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The electro-thermal and optical properties of a bolometer based on an La0.7Sr0.3MnO3(LSMO) thin film with a detection area of 100 × 100 µm2 are presented. The LSMO thin film was epitaxially grown on CaTiO3/Si and patterned using a two-step etching process of ion-beam etching in argon and of reactive-ion etching in SF6, in order to etch LSMO/CaTiO3 and Si, respectively. The voltage-current (V–I) characteristics of the bolometer were measured in vacuum from 240 K to 415 K. From the V–I characteristics and a thermal model of the bolometer, the electrical responsivity was determined and compared to the optical responsivity measured with a laser diode at 635 nm. The noise equivalent power (NEP) as a function of frequency was measured by dividing the spectral noise power density by the optical responsivity. At 300 K and a bias current of 80 µA, the NEP was 2.3 × 10−11 W · Hz−1/2 in the 20–200 Hz modulation frequency range and the response time was 1.3 ms. The obtained NEP value without any absorbing layer or antennas, combined with the low value of the response time, are a very promising step towards the use of such LSMO-based bolometers for IR or THz detection. [ABSTRACT FROM AUTHOR]

Magnetic properties of sputtered NiFe/IrMn/Co trilayers grown on different seed layers (Cu or Ta) deposited on Si (100) substrates were investigated by magnetometry and ferromagnetic resonance measurements. Exchange bias effect and magnetic spring behavior have been studied by changing the IrMn thickness. As shown by X-ray diffraction, Ta and Cu seed layers provoke different degrees of (111) fcc-texture that directly affect the exchange bias and indirectly modify the exchange spring coupling behavior. Increasing the IrMn thickness, it was observed that the coupling angle between the Co and NiFe ferromagnetic layers increases for the Cu seed system, but it reduces for the Ta case. The results were explained considering (i) different anisotropies of the Co and IrMn layers induced by the different degree of the (111) texture and (ii) the distinct exchange bias set at the NiFe/IrMn and IrMn/Co interfaces in both systems. The NiFe and Co interlayer coupling angle is strongly correlated with both exchange bias and exchange magnetic spring phenomena. It was also shown that the highest exchange bias field occurs when an unstressed L12 IrMn structure is stabilized. [ABSTRACT FROM AUTHOR]

The ferromagnetic resonance (FMR) technique is used to study the exchange bias field in asymmetrical NiFe/FeMn/NiFe trilayers produced by dc magnetron sputtering under different working pressures. The FMR spectra give evidence of two resonance modes attributed to the two asymmetrical noninteracting NiFe layers. The study of the in-plane angular dependence of the absorption field allows the measurement of the exchange bias field at both bottom ferromagnetic (FM)/antiferromagnetic (AFM) and top AFM/FM interfaces. [ABSTRACT FROM AUTHOR]

We have the objective of discussing the paths taken by bachelors to teaching in Higher Education, in particular, about how the graduate influenced the trajectories that led them to teaching, considering that, in this course, images and experiences about being a teacher are built and Contribute to their actions as teachers. We question what has led a professional with training in baccalaureate to practice the teaching profession. We conducted a qualitative research based on the methodology of the Comprehensive Interview with thirteen teachers with a baccalaureate degree who work as teachers in Higher Education at the Federal University of Rio Grande do Norte. The Comprehensive Interview was the methodology chosen to consider it capable of understanding the multiplicity of meanings that led the bachelors to act as teachers, as well as help understand the relationship between their training as a Bachelor and the exercise of university teaching. Through the analysis of the interviewees' speeches, it can be seen that teachers report on the importance of Postgraduation for university teaching, considering it as the path that leads the bachelor to the teaching profession, although there is a need to broaden the discussion about The current formative profile of graduate programs in Brazil. [ABSTRACT FROM AUTHOR]

In this work, we consider a model derived from energy density for a Fermi gas in the Bardeen- Cooper-Schrieffer (BCS) superfluid state, trapped in a quasiperiodic one-dimensional optical lattice (OL). Reducing the equation to the 3D to 1D form, we construct families of stable 1D gap solitons (GSs) by the variational approximation (VA). In the linear limit, the VA predicts almost exact positions of narrow Bloch bands that separate the first gaps. Through the variational approximation, we show the possibility that the nonlinearity coefficient acting in a combination with the potential of the quasiperiodic one-dimensional optical lattice, allows one dimensional bright gap solitons to arise. Varying the amplitude of the optical lattice, we analyze the existence and stability of bright gap solitons using a gaussian ansatz. GSs are stable against small variations of the quasiperiodic optical lattice. This paper can be used as a learning guide in the study of cold atoms. Students are encouraged to perform variational calculations for other amplitude values of optical lattices. [ABSTRACT FROM AUTHOR]

The thermal decomposition of scandium nitrate is a complex process, which begins with the simultaneous condensation of 4 mol of the initial monomer Sc(NO)·6HO. The resulting cyclic tetramer ScO(NO)·2HO gradually loses azeotrope HO-HNO, and an intermediate oxynitrate ScO(NO) is formed. At higher temperature, this oxynitrate is destroyed leaving behind unstable dimer ScO which is transformed into scandium oxide. The molecular mechanics method used for comparison of the potential energies of consecutive products of thermal decomposition permits an evaluation of their stability and a proper interpretation of experimental data. The structural modeling was aimed to provide detailed information about the bond lengths and bond angles, filling the gap in what we know about amorphous oxynitrates. The models represent a reasonably good approximation to the real structures. [ABSTRACT FROM AUTHOR]

A set of hybrid ferromagnetic/superconductor heterostructures was prepared by a confocal DC magnetron sputtering setup. The samples were systematically studied by measuring the magnetization and magneto-transport properties up to 2.5 T. The anisotropic behavior of the critical temperature, under applied magnetic fields, was investigated. For the Nb/Cu/Co samples, the nucleation of the superconductivity is determined by the formation of a large distribution of out-of-plane magnetic domains in the ferromagnetic Co layer. In the regions between the Co magnetic domains, the results suggested that the effective magnetic field can be drastically reduced, favoring the nucleation of Cooper pairs responsible for the superconducting properties of the Nb films. Oppositely, in the Nb/Cu/Py samples, the superconducting properties were more severely depleted due to the increase of the effective magnetic field, caused by the combined effects of the applied and ferromagnetic Py stray field. Values of spin-valve effects at the interval 60–300 mK were obtained for the different hybrid Nb/Cu/Py (or Nb/Cu/Co) and Nb/Cu/Py/Cu/Co systems. The results were mainly explained considering the effective stray fields derived from the changes on the magnetic domains of the ferromagnetic layers caused by the external field. [ABSTRACT FROM AUTHOR]

We investigate the solutions of a one-dimensional mean-field hydrodynamic equation using a variational approximation (VA). We analytically model and compare two Bose-Einstein condensates which can be used to create bright gap solitons experimentally, one of them trapped by a double-periodic optical lattice and the other one trapped by a single-periodic optical lattice. No additional harmonic confinement was employed in both cases. Through the variational approximation, we study the possibility that the nonlinearity coefficient, in a combination with the potential of either the double-periodic or the single-periodic optical lattice, allows the appearance of one dimensional bright gap solitons. In both cases, we analyze the existence and stability of bright gap solitons using a Gaussian ansatz. This paper can be used as a learning guide in the study of cold atoms. Students are encouraged to perform variational calculations for other types of optical lattices. [ABSTRACT FROM AUTHOR]

The nonahydrate of iron(III) nitrate shows no phase transitions in the range of −40 to 0 °C. Both hexahydrate Fe(NO)·6HO and nonahydrate Fe(NO)·9HO have practically the same thermal behavior. Thermal decomposition of iron nitrate is a complex process which has a different mechanism than those described for other trivalent elements. Thermolysis begins with the successive condensation of 4 mol of the initial monomer accompanied by the loss of 4 mol of nitric acid. At higher temperature, hydrolytic processes continue with the gradual elimination of nitric acid from resulting tetramer and dimeric iron oxyhydroxide FeO(OH) is formed. After complete dehydration, oxyhydroxide is destroyed leaving behind 2 mol of FeO. The molecular mechanics method provides a helpful insight into the structural arrangement of intermediate compounds. [ABSTRACT FROM AUTHOR]

Thermal decomposition of chromium nitrate nonahydrate was studied by thermal analysis, differential scanning calorimetry, infrared spectroscopy, and high temperature X-ray diffraction, so that mass losses were related to the exactly coincident endothermic effects and vibrational energy levels of the evolved gases. The thermal decomposition of chromium nitrate is a complex process, which begins with the simultaneous dehydration and concurrent condensation of 4 mol of the initial monomer Cr(NO 3) 3·9H 2O. Soon after that, the resulting product Cr 4N 12O 36·31H 2O gradually loses water and azeotrope HNO 3 + H 2O, and is transformed into tetrameric oxynitrate Cr 4N 4O 16. At higher temperatures, the tetramer loses N 2O 3 and O 2 and a simultaneous oxidation of Cr(III) to Cr(IV) occurs. The resulting composition at this stage is chromium dioxide dimer Cr 4O 8. Finally, at 447  °C the unstable dimer loses oxygen and is transformed into 2Cr 2O 3. The models of intermediate amorphous compounds represent a reasonably good approximation to the real structures and a proper interpretation of experimental data. [ABSTRACT FROM AUTHOR]

Thermal decomposition of aluminum nitrate hydrate was studied by thermogravimetry, differential scanning calorimetry, and infrared spectroscopy, so that all mass losses were related to the exactly coincident endothermic effects and vibrational energy levels of the evolved gases. The process starts with the simultaneous condensation of two moles of the initial monomer Al(NO)·8HO. Soon after that, the resulting product Al(NO)·13HO gradually loses azeotrope HNO + HO, then NO and O and, through the formation of AlO(NO), is transformed into aluminum oxide. The molecular mechanics method used for comparison of the potential energies of consecutive products of thermal decomposition permits an evaluation of their structural arrangement. On the basis of the results obtained, a probable mechanism for the overall decomposition of Al(NO)·8HO has been proposed. [ABSTRACT FROM AUTHOR]

The thermal decomposition of yttrium nitrate hexahydrate Y(NO)·6HO is a complex condensation process generating a tetramer arrangement YO(NO) formed by alternating yttrium and oxygen atoms. The anions NO attach themselves to the yttrium atoms. The tetramer gradually loses NO and, through the formation of YO(NO), is transformed into yttrium oxide. The bond lengths and bond angles of intermediate oxynitrates calculated using the molecular mechanics method rendered data compatible with the results of X-ray diffraction for related compounds. [ABSTRACT FROM AUTHOR]

It is well established that gallium insertion into the hydroxiapatite matrix as practiced in orthopedics protects bone from resorbtion and improves the biomechanical properties of the skeletal system. The research presented in this article is an investigation into the thermal decomposition of gallium nitrate, which is part of a complex process leading to the preparation of a hybrid matrix. It was demonstrated that after melting of the hexahydrate in its own water there occurs a simultaneous condensation of 4 mol of initial monomer Ga(NO)·6HO into a tetramer GaO(NO). The resulting inorganic cycle gradually loses NO and, through the formation of unstable oxynitrates, is transformed into gallium oxide. The use of molecular mechanics for comparing the potential energies of consecutive products of thermal decomposition permitted an evaluation of their stability and an appropriate interpretation of the experimental data. [ABSTRACT FROM AUTHOR]

A novel wide-angle finite-difference beam-propagation method is applied to the analysis of confinement losses in photonic crystal fibers (PCFs). The method is formulated in terms of the locally one-dimensional (LOD) technique and Padé polynomials. It was found that the wide-angle approach allows an acceleration of the convergence rate of up to 50% for the effective-index imaginary part when compared to paraxial formalism. In this framework, an important aspect of PCF structures, namely, the random structural variation of the hole radius and pitch, which occurs during the fabrication process of these devices, is investigated in this paper. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 45: 568–573, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20882 [ABSTRACT FROM AUTHOR]

1. Salmonella Gallinarum strains isolated from a southern Brazil fowl typhoid outbreak were subjected to phenotypic and genotypic analyses to identify genetic elements that could improve prevention and control strategies.2. Whole-genome sequencing revealed the presence of the aac(6’)-Iaa gene, conferring aminoglycoside resistance, along with novel chromosomal point mutations, including the first detection of parE p.S451F in Salmonella Gallinarum.3. Additionally, IncFII(S) plasmid replicons, Salmonella pathogenicity islands and 105 virulence genes associated with cell adhesion, invasion and antimicrobial peptide resistance were identified.4. These findings shed light on the molecular mechanisms of fowl typhoid and provide crucial insights into emerging antimicrobial resistance and virulence factors. [ABSTRACT FROM AUTHOR]

1. Epidemiological surveillance of Salmonella spp. serves as a primary tool for maintaining the health of poultry flocks. Characterising circulating serotypes is crucial for implementing control and prevention measures. This study conducted phenotypic and molecular characterisation of S. enterica Pullorum, S. enterica Heidelberg, and S. enterica Corvalis isolated from broiler chickens during slaughtering. 2. All strains were susceptible to gentamicin, neomycin and norfloxacin. However, resistance rates exceeded 50% for ciprofloxacin and tiamulin, irrespective of the serotype. Approximately 64% of strains were classified as multidrug-resistant, with S. enterica Heidelberg strains exhibiting significantly higher overall resistance. The isolates demonstrated the ability to adhere and produce biofilm at a minimum of three temperatures, with S. enterica Pullorum capable of biofilm production at all temperatures encountered during poultry rearing. 3. Each strain possessed between two and seven different virulence-associated genes. Genetic similarity, as indicated by pulsed field gel electrophoresis, exceeded 90% for all three serotypes and strains were classified in the R5 ribotype by PCR, regardless of serotype. Sequencing revealed high similarity among all strains, with homology ranging from 99.61 to 100% and all were classified to a single cluster. 4. The results suggested a clonal relationship among the strains, indicating the possible circulation of a unique clonal group of S. enterica Pullorum in the southern region of Brazil. [ABSTRACT FROM AUTHOR]

Surface structure determination by Low Energy Electron Diffraction (LEED) is based on a comparison between experimentally measured and theoretically calculated intensity versus energy I(V) curves for the diffracted beams. The level of agreement between these, for different structural models, is quantified using a correlation function, the so-called R factor. Minimizing this factor allows one to choose the best structure for which the theoretical simulations are computed. Surface structure determination thus requires an exhaustive search of structural parameter space in order to minimize the R factor. This minimization is usually performed by the use of directed search methods, although they have serious limitations, most notably their inability to distinguish between false and real structures corresponding to local and global R factor minima. In this work we present the implementation of a global search method based on the simulated annealing algorithm, as suggested earlier by Rous, using the Van Hove and Tong standard LEED code and the results of its application to the determination of the structure of the Ag(111) and CdTe(110) surfaces. Two different R factors, R[sub P] and R[sub 1], have been employed in the structural searches, and the statistical topographies of these two factors were studied. We have also implemented a variation of the simulated annealing algorithm (Fast Simulated Annealing) and applied it to these same two systems. Some preliminary results obtained with this algorithm were used to compare its performance with the original algorithm proposed by Rous. [ABSTRACT FROM AUTHOR]

Spatial diversity assists parameter estimation in distributed networks. A sparsity-aware link combination strategy is proposed, which considers both the spatial sparsity in a network and the inherent sparsity of the system, where two types of zero-attracting adaptive combiners are proposed based on the least-mean-square the algorithm. The proposed algorithms exploit l1-norm regularisation through adaptive combination of neighbouring node weights such that the proposed algorithms can adaptively track the variations of the network topology. Simulation results illustrate the advantages of the proposed link combination algorithm in terms of convergence rate and steady-state performance for distributed sparse system learning. [ABSTRACT FROM AUTHOR]

Greedy algorithms are computationally efficient optimisation techniques for solving sparse recovery problems. Matching pursuit (MP) and orthogonal MP (OMP) are popular greedy algorithms; MP possesses the lowest complexity whereas OMP provides better performance. In this reported work, OMP is modified using dichotomous coordinate descent (DCD) iterations and an algorithm is arrived at that has performance close to that of OMP and complexity even lower than that of MP. [ABSTRACT FROM AUTHOR]

Ferroelectricity is expected to be observed in alkaline earth metal oxides (BaO, MgO, CaO, and SrO) with the application of adequate strain, according to theoretical predictions by Bousquet et al. The resultant polarization, dielectric constant, and piezoelectric response would be comparable to those of typical ferroelectric materials, like perovskites. In yet another recent work, Nascimento et al. explored these theoretical predictions by simulating the behaviour of ultra-thin films of BaO under applied in-plane strain to mimic the effect of epitaxial strain induced by an adequate substrate. Effects of both in-plane compressive strain as well as temperature, varied in the ranges of 0 to − 10% and 100–1500 K, respectively, were explored in the simulations. An antipolar phase was observed for in-plane compressive strain values from 3 to 10% and a temperature range of 100 to 1500 K. However, only a compressive strain value around 9%, typically too high to be obtained by epitaxial strain, was able to produce an ordered single domain. Polarization and ferroelectricity are well known as hard to obtain in ultra-thin films due to their limited thickness. The observed existence of an antipolar phase in ultra-thin films would in principle avoid the problems associated with uncompensated surface charges created by the discontinuity of the normal polarization component at the surface. However, can ferroelectricity be obtained in thicker films or even in bulk-like BaO systems? To answer this question, we will here explore the effects of in-plane compressive strain in BaO bulk systems. Compressive in-plane strain, along both x and y directions, will be varied in 0–10% range as well as the c/a (out-of-plane/in-plane) lattice ratio for values of 1.0–1.3. The observed structural phases and associated physical properties will be presented and discussed. [ABSTRACT FROM AUTHOR]

The hexahydrate Nd(NO3)3·6H2O melts in its water of crystallization at 328 K. There are no phase transitions at least above 233 K. Similar to other nitrates in the lanthanide series, its thermal decomposition is a gradual process, which entails the formation of a cluster 6[Nd(NO3)3·6H2O] after the condensation of 6 mol of the initial monomer. During this process, a multicomponent multiphase system exists far from equilibrium and is continuously maintained in this state until normal neodymium oxide is formed. The main volatile products of thermolysis are water, nitric acid, azeotrope 68% HNO3–32% H2O, nitrogen dioxide and oxygen. The proposed mechanism satisfactorily explains the mass losses in accordance with the experimental results. [ABSTRACT FROM AUTHOR]

Zakharov and V. Nascimento Greedy algorithms are computationally efficient optimisation techniques for solving sparse recovery problems. Matching pursuit (MP) and orthogonal MP (OMP) are popular greedy algorithms; MP possesses the lowest complexity whereas OMP provides better performance. In this reported work, OMP is modified using dichotomous coordinate descent (DCD) iterations and an algorithm is arrived at that has performance close to that of OMP and complexity even lower than that of MP. [ABSTRACT FROM AUTHOR]

The hexahydrate of praseodymium nitrate hexahydrate Pr(NO3)3·6H2O does not show phase transitions in the range of 233-328 K when the compound melts in its own water of crystallization. It is suggested that the thermal decomposition is a complex step-wise process, which involves the condensation of 6 mol of the initial monomer Pr(NO3)3·6H2O into a cyclic cluster 6[Pr(NO3)3·6H2O]. This hexamer gradually loses water and nitric acid, and a series of intermediate amorphous oxynitrates is formed. The removal of 68% HNO3-32% H2O azeotrope is essentially a continuous process occurring in the liquid phase. At higher temperatures, oxynitrates undergo thermal degradation and lose water, nitrogen dioxide and oxygen, leaving behind normal praseodymium oxide Pr2O3. The latter absorbs approximately 1 mol of atomic oxygen from N2O5 disproportionation, giving rise to the non-stoichiometric higher oxide Pr2O3.33. All mass losses are satisfactorily accounted for under the proposed scheme of thermal decomposition. [ABSTRACT FROM AUTHOR]

The thermal decomposition of lutetium nitrate starts with essentially a process of dehydration of the initial monomer Lu(NO3)3·3H2O with further condensation into a hexamer Lu6N18O54·6H2O. The latter decomposes in four steps with release of water, azeotrope 68% HNO3–32% H2O, nitric acid, nitrogen dioxide and oxygen. The resulting intermediate compounds are lutetium oxynitrates Lu6N4O19 and Lu6N2O14. After complete denitrification at high temperatures, they are converted into unstable trimer Lu6O18 which is destroyed leaving behind lutetium oxide. All mass losses are accounted for, step by step. The intermediates were characterized using thermal analysis, infrared spectroscopy and X-ray diffractometry. The models of intermediate oxynitrates obtained with the molecular mechanics technique represent a reasonably good approximation to the real structures. [ABSTRACT FROM AUTHOR]

An experimental method was developed to set the magnetization direction in ferromagnetic layers of Si(100)/Cu/NiFe/Cu/Co/IrMn/Cu morphologically modified spin valves. Large uniaxial anisotropies emerged in the NiFe and Co layers due to modifications of their morphologies induced by the shadowing effect that arises from oblique depositions. Therefore, we set the uniaxial anisotropy axes in pre-set directions by controlling the sputtered beam direction relative to the sample reference. We were able to tune the angle between the magnetization directions of the NiFe and Co layers in a continuous interval from 0° to 90° due to the interplay between the Co and NiFe uniaxial anisotropies and the unidirectional anisotropy at the Co/IrMn interface. This type of noncollinear coupling cannot be found in conventional spin valve devices with passive spacers through which the coupling is governed by bilinear and biquadratic couplings. The methodology of preparation proposed here allows an extra control over the magnetism of the spin valves, which can be promising for technological applications. [ABSTRACT FROM AUTHOR]

The hexahydrate of europium nitrate hexahydrate Eu(NO)·6HO shows no phase transitions in the range of −40 to 76 °C when it melts in its own water of crystallization. It was shown that the thermal decomposition is a complex step-wise process, which starts with the simultaneous condensation of 6 mol of the initial monomer Eu(NO)·6HO into a cyclic cluster 6[Eu(NO)·6HO]. This hexamer gradually loses water and nitric acid, and a series of intermediate amorphous oxynitrates is formed. The removal of HNO azeotrope is essentially a continuous process occurring in the liquid phase. At higher temperatures, oxynitrates undergo further degradation, lose water, nitrogen dioxide, and oxygen, and finally, after having lost lattice water, are transformed into europium oxide. All mass losses are satisfactorily accounted for under the proposed scheme of thermal decomposition. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the administration of the follicle-stimulating hormone (FSH-p) or equine chorionic gonadotropin (eCG) in protocols of ovulation synchronization. One hundred forty-nine crossbred Holstein-Gyr cows were used in 2 properties in Minas Gerais and 3 treatments: TControl (n= 49 cows), Day 0: insert of a progesterone device (Primer®, Tecnopec, São Paulo, Brazil) + 2 mg of estradiol benzoate (RIC-BE®); Day 8: removal of Primer + 112 mg of D-cloprostenol (Prolise®, ARSA SRL, Buenos Aires, Argentina) + 1 mg of estradiol benzoate and fixed-time artificial insemination (FTAI) accomplished 44 h after the removal of Primer; TFSH (n= 50 cows), similar to TControl, but on Day 8, 15 mg of FSH-p (Folltropin®, Bioniche Animal Health) was administered; TeCG (n= 50 cows), similar to TControl, with administration on Day 8 of 300 IU of eCG (Novormon®, Syntex SA, Buenos Aires, Argentina). Cows that returned to estrus 14 to 28 days after the FTAI were inseminated once again. For all statistical analysis, we used the program SAS 9.0 (2002; SAS Institute Inc., Cary, NC, USA) at 5% probability. Quantitative variables (live weight, days postpartum, follicular average per cow) were analyzed by variance, and body condition score by Friedman test. The pregnancy rates were submitted to logistic analysis considering the effect of local experimental factors and were analyzed by Spearman correlation among the variables studied and the pregnancy rate. There was no difference (P> 0.05) between treatment for pregnancy rate in FTAI protocols (TControl = 40.82%; TFSH = 38.00%; TeCG = 26.00%), in the first insemination after FTAI (TControl = 56.25%; TFSH = 70.59%; TeCG = 68.42%), and in FTAI plus first insemination after FTAI (TControl = 59.18%; TFSH =62.00%; TeCG = 52.00%), as well as for the estrus repetition (TControl = 55.17%; TFSH = 54.84%; TeCG = 51.35%) and the correlation (P> 0.05) among the pregnancy rate and postpartum period, milk production, body weight and body condition. No effect was observed on the pregnancy rate by the addition of the hormones FSH and eCG in the protocol of ovulation synchronization in crossbred Holstein-Gyr cows; however, reinsemination in the period from 14 to 28 days after FTAI increased the pregnancy rate. CNPq; FAPEMIG; TECNOPEC/São Paulo, Brazil. [ABSTRACT FROM AUTHOR]

The importance of serum progesterone (P4) during the first weeks of pregnancy to reduce the embryo mortality in cattle herds has been demonstrated (Mann and Lamming 2001 Reproduction 121, 175-180). Studies show that a P4 peak at the beginning of pregnancy (about 5 days after the natural breeding or AI) helps development of the concept via secretion of interferon-τ (Mann 2002 XXII World Buiatrics Congress 18-23, 300-306). Studies have shown that the administration of gonadotropin-releasing hormone (GnRH) or its agonists after AI may stimulate corpus luteum function, induce the formation of an accessory corpus luteum, or increase of P4 serum concentrations and, therefore, improve embryonic survival (Bartolome et al.2005 Theriogenology 63, 1026-1037). This work aims to evaluate the effect of GnRH injection 12 d after fixed-time AI(FTAI) on P4 serum levels and pregnancy rate of beef crossbred cows. The cows (Bos taurus indicus× Bos taurus taurus, n= 59), range in body condition (BCS) from 2.5 to 3.5 (scale of 1 to 5), were not previously pregnant. The animals were allocated to 2 treatments: TEB treatment (n= 30) consisted of Day 0 insertion of progesterone intravaginal device (ID) plus 2 mg of estradiol benzoate (EB), i.m. followed on Day 8 by removal of the ID and 300 IU of eCG and 0.15 mg of PGF2α, i.m. on Day 9, 1 mg injection of EB (i.m.) was given, followed by FTAI at 48 to 56 h after the withdrawal of ID. The TEBGnRH12 treatment (n= 29) protocol was similar to TEB, but with administration of 25 μg of GnRH analogue (Lecirelina) 12 d after the FTAI. Transrectal ultrasound was used for pregnancy diagnosis on Day 35 after AI. Blood samples for P4 serum assay were collected from 30% of animals in each treatment, at the time of AI and on Days 5, 12, and 20 after FTAI. For all statistical analysis, we used the program SAS 9.0 (2002; SAS Institute Inc., Cary, NC, USA) at 5% probability. The pregnancy rate was analyzed by logistic regression. The effects of treatment and day in P4 concentration were analyzed in a split plot, with the effect of day in plot, in mixed model, considering the error and repetition as a random effect, and comparison of means by Tukey-Kramer. Pregnancy rate and the concentration of serum P4 on different days was analyzed by Spearman correlation. The pregnancy rate for TEB cows was 53.33% (16/30) for the first service compared with 37.93% (11/29) for TEBGnRH12 cows. The protocol used did not affect the pregnancy rate of crossbred cows (P> 0.05). There were no treatment differences (P> 0.05) between the concentrations of P4 (TEB = 3.88 ng mL-1; TEBGnRH12 = 3.12 ng mL-1). In conclusion, the administration of the analogue of GnRH 12 days after FTAI does not affect the rates of pregnancy or the concentration of P4. Supported by grants from CNPq, FAPEMIG and DZO-UFV. [ABSTRACT FROM AUTHOR]

The article presents study related to clinical care of men with HIV/AIDS. The core of people living with HIV/AIDS in Brazil, following guidelines issued by National Ministry of Health, has brought about a significant reduction in the morbidity and mortality associated with this retroviral infection. Patients were selected by consecutive sampling of those who recognised themselves as men who have sex with women (MSW) and answered a standardised questionnaire on disclosure of HIV diagnosis, health professionals' attitudes at time of diagnosis, clinical follow up, and use of antiretroviral therapy (ART).

The thermal decomposition of dysprosium nitrate is a complex process which begins with the simultaneous condensation of the initial monomer Dy(NO)·6HO into a cyclic hexamer 6[Dy(NO)·6HO]. This cluster gradually loses water and nitric acid, and intermediate oxynitrates DyO(NO)·6HO and DyO(NO)·5HO are formed. At higher temperatures, these products undergo further degradation, lose nitrogen dioxide, water, and oxygen, and finally, after having lost lattice water, are transformed into the cubic form of dysprosium oxide. The models of intermediate oxynitrates represent a reasonably good approximation to the real structures and a proper interpretation of experimental data. The comparison of the potential energies of consecutive oxynitrates permitted an evaluation of their stability. The mechanism was studied by thermal analysis, differential scanning calorimetry, infrared spectroscopy, and X-ray diffraction. The mass losses were related to the vibrational energy levels of the evolved gases. [ABSTRACT FROM AUTHOR]

Thermal decomposition of samarium nitrate hexahydrate Sm(NO)·6HO has been investigated by thermogravimetry, differential scanning calorimetry, infrared spectroscopy, and X-ray diffractometry. This is a complex process that involves slow dehydration and fast concomitant internal hydrolysis. It is markedly different from the processes described for other members of the lanthanide series. At the first stage, pyrolysis is accompanied by removal of water and nitric acid to form samarium pentahydrate Sm(NO)·5HO and intermediate oxonitrates containing O-Sm-OH groups. No traces of SmONO were detected. It is assumed that the existence of intermediate structures with six atoms of samarium best fits the experimental results. At higher temperatures, these products undergo further degradation, lose nitrogen dioxide, water, and oxygen, and finally, after having lost lattice water, are transformed into a cubic form of samarium oxide. [ABSTRACT FROM AUTHOR]

Limited information is available about the effect of mid-pregnancy viral infections on the placental expression of efflux transporters and offspring behavior. We hypothesized that maternal exposure to polyinosinic-polycytidylic acid [poly(I:C)], a synthetic double-stranded RNA viral mimic, would impair placental cell turnover, the expression of selected ABC transporters and adult offspring behavior. C57BL/6 mice were administered poly(I:C) (10 mg/Kg;ip) or vehicle at gestational day (GD) 13.5 (mid-pregnancy). Dams were euthanized for blood collection 4 h after injection, fetal and placental collection at GD18.5 or allowed to deliver spontaneously at term. At GD 13.5, poly(I:C) induced an acute pro-inflammatory response characterized by an increase in maternal plasma levels of IL-6, CXCL-1 and CCL-2/MCP-1. At GD 18.5, poly(I:C) decreased cell proliferation/death in the labyrinthine and increased cell death in the junctional zones, characterizing a disruption of placental cell turnover. Abca1 and Abcg1 immunolabelling was decreased in the labyrinthine zone, whereas Abca1, Abcg1 and breast cancer resistance transporter (Bcrp) expression increased in the junctional zone. Moreover, adult offspring showed motor and cognitive impairments in the Rotarod and T-water maze tests. These results indicate that viral infection during mid-pregnancy may disrupt relevant placental efflux transporters, as well as placental cell turnover and offspring behavior in adult life. [ABSTRACT FROM AUTHOR]

Sexual abuse leads to physical harm and devastating psychosocial consequences. It increases risk of HIV transmission and is associated with risky behaviour. Little is known about sexual abuse victimisation (SAV) and perpetration (SAP) among HIV-positive men who have sex with women (MSW). We investigated self-reported SAV and SAP among 242 Brazilian MSW selected at HIV care centres. Patients were questioned about sociodemographic data, mode of HIV acquisition, sexual practices, drug use and history of SAV or SAP. Prevalence of outcomes was estimated and risk factors for SAP investigated by logistic regression. Fifty-eight (24.1%) interviewees reported SAV. Of patients abused before 15 years of age, 64.3% reported events before the age of ten. Aggressors included relatives, friends and teachers. Among those victimised after 15 years old, 57.7% described events before 17 and 38.5% had acquainted aggressors. Fourteen (5.8%) interviewees reported SAP and most knew their victims. Sexual abuse perpetration was associated with lower schooling, marital status, illicit drug use and self-reported SAV. Sexual abuse was frequently reported by MSW from this cohort. Identifying predictors of violence and addressing SAV and SAP in comprehensive HIV care may help reduce violent behaviour, psychological distress and contribute to maximise benefits of preventive and care interventions. [ABSTRACT FROM AUTHOR]

Sexual abuse leads to physical harm and devastating psychosocial consequences. It increases risk of HIV transmission and is associated with risky behaviour. Little is known about sexual abuse victimisation (SAV) and perpetration (SAP) among HIV-positive men who have sex with women (MSW). We investigated self-reported SAV and SAP among 242 Brazilian MSW selected at HIV care centres. Patients were questioned about sociodemographic data, mode of HIV acquisition, sexual practices, drug use and history of SAV or SAP. Prevalence of outcomes was estimated and risk factors for SAP investigated by logistic regression. Fifty-eight (24.1%) interviewees reported SAV. Of patients abused before 15 years of age, 64.3% reported events before the age of ten. Aggressors included relatives, friends and teachers. Among those victimised after 15 years old, 57.7% described events before 17 and 38.5% had acquainted aggressors. Fourteen (5.8%) interviewees reported SAP and most knew their victims. Sexual abuse perpetration was associated with lower schooling, marital status, illicit drug use and self-reported SAV. Sexual abuse was frequently reported by MSW from this cohort. Identifying predictors of violence and addressing SAV and SAP in comprehensive HIV care may help reduce violent behaviour, psychological distress and contribute to maximise benefits of preventive and care interventions. [ABSTRACT FROM AUTHOR]

Mott transitions, which are metal-insulator transitions (MITs) driven by electron-electron interactions, are usually accompanied in bulk by structural phase transitions. In the layered perovskite Ca1.9Sr0.1RuO4, such a first-order Mott MIT occurs in the bulk at a temperature of 154 kelvin on cooling. In contrast, at the surface, an unusual inherent Mott MIT is observed at 130 kelvin, also on cooling but without a simultaneous lattice distortion. The broken translational symmetry at the surface causes a compressional stress that results in a 1500/o increase in the buckling of the Ca/Sr-O surface plane as compared to the bulk. The Ca/Sr ions are pulled toward the bulk, which stabilizes a phase more amenable to a Mott insulator ground state than does the bulk structure and also energetically prohibits the structural transition that accompanies the bulk MIT. [ABSTRACT FROM AUTHOR]

This paper presents a comparative study among three different formulations to analyse optical waveguides. All treatments, namely, full-vectorial, semi-vectorial, and scalar are based on the successive over relaxation-SOR technique. A complete expansion of these three formulations together with a convergence study of the respective iterative relaxation parameters are also provided. Several waveguiding structures are investigated in this work, including D-shaped fibres, rib waveguides, and photonic crystal fibres, addressing the accuracy of the several FD-SOR formulations implemented. It is demonstrated that the semi-vectorial approach produces excellent results when compared to those obtained with the full-vectorial treatment. Copyright © 2006 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This paper presents the first measurement of the elemental composition of the suspended particulate matter in the atmosphere of Londrina city (Paraná State, Brazil). The sampling was accomplished in the summer of 2003 and in the winter of 2002, with a stacker filter holder, collecting simultaneously the fine particulates (PM2.5) and the coarse particulates (PM10). The concentration of K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Br and Pb associated with particulate matter was determined by energy dispersive X-ray fluorescence. The results of the grouping analysis suggested that the elements in the aerosol particles came from two sources: soil re-suspension and industrial or anthropogenic activities. [ABSTRACT FROM AUTHOR]

Commercial poultry hatcheries provide ideal conditions for the multiplication and spread of microorganisms. Formaldehyde is widely used as a disinfectant; however, it is harmful to human health and can cause abnormal morphology in chicks. An alternative microbiological control is the use of copper, a metallic antimicrobial agent for contact surfaces. The antimicrobial efficacy of copper surfaces has been established in healthcare environments. However, its use in the poultry chain is still limited. This study aimed to compare the antimicrobial activity of common polypropylene hatch baskets with hatch baskets composed of copper (polypropylene hatch baskets covered by copper hatch baskets; polypropylene hatch baskets with solid copper plates on the bottom; polypropylene hatch baskets covered by copper hatch baskets and with solid copper plates on the bottom). To simulate a hatching environment with high contamination, the eggs and hatching cabinet were not fumigated. Microbiological analysis of the hatching cabinet environmental, surface of hatch basket, and fluff were performed. The results indicated that the absence of bottom holes resulted in a higher volume of organic matter that interfered with the copper's antimicrobial activity. The presence of copper in the hatch baskets did not decrease microbial contamination under the conditions evaluated, confirming that the metal should only be used as a complement to standard hygiene and not as a substitute for surface disinfectants. Further analysis will evaluate the antimicrobial activity of hatch baskets composed only of copper and the ability of nanoparticles to remove the biofilms formed by bacteria isolated from the poultry environment. [ABSTRACT FROM AUTHOR]

Magnetic properties of sputtered Gd thin films grown on Si (100) substrates kept at two different temperatures were investigated using X-ray diffraction, ac magnetic susceptibility, and dc magnetization measurements. The obtained Gd thin films have a mixture of hcp and fcc structures, but with their fractions depending on the substrate temperature TS and film thickness x. Gd fcc samples were obtained when TS = 763 K and x = 10 nm, while the hcp structure was stabilized for lower TS (300 K) and thicker film (20 nm). The fcc structure is formed on the Ta buffer layer, while the hcp phase grows on the fcc Gd layer as a consequence of the lattice relaxation process. Spin reorientation phenomenon, commonly found in bulk Gd species, was also observed in the hcp Gd thin film. This phenomenon is assumed to cause the magnetization anomalous increase observed below 50 K in stressed Gd films. Magnetic properties of fcc Gd thin films are: Curie temperature above 300 K, saturation magnetization value of about 175 emu/cm³, and coercive field of about 100 Oe at 300K; features that allow us to classify Gd thin films, with fcc structure, as a soft ferromagnetic material. [ABSTRACT FROM AUTHOR]

Virola surinamensis is a forest species widely distributed in the estuaries of the Amazon. These ecosystems are susceptible to contamination by Cadmium (Cd), indicating that the plant has strategies for tolerating this metal. The aim of this study was to assess the nitrogen and carbon metabolism of young plants of Ucuúba (Virola surinamensis) in the presence of cadmium with the perspective of the phytoremediation of contaminated environments. The used experimental design was a completely randomized design with five Cd concentrations (0, 15, 30, 45, and 60 mg L− 1), for 60 days. In general, Cd did not affect nitrate concentration in the root but had a positive effect on leaves. The reduction of nitrate reductase (NR) in plants exposed to Cd was followed by a decrease in ammonia, total soluble amino acids (TSA), and total soluble proteins (TSP). Cd promoted an increase in the concentration of total soluble carbohydrates (TSC), proline, sucrose, and reducing sugars in the plants. The increase in TSC, sucrose and proline, suggests a metabolic regulatory mechanism of V. surinamensis against Cd stress. [ABSTRACT FROM AUTHOR]

Virola surinamensis is a forest species widely distributed in the estuaries of the Amazon. These ecosystems are susceptible to contamination by Cadmium (Cd), indicating that the plant has strategies for tolerating this metal. The aim of this study was to assess the nitrogen and carbon metabolism of young plants of Ucuúba (Virola surinamensis) in the presence of cadmium with the perspective of the phytoremediation of contaminated environments. The used experimental design was a completely randomized design with five Cd concentrations (0, 15, 30, 45, and 60 mg L− 1), for 60 days. In general, Cd did not affect nitrate concentration in the root but had a positive effect on leaves. The reduction of nitrate reductase (NR) in plants exposed to Cd was followed by a decrease in ammonia, total soluble amino acids (TSA), and total soluble proteins (TSP). Cd promoted an increase in the concentration of total soluble carbohydrates (TSC), proline, sucrose, and reducing sugars in the plants. The increase in TSC, sucrose and proline, suggests a metabolic regulatory mechanism of V. surinamensis against Cd stress. [ABSTRACT FROM AUTHOR]

Virola surinamensis is a forest species widely distributed in the estuaries of the Amazon. These ecosystems are susceptible to contamination by Cadmium (Cd), indicating that the plant has strategies for tolerating this metal. The aim of this study was to assess the nitrogen and carbon metabolism of young plants of Ucuúba (Virola surinamensis) in the presence of cadmium with the perspective of the phytoremediation of contaminated environments. The used experimental design was a completely randomized design with five Cd concentrations (0, 15, 30, 45, and 60 mg L− 1), for 60 days. In general, Cd did not affect nitrate concentration in the root but had a positive effect on leaves. The reduction of nitrate reductase (NR) in plants exposed to Cd was followed by a decrease in ammonia, total soluble amino acids (TSA), and total soluble proteins (TSP). Cd promoted an increase in the concentration of total soluble carbohydrates (TSC), proline, sucrose, and reducing sugars in the plants. The increase in TSC, sucrose and proline, suggests a metabolic regulatory mechanism of V. surinamensis against Cd stress. [ABSTRACT FROM AUTHOR]

Gigahertz magnetoimpedance (MI) curves obtained in an exchange biased Ni81Fe19/Fe50Mn50 multilayer are reported. Experimental MI curves are shifted by the exchange bias field (HEB), following the features presented by the hysteresis curves. Theoretical MI curves, calculated using the classical expression for the impedance of a planar magnetic conductor, describe well the experimental data. The results open possibilities for application of exchanged biased MI multilayered materials for the development of autobiased linear magnetic field sensors. [ABSTRACT FROM AUTHOR]

We report studies by x-ray diffraction, ferromagnetic resonance (FMR), and x-ray magnetic circular dichroism (XMCD) in Co/Ru superlattices grown by magnetron sputtering. We studied the [Co(50 Å)/Ru(tRu)]20 samples, which were deposited at room temperature on Si substrates with the Ru thicknesses, tRu, varying between 9 and 33 Å. The main and secondary uniform absorption modes, observed in the FMR spectra, are associated with the Co/Ru interfaces and the bulk Co regions, respectively. The main mode becomes more intense than the secondary one for increasing tRu. This is attributed to the roughness and/or atomic interdiffusion, which leads, with increasing tRu, to an increasing volume of Co/Ru interfacial regions and a decreasing volume of pure Co regions. The XMCD measurements provide Co spin magnetic moments lower than the bulk Co value, confirming the presence of a Co magnetic region with a lower local effective magnetization attributed to the Co/Ru interfaces. [ABSTRACT FROM AUTHOR]

The magnetism at the interfacial regions of the [Fe(50 Å)/Cr(27 Å)]20 antiferromagnetic coupled multilayer was studied using the x-ray magnetic circular dichroism (XMCD) technique. Two experimental approaches were used to reach the interface regions. In the first one, multilayers of the same type, deposited with the Cr capping layer with different thicknesses of 30, 20, 10, and 5 Å, were analyzed and we obtained a magnetic depth profile without removing the layers. In the second approach, the layers of the sample were thinned by several in situ sputtering cycles with Ar+ ions, followed by XMCD analysis. We found a strong reduction of the Fe spin magnetic moments in the sputtered sample, which was caused by the erosion of the layers. On the contrary the noneroded samples kept the Fe bulk moment values. The observation of Cr XMCD signal evidenced an induced moment on Cr antiparallel to the Fe moments. [ABSTRACT FROM AUTHOR]

We have studied the influence of an inserted nano-oxide layer (NOL) on the interfacial magnetism in spin-valve systems showing the giant magnetoresistance effect. Specifically, we performed a magnetic depth profile of these structures with and without a NOL, using the x-ray magnetic circular dichroism technique. We found that insertion of a NOL into the spin-valve structure is correlated with a stronger reduction of the magnetic moments at the ferromagnetic (FM)/NOL/FM interface in comparison with a spin valve without NOL. [ABSTRACT FROM AUTHOR]

An efficient structure for spline-based fractional delay filtering for interpolation/decimation is introduced. Inspired by the Newton structures for Lagrange interpolation, it requires less than half the number of operations of a typical Farrow implementation. Moreover, it displays better frequency response characteristics than Lagrange-based filters. To obtain this structure, a matrix form of the Farrow transfer function is proposed and used to derive state-space transformations between the Lagrange-Farrow structure and its Newton counterpart. These transformations are then applied to the spline polynomial, giving rise to the efficient Newton-like spline filtering method. [ABSTRACT FROM AUTHOR]

A comparative ferromagnetic resonance (FMR) study of the magnetic properties of Si(100)[FeNi/Al/FeMn/Al]×10 and Si(100)[FeMn/Al(6 Å)/FeNi(30 Å)/Al]×20 multilayers is reported. Besides the uniform mode, the parallel and perpendicular FMR spectra of both multilayers also give evidence of additional magnetic phases in the films. The perpendicular FMR spectrum of the first multilayer also shows the presence of a volume spin-wave resonance (SWR) mode, while the spectrum of the second shows the presence of a surface SWR mode. This is attributed to the structural differences between the two multilayers in terms of the thicknesses of the magnetic (FeNi) and nonmagnetic (FeMn and Al) layers. [ABSTRACT FROM AUTHOR]

1. The aim of the present study was to determine if the 9R-strain of the Salmonella Gallinarum live vaccine was responsible for having fowl typhoid outbreaks in chicken flocks from both chicken and turkey breeders as well as to verify the antimicrobial resistance of the isolates from the outbreaks. 2. The triplex polymerase chain reaction, standard antimicrobial test, beta-lactamase genes identification and Ion Torrent PMG whole-genome sequence were used in the field isolates and in the vaccine strain of S. Gallinarum. 3. The 60 tested isolates were not from vaccine origin and manifested high resistance to drugs from macrolide and quinolone groups. Whole-genome sequencing (WGS) and single nucleotide polymorphism analysis on selected isolates for core genes from Salmonella enterica confirmed the wild origin of these isolates and showed two possible sources of S. Gallinarum in the studied outbreaks. 4. S. Gallinarum isolated from fowl typhoid outbreaks in the studied period were not caused by the use of the SG9R live vaccine. The source of strains sequenced was diverse. [ABSTRACT FROM AUTHOR]