Sr and Nd isotopic geochemistry of the early ultramafic-mafic rocks of the Mako bimodal volcanic belt of the Kedougou-Kenieba inlier (Senegal)

The Mako bimodal volcanic belt of the Kedougou-Kenieba inlier is composed of volcanic basalts and peridotites interbedded by quartzites and limestones intruded by different generations of granitoids. The early volcanic episode of the belt is constituted of submarine basalts with peridotite similar to those of the oceanic abyssal plains. It is intruded by the Badon Kakadian TTG-granitic batholite dated around 2200 Ma. The second volcanic phase is constituted of basaltic, andesitic, and felsitic flows exhibit structures of aerial volcanic rocks. It is intruded by granites dated between 2160 and 2070 Ma. The general pattern of trace element variation of submarine volcanic rocks is consistent with those of basalts from oceanic plateaus which are the modern equivalent of the Archean greenstones belts. The Nd and Sr isotopic systematics typical of juvenile material indicates that the source of these igneous rocks is derived from a depleted mantle source. These results are consistent with the idea of a major accretion within the West African Craton occurring at about 2.1 Ga and corresponding to an important process of mantle-oceanic lithosphere differentiation.

Searching for planar signatures in WMAP

We search for planar deviations of statistical isotropy in the Wilkinson Microwave Anisotropy Probe (WMAP) data by applying a recently introduced angular-planar statistics both to full-sky and to masked temperature maps, including in our analysis the effect of the residual foreground contamination and systematics in the foreground removing process as sources of error. We confirm earlier findings that full-sky maps exhibit anomalies at the planar (l) and angular (l) scales (l; l) = (2; 5); (4; 7); and (6; 8), which seem to be due to unremoved foregrounds since this features are present in the full-sky map but not in the masked maps. On the other hand, our test detects slightly anomalous results at the scales (l; l) = (10; 8) and (2; 9) in the masked maps but not in the full-sky one, indicating that the foreground cleaning procedure (used to generate the full-sky map) could not only be creating false anomalies but also hiding existing ones. We also find a significant trace of an anomaly in the full-sky map at the scale (l; l) = (10; 5), which is still present when we consider galactic cuts of 18.3% and 28.4%. As regards the quadrupole (l = 2), we find a coherent over-modulation over the whole celestial sphere, for all full-sky and cut-sky maps. Overall, our results seem to indicate that current CMB maps derived from WMAP data do not show significant signs of anisotropies, as measured by our angular-planar estimator. However, we have detected a curious coherence of planar modulations at angular scales of the order of the galaxy`s plane, which may be an indication of residual contaminations in the full-and cut-sky maps.

Tectonic fabric revealed by AARM of the proterozoic mafic dike swarm in the Salvador city (Bahia state): Sao Francisco Craton, NE Brazil

Magnetic fabric and rock magnetism studies were performed on 25 unmetamorphosed mafic dikes of the Meso-Late Proterozoic (similar to 1.02 Ga) dike swarm from Salvador (Bahia State, NE Brazil). This area lies in the north-eastern part of the Sao Francisco Craton, which was dominantly formed/reworked during the Transamazonian orogeny (2.14-1.94 Ga). The dikes crop out along the beaches and in quarries around Salvador city, and cut across both amphibolite dikes and granulites. Their widths range from a few centimeters up to 30 m with an average of similar to 4 m, and show two main trends N 140-190 and N 100-120 with vertical dips. Magnetic fabrics were determined using both anisotropy of low-field magnetic susceptibility (AMS) and anisotropy of anhysteretic remanent magnetization (AARM). The magnetic mineralogy was investigated by many experiments including remanent magnetization measurements at variable low temperatures (10-300 K), Mossbauer spectroscopy, high temperature magnetization curves (25-700 degrees C) and scanning electron microscopy (SEM). The rock magnetism study suggests pseudo-single-domain magnetite grains carrying the bulk magnetic susceptibility and AARM fabrics. The magnetite grains found in these dikes are large and we discard the presence of single-domain grains. Its composition is close to stoichiometric with low Ti substitution, and its Verwey transition occurs around 120 K. The main AMS fabric recognized in the swarm is so-called normal, in which the K(max)-K(int) plane is parallel to the dike plane and the magnetic foliation pole K(min)) is perpendicular to it. This fabric is interpreted as due to magma flow, and analysis of the K m inclination permitted to infer that approximately 80% of the dikes were fed by horizontal or sub-horizontal flows (K(max) < 30 degrees). This interpretation is supported by structural field evidence found in five dikes. In addition, based on the plunge of K(max), two mantle sources could be inferred; one of them which fed about 80% of the swarm would be located in the southern part of the region, and the other underlied the Valeria quarry. However, for all dikes the AARM tensors are not coaxial with AMS fabrics and show a magnetic lineation (AARM(max)) oriented to N30-60E, suggesting that magnetite grains were rotated clockwise from dike plane. The orientation of AARM lineation is similar to the orientation of a system of faults in which the Salvador normal fault is the most important. These faults were formed during Cretaceous rifting in the Reconcavo-Tucano-jatoba assemblage that corresponds to an aborted intra-continental rift formed during the opening of the South Atlantic. Therefore, the AARM fabric found for the Salvador dikes is probably tectonic in origin and suggests that the dike swarm was affected by the important tectonic event responsible for the break-up of the Gondwanaland. (C) 2008 Elsevier B.V. All rights reserved.

Note on ""Continuous matter creation and the acceleration of the universe: the growth of density fluctuations""

Recently, de Roany and Pacheco (Gen Relativ Gravit, doi:10.1007/s10714-010-1069-2) performed a Newtonian analysis on the evolution of perturbations for a class of relativistic cosmological models with Creation of Cold Dark Matter (CCDM) proposed by the present authors (Lima et al. in JCAP 1011:027, 2010). In this note we demonstrate that the basic equations adopted in their work do not recover the specific (unperturbed) CCDM model. Unlike to what happens in the original CCDM cosmology, their basic conclusions refer to a decelerating cosmological model in which there is no transition from a decelerating to an accelerating regime as required by SNe type Ia and complementary observations.

A PRELIMINARY ANALYSIS OF THE ENERGY TRANSFER BETWEEN THE DARK SECTORS OF THE UNIVERSE

We study the mutual interaction between the dark sectors (dark matter and dark energy) of the Universe by resorting to the extended thermodynamics of irreversible processes and constrain the former with supernova type Ia data. As a by-product, the present dark matter temperature results are not extremely small and can meet the independent estimate of the temperature of the gas of sterile neutrinos.

Comparison of biological behavior between early-stage adenocarcinoma and squamous cell carcinoma of the uterine cervix

Objectives: (1) To compare the anatomopathological variables and recurrence rates in patients with early-stage adenocarcinoma (AC) and squamous cell carcinoma (SCC) of the uterine cervix; (2) to identify the independent risk factors for recurrence. Study design: This historical cohort study assessed 238 patients with carcinoma of the uterine cervix (113 and IIA), who underwent radical hysterectomy with pelvic lymph node dissection between 1980 and 1999. Comparison of category variables between the two histological types was carried out using the Pearson`s X-2 test or Fisher exact test. Disease-free survival rates for AC and SCC were calculated using the Kaplan-Meier method and the curves were compared using the log-rank test. The Cox proportional hazards model was used to identify the independent risk factors for recurrence. Results: There were 35 cases of AC (14.7%) and 203 of SCC (85.3%). AC presented lower histological grade than did SCC (grade 1: 68.6% versus 9.4%; p < 0.001), lower rate of lymphovascular space involvement (25.7% versus 53.7%; p = 0.002), lower rate of invasion into the middle or deep thirds of the uterine cervix (40.0% versus 80.8%; p < 0.001) and lower rate of lymph node metastasis (2.9% versus 16.3%; p = 0.036). Although the recurrence rate was lower for AC than for SCC (11.4% versus 15.8%), this difference was not statistically significant (p = 0.509). Multivariate analysis identified three independent risk factors for recurrence: presence of metastases in the pelvic lymph nodes, invasion of the deep third of the uterine cervix and absence of or slight inflammatory reaction in the cervix. When these variables were adjusted for the histological type and radiotherapy status, they remained in the model as independent risk factors. Conclusion: The AC group showed less aggressive histological behavior than did the SCC group, but no difference in the disease-free survival rates was noted. (C) 2006 Elsevier Ireland Ltd. All rights reserved.

Effects of long-term diabetes on the structure and cell proliferation of the myometrium in the early pregnancy of mice

P>It is known that the development of diabetic complications in human pregnancy is directly related to the severity and the duration of this pathology. In this study, we developed a model of long-term type 1 diabetes to investigate its effects on the cytoarchitecture, extracellular matrix and cell proliferation during the first adaptation phase of the myometrium for pregnancy. A single dose of alloxan was used to induce diabetes in mice prior to pregnancy. To identify the temporal effects of diabetes the mice were divided into two groups: Group D1 (females that became pregnant 90-100 days after alloxan); Group D2 (females that became pregnant 100-110 days after alloxan). Uterine samples were collected after 168 h of pregnancy and processed for light and electron microscopy. In both groups the histomorphometric evaluation showed that diabetes promoted narrowing of the myometrial muscle layers which was correlated with decreased cell proliferation demonstrated by PCNA immunodetection. In D1, diabetes increased the distance between muscle layers and promoted oedema. Contrarily, in D2 the distance between muscle layers decreased and, instead of oedema, there was a markedly deposition of collagen in the myometrium. Ultrastructural analysis showed that diabetes affects the organization of the smooth muscle cells and their myofilaments. Consistently, the immunoreaction for smooth muscle alpha-actin revealed clear disorganization of the contractile apparatus in both diabetic groups. In conclusion, the present model demonstrated that long-term diabetes promotes significant alterations in the myometrium in a time-sensitive manner. Together, these alterations indicate that diabetes impairs the first phenotypic adaptation phase of the pregnant myometrium.

Deiodinase-mediated thyroid hormone inactivation minimizes thyroid hormone signaling in the early development of fetal skeleton

Thyroid hormone (TH) plays a key role on post-natal bone development and metabolism, while its relevance during fetal bone development is uncertain. To Study this, pregnant once were made hypothyroid and fetuses harvested at embryonic days (E) 12.5, 14.5, 16.5 and 18.5. Despite a marked reduction in fetal tissue concentration of both T4 and T3, bone development, as assessed at the distal epiphyseal growth plate of the femur and vertebra, was largely preserved Lip to E16.5. Only at E18.5, the hypothyroid fetuses exhibited a reduction in femoral type I and type X collagen and osteocalcin mRNA levels, in the length and area of the proliferative and hypertrophic zones, in the number of chondrocytes per proliferative column, and in the number of hypertrophic chondrocyres, in addition to a slight delay in endochondral and intramembranous ossification. This Suggests that LIP to E 16.5, thyroid hormone signaling in bone is kept to a minimum. In fact, measuring the expression level of the activating and inactivating iodothyronine deiodinases (D2 and D3) helped understand how this is achieved. D3 mRNA was readily detected as early as E14.5 and its expression decreased markedly (similar to 10-fold) at E18.5, and even more at 14 days after birth (P14). In contrast. D2 mRNA expression increased significantly by E18.5 and markedly (similar to 2.5-fold) by P14. The reciprocal expression levels of D2 and D3 genes during early bone development along with the absence of a hypothyroidism-induced bone phenotype at this time Suggest that coordinated reciprocal deiodinase expression keeps thyroid hormone signaling in bone to very low levels at this early stage of bone development. (c) 2008 Elsevier Inc. All rights reserved.

Signature of the interaction between dark energy and dark matter in galaxy clusters

We investigate the influence of ail interaction between dark energy and dark matter upon the dynamics of galaxy clusters. We obtain file general Layser-Irvine equation in the presence of interactions, and find how, in that case. the virial theorem stands corrected. Using optical, X-ray and weak lensing data from 33 relaxed galaxy clusters, we put constraints on the strength of the coupling between the dark sectors. Available data Suggests that this coupling is small but positive, indicating that dark energy might be decaying into dark matter. Systematic effects between the several mass estimates, however, should be better known, before definitive conclusions oil the magnitude and significance of this coupling could be established. (C) 2009 Published by Elsevier B.V.

Thermodynamical description of the interaction between holographic dark energy and dark matter

We present a thermodynamical description of the interaction between holographic dark energy and dark matter. If holographic dark energy and dark matter evolve separately, each of them remains in thermodynamic equilibrium. A small interaction between them may be viewed as a stable thermal fluctuation that brings a logarithmic correction to the equilibrium entropy. From this correction we obtain a physical expression for the interaction which is consistent with phenomenological descriptions and passes reasonably well the observational tests: (c) 2008 Elsevier B.V. All rights reserved.

Longitudinal scaling property of the charge balance function in Au plus Au collisions at root s(NN)=200 GeV

We present measurements of the charge balance function, from the charged particles, for diverse pseudorapidity and transverse momentum ranges in Au + Au collisions at root S(NN) = 200 GeV using the STAR detector at RHIC. We observe that the balance function is boost-invariant within the pseudorapidity coverage vertical bar-1.3, 1.3 vertical bar. The balance function properly scaled by the width of the observed pseudorapidity window does not depend on the position or size of the pseudorapidity window. This scaling property also holds for particles in different transverse momentum ranges. In addition, we find that the width of the balance function decreases monotonically with increasing transverse momentum for all centrality classes. (c) 2010 Elsevier B.V. All rights reserved.

Update on the correlation of the highest energy cosmic rays with nearby extragalactic matter

Data collected by the Pierre Auger Observatory through 31 August 2007 showed evidence for anisotropy in the arrival directions of cosmic rays above the Greisen-Zatsepin-Kuz`min energy threshold, 6 x 10(19) eV. The anisotropy was measured by the fraction of arrival directions that are less than 3.1 degrees from the position of an active galactic nucleus within 75 Mpc (using the Veron-Cetty and Veron 12th catalog). An updated measurement of this fraction is reported here using the arrival directions of cosmic rays recorded above the same energy threshold through 31 December 2009. The number of arrival directions has increased from 27 to 69, allowing a more precise measurement. The correlating fraction is (38(-6)(+7))%, compared with 21% expected for isotropic cosmic rays. This is down from the early estimate of (69-(+11)(13))%. The enlarged set of arrival directions is examined also in relation to other populations of nearby extragalactic objects: galaxies in the 2 Microns All Sky Survey and active galactic nuclei detected in hard X-rays by the Swift Burst Alert Telescope. A celestial region around the position of the radiogalaxy Cen A has the largest excess of arrival directions relative to isotropic expectations. The 2-point autocorrelation function is shown for the enlarged set of arrival directions and compared to the isotropic expectation. (C) 2010 Elsevier B.V. All rights reserved.

Chondrichthyans from the base of the Irati Formation (Early Permian, Parana Basin), Sao Paulo, Brazil

Three species of chondrichthyans are reported from conglomeratic sandstone at the base of the Lower Permian (Artinskian) Irati Formation (Parana Basin) near Rio Claro, Sao Paulo State, Brazil. The fossils include: 1) dispersed teeth of the petalodont ltapyrodus punctatus Silva Santos 1990, first described from the Permian (Artinskian) Pedra do Fogo Formation, Parnaiba Basin, Northeast Brazil; 2) a new species of tooth of the Order Orodontiformes; and 3) a new species of finspine of the Order Ctenacanthiformes. These fossils occur in an allochthonous assemblage of vertebrate remains including other Chondrichthyes, Xenacanthiformes and cladodonts, paleonisciform bony fish, and tetrapods. This discovery is a significant contribution to the sparse record of South American Chondrichthyes from the Early Permian and raises questions regarding the paleoenvironmental adaptations among these fish within Paleozoic basins of Brazil at this time. (C) 2010 International Association for Gondwana Research. Published by Elsevier B.V. All rights reserved.

A putative gnetalean gymnosperm Cariria orbiculiconiformis gen. nov et spec. nov from the Early Cretaceous of northern Gondwana

Cariria orbiculiconiformis gen. nov. et spec. nov., a gymnosperm with gnetoid characters is described from the upper Aptian Crato Formation of the Araripe Basin in northeastern Brazil. Gross-morphology and anatomical details have been studied and characters have been discussed in respect to various seed plants. Several of these characters fit best with those of Gnetales and their putative fossil allies. However, the fossil plant cannot be assigned to any known extinct or extant group of seed plants in their current circumscription. Stem gross-morphology, xylotomical characters and epidermal features indicate a gnetophytic relationship, whereas characters of the reproductive organs are rather distinct from those found in extant taxa. The reproductive unit of the new taxon represents a triple organ consisting of two dichasial ovulate structures and one median pollen-producing structure containing smooth, monosulcate, boat-shaped pollen in-situ. Each ovulate structure consists of two distinct pairs of bracts, a sterile one at the base and a fertile one forming a terminal orbicular capsule. Stiff processes found in the apex of the ovulate structure may represent micropylar tubes of seeds, as seen in the Bennettitales-Erdtmanithecales-Gnetales group. C orbiculiconiformis gen. nov. et spec. nov. was ans herbaceous or semi-shrub-like plant that may have been adapted to the r-strategy in a stressful environment. (C) 2011 Elsevier B.V. All rights reserved.

Cearania heterophylla gen. nov et sp nov., a fossil gymnosperm with affinities to the Gnetales from the Early Cretaceous of northern Gondwana

Vegetative and fertile shoots of a shrub-like seed plant from the late Aptian Crato Formation of Brazil are described as Cearania heterophylla Kunzmann, Mohr and Bernardes-de-Oliveira, gen. nov. et sp. nov. Anatomical details of the axes, epidermal features and separate ovulate and pollen producing organs indicate the gymnospermous nature of this plant. The vascular tissue of the axes includes tracheids with bordered pits and fiber tracheids. Vegetative shoots comprising at least three branching orders bear opposite-decussately arranged ovate to lanceolate, dorsiventrally flattened, parallelodromous, rather thick leaves that vary tremendously in size. The amphistomatic leaves bear (brachy-)paracytic stomatal complexes arranged in simple longitudinal files. The ovulate structure is interpreted as a terminally attached single globular ovule/seed surrounded by at least five to six lanceolate bracts. A terminally attached pollen-cone like structure grows on a lateral leafy shoot. The unusual character combination may indicate that the fossils belong to a hitherto unknown group with affinities to ephedroid Gnetales. Sterile shoots formerly often described as Podozamites, Nageiopsis or Lilites that are at least partly congeneric with C. heterophylla Kunzmann, Mohr and Bernardes-de-Oliveira, gen. nov. et sp. nov. had a wide geographic distribution during the Early Cretaceous. (C) 2009 Elsevier B.V. All rights reserved.