Abstract
Changes in vegetation cover due to increasing frequencies of extreme climate events and anthropogenic pressure are already underway; so, predicting the impacts of the near‐future climate ...will be essential for developing mitigation strategies. We modelled the responses of Brazilian biomes to a future scenario (2070) of steady increases in atmospheric CO levels, adding soil data to better represent the multidimensional space of the environmental suitability of each biome. We also assessed the effects of changes in environmental suitability on the Brazilian network of protected areas and projected those effects on 1 km resolution maps. The area predicted to be affected by future climate change in Brazil and the consequent loss of suitable habitat surface is 2.59 Mkm
2
– larger than the combined areas of Central America and Mexico – leading the current vegetation to a progressive replacement. We project major changes in the vegetation of the Amazon basin, with the replacement of rainforest by dryer vegetation in the southern and eastern regions of that basin, and the opening of a dry corridor in Pará State. We also project an expansion of 41% of the current caatinga cover in the Brazilian semiarid region, with large losses of suitable habitat surface of the current deciduous forest. Approximately, 37% of the coverage of protected areas in Brazil will be affected – with greater damage to indigenous lands. The speed of current environmental change is now unprecedented for the post‐glacial era, and will almost certainly lead to increased rates of extinction and the collapse of transition ecosystems. We propose the urgent creation of protected areas in regions designed without significant impacts, but contiguous to those that will be more seriously affected by climate change. Those areas will act as refugia preserving biodiversity, ecosystem services, and the cultural heritages of traditional populations.
Resumo
As mudanças na cobertura vegetal devido ao aumento da frequência de eventos climáticos extremos e à pressão antropogênica já estão em andamento; portanto, prever os impactos do clima no futuro próximo será essencial para o desenvolvimento de estratégias de mitigação. Modelamos as respostas dos biomas brasileiros a um cenário futuro (2070) de aumentos constantes nos níveis de CO
2
atmosférico, acrescentando dados do solo para representar melhorar o espaço multidimensional da adequação ambiental de cada bioma. Também avaliamos os efeitos das mudanças na adequação ambiental sobre a rede brasileira de áreas protegidas e projetamos esses efeitos em mapas com resolução de 1 km. No Brasil, a área prevista para ser afetada pelas futuras mudanças climáticas e a consequente perda de superfície de adequabilidade de habitat é de 2,59 Mkm
2
– maior do que as áreas combinadas da América Central e do México – levando a uma substituição progressiva da vegetação atual. Estimamos grandes mudanças na vegetação da bacia amazônica, com a substituição da floresta tropical por uma vegetação mais seca nas regiões sul e leste da bacia e a abertura de um corredor seco no Estado do Pará. Também projetamos uma expansão de 41% da atual cobertura de caatinga na região semiárida brasileira, com grandes perdas de superfície de adequabilidade de habitat para a atual floresta decídua. Aproximadamente 37% da cobertura das áreas protegidas no Brasil será afetada, com maiores danos às terras indígenas. A velocidade da mudança ambiental atual não tem precedentes na era pós‐glacial e quase certamente levará ao aumento das taxas de extinção e ao colapso dos ecossistemas de transição. Propomos a urgente criação de áreas protegidas em regiões sem previsão de impactos significativos, mas contíguas àquelas que serão mais seriamente afetadas pelas mudanças climáticas. Essas áreas atuarão como refúgios, preservando a biodiversidade, os serviços ecossistêmicos e o patrimônio cultural das populações tradicionais.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Antarctic soils occur in restricted areas, but few integrated studies on soils and landforms have focused in the Antarctic Peninsula. We studied the representative soils of Hope Bay, emphasizing the ...processes of quaternary sedimentation, landforms, soil classification, and distribution. Results show that landforms and soils are closely associated in Hope Bay. Ornithogenic soils are associated with Late Pleistocene to Holocene stable ground moraines; these are currently being destroyed by thermokarst erosion around Lake Boekella. Lithic Haploturbels occur chiefly on shallow rocky terrains whereas Typic Haploturbels are found on patterned ground. In Hope Bay, a much colder climate prevails compared with the South Shetlands, and the widespread permafrost close to the surface warrants strong cryoclastic weathering with active and general gelifraction across different lithologies. The shallow occurrence of permafrost in Hope Bay has a strong regulating effect on soils, retarding leaching and soil development processes. Local soils are, in general, shallow and cryoturbic, and the current pedoenvironment on lowland stable areas was subjected to varying phosphatization on previously weathered sedimentary material. The evidence of phosphatization of a formerly larger area appears to be the main driver of pedogenesis at Hope Bay, and nesting activity by penguins on stable surfaces is capable of enhancing weathering and soil formation.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Abnormal multiplication of oral bacteria causes dental caries and dental plaque. These diseases continue to be major public health concerns worldwide, mainly in developing countries. In this study, ...the chemical composition and antimicrobial activity of the essential oil of Vitex agnus-castus leaves (VAC‒EO) collected in the North of Brazil against a representative panel of cariogenic bacteria were investigated. The antimicrobial activity of VAC-EO was evaluated in terms of its minimum inhibitory concentration (MIC) values by using the broth microdilution method in 96-well microplates. The chemical constituents of VAC-EO were identified by gas chromatography (GC‒FID) and gas chromatography‒mass spectrometry (GC‒MS). VAC‒EO displayed some activity against all the investigated oral pathogens; MIC values ranged from 15.6 to 200 μg/mL. VAC-EO had promising activity against Streptococcus mutans (MIC= 15.6 μg/mL), Lactobacillus casei (MIC= 15.6 μg/mL), and Streptococcus mitis (MIC= 31.2 μg/mL). The compounds 1,8-cineole (23.8%), (E)-β-farnesene (14.6%), (E)-caryophyllene (12.5%), sabinene (11.4%), and α-terpinyl acetate (7.7%) were the major chemical constituents of VAC‒EO. VAC-EO displays antimicrobial activity against cariogenic bacteria. The efficacy of VAC-EO against S. mutans is noteworthy and should be further investigated.
Monitoring permafrost and active layer is essential for prognostic research of future climate scenarios. Although biotic factors have a prominent role in active layer behavior, apart from vegetation ...effects, their influence remains little investigated. It is generally assumed that frozen ground exerts influence on nesting fauna, whereas, on the other hand, land colonization by birds, such as penguins can also interfere with the soil thermal regime. However, to our knowledge, no studies report on permafrost and active layer regime changes under penguin activity. We present a comparative study of two adjacent sites located in Hope Bay, one representing an active penguin rookery-S1, and another, an adjacent abandoned site currently vegetated-S2. Soil temperature and water content, and air temperature were monitored hourly from 2009 to 2011. Current penguin activity and the resulting deposition of guano during spring and summer in S1 is an important factor for explaining the higher number of thaw degree days due to direct physical impact and chemical reactions caused by rapid guano decomposition. In the vegetated S2 site, the snow pack lasted longer, showing the highest mean minimum temperature and larger thermal insulation, as well as larger FDD than those found in the bare soil of the active rookery (S1), and lower n-F, due to greater thermal insulation. Penguins played a significant role in changing the active layer depth and thermal regime, and represent a neglected actor on the ground thermal regime in Antarctic terrestrial environments.
•We studied the influence of penguins on soil temperature and dynamics of active layer.•Penguins have a marked role in changing active layer depth and thermal regime.•The permafrost is important to control of physical reactions ground.•The Freezing Degree Days, Thawing Degree Days and the N factor index were calculated.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
A promising antitumor xanthone derivative was optimized following a multidimensional approach that involved the synthesis of 17 analogues, the study of their lipophilicity and solubility, and the ...evaluation of their growth inhibitory activity on four human tumor cell lines. A new synthetic route for the hit xanthone derivative was also developed and applied for the synthesis of its analogues. Among the used cell lines, the HL-60 showed to be in general more sensitive to the compounds tested, with the most potent compound having a GI50 of 5.1μM, lower than the hit compound. Lipophilicity was evaluated by the partition coefficient (Kp) of a solute between buffer and two membrane models, namely liposomes and micelles. The compounds showed a logKp between 3 and 5 and the two membrane models showed a good correlation (r2=0.916) between each other. Studies concerning relationship between solubility and structure were developed for the hit compound and 5 of its analogues.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
MamMiBase, the mammalian mitochondrial genome database, is a relational database of complete mitochondrial genome sequences of mammalian species. The database is useful for phylogenetic analysis, ...since it allows a ready retrieval of nucleotide and aminoacid individual alignments, in three different formats (NEXUS for PAUP program, for MEGA program and for PHYLIP program) of the 13 protein coding mitochondrial genes. The user may download the sequences that are useful for him/her based on their parameters values, such as sequence length, p-distances, base content, transition transversion ratio, gamma, which are also given by MamMiBase. A simple phylogenetic tree (neighbor-joining tree with Jukes Cantor distance) is also available for download, useful for parameter calculations and other simple tasks. Availability: MamMiBase is available at http://www.mammibase.lncc.br Contact: atrv@lncc.br
The semiarid region of Brazil consists of a great variety of landscapes, soils and vegetation forms, with complex interrelations. In order to better understand this interplay, we posed two questions: ...Are there greater pedological similarities among the different landforms of the same catena or among the same landforms from different catenas? Which soil attributes could be the most important to segregate communities of plants? We sampled soils and vegetation on different landforms in four different catenas and performed NMS (non-metric multidimensional scaling) and ANOVA (analysis of variance) to address the first question; also, we carried another NMS following GLM (general linear model regression) to answer the second question. The first NMS indicated the existence of a fertility gradient, grouping communities in relation to similar landforms, confirmed by ANOVA. The second NMS indicated the same gradient whereas the GLM showed that is controlled by aluminum saturation, sodium saturation, phosphorous and sand content. One extreme of the gradient has uplands associated with cerrado vegetation forms whereas the other extreme slopes were associated with dry forests. The lowlands associated with dry forest represent the central position of the fertility gradient. In general, soils at similar landforms showed greater pedological similarity, and their physico-chemical attributes determined the formation and structure of vegetation. This similarity across the same landform refers to the comparable soil formation at each landform and soil age at landscape scale. The characteristics of the vegetation and soils in the Brazilian southern semiarid region indicated a previously wetter climate, during which deep weathered latosols (oxisols) were formed and remain as relics in the present semiarid.
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BFBNIB, DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NMLJ, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
A series of experiments was conducted to investigate the locomotor effects of local injections of ethanol and the ethanol metabolite, acetaldehyde, into substantia nigra pars reticulata (SNr). ...Infusions of ethanol into SNr resulted in a dose-related increase in locomotor activity, with maximal effects at a dose of 1.4 micromol. Ethanol injected into a control site dorsal to substantia nigra failed to stimulate locomotion, and another inactive site was identified in brainstem areas posterior to substantia nigra. The locomotor effects of intranigral ethanol (1.4 micromol) were reduced by coadministration of 10 mg/kg sodium azide, a catalase inhibitor that acts to reduce the metabolism of ethanol into acetaldehyde in the brain. SNr infusions of acetaldehyde, which is the first metabolite of ethanol, also increased locomotion. Taken together, these results indicate that SNr is one of the sites at which ethanol and acetaldehyde may be acting to induce locomotor activity. These results are consistent with the hypothesis that acetaldehyde is a centrally active metabolite of ethanol, and provide further support for the idea that catalase activity is a critical step in the regulation of ethanol-induced motor activity. These studies have implications for understanding the brain mechanisms involved in mediating the ascending limb of the biphasic dose-response curve for the effect of ethanol on locomotor activity.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The aim of this study was to evaluate butaphosphan and cyanocobalamin effects on the production of oocytes in vivo and in vitro embryo production (IVP) during an ovum pick up (OPU) protocol. ...Thirty-six cows were homogeneously divided into two groups. The butaphosphan and cyanocobalamin group (CAT, n = 17), received 4500 mg of butaphosphan and 2.25 mg of cyanocobalamin and the control group (CONT, n = 19) received placebo (NaCl 0.9%). Treatment was performed at 14, 9, and 5 d prior the follicular aspiration (FA) sessions and each cow was subjected to three sessions of OPU and IVP. CAT group showed high (P < 0.05) number of aspirated follicles between 3 and 6 mm and number of oocytes grade 2 and a tendency (P = 0.10) of total number of follicles aspired. No difference (P > 0.05) was found for the number of different sizes of follicles aspired, retrieved oocytes, recovery rate, viable oocytes, blastocysts, and total viable blastocysts. In conclusion, successive butaphosphan and cyanocobalamin administrations can potentially increase IVP and quality in Jersey cows during a OPU protocol.
The Role of Acetaldehyde in the Central Effects of Ethanol Quertemont, Etienne; Grant, Kathleen A.; Correa, Mercè ...
Alcoholism, clinical and experimental research,
02/2005, Volume:
29, Issue:
2
Journal Article, Conference Proceeding
Peer reviewed
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
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