Long-term decline of the Amazon carbon sink.

Atmospheric carbon dioxide records indicate that the land surface has acted as a strong global carbon sink over recent decades, with a substantial fraction of this sink probably located in the tropics, particularly in the Amazon. Nevertheless, it is unclear how the terrestrial carbon sink will evolve as climate and atmospheric composition continue to change. Here we analyse the historical evolution of the biomass dynamics of the Amazon rainforest over three decades using a distributed network of 321 plots. While this analysis confirms that Amazon forests have acted as a long-term net biomass sink, we find a long-term decreasing trend of carbon accumulation. Rates of net increase in above-ground biomass declined by one-third during the past decade compared to the 1990s. This is a consequence of growth rate increases levelling off recently, while biomass mortality persistently increased throughout, leading to a shortening of carbon residence times. Potential drivers for the mortality increase include greater climate variability, and feedbacks of faster growth on mortality, resulting in shortened tree longevity. The observed decline of the Amazon sink diverges markedly from the recent increase in terrestrial carbon uptake at the global scale, and is contrary to expectations based on models.

Prevention educational program of human rabies transmitted by bats in rain forest preserved area of southern Brazilian coast.

Guaraqueçaba city is a rain forest environmental protected area located on the southern coast of Brazil. Recently, the local Animal Health Service has noticed haematophagous bats feeding from humans and domestic animals, as well as bat colonies located in houses and public schools. In 2007, two non-haematophagous bats were tested positive by direct immunofluorescence for rabies in a nearby city. Native fauna and environmental laws protect non-haematophagous bats in Brazilian preserved areas such as Guaraqueçaba, making non-haematophagous bat population control almost impossible. Accordingly, the aim of this study was to evaluate a simple and feasible educational protocol applied by a multi-institutional task force in local elementary schools to prevent rabies transmitted by bats. Information was transmitted to children by video, lectures and oral question-answer section; evaluation was made by written questionnaires to teachers and students. Interinstitutional task force included public and animal health public services, a federal university and the city secretary of environment, of education, of agriculture and of animal health, and also participation of local community. Information was effectively absorbed by children when evaluated just after being given. As important, questionnaires showed that handling and playing with bats at day time was common in several elementary school students, exposing themselves to what may represent higher risk of rabies transmission than haematophagous bat feeding directly from humans. Training of teachers and students may effectively prevent rabies by bats in such communities. Insertion of this subject into science content of local elementary school educational programme was proposed in order to establish a continuing education programme on rabies transmitted by bats in environmental preserved areas.

[Fetal hydronephrosis: postnatal management and follow up]. / Hidronefrose fetal: abordagem pós-natal e seguimento.

OBJECTIVE: Fetal hydronephrosis is being detected with increasing frequency and probably this observation will increase as the quality of ultrasound equipment improves. This study evaluated etiology and postnatal clinical outcomes of prenatally detected hydronephrosis. METHODS: In a period of 13 years 148 infants were referred with fetal hydronephrosis. The initial evaluation, after prophylaxis, included ultrasound and voiding cystography. Sequential evaluation was determined by initial findings. RESULTS: Postnatal predominant diagnosis were pelviureteric junction obstruction (24%) and hydronephrosis without obstruction (18%). Follow up median was 38.7 months. Renal function deteriorated in 13 (8.8%) children and 11 (7.4%) died during follow up. Bad prognosis was associated with urethral obstruction. CONCLUSIONS: Fetal hydronephrosis is a clue of urinary tract anomalies. Urinary tract infections and delay in postnatal diagnosis must be prevented in children with this uropathy.

Diffuse encephalic calcification. A case report.

The basal ganglia calcification is known since the last century but with the new neuroimage techniques (CT scan) its diagnosis became more frequent specially in asymptomatic patients. The authors report a case with non-familial primary diffuse encephalic calcification with exuberant calcifications on cerebral hemispheres, cerebellum and brain stem, seen on CT scan.

Thickness and refractive index dispersion measurement in a thin film using the Haidinger interferometer.

A Haidinger interferometer setup was adapted for accurate measurement of thickness and refractive index dispersion in transparent films using some spectral lines of a commercial argon-ion laser. Experimental results are reported and compared with those from other available methods.