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The objective of this study was to use tri-axial accelerometers to quantify circadian changes in the locomotor activity of 3 strains of laying hens. Animals were from either the White, Brown or Black strain of a farm that breeds free-range laying hens. Hens were fitted with commercially available sensors that record high resolution raw acceleration data, which were attached to the back of the hen by nylon harnesses and remained in place for 7 d. Separately, animals from each of the strains were allocated to an indoor hen house (density = 0.5 m2/hen), which had an artificial photoperiod (16L:8D), and an adjacent outdoor pen (4 m2). Minute-by-minute activity data values (Vector Magnitude, VM) were calculated from the activity counts of each of the 3 axes. Mean (± S.E.) activity (counts/min) of the White strain (was significantly (P< 0.001) higher than that of the other 2 strains. Hens were quiet in the dark period of the day, and were significantly (P< 0.001) more active in the light period. Locomotor activity differed significantly (P<0.001) among strains in both the dark and the light periods. All hens exhibited a 24-h circadian rhythm in activity, and significantly different MESOR and acrophases (P< 0.001). In conclusion, the tri-axial accelerometers tested in this study were useful for measuring locomotor activity in laying hens, and the animals adapted quickly to wearing the devices attached to harnesses. Hens from the 3 strains exhibited the same pattern in locomotor activity throughout the day, although they differed in the intensity of their activity

World events will be held in Spain in 1992 and economic reforms that would lead to economic development will be instituted. Despite allegations that Spain's legal aspect of corporations is still developing, the country expects to be able to catch up with the global business market. Developments to this effect are the recent legal institution of the policies on corporate entities on Jan 1, 1990 and the laws on mergers and acquisitions on Jan 1989.

Supported vanadium-containing hexagonal tungsten bronzes (HTBs) were prepared for the first time using a combination of a new soft synthetic procedure and fine-tuned heat treatments. The characterization of heat-treated samples indicates that both unsupported and Al2O3-supported materials present mainly vanadium-containing crystals with HTB structure smaller in the supported materials. Raman, diffuse reflectance UV-visible and EPR spectroscopic results suggest the presence of different V species depending on the V loading and catalyst composition. When used as catalysts for ethane oxidative dehydrogenation (ODH), selected supported vanadium-HTBs show selectivity to ethylene as high as 80% at ethane conversion of around 18%. These values position these new materials among the most active and selective catalysts so far reported in the literature for ethane ODH over supported vanadium oxide catalysts.

This paper presents trace element compositions and lead isotope analyses by MC-ICP-MS of 34 copper ore samples from the Internal Zone of the Betic Range, Southeast Spain. Samples were collected during a fieldwork campaign in the mines of Cerro Minado, Pinar de Bédar, Sierra Cabrera and Sierra Almagrera/Herrerías. Most samples are copper oxide minerals from the near surface alteration of the sulfide ore deposits. The aim of the study is to supplement the existing reference data bank on lead isotopic compositions of ancient copper mines from the Iberian Peninsula, complementing this data with trace element compositions. The latter can be useful for discriminating when isotopic overlaps occur. This characterisation will be of great usefulness for provenancing further archaeological materials. Lead isotope ratios range from 18.603 to 20.327 (206Pb/204Pb); from 15.685 to 15.779 (207Pb/204Pb) and from 38.728 to 39.702 (208Pb/204Pb). Data from the literature analysed by TIMS have been also considered for comparison although the larger analytical error is highlighted, especially for isotope 204Pb. The lead isotopic signature of the analysed samples shows three separate isotopic fields. These fields are also consistent with differences in compositions evidenced by principal component analyses.

Yellow rust is a wheat disease caused by Puccinia striiformis, this pathogen causes economic losses in susceptible materials, which represent up to 70% of wheat varieties. Currently, the incorporation of genetic resistance through molecular tools, is a process used in the generation of new varieties resistant to this pathogen. A strategy employed to identify genes involved in the resistance to yellow rust is to screen differential EST obtained by suppressive subtractive hybridization. In this research, cDNA was extracted from healthy and inoculated plants from the resistant line V-26 from INIFAP. A set of 200 differentially expressed EST were cloned and sequenced, and 31 of them were selected for expression profile analysis by RT-PCR; additionally, with the aim of validate RT-PCR results, five genes were selected for RT-qPCR analysis in genotypes inoculated by P. striiformis. The results showed high levels of expression of selected genes in genotypes classified as resistant in the field conditions (21, 143, 230, 242, 261 and 277), while in the susceptible genotype 16, few genes were induced by the rust. Expression profiles confirmed significant differences between resistant and susceptible lines.

NiO and metal-promoted NiO catalysts (M-NiO, with a M/(M+Ni) atomic ratio of 0.08, with M = Nb, Sn, or La) have been prepared, tested in the oxidative dehydrogenation (ODH) of ethane, and characterized by means of XRD, TPR, HRTEM, Raman, XPS, and in situ XAS (using H2/He, air or C2H6/He mixtures). The selectivity to ethylene during the ODH of ethane decreases according to the following trend: Nb–NiO ≈ Sn–NiO > La–NiO > NiO, whereas the catalyst reducibility (determined by both TPR and XAS using H2/He mixtures) shows the opposite trend. However, different reducibility and catalytic behavior in the absence of oxygen (ethane/He mixtures) have been observed, especially when comparing Nb- and Sn-promoted NiO samples. These differences can be ascribed mainly to a different phase distribution of the promoter. The results presented here are discussed in terms of the nature of active and selective sites for ODH of ethane in selective and unselective catalysts, but also the role of promoters and the importance of their phase distribution.

A variety of abnormalities in cytokine production occur in human and murine lupus, but their specific role in lupus pathogenesis is unknown. (1) Recent in vitro studies emphasise the role [...]

In this work, CaO-NiO mixed oxide powders were evaluated as consecutive CO2chemisorbents and catalytic materials for hydrogen production thought the CH4reforming process. Between the NiO-impregnated CaO and CaONiO mechanical composite, the first one presented better chemical behaviors during the CO2capture and CH4reforming processes, obtaining syngas (H2 + CO) as final product. Results showed that syngas was produced at two different temperature ranges, between 400 and 600 °C and at T > 800 °C, where the first temperature range corresponds to the CH4reforming process but the second temperature range was attributed to a different catalytic reaction process: CH4partial oxidation. These results were confirmed through different isothermal and cyclic experiments as well as by XRD analysis of the final catalytic products, where the nickel reduction was evidenced. Moreover, when a COO2flow was used during the carbonation process a triple process was achieved: (i) CO oxidation, (ii) CO2chemisorption and (iii) CH4reforming. Using this gas flow the hydrogen production was always higher than that obtained with CO2.

The influence of synthesis and post-synthesis procedures of different niobium oxides on their catalytic performance in the aqueous phase condensation of oxygenated compounds is studied. Hydrothermally synthesized niobium oxide with a pseudo-crystalline structure shows enhanced acid properties, surface area and consequently better catalytic activity than Nb2O5prepared by other synthesis methods. The optimized NbOx-based catalyst also demonstrates higher stability after several reuses compared to the Ce–Zr mixed oxide reference catalyst.

AbstractWe explain in some detail the geometric structure of spheres in any dimension. Our approach may be helpful for other homogeneous spaces (with other signatures) such as the de Sitter and anti-de Sitter spaces. We apply the procedure to the recently proposed division-algebras/Poincaré-conjecture correspondence. Moreover, we explore the possibility of a connection between N-qubit system and the Hopf maps. We also discuss the possible links of our work with squashed-spheres in supergravity and pseudo-spheres in oriented matroid theory.

APCVD of boro-phospho silicate glass from mixtures of TEOS, TMB and TMP, has been analysed then modelled in a continuous reactor. A reduced chemical mechanism has been developed and the corresponding rate constants have been identified. The first results obtained are encouraging and suggest that the very simple gas phase chemistry selected could be precise enough to represent the main trends of this very complex deposition procedure.

APCVD of boro-phospho silicate glass from mixtures of TEOS, TMB and TMPihas been analysed then modelled in a continuous reactor. A reduced chemical mechanism has been developed and the corresponding rate constants have been identified. The first results obtained are encouraging and suggest that the very simple gas phase chernistry selected could be precise enough to represent the main trends of this very complex deposition procedure.

Porous clay heterostructures (PCH) have shown to be highly efficient supports for nickel oxide in the oxidative dehydrogenation of ethane. Thus NiO supported on silica with a PCH structure shows productivity towards ethylene three times higher than if NiO is supported on a conventional silica. This enhanced productivity is due to the increase in the catalytic activity and especially to the drastic increase in the selectivity to ethylene. Additionally, PCH silica partially modified with titanium in the columns (PCH-Ti) have also been synthesized and used as supports for NiO. An enhanced activity and selectivity to ethylene was found over NiO supported over PCH-Ti compared to the corresponding catalysts supported over the Ti-free PCH. The enhanced catalytic performance has been related to the high dispersion of nickel oxide particles on the support, which leads to a lower reducibility of the nickel oxide, hindering the oxidation of ethane into carbon oxides. More interestingly, the particle morphology plays an important role on the catalyst selectivity since a higher distortion of the NiO crystal lattice parameter meant an enhanced selectivity to ethylene.

Minor histocompatibility Ags (mHags) have been implicated in the pathogenesis of GVHD after allogeneic hematopoietic stem cell transplantation (HSCT). Uridine diphospho-glucuronosyltransferase 2B17 (UGT2B17) gene deletion may act as a mHag and its association with acute GVHD (aGVHD) has been described. We retrospectively studied the clinical impact of a UGT2B17 mismatch in a cohort of 1127 patients receiving a HSCT from an HLA-identical sibling donor. UGT2B17 mismatch was present in 69 cases (6.1%). Incidence of severe aGVHD was higher in the UGT2B17 mismatched pairs (22.7% vs 14.6%), but this difference was not statistically significant (P: 0.098). We did not detect differences in chronic GVHD, overall survival, relapse-free survival, transplant-related mortality or relapse. Nevertheless, when we analyzed only those patients receiving grafts from a male donor (616 cases), aGVHD was significantly higher in the UGT2B17 mismatched group (25.1% vs 12.8%; P: 0.005) and this association was confirmed by the multivariate analysis (P: 0.043; hazard ratio: 2.16, 95% confidence interval: 1.03–4.57). Overall survival was worse for patients mismatched for UGT2B17 (P: 0.005). We conclude that UGT2B17 mismatch has a negative clinical impact in allogeneic HSCT from HLA-identical sibling donors only when a male donor is used. These results should be confirmed by other studies.

The deposition of silicon dioxide by Atmospheric Pressure Chemical Vapor Deposition using TEOS/Ozone chemistry in an industrial linear-injector reactor has been modeled. The objective was to optimize the operating conditions. ESTET, a French commercial CFD software, has been used to solve the hydrodynamics and heat transport problems. The software has been modified to take into account mass transport and chemical reactions both in the gas phase and on surfaces. Thus, the model enables us to predict the deposition rate and the operating conditions influences. The first results obtained will be discussed and compared with experimental data. The shields in the deposition chambers appear to play an important role in avoiding recirculation regions, and then minimizing undesirable risks of homogeneous nucleation and particle formation. Important thermal gradients are localized in a thin thermal boundary layer near the hot wafer surface. Deposition is mainly due to intermediate species produced by oxidation of TEOS in the gas phase. Some discrepancies remain between experimental and simulation results : at this time, they can be attributed to uncertainties in the chemical model used, which has not been established in exact industrial conditions.

Twenty-five dogs (beagles) were infected with Leishmania infantumby the intradermal inoculation of an estimated 5-8,000 metacyclic promastigotes harvested from the midguts of 320 experimentally infected P. perniciosus. Details are given of the methods of infecting the flies and harvesting the parasites. All dogs developed small, self-healing chancres at the sites of inoculation. Parasites were isolated from lymph nodes, bone marrow or spleen of 21 dogs, 12 of which developed signs of disease and raised IFAT titres to Leishmania. Nine of the 21 remained healthy over a fiveyear observation period. Six of the nine were shown to have a cell mediated immune response to Leishmania. No parasites were isolated from four of the 25 dogs, two of which had a demonstrable cell mediated immunity and another had low transitory IFAT titres. The fourth had chancres at the sites of inoculation. The results show that dogs can be readily infected with promastigotes from the midguts of sandflies. However, a high proportion develop a cell mediated immunity and show no signs of disease. It is suggested that serological surveys of dogs for canine leishmaniasis reveal neither the true prevalence of infection nor the intensity of transmission. The efficacy of controlling human visceral leishmaniasis caused by L. infantumby destroying seropositive dogs is questioned.

We present the results of an isophotal shape analysis of three samples of galaxies in the Coma cluster. Quantitative morphology, together with structural and photometric parameters, is given for each galaxy. Special emphasis has been placed on the detailed classification of early-type galaxies. The three samples are: i) a sample of 97 early-type galaxies brighter than mB= 17.00 falling within one degree from the center of the Coma cluster; these galaxies were observed with CCD cameras, mostly in good to excellent resolution conditions; ii) a magnitude complete sample of 107 galaxies of all morphological types down to mB= 17.00 falling in a circular region of 50 arcmin diameter, slightly offcentered to the North-West of the cluster center; the images for this and the next sample come from digitized photographic plates; iii) a complete comparison sample of 26 galaxies of all morphological types down to mR= 16.05 (or mB$\simeq$17.5), also in a region of 50 arcmin diameter, but centered 2.6 degrees West of the cluster center. The reliability of our morphological classifications and structural parameters of galaxies, down to the adopted magnitude limits, is assessed by comparing the results on those galaxies for which we had images taken with different instrumentation and/or seeing conditions, and by comparing our results with similar data from other observers.

El propósito de este estudio es valorar la necesidad de bloquear distalmente los clavos Gamma 3 (Stryker. Mahwah, New Jersey. USA) en fracturas pertrocantéreas de fémur 31-A1 y 31-A2 de la AO.

Recurrence of idiopathic focal segmental glomerulosclerosis (FSGS) following kidney transplantation occurs in a large percentage of patients. Accurate prediction of recurrence and elucidation of its pathogenesis are major therapeutic goals. To detect differential proteins related to FSGS recurrence, proteomic analysis was performed on plasma and urine samples from 35 transplanted idiopathic FSGS patients, divided into relapsing and nonrelapsing. Several proteins were detected increased in urine of relapsing FSGS patients, including a high molecular weight form of apolipoprotein A‐I, named ApoA‐Ib, found exclusively in relapsing patients. This finding was verified by Western blot individually in the 35 patients and validated in an independent group of 40 patients with relapsing or nonrelapsing FSGS, plus two additional groups: FSGS‐unrelated patients showing different proteinuria levels (n = 30), and familial FSGS transplanted patients (n = 14). In the total of 119 patients studied, the ApoA‐Ib form was detected in 13 of the 14 relapsing FSGS patients, and in one of the 61 nonrelapsing patients. Only one of the 30 patients with FSGS‐unrelated proteinuria tested positive for ApoA‐Ib, and was not detected in familial patients. Urinary ApoA‐Ib is associated with relapses in idiopathic FSGS and warrants additional investigation to determine its usefulness as biomarker of relapse following transplantation.

AbstractWe review remarkable results in several mathematical scenarios, including graph theory, division algebras, cross product formalism and matroid theory. Specifically, we mention the following subjects: (1) the Euler relation in graph theory, and its higher-dimensional generalization, (2) the dimensional theorem for division algebras and in particular the Hurwitz theorem for normed division algebras, (3) the vector cross product dimensional possibilities, (4) some theorems for graphs and matroids. Our main goal is to motivate a possible research work in these four topics, putting special interest in their possible links

Los marcadores séricos son de gran utilidad como indicadores de enfermedad celíaca (EC), si bien la biopsia intestinal sigue siendo el patrón oro para establecer el diagnóstico. La positividad de los anticuerpos antitransglutaminasa tisular humana de clase IgA (AATGt-IgA) y los anticuerpos antiendomisio IgA (AAE-IgA) se correlaciona con histología intestinal patológica. La atrofia vellositaria (Marsh 3) representa una característica fundamental para el diagnóstico de EC. El tipo correspondiente a Marsh 2 (hiperplasia críptica) es debatido como lesión propia de la EC.

Sodium zirconate (Na2ZrO3) was synthesized by a solid-state reaction and then it was tested in the methane reforming process. Na2ZrO3was initially carbonated at different temperatures (550–700 °C). Then, each carbonated Na2ZrO3sample (composed by Na2CO3and ZrO2) was used as a catalyst and as a carbon dioxide supplier for syngas (H2+ CO) production through the methane reforming reaction. Results clearly show the formation of H2and CO, evidencing a catalytic conversion. Moreover, cyclic and structural analyses corroborated that Na2ZrO3could be used cyclically in the carbonation and subsequent methane reforming processes, although the crystalline structure was not totally recovered.

The influence of Al and Al-Si coatings on the corrosion behaviour of HCM12 in molten KCl-ZnCl2 mixture at 650ºC in air has been characterized by electrochemical impedance spectroscopy (EIS). Al and Al/Si protective coatings were developed by chemical vapour deposition in fluidized bed reactor (CVD-FBR) at moderate temperature to respect to mechanical properties of substrate. Scanning electron microscopy (SEM) was used to analyse the damage on the HCM12 electrode surface. Al-Si coating was found to be more resistant to the molten chlorides attack than Al coating; and both coatings increased the corrosion resistance of HCM12 in these conditions. The surface composition has been determined by X-ray diffraction (XRD).

Summary:In order to further evaluate the potential of FT‐IR spectroscopic investigations on molecular processes during tensile testing experiments, the behavior of monolayer LLDPE films, made with ethylene‐butene and ethylene‐octene copolymers, was studied. Additionally, multilayer LLDPE films based on the same C4 and C8 copolymers were investigated. The stress‐strain data obtained from the monolayer films indicate differences in the strain hardening region. It seems that the film samples PE 469‐30‐2 (C4‐gas phase process) and PE 469‐30‐5 (C8 solution process) behave similarly whereas the strain hardening for the PE 469‐30‐3 (C4 solution process) requires lower stress values. The orientation function changes during the stretching of the films indicating that unfolding of the polymer chains occurs at lower strain for PE 469‐30‐5 (C8) than in the C4 materials. In the multilayer systems the Primplast 44 material (C8) shows a lower tendency for reorientation in the strain hardening region than the Coex 82 (C4) material. In this region of the stress‐strain curve the lamellar structure is already transformed into the fibrillar arrangement. Regarding the orientation behavior of the material above 200% strain, a small increase in fbwas observed, which led to a decrease of fc. In the octene product possibly the bulky side chains influence the unfolding significantly, producing a higher resistance to unfolding and alignment along the stretching direction. In part, this is potentially caused by the more perfect lamellae in the octene copolymer, which do not include the side chains, while the butene copolymer may have weaker lamellae because they contain a fraction of the side chains which create defects. Consequently, the octene copolymer requires higher stress values to be stretched and finally results in a lower stretchability of this material, as observed on an industrial scale during pallet wrapping tests. Based on the ratio of the structural absorbance parameters of the signals at 729 and 719 cm−1changes in the crystallinity were studied. For the continuous stretching experiment, no monoclinic phase was detected even after Fourier self‐deconvolution and peak fitting approaches. Literature data, however, describe that this crystalline transformation takes place as a result of mechanical deformation. Therefore, stepwise stretching experiments which allow an improvement of the spectral resolution to 1 cm−1were carried out. In the deconvoluted spectra the monoclinic, orthorhombic and amorphous LLDPE modifications could be assigned. Ultimate stretchability and stretching force of the films, both monolayer and multilayer, was well correlated to the development of crystalline orientation in the films upon stretching. Other mechanical properties like Elmendorf tear and dart impact can also be better understood with these results.

A young male Bernese mountain dog presented with neurologic abnormalities consisting of nonambulatory tetraparesis, generalized tremors, and depressed mental status. At necropsy only a mild enlargement of the lateral ventricles was seen. The histologic examination revealed the presence of eosinophilic deposits consistent with Rosenthal fibers (RFs) throughout the white matter of the central nervous system. There was also a marked proliferation of abnormally large astrocytes and limited myelin changes. RFs were most prominent in perivascular, subpial, and subependymal areas, where they were perpendicularly located, producing a pallisaded arrangement. immunohistochemically, RFs were strongly positive for glial fibrillary acidic protein (GFAP), and when they were examined ultrastructurally they appeared as electron-dense amorphous masses located within the processes of astrocytes, most particularly in the perivascular feet. The histologic and immunohistochemical findings of this canine case were consistent with the published neuropathologic descriptions of Alexander disease in humans and in a few dogs, a rare condition that in humans has been shown to be caused by dominant mutations in the GFAP gene.

An epidemiological cohort study of Enteromyxum scophthalmi in cultured turbot was performed on a farm in North Western Spain. Four different ongrowing stocks (A, B, C, D) were monitored monthly until market size. Fish from stocks C and D were divided into 2 subgroups, receiving filtered (CF and DF) or unfiltered (CUF and DUF) water. The lack of water filtration was positively associated with infection prevalence, as all fish kept in filtered water remained uninfected. Parasite abundance varied seasonally (P<0·05) in stock B and subgroup CUF. Infection was also associated (P<0·05) with host weight, and the highest prevalences and intensities were detected in 101–200 g and 201–300 g fish. Distribution pattern of E. scophthalmi in subgroups CUF and DUF had a variance higher than the mean, indicating overdispersion. The minimum period necessary for the first detection of the parasite and for the appearance of disease symptoms and mortality, varied depending on the stock and introduction date, although a long pre-patent period was always observed. Several factors, such as host density, parasite recruitment and parasite-induced fish mortality can contribute to the observed distribution pattern. Risk factors found to be associated with E. scophthalmi infection, including water quality and accumulation of infective stages in the culture tanks, should be considered when designing control strategies to prevent the introduction and spread of infective stages in the facilities.

In order to evaluate the damage of molten salt mixtures in waste incineration environments, the alloy 625 was exposed to a molten KCl-ZnCl2 mixture at 650 ºC for 200 hours. The corrosion process was monitored by electrochemical impedance spectroscopy (EIS). After exposure the corrosion products were analyzed by X-ray diffraction and SEM. Two different electrochemical impedance models were found to describe the electrochemical processes. In the early stages of corrosion the alloy developed a protective Cr2O3 scale which turned into a porous spinel oxide scale after 100 hours.

Using MacDowell-Mansouri theory, in this work we investigate a superfield description of the self-dual supergravity in the context ofAshtekar theory. We find that in order to reproduce previous results on supersymmetric Ashtekar formalism, it is necessary to properly combine the supersymmetric field strength in the Lagrangian. We extend our procedure to the case of supersymmetric Ashtekar formalism in eight dimensions.

ABSTRACTPulsed-field gel electrophoretic analysis of 2,144 methicillin-resistant Staphylococcus aureus(MRSA) strains isolated from patients in Spanish hospitals over a 7-year period revealed 17 predominant profiles. Typing showed the replacement of Iberian clone E1 (ST247-MRSA-I) by two prevalent clones, E7 and E8, that are closely related to each other and have the same genetic background as ST125-MRSA-IV.

We investigate the possibility of extending the Ashtekar theory to eight dimensions. Our approach relies on two notions: the octonionic structure and the MacDowell-Mansouri formalism generalized to a spacetime of signature 1 + 7. The key mathematical tool for our construction is the self-dual (antiself-dual) four-rank fully antisymmetric octonionic tensor. Our results may be of particular interest in connection with a possible formulation of M-theory via matroid theory.

Various experimental methods are currently employed for the determination of the trap parameters. Methods based on the glow curve shape extract information from a glow peak utilizing the temperature at the maximum emission, TM, the temperature on the ascending part of the peak ,T1, which corresponding to half peak intensity and the temperature on the descending part of the peak, T2, also corresponding to the half peak intensity; as well as, the half width parameters and the symmetry properties. In order to obtain the kinetic order b and the trap parameters, ZrO2 samples were exposed to 260 nm ultraviolet radiation (UVR). The trapping kinetics parameters of the ZrO2 dosimetric peak using the shape of the glow curve were then determined. The order of kinetics followed by the main peak was also determined using the same method. The values of activation energy E and frequency factor ,s, for the main peak of ZrO2 obtained by the above mentioned methods, showed a good agreement among them.

This paper presents the preparation method, luminescent characteristics and the results of studying the thermoluminescence (TL) properties of zirconium oxide (ZrO2) exposed to 260 nm ultraviolet radiation. The glow curve of ZrO2+PTFE pellets exhibited one peak centered at 180°C about 30°C lower than that the commercially available aluminum oxide peak (Al2O3:C). TL response as a function of spectral irradiance showed good linear in the range from 2.4 to 3000 µJ/cm2 of spectral irradiance. Experimental results of studying the thermoluminescent (TL) properties of ZrO2+PTFE exposed to ultraviolet radiation allow to propose zirconium oxide as an excellent candidate as ultraviolet radiation dosimeter.

We present an InAsSb interband photodetector grown by molecular beam epitaxy on GaSb substrate which operates in the mid-infrared domain (3–5 µm). To achieve uncooled high performance detection, the design of the structure was optimized to reduce the noise-inducing currents due to generation-recombination processes and diffusion currents. The technological procedure was further improved by using alkali sulfur passivation that suppresses surface leakage currents along the mesa edges. As a first result, the room temperature detectivity D* of the InAsSb photodiode, extracted from measurements, is comparable to the commercial HgCdTe device with a detectivity equals to 1 × 1010 cm Hz1/2 W–1 at about 3.5 µm. (© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Stabilization of tetrameric transthyretin (TTR) by binding of small ligands is a current strategy aimed at inhibiting amyloid fibrillogenesis in transthyretin-associated pathologies, such as senile systemic amyloidosis (SSA) and familial amyloidotic polyneuropathy (FAP). A kinetic assay is developed for rapid evaluation of compounds as potential in vitro inhibitors in a high-throughput screening format. It is based on monitoring the time-dependent increase of absorbance due to turbidity occurring by acid-induced protein aggregation. The method uses the highly amyloidogenic Y78F mutant of human transthyretin (heterogously expressed in Escherichia coli cells). Initial rates of protein aggregation at different inhibitor concentrations follow a monoexponential dose−response curve from which inhibition parameters are calculated. For the assay development, thyroid hormones and nonsteroidal antiinflamatory drugs were chosen among other reference compounds. Some of them are already known to be in vitro inhibitors of TTR amyloidogenesis. Analysis time is optimized to last 1.5 h, and the method is implemented in microtiter plates for screening of libraries of potential fibrillogenesis inhibitors.

Gossans are the products of intense oxidation of massive sulphide deposits exposed at the surface. In the Filón Sur deposit (Tharsis, Huelva), a detailed petrological and mineralogical study of the gossan has allowed us to establish the distribution and abundance of the main mineral phases in the gossan profile. Among these mineral phases, beudantite is present in the whole profile, although it tends to concentrate towards the lower part, where this mineral can reach up to 40%. Chemical analyses of beudantite have shown the presence of significant amounts of As and Pb in the structure. Since the content of As and Pb in the original sulphides is very low, beudantite acts as a sink for these two elements during the gossan formation process. This natural mechanism of As and Pb fixation can have important implications for remediation of areas affected by acid mine drainage.

ABSTRACTThe pharmacokinetics and toxicities of free sodium stibogluconate (SSG) and two vesicular formulations of this drug (a nonionic surfactant vesicular formulation of SSG [SSG-NIV] and SSG-NIV-dextran) were determined after treatment with a single intravenous dose in healthy dogs and were related to their antileishmanial efficacies in mice. Analysis of the curves of the concentrations in plasma after intravenous administration of SSG and SSG-NIV in dogs showed that both formulations produced similar antimony (Sb) pharmacokinetics. In contrast, treatment with SSG-NIV-dextran significantly modified the pharmacokinetics of the drug. The elimination half-life was four times longer (280 min) than that observed after administration of SSG (71 min) (P= 0.01), and the volume of distribution at steady state (VSS) was also increased (VSSfor SSG, 0.21 liters/kg; VSSfor SSG-NIV-dextran, 0.34 liters/kg [P= 0.02]), thus indicating that drug encapsulation favors the distribution of Sb into organs and increases its residence time in tissues. This would explain the superior antileishmanial efficacy of this formulation compared to those of the free drug in mice. No signs of toxicity were found in dogs after SSG and SSG-NIV administration. However, SSG-NIV-dextran treatment was associated with short-term toxicity, demonstrated by the development of chills and diarrhea, which cleared by 24 h postdosing, and hepatic dysfunction at 24 h postdosing (P< 0.05). The levels of all the biochemical parameters had returned to normal at 1 month postdosing. No signs of toxicity were observed in mice treated with all three formulations.

A new MoVTeO mixed oxide has been obtained during the calcination of the corresponding catalyst precursor mixture at 600 °C in N2. The crystal structure has been studied by means of X-ray diffraction, electron diffraction, high-resolution electron microscopy, and diffuse reflectance spectroscopy. Its XRD pattern, similar to those observed in hexagonal tungsten bronze (HTB) K0.13-0.33WO3, was indexed on the basis of a hexagonal cell of parameters a = 0.727 nm and c = 0.4012 nm. However, the electron microscopy study reveals the crystals as being formed by structural domains of an orthorhombically distorted unit cell derived from the HTB structure. Microstructural details are discussed in terms of tellurium location inside the hexagonal tunnels of the structure. The results obtained constitute the first step for elucidating the role of this new orthorhombic phase in the effectiveness of Mo−V−Te−Nb mixed oxide catalysts.

We analysed the effect of adding rosemary and tocopherol extracts, two natural antioxidants, on the colour stability of paprika stored at different temperatures and degrees of relative humidity. Any possible synergistic effect of their joint use was also investigated. The experimental data concerning colour loss, as determined by the ASTA 20.1 method, fitted first- and second-order kinetics, which provided the rate constants of colour loss and half-lives of the samples. The first finding concerned the antagonistic effect between storage temperature and humidity. The antioxidants had a clear protective effect on colour stability in all the conditions assayed, the superior effect of one or the other depending on the storage temperature. A synergistic effect of both antioxidants at temperatures between 25 and 40 °C was evident. The experimental data referring to colour loss for most of the storage conditions assayed fitted second-order kinetics best. © 2002 Society of Chemical Industry

Condensation of N-substituted glycines with chiral 3-allyl-2-formyl perhydro-1,3-benzoxazines forms an azomethine ylide that cyclizes to give octahydropyrrolo[3,4-b]pyrrole derivatives. The [3 + 2] dipolar cycloadditions are stereoespecific leading to a single diastereoisomer. The chemical yields are dependent on the reaction temperature and the presence or absence of a base.

The nature and redox properties of vanadium species on metal oxide supported vanadium catalysts have been studied. The calcined metal oxides&sbd;Al2O3, MgO, Mg−Al−hydrotalcite (Al/Mg = 0.33), and Mg−Al−Spinel (Al/Mg = 3.0)&sbd;have been employed as supports. TPR and IR spectra of adsorbed CO show a different reducibility of the vanadium species related to the acid−base character of the metal oxide support. This is also confirmed by the EPR results of both calcined and reduced catalysts. A reduction of V⁵⁺ to the V³⁺ species seems to be more favored on acid metal oxides. On basic metal oxide supports, the reducibility seems to be hindered, leading preferentially to the formation of V⁴⁺, although V³⁺ ions are also formed at higher reduction temperatures. A shift in the carbonyl frequency of the V⁴⁺−CO and V³⁺−CO complexes to lower frequencies by increasing the basicity of the support could be related to an electron donor effect of the support on the electron density of the vanadium species. In addition, a higher reoxidation ability of the V⁴⁺ and V³⁺ species is observed on the more acidic supports than on the basic ones.

The effect of molecular weight and long-chain branching on the crystallization analysis fractionation (CRYSTAF) of ethylene homopolymers was investigated. Several ethylene homopolymers were prepared with different molecular weights and levels of long-chain branching to isolate these effects from the dominant effect of comonomer content on crystallizability measured by CRYSTAF. Molecular weight effects might be significant for samples with number-average molecular weights below 5000, but this effect can be corrected if terminal methyl groups are taken into account. Long-chain branching has only a very small effect on the CRYSTAF profile of the samples investigated in this study. © 2001 John Wiley & Sons, Inc. J Polym Sci Part B: Polym Phys 39: 1616–1628, 2001

Since 1990 a clone of gentamicin and methicillin-resistant Staphylococcus aureus(MRSA) has remained endemic in our hospital, but since January 1996 a gentamicin-sensitive strain has progressively replaced the previous clone. We characterized the phenotypic and molecular pattern of the MRSA strains isolated in our hospital in 1996 and compared prospectively the epidemiological, clinical and evolutionary characteristics of ninety patients infected or colonized by gentamicin-sensitive MRSA (GS-MRSA) (49) and by gentamicin-resistant MRSA (GR-MRSA) (41). Finally we studied the variation of aminoglycoside consumption in our hospital from 1989 to 1996. We observed two antibiotypes (GS-MRSA and GR-MRSA) corresponding to two major chromosomal patterns. Patients with GS-MRSA usually acquired the infection 72 hours after hospital admission. No significant differences were observed in epidemiological characteristics, clinical presentation and evolution between patients with GS-MRSA and GR-MRSA. Since 1989 aminoglycoside intake in our hospital has decreased by 46%.

The Tinto and Odiel are small rivers draining one of the largest sulphide deposits in the world. As a result of these deposits and a large industrial complex, the adjacent marine area receives a high amount of metal input. Mercury distribution in the Tinto-Odiel estuary, the Huelva Ría and the Gulf of Cádiz was assessed in water and suspended particulatematter (SPM) and sediments. In the rivers and estuaries, dissolved (HgD)and particulate (HgP) mercury showed wide variations (13 to 200 pM and0.3 to 330 nmol g-1respectively) depending on the presence or notof sulphidic waters, phosphogypsum deposits, detrital pyrite and oxyhydroxides.In the Ría, concentrations were lower than 10 pM and 4.5 nmol g-1for HgD and HgP respectively. In surface waters of the Gulf of Cádiz, the average HgD concentration (pm standard deviation) was 2.9 pm 0.9 pM, which is similar to that of North Atlantic Central Waters. The surface sediments collected in the rivers, the Ría and the Gulf showed systematically enriched mercury compared to pre-industrial levels. Vertical mercury profiles in dated sediment cores were typical of anthropogenically influenced environments starting in the early Roman age. These distribution features suggest that most of the Hg discharged by the Huelva Ría is trapped in the sediments of the Gulf of Cádiz.