Variability of apparently homogeneous soilscapes in São Paulo state, Brazil: II. quality of soil maps

The quality of semi-detailed (scale 1:100.000) soil maps and the utility of a taxonomically based legend were assessed by studying 33 apparently homogeneous fields with strongly weathered soils in two regions in São Paulo State: Araras and Assis. An independent data set of 395 auger sites was used to determine purity of soil mapping units and analysis of variance within and between mapping units and soil classification units. Twenty three soil profiles were studied in detail. The studied soil maps have a high purity for some legend criteria, such as B horizon type (> 90%) and soil texture class (> 80%). The purity for the "trophic character" (eutrophic, dystrophic, allic) was only 55% in Assis. It was 88% in Araras, where many soil units had been mapped as associations. In both regions, the base status of clay-textured soils was generally better than suggested by the maps. Analysis of variance showed that mapping was successful for "durable" soil characteristics such as clay content (> 80% of variance explained) and cation exchange capacity (≥ 50% of variance explained) of 0-20 and 60-80 cm layers. For soil characteristics that are easily modified by management, such as base saturation of the 0-20 cm layer, the maps had explained very little (< 15%) of the total variance in the study areas. Intermediate results were obtained for base saturation of the 60-80 cm layer (56% in Assis; 42% in Araras). Variance explained by taxonomic groupings that formed the basis for the legend of the soil maps was similar to, often even smaller than, variance explained by mapping units. The conclusion is that map boundaries have been very carefully located, but descriptions of mapping units could be improved. In future mappings, this could possibly be done at low cost by (a) bulk sampling to remove short range variation and enhance visualization of spatial patterns at distances > 100 m; (b) taking advantage of correlations between easily measured soil characteristics and chemical soil properties and, (c) unbending the link between legend criteria and a taxonomic system. The maps are well suited to obtain an impression of land suitability for high-input farming. Additional field work and data on former land use/management are necessary for the evaluation of chemical properties of surface horizons.

Estimativa da acidez potencial pelo pH SMP em solos do semi-árido do Nordeste brasileiro

Neste estudo avaliou-se a relação entre o teor de H + Al e o pH SMP, visando estabelecer uma equação para estimar a acidez potencial de solos do Semi-Árido do Nordeste Brasileiro. As análises dos teores de H + Al e dos valores de pH SMP foram realizadas em 81 amostras de solo, variando os teores de carbono de 1,8 a 35,6 g kg-1 e os de argila de 60 a 590 g kg-1. Os resultados demonstraram que a acidez potencial dessas amostras de solo, expressa em mmol c dm-3, pode ser estimada pelo valor do pH em solução tampão SMP, por meio da equação de regressão: H + Al = 31,521 (pH SMP)² - 451,61 pH SMP + 1625,3 (R² = 0,87**).

Diet and breeding success of long-eared owls in a semi-arid environment

Only a few studies, and mostly in temperate climates in Europe, have examined the breeding and diet of long-eared owls (Asia otus) compared to studies of cavity-breeding owls, possibly because of the difficulties in reaching the nests of the former. Here we studied a population of long-eared owls, monitoring the diet of breeding owls and that of owls at a communal roost, every two to three months during 2006 -2009, in a semi-arid region in Israel. It was found that the studied owls produced more young than in most countries in Europe. Diet was not associated with breeding parameters of the owls, whereas laying date was negatively correlated with both clutch size and number of nestlings. We found that more social voles (Microtus socialis) and fewer birds and house mice (Mus musculus) made up the diet at nests than that of adults at the roosts. The diet and breeding of long-eared owls in Israel differ from that in Europe, with birds and mice comprising an important part of the diet, in addition to voles.

Effects of aerobic fitness on oxygen uptake kinetics in heavy intensity swimming.

This study aimed to characterise both the [Formula: see text] kinetics within constant heavy-intensity swimming exercise, and to assess the relationships between [Formula: see text] kinetics and other parameters of aerobic fitness, in well-trained swimmers. On separate days, 21 male swimmers completed: (1) an incremental swimming test to determine their maximal oxygen uptake [Formula: see text], first ventilatory threshold (VT), and the velocity associated with [Formula: see text] [Formula: see text] and (2) two square-wave transitions from rest to heavy-intensity exercise, to determine their [Formula: see text] kinetics. All the tests involved breath-by-breath analysis of freestyle swimming using a swimming snorkel. [Formula: see text] kinetics was modelled with two exponential functions. The mean values for the incremental test were 56.0 ± 6.0 ml min(-1) kg(-1), 1.45 ± 0.08 m s(-1); and 42.1 ± 5.7 ml min(-1) kg(-1) for [Formula: see text], [Formula: see text] and VT, respectively. For the square-wave transition, the time constant of the primary phase (τ(p)) averaged 17.3 ± 5.4 s and the relevant slow component (A'(sc)) averaged 4.8 ± 2.9 ml min(-1) kg(-1) [representing 8.9% of the end-exercise [Formula: see text] (%A'(sc))]. τ(p) was correlated with [Formula: see text] (r = -0.55, P = 0.01), but not with either [Formula: see text] (r = 0.05, ns) or VT (r = 0.14, ns). The %A'(sc) did not correlate with either [Formula: see text] (r = -0.14, ns) or [Formula: see text] (r = 0.06, ns), but was inversely related with VT (r = -0.61, P < 0.01). This study was the first to describe the [Formula: see text] kinetics in heavy-intensity swimming using specific swimming exercise and appropriate methods. As has been demonstrated in cycling, faster [Formula: see text] kinetics allow higher aerobic power outputs to be attained. The slow component seems to be reduced in swimmers with higher ventilatory thresholds.

Tomografia computadorizada na avaliação da densidade de um solo do semi-árido brasileiro

A densidade do solo de amostras indeformadas foi determinada por meio das técnicas de tomografia computadorizada e do torrão impermeabilizado, visando à identificação de processos de compactação do solo e a comparação de métodos. A pesquisa também visou auxiliar um levantamento pedológico elaborado com fins de classificação de terras para irrigação. As amostras de solo foram coletadas da região semi-árida de Petrolina (PE), ao longo de perfis do solo, da superfície até 1 m de profundidade, em camadas de 0,1 m e em duas áreas distintas quanto à sua ocupação vegetal e manejo: (1) vegetação natural (caatinga); (2) área cultivada e irrigada por pivô central. As tomografias foram realizadas com um tomógrafo de primeira geração, constituído por uma fonte de radiação gama de 137Cs e um detetor cintilador de NaI(Tl), com eletrônica padrão de espectrometria gama e sistema de movimentação de amostra controlados por uma interface específica acoplada a um microcomputador. Na área de caatinga, os resultados evidenciam a ocorrência de um adensamento do solo em camadas mais profundas, abaixo de 0,4 m, bem como de uma camada adensada e, ou, compactada entre aproximadamente 0 e 0,4 m, na área cultivada com pivô central, possivelmente em virtude da ação de máquinas e implementos utilizados no preparo e cultivo do solo.

Defining substance use disorders: do we really need more than heavy use?

AIMS: The aim of the study was to explore whether the concept of heavy substance use over time can be used as definition of substance use disorder. METHODS: Narrative review. RESULTS: Heavy use over time clearly underlies the neurobiological changes associated with current thinking of substance use disorders. In addition, there is evidence that heavy use over time can explain the majority of social problems and of burden of disease (morbidity and mortality). A definition of substance use disorders via heavy use over time would avoid some of the problems of current conceptualizations, for instance the cultural specificity of concepts such as loss of control. Finally, stressing the continuum of use may avoid the high level of stigmatization currently associated with substance use disorders. CONCLUSION: 'Heavy substance use over time' seems to be a definition of substance use disorders in line with results of basic research and epidemiology. Additionally, it reduces stigmatization. This approach should thus be further explored.

Caracterização micromorfológica e considerações sobre a gênese de solos de tabuleiro do semi-árido do Brasil

Detalhadas investigações macro e, especialmente, micromorfológicas foram realizadas em dois perfis de Argissolo Amarelo e um de Planossolo de uma superfície geomorfológica tabular, pertencente aos Tabuleiros Sertanejos (Interioranos) na bacia hidrográfica do médio São Francisco em Petrolina, Pernambuco. O objetivo do estudo foi caracterizar micromorfologicamente os solos, procurando fornecer subsídios para o entendimento da pedogênese, como uma forma de entender a diversidade dos solos na paisagem. Os resultados indicam que os três perfis foram derivados de sedimentos pós-cretáceos, em intensa mistura com resíduos de rochas cristalinas do Pré-Cambriano, provavelmente, ainda, influenciados por materiais de antigos terraços fluviais do rio São Francisco. As diferenciações entre os três perfis estão relacionadas com a heterogeneidade resultante da mistura desses materiais de origem, mas, principalmente, com o posicionamento dos solos no relevo, gerando condições diferenciadas de drenagem. Concreções de ferro herdadas do material de origem, sofreram degradações e se transfomaram em mosqueamentos plínticos, e, posteriormente, foram dissipadas no solo, eluviação/iluviação, ou perdas do sistema, parece ser um dos processos envolvidos na pedogênese.

Role of high normal gamma-glutamyltransferase level in identifying heavy alcohol use in young men.

The objective of the current study was to determine the predictive value of high normal gamma-glutamyltransferase (GGT) level as an indication of heavy drinking in young men. In a sample of 577 men attending a one-day army recruitment process mandatory for all Swiss men at age 19 years, GGT level was evaluated as the dependent variable for each of eight dichotomous classifications of individuals on the basis of meeting cut-off criteria for five indexes of alcohol use, two indexes of alcohol-related problems, and one index of body mass. The sensitivity, specificity, and predictive values of GGT level in identifying subjects as either heavy drinkers or being overweight were determined. Compared with findings for their counterparts, GGT level was higher in subjects reporting consumption of more than 14 drinks per week (20.5 +/- 7.81 vs. 18.9 +/- 7.60, P <.05), in those reporting being drunk at least once during the past 30 days (20.3 +/- 7.80 vs. 18.3 +/- 7.43, P <.001), and in individuals with body mass indexes >or=25 kg/m(2) (25.8 +/- 10.84 vs. 18.3 +/- 6.59, P <.001). At a GGT level cut-off of 20 U/l, the sensitivity, specificity, and positive and negative predictive values of either being a heavy drinker or overweight were 48.2%, 70.2%, 67.7%, and 51.2%, respectively. Exclusion of subjects with body mass indexes of >or=25 kg/m(2) revealed similar results. High normal GGT level in young men is indicative of heavy alcohol use or being overweight; when present, subjects should be screened further for potential concomitant drinking problems.

Frações de fósforo após extrações sucessivas com resina e incubação, em Latossolos e Luvissolos do semi-árido de Pernambuco

A reposição do P mais lábil pelas frações menos lábeis do solo foi avaliada após dez extrações sucessivas com resina e incubação, durante quatro meses, em amostras dos horizontes A, BA e Bw de Latossolos e A e Bt de Luvissolos, coletadas do terço superior, médio e inferior de três toposseqüências de cada classe, fazendo-se um fracionamento seqüencial de P antes das extrações sucessivas e depois da incubação. O fracionamento foi feito com resina, NaHCO3 (fração orgânica e inorgânica), NaOH (fração orgânica e inorgânica), H2SO4 e uma digestão com H2SO4 e H2O2. Não houve diferenças significativas entre posições na encosta. As dez extrações sucessivas retiraram duas a cinco vezes mais P que a primeira extração nos Latossolos e duas a nove vezes nos Luvissolos. As últimas extrações mostraram estabilidade em torno de 1 mg kg-1 em todos os solos e horizontes. Após a incubação, o P-resina recuperou 20-30 % do seu valor inicial nos horizontes A (1,8 e 3,3 mg kg-1) e 50-90 % nos subsuperficiais (1,1 e 1,2 mg kg-1), para Latossolos e Luvissolos, respectivamente. As demais frações também se alteraram, mais nos Luvissolos e nos horizontes superficiais. Entretanto, as frações mais estáveis permaneceram com maiores teores. As frações com maiores decréscimos foram P-NaOH, nos Latossolos, e P-H2SO4, seguido de P-NaOH, nos Luvissolos, indicando serem elas as principais frações no processo de reposição do P disponível, nestes solos de semi-árido.

Análise espaço-temporal do uso da terra em parte do semi-árido cearense

A cobertura vegetal exerce papel imprescindível à proteção e conservação dos recursos naturais, principalmente no que diz respeito aos solos. Este estudo teve como objetivo avaliar e analisar a dimensão espacial e temporal da ação antrópica na cobertura vegetal de parte do semi-árido cearense, utilizando imagens LANDSAT TM-5, de 1985 e 1994, e técnicas de geoprocessamento, para verificar a hipótese de que a degradação ambiental vem sendo intensificada. Foram confeccionadas cartas de vegetação, uso da terra, solos e hidrografia, obtendo-se cartas de sobreposição, por meio das quais se constatou o aumento de áreas degradadas nas diferentes unidades fitoecológicas. No período de uma década, comprovou-se o processo progressivo da degradação nas áreas dos municípios de Independência, Pedra Branca, Mombaça e Tauá, tendo as áreas do município de Pedra Branca apresentado menor degradação. A unidade fitoecológica mais degradada, dentre as estudadas, foi a Caatinga Arbórea Aberta, desencadeando processos de degradação e transformação das unidades circunvizinhas. Grande parte da área foi atingida por processos de degradação ambiental, com forte pauperização da biodiversidade, acompanhados por um rebaixamento geral das formações vegetais.

Semi-purity of tempered Deligne cohomology

In this paper we define the formal and tempered Deligne cohomology groups, that are obtained by applying the Deligne complex functor to the complexes of formal differential forms and tempered currents respectively. We then prove the existence of a duality between them, a vanishing theorem for the former and a semipurity property for the latter. The motivation of these results comes from the study of covariant arithmetic Chow groups. The semipurity property of tempered Deligne cohomology implies, in particular, that several definitions of covariant arithmetic Chow groups agree for projective arithmetic varieties.

Decomposição de estercos dispostos em diferentes profundidades em área degradada no semi-árido da Paraíba

Este estudo objetivou avaliar a velocidade de decomposição de estercos dispostos em diferentes profundidades. Utilizaram-se estercos asinino, bovino, caprino e ovino, que foram secos em estufa a ± 65 ºC, acondicionando-se 20 g de cada um em sacolas de náilon, sendo dispostos superficialmente e enterrados a 10,0 cm de profundidade. Mensalmente, coletou-se uma sacola/parcela, sendo o material limpo, seco em estufa e pesado para determinar a percentagem de perda em relação ao peso inicial, avaliando-se, assim, a decomposição. A decomposição foi lenta nos trinta dias iniciais, ficando nas sacolas de náilon mais ou menos 95 % do peso inicial dos estercos. Evidencia-se que a taxa de decomposição dos estercos foi fortemente influenciada pela pluviosidade ocorrida no período experimental. O esterco asinino foi mais resistente à decomposição, sendo a velocidade de decomposição mais acentuada nos estercos dispostos em 10,0 cm de profundidade.

An Efficient Segmentation Method for Ultrasound Images based on a Semi-supervised Approach and Patch-based Features

Segmenting ultrasound images is a challenging problemwhere standard unsupervised segmentation methods such asthe well-known Chan-Vese method fail. We propose in thispaper an efficient segmentation method for this class ofimages. Our proposed algorithm is based on asemi-supervised approach (user labels) and the use ofimage patches as data features. We also consider thePearson distance between patches, which has been shown tobe robust w.r.t speckle noise present in ultrasoundimages. Our results on phantom and clinical data show avery high similarity agreement with the ground truthprovided by a medical expert.

A methodology for the classification of convective structures using meteorological radar: Application to heavy rainfall events on the Mediterranean coast of the Iberian Peninsula

During the period 1996-2000, forty-three heavy rainfall events have been detected in the Internal Basins of Catalonia (Northeastern of Spain). Most of these events caused floods and serious damage. This high number leads to the need for a methodology to classify them, on the basis of their surface rainfall distribution, their internal organization and their physical features. The aim of this paper is to show a methodology to analyze systematically the convective structures responsible of those heavy rainfall events on the basis of the information supplied by the meteorological radar. The proposed methodology is as follows. Firstly, the rainfall intensity and the surface rainfall pattern are analyzed on the basis of the raingauge data. Secondly, the convective structures at the lowest level are identified and characterized by using a 2-D algorithm, and the convective cells are identified by using a 3-D procedure that looks for the reflectivity cores in every radar volume. Thirdly, the convective cells (3-D) are associated with the 2-D structures (convective rainfall areas). This methodology has been applied to the 43 heavy rainfall events using the meteorological radar located near Barcelona and the SAIH automatic raingauge network.