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Cutaneous squamous cell carcinoma (cSCC) is one of the most common types of malignant skin cancer in dogs, representing 3.9–10.4% of all canine skin tumours. Although the metastatic potential of cSCC is debated, it appears to mimic that observed in man. In man, predictive histopathological features for metastasis include tumour depth, lesions >5–6 mm in depth, and invasion of muscle, cartilage or bone. In dogs, some reports have focused on the clinical features and long-term progression of cSCC, but a gold standard treatment has not yet been developed. We explored the protein expression of kallikrein-related peptidase 5 (KLK5), an important modulator of skin homeostasis, in normal canine skin and in examples of cSCC. KLK5 was highly expressed in the upper stratum granulosum, stratum corneum, hair follicles and sweat glands, skin sites where human KLK5 has been shown to be involved in physiological processes including keratinocyte desquamation, antimicrobial defence, lipid permeability and pigmentation. In cSCC, tumour cells at the deep margin, as well as those in the centre of keratin pearls, displayed cytoplasmic expression of KLK5. Some of the KLK5 immunoreactive cells also expressed vimentin, suggesting that they may be undergoing epithelial–mesenchymal transition and therefore have a more invasive behaviour than those expressing only KLK5. KLK5 may be a novel molecular biomarker useful for predicting prognosis of cSSC in dogs. Image 1 [ABSTRACT FROM AUTHOR]

This is an empirical analysis of the dynamic behavior of Discrete-Time Recurrent Neural Networks (DTRNN) with two neurons based on the existing bifurcations on the full 4-dimensional synaptic weights space. We describe the existing bifurcation manifolds and the corresponding expected behavior in each region delimited by them in terms of the existing attractors. We found an unexpectedly rich variety of behaviors, however, finite and classifiable. We propose also an algebraic nomenclature that helps in the understanding of the underlying structure in the weights space. [ABSTRACT FROM AUTHOR]

Abstract: Different models are proposed in the literature to study the musculo-skeletal system. These models differ in several aspects like the number of segments in which the system is divided or the way to model articular joints. Marker residual analysis is a widely used method to evaluate how well the model fits the experimental measurements. However, the same model can yield different values of marker residuals depending on the PGA (Protocol of Gait Analysis) employed. The goal is to analyse the changes in the marker residuals obtained with different PGAs when a certain mechanical parameter is modified. Two of the most important parameters in the kinematic analysis have been studied: the length of a segment and the mechanical model of a joint. The results show that marker residuals obtained using some PGA do not provide valuable information to decide the best value of the analysed parameter. Values of the residuals computed using a PGA where the position of the markers is treated with the GOM (Global Optimization Method) are proposed to quantify the effect of certain parameters in the model. [Copyright &y& Elsevier]

Abstract: This work reports the effect of Co content and catalysts preparation on the surface structure of two catalyst series prepared by either co-impregnation or sequential impregnation and their catalytic activity for the simultaneous hydrodesulphurisation (HDS) and hydrodenitrogenation (HDN) of gas oil. Structural characteristics and degree of dispersion of the Co and Re phases in the oxidic catalyst precursors were obtained by X-ray diffraction, energy-dispersive X-ray analysis, UV–vis diffuse reflectance spectroscopy (DRS) and electrophoretic migration (EM), and in the sulphided catalysts by X-ray photoelectron spectroscopy (XPS). The UV–vis diffuse reflectance spectra demonstrated that Co in its oxidic state was in tetrahedral coordination (as surface CoAl2O4) and in octahedral coordination (as surface Co3O4), with a relative Co3O4/CoAl2O4 proportion increasing with Co content, and that Re was present mainly as distorted isolated ReO4 − monomeric species on the alumina surface and in small amounts probably as associated ReO4 − type Re2O7 in high Co-content catalysts. Consistently, XPS results of sulphided catalysts revealed that in both series the major part (>67%) of the Co remained in oxided state, while the Re phase was fully sulphided. The dispersion of sulphided Re decreased gradually with Co loading for the co-impregnated catalysts, due to the strong Co/alumina interaction, and drastically with Co incorporation for sequentially impregnation catalysts due to a partial dissolution and re-distribution of Re during Co impregnation. Catalytic activity results revealed synergetic effects in HDS and HDN between Co and Re in both series, with an optimum at an atomic ratio of about 0.40 Co/Re. The magnitude of the synergy was greater for HDS than for HDN, especially at low reaction temperature, and slightly higher for the coimpregnated catalysts reflecting the better Re dispersion. The observed CoRe synergy was thought to be related to the formation of a mixed Co-Re-S phase and to hydrogen spillover from separate Co sulphide to Re sulphide, participating to a different extent depending on the reaction temperature. [Copyright &y& Elsevier]

Abstract: Two series of NiRe catalysts supported on γ-Al2O3 and activated carbon having constant wt.% Re2O3 content (3.51 and 1.97, respectively) and various Ni/Re atomic ratios were prepared to investigate the promoting action of Ni on sulfided Re catalysts in the simultaneous hydrodesulfurization (HDS) and hydrodenitrogenation (HDN) of gas oil. The catalysts were characterized using textural analysis, X-ray diffraction, diffuse reflectance spectroscopy, energy-dispersive X-ray analysis and X-ray photoelectron spectroscopy. On both Ni(x)Re/Al2O3 and Ni(x)Re/C catalysts, the dependence of HDS and HDN activities showed initially an increase and subsequent decrease with increasing Ni content, with optimum Ni/Re atomic ratios of ∼0.94 for Ni(x)Re/Al2O3 catalysts and ∼1.25 for Ni(x)Re/C catalysts. The decline in activity was attributed to a reduction in Re dispersion and a low Ni sulfidation for the alumina-supported catalysts, and to a separate location of Re and Ni on the support surface, as well as to an incomplete Ni sulfidation for the carbon-supported catalysts. The synergetic effect in activity observed between Ni and Re was slightly higher for HDS than for HDN, especially at low reaction temperature (325°C) and on carbon-supported catalysts. On the basis of these promotional effects on catalytic activities and HDN/HDS selectivity, and the characterization results, the nature of the promotion observed on NiRe supported catalysts was discussed. [Copyright &y& Elsevier]

Abstract: The effects of Re content and catalyst preparation on the surface structure of two series of Re/γ-Al2O3 catalysts, prepared by one-step (Re(x)-I) and successive-step impregnation (Re(x)-II) methods, and their catalytic behaviour in the HDS and HDN of gas oil were studied. Characterization data by XRD, Raman spectroscopy and XPS revealed that the structure of Re on Re(x)-I and Re(x)-II catalysts in their oxidic state was very similar; Re in oxided state was present as two slightly different isolated ReO4- monomeric species coordinated to the alumina surface in all the range of Re content studied, but the Re coverage was slightly lower on Re(x)-I than on Re(x)-II catalysts. Upon sulfidation, the dispersion of Re decreased significantly and left to be monomolecularly dispersed above 0.5Reat.nm-2, especially for the Re(x)-I catalysts, causing therefore that the HDS and HDN activities of the two catalyst series reached maximum values at a Re content of about 0.5at.nm-2 and then decreased. The higher activity for both HDS and HDN reactions observed for the Re(x)-II catalysts are consistent with their higher dispersion of the Re sulfided phase. Both Re(x)-I and Re(x)-II catalysts showed exceptionally high HDN/HDS selectivity values, which were slightly higher for the Re(x)-II catalysts due to their slightly higher concentration of acid sites in the oxidic state. [Copyright &y& Elsevier]

Highlights: [•] We incorporated biosurfactant to the immobilized cell systems in BDS reactions. [•] We observed two mechanisms of immobilized cell systems action. [•] Tween 80 increased mobility of particles by reducing the interfacial tension. [•] BS increased solubilization of the sulfured substrates by formation of micelles. [•] BS represents a nontoxic compound that facilities degradations of sulfur molecules of gas oil. [Copyright &y& Elsevier]

Abstract: A new irradiation facility has been developed in the RA-3 reactor in order to perform trials for the treatment of liver metastases using boron neutron capture therapy (BNCT). RA-3 is a production research reactor that works continuously five days a week. It had a thermal column with a small cross section access tunnel that was not accessible during operation. The objective of the work was to perform the necessary modifications to obtain a facility for irradiating a portion of the human liver. This irradiation facility must be operated without disrupting the normal reactor schedule and requires a highly thermalized neutron spectrum, a thermal flux of around 1010 ncm−2 s−1 that is as isotropic and uniform as possible, as well as on-line instrumentation. The main modifications consist of enlarging the access tunnel inside the thermal column to the suitable dimensions, reducing the gamma dose rate at the irradiation position, and constructing properly shielded entrance gates enabled by logical control to safely irradiate and withdraw samples with the reactor at full power. Activation foils and a neutron shielded graphite ionization chamber were used for a preliminary in-air characterization of the irradiation site. The constructed facility is very practical and easy to use. Operational authorization was obtained from radioprotection personnel after confirming radiation levels did not significantly increase after the modification. A highly thermalized and homogenous irradiation field was obtained. Measurements in the empty cavity showed a thermal flux near 1010 ncm−2 s−1, a cadmium ratio of 4100 for gold foils and a gamma dose rate of approximately 5Gyh−1. [Copyright &y& Elsevier]

Abstract: The immobilization of Pseudomonas stutzeri using adsorption on different inorganic supports was studied in relation to the number of adsorbed cells, metabolic activity and biodesulfurization (BDS). The electrophoretic migration (EM) measurements and Tetrazolioum (TTC) method were used to evaluate adsorption and metabolic activity. Results indicate that maximal immobilization was obtained with an initial load of 14×108 cellsmL−1 for Al and Sep, whereas Ti requires 20×108 cellsmL−1. The highest interaction was observed in the P. stutzeri/Si and P. stutzeri/Sep biocatalysts. The IEP values and metabolic activities indicate that P. stutzeri change the surface of supports and maintains metabolic activity. A direct relation between BDS activity and the adsorption capacity of the bacterial cells was observed at the adsorption/desorption equilibrium level. The biomodification of inorganic supports by the adsorption process increases the bioavailability of sulphur substrates for bacterial cells, improving BDS activity. [Copyright &y& Elsevier]

Abstract: Biocontrol capacity of two plant growth-promoting rhizobacteria (PGPR) strains, against blast disease in rice paddy fields in Southern Spain was studied in three cropping seasons. Both strains (Pseudomonas fluorescens Aur 6 and Chryseobacterium balustinum Aur 9) had already shown biocontrol capacity against pathogens, ability to induce systemic resistance against leaf pathogens and against salt stress in different plant species. Bacterial treatments were carried out on seeds and/or on leaves. Strains were inoculated individually and in combination. Protection against natural disease incidence was evaluated, and rice production and quality measured in 2005 and 2006 trials. In 2004, natural disease incidence was low (between 0.1% and 0.35% of damaged leaf surface) due to environmental conditions; under these conditions, both strains significantly protected plants against rice blast. In 2005, disease incidence was higher than in 2004, reaching higher values of affected leaf surface in controls. In these conditions, each strain individually protected rice against rice blast, although the combination of both strains was the most effective treatment. All three treatments (Aur 6, Aur 9 and Aur 6+Aur 9) reached 50% protection in panicles, with Aur 9 being the most effective. In 2006, the most effective treatment was the combination of both strains on leaves in three physiological stages, suggesting a biocontrol mediated protection. On the other hand, when bacteria were applied to seeds, disease incidence decreased up to 50%, suggesting induction of systemic resistance. Finally, a direct relation between protection mediated by the PGPR and the increase in rice productivity (mT/ha) and quality (weight of 1000 seeds and number of intact grains after milling) was found. [Copyright &y& Elsevier]

Abstract: The promotion effect of Mn, Fe, Co, Ni, Cu and Zn sulfides on the hydrodesulfurization (HDS) activity of Mo and W sulfides, under experimental conditions like industrial ones, using staked beds, was studied. Synergism between staked beds in all the studied pairs, with a magnitude that leads a volcano curve with a maximum in Co and Ni sulfides was detected. Promotion was well explained by the formation of spillover hydrogen (Hso) in the first bed (in which Mn, Fe, Co, Ni, Cu or Zn sulfides supported on γ-Al2O3 were located) that migrate to the second bed (in which Mo or W sulfides supported on γ-Al2O3 were located), 5mm below. [Copyright &y& Elsevier]

Synergetic effects in hydrodesulfurization (HDS) have been investigated in operating conditions different from all those mentioned in literature yet. A synergism is observed between Co(x)/γ-Al2O3 or Ni(x)/γ-Al2O3, and Mo(y)/γ-Al2O3 beds separated by a 5mm of γ-Al2O3 or SiO2 bed. The results were obtained in conditions very close to those of industrial processes, namely using a high-pressure continuous-flow-reactor and gas-oil as feed, in contrast to model feeds used in most similar experiments. Compared to the activity of the individual beds, a significant increase of HDS activity is observed at 325, 350 and 375°C, in the case of Co and Ni. As the Co (Ni) containing beds are physically separated from each other, no mutual contamination susceptible to lead to the formation of Co–Mo–S or Ni–Mo–S is possible. Several other alternative explanations have been examined, but it seems that the logical conclusion is that spillover of hydrogen could explain the phenomenon. No synergetic effect was detected using SiC as separator. The effects of changes in the cobalt or nickel (x), and molybdenum (y) contents and of the reaction temperature over the synergetic effect are also described and discussed. The effect of a diffusion of spillover species (probably hydrogen Hso) over a 5mm distance is so conspicuous that it seems difficult to rule out an important flow of Hso and thus a much stronger effect in real CoMo and NiMo catalysts where the sulfided elements are at nanometer distances from each other. This makes even reasonable the hypothesis that hydrogen spillover could actually play an essential role in the HDS reaction over molybdenum-containing catalysts. [Copyright &y& Elsevier]