABSTRACT: We assessed the infectiousness of human immunodeficiency virus (HIV)-seropositive and HIV-seronegative individuals with pulmonary tuberculosis (TB) in a prospective cohort study. We enrolled, evaluated, and followed 104 close contacts of HIV-seropositive pulmonary TB patients and 256 close contacts of HIV-seronegative pulmonary TB patients using a standardized questionnaire, symptom review, chest radiograph, HIV serology, and tuberculin skin testing (TST). Contacts were followed for > or = 12 mo. TB infection at enrollment was 27% (28/104) among contacts of HIV-seropositive TB patients and 35% (90/256) among contacts of HIV-seronegative TB patients (odds ratio [OR] = 0.68, 95% confidence interval [CI] 0.41 to 1.12; p = 0.130). TST conversion occurred in 21% (42/ 204) of subjects; 8% (5/63) of contacts of HIV-seropositive index cases and 26% (37/141) of contacts of HIV-seronegative index cases (OR = 0.24, 95% CI 0.09 to 0.65; p = 0.003). TB was diagnosed in nine contacts; eight were contacts of HIV-seronegative index cases. HIV seropositivity in the index case was independently associated with a lower risk of TB infection among contacts, even among household contacts younger than 15 yr of age. Contacts of HIV-seropositive persons with pulmonary TB were less likely to have a positive TST response at 1 yr of follow-up than contacts of HIV-seronegative persons.
    American Journal of Respiratory and Critical Care Medicine 12/2001; 164(12):2166-71. · 11.08 Impact Factor
  • Article: Tuberculosis as a cause of false-positive results in HIV screening EIA tests.
    Tubercle and Lung Disease 11/1994; 75(5):394-5.
  • Article: HIV infection in 567 active pulmonary tuberculosis patients in Brazil.
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    ABSTRACT: We studied 567 patients with active pulmonary tuberculosis (APT) in Rio de Janeiro, Brazil, by using a standardized questionnaire and by testing blood for HIV antibodies. The rate of HIV infection was 3.9% in 1987, 4.8% in 1988, and 5.2% in 1989, and did not differ by sex. It was highest (7.4%) in the 15- to 39-year age group. There was no difference between patients infected and not infected by HIV with regard to education, income, housing, or employment. Among all patients with definite HIV risk behavior, the HIV infection rate was 23.3%, rising to 31.2% among homo/bisexual men and 36.4% among intravenous drug users, and the rate was 6.5% for blood-transfusion recipients. Among patients who denied risk behavior, the rate was 1.2%. Generalized lymphadenopathy and oral candidiasis occurred with greater frequency among HIV-infected patients (p < 0.0001). Applying the World Health Organization 1985 clinical criteria and revised case definition for AIDS, we found, respectively, sensitivities of 34% and 76.9% and specificities of 31% and 26.3%; in the Rio de Janeiro environment, these clinical criteria without HIV serology should not be adopted for tuberculosis patients. For chest radiographs, a significant association was found between HIV infection and the occurrence of atypical images (p = 0.0001), and hilar and/or mediastinal adenopathy (p = 0.0002) and absence of cavities (p = 0.0003). A PPD (purified protein derivative) skin test induration of < 5 mm was identified in 53% of the HIV-positive cases and in 31.3% of the HIV-negative cases. Only 11.5% of HIV-infected APT patients met the Centers for Disease Control 1987 AIDS criteria.
    Journal of acquired immune deficiency syndromes 09/1993; 6(9):1008-12.