15 research outputs found
A construção do cérebro dependente: uma análise da mídia brasileira e da literatura científica sobre adição a tecnologias
Neuroscience is frequently used as an argument in various debates on mental health, such as the definition of some behaviors as pathological. To understand how this happens in the Brazilian media, we analyzed neuroscientific facts mentioned in articles about a controversial diagnosis: internet and or/video gaming addiction. Of 85 articles located in web searches of seven major press vehicles, 25% made allusions to neuroscience. The analysis of two frequently mentioned facts (the similarity between cerebral alterations observed in drug and technology addictions and the release of dopamine as a mediator of reward and addiction to video games) showed inconsistencies between media claims and the available empirical evidence. However, similar biases were already observable in the scientific literature itself, suggesting that the theory of a “dependent brain” in behavioral and chemical addictions seems to be favored by both journalists and scientistsA neurociência é frequentemente usada como um argumento em diversos debates sobre saúde mental, tais como a definição de alguns comportamentos como patológicos. Para compreender como isto ocorre na mídia brasileira, analisamos fatos neurocientíficos mencionados em artigos sobre um diagnóstico ainda controverso, a dependência de jogos eletrônicos e/ou internet. Dos 85 artigos localizados em 7 grandes veículos de imprensa online, 25% faziam alusões à neurociência. A análise de dois fatos frequentemente mencionados (a similaridade das alterações cerebrais observadas nas dependências de tecnologia e drogas e a liberação de dopamina como mediador de recompensa e adição a jogos eletrônicos) demonstra inconsistências entre as afirmações na mídia e a evidência empírica disponível. No entanto, vieses semelhantes foram encontrados na própria literatura científica, sugerindo que interpretações relacionadas à existência de um “cérebro dependente” em adições químicas e comportamentais parecem ser favorecidas tanto entre jornalistas quanto entre cientista
Abundância de gavião-real e gavião-real falso numa área sob impacto de reservatório no Baixo e Médio rio Xingu
In the Brazilian Amazon, two monospecific genera, the Harpy Eagle and Crested Eagle have low densities and are classified by IUCN as Near Threatened due to habitat loss, deforestation, habitat degradation and hunting. In this study, we evaluate occurrence of these large raptors using the environmental surveys database from Belo Monte Hydroelectric Power Plant. Integrating the dataset from two methods, we plotted a distribution map along the Xingu River, including records over a 276-km stretch of river. Terrestrial surveys (RAPELD method) were more efficient for detecting large raptors than standardized aquatic surveys, although the latter were complementary in areas without modules. About 53% of the records were obtained during activities of wildlife rescue/flushing, vegetation suppression or in transit. Between 2012 and 2014, four Harpy Eagles were removed from the wild; two shooting victims, one injured by collision with power lines and one hit by a vehicle. Also, seven nests were mapped. The mean distance between Harpy Eagle records was 15 km along the river channel, with a mean of 20 km between nests near the channel, which allowed us to estimate 20 possible pairs using the alluvial forest, riverine forest and forest fragments. Territories of another ten pairs will probably be affected by inundation of the Volta Grande channel, which is far from the main river. The average distance between Crested Eagle records was 16 km along the river channel. The only nest found was 1.3 km away from a Harpy Eagle nest. The remnant forests are under threat of being replaced by cattle pastures, so we recommend that permanently protected riparian vegetation borders (APP) be guaranteed, and that forest fragments within 5 km of the river be conserved to maintain eagle populations. © 2015, Instituto Internacional de Ecologia. All rights reserved
Avaliação da correção da energia pelo balanço de nitrogênio em alimentos para frangos de corte
Efeito da base genética materna e da estação de parição sobre variáveis produtivas de fêmeas primíparas Holandês x Zebu Effect of the maternal genetic basis and of the calving season on productive variables of primiparous Holstein x Zebu cows
Avaliaram-se variáveis produtivas de 78 fêmeas primíparas mestiças de base genética materna Gir ou Guzerá, paridas na estação seca ou chuvosa, utilizando-se o procedimento GLM do SAS. A estação de parição interferiu (P<0,05) no peso ao parto (PP), no escore da condição corporal ao parto (ECCP), no ganho de peso durante a gestação, no período de serviço (PS) e no intervalo de partos (IDP). O PP e ECCP foram maiores (P<0,05) nas primíparas que pariram na estação seca em relação às que pariram na estação chuvosa. Os valores foram de 475,19±39,81kg, 4,07±0,44 e 420,67±37,80kg e 3,62±0,37, respectivamente, para a estação seca e chuvosa. O PS e o IDP foram menores (P<0,05) entre as vacas que pariram na estação seca, 132,02±91,94 dias e 13,90±3,06 meses, em relação às paridas na estação chuvosa, 190,07±77,27 dias e 15,84±2,58 meses. As fêmeas de base genética Gir apresentaram melhor desempenho (P<0,05) que as de base genética Guzerá para as características produção de leite, duração da lactação e produção de leite por dia de intervalo de partos, cujos valores, nessa ordem, foram de 2276,15±656,47kg, 306,08±46,55 dias, 5,06±1,38kg/dia para as fêmeas de base Gir e de 1733,74±678,41kg, 265,62±67,11 dias, 4,37±1,68kg/dia para as de base Guzerá.<br>Productive variables of 78 crossbred Holstein x Zebu primiparous cows of Gir or Guzera maternal genetic basis, calved in the dry or rainy season were evaluated using the GLM procedure of the SAS. The calving season affected the weight at calving (WC), body condition score at calving (BCS), service period (SP) and calving interval (CI). The WC and BCS were higher (P<0.05) por cows calved in the dry season, 475.19±39.81kg and 4.07±0.44, than in the rainy season, 420.67±37.80kg and 3.62±0.37, respectively. The SP and CI were shorter (P<0.05) for cows calved in the dry season, 132.02±91.94 days and 13.90±3.06 months, than cows calved in the rainy season, 190.07±77.27 days e 15.84±2.58 months, respectively. The Gir based cows had higher milk yield, longer lactation period and higher milk yield per day of calving interval than the Guzera based cows, respectively, 2276.15±656.47kg, 306.08±46.55 days, 5.06±1.38kg/day for the Gir and 1733.74±678.41kg, 265.62±67.11 days, 4.37±1.68kg/day for the Guzera based cows
Associations between socio-environmental factors and landscape-scale biodiversity recovery in naturally regenerating tropical and subtropical forests
Natural regeneration is key for large-scale forest restoration, yet it may lead to different biodiversity outcomes depending on socio-environmental context. We combined the results of a global meta-analysis to quantify how biodiversity recovery in naturally regenerating forests deviates from biodiversity values in reference old-growth forests, with structural equation modeling, to identify direct and indirect associations between socioeconomic, biophysical and ecological factors and deviation in biodiversity recovery at a landscape scale. Low deviation within a landscape means higher chances of multiple sites in naturally regenerating forests successfully recovering biodiversity compared to reference forests. Deviation in biodiversity recovery was directly negatively associated with the percentage of cropland, forest cover, and positively associated with the percentage of urban areas in the surrounding landscape. These three factors mediated the indirect associations with rural population size, recent gross deforestation, time since natural regeneration started, mean annual temperature, mean annual water deficit, road density, land opportunity cost, percentage cover of strictly protected forest areas, and human population variation in the surrounding landscape. We suggest that natural forest restoration should be prioritized in landscapes with both low socioeconomic pressures on land use conversion to pasturelands and urban areas, and high percentage of forest cover
Efeito dos níveis de energia para poedeiras comerciais no período final de produção sobre o desempenho, a conversão alimentar e energética e a qualidade de ovos
Improved Performance of ELISA and Immunochromatographic Tests Using a New Chimeric A2-Based Protein for Human Visceral Leishmaniasis Diagnosis
Summary. Human visceral leishmaniasis (VL) is a major public health problem worldwide, leading to significant mortality rates if not properly treated and controlled. Precise identification of infected patients is essential to establish treatment and control measures. Although several VL serological diagnosis advances have been accomplished lately, mainly using recombinant antigens and immunochromatographic tests (ICTs), improvements may still be achieved using multiepitope chimeric proteins in different test platforms. Here, we reported on the evaluation of ELISA and an ICT developed with a new chimeric protein, named DTL-4, based on repetitive antigenic sequences, including those present in the A2 protein. Methods. A total of 1028 sera samples were used for the development and validation of ELISA (321 samples from L. infantum-infected patients, 62 samples from VL/AIDS coinfected patients, 236 samples from patients infected with other diseases, and 409 samples from healthy donors). A total of 520 sera samples were used to develop and validate ICT (249 samples from L. infantum-infected patients, 46 samples from VL/AIDS coinfected patients, 40 samples from patients infected with other diseases, and 185 samples from healthy donors). Findings. Using the validation sera panels, DTL-4-based ELISA displayed an overall sensitivity of 94.61% (95% CI: 89.94-97.28), a specificity of 99.41% (95% CI: 96.39-99.99), and an accuracy of 97.02% (95% CI: 94.61-98.38), while for ICT, sensitivity, specificity, and accuracy values corresponded to 91.98% (95% CI: 86.65-95.39), 100.00% (95% CI: 96.30-100.00), and 95.14% (95% CI: 91.62-97.15), respectively. When testing sera samples from VL/AIDS coinfected patients, DTL-4-ELISA displayed a sensitivity of 77.42% (95% CI: 65.48-86.16), a specificity of 99.41% (95% CI: 96.39-99.99), and an accuracy of 93.51% (95% CI: 89.49%-96.10%), while for DTL-4-ICT, sensitivity was 73.91% (95% CI: 59.74-84.40), specificity was 90.63% (95% CI: 81.02-95.63), and accuracy was 82.00% (95% CI: 73.63-90.91). Conclusion. DTL-4 is a promising candidate antigen for serodiagnosis of VL patients, including those with VL/AIDS coinfection, when incorporated into ELISA or ICT test formats
Socioeconomic status and age at menarche in indigenous and non-indigenous Chilean adolescents Nivel socioeconómico y edad de la menarquia en adolescentes chilenas indígenas y no indígenas
The objective was to analyze the relationship between socioeconomic status and age at menarche among indigenous and non-indigenous girls in the Araucanía Region of Chile, controlling for nutritional status and mother's age at menarche. A total of 8,624 randomly selected girls from 168 schools were screened, resulting in the selection of 207 indigenous and 200 non-indigenous girls who had recently experienced menarche. Age at menarche was 149.6±10.7 months in the indigenous group and 146.6±10.8 months in the non-indigenous group. Among the non-indigenous, the analysis showed no significant association between age at menarche and socioeconomic status. In the indigenous group, age at menarche among girls with low socioeconomic status was 5.4 months later than among those with higher socioeconomic status. There were no differences in nutritional status according to socioeconomic level. Obesity was associated with earlier menarche. Menarche occurred earlier than in previous generations. An inverse relationship between socioeconomic status and age at menarche was seen in the indigenous group only; low socioeconomic status was associated with delayed menarche, regardless of nutritional status or mother's age at menarche.<br>El objetivo fue analizar la relación entre nivel socioeconómico y edad de menarquia en adolescentes indígenas y no indígenas de la Región de la Araucanía, Chile, controlando el efecto del estado nutricional, y la edad de menarquia de las madres. Se estudiaron 8.624 niñas de 168 escuelas elegidas aleatoriamente, seleccionando 207 indígenas y 200 no indígenas que habían tenido recientemente la menarquia. La edad de menarquia ocurrió a los 149,6±10,7 meses en indígenas y a los 146,6±10,8 meses en no indígenas. En el grupo no indígena, hubo una relación significativa entre edad de menarquia y nivel socioeconómico. En el grupo indígena, edad de menarquia del nivel socioeconómico bajo fue de 5,4 meses más tarde que el nivel socioeconómico más alto. No se observaron diferencias de estado nutricional por nivel socioeconómico. La obesidad adelantó la menarquia y la edad de menarquia ocurrió antes que la de sus madres. Existe una relación inversa entre nivel socioeconómico y edad de menarquia sólo en el grupo indígena; en los niveles socioeconómicos más bajos la edad de menarquia se retrasa independiente del estado nutricional y de la edad de menarquia de la madre