Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

Radiation-induced conductivity in ferroelectric and paraelectric phases of poly(vinylidenefluoride-co-trifluoroethylene)

O comportamento da condutividade induzida por radiação-X (RIC) em copolímeros P(VDF/TrFE) de razões molares 60/40 e 70/30 em suas fases ferroelétrica (temperatura ambiente) e paraelétrica (acima de 110°C), foi estudado para diferentes condições ambientais. Foi observado que a RIC depende fortemente sobre a conformação molecular do polímero. Variaram-se parâmetros experimentais como campo elétrico aplicado, taxa de dose, atmosfera ambiente e, principalmente a temperatura. Medidas auxiliares como correntes termoestimuladas, calorimetria diferencial, espectroscopias infravermelho, ressonância eletrônica paramagnética, difração de raios-X, etc..., deram contribuições no sentido de entender modificações estruturais e morfológicas do material devido à radiação. Para análise dos resultados da condutividade induzida (RIC), foi usado o modelo de transporte em meios dispersivos desenvolvido por Arkhipov e colaboradores. Por meio de ajustes teórico-experimentais obtivemos parâmetros importantes do material como, a mobilidade dos portadores gerados, o coeficiente de recombinação, o parâmetro dispersivo, bem como a energia de geração de pares.The behavior of the radiation induced conductivity (RIC) by X-rays in P(VDF/TrFE) copolymers of 70:30 and 60:40 molar ratios, in their ferro and paraelectric phases, were studied in different environments. It was observed that the RIC depends strongly on the molecular conformation of the polymer. For the experiments several parameters were varied as the external applied field, the dose rate, the atmosphere and mainly the temperature. Auxiliar measurements as thermal stimulated currents, differential scanning calorimetry, EPR and IR spectroscopy, X-ray diffraction, etc..., were used in the sense to supply additional information about morphological and structural variations of the material due to the irradiation. For a complete analysis of the radiation induced conductivity results a dispersive transport model developed by Arkhipov et al was used. From the theoretical experimental fitting we obtained important parameters of the material: carrier mobility, recombination coefficient, dispersive parameter Q, as well as the pair-generation energy

Radiation-induced conductivity in ferroelectric and paraelectric phases of poly(vinylidenefluoride-co-trifluoroethylene)

O comportamento da condutividade induzida por radiação-X (RIC) em copolímeros P(VDF/TrFE) de razões molares 60/40 e 70/30 em suas fases ferroelétrica (temperatura ambiente) e paraelétrica (acima de 110°C), foi estudado para diferentes condições ambientais. Foi observado que a RIC depende fortemente sobre a conformação molecular do polímero. Variaram-se parâmetros experimentais como campo elétrico aplicado, taxa de dose, atmosfera ambiente e, principalmente a temperatura. Medidas auxiliares como correntes termoestimuladas, calorimetria diferencial, espectroscopias infravermelho, ressonância eletrônica paramagnética, difração de raios-X, etc..., deram contribuições no sentido de entender modificações estruturais e morfológicas do material devido à radiação. Para análise dos resultados da condutividade induzida (RIC), foi usado o modelo de transporte em meios dispersivos desenvolvido por Arkhipov e colaboradores. Por meio de ajustes teórico-experimentais obtivemos parâmetros importantes do material como, a mobilidade dos portadores gerados, o coeficiente de recombinação, o parâmetro dispersivo, bem como a energia de geração de pares.The behavior of the radiation induced conductivity (RIC) by X-rays in P(VDF/TrFE) copolymers of 70:30 and 60:40 molar ratios, in their ferro and paraelectric phases, were studied in different environments. It was observed that the RIC depends strongly on the molecular conformation of the polymer. For the experiments several parameters were varied as the external applied field, the dose rate, the atmosphere and mainly the temperature. Auxiliar measurements as thermal stimulated currents, differential scanning calorimetry, EPR and IR spectroscopy, X-ray diffraction, etc..., were used in the sense to supply additional information about morphological and structural variations of the material due to the irradiation. For a complete analysis of the radiation induced conductivity results a dispersive transport model developed by Arkhipov et al was used. From the theoretical experimental fitting we obtained important parameters of the material: carrier mobility, recombination coefficient, dispersive parameter Q, as well as the pair-generation energy

Not available

Um estudo sistemático de despolarização termoestimulada (DTE) foi feito com filmes de Teflon-Fep irradiados com luz ultravioleta. As amostras foram irradiadas em três diferentes situações, na temperatura ambiente: a) Sem contatos metálicos, b) Com contatos metálicos, mas descarregadas e c) Com contatos metálicos, mas previamente carregadas. Foram utilizados contatos de In, Al, Zn, Cu, Cr e Au. As amostras carregadas negativamente despolarizaram-se quase na sua totalidade quando tinham sido irradiadas e estavam com contatos de In, Al e Zn, além de apresentarem sensíveis alterações nas curvas de DTE quando comparadas com as normais. As amostras com os outros contatos metálicos não foram muito alteradas pela radiação. Usando um modelo simplificado foi possível analisar as respostas do pulso térmico das amostras com carga residual e mostrou-se que houve injeção de buracos no caso das amostras irradiadas e carregadas negativamente. Medidas separadas usando amostras com dois contatos levaram à mesma conclusão. As amostras carregadas positivamente apresentaram uma carga residual considerável nas amostras irradiadas, evidenciando a presença de armadilhas profundas para buracos no volume do Teflon-FepA systematic study of corona charged Teflon-Fep films previously irradiated with ultraviolet light by the thermal stimulated depolarization (TSD) was performed. The free surface was UV irradiated at room temperature under three different conditions: a) without a metallic contact on the other surface in a not yet charged sample. b) With a metallic contact in a not yet corona charged and c) With a metallic contact in a charged sample. Metallic contacts of In, Al, Zn, Cu, Cr and Au were used. The negatively charged samples become almost totally depolarized after the TSD when irradiated in both cases (b) and (c) of coated with In, Al and Zn contacts, showing also visible changes in the TSD curves as compared with the normal ones. Samples coating with Cu, Cr and Au contacts did not present major changes by the effect of UV radiation. Also, no effect was observed in case (a) whatsoever the nature of the electrode used. The analysis of the residual charge using the Heat Pulse Method (HPM) showed that positive charge was injected by the back electrode. Measurements with samples prepared as incase (b) above but now with a second contact seem also to indicate injection of positive charge. A simplified model is presented in order to explain the heat pulse response of negative irradiated samples. Positively corona charged samples under (a), (b) and (c) UV irradiation give different thermograms as compared as in unirradiated samples. The interpretation of the results is now more difficult but it seems that new deep hole traps are created by UV ligh

Not available

Um estudo sistemático de despolarização termoestimulada (DTE) foi feito com filmes de Teflon-Fep irradiados com luz ultravioleta. As amostras foram irradiadas em três diferentes situações, na temperatura ambiente: a) Sem contatos metálicos, b) Com contatos metálicos, mas descarregadas e c) Com contatos metálicos, mas previamente carregadas. Foram utilizados contatos de In, Al, Zn, Cu, Cr e Au. As amostras carregadas negativamente despolarizaram-se quase na sua totalidade quando tinham sido irradiadas e estavam com contatos de In, Al e Zn, além de apresentarem sensíveis alterações nas curvas de DTE quando comparadas com as normais. As amostras com os outros contatos metálicos não foram muito alteradas pela radiação. Usando um modelo simplificado foi possível analisar as respostas do pulso térmico das amostras com carga residual e mostrou-se que houve injeção de buracos no caso das amostras irradiadas e carregadas negativamente. Medidas separadas usando amostras com dois contatos levaram à mesma conclusão. As amostras carregadas positivamente apresentaram uma carga residual considerável nas amostras irradiadas, evidenciando a presença de armadilhas profundas para buracos no volume do Teflon-FepA systematic study of corona charged Teflon-Fep films previously irradiated with ultraviolet light by the thermal stimulated depolarization (TSD) was performed. The free surface was UV irradiated at room temperature under three different conditions: a) without a metallic contact on the other surface in a not yet charged sample. b) With a metallic contact in a not yet corona charged and c) With a metallic contact in a charged sample. Metallic contacts of In, Al, Zn, Cu, Cr and Au were used. The negatively charged samples become almost totally depolarized after the TSD when irradiated in both cases (b) and (c) of coated with In, Al and Zn contacts, showing also visible changes in the TSD curves as compared with the normal ones. Samples coating with Cu, Cr and Au contacts did not present major changes by the effect of UV radiation. Also, no effect was observed in case (a) whatsoever the nature of the electrode used. The analysis of the residual charge using the Heat Pulse Method (HPM) showed that positive charge was injected by the back electrode. Measurements with samples prepared as incase (b) above but now with a second contact seem also to indicate injection of positive charge. A simplified model is presented in order to explain the heat pulse response of negative irradiated samples. Positively corona charged samples under (a), (b) and (c) UV irradiation give different thermograms as compared as in unirradiated samples. The interpretation of the results is now more difficult but it seems that new deep hole traps are created by UV ligh

Propionibacterium acnes-killed attenuates the inflammatory response and protects mice from sepsis by modulating inflammatory factors

BACKGROUND: Sepsis is a systemic inflammation associated with infection caused by pathogenic micro-organisms with high mortality rates. OBJECTIVE: In this study, we investigated the protective effect of Propionibacterium acnes-killed against polymicrobial sepsis induced by cecal ligation and puncture. METHODS: The mice were treated by intramuscular route in 1, 3, 5, and 7 days before the cecal ligation and puncture induction. The control group animals received vehicle (saline solution 0.9%) and the animals of the treated group received the P. acnes-killed (0.4 mg/animal). After anesthesia, midline laparotomy was performed with exposure of cecum followed by ligature and one transverse perforation of the same, with a 18 G needle, for induction of lethal sepsis. After surgery, the cecum of the animals was replaced into the peritoneal cavity, and it was closed with a 4.0 nylon suture. The survival of animals subjected to lethal sepsis was evaluated after cecal ligation and puncture induction. Six hours after the induction of sepsis, neutrophil migration, the number of bacteria, TNF-α, MCP-1, IL-6, and IL-10 were performed in the peritoneal lavage. RESULTS: Prophylactic treatment with P. acnes-killed increased the survival of the animals, followed by a significant decrease in the TNF-α, IL-10, and MCP-1 levels, 6 h after cecal ligation and puncture. Furthermore, P. acnes-killed administration reduced the number of bacteria in the peritoneal cavity with increased migration of leukocytes, especially neutrophils. CONCLUSION: P. acnes-killed promoted increased survival rate of animals with sepsis, in part attributed to its immunomodulatory properties against pathogenic microorganisms, as well as better control of infection by reducing bacterial counts