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The present work proposes a methodology to analyze the identification of constitutive model parameters for concrete. This procedure is an important step to develop reliable constitutive models for materials with complex mechanical behavior, as concrete. A parametric sensitivity analysis has been developed using a damage model applied to concrete performing numerical analyses in uniaxial states and plain concrete plate. To solve the identification problem, an inverse optimization technique based on bio-inspired computational algorithm has been applied. To validate the inverse problem results, reinforced concrete beams found in the literature have been used. Thus, a comparison between experimental results and the ones obtained from the proposed technique has been made observing an adherence index about 95%. Finally, it is possible to note that the proposed methodology is robust and efficient concerning to the automatization of the parametric identification problem discussed on this paper when compared to traditional techniques used in Structural Engineering in the context of damage constitutive models. [ABSTRACT FROM AUTHOR]

Concrete is a material of utmost importance in construction, and therefore various numerical models have been developed to satisfactorily represent its observed behavior. Within this perspective, damage models stand out, especially isotropic damage ones that can satisfactorily represent the nonlinearity characteristics resulting from stiffness deterioration having the added advantages of a few parameters to be identified. However, these models are dependent on experimental observations to determine the constitutive variables which greatly influence the accuracy of the obtained response. Therefore, using more robust identification techniques can improve the process of determining these internal variables. In this sense, this paper intends to contribute to the literature by using swarm intelligence bioinspired optimization techniques combined with a concrete damage model to determine its constitutive variables. Observable sources are obtained from complete stress–strain curve proposals obtained from the literature, and the optimization firefly and bee colony algorithms are used. The efficiency of these optimization algorithms is verified, as well as that of the damage model in uniaxial tension and compression situations. Willmott's correlation indexes reveal values close to 0.97, which indicates an excellent correlation between the generated numerical data and reference responses. [ABSTRACT FROM AUTHOR]

We have investigated the magnetic properties of Ni nanoaggregates produced by ion implantation in ZnO single crystals. Several deviations from classical models usually adopted to describe the magnetic properties of nanoparticle systems were found. The strain between host and Ni nanoaggregates induces a magnetic anisotropy with a preferred direction. We show that these anisotropy effects can be misinterpreted as a ferromagnetic or antiferromagnetic coupling among the nanoaggregates similar to that of an oriented, interacting nanocrystal ensemble. [ABSTRACT FROM AUTHOR]

Introduction: Pain in HIV/AIDS patients may have diverse mechanisms. Nearly half of the pain is neuropathic, reflecting injury from viral infection, opportunistic agents, or neurotoxic effects of antiretroviral therapy. Patient treatment is complex, particularly in the setting of antiretroviral therapy. We report the case of an AIDS patient with thalamic pain, followed in a chronic pain unit for 12 years. Case report: A 55-year-old male with AIDS and cerebral toxoplasmosis, sent to the chronic pain unit with thalamic pain (2002). He complained of severe pain (VAS 8) in the right hemibody with numbness, electric discharge, and altered thermal sensibility. Initial prescription was: gabapentin 1,600 mg/day, amitriptyline 50 mg/d paracetamol 1 g tid y AINEs en SOS. to cerebral toxoplasmosis]/AIDS patientay, and tramadol 100 mg twice daily. One year later, pain worsening lead to dose increase. In March 2007 we added baclofen to the prescription. Months later, due to renal lesion, it was necessary to change the therapeutic scheme. In 2012 we add clonazepam and mirtazapine. Pain control allowed dose reductions. The patient died in 2014. Discussion: Chronic pain in HIV-infected patients can be severe and disabling. Treatment is difficult as multiple mechanisms are involved. Antiretroviral therapy poses the risk of pharmacological interactions and drug toxicity. We emphasize ritonavir inhibition of CYP3A4 and CYP2D6, increasing plasmatic concentrations and toxicity of drugs metabolized by the same way. [ABSTRACT FROM AUTHOR]

Surface elemental analysis presenting high silver (Ag) contents have been regarded as reliable for original bulk composition of silver coins which are accordingly referred as being produced from very pure Ag alloys. Also, the extent in which the surface elemental composition analytical results are influenced by surface Ag enrichment has been disregarded in coins alloys with Ag finenesses greater than the Ag content indexed to the maximum value of copper (Cu) solid solubility in Ag – 91.2 wt.%. PIXE and EDXRF results obtained on Portuguese 11 dinheiros silver coins issued in the 16th century with a legal Ag fineness of 916.6 thousandths, show 4 to 7% higher Ag surface contents. As identified by LA-ICP-MS and μ-PIXE through coins thicknesses, the overestimation of the superficial measured Ag is associated to a Cu depletion gradient representing as much as 50% less Cu on surface than on the bulk of the coins. The subsurface microstructural characterization by SEM-EDS reveals the presence of an important superficial layer depleted of Cu-phase, with a thickness < 70 μm, resulting primarily from intergranular corrosion during the coin manufacturing process. These layers can only be accessed by destructive or invasive analysis, as thicknesses beyond the information emission depth obtained with EDXRF could not be identified by Ag Kα/Lα ratios. As showed by the combination of different methods of analysis, EDXRF, PIXE, SEM-EDS and LA-ICP-MS, the results obtained by surface analytical techniques may differ from the original bulk compositions for these high Ag content coins and should be taken cautiousness together with historical context and information. [ABSTRACT FROM AUTHOR]

A modular diagnosis system (MDS), based on the framework of fuzzy logic, is proposed for upflow anaerobic sludge blanket (UASB) reactors treating sewage. In module 1, turbidity and rainfall information are used to estimate the influent organic content. In module 2, a dynamic fuzzy model is used to estimate the current biogas production from on-line measured variables, such as daily average temperature and the previous biogas flow rate, as well as the organic load. Finally, in module 3, all the information above and the residual value between the measured and estimated biogas production are used to provide diagnostic information about the operation status of the plant. The MDS was validated through its application to two pilot UASB reactors and the results showed that the tool can provide useful diagnoses to avoid plant failures. [ABSTRACT FROM AUTHOR]

In this article, we show that for a WENO scheme to improve the numerical resolution of smooth waves, increasing to some extent the contribution of the substencils where the solution is less smooth is much more important than improving the accuracy at critical points. WENO-Z, for instance, achieved less dissipative results than classical WENO through the use of a high-order global smoothness measurement, τ , which increased the weights of less-smooth substencils. This time, we present a way of further increasing the relevance of less-smooth substencils by adding a new term to the WENO-Z weights that uses information which is already available in its formula. The improved scheme attains much better resolution at the smooth parts of the solution, while keeping the same numerical stability of the original WENO-Z at shocks and discontinuities. [ABSTRACT FROM AUTHOR]

Swimming abilities of wild-caught sand-smelt Atherina presbyter larvae were assessed as critical swimming speed ( Ucrit) throughout ontogeny. The mean Ucrit increased with size, ranging from 3·6 to 18·7 cm s−1, over the size range of 6·6-21·0 mm LT. This indicates that at hatching A. presbyter larvae, far from being passive floaters, are already capable of active behaviours, which may influence their dispersal patterns. [ABSTRACT FROM AUTHOR]

Borges RP, Sousa-Neto MD, Versiani MA, Rached-Júnior FA, De-Deus G, Miranda CES, Pécora JD. Changes in the surface of four calcium silicate-containing endodontic materials and an epoxy resin-based sealer after a solubility test. International Endodontic Journal, 45, 419-428, 2012. Abstract Aim To compare the changes in the surface structure and elemental distribution, as well as the percentage of ion release, of four calcium silicate-containing endodontic materials with a well-established epoxy resin-based sealer, submitted to a solubility test. Methodology Solubility of AH Plus, iRoot SP, MTA Fillapex, Sealapex and MTA-Angelus (MTA-A) was tested according to ANSI/ADA Specification 57. The deionized water used in the solubility test was submitted to atomic absorption spectrophotometry to determine and quantify Ca2+, Na+, K+, Zn2+, Ni2+ and Pb2+ ions release. In addition, the outer and inner surfaces of nonsubmitted and submitted samples of each material to the solubility test were analysed by means of scanning electron microscopy and energy-dispersive spectroscopy (SEM/EDX). Statistical analysis was performed by using one-way anova and Tukey's post hoc tests (α = 0.05). Results Solubility results, in percentage, sorted in an increasing order were −1.24 ± 0.19 (MTA-A), 0.28 ± 0.08 (AH Plus), 5.65 ± 0.80 (Sealapex), 14.89 ± 0.73 (MTA Fillapex) and 20.64 ± 1.42 (iRoot SP). AH Plus and MTA-A were statistically similar ( P > 0.05), but different from the other materials ( P < 0.05). High levels of Ca2+ ion release were observed in all groups except AH Plus sealer. MTA-A also had the highest release of Na2+ and K+ ions. Zn+2 ion release was observed only with AH Plus and Sealapex sealers. After the solubility test, all surfaces had morphological changes. The loss of matrix was evident and the filler particles were more distinguishable. EDX analysis displayed high levels of calcium and carbon at the surface of Sealapex, MTA Fillapex and iRoot SP. Conclusions AH Plus and MTA-A were in accordance with ANSI/ADA's requirements regarding solubility whilst iRoot SP, MTA Fillapex and Sealapex did not fulfil ANSI/ADA's protocols. High levels of Ca2+ ion release were observed in all materials except AH Plus. SEM/EDX analysis revealed that all samples had morphological changes in both outer and inner surfaces after the solubility test. High levels of calcium and carbon were also observed at the surface of all materials except AH Plus and MTA-A. [ABSTRACT FROM AUTHOR]

ZnO single crystals were implanted with Mn, Co and Ni with fluences between 1 × 10 cm and 1 × 10 cm and energy of 200 keV. Results indicate that aggregation of transition metal ions in the as implanted state occurs only in the case of Ni. After an annealing stage to recover the ZnO structure aggregation occurs for the higher fluences of all implanted species. For lower concentrations paramagnetic behaviour with magnetic moments close to those of individual ions is observed. No polarised impurity band is formed as a result of the presence of transition metal ions and all samples show electrical conduction by carriers in extended states of ZnO. Significant values of magnetoresistance are measured at low temperatures, where electrical transport is described by hopping mechanisms between localized states. The sign of the magnetoresistance is dependent of the doping ion and is correlated with the observed aggregation. [ABSTRACT FROM AUTHOR]

While plants of a single species emit a diversity of volatile organic compounds (VOCs) to attract or repel interacting organisms, these specific messages may be lost in the midst of the hundreds of VOCs produced by sympatric plants of different species, many of which may have no signal content. Receivers must be able to reduce the babel or noise in these VOCs in order to correctly identify the message. For chemical ecologists faced with vast amounts of data on volatile signatures of plants in different ecological contexts, it is imperative to employ accurate methods of classifying messages, so that suitable bioassays may then be designed to understand message content. We demonstrate the utility of ‘Random Forests’ (RF), a machine-learning algorithm, for the task of classifying volatile signatures and choosing the minimum set of volatiles for accurate discrimination, using data from sympatric Ficus species as a case study. We demonstrate the advantages of RF over conventional classification methods such as principal component analysis (PCA), as well as data-mining algorithms such as support vector machines (SVM), diagonal linear discriminant analysis (DLDA) and k-nearest neighbour (KNN) analysis. We show why a tree-building method such as RF, which is increasingly being used by the bioinformatics, food technology and medical community, is particularly advantageous for the study of plant communication using volatiles, dealing, as it must, with abundant noise. [ABSTRACT FROM AUTHOR]

This study investigates the problem of controller design for systems with uncertain sampling rates. The system is controlled through a communication network. The sampling period, within a given interval, is assumed to be time-varying and a simplified framework for the network-induced delay is considered. The overall system is thus described by an uncertain discrete-time model with time-varying parameters inside a polytope whose vertices are obtained by means of the Cayley–Hamilton theorem. A digital robust controller that minimises an upper bound to the ℋ∞ performance of the closed-loop networked control system (NCS) is determined. The design conditions rely on a particular parameter-dependent Lyapunov function and are expressed as bilinear matrix inequalities (BMIs) in terms of extra matrix variables, which may be explored in the search for a better system behaviour. Numerical examples illustrate the results. [ABSTRACT FROM AUTHOR]

Larval development of Gobius xanthocephalus with descriptions of the ontogeny of the main structures, changes in pigmentation patterns and allometric relationships are presented for the first time. No previous descriptions of G. xanthocephalus larvae are available and therefore field collected larvae were compared with larvae obtained under controlled conditions. The DNA of adults, juveniles and larvae was compared in order to validate identifications. The overall developmental sequence obtained agrees with those described for other gobies. Pigmentation patterns were, however, distinct from those of other sympatric Gobiidae allowing a clear identification of G. xanthocephalus larvae. Otolith microstructure analysis revealed a linear age and body length relationship, with an estimated larval growth rate of 0·28 mm day−1. [ABSTRACT FROM AUTHOR]

1. In the nursery pollination system of figs ( Ficus, Moraceae), flower-bearing receptacles called syconia breed pollinating wasps and are units of both pollination and seed dispersal. Pollinators and mammalian seed dispersers are attracted to syconia by volatile organic compounds (VOCs). In monoecious figs, syconia produce both wasps and seeds, while in (gyno)dioecious figs, male (gall) fig trees produce wasps and female (seed) fig trees produce seeds. 2. VOCs were collected using dynamic headspace adsorption methods on freshly collected figs from different trees using Super Q® collection traps. VOC profiles were determined using gas chromatography–mass spectrometry (GC–MS). 3. The VOC profile of receptive and dispersal phase figs were clearly different only in the dioecious mammal-dispersed Ficus hispida but not in dioecious bird-dispersed F. exasperata and monoecious bird-dispersed F. tsjahela. 4. The VOC profile of dispersal phase female figs was clearly different from that of male figs only in F. hispida but not in F. exasperata, as predicted from the phenology of syconium production which only in F. hispida overlaps between male and female trees. Greater difference in VOC profile in F. hispida might ensure preferential removal of seed figs by dispersal agents when gall figs are simultaneously available. 5. The VOC profile of only mammal-dispersed female figs of F. hispida had high levels of fatty acid derivatives such as amyl-acetates and 2-heptanone, while monoterpenes, sesquiterpenes and shikimic acid derivatives were predominant in the other syconial types. A bird- and mammal-repellent compound methyl anthranilate occurred only in gall figs of both dioecious species, as expected, since gall figs containing wasp pollinators should not be consumed by dispersal agents. [ABSTRACT FROM AUTHOR]

Our present understanding of exocytosis of catecholamines has benefited tremendously from the arrival of single-cell electrochemical methods (amperometry and voltammetry), electrophysiological techniques (whole-cell and patch capacitance) and from the combination of both techniques (patch amperometry). In this brief review, we will outline the strengths and limitations of amperometric and electrophysiological methods and highlight the major contribution obtained with the use of these techniques in chromaffin cells. [ABSTRACT FROM AUTHOR]

The hypothetical oxidation mechanism of paracetamol (PAR) has been investigated using quantum chemical calculations at the density functional theory (DFT)/B3LYP theory level with the 6-31G* basis set. The calculations using Cpd I for the cytochrome P-450 model showed that, for PAR oxidation, an initial hydrogen atom abstraction from the phenolic hydroxyl group is thermodynamically more favored by 12.04 kcal mol-1 than from the acetylamine nitrogen atom. Spin density calculations were performed for the radical formed by the hydrogen abstraction from the phenolic hydroxyl group and showed that the unpaired electron remains predominantly localized on the O7 phenolic oxygen (39%), C3 and C5 carbon atoms at ortho positions (27% and 26%, respectively) and C1 at para position (33%). The results also show that the formations of dimer and trimer radicals are energetically more favored than the formation of NAPSQI, which is in agreement with observed experimental results. © 2006 Wiley Periodicals, Inc. Int J Quantum Chem, 2006 [ABSTRACT FROM AUTHOR]

The dominant periods in time series of sea surface temperature (SST) of the south-eastern North Atlantic are determined and related to atmospheric forcing and ocean dynamics. We analyse five-day composite images of a 10.5-year-long (from 10 July 1981 to 31 December 1991) time series of Advanced Very High Resolution Radiometer (AVHRR) onboard NOAA satellites. The dominant signal present in the whole region is the annual cycle. It explains 70% of the SST variance in the northern region and 40% in the southern. The pattern of the annual amplitudes is related to the seasonal cooling and warming cycle in the region. The second dominant period is a semi-annual frequency, estimated by means of periodograms of the residual time series with the annual cycle subtracted. This semi-annual frequency is responsible of making short springs and long autumns. The semi-annual frequency is present in 44% of the time series in the region, contrary to the generalized idea that a time series must always contain it. The geographical distribution of the semi-annual component of SST suggests that it is associated with the curl of the wind stress. The third dominant period is four years, found in three different areas: south of the Canary islands, off the Cape Verde islands and towards the northwest of Lanzarote Island. The main effect of this signal is to increase the maximum temperature every four years and to decrease the minimum temperature two years later. The 4-year signal does not seem to be associated with any atmospheric forcing field. The presence of a signal in the curl of the wind stress with periodicities of 25–30 days located south of the Canary Islands led us to conclude that the curl of the wind stress is important for the generation and shedding of eddies downstream these islands. [ABSTRACT FROM AUTHOR]

Assesses patterns of spatial variability of plant phosphorus and potassium (K) content of no-till corn and soybean on eight fields with varied histories of fertilization. What is required in the use of precision farming technologies; Information on composite whole-plant samples collected in the study.

Thin films of BaFeO3-δ have been deposited by pulsed injection metal-organic chemical vapor deposition. The films adopt a pseudocubic structure as a result of the match with the cubic structure of the SrTiO3 substrate and the accommodation of a high density of oxygen vacancies. They display antiferromagnetic behavior at room temperature and high electrical resistance. Furthermore, we observed an ageing effect that may be recovered to some extent by annealing in oxygen atmosphere. [ABSTRACT FROM AUTHOR]

The magnetic, transport, and structural properties of (La[sub 0.1]Sr[sub 0.3])MnO[sub 3] films deposited on MgO (001) are reported as a function of thickness and substrate temperature. The substrate temperature is fundamental in determining the structural properties and a deviation from the optimum temperature (680 °C) leads to grain boundaries and an imperfect (001) texture. Films with different thicknesses were deposited at the optimum deposition temperature. Magnetization and resistivity measurements on these films are interpreted in terms of magnetic and electric "dead" layers. The electric dead layer is an insulating layer approximately 4 nm thick while the magnetic dead layer is a region of weakly coupled noncollinear spins approximately 10 nm thick at each interface. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The advection–dispersion phenomenon can be observed in various fields of science. Mathematically, this process can be studied by considering empirical models, high-order differential equations, and fractional differential equations. In this paper, a fractional model considered to represent the transport of passive tracers carried out by fluid flow in a porous media is studied both in the direct and inverse contexts. The studied mathematical model considers a one-dimensional fractional advection–dispersion equation with fractional derivative boundary conditions. The solutions of both direct and inverse problems are obtained by using the orthogonal collocation method and the differential evolution optimization algorithm approaches, respectively. In this case, the source term along the spatial and time coordinates is taken as a design variable. The obtained results with the solution of the direct problem are compared with those determined by using an implicit finite difference scheme. The results indicate that the proposed approach characterizes a promising methodology to solve the direct and inverse fractional advection–dispersion problems. [ABSTRACT FROM AUTHOR]

In this work, we apply the spatial recurrence quantification analysis (RQA) to identify chaotic burst phase synchronisation in networks. We consider one neural network with small-world topology and another one composed of small-world subnetworks. The neuron dynamics is described by the Rulkov map, which is a two-dimensional map that has been used to model chaotic bursting neurons. We show that with the use of spatial RQA, it is possible to identify groups of synchronised neurons and determine their size. For the single network, we obtain an analytical expression for the spatial recurrence rate using a Gaussian approximation. In clustered networks, the spatial RQA allows the identification of phase synchronisation among neurons within and between the subnetworks. Our results imply that RQA can serve as a useful tool for studying phase synchronisation even in networks of networks. [ABSTRACT FROM AUTHOR]

The use of robust design techniques such as the one based onandfor tuning proportional integral (PI) and proportional integral derivative (PID) controllers have been limited to address a small set of processes. This work addresses the problem by considering a wide set of possible plants, both first- and second-order continuous-time systems with time delays and zeros, leading to PI and PID controllers. The use of structured uncertainties to handle neglected dynamics allows to expand the range of processes to be considered. The proposed approach takes into account the robustness of the controller with respect to these structured uncertainties by using the small-gain theorem. In addition, improved performance is sought through the minimisation of an upper bound to the closed-loop systemnorm. A Lyapunov–Krasovskii-type functional is used to obtain delay-dependent design conditions. The controller design is accomplished by means of a convex optimisation procedure formulated using linear matrix inequalities. In order to illustrate the flexibility of the approach, several examples considering recycle compensation, reduced-order controller design and a practical implementation are addressed. Numerical experiments are provided in each case to highlight the main characteristics of the proposed design method. [ABSTRACT FROM AUTHOR]

Objective: Laparoscopic ureteropyeloplasty is a widely accepted treatment option for the obstructed ureteropelvic junction (UPJ). Although it is often a straightforward surgical procedure, there may be technical difficulties in the case of concomitant stone burden, with multiple calicial, small, mobile stones. The authors describe a modification to the classic coagulum pyelolitothomy, using a mixture based on commercially available fibrin sealant, first used in the laparoscopic era. Methods: During a laparoscopic transperitoneal dismembered ureteropyeloplasty complemented with coagulum pyelolithotomy, the following steps are suggested: (1) Exposure of the UPJ; (2) ureter clamping with a vessel loop 2 cm distal to the UPJ (to allow pelvis filling); (3) transabdominal puncture of the pelvis with an 18-G, 20-cm needle (under laparoscopic vision) and urine aspiration; (4) recording the volume of urine aspirated; (5) preparing an equal volume of fibrin sealant (to avoid overdistention of the pelvis); (6) injecting the sealer protein solution through that needle + 1 mL of methylene blue (color the coagulum and facilitate its identification in the removal procedure); (7) insertion of another needle to inject the thrombin solution; (8) wait 5 minutes to allow coagulum cast formation; (9) circumferential excision of the UPJ; (10) coagulum removal; (11) pelvis plastic reduction (if needed) and ureter spatulation; (12) double-J stent placement; and (13) tension-free anastomosis completion. Results: The procedure results in the extraction of a tenacious coagulum containing more stones than normally anticipated from the x-ray studies. Conclusions: This technique modification reduces the incidence of incomplete stone removal, when there are small, free stones lying in a large renal pelvis. [ABSTRACT FROM AUTHOR]

Products of the umuD gene in Escherichia coil play key roles in coordinating the switch from accurate DNA repair to mutagenic translesion DNA synthesis (TLS) during the SOS response to DNA damage. Homodimeric UmuD2 is up-regulated 10-fold immediately after damage, after which slow autocleavage removes the N-terminal 24 amino acids of each UmuD. The remaining fragment, UmuD′2, is required for mutagenic TLS. The small proteins UmuD2 and UmuD′2 make a large number of specific protein-protein contacts, including three of the five known E. coil DNA polymerases, parts of the replication machinery, and RecA recombinase. We show that, despite forming stable homodimers, UmuD2 and UmuD′2 have circular dichroism (CD) spectra with almost no tv-helix or 13-sheet signal at physiological concentrations in vitro. High protein concentrations, osmolytic crowding agents, and specific interactions with a partner protein can produce CD spectra that resemble the expected 13-sheet signature. A lack of secondary structure in vitro is characteristic of intrinsically disordered proteins (IDPs), many of which act as regulators. A stable homodimer that lacks significant secondary structure is unusual but not unprecedented. Furthermore, previous single-cysteine cross-linking studies of UmuD2 and UmuD′2 show that they have a nonrandom structure at physiologically relevant concentrations in vitro. Our results offer insights into structural characteristics of relatively poorly understood IDPs and provide a model for how the umuD gene products can regulate diverse aspects of the bacterial SOS response. [ABSTRACT FROM AUTHOR]

The paper presents a technique for the segmentation of the fibro-glandular disc in mammograms based upon a statistical model of breast density. The density function of the model was represented by a mixture of up to four weighted Gaussians, each one corresponding to a specific density class in the breast. The parameters of the model and the number of tissue classes in the breast were determined using the expectation-maximisation algorithm and the minimum description length method. Grey-level statistics of the pectoral muscle were used to determine the tissue categories that are likely to represent the fibro-glandular disc. The method was applied to 84 medio-lateral oblique mammograms from the Mini-MIAS database. The results of the segmented fibro-glandular disc were assessed by a radiologist using the original and the segmented images, with reference to a ranking table categorising the results of segmentation as: 1: excellent; 2: good; 3: average; 4: poor; and 5: complete failure. Of the 84 cases analysed, 64.3% were rated as excellent, 16.7% were rated as good, 10.7% were rated as average, and 4.7% were rated as poor; only 3.6% of the cases were rated as a complete failure with regard to segmentation of the fibro-glandular disc. [ABSTRACT FROM AUTHOR]

Water stress is one of the most important abiotic factors affecting plants worldwide. This study compared the photochemical responses of two lineages of Crambe abyssinica (FMS CR 1307 and 1326) under water deficit (WD) conditions. The relative water content (RWC), stomatal conductance, chlorophyll (Chl) index, and Chl a fluorescence were evaluated. FMS CR 1326 showed greater reductions in RWC under WD. The FMS CR 1307 showed greater reductions in the connectivity of energy (L-band) and electron transfer from the oxygen-evolving complex (K-band), followed by a lower ability to maintain the reduction of plastoquinone. However, the increased size of the pool of the final electron acceptors in PSI for this lineage was observed. The FMS CR 1326 plant lineage showed an advantage over the FMS CR 1307 in terms of stability and efficiency of PSII under low water availability conditions. [ABSTRACT FROM AUTHOR]

Although barium ferrate is known to accommodate a range of oxygen stoichiometries, which give rise to distinct magnetic properties, the mechanism underlying this coupling is not clearly understood. In order to address this issue, the electronic and magnetic properties of pseudocubic BaFeO3-δ with 0 ≤δ≤ 0.5 were studied using density functional theory. The present results attest the influence of the oxygen content on the magnetic order: for high oxygen content, the magnetic interactions are predominantly ferromagnetic whereas for oxygen deficient stoichiometries the antiferromagnetic interactions prevail. The threshold separating the two regimes is determined by the competition between double-exchange and super-exchange interactions which sensitively depend on the occupation of the oxygen band. Due to the high electronic affinity of the Fe ions in this compound, which results in a negative ligand to metal charge transfer energy, the system behaves as self-doped and the oxygen content has little effect on the 3d Fe band occupation, affecting instead the occupation of the anionic band. [ABSTRACT FROM AUTHOR]

Optical properties of ferromagnetic half-metallic full-Heusler Co2FeGe alloy are investigated experimentally and theoretically. Co2FeGe thin films were obtained by DC magnetron sputtering and show the saturation magnetization at T = 10 K of m≈5.6μB/f.u., close to the value predicted by the Slater-Pauling rule. First-principles calculations of the electronic structure and the dielectric tensor are performed using the full-potential linearized-augmented-plane-wave method in the generalized gradient approximation (GGA) and GGA + U approximation. The measured interband optical conductivity spectrum for the alloy exhibits a strong absorption band in the 1-4 eV energy range with pronounced fine structure, which agrees well with the calculated half-metallic spectrum of the system, suggesting a near perfect spin-polarization in the material. [ABSTRACT FROM AUTHOR]

Brain plasticity refers to brain’s ability to change neuronal connections, as a result of environmental stimuli, new experiences, or damage. In this work, we study the effects of the synaptic delay on both the coupling strengths and synchronization in a neuronal network with synaptic plasticity. We build a network of Hodgkin-Huxley neurons, where the plasticity is given by the Hebbian rules. We verify that without time delay the synapses become regulated by both the nature (excitatory or inhibitory) and the frequency of the presynaptic and postsynaptic neuron. A presynaptic excitatory (inhibitory) neuron with higher (lower) frequency enhances the synaptic strength if the postsynaptic excitatory (inhibitory) neuron has lower (higher) frequency. When the delay is increased the network presents a non-trivial topology. Regarding the synchronization, only for small values of the synaptic delay this phenomenon is observed. [ABSTRACT FROM AUTHOR]

The double perovskite Ca[sub 2]FeMoO[sub 6] is a poor metal which orders magnetically at 345 K. The [sup 57]Fe Mo¨ssbauer hyperfine field and isomer shift at 4.2 K (48 T and 0.70 mm/s relative to α-Fe) indicate an Fe[sup 3+] configuration 3d[sup 5↑] which is strongly hybridized with the Mo 4d[sup ↓]t[sub 2g] orbitals. The saturation magnetization of 3.6μ[sub B]/formula is consistent with neutron diffraction measurements which indicate iron and molybdenum moments of 4.0(1) and -0.2(3)μ[sub B] per iron or molybdenum, respectively. The sample exhibits approximately 6% cation disorder relative to the ideal NaCl-type order of Fe and Mo in the double perovskite structure. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

A series of copper (Cu)-containing glasses were synthesized and incorporated into a SiO-ZnO-CaO-SrO-PO-based glass system. Additions of 6 and 12 mol% CuO retained the amorphous character, and glasses were processed to possess similar particle sizes and surface areas. Glass characterization using X-ray photoelectron spectroscopy and magic angle spinning nuclear magnetic resonance determined that the addition of 12 mol% CuO increased the fraction of Q-speciation and the concentration of bridging oxygens. Each glass presented solubility profiles for the release of Si (18-31 mg/L), Ca (13-16 mg/L), Zn (<3 mg/L) and Sr(2-10 mg/L); however, no Cu or P were released. Cu-GPCs were formulated, and the working time ( T ) and setting times ( T ) were found to be dependent on both polyacrylic acid concentration and CuO addition. The mechanical properties, i.e. the compressive strength (18-30 MPa) and the adhesive bond strength (0.79-1.32 MPa), were relative low which is likely due to the glass structure. Antibacterial properties were evaluated in E. coli (4 mm), S. epidermidis (10 mm), S. aureus (UMAS-1) and vancomycin resistant S. aureus (2 mm) and presented antibacterial effects in each microbe tested. [ABSTRACT FROM AUTHOR]

Larval development and allometric growth patterns of the black-faced blenny Tripterygion delaisi are described from a larval series (body length, LB = 3·30-12·10 mm) caught by light traps at the Arrábida Marine Park, Portugal. Larvae of T. delaisi possess distinctive morphometric and meristic characteristics which can be used to identify this species from related taxa. Pigmentation is sparse but characteristic, consisting of pigmented eyes, gas bladder pigmentation in the dorsal region, anal pigmentation and a row of regularly spaced postanal ventral melanophores. This pattern is present from as early as the yolk-sac stage and persists throughout all stages with just the addition of head and caudal pigmentation during the flexion and postflexion stages, respectively. The majority of fin development (with the exception of the caudal fin), occurs in the later stages of development. Myomere counts range between 37 and 45 for all stages. Growth is allometric during larval development. When inflexion points of growth were detected, growth was found to be biphasic with the inflexion points occurring within a very narrow range of LB (8·70-8·90 mm) close to the mean ± s.d. (9·44 ± 1·48 mm LB) of postflexion larvae. Considering allometric growth patterns and ontogenetic descriptions together, the first developmental phase includes the preflexion and flexion stage larvae, while the second phase characterises the postflexion larvae prior to the transition from larvae to juvenile. [ABSTRACT FROM AUTHOR]

Introduction: The Araguainha Dome, in south-central Brazil, is a 40 km impact structure, formed at ca. 254 Ma close to the time of the Permian-Triassic boundary. It offers a stratigraphic window into the sedimentary sequences and to the basement of the Paraná Basin. The basement crops out in the central part of the structure and is surrounded by a belt of polymict impact breccias (PIB), and strata from the lowermost part of the Paraná Basin: the Rio Ivaí Group (Ordovician-Silurian) and Furnas and Ponta Grossa formations (Devonian). The PIB at the Araguainha impact structure, well exposed in the northern and southern sectors of the central uplift, has been shown to be composed of a particulate matrix containing a heterogeneous population of lithic and mineral clasts, and cogenetic melt parti-cles; it, thus, represents suevite. Field study has indicated that the breccia contains large mega-clasts from the metasedimentary basement, mainly phyllite - some with evidence of contact metamorphism against the alkali granite, as well as metasandstone and metapelite. Quartz pebbles, conglomerates, and sandstones and pelites prob-ably derived from the lower part of the basin are also abundant as clasts. Until now, two types of impact melt rock, the so-called type-I and type-II, of different composition and emplacement styles, were identified. Type-I is the more abundant and the first one that was recognized; it is of granitic composition and always occurs in the granite core. The so-called type-II, subdivided into low silica content (LS <68%wt. SiO2) and high silica content (HS >80%wt. of SiO2), is always present as melted clasts in the suevite. In order to characterize the two types of IMR and to understand the relationship between them and the potential target rocks, geochemical and isotopic (Sr-Nd and U-Pb in zircon) data from the two types of impact melt rocks, target rocks, sedimentary units from the lower part of the Paraná basin and samples from the suevites (melted clasts plus matrix) were obtained. Results and conclusions: In the SiO2 vs. MgO diagram: the IMR type-I have a restricted geochemical composition, similar with the porphyritic granite, whereas the LS and HS IMR type-II have more heterogeneous geochemical composition but always similar with Cuiabá Group. The suevite matrix has a similar composition with the lower part of the Paraná basin, specifically the Furnas Formation. In the 87Sr/86Sr(251.5) vs. εNd(251.5) diagram, the granite has high 87Sr/86Sr and less negative εNd of ~9. The lower part of the Paraná basin has lowest 87Sr/86Sr ratios and more negative εNd of ~13. The samples from the Cuiabá Group and the two types of IMR show compositions between these two extremes. Eighty-eight concordant U-Pb isotope data were. The results, together with published data for the basement (Cuiabá Group) and the lower stratigraphic units of the Paraná Basin, were analyzed by multidimensional scaling (MDS) and with the kernel density estimation (KDE). Both suevite samples show a bimodal age population with the main peak at ~640 Ma and a second peak at 2000-2500 Ma. The MDS and KDE plots indicate that the provenance for the two suevite samples is similar to the zircon age populations for the formation in the lower part of the Paraná Basin sequence, very similar to the age population for the Furnas Formation. Based on these geochemical, isotopic and first U-Pb provenance results, we can conclude that: 1) the composition of the melted clast (IMR type-II) looks similar to the Cuiabá Group but the matrix shows a composition and provenance data similar with the lower part of the basin, it means that our field observations that initially favored a strong contribution of clastic material from the Cuiabá Group to the suevite need to be considered with caution and 2), possibly the two IMR do not have the same origin and they are not coming from the same type of target rocks, whereas the IMR type-I is clearly similar to the granite. 3) The IMR type-II is similar in composition to the Cuiaba Group samples or alternatively it represents a mixture between the Furnas and Rio Ivai formations. Finally, our geochemical, isotopic and provenance studies need to be extended statistically. These results will be very useful in determining how deep the transient cavity at Araguainha was excavated, and how deep the projectile may have penetrated into the target. Moreover, the results will contribute to modeling of the cratering processes related to the formation of the Araguainha impact structure. [ABSTRACT FROM AUTHOR]

We performed molecular dynamics computer simulations to elucidate the behavior and properties of the metal tetrasulfonated phthalocyanine molecule and the poly(amidoamine) dendrimers in self-assembly depositions, respectively, on poly(allylamine hydrochloride) polymer and on film formed by metal tetrasulfonated phthalocyanine with poly(allylamine hydrochloride). Important physical properties of phthalocyanines were obtained such as the kinetic energy and temperature in situ. By the semiempiricalmodel, we also obtained the UV-Vis absorption spectrum of the film for med by cobalt tetrasulfonated phthalocyanine deposited on poly(allylamine hydrochloride). We performed a study with poly(amidoamine) dendrimers on their deposition time on metal tetrasulfonated phthalocyanine, poly(allylamine hydrochloride) film, and we show the relationship of deposition time with the electrical charge and molecular mass of phthalocyanines. The deposition times of the dendrimers, as a function of their mass, were also elucidated. [ABSTRACT FROM AUTHOR]

Cryptic behavior and unpalatability are common defensive strategies that occur in different taxonomic groups, but the effectiveness of these defensive strategies is context dependent, varying with predator type and co-occurring species. We tested this assumption by measuring the mortality rates of Eupemphix nattereri (cryptic behavior) and Rhinella schneideri (unpalatable) tadpoles in association with the predatory fish Oreochromis niloticus (vertebrate) and the dragonfly larvae of Aeshna sp. (invertebrate). We designed a second experiment to evaluate whether fish predators are capable of learning to avoid unpalatable prey once they have encountered it. Our results showed that fish preyed selectively on palatable tadpoles, avoiding unpalatable tadpoles and that the odonate larvae were more efficient in preying on the more active unpalatable tadpoles and less efficient in capturing those tadpoles that presented cryptic behaviors. Additionally, our data suggest that the antipredator traits of tadpoles can interact with each other, with cryptic tadpoles showing lesser mortality when co-occurring with unpalatable tadpoles and odonate predators. Unpalatable tadpoles also increase the mortality of cryptic tadpoles in the presence of experienced fish predators. These prey traits interact in modifying the prey preference of the predator, which constitutes a prey-induced trait-mediated interaction (TMI). This type of TMI is dependent on the system complexity (number of predator and prey species interactions) and could define food web properties, such as the role of predators and the number of competitor species in the system. [ABSTRACT FROM AUTHOR]

Chronic kidney disease and sexual dysfunction are common entities in clinical practice in haemodialysis (HD) units. This article is a review of some articles that focus on sexual dysfunction in patients undergoing HD and its possible relationship in multiple ways. [ABSTRACT FROM AUTHOR]

Abstract: The morphology, composition, phase composition and corrosion products of coatings of pure Zn (obtained from two types of electrolytic bath: an acidic bath (Znacid) and a cyanide-free alkaline bath (Znalkaline)) and of Zn–Mn and Zn–Co alloys on steel substrates were studied. To achieve this, diverse techniques were used, including polarization curves, atomic force microscopy (AFM), scanning electron microscopy (SEM), glow discharge spectroscopy (GDS), X-ray diffraction (XRD), and the salt spray test. In the salt spray test, the exposure time required for the coatings to exhibit red corrosion (associated with the oxidation of steel) decreased in the following order: Zn–Mn(432h) >Zn–Co(429h) >Znalkaline(298h) >Znacid(216h). The shorter exposure times required for corrosion of the pure Zn coatings are related to the coating composition and the crystallographic structure. Analysis of the corrosion products disclosed that Zn5(OH)8Cl2·H2O was a corrosion product of all of the coatings tested. However, the formation of oxides of manganese (MnO, Mn0.98O2, Mn5O8) in the Zn–Mn coating, and the formation of the hydroxide Zn2Co3(OH)10·2H2O in the Zn–Co coating, produced more compact and stable passive layers, with lower dissolution rates. [Copyright &y& Elsevier]

The authors made an up-to-date review of the literature concerning the management of Zinner’s syndrome and evaluated a young patient with Zinner’s syndrome who had presented with urinary and ejaculatory complaints. Physical examination and transrectal ultra-sonography showed a 7.0 cm right seminal vesicle cyst. Magnetic resonance imaging (MRI) confirmed the diagnosis of Zinner’s syndrome. Oligoasthenoteratozoospermia was present at the two seminal analyses. Symptomatic improvement was achieved with conservative measures. Actually, the patient is still on a follow-up programme. The diagnosis is usually established at the age of increased sexual activity. Patients may be asymptomatic or present pain, irritative urinary or ejaculatory symptoms and infertility. MRI has proved to be the best imaging examination. Treatment should be adapted to symptoms, surveillance being the best option in the absence of clinical manifestations. Surgical approach may be adequate when conservative measures prove ineffective. Zinner’s syndrome should be suspected if a male young patient presents with unilateral renal agenesis and pelvic complaints and has a supraprostatic mass on digital rectal examination. The initial approach should be medical, but invasive procedures may be the only way to solve the patient’s complaints. Nowadays, laparoscopic and robotic techniques must replace the open surgical approach. [ABSTRACT FROM AUTHOR]

Abstract: The dynamic chemical plating (DCP) method is a wet deposition technique that has been shown to be a good alternative to produce deposits of single metals as Cu, Ni and Ag. In this work, the capability of DCP to deposit both binary (Ni–P) and ternary nickel alloys (Ni–P–B) is evaluated. These deposits are particularly interesting because of their mechanical and magnetic properties for technological applications. Results show that the composition of the deposited alloys is dependent on the chemical nature of the reducing agent and on the deposition conditions. It is shown that homogeneous deposits of binary Ni–P (5–7%, w/w P) and ternary Ni–B–P (4%, w/w of both B and P) alloys can be obtained by the DCP technique by the use of Na2HPO2 alone or Na2HPO2 +KBH4 mixtures as the reducing agents. Results show also that the composition of the films obtained determine properties that are critical to their envisaged applications, such as the capability for corrosion protection. [Copyright &y& Elsevier]

This article reviews the current status of research about the histogenesis and morphofunctional characteristics of chromaffin cells in the adrenal medulla. First, this study reports the selective migration, transcription and activation factors, and the morphological events of the chromaffin cell precursors during adrenal medulla development. Subsequently, the morphofunctional characteristics of adrenergic and non-adrenergic cells are considered, with particular reference to the characteristics of chromaffin granules and their biological steps, including their formation, traffic (storage, targeting and docking), exocytosis in the strict sense and recapture. Moreover, the relationship of chromaffin cells with other tissue components of the adrenal medulla is also revised, comprising the ganglion cells, sustentacular cells, nerves and connective-vascular tissue. [ABSTRACT FROM AUTHOR]

α1H T-type channels recruited by β1-adrenergic stimulation in rat chromaffin cells (RCCs) are coupled to fast exocytosis with the same Ca2+ dependence of high-threshold Ca2+ channels. Here we show that RCCs exposed to chronic hypoxia (CH) for 12–18 h in 3% O2 express comparable densities of functional T-type channels that depolarize the resting cells and contribute to low-voltage exocytosis. Following chronic hypoxia, most RCCs exhibited T-type Ca2+ channels already available at −50 mV with the same gating, pharmacological and molecular features as the α1H isoform. Chronic hypoxia had no effects on cell size and high-threshold Ca2+ current density and was mimicked by overnight incubation with the iron-chelating agent desferrioxamine (DFX), suggesting the involvement of hypoxia-inducible factors (HIFs). T-type channel recruitment occurred independently of PKA activation and the presence of extracellular Ca2+. Hypoxia-recruited T-type channels were partially open at rest (T-type ‘window-current’) and contributed to raising the resting potential to more positive values. Their block by 50 μm Ni2+ caused a 5–8 mV hyperpolarization. The secretory response associated with T-type channels could be detected following mild cell depolarizations, either by capacitance increases induced by step depolarizations or by amperometric current spikes induced by increased [KCl]. In the latter case, exocytotic bursts could be evoked even with 2–4 mm KCl and spike frequency was drastically reduced by 50 μm Ni2+. Chronic hypoxia did not alter the shape of spikes, suggesting that hypoxia-recruited T-type channels increase the number of secreted vesicles at low voltages, without altering the mechanism of catecholamine release and the quantal content of released molecules. [ABSTRACT FROM AUTHOR]

The animal-mediated pollination and seed-dispersal mutualisms of Ficus species give them key roles in tropical ecosystems, but may make them vulnerable to habitat fragmentation. The development of highly polymorphic markers is needed to analyse their genetic diversity and investigate the effects of fragmentation on gene flow. Of thirteen microsatellite loci isolated from Ficus insipida, a monoecious species in French Guiana, eleven were polymorphic (two to six alleles each). High levels of variation were found among loci; expected heterozygosities ranged from 0.151 to 0.715. All markers revealed a broad cross-species affinity when tested in 23 other Ficus species. [ABSTRACT FROM AUTHOR]

A method for the identification of the breast boundary in mammograms is presented. The method can be used in the preprocessing stage of a system for computer-aided diagnosis (CAD) of breast cancer and also in the reduction of image file size in picture archiving and communication system applications. The method started with modification of the contrast of the original image. A binarisation procedure was then applied to the image, and the chain-code algorithm was used to find an approximate breast contour. Finally, the identification of the true breast boundary was performed by using the approximate contour as the input to an active contour model algorithm specially tailored for this purpose. After demarcation of the breast boundary, all artifacts outside the breast region were eliminated. The method was applied to 84 medio-lateral oblique mammograms from the Mini-MIAS database. Evaluation of the detected breast boundary was performed based upon the percentage of false-positive and false-negative pixels determined by a quantitative comparison between the contours identified by a radiologist and those identified by the proposed method. The average false positive and false negative rates were 0.41% and 0.58%, respectively. The two radiologists who evaluated the results considered the segmentation results to be acceptable for CAD purposes. [ABSTRACT FROM AUTHOR]

The pectoral muscle represents a predominant density region in most medio-lateral oblique (MLO) views of mammograms; its inclusion can affect the results of intensity-based image processing methods or bias procedures in the detection of breast cancer. Local analysis of the pectoral muscle may be used to identify the presence of abnormal axillary lymph nodes, which may be the only manifestation of occult breast carcinoma. We propose a new method for the identification of the pectoral muscle in MLO mammograms based upon a multiresolution technique using Gabor wavelets. This new method overcomes the limitation of the straight-line representation considered in our initial investigation using the Hough transform. The method starts by convolving a group of Gabor filters, specially designed for enhancing the pectoral muscle edge, with the region of interest containing the pectoral muscle. After computing the magnitude and phase images using a vector-summation procedure, the magnitude value of each pixel is propagated in the direction of the phase. The resulting image is then used to detect the relevant edges. Finally, a post-processing stage is used to find the true pectoral muscle edge. The method was applied to 84 MLO mammograms from the Mini-MIAS (Mammographic Image Analysis Society, London, U.K.) database. Evaluation of the pectoral muscle edge detected in the mammograms was performed based upon the percentage of false-positive (FP) and false-negative (EN) pixels determined by comparison between the numbers of pixels enclosed in the regions delimited by the edges identified by a radiologist and by the proposed method. The average FP and FN rates were, respectively, 0.58% and 5.77%. Furthermore, the results of the Gabor-filter-based method indicated low Hausdorif distances with respect to the hand-drawn pectoral muscle edges, with the mean and standard deviation being 3.84 ± 1.73 mm over 84 images. [ABSTRACT FROM AUTHOR]

This paper presents the development of microwave Gallium nitride (GaN) heterostructure field-effect transistors (HFETs) on silicon (Si). GaN-on-Si provides a low-cost manufacturable platform that could lead to the commercialization of GaN-based power devices for wireless applications. Small periphery GaN high electron mobility transistors (HEMTs) on Si exhibited a maximum drain current of 900mA/mm, a peak g[sub m] of 300 mS/mm, and a microwave output power density of 1.5 W/mm at 2 GHz. Microwave characterization and device modeling of GaN HEMTs on Si are discussed. [ABSTRACT FROM AUTHOR]

For the variable effectiveness, this parameter was estimated at 100% for hysterectomies, and LNG-IUS effectiveness was calculated from 10% to 100% in order to identify the viability point. The relevant literature shows that LNG-IUS has > 70% effectiveness in bleeding volume reduction, thus the cost-effectiveness ratio was calculated for one and two devices in women aged 40-50 years. [Extracted from the article]