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Highlights • High and room temperature structural evolution is scanned. • Electrical, mechanical and magnetic properties are measured simultaneously. • Only one sample test is employed for the whole structural evolution study. • Evolution curves present a great level of detail. • A great amount of useful data for the design are obtained with a single experiment. Abstract The structure evolution of some soft magnetic metastables alloys are scanned and studied through some room temperature properties changes employing only one sample submitted to successive heat treatments. These are monitored by changes occurring in room temperature magnetic properties (data obtained from hysteresis loop at 50 Hz and relative permeability at 10 kHz), room and high temperature electrical resistance and dilatometric measurements, all taken simultaneously. The method is applied to study and compare the structural evolution steps towards the most desirable soft magnetic properties of three different soft magnetic alloys of our production: an amorphous alloy of composition Fe 81 B 14 Si 5 , and two nanocrystalline, a Finemet™ (Fe 73.5 Si 16.5 B 6 Cu 1 Nb 3) and a Nanomet™ (Fe 81 Si 6 P 4 Cu 1 B 8) – type alloys. The technique reproduces the results obtained by traditional methods, and has the advantage of using fewer measuring instruments, sample tests, less time and human resources. In addition, all the experimental data present a high level of detail. With the results obtained, a large quantity of magnetic, electrical and dilatometric data is available to discern the possible applications of these three materials. [ABSTRACT FROM AUTHOR]

A method for calculating saturation magnetostriction values in solid-solution ternary alloys is proposed using the magnetostriction data of binary alloys implicated in the ternary system and few data of ternary alloy. Studies on three systems are presented: the Fe-Al-Si system where a considerable magnetostriction data available in the literature was employed to perform the method; the Fe-Al-Ge system in which our data are compared and discussed with a previous study in this system; and the Fe-Ge-Si system for which iso-magnetostriction curves are proposed since only one experimental value in the literature was found. The results obtained by this method approximate previously reported experimental data. This can be used to design alloys with a defined value of magnetostriction reducing the number of samples and measurements or in calculations on theoretical models. In this sense, a hypothetical behaviour of magnetostriction in the Fe-Ge binary system for Ge > 20 at.%. is also presented. [ABSTRACT FROM AUTHOR]

A new type of study is presented for magnetic and structural characterization of amorphous or nanocrystalline metallic alloys in ribbon or wire-shaped samples. A single sample is subjecting to successive steps of flash isocurrent heat treatments with increasing duration in time, followed by a rapid cooling, while magneto-electric properties evolution are scanned in situ at room temperature. When one set of isocurrent heat treatments is finished, the annealing current is increased and a new set of isocurrent treatments starts. The properties studied were the saturation magnetization and the coercive field at 50 Hz, magnetic permeability at 100 kHz and electrical resistance from where we also obtained the crystalline fraction. The method was applied on two samples of Finemet-like alloys and the results were analyzed from the perspective of current literature. With the present method it is possible to obtain a general and meticulous understanding of the structural and magnetic evolution of the samples tested, with a considerable saving of time and samples. [ABSTRACT FROM AUTHOR]

This paper proposes to see the way to integrate recommendations and direct experiences into reputational images as a planning problem. Specifically we achieve this goal through a combination of a fuzzy cognitive map and probabilistic planning with RDDL. Both were implemented inside a deliberative agent architecture that intends to appropriately represent the uncertain nature of data (with a Markov decision process) and the involved deliberative reasoning (with a fuzzy cognitive map). We are interested in the viability of using this view so it was tested by the simulations inspired in the ART testbed domain, but our final intention is proposing an alternative and richer representation of concepts involved in reputation problems instead of increasing the accuracy of trust predictions at any cost. [ABSTRACT FROM AUTHOR]

Background and objective Meaningful targeting of brain structures is required in a number of experimental designs in neuroscience. Current technological developments as high density electrode arrays for parallel electrophysiological recordings and optogenetic tools that allow fine control of activity in specific cell populations provide powerful tools to investigate brain physio-pathology. However, to extract the maximum yield from these fine developments, increased precision, reproducibility and cost-efficiency in experimental procedures is also required. Methods We introduce here a framework based on magnetic resonance imaging (MRI) and digitized brain atlases to produce customizable 3D-environments for brain navigation. It allows the use of individualized anatomical and/or functional information from multiple MRI modalities to assist experimental neurosurgery planning and in vivo tissue processing. Results As a proof of concept we show three examples of experimental designs facilitated by the presented framework, with extraordinary applicability in neuroscience. Conclusions The obtained results illustrate its feasibility for identifying and selecting functionally and/or anatomically connected neuronal population in vivo and directing electrode implantations to targeted nodes in the intricate system of brain networks. [ABSTRACT FROM AUTHOR]

Charts containing lattice parameters of Fe 1 − x (M,N) x ternary systems with M and N = Si, Al, Ge or Co, and 0 ⩽ x ⩽ ∼0.3, were developed by implementing a linear relationship between the respective binary alloys with the same solute content of the ternary one. Charts were validated with experimental data obtained from literature. For the Fe–Co–Si system, the linear relationship does not fit the experimental data. For the other systems (except the Fe–Co–Ge one where no experimental data was found), the lineal relationship constitute a very good approximation. Using these charts and the lattice parameter data obtained from X-ray diffraction technique combining with the solute content data obtained from Mössbauer spectroscopy technique it is possible to determine the chemical composition of nanograins in soft magnetic nanocomposite materials and some examples are provided. [ABSTRACT FROM AUTHOR]

Much of our understanding of the neuronal mechanisms of spatial navigation is derived from chronic recordings in rodents in which head-direction, place, and grid cells have all been described. However, despite the proposed importance of self-reference information to these internal representations of space, their congruence with vestibular signaling remains unclear. Here we have undertaken brain-wide functional mapping using both fMRI and electrophysiological methods to directly determine the spatial extent, strength, and time course of vestibular signaling across the rat forebrain. We find distributed activity throughout thalamic, limbic, and particularly primary sensory cortical areas in addition to known head-direction pathways. We also observe activation of frontal regions, including infralimbic and cingulate cortices, indicating integration of vestibular information throughout functionally diverse cortical regions. These whole-brain activity maps therefore suggest a widespread contribution of vestibular signaling to a self-centered framework for multimodal sensorimotor integration in support of movement planning, execution, spatial navigation, and autonomic responses to gravito-inertial changes. [ABSTRACT FROM AUTHOR]

Abstract: Development of thermal energy storage (TES) systems for concentrated solar power (CSP) is essential in order to match a variable electricity demand with an intermittent energy source supply, enhancing energy generation dispatchability. The high energy storage densities and the possibility of working at higher temperature ranges make thermochemical heat storage (TCS) via reduction–oxidation (redox) cycles of metal oxides a promising concept for energy storage. For this purpose, manganese and cobalt oxides have been selected as feasible candidates due to their favourable thermodynamic properties. In order to explore the potential of these materials, the capacity of both pure (Mn2O3 and Co3O4) and mixed oxides (Mn3−x Co x O4) to withstand several charge–discharge cycles was evaluated by thermogravimetrical analysis. Results showed better cyclability for the mixed oxides with low Mn content (x≥2.94) and, specially, for the corresponding pure oxides, confirming that these materials may be a viable option for TCS. [Copyright &y& Elsevier]

Magnetic properties of some nanocrystalline soft magnetic alloys are evaluated by means of a model obtained from literature. The influence of alloy elements in grain diameter, crystalline fraction and anisotropies are investigated in order to obtain information for the design of nanocrystalline soft magnetic materials. The study concerns materials with nanocrystalline composition of Fe, Fe-Si, Fe-Si-Al, and Fe-Ge, and is complemented with alloys containing nanocrystals of Fe and Fe-Co from literature. Results indicate that the reduction of grain diameter in Fe-based nanocrystal alloys is the main challenge to enhance the soft magnetic properties, when induced anisotropies are suppressed. For Fe-(Si,Al,Ge)-based nanocrystals, it is necessary to obtain a good balance of the magnetoelastic anisotropies. This can be achieved by modifying the amount of crystallized fraction via changes in the chemical composition of the nanocrystals and/or the matrix. In the case of Fe-Co, magnetic softness is attained by decreasing the Co content or with the addition of elements like Si or Al. [ABSTRACT FROM PUBLISHER]

Hydroxyectoine overproduction by the natural producer Chromohalobacter salexigens is presented in this study. Genetically engineered strains were constructed that at low salinity coexpressed, in a vector derived from a native plasmid, the ectoine (ectABC) and hydroxyectoine (ectD) genes under the control of the ectA promoter, in a temperature-independent manner. Hydroxyectoine production was further improved by increasing the copies of ectD and using a C. salexigens genetic background unable to synthesize ectoines. [ABSTRACT FROM AUTHOR]

This paper presents the statistical analysis of an experimental high-resolution sea-clutter database, collected with a high-resolution Ka-band radar at the south coast of Spain. The main motivation of this paper has been to check the validity of the available theoretical models for high-resolution sea-clutter against data corresponding to a range resolution of centimeters. The overall amplitude probability density function (pdf), the compatibility with a compound representation, and the average spectral behavior of the data are analyzed in detail. Results clearly show the suitability of the compound Gaussian model and, more precisely, that the empirical pdf is well modeled by the generalized K distribution with log-normal texture. A close agreement has also been found between the estimated clutter spectral density and a power-law model. [ABSTRACT FROM AUTHOR]

Background: Osmosensing and associated signal transduction pathways have not yet been described in obligately halophilic bacteria. Chromohalobacter salexigens is a halophilic bacterium with a broad range of salt tolerance. In response to osmotic stress, it synthesizes and accumulates large amounts of the compatible solutes ectoine and hydroxyectoine. In a previous work, we showed that ectoines can be also accumulated upon transport from the external medium, and that they can be used as carbon sources at optimal, but not at low salinity. This was related to an insufficient ectoine(s) transport under these conditions. Results: A C. salexigens Tn1732-induced mutant (CHR95) showed a delayed growth with glucose at low and optimal salinities, could not grow at high salinity, and was able to use ectoines as carbon sources at low salinity. CHR95 was affected in the transport and/or metabolism of glucose, and showed a deregulated ectoine uptake at any salinity, but it was not affected in ectoine metabolism. Transposon insertion in CHR95 caused deletion of three genes, Csal0865-Csal0867: acs, encoding an acetyl-CoA synthase, mntR, encoding a transcriptional regulator of the DtxR/MntR family, and eupR, encoding a putative two-component response regulator with a LuxR_C-like DNAbinding helix-turn-helix domain. A single mntR mutant was sensitive to manganese, suggesting that mntR encodes a manganese-dependent transcriptional regulator. Deletion of eupR led to salt-sensitivity and enabled the mutant strain to use ectoines as carbon source at low salinity. Domain analysis included EupR as a member of the NarL/ FixJ family of two component response regulators. Finally, the protein encoded by Csal869, located three genes downstream of eupR was suggested to be the cognate histidine kinase of EupR. This protein was predicted to be a hybrid histidine kinase with one transmembrane and one cytoplasmic sensor domain. Conclusions: This work represents the first example of the involvement of a two-component response regulator in the osmoadaptation of a true halophilic bacterium. Our results pave the way to the elucidation of the signal transduction pathway involved in the control of ectoine transport in C. salexigens. [ABSTRACT FROM AUTHOR]

FINEMET type ribbons (Fe73.5Si13.5Nb3 − xMoxB9Cu1, x = 1.5, 2 at.%) were produced by the planar flow casting technique and subsequently heat treated at 823 K to induce nanocrystallization and to optimize its soft magnetic properties. The coercivity, measured by conventional fluxmetric method, resulted in HC = 0.53 ±0.10 and 0.41±0.05 A/m for x = 1.5 and 2 respectively. A correlation between magnetic properties and the amorphous and nanocrystalline phases when Nb was partially substituted with Mo was studied by means of Mössbauer spectroscopy and X-ray diffraction. [ABSTRACT FROM AUTHOR]

The development of bulk metallic glasses (BMGs) is a topic of current interest due to the unique set of properties that distinguish them from their crystalline counterpart and make them attractive in industrial applications as both structural and functional materials. Currently, a great effort is being made to model and quantify the glass forming ability of the amorphous in an alloy, as well as in tuning their properties in view of the final application of the material. In this work we have used two machine learning techniques, multiple linear regression and tree boosting, to predict the maximum amorphous diameter of Fe-based BMGs, exclusively from the alloy's chemical composition. The modeĺs predictive power is characterised by a predicted-R2 of 0.71 (predicted-R = 0.84) and a training-R2 of 0.90 (training-R = 0.95) over a set of 480 alloys present in the dataset. Learning curves are employed as part of a comparative prediction analysis of the two techniques and to help decide the modelling aspects on which effort should be invested in the future. Selected examples using pseudo-ternary diagrams for the design of new Fe-based BMGs are presented, where the potential of the model becomes clear. [ABSTRACT FROM AUTHOR]

To improve the thermochemical energy storage (TCS) behavior of Mn2O3, several Mn–Mo oxides with varying amounts of MoO3 (0–30 wt%) were prepared by a precipitation method. The physico-chemical properties of the solids were studied by N2 adsorption–desorption, X-ray diffraction (XRD), scanning electron microscopy (SEM), and H2-temperature-programmed reduction (TPR), while their TCS behavior was determined by thermogravimetric analysis coupled with differential scanning calorimetry (TGA-DSC). Apart from Mn2O3 and MoO3 phases, XRD revealed a mixed MnMoO4 phase for MoO3 loadings equal or higher than 1.5 wt%. All samples showed a well-formed coral-like surface morphology, particularly those solids with low MoO3 contents. This coral morphology was progressively decorated with compact and Mo-enriched MnMoO4 particles as the MoO3 content increased. TPR revealed that the redox behavior of Mn2O3 was significantly altered upon addition of Mo. The TCS behavior of Mn2O3 (mostly oxidation kinetics and redox cyclability) was enhanced by addition of low amounts of Mo (0.6 and 1.5% MoO3) without significantly increasing the reduction temperature of the solids. The coral morphology (which facilitated oxygen diffusion) and a smoother transition from the reduced to oxidized phase were suggested to be responsible for this improved TCS behavior. The samples containing 0.6 and 1.5 wt% of MoO3 showed outstanding cyclability after 45 consecutive reduction–oxidation cycles at high temperatures (600–1000 °C). These materials could potentially reach absorption efficiencies higher than 90% at concentration capacity values typical of concentrated solar power plants. [ABSTRACT FROM AUTHOR]

• Nanomet alloy is nanocrystallized by current annealings. • Pulses of annealing currents were used in one of the cases. • A continuous increase in the annealing current was used in the other case. • With the pulses of currents it was possible to study the structural evolution. • The best magnetic properties were obtained with a heating rate calculated at 15 K/s. Nanocrystallization of an Fe 85.2 Si 0.5 B 9.5 P 4 Cu 0.8 alloy was induced by two different types of heat treatments employing Joule heating technique. In one case, continuous pulses of increasing amplitude of annealing current are supplied on a single sample, while in the other case, constant increases of the annealing current are used on different samples. The results show that with the first type of experiment it is possible to study the structural evolution of the alloy, providing that the amplitude of the pulse remains less than a maximum value. With the second type of experiments we have obtained the maximum value of heating rate for our system to achieve the nanocrystallization of the magnetically soft phase and avoiding the precipitation of phases that deteriorate the magnetic properties. The soft magnetic properties obtained with the second type of heat treatment are similar to those obtained in the literature with other types of thermal treatments. The work also presents measurements of electrical resistance and dilatometry during the structural evolution of the studied alloy. [ABSTRACT FROM AUTHOR]

This paper presents the results of an extensive experimental parametric analysis of coherent radar detectors exploiting a new Ka-band high-resolution sea-clutter database. The statistical analysis of the submeter range resolution real data shows strong fluctuations of both the spectral shape and power between adjacent range cells. This highly heterogeneous dataset is therefore ideally suited to characterize the performance degradation to be expected in real conditions, relative to the homogeneous finite-sample-support case. The impact of spectral heterogeneity within the reference window of the detectors is quantified by resorting to simulated datafiles. The analysis focuses on both the experimental constant false alarm rate (CFAR) behavior and the synthetic Swerling I target probability of detection. Finally, a comparison with a practical detection scheme is included, allowing the trade-off between increased computational complexity and improvement in performance over conventional approaches to be assessed. [ABSTRACT FROM PUBLISHER]

This study analizes the psychometric properties of a new instrument about the working model of children's attachment. The sample was composed of 60 subjects (30 from normal population and 30 from a social risk population). The age of children ranges from 3 to 7 years old. This instrument is an interview based on the completion story task, however it includes new contents as well as a new procedure in regarding to previous attachment measures. The findings show good validity and reliability. The found results are going to be the beginning of future studies. [ABSTRACT FROM AUTHOR]

The article focuses on the possible changes in the microbial etiology and prognosis of late-onset prosthetic valve endocarditis associated with hospital-acquired infections. Infectious endocarditis is a changing disease with predisposing risk factors, etiology, manifestations and therapeutics in continuous evolution. Although recognized for almost 30 years, invasive medical technology has been associated with an increasing number of cases of infectious endocarditis, and there is evidence that hospital-acquired endocarditis not associated with cardiac surgery is on the rise.

Background. Coinfection with hepatitis C virus (HCV) and human immunodeficiency virus (HIV) is a known risk factor for hepatotoxicity in patients receiving highly active antiretroviral therapy (HAART). The aim of this study was to evaluate the role of HCV-related liver fibrosis in HAART-associated hepatotoxicity. Methods. In a prospective study involving 107 patients who underwent liver biopsy, fibrosis was graded according 5 stages, from FO (no fibrosis) to F4 (cirrhosis). Hepatotoxicity was defined as an increase in levels of aspartate aminotransferase and alanine aminotransferase to >5 times the upper limit of normal, or a >3.5-fold increase if baseline levels were abnormal. The incidence of hepatotoxicity was compared with liver fibrosis stage and with time and composition of HAART. Results. Overall, 27 patients (25%) had hepatotoxic events (5.1 events/100 person-years of therapy). The incidence was greater for patients with stage F3 or F4 fibrosis (3 8%) than for those with stage Fl or F2 fibrosis (15%; 7.6 vs. 3 events/100 person-years; relative risk, 2.75; 95% confidence interval, 1.08-6.97; P = .013). Duration of HCV infection, duration of HAART, diagnosis of acquired immunodeficiency syndrome, HCV load, HCV genotype, and nadir CD4+ cell count did not affect the risk of hepatotoxicity. Of the 86 patients who received nonnucleoside reverse- transcriptase inhibitors (NNRTIs), 11(13%) developed liver toxicity. In these patients, fibrosis stages Fl and F2 were associated with similar rates of toxicity (3 events/100 person-years for patients who received nevirapine, 3.3 events! 100 person-years for those who received efavirenz, and 3.4 events!100 person-years for those who received non- NNRTIs). There was a greater incidence among patients with F3 or F4 fibrosis who received NNRTIs (11.7 events! 100 person-years for patients who received nevirapine, and 8.6 events!100 person-years for those who received efavirenz), compared with those who received non-NNRTIs (4 events!100 person-years). Conclusions. HAART-associated hepatotoxicity correlates with liver histological stage in patients coinfected with HIV and HCV. There was no difference in hepatotoxicity risk for different antiretroviral therapies in patients with mild-to-moderate fibrosis. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs) and long noncoding RNAs (lncRNAs) are two relevant non-coding RNAs (ncRNAs) class. Oncorhynchus kisutch (coho salmon) is an important aquaculture pacific salmon species without report of miRNAs and a very limited register of lncRNAs. To gain knowledge about the interaction and discovery of miRNAs and lncRNAs in coho salmon we used high-throughput sequencing technology to sequence small and transcriptome libraries from three immune organs. A total of 163 mature miRNAs and 4,975 lncRNAs were discovered. The profiles of expression of both ncRNAs indicated that liver and head-kidney share relatively similar expression patterns. We identified 814 and 181 putative target sequences for 1048 lncRNAs and 47 miRNAs, respectively. The results obtained provide new information and enlarge our understanding of the diversities of ncRNAs in coho salmon. • This is first report of miRNAs in coho salmon. • 4,975 lncRNAs and 163 mature miRNAs were identified in three normal immune organs of coho salmon. • Both ncRNAs showed that liver and head-kidney organs share relatively similar expression patterns. • Our results showed that 1,339 lncRNAs will be the potential target of 148 miRNAs. • Therefore, these results will support the hypothesis of lncRNA sponge or competing endogenous RNA in coho salmon. [ABSTRACT FROM AUTHOR]

The productivity of the mining industry in Chile, currently the main driver of Chilean economy, is closely tied to foreign demand for ores. Ore-processing is known for involving energy–intensive processes, such as comminution, concentrating and cathodic processes. As mining activities take place in the arid north of Chile, they are affected by water scarcity. Water shortage has forced the industry to pump desalinated seawater up to mining sites over 2000 m above sea level, further increasing electricity consumption. Given these energy needs, and the fact that electrical energy supply in the north of Chile is based on fossil fuels, it is important to consider the use of renewable energies as environment-friendly and economic alternatives. The aim of this work is to evaluate, by an optimized techno-economic analysis, the use of photovoltaic and a novel wind-based technology to supply at least 10% of the current and the predicted electrical energy requirements of the mining industry in the Antofagasta region. A combination of an optimization problem and technical evaluation was performed using Matlab to obtain the optimal number of solar and wind-based technology units in a case study. Total energy generation from a novel wind-based technology unit is 67,616 MWh/y, corresponding to 14.45·10 6 Nm 3 (1298 t) of hydrogen and 7.41·10 6 Nm 3 (10,323 t) of oxygen after electrolytical transformation. Considering a 65% efficiency of the combined cycle fed with hydrogen and oxygen, 28,133 MWh/y of electrical energy would be obtained. For the cases studied the cost of energy from the combined system was estimated to be between 0.255 US$/kWh and 0.273 US$/kWh, slightly higher than the average energy regional cost. According to the analysis, the renewable energy system could be a sustainable alternative to supply economic green energy to the mining industry in Chile. [ABSTRACT FROM AUTHOR]

The disaccharide trehalose is considered as a universal stress molecule, protecting cells and biomolecules from injuries imposed by high osmolarity, heat, oxidation, desiccation and freezing. Chromohalobacter salexigens is a halophilic and extremely halotolerant c-proteobacterium of the family Halomonadaceae. In this work, we have investigated the role of trehalose as a protectant against salinity, temperature and desiccation in C. salexigens. A mutant deficient in the trehalose-6- phosphate synthase gene (otsA::V) was not affected in its salt or heat tolerance, but double mutants ectoine- and trehalosedeficient, or hydroxyectoine-reduced and trehalose-deficient, displayed an osmo- and thermosensitive phenotype, respectively. This suggests a role of trehalose as a secondary solute involved in osmo- (at least at low salinity) and thermoprotection of C. salexigens. Interestingly, trehalose synthesis was osmoregulated at the transcriptional level, and thermoregulated at the post-transcriptional level, suggesting that C. salexigens cells need to be pre-conditioned by osmotic stress, in order to be able to quickly synthesize trehalose in response to heat stress. C. salexigens was more sensitive to desiccation than E. coli and desiccation tolerance was slightly improved when cells were grown at high temperature. Under these conditions, single mutants affected in the synthesis of trehalose or hydroxyectoine were more sensitive to desiccation than the wild-type strain. However, given the low survival rates of the wild type, the involvement of trehalose and hydroxyectoine in C. salexigens response to desiccation could not be firmly established. [ABSTRACT FROM AUTHOR]

Abstract: Prosthetic heart valve thrombosis is a serious complication with a high mortality. We report the case of a thrombosed St Jude Medical valve placed in the pulmonary position, in a patient who had undergone repair of tetralogy of Fallot, which was successfully treated with intravenous thrombolytic therapy with streptokinase. [Copyright &y& Elsevier]

The consistent interest in supporting research and development of magnetic materials during the last century is revealed in their steadily increasing market. In this work, the soft magnetic nanocrystalline FINEMET alloy was prepared with commercial purity raw materials and compared for the first time with the generally studied high purity one. The exhaustive characterization covers several diverse techniques: X-ray diffraction, Mössbauer spectroscopy, differential scanning calorimetry, differential thermal analysis and magnetic properties. In addition, a brief economic analysis is presented. For the alloys annealed at 813 K, the value of the grain size was 16 nm with 19·5% of Si, the coercivity was 0·30 A m while the saturation was 1·2 T. These results prove that structural, magnetic and thermal properties of this material are very close to the expensive high purity FINEMET alloy, while a cost reduction of almost 98% seems highly attractive for laboratories and industry. The analysis should be useful not only for the production of FINEMETs, but for other type of systems with similar constitutive elements as well, including soft and hard magnetic materials. [ABSTRACT FROM AUTHOR]

Abstract: A comprehensive analysis of magnetoimpedance phenomena in Finemet-type as spun ribbons with a Cu–Co layer electrodeposited at different currents is presented here as a function of microstructure. The measurements were performed in moderate and high frequencies (30kHz–6GHz) under an axial magnetic field, up to 25kA/m. The magnetoimpedance variations have been studied by measuring the reflection parameter S 11 of a coaxial line containing the magnetic sample by means of a vector network analyzer. The GMI vs applied field curve does not show a monotonic decay but displays a maximum. GMI first increases with frequencies up to ∼10MHz reaching values of ΔZ/Z max ∼20%. At higher frequencies the GMI ratio is seen to decrease becoming vanishingly small at ∼1GHz. [Copyright &y& Elsevier]

Over the last years new radar systems uses have been arisen, both civil and military field. These further uses demand more data about the radar targets. Up to now, was enough to know its location, rough velocity and an approximate motion direction, even though, now there is a growing need of security and control, which requires higher accuracy measuring these targets's characteristics, even to obtain a "radar image" trying to classify or identify it. This article explains how to obtain ISAR radar images, especially using a Continuous Wave Linear Frequency Modulated Radar (CWLFM), not only in a theoretical way but also showing the results achieved in a lot of different experiments made during a four years research-project sponsored by the Spanish Ministry of Science and Technology, emphasizing the high quality of the images obtained, and also, that any kind of control or collaboration was expected from the target. Making the result more important from a practical point of view, opening up much more possible applications to radar systems. [ABSTRACT FROM AUTHOR]

Chromohalobacter salexigens, a Gammaproteobacterium belonging to the family Halomonadaceae, shows a broad salinity range for growth. Osmoprotection is achieved by the accumulation of compatible solutes either by transport (betaine, choline) or synthesis (mainly ectoine and hydroxyectoine). Ectoines can play additional roles as nutrients and, in the case of hydroxyectoine, in thermotolerance. A supplementary solute, trehalose, not present in cells grown at 37°C, is accumulated at higher temperatures, suggesting its involvement in the response to heat stress. Trehalose is also accumulated at 37°C in ectoine-deficient mutants, indicating that ectoines suppress trehalose synthesis in the wild-type strain. The genes for ectoine (ectABC) and hydroxyectoine (ectD, ectE) production are arranged in three different clusters within the C. salexigens chromosome. In order to cope with changing environment, C. salexigens regulates its cytoplasmic pool of ectoines by a number of mechanisms that we have started to elucidate. This is a highly complex process because (i) hydroxyectoine can be synthesized by other enzymes different to EctD (ii) ectoines can be catabolized to serve as nutrients, (iii) the involvement of several transcriptional regulators (sS, s32, Fur, EctR) and hence different signal transduction pathways, and (iv) the existence of post-trancriptional control mechanisms. In this review we summarize our present knowledge on the physiology and genetics of the processes allowing C. salexigens to cope with osmotic stress and high temperature, with emphasis on the transcriptional regulation. [ABSTRACT FROM AUTHOR]

Objective: To validate a questionnaire to identify psychosocial repercussions of the lipodystrophy syndrome (LD) in HIV-infected patients.Methods: A questionnaire containing 35 items in 6 subscales [body image, anxiety, depression, social support, social distress, quality of life (QoL)] was consecutively administered to 128 patients with LD, 25 naive patients or on therapy without LD, and to 15 HIV negative patients from January to July '04. Reliability was assessed using Cronbach's alpha and the intraclass correlation coefficient (ICC). The area under the curve (AUC) was used for discrimination between patients and control groups, and the scores were compared according to the severity of the LD.Results: In all the subscales, the relationship between higher scores and LD severity was statistically significant (0.37-0.64, p<0.01), whereas the control groups had significantly lower scores. The internal consistency showed Cronbach's alpha coefficients ranging from 0.64 to 0.93. Test-retest reliability after 15 days in 30 patients showed ICC values of 0.8-0.94. AUC values for the different subscales were higher than 0.7 with the exception of QoL score, and construct validity showed a significant correlation with the Beck Depression Inventory and the MOS-HIV scores (0.49 and 0.51, respectively, p<0.01).Conclusions: Our questionnaire shows satisfactory psychometric properties for identifying psychosocial repercussions of the LD in HIV-infected patients. [ABSTRACT FROM AUTHOR]