Terrane transfer during the Grenville orogeny: tracing the Amazonian ancestry of southern Appalachian basement through Pb and Nd isotopes

Whole rock Pb isotope data can be used to determine the provenance of different blocks within the Rodinia supercontinent, providing a test for paleogeographic reconstructions. Calculated isotopic values for the source region of the Grenville-deformed SW Amazon craton (Rondonia, Brazil), anchored by published U-Pb zircon ages, are compared to those from the Grenville belt of North America and Grenvillian basement inliers in the southern Appalachians. Both the SW Amazon craton and the allochthonous Blue Ridge/Mars Hill terrane are defined by a similar Pb isotopic signature, indicating derivation from an ancient source region with an elevated U/Pb ratio. In contrast, the Grenville Province of Laurentia (extending from Labrador to the Llano Uplift of Texas) is characterized by a source region with a distinctly lower, time-integrated U/Pb ratio. Published U-Pb zircon ages (ca. 1.8 Ga) and Nd model ages (1.4-2.2 Ga) for the Blue Ridge/Mars Hill terrane also suggest an ancient provenance very different from the rest of the adjacent Grenville belt, which is dominated by juvenile 1.3-1.5 Ga rocks. The presence of mature continental material in rocks older than 1.15 Ga in the Blue Ridge/ Mars Hill terrane is consistent with characteristics of basement rocks from the SW Amazon craton. High-grade metamorphism of the Blue Ridge/Mars Hill basement resulted in purging of U, consistent with observations of the rest of the North American Grenville province. In contrast, the Grenvillian metamorphic history of the Amazon appears to have been much more heterogeneous, with both U enrichment and U depletion recorded locally. We propose that the Blue Ridge/ Mars Hill portion of the Appalachian basement is of Amazonian provenance and was transferred to Laurentia during Grenvillian orogenesis after similar to1.15 Ga. The presence of these Amazonian rocks in southeastern Laurentia records the northward passage of the Amazon craton along the Laurentian margin, following the original collision with southernmost Laurentia at ca. 1.2 Ga. (C) 2004 Elsevier B.V. All rights reserved.

FIRE ANT MOUND DENSITIES IN THE UNITED-STATES AND BRAZIL (HYMENOPTERA, FORMICIDAE)

To compare fire ant populations (Solenopsis) in North and South America, we surveyed 102 preselected roadside sites, half in the southeastern United States and half in the state of Mato Grosso do Sul, Brazil. Fire ants were considerably more abundant in the United States. They occurred at more sites (100 versus 70%), in higher densities (170 versus 30 mounds/ha), in larger mounds (27.0 versus 13.8 liters), and they constituted a larger fraction of the local ant community (97 versus 13% of occupied baits). These data are consistent with the hypothesis that North American populations of S. invicta have escaped natural biological control; however, cultural and climatic factors are also likely explanations.

Exotic species of freshwater decapod crustaceans in the state of São Paulo, Brazil: records and possible causes of their introduction

Based on recent surveys of the freshwater decapod fauna, distributional data of five exotic species of freshwater decapod crustaceans for the hydrographic basins of the state of São Paulo are presented, as part of a large initiative for a comprehensive survey of the state's biodiversity (BIOTA-FAPESP Program). These species are the North American crayfish Procambarus clarkii (Girard) (Cambaridae), the crab Dilocarcinus pagei Stimpson (Trichodactylidae) from the Amazon and Paraguay/lower Parana River Basins, and the palaemonid shrimps Macrobrachium rosenbergii (De Man), from the Indo-Pacific region, Macrobrachium amazonicum (Heller) and Macrobrachium jelskii (Miers), both from the Orinoco, Amazon and the Paraguay/lower Parana River Basins. Possible modes by which their introduction might have occurred are commented upon and potential consequences are discussed.

A disease evolution model with uncertain parameters

In this study we consider the SIS epidemiological model (susceptible-infected-susceptible) in which the transmission and recuperation rates are considered fuzzy sets. The concepts of possibility measures and fuzzy expectancy value are used to obtain the basic reproduction value for infected groups with different viral charge.

Case-based system: Indexing and retrieval with fuzzy hypercube

In some applications with case-based system, the attributes available for indexing are better described as linguistic variables instead of receiving numerical treatment. In these applications, the concept of fuzzy hypercube can be applied to give a geometrical interpretation of similarities among cases. This paper presents an approach that uses geometrical properties of fuzzy hypercube space to make indexing and retrieval processes of cases.

Genotype x environment interaction for age at first calving in Brazilian and Colombian Holsteins

The objective was to determine whether there is a genotype x environment interaction for age at first calving (AFC) in Holstein cattle in Brazil and Colombia. Data included 51,239 and 25,569 first-lactation records from Brazil and Colombia, respectively. Of 4230 sires in the data, 530 were North American sires used in both countries. Analyses were done using the REML bi-trait animal model, and AFC was considered as a distinct characteristic in each country. Fixed effects of contemporary group (herd-calving year), sire genetic group, and cow genetic group, and random effects of animal and residual variation were included in the model. Average AFC in Brazil and Colombia were 29.5 ± 4.0 and 32.1 ± 3.5 mo, respectively. Additive and residual genetic components and heritability coefficient for AFC in Brazil were 2.21 mo 2, 9.41 mo 2, and 0.19, respectively, whereas for Colombia, they were 1.02 mo 2, 6.84 mo 2, and 0.13, respectively. The genetic correlation of AFC between Brazil and Colombia was 0.78, indicating differences in ranking of sires consistent with a genotype x environment interaction. Therefore, in countries with differing environments, progeny of Holstein sires may calve at relatively younger or older ages compared with contemporary herdmates in one environment versus another.

Diagnósticos e intervenções de enfermagem aos pacientes em terapia anticoagulante.

Patients under treatment with oral anticoagulants present specific needs for which nursing care plays an important role, especially to prevent complications. The present review was carried out aiming at discussing nursing diagnoses for these patients by using the system of the North American Nursing Diagnoses Association--NANDA. Diagnoses for such patients depict the risk of bleeding and rethrombosis almost always due to the ineffective control of the therapeutic regimen and the deficit in the volume of fluids during active bleeding. Also, nursing interventions and assessment criteria are proposed for such conditions. The authors see the team's preparation to deal with such therapy as relevant for successful assistance.

A new firefly luciferase with bimodal spectrum: Identification of structural determinants of spectral pH-sensitivity in firefly luciferases

Fireflies emit flashes in the green-yellow region of the spectrum for the purpose of sexual attraction. The bioluminescence color is determined by the luciferases. It is well known that the in vitro bioluminescence color of firefly luciferases can be shifted toward the red by lower pH and higher temperature; for this reason they are classified as pH-sensitive luciferases. However, the mechanism and structural origin of pH sensitivity in fireflies remains unknown. Here we report the cloning of a new luciferase from the Brazilian twilight active firefly Macrolampis sp2, which displays an unusual bimodal spectrum. The recombinant luciferase displays a sensitive spectrum with the peak at 569 nm and a shoulder in the red region. Comparison of the bioluminescence spectra of Macrolampis, Photinus and Cratomorphus firefly luciferases shows that the distinct colors are determined by the ratio between green and red emitters under luciferase influence. Comparison of Macrolampis luciferase with the highly similar North American Photinus pyralis luciferase (91%) showed few substitutions potentially involved with the higher spectral sensitivity in Macrolampis luciferase. Site-directed mutagenesis showed that the natural substitution E354N determines the appearance of the shoulder in the red region of Macrolampis luciferase bioluminescence spectrum, helping to identify important interactions and residues involved in the pH-sensing mechanism in firefly luciferases. © 2005 American Society for Photobiology.

Efficacy of hormone therapy with and without methyltestosterone augmentation of venlafaxine in the treatment of postmenopausal depression: A double-blind controlled pilot study

Objective: This study evaluated the augmentation of venlafaxine with hormone therapy in the treatment of postmenopausal depression. The hormones evaluated were estrogen (0.625 mg) in combination with medroxyprogesterone acetate (2.5 mg) and methyltestosterone (2.5 mg). Design: Seventy-two menopausal women (mean age: 53.6 ± 4.27 years) diagnosed with depression (Montgomery-Åsberg Depression Rating Scale [MADRS] scores ≥ 20) were treated with venlafaxine and one of the following hormone therapy combinations, in a double-blind regimen: estrogen + medroxyprogesterone + methyltestosterone (group 1, n = 20); estrogen + medroxyprogesterone acetate (group 2, n = 20); methyltestosterone only (group 3, n = 16); and no hormone therapy (group 4, n = 16). Study duration was 24 weeks. Primary efficacy outcome was remission according to the MADRS, whereas secondary efficacy measures included the Clinical Global Impression (CGI), Blatt-Kupperman Index, and Women's Health Questionnaire (WHQ). Results: Forty-eight patients completed the study. All groups showed significant improvement from baseline. Group 3 demonstrated significant improvement on the MADRS compared with placebo (group 4) at weeks 20 (P = 0.048) and 24 (P = 0.030); effect size 8.04 (0.83; 15.26) (P = 0.029), but also had the highest dropout rate. Groups 1 and 3 had significant CGI improvement rates compared with placebo: 42.23% (P = 0.012) and 44.45% (P = 0.08), respectively. There were no differences in the WHQ or BKI scores among the groups. Conclusions: Methyltestosterone 2.5 mg had the highest effect size compared with placebo, but the high dropout rate prevented its efficacy from being determined. Estrogen plus medroxyprogesterone, combined with methyltestosterone or otherwise, demonstrated a trend toward increased efficacy of venlafaxine. Further larger-scale clinical trials are needed to elucidate the findings of this pilot study. © 2006 by The North American Menopause Society.

Foreign Investment in Latin America and the Caribbean 1999

Includes bibliography