Climatic and geomorphologic cycles in a semiarid distributive fluvial system, Upper Cretaceous, Bauru Group, SE Brazil

Studies of distributive fluvial systems and their preserved successions envisage the distribution and orientation of architectural elements to be primarily controlled by channels radiating outward from fan apices, in many cases along an elongate basin margin. Conceptual models for such systems account for the downstream dynamics of the fluvial network, but with limited consideration of temporal geomorphic variations, resulting vertical organisation of architectural elements, or of the interplay of factors controlling system dynamics. To understand the external and internal architecture of distributive fluvial systems, and the factors that influence their sequential facies organisation, a sedimentary succession of the proximal portion of an Upper Cretaceous, semiarid, distributive fluvial system, located at the north-eastern margin of the Bauru Basin (Southeast Brazil), has been analysed in detail. Three fining- and thinning-upward fluvial sequences are identified, forming an interval separated at the top and the bottom by two palaeosol profiles. Each sequence is formed of channel and floodplain deposits. Two types of channel deposits are identified. One is composed of stacked sets of small-scale dune deposits, suggesting perennial and steady fluvial regime, associated with more humid climate periods. The other is composed of large-scale sets indicative of flattened dunes associated with unsteady and fast-changing fluvial flow, formed in quasi-supercritical flow regime conditions, associated with drier climate periods. The vertical alternation of these two types of channel deposits records the accumulation of a fluvial succession that responded to high-frequency, climate-induced cyclic change in bounding conditions. Two palaeosol profiles, at the top and at the bottom of the succession, indicate temporary interruptions and cessation of the fluvial sedimentation, likely related to avulsion of the fluvial belt. Thus, the studied succession reveals high-frequency climate-induced allogenic sedimentary cycles that occur within a long-period autogenic geomorphologic-induced sedimentary cycle. This work suggests that the internal architecture of the channel deposits can be used as a climate proxy, and that climate and geomorphology act jointly as notable factors to control the vertical organisation of distributive fluvial systems

Nature of the band gap of In2O3 revealed by first-principles calculations and x-ray spectroscopy

Bulk and surface sensitive x-ray spectroscopic techniques are applied in tandem to show that the valence band edge for In2O3 is found significantly closer to the bottom of the conduction band than expected on the basis of the widely quoted bulk band gap of 3.75 eV. First-principles theory shows that the upper valence bands of In2O3 exhibit a small dispersion and the conduction band minimum is positioned at Gamma. However, direct optical transitions give a minimal dipole intensity until 0.8 eV below the valence band maximum. The results set an upper limit on the fundamental band gap of 2.9 eV

A review exploring the overarching burden of Zika virus with emphasis on epidemiological case studies from Brazil

This paper explores the main factors for mosquito-borne transmission of the Zika virus by focusing on environmental, anthropogenic, and social risks. A literature review was conducted bringing together related information from this genre of research from peer-reviewed publications. It was observed that environmental conditions, especially precipitation, humidity, and temperature, played a role in the transmission. Furthermore, anthropogenic factors including sanitation, urbanization, and environmental pollution promote the transmission by affecting the mosquito density. In addition, socioeconomic factors such as poverty as well as social inequality and low-quality housing have also an impact since these are social factors that limit access to certain facilities or infrastructure which, in turn, promote transmission when absent (e.g., piped water and screened windows). Finally, the paper presents short-, mid-, and long-term preventative solutions together with future perspectives. This is the first review exploring the effects of anthropogenic aspects on Zika transmission with a special emphasis in Brazil

Phenotypic Plasticity Determines Cancer Stem Cell Therapeutic Resistance in Oral Squamous Cell Carcinoma

This work was funded by the National Centre for the 3Rs (NC3Rs) Grant G0900799/1 and Fellowship NC/K500495/1 and the Norwegian Research Council (NFR- 178601)

Stem cell factor and its soluble receptor (c-kit) in serum of asthmatic patients- correlation with disease severity

<p>Abstract</p> <p>Background</p> <p>SCF (stem cell factor) is a pleiotropic cytokine exerting its role at different stages of bone marrow development and affecting eosinophil activation, mast cells and basophil chemotaxis and survival. The aim of the study was to assess concentration of SCF and its soluble receptor c-kit (sc-kit) in peripheral blood of patients with asthma referring it to asthma severity and phenotype.</p> <p>Methods</p> <p>The study involved 107 patients with bronchial asthma, well characterized with respect to severity and 21 healthy controls. Concentration of SCF and sc-kit in the patients serum were measured by ELISA method.</p> <p>Results</p> <p>Mean serum SCF level in the group of asthmatics (n = 88) was significantly higher as compared to healthy controls (1010 pg/ml ± 37 vs 799 ± 33; p < 0,001). The level of SCF was higher in patients with severe asthma as compared to patients with non-severe asthma (1054 +/- 41 pg/ml vs 819 +/- 50; p < 0,01) and correlated with dose of inhaled glucocorticosteroids taken by the patients to achieve asthma control (R = 0,28; p < 0,01). The mean sc-kit serum level did not differ between asthmatic patients and healthy controls, however the level of sc-kit in non-severe asthmatics was significantly higher as compared to patients with severe asthma and healthy controls. In asthmatic patients (n = 63) the level of sc-kit correlated positively with FEV1% predicted value (R = 0,45; p < 0,001) and MEF25% predicted value (R = 0,33; p < 0,01). The level of sc-kit inversely correlated with the dose of inhaled glucocorticosteroids taken by the patients (R = -0,26; p < 0,01).</p> <p>Conclusion</p> <p>Serum levels of SCF and its soluble receptor c-kit seem to be reflect asthma severity suggesting a role for these molecules in asthmatic inflammation.</p

Finite element-based micromechanical modeling of the influence of phase properties on the elastic response of cementitious mortars

This study reports the influence of inclusion stiffness and its distribution on the stress distributions in the microstructural phases of different cementitious mortars using microstructure-guided finite element simulations. Randomly generated periodic microstructures with single/multiple inclusion sizes and random spatial distribution, subjected to periodic boundary conditions and a strain-controlled virtual testing regime are chosen for final analysis. Numerical simulations reveal: (i) the differences in locations/magnitudes of stress concentrations as a function of inclusion stiffness and size distribution, and (ii) the sometimes detrimental influence of matrix and interface stiffening/strengthening on the overall composite response, leading to material design strategies when non-conventional inclusions are used in cementitious systems for special properties. The constitutive behavior in the linear elastic regime is extracted based on the predicted dominant principal stresses and strains in the representative area element. Thus, in addition to the microstructural phase stresses, this methodology also provides predictions of the composite elastic modulus, which are observed to be more reliable than those obtained from analytical prediction models

Factors Associated with Tuberculosis Treatment Default in an Endemic Area of the Brazilian Amazon: A Case Control-Study

SETTING: Treatment default is a serious problem in tuberculosis control because it implies persistence of infection source, increased mortality, increased relapse rates and facilitates the development of resistant strains. OBJECTIVE: This study analyzed tuberculosis treatment default determinants in the Amazonas State to contribute in planning appropriate control interventions. DESIGN: Observational study with a retrospective cohort using Brazilian Disease Notification System data from 2005 to 2010. A nested case control study design was used. Patients defaulting from treatment were considered as 'cases' and those completing treatment as 'controls'. In the analysis, 11,312 tuberculosis patients were included, 1,584 cases and 9,728 controls. RESULTS: Treatment default was observed to be associated to previous default (aOR 3.20; p<0.001), HIV positivity (aOR 1.62; p<0.001), alcoholism (aOR 1.51; p<0.001), low education level (aOR 1.35; p<0.001) and other co-morbidities (aOR 1.31; p = 0.05). Older patients (aOR 0.98; p = 0.001) and DOT (aOR 0,72; p<0.01) were considered as protective factor for default. CONCLUSIONS: Associated factors should be considered in addressing care and policy actions to tuberculosis control. Information on disease and treatment should be intensified and appropriate to the level of education of the population, in order to promote adherence to treatment and counter the spread of multidrug resistance to anti-TB drugs

Deciphering the phase transition-induced ultrahigh piezoresponse in (K,Na)NbO3_{3}-based piezoceramics

Here, we introduce phase change mechanisms in lead-free piezoceramics as a strategy to utilize attendant volume change for harvesting large electrostrain. In the newly developed (K,Na)NbO$_{3}$ solid-solution at the polymorphic phase boundary we combine atomic mapping of the local polar vector with in situ synchrotron X-ray diffraction and density functional theory to uncover the phase change and interpret its underlying nature. We demonstrate that an electric field-induced phase transition between orthorhombic and tetragonal phases triggers a dramatic volume change and contributes to a huge effective piezoelectric coefficient of 1250 pm V$^{-1}$ along specific crystallographic directions. The existence of the phase transition is validated by a significant volume change evidenced by the simultaneous recording of macroscopic longitudinal and transverse strain. The principle of using phase transition to promote electrostrain provides broader design flexibility in the development of high-performance piezoelectric materials and opens the door for the discovery of high-performance future functional oxides