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This research reports the synthesis, characterization, and electrical properties of the systems EryCe1−yO2−δ(y= 0.05, 0.1, and 0.15), and the effect of the incorporation of sintering aids (2 wt.% of CaO, MgO, and TiO2) on the electrical properties of the composition Er0.1Ce0.9O1.95, to be used as ceramic solid electrolytes in low-temperature solid oxide fuel cells (LT-SOFC). All EryCe1−yO2−δsamples were obtained by mechanochemistry (20 h of milling) and characterized by XRD. The morphology of the pure sintered compositions and with the incorporation of sintering aids (sintered at 1200 °C) was evaluated by FE-SEM. Electrical properties as a function of temperature (200–650 °C) and frequency (100 Hz–1 MHz) were evaluated by impedance spectroscopy. It reveals an increase of bulk ionic conductivity for higher contents of Er, as the number of oxygen vacancies increases. The higher value of conductivity (6.7 × 10–3S cm−1) at 650 °C was for the composition Er0.15Ce0.85O1.925, while the ionic conductivity of Er0.1Ce0.9O1.95at 650 °C increased from 2.68 × 10–3S cm−1to a maximum of 1.54 × 10–2S cm−1with the incorporation of CaO as additive. These improvements in bulk ionic conductivities can contribute to the development of more efficient electrolytes for the LT-SOFC technology.

Radioecological models used to make predictions of the radionuclide activity concentrations in human foodstuffs must be sufficiently robust and fit for purpose with uncertainties reduced where practicable. The CONFIDENCE project had a work package with the objective to improve the capabilities of radioecological models and this paper presents the key findings of this work. Recommendations for future radioecological studies/model developments are made based on the findings of the work conducted and consultations with end-users.

AISI-420 martensitic steel is used in several applications due to its high corrosion resistance. A niobium nitride coating is deposited on steel by cathodic cage plasma deposition (CCPD) to upgrade the surface properties. The X-ray diffraction shows that the coating has a tetragonal Nb4N5structure in each condition. The nano-hardness of the untreated sample (2.5 GPa) is increased up to 15.5 and 18.7 GPa at 400°C and 450°C, respectively. A ball-on-disc wear tester is applied for wear analysis, and the wear rate is found to be reduced up to six times by coating. This study shows that the CCPD can be used successfully for depositing niobium nitride coating with outstanding mechanical and tribological properties of AISI-420 steel.

The influence of pulse time tp variation on hardness, crystalline phases and electrochemical corrosion susceptibility of plasma nitriding 316L was investigated. Hardness test, X-ray diffraction, scanning electron microscopy and electrochemical polarisation tests let to identify the best processing conditions. Nitriding at tp5 ms in a 100 Hz discharge increased the 316L hardness around four times and decreased its corrosion susceptibility one order of magnitude. The X-ray diffraction analysis showed the shifted reflections for the expanded austenite and let to identify an anisotropic strain with expansion lattice around 7·5 and 9 for 111 and 200 orientations respectively. For the evaluated tprange, the increase in the pulse length has not beneficial influence on surface hardness; on the contrary, there is a decrease in its value when tpgrew from 5 to 8 ms. Corrosion and hardness performance has been related to the strain level and to the nitrogen content.

The Spanish Quality Assurance Program applied to the process of donation after brain death entails an internal stage consisting of a continuous clinical chart review of deaths in critical care units (CCUs) performed by transplant coordinators and periodical external audits to selected centers. This paper describes the methodology and provides the most relevant results of this program, with information analyzed from 206,345 CCU deaths. According to the internal audit, 2.3% of hospital deaths and 12.4% of CCU deaths in Spain yield potential donors (clinical criteria consistent with brain death). Out of the potential donors, 54.6% become actual donors, 26% are lost due to medical unsuitability, 13.3% due to refusals to donation, 3.1% due to maintenance problems and 3% due to other reasons. Although the national pool of potential donors after brain death has progressively decreased from 65.2 per million population (pmp) in 2001 to 49 pmp in 2010, the number of actual donors after brain death has remained at about 30 pmp. External audits reveal that the number of actual donors could be 21.6% higher if all potential donors were identified and preventable losses avoided. We encourage other countries to develop similar comprehensive approaches to deceased donation performance.

Background: Treatment with GH promotes linear growth and decreases body fat in patients with isolated GH deficiency (GHD). However, few studies have analyzed how GH replacement modifies ghrelin levels and the adipokine profile and the relationship of these modifications with the metabolic changes. Aims: To analyze the eventual differences between serum levels of leptin, leptin soluble receptor (sOBR), resistin, adiponectin, interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), otal (TG) and acylated ghrelin (AG) and lipid and glycemic profiles in children with GHD, as well as to determine the effect of GH replacement on these parameters during the first year of therapy. Subjects and methods: Thirty pre-pubertal (Tanner stage I) GHD children and 30 matched controls were enrolled. Children with GHD were studied before and after 6 and 12 months of GH treatment. Weight, height, BMI, fasting glucose, insulin, lipid profile and serum levels of adipokines and ghrelin were studied at every visit. Adipokines, insulin and ghrelin levels were determined by using commercial radio- and enzymoimmunoassays. Results: At baseline children with GHD had significantly higher sO-BR (p<0.01) and adiponectin (p<0.01) levels than controls. Treatment with GH resulted in a decline in leptin (p<0.05) and TG (p<0.001) levels, an increase of homeostasis model assessment index and restored IGF-I levels (p<0.001). Conclusions: These data indicate that GH replacement has a negative effect on leptin levels and may also produce a slight unfavorable effect on carbohydrate metabolism. In addition, the changes observed in the adipokine profile appear to be independent of body mass index.

Countermeasures to reduce the transfer of a radionuclide from soil to plants are usually based on saturating the soil with a stable element that is a chemical analogue of that radionuclide. But when a radioactive contamination event occurs, it is seldom due to the evacuation of a pure radionuclide such as 137Cs. Instead, a mixture of radionuclides may be released into the environment. The countermeasures applied to reduce the transfer of one of them may also influence other radionuclides. We have developed an experimental procedure to check whether radiocaesium countermeasures are appropriate when other radionuclides are also involved, or have some disadvantages that may limit their use. It consists of growing wheat seeds under controlled laboratory conditions using Neubauer's plantlet method. This method has been in use for many years as a small-scale screening procedure to check a soil's capacity to provide the potassium that plants need as a nutrient. In particular, we used it to study the effectiveness and the disadvantages of the application of a potassium salt fertilizer to a soil contaminated with 134Cs, 90Sr, and 60Co. This countermeasure indeed reduced the uptake of 134Cs, but it also enhanced the uptake of 60Co. This enhancement was higher for the wheat stems than for the roots. For 90Sr, there was observed a slight increase due to the fertilizer.

Fungi have up to now generally been used as bioindicators of radiocaesium in terrestrial ecosystems. However there is little knowledge about the behaviour of other man-made radionuclides. In the present work, we analyzed the soil-to-fungi transfer of 90Sr, 239+240Pu, and 241Am by collecting several species of fungi and the corresponding surface soil (0−5 cm) of a selected semi-natural ecosystem. The transfer of these radionuclides was then quantified by means of the traditional transfer factor, TF, defined as the ratio between the content in the fruiting bodies and in the total fraction of soil. As a general rule, the 90Sr TF values were higher than those of 239+240Pu and 241Am. This definition of the transfer factor can underestimate the transfer of radionuclides of which a large percentage are bound to soil particles. We therefore also used a definition based on the amount of radionuclide available to be transferred instead of the total content of the soil — the available transfer factor, ATF — which would be closer to the actual process of transfer. Hebeloma cylindrosporumand Lycoperdon perlatumpresented 239+240Pu and 241Am ATF values that were greater than or similar to those of 90Sr. These species may thus be used as bioindicators for 239+240Pu and 241Am in a forest ecosystem.

It is well known that the bioavailability of artifical radionuclides such as 90Sr, 137Cs and 239+240Pu in contaminated soils depends on the source term origin of the contamination. Altough the behaviour of the mentioned radionuclides in the soil is also influenced by the time passed from the contamination event and the characteristics of the contamination receiving soils. The objective of the present work is to analyse the different bioavailability and possible chemical-physical associations of 90Sr, 137Cs, and 239+240Pu in soils located in different Spanish ecosystems (Almeria and Cáceres provinces) by application of a sequential extraction procedure based on the NIST standard sequential extraction protocol. The resulting fractions obtained are: a) water soluble and exchangeable, b) associated to organic matter, and c) residual fraction. They will be studied jointly with the polluting sources (deposit of nuclear fallout-50s and 60s, Palomares accident in 1966 and the cesium release by Acerinox in 1998) in each ecosystem to interpret the observed behaviour of radionuclides.

Field studies have shown that the uptake of radionuclides by fungi depends on its nutritional mechanism (mycorrhizal or saprophytic), but this fact is only fully demonstrated for radiocaesium. To extend this conclusion to other radionuclides likely to be released in semi-natural ecosystems, we carried out a series of experiments under controlled laboratory conditions of the growth of mycelium of mycorrhizal and saprophytic fungi (Pleurotus eryngiiand Hebeloma cylindrosporumrespectively) on liquid culture media containing known added activities of 60Co, 85Sr, and 134Cs. The radionuclide incorporated most efficiently into Pleurotus eryngiiwas 134Cs, and into Hebeloma cylindrosporumwas 60Co. For 134Cs and 85Sr, we also analysed the influence that the content of the chemically analogue elements K and Ca respectively in the culture medium had on its uptake. For both species, the uptake of 134Cs is not correlated with the content of K in the media, but it is the uptake of 85Sr increasing with it. These results seem to be independent of the nutritional mechanism. The influence of linearity in the uptake of 134Cs and 85Sr with increasing concentrations of Cs and Sr in the culture medium was also studied. For Pleurotus eryngiiit was observed a decrease in the uptake of 134Cs with increasing Cs content in the medium, and an increase in the uptake of 85Sr with increasing Sr content in the medium.

This paper investigates the effect of varying cooling rate on the mechanical properties of a novel fibre metal laminate based on glass-fibre polypropylene. Differential scanning calorimetry (DSC) and polarised light microscopy have been used to identify differences in the matrix morphology resulting from varying the processing conditions. Additionally, the residual stresses in simple bi-material samples manufactured under different cooling conditions were quantified in order to understand the effect of the cooling rate on the mechanical properties of these multilayered materials. The results indicate that the residual stresses were greater in the fast cooled samples, whereas the degree of crystallinity was higher in slow cooled samples.The results highlight a strong link between processing conditions and mechanical properties under both fibre and matrix-dominated modes of loading. The flexural properties of the plain composites and the fibre-metal laminates were greater at the low cooling rates. Conversely, the tensile strength and interlaminar toughness for both types of material were greater for specimens manufactured using high cooling rates. Finally, faster cooling was shown to yield laminates with a superior impact resistance. It is believed that the rapid cooling of the laminates enhanced their resistance to interlaminar fracture, which in turn resulted in smaller damage areas after impact.

A thorough discussion of perturbative QCD for twist-4 is presented from a practical point of view. Misleading uses of intrinsic transverse momentum and mass terms are criticized and corrected in the complete expressions relevant for a model-independent experimental test of power corrections which is proposed. Upper and lower bounds for the twist-4 scale are deduced from a theoretically-consistent analysis of present DIS data with a simplified assumption on twist-4, from which a power-dominatedR=sL/R=sT is predicted.

Creutzfeldt-Jakob Disease (CJD), an invariably fatal dementing illness, affects patients in middle and old age (sporadic form). However, the association of CJD with certain treatments (iatrogenic form) has been described in younger patients. The clinical onset of the two forms seems to differ; in the iatrogenic form a high frequency of the ataxic CJD variant has been reported. Nowadays, a definitive diagnosis of CJD is exclusively histological. We present five cases of CJD, one sporadic and the others iatrogenic, following dura mater grafts and analyse their CT and MRI features. CT typically demonstrates brain atrophy, generally progressive, but in sporadic CJD midfield MRI also showed abnormal signal, with predominant deep grey matter involvement. The use of narrow windows with proton-density sequences may reveal subtle cortical signal abnormalities not clearly visible with conventional windows. The early demonstration of these changes, in the appropriate clinical context, may suggest CJD and this supports the use of mid- or high magnetic fields in the diagnosis of CJD and other forms of dementia. In our cases of iatrogenic CJD, low-field MRI did not reveal more than the progressive atrophy displayed by CT, and raises the question on the one hand of possible differences, based on imaging, from the sporadic form, and on the other of the lack of sensitivity of low-field magnets to signal changes in CJD.

Control of Frankliniella occidentalis (Pergande) is a serious problem for agriculture all over the world because of the limited range of insecticides that are available. Insecticide resistance in F. occidentalis has been reported for all major insecticide groups. Our previous studies showed that cytochrome P450-mediated detoxification is a major mechanism responsible for insecticide resistance in this pest. Degenerate polymerase chain reaction was used to identify P450 genes that might be involved in acrinathrin resistance, in a laboratory population of F. occidentalis. Associated sequences were classified as belonging to the CYP4 and CYP6 families. Real-time quantitative polymerase chain reaction analyses revealed that two genes, CYP6EB1 and CYP6EC1, were over-expressed in adults and L2 larvae of the resistant population, when compared with the susceptible population, suggesting their possible involvement in resistance to acrinathrin.

Nineteen Macaca fascicularis monkeys were divided into four different groups: Group A (n = 3), control; Group B (n = 3), monkeys treated with I-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP); Group C (n = 8), animals treated with MPTP in which the subthalamic nucleus (STN) was unilaterally lesioned by kainic acid injection; in Group D (n = 5), the STN was lesioned prior to MPTP administration. Subthalamotomy resulted in a bilateral improvement of tremor, spontaneous activity, bradykinesia (evaluated by a manual motor test) and freezing in Group C. All these monkeys developed hemichorea contralateral to the lesion. The improvement was maintained and the hemichorea continued until death. The monkeys in group D showed severe hemiballism which persisted throughout MPTP administration and developed parkinsonian signs mainly on the side ipsilateral to the lesion. Analysis of the in situ hybridization of the mRNA coding for glutamic acid decarboxylase (GAD) of MPTP monkeys showed a significant increase in the mean density of silver grains over every labelled neuron in the globus pallidum lateralis (56.8% over control) as well as the globus pallidus medialis (GPM) (45.7% over control) and the substantia nigra reticulata (SNR) (35.8% over control). No significant change was observed in the thalamic nucleus reticularis. Subthalamotomy (Groups C and D) produced a significant reduction in mRNA GAD expression on the side of the lesion in the GPM and the SNR (34% and 42.3%, respectively) with respect to the ipsilateral (non-lesioned) side and also when compared with parkinsonian monkeys. These results confirm and expand, at the cellular level, the paramount role of STN hyperactivity in the pathophysiology of parkinsonism. The therapeutic consequences of these findings for surgical treatment of Parkinsons disease are discussed.

We report the results of a large scale (5 orchards) and long-term (5 yr) study on seasonal population fluctuationsof Anastrepha fruit flies in commercial mango orchards in the Soconusco Region, Chiapas, Mexico. Out of 10 Anastrepha species present in these orchards, West Indian fruit fly, A. obliqua (Macquart), and Mexican fruit fly, A ludens (Loew), accounted for 96.6% of all individuals captured in McPhail traps. A obliqua was by far the dominant species, accounting for 66.1% of all individuals captured. Anastrepha populations fluctuated markedly from year to year during our study. Furthermore, even though we worked in orchards that were relatively close to each other, we discovered significant differences in terms of total numbers of flies captured per orchard and Anastrepha species diversity in each orchard. Most flies (62.3%) were captured in traps placed in the periphery of orchards (i.e., edge traps). Also, most (≈90%) of the mangoes sampled in commercial orchards were infested by A. obliqua, despite the fact that significant numbers of A ludens adults were present in every orchard. In contrast, mangoes sampled at higher elevations were predominantly infested by A. ludens. We compare our results with similar studies in other parts of Mexico and Latin America and discuss our findings in light of their practical implications.

In this paper we present a paradigmatic tight-binding model for single-layer as well as multilayered semiconducting MoS2 and similar transition metal dichalcogenides. We show that the electronic properties of multilayer systems can be reproduced in terms of a tight-binding modeling of the single-layer hopping terms by simply adding the proper interlayer hoppings ruled by the chalcogenide atoms. We show that such a tight-binding model makes it possible to understand and control in a natural way the transition between a direct-gap band structure, in single-layer systems, and an indirect gap in multilayer compounds in terms of a momentum/orbital selective interlayer splitting of the relevant valence and conduction bands. The model represents also a suitable playground to investigate in an analytical way strain and finite-size effects. [ABSTRACT FROM AUTHOR]