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1.
Neotrop Entomol ; 49(1): 24-32, 2020 Feb.
Article in English | MEDLINE | ID: mdl-31522364

ABSTRACT

Although most species distribution modeling (SDMs) are constructed at the species level, an appreciation of evolutionary processes has led to modeling above this level. In view of the difficulty in estimating the impacts of human actions on rare or deficient data species, we proposed a new approach to vulnerability assessment based on concepts already well established in the literature (ecological niche, niche conservatism, and extinction thresholds). We used distribution modeling to predict where species of the genus Phyllocycla (Calvert 1948) are most vulnerable to local extinctions and how the implementation of planned anthropic activities by the Brazilian government may modify the potential distribution of the genus in Brazil. We chose that genus because its conservation status is little known, especially due to the data gap about its geographical distribution. We proposed modeling the whole genus and used the niche conservatism theory to justify our methods. The anthropic activities considered in our analysis were agriculture and livestock, rural settlements, energy production installations, transportation, oil extraction, mining, and urbanization. We found that only 55.3% of the original potential distribution of Phyllocycla in Brazil remains available. The area compromised by anthropic activities comprises mainly the Cerrado and Atlantic Forest biomes, with less impact on the Amazon. However, with the implementation of activities planned by the Brazilian government, it is possible that an additional 13.6% of this area will be unavailable to species of Phyllocycla, especially in the Amazon, where interest in mining and the implementation of new hydroelectric production have increased.


Subject(s)
Conservation of Natural Resources , Ecosystem , Extinction, Biological , Odonata , Agriculture , Animals , Brazil , Forests , Government , Human Activities , Humans , Mining , Models, Theoretical , Oil and Gas Industry , Urbanization
2.
Aust Dent J ; 58(4): 478-82, 2013 Dec.
Article in English | MEDLINE | ID: mdl-24320905

ABSTRACT

BACKGROUND: The aim of this study was to investigate the effect of arginine and fluoride on the reduction of erosive wear. METHODS: Bovine enamel blocks were randomly allocated into four groups (n = 20) and exposed to: ESPR group (8% arginine, 1450 ppm sodium monofluorophosphate, calcium carbonate and titanium dioxide); ESen group (1450 ppm sodium monofluorophosphate, 5% potassium citrate); positive control PC group (1500 ppm sodium monofluorophosphate) and negative control NC group (water). The samples were submitted to six alternating cycles of demineralization-remineralization (cola, 10 minutes; artificial saliva, 1 hour, respectively). Before and between cyclic demineralization and remineralization, blocks were treated with slurries of the respective toothpastes or water (1 minute). Erosive tissue loss was analysed by microhardness and profilometry. Data were analysed by ANOVA and Tukey tests for individual comparisons among the groups (p < 0.05). RESULTS: In microhardness, the ESPR (217.46 ± 55.45) group was significantly better than the other treatment groups (PC = 302.76 ± 96.10; ESen = 315.56 ± 74.56; p < 0.001). The ESPR group showed a similar loss to NC group (NC = 210.8 ± 49.98; p = 0.991). The mean erosion depth (+/- SE, µm) was detected between NC (14.37 ± 1.72) and dentifrices tested (ESPR (4.11 ± 1.34), ESen group (7.64 ± 1.61) and PC (8.20 ± 2.19) (p = 0.000). CONCLUSIONS: From the results of the present study, the effectiveness of Sensitive Pro Relief in the prevention of erosive surface loss seems to be attributed to the possible effect of the arginine associated with fluoride.


Subject(s)
Arginine/pharmacology , Fluorides/pharmacology , Phosphates/pharmacology , Tooth Erosion/prevention & control , Toothpastes/pharmacology , Animals , Calcium Carbonate/pharmacology , Cattle , Dental Enamel/drug effects , Hardness , Potassium Citrate/pharmacology , Random Allocation , Saliva, Artificial , Sodium Fluoride/pharmacology , Tooth Remineralization/methods , Toothpastes/chemistry
3.
Braz J Med Biol Res ; 41(2): 176-9, 2008 Feb.
Article in English | MEDLINE | ID: mdl-18297198

ABSTRACT

Serum hormone levels were compared between captive and free-living maned wolves and seasonal variations of sex hormones were studied. Blood samples were collected from 16 male and 26 female adult animals from Brazilian zoos, and from 30 male and 24 female free-living adults to determine serum progesterone and testosterone by radioimmunoassay. Serum testosterone concentrations varied (P < 0.05) across seasons for 16 captive males, being higher in autumn (2184.7 +/- 355.1 pg/mL) than in summer (1080.7 +/- 205.4 pg/mL), winter (1270.1 +/- 276.6 pg/mL) and spring (963.9 +/- 248.1 pg/mL), although they did not differ between summer, winter and spring. Testosterone concentration of 30 free-living males differed (P < 0.05) between autumn (824.1 +/- 512.2 pg/mL), winter (14.4 +/- 8.0 pg/mL) and spring (151.9 +/- 90.5 pg/mL). Comparison between captive and free-living animals showed no difference in autumn (P > 0.05). Sixteen captive males showed higher testosterone concentration during winter and spring compared with 30 free-living animals (P < 0.05). Progesterone concentration varied among seasons in 26 captive females (P < 0.05), being higher in autumn (15.3 +/- 3.1 ng/mL) than in summer (6.6 +/- 1.5 ng/mL), winter (5.3 +/- 3.1 ng/mL) and spring (4.3 +/- 0.7 ng/mL). Progesterone concentration of 24 free-living females varied between autumn (17.1 +/- 6.0 ng/mL) and winter (1.7 +/- 0.3 ng/mL) (P < 0.05), but we could not obtain data for spring or summer. No difference in progesterone levels was observed between captive and free-living females in autumn and winter.


Subject(s)
Animals, Zoo/blood , Progesterone/blood , Testosterone/blood , Wolves/blood , Animals , Female , Male , Radioimmunoassay , Seasons
4.
Braz. j. med. biol. res ; 41(2): 176-179, Feb. 2008. graf
Article in English | LILACS | ID: lil-474766

ABSTRACT

Serum hormone levels were compared between captive and free-living maned wolves and seasonal variations of sex hormones were studied. Blood samples were collected from 16 male and 26 female adult animals from Brazilian zoos, and from 30 male and 24 female free-living adults to determine serum progesterone and testosterone by radioimmunoassay. Serum testosterone concentrations varied (P < 0.05) across seasons for 16 captive males, being higher in autumn (2184.7 ± 355.1 pg/mL) than in summer (1080.7 ± 205.4 pg/mL), winter (1270.1 ± 276.6 pg/mL) and spring (963.9 ± 248.1 pg/mL), although they did not differ between summer, winter and spring. Testosterone concentration of 30 free-living males differed (P < 0.05) between autumn (824.1 ± 512.2 pg/mL), winter (14.4 ± 8.0 pg/mL) and spring (151.9 ± 90.5 pg/mL). Comparison between captive and free-living animals showed no difference in autumn (P > 0.05). Sixteen captive males showed higher testosterone concentration during winter and spring compared with 30 free-living animals (P < 0.05). Progesterone concentration varied among seasons in 26 captive females (P < 0.05), being higher in autumn (15.3 ± 3.1 ng/mL) than in summer (6.6 ± 1.5 ng/mL), winter (5.3 ± 3.1 ng/mL) and spring (4.3 ± 0.7 ng/mL). Progesterone concentration of 24 free-living females varied between autumn (17.1 ± 6.0 ng/mL) and winter (1.7 ± 0.3 ng/mL) (P < 0.05), but we could not obtain data for spring or summer. No difference in progesterone levels was observed between captive and free-living females in autumn and winter.


Subject(s)
Animals , Female , Male , Animals, Zoo/blood , Progesterone/blood , Testosterone/blood , Wolves/blood , Radioimmunoassay , Seasons
5.
Braz J Biol ; 66(3): 873-81, 2006 Aug.
Article in English | MEDLINE | ID: mdl-17119835

ABSTRACT

Although in most recent broad-scale analyses, diversity is measured by counting the number of species in a given area or spatial unity (species richness), a 'top-down' approach has been used sometimes, counting higher-taxon (genera, family) instead of species with some advantages. However, this higher-taxon approach is quite empirical and the cut-off level is usually arbitrarily defined. In this work, we show that the higher-taxon approach could be theoretically linked with models of phenotypic diversification by means of phylogenetic autocorrelation analysis in such a way that the taxonomic (or phylogenetic) rank to be used could not be necessarily arbitrary. This rank expresses past time in which taxa became independent for a given phenotypic trait or for the evolution of average phenotypes across different traits. We illustrated the approach by evaluating phylogenetic patches for 23 morphological, ecological and behavioural characters in New World terrestrial Carnivora. The higher-taxon counts at 18.8 mya (S(L)) defined by phylogenetic correlograms are highly correlated with species richness (r = 0.899; P < 0.001 with ca. 13 degrees of freedom by taking spatial autocorrelation into account). However, S(L) in North America is usually larger than in South America. Thus, although there are more species in South and Central America, the fast recent diversification that occurred in this region generated species that are "redundant" in relation to lineages that were present at 18.8 my. BP. Therefore, the number of lineages can be comparatively used as a measure of evolutionary diversity under a given model of phenotypic divergence among lower taxonomic units.


Subject(s)
Biodiversity , Biological Evolution , Carnivora/genetics , Phenotype , Phylogeny , Animals , Carnivora/classification , Models, Genetic
6.
Braz. j. biol ; 66(3): 873-881, Aug. 2006. graf, mapas, tab
Article in English, Portuguese | LILACS | ID: lil-435628

ABSTRACT

Although in most recent broad-scale analyses, diversity is measured by counting the number of species in a given area or spatial unity (species richness), a `top-down' approach has been used sometimes, counting higher-taxon (genera, family) instead of species with some advantages. However, this higher-taxon approach is quite empirical and the cut-off level is usually arbitrarily defined. In this work, we show that the higher-taxon approach could be theoretically linked with models of phenotypic diversification by means of phylogenetic autocorrelation analysis in such a way that the taxonomic (or phylogenetic) rank to be used could not be necessarily arbitrary. This rank expresses past time in which taxa became independent for a given phenotypic trait or for the evolution of average phenotypes across different traits. We illustrated the approach by evaluating phylogenetic patches for 23 morphological, ecological and behavioural characters in New World terrestrial Carnivora. The higher-taxon counts at 18.8 mya (S L) defined by phylogenetic correlograms are highly correlated with species richness (r = 0.899; P < 0.001 with ca. 13 degrees of freedom by taking spatial autocorrelation into account). However, S L in North America is usually larger than in South America. Thus, although there are more species in South and Central America, the fast recent diversification that occurred in this region generated species that are "redundant" in relation to lineages that were present at 18.8 my. BP. Therefore, the number of lineages can be comparatively used as a measure of evolutionary diversity under a given model of phenotypic divergence among lower taxonomic units.


Embora as análises da biodiversidade em escalas geográficas amplas sejam normalmente realizadas em nível das espécies, alguns trabalhos recentes têm utilizado contagens de categorias taxonômicas mais elevadas, com algumas vantagens. Entretanto, essa abordagem é aplicada de forma empírica e o nível hierárquico escolhido (gênero, famílias, etc.) é geralmente arbitrário. Este trabalho, mostra que essa abordagem pode ser ligada teoricamente aos modelos de evolução fenotípica pelos métodos de autocorrelação filogenética. Esse nível da hierarquia deve expressar o tempo passado no qual os taxa analisados se tornam independentes estatisticamente, para o fenótipo. O método proposto foi aplicado para analisar a evolução fenotípica de 23 caracteres morfológicos, ecológicos e comportamentais em espécies de Carnivora do Novo Mundo. A contagem de linhagens há 18,8 milhões de anos atrás, definida pelos correlogramas filogenéticos, foi altamente correlacionada com a riqueza de espécies (r = 0,899; P < 0,001 com 13 graus de liberdade, levando em consideração a autocorrelação espacial). O número de linhagens foi maior na América do Norte, de modo que embora haja mais espécies na região tropical, estas representam eventos recentes de diversificação, com espécies redundantes em relação às linhagens que existiam há 18,8 milhões de anos atrás. O número de linhagens definido por autocorrelação pode ser utilizado como uma medida de diversidade evolutiva sob um dado modelo de divergência fenotípica.


Subject(s)
Animals , Biodiversity , Biological Evolution , Carnivora/genetics , Phenotype , Phylogeny , Carnivora/classification , Models, Genetic
7.
Braz. j. biol ; 62(3): 437-444, Aug. 2002. graf
Article in English | LILACS | ID: lil-326214

ABSTRACT

Rapoport effect predicts that species geographic range sizes will increase toward higher latitudes, probably reflecting adaptations to extreme climatic conditions that increase species tolerance. Recently, studies about spatial patterns in species richness and geographic range size may be associated with the geometry of species' ranges. In this context, null models can be used to search for the causal mechanisms associated with these patterns. In this paper, we analyzed Rapoport effect using a null model to evaluate how phylogenetic structure and geometric constraints simultaneously affect latitudinal extents of 40 species of South American terrestrial Carnivora. The latitudinal extents of Carnivora tended to decrease toward Southern latitudes, in the opposite direction expected under a simple Rapoport effect, but in accordance to geometric expectations of position of midpoints in the continent. Using 5000 simulations, it was possible to show that the null regression coefficients of latitudinal extents against midpoints are positively biased, reflecting the geometric constraints in the latitudinal extents. The results were equivalent in phylogenetic and non-phylogenetic analyses. The observed regression coefficient was significantly smaller (line is less inclined) than expected by chance alone, demonstrating that the geometric constraints in the latitudinal extents exist even after controlling for phylogenetic structure in data using eigenvector regressions. This suggests that the "spirit" of Rapoport effect (sensu Lyons & Willig, 1997) could be maintained, i.e., that latitudinal extents in Southern region of the continent are relatively larger than those in Northern regions, even after controlling for phylogenetic effects


Subject(s)
Animals , Adaptation, Physiological , Carnivora , Geography , Models, Biological , Phylogeny , Population Dynamics
8.
Braz J Biol ; 62(3): 437-44, 2002 Aug.
Article in English | MEDLINE | ID: mdl-12530179

ABSTRACT

Rapoport effect predicts that species geographic range sizes will increase toward higher latitudes, probably reflecting adaptations to extreme climatic conditions that increase species tolerance. Recently, studies about spatial patterns in species richness and geographic range size may be associated with the geometry of species' ranges. In this context, null models can be used to search for the causal mechanisms associated with these patterns. In this paper, we analyzed Rapoport effect using a null model to evaluate how phylogenetic structure and geometric constraints simultaneously affect latitudinal extents of 40 species of South American terrestrial Carnivora. The latitudinal extents of Carnivora tended to decrease toward Southern latitudes, in the opposite direction expected under a simple Rapoport effect, but in accordance to geometric expectations of position of midpoints in the continent. Using 5000 simulations, it was possible to show that the null regression coefficients of latitudinal extents against midpoints are positively biased, reflecting the geometric constraints in the latitudinal extents. The results were equivalent in phylogenetic and non-phylogenetic analyses. The observed regression coefficient was significantly smaller (line is less inclined) than expected by chance alone, demonstrating that the geometric constraints in the latitudinal extents exist even after controlling for phylogenetic structure in data using eigenvector regressions. This suggests that the "spirit" of Rapoport effect (sensu Lyons & Willig, 1997) could be maintained, i.e., that latitudinal extents in Southern region of the continent are relatively larger than those in Northern regions, even after controlling for phylogenetic effects.


Subject(s)
Adaptation, Physiological , Carnivora/physiology , Models, Biological , Models, Theoretical , Phylogeny , Animals , Population Dynamics
9.
Midwife Health Visit ; 2(6): 237-40, 1966 Jun.
Article in English | MEDLINE | ID: mdl-5177810

Subject(s)
Nursing , Sex Education
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