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The influence of both topography and optical constants on the optical reflection of bright-annealed AISI 430 ferritic stainless steel has been analyzed to correlate these characteristics with the occurrence of the unwanted haze effect in industrial products. This work reports the analysis of the total-integrated-scattering spectra of bright-annealed AISI 430 ferritic steel plates, on the basis of the microfacet model for the bidirectional reflectance function developed by He and Torrance [Siggraph ’91, Proc. of the 18th Annual Conference on Computer Graphics and Interactive Techniques, (1991), p. 175]. Such an approach allows for modeling the optical reflection of these stainless-steel industrial products based on roughness parameters, root-mean square height, and autocorrelation length, derived from scale-limited topographic maps. The functional choice of the cutoff wavelength in the high-pass Gaussian filtering of the topographic map is proven critical. Additionally, optical constants n and k of the steels are estimated based on their total reflection spectra, measured in an 8°/di optical geometry. The results suggest that the haze effect could be due to a non-controlled increase in the thickness of the passive layer during the bright-annealing process.

This paper presents a prominent e-learning tool that is part of deliverable packages of Hy2Green Project (Ref. 2017-1-ES01-KA203-038302). The aim of the project is to develop an online training course that can help to improve new professional profiles in hydrogen technologies, in line with the energy transition model in Europe. As part of this training course and as result of a team collaboration, a remote laboratory based on hydrogen technology has been designed and implemented. Through the online platform, students from every part of the world can access remotely and in real-time, to a real laboratory built from a scaled green-hydrogen production plant. The green-hydrogen production plant has, in addition to hydrogen production and storage subsystems, a fuel cell, through which electricity is generated with the stored hydrogen. The developed remote laboratory offers technological and educational improvements. From the technological point of view, it allows handling a real installation, throughout the entire energy conversion process, being able to carry out laboratory tests, to characterize the different components. This remote laboratory is proposed as a multidisciplinary tool, where students develop their skills in automatic control, system modelling and renewable energy management. On the other side, from the educational point of view, this proposal contributes to democratization of education. That is nowadays equipment related to hydrogen technology is not cheap, so this implies that not all educational centres cannot afford to have a hydrogen laboratory. The remote laboratory presented in this work offers the possibility to carry out laboratory practices to whatever the student and the university are.

La atención al ictus en urgencias se inicia antes de la llegada del paciente. La activación de código ictus y el preaviso al equipo de ictus debe ser parte de la rutina clínica. El tiempo es un aspecto esencial para conseguir beneficio clínico y, en una primera fase, este debe ser el planteamiento que ha de regir el manejo diagnóstico del ictus a su llegada al servicio de urgencias. El diagnóstico clínico, sindrómico y etiopatogénico irán en paralelo a la realización de las pruebas diagnósticas instrumentales necesarias para conseguir, en el menor tiempo posible, un conocimiento de la situación del paciente, enfocado a la aplicación del tratamiento más adecuado para cada paciente concreto. Un registro adecuado de tiempos y resultados guiará la implementación de medidas en el manejo del paciente con ictus.

Today, companies need to assess the recoverability of their products from the design phase, not only for legislative reasons but also to appraise how they will be able to recover all or part of their value when they reach end of life. The main reference calculation methods are both the norm ISO 22628, which addresses the automotive industry, and the IEC/TR 62635 report, which addresses the electrical and electronic equipment industry. Both reference methods only focus on mass preservation indicators (as legislation requires) but ignore important aspects such as material quality loss, environmental impacts, and economic value preservation. Indeed, multi-criteria assessment is needed as it can be a key factor for both improving product design and to help designers integrate recycled materials into their products. In that regard, several other studies exploring multi-criteria analysis (i.e.technical, economic and/or environmental-based) do exist. The aim of this paper is to (i) present a critical review of current recoverability assessment methods and (ii) find the existing gaps by comparing whether the used indicators meet the designer needs or not.

Confirmation of tuberculosis (TB) in children is difficult, so clinicians use different procedures when deciding to treat.

La obesidad infantil constituye uno de los principales problemas de salud de nuestro país, por su alta prevalencia y por el gran número de comorbilidades asociadas. Las cifras de presión arterial (PA) alta constituyen un factor de riesgo para enfermedad cardiovascular que se presenta de manera temprana en niños obesos, por lo cual es importante su diagnóstico desde edades tempranas.

Turbulent mixing layers associated with streamwise uniform and nonuniform flows in compound channels (main channel with adjacent floodplains) are experimentally investigated. The experiments start with uniform flow conditions. The streamwise nonuniformity is then generated by imposing an imbalance in the upstream discharge distribution between main channel (MC) and floodplains (FPs), keeping the total discharge constant, which results in a transverse depth‐averaged mean flow. This study first aims at assessing the effect of a transverse flow on the mixing layer and coherent structures that form at the MC/FP interfaces. A wide range of initial velocity ratio or dimensionless shear between MC and FP is tested. The study second aims at assessing the effect of this velocity ratio on the mixing layer, for a fixed vertical confinement of flow. The total discharge was then varied to quantify the confinement effect. The results show that, far from the inlet section, Reynolds‐stresses increase with local velocity ratio for a fixed confinement and decrease with confinement for a fixed velocity ratio. It is also shown that, irrespective of confinement, the existence of quasi‐two‐dimensional coherent structures is driven by velocity ratio and the direction and magnitude of transverse flow. These structures cannot develop if velocity ratio is lower than 0.3 and if a strong transverse flow toward the MC occurs. In the latter case, the transverse flow is the predominant contribution to momentum exchange (compared with turbulent mixing and secondary currents), convex mean velocity profiles are observed, preventing the formation of quasi‐two‐dimensional structures. Owing to the numerous sources of longitudinal nonuniformity along overflowing rivers (e.g., the change in floodplain land occupation), the understanding of overbank nonuniform flows in a compound open‐channel (main channel and lateral floodplains) is of primary importance. Streamwise flow nonuniformity is characterized by a transverse flow across the river. At the interface between main channel (MC) and floodplain (FP), a mixing layer populated by turbulent vortices develops. When the flow is nonuniform, the mixing layer is strongly altered. These “nonuniform mixing layers” are encountered in several practical problems like mixing processes in rivers—e.g., sediments, nutrients, or pollutants transport from the MC to the FP—river restoration works, flood risk assessment studies. This paper presents an experimental investigation of nonuniform flows in compound channels, focusing on the mixing layer and the turbulent vortices. We assess the effects of the transverse flow on the turbulent vortices, as well as the effects of the MC/FP velocity ratio and of the vertical confinement of flow. The existence of quasi‐two‐dimensional vortices was found to be independent of the vertical confinement of flow (unlike uniform flows) but strongly driven by the velocity ratio and the direction and magnitude of the transverse flow. Shear layer turbulence increases with local velocity ratio and with a decreasing vertical confinement of flowThe existence of quasi‐two‐dimensional coherent structures is driven by velocity ratio and the direction and magnitude of transverse flowCoherent structures cannot develop if velocity ratio is lower than 0.3 and if a significant transverse flow toward the main channel occurs

Heavy boron‐doping layer in diamond can be responsible for the generation of extended defects during the growth processes (Blank et al., Diam. Relat. Mater. 17, 1840 (2008) []). As claimed recently (Alegre et al., Appl. Phys. Lett. 105, 173103 (2014) []), boron pair interactions rather than strain‐related misfit seems to be responsible for such dislocation generation. In the present work, electron microscopy observations are used to study the defects induced by heavy boron doping in different growth plane orientations. Facets of pyramidal Hillocks (PHs) and pits provide access to non‐conventional growth orientations where boron atoms incorporation is different during growth. TEM analysis on FIB prepared lamellas confirm that also for those growth orientations, the generation of dislocations occurs within the heavily boron‐doped diamond layers. Stacking faults (SFs) have been also observed by high resolution transmission electron microscopy (HREM). From the invisibility criteria, using weak beam (WB) observation, 1/2[11¯0]and 1/6[112¯], Burgers vectors have been identified. Their generation behavior confirms the mechanism reported by Alegre et al. where local in‐plane strain effects induced at the growing surface of the diamond lattice by the neighboring of several boron atoms cause the generation of such extended defects.

Valorar la relación entre la aparición de dolor en punta de vástago tibial con una disminución de la resistencia ósea preoperatoria mediante microindentación ósea. En segundo lugar, conocer la utilidad potencial de la algometría de presión en el diagnóstico y seguimiento de este grupo de pacientes.

Several letters to the editor are presented in response to articles in previous issues including "Do GM Trucks Even Matter Now?" in the February 2014 issue and another about towing equipment and terminology.

In this paper, verification and validation of a turbulence closure model is performed for an experimental compound channel flow, where the velocity and turbulent fields were measured by a Laser Doppler Velocimeter (LDV). Detailed Explicit Algebraic Reynolds Stress Model (EARSM) simulations are reported. There are numerous methods and techniques available to evaluate the numerical uncertainty associated with grid resolution. The authors have adopted the Grid Convergence Index (GCI) approach. The velocity components, the turbulence kinetic energy (TKE), the dissipation rate and the Reynolds stresses were used as variables of interest. The GCI results present low values for the u velocity component, but higher values in what concerns the v velocity component and w velocity component (representing secondary flows) and for Reynolds stresses RSxy and RSyz. This indicates that the mean flow has converged but the turbulent field and secondary flows still depend on grid resolution. Based on GCI values distribution, the medium and fine meshes were further refined. In addition to GCI analysis, the authors have performed linear regression analysis for estimating the mesh quality in what concerns small value variables. Comparison of numerical and experimental results shows good agreement. [ABSTRACT FROM AUTHOR]

The influence of surfactant structure on the formation of lamellar liquid crystals with very low surfactant concentration was investigated for systems composed of oleic acid, diethyleneglycol ethyl ether and water. Surfactants belonging to anionic and cationic families were checked: phosphated oleyl ether 3 EO (PO3EO), triethanolamine oleate (TEAO) and sodium lauryl ether sulphate (SLES) as anionic surfactants and two alkyl trimethylammonium bromide type (C12TAB and C14TAB) as cationic surfactants. For each of the surfactants, the appropriate relationships between surfactant, oleic acid and glycol to furnish lamellar liquid crystals when these basic compositions were further diluted with water were established. The appropriate ranges of dilution allowing the liquid crystal formation were also determined. These liquid crystals presented an attractive appearance because of their transparency and high viscosity, although in the beginning of its formation, a short range of less viscous compositions (so called liquid/gel compositions) appears in some cases. Through water dilution, the initial surfactant percentages are noticeably reduced being possible liquid crystals with 2–5 wt% of surfactant.

Binding between a component of the crude hot water extract obtained from Allium sativum crushed bulbs (ASw) and cholera toxin B pentamer (CTB) was detected by STD NMR experiments. Bioassay-oriented fractionation allowed the partial identification of a high molecular weight polysaccharide mainly composed of galactose as the bioactive complex against CTB. This work represents the first example of screening of a medicinal plant by NMR against a specific disease, and corroborates traditional medical uses of the species. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)

The complex trans-[Rh(CF3)(CNXy)2(PPh3)] (1) reacts with SO2, tetracyanoethylene (TCNE), or maleic anhydride (MA) to give the complexes [Rh(CF3)(CNXy)2(PPh3)L] (L = SO2 (2), TCNE (3), MA (4)) and with CO or CF3CO2H to give, respectively, mixtures containing mainly [Rh(CF3)(CNXy)2(CO)(PPh3)] or trans-[Rh(CNXy)2(PPh3)2]CF3CO2, which is prepared in better yield by reaction of trans-[RhCl(PPh3)2(CO)] with XyNC and NaCF3CO2. [Rh(CF3)(CNXy)3] (6) is prepared by reaction of [Rh(CF3)(CNXy)3(PPh3)] (7) with 35% H2O2 or, better, by reaction of [Rh(μ-OH)(COD)]2 with XyNC and Me3SiCF3. The reaction of 6 with tetracyanoethylene (TCNE) or maleic anhydride (MA) gives the complexes [Rh(CF3)(CNXy)3L] (L = TCNE (8), MA (9)). The oxidative addition reaction of MeI or n-C4F9I with complex 6 gives the octahedral Rh(III) complexes [Rh(CF3)(R)I(CNXy)3] (R = Me (10), n-C4F9 (11)). In an attempt to obtain single crystals of complex 11, a few crystals of [{Rh(CF3)(n-C4F9)(CNXy)2}2(μ-I)2] (12) were obtained. The crystal structures of complexes 2−4 and 12 have been determined by X-ray diffraction studies.

This work contributes to an improved understanding of the structure and dynamics of ester-containing solvents. A broad experimental study has been performed on the thermophysical properties of (C6−C14) n-alkane + (C1−C4) alkylbenzoate binary solvents over the whole composition range and within the 278.15−318.15 K temperature range. The excess and mixing derived properties were analyzed in terms of structural effects and intermolecular forces. To put forward reliable models that may describe the behavior of these complex mixtures, the cubic equations of state by Soave and Peng−Robinson were combined with a set of 10 different mixing rules to correlate the volumetric and viscometric properties. Likewise, to gain a deeper insight into the structure of these solvents the Prigogine−Flory−Patterson and extended real associated solution models were applied to correlate the excess molar volumes. The different contributions to the excess and mixing properties were analyzed as well as their variation with the nature and size of the components involved.

Abstract: The preparation of biocompatible microemulsions of soybean oil in systems made of anionic surfactant, oleic acid, water, and several glycols was considered. The selected glycols were ether derivatives (methyl, ethyl, dimethyl, and diethyl ether) of ethylene glycol and diethylene glycol. The study was performed using pseudoternary phase diagrams in which the three apexes were occupied by soybean oil, a combination of surfactant/oleic acid, and a combination of water/glycol, respectively. The widest regions of microemulsions were obtained for systems containing methyl ether and especially ethyl ether of both ethylene glycol and diethylene glycol. The two latter compounds allowed the preparation of oil-in-water, bicontinuous, and water-in-oil microemulsions with final surfactant contents of 3–4%.

Abstract Lamellar liquid crystal formulation, with very low surfactant content, was optimized for the system made of phosphated oleyl ether 3 mol ethylene oxide as anionic surfactant, oleic acid as hydrophobic ingredient, diethyleneglycol monoethyl ether as cosolvent and water. The appropriate relationships between surfactant, fatty acid and glycol to promote the lamellar liquid crystal structure through further water dilution, were established. The physical appearance of these liquid crystals corresponded to viscous transparent gels. The realms of existence of the gels were stated in terms of minimum–maximum percentage of water incorporated. The main goal of this research was to decrease the surfactant content (in the range of 2–5%) needed to form liquid crystals, when usually high percentages are necessary. The study was completed with the rheological behaviour and structural parameters of some of these transparent gels. The attractive aspect of the samples, the perfect transparency and compactness, as well as the similarity to the lamellar liquid crystal structure of the intercellular lipids in the stratum corneum, permit consideration of such gels as adequate topical formulations both in cosmetics and pharmaceuticals.

The heptapeptide 1, NAc-Gly-Val-DIle-Thr-Arg-Ile-ArgNHEt, a structurally modified fragment derived from the second type-1 repeat of thrombospondin-1 (TSP-1), is known to possess antiangiogenic activity. However, therapeutic utility could not be demonstrated because this peptide has a very short half-life in rodents. To optimize the PD/PK profile of 1, we initiated a systematic SAR study. The initial structural modifications were performed at positions 5 and 7 of peptide 1 and at the N- and C-termini. Out of several hundred peptides synthesized, the nonapeptide 5 (ABT-526) emerged as a promising lead. ABT-526 inhibited VEGF-induced HMVEC cell migration and tube formation in the nanomolar range and increased apoptosis of HUAEC cells. ABT-526 showed acceptable PK in rodents, dog, and monkey. ABT-526, when incorporated in an angiogenic pellet implanted in the rat cornea at 10 μM, reduced neovascularization by 92%. Substitution of DalloIle in place of DIle in ABT-526 provided nonapeptide 6 (ABT-510), which was 30-fold less active than ABT-526 in the EC migration but 20-fold more active in the tube formation assay. In comparison to ABT-526, ABT-510 has increased water solubility and slower clearance in dog and monkey. Radiolabeled ABT-510 demonstrated saturable binding to HMVEC cells at 0.02−20 nM concentrations and was displaceable by TSP-1. ABT-510 and ABT-526 were shown to significantly increase apoptosis of HUAEC cells. ABT-510 was effective in blocking neovascularization in the mouse Matrigel plug model and inhibited tumor growth in the mouse Lewis lung carcinoma model. Previous studies had shown that ABT-510 was effective in inhibiting the outgrowth of murine melanoma metastases in syngeneic mice and in blocking the growth of human bladder carcinoma implanted in nude mice. It had been also shown that ABT-510 could regress tumor lesions in pet dogs or cause unexpected stabilization of the disease in advanced canine cancer. ABT-526 and ABT-510 are the first compounds in the class of potent inhibitors of angiogenesis that mimic the antiangiogenic function of TSP-1. ABT-510 is currently in phase II clinical studies.

Abstract: The influence of glycol structures on the formation of lamellar liquid crystals with the physical appearance of transparent gels in formulations composed of an anionic surfactant, oleic acid, and water was investigated. The glycols studied belong to alkyl derivatives of ethylene glycol and diethylene glycol. The relationships between the ingredients of the so-called basic compositions—surfactant, oleic acid, and glycol—were optimized to form transparent gels when diluted with water. The ranges in which transparent gels existed were compared for the systems with different glycols. The most suitable glycols, as defined by the lowest surfactant content in the final transparent gels, were ethylene glycol methyl ether and especially methyl and ethyl derivatives of diethylene glycol. Formulations with 2–3% surfactant could be prepared with these glycols. These data were correlated with the polarity of the glycol structures described by means of log P (octanol/water partition coefficient). Transparent gel formation occurred for log P values ranging from approximately 0.5 to −0.5, whereas liquid crystal formation did not result from higher or lower values.

Association of quaternary ammonium based surfactants with activated sludge from wastewater treatment plants has been studied. Adsorption isotherms on activated sludge particles and surface properties of a series of alkyl trimethyl ammonium compounds have been investigated. The effect of alkyl chain length and the water hardness in those physical-chemical properties have been evaluated. Adsorption on sludge increased with increasing the alkyl chain length in the cationic surfactant molecule. Linear relationships between critical micelle concentration (-log CMC) and efficiency of adsorption at the liquid/gas interface (pC20), and the number of carbon atoms in the alkyl chain length were found for the alkyl trimethyl ammonium compounds. Water hardness decreased the CMC values of the tested alkyl trimethyl ammonium homologues and the extent of their sorption to activated sludge. Langmuir and Freundlich adsorption isotherms described satisfactorily the equilibrium adsorption of the cationic surfactants on activated sludge.

The rhodium(I) fluoro complexes [RhF(COD)(PR3)] (R = Ph (1a), C6H4OMe-4 (1b), i-Pr (1d), Cy (1e); COD = 1,5-cyclooctadiene) react with Me3SiRF to afford the rhodium(I) perfluoroalkyl complexes [Rh(RF)(COD)(PR3)] (RF = CF3, R = Ph (2a), C6H4OMe-4 (2b), i-Pr (2d), Cy (2e); RF = n-C3F7, R = Ph (2c)), of which 2a,c were isolated as pure solids. [Rh(CF3)(NBD)(PPh3)] (3) was prepared by reaction of 2a with norbornadiene. The reactions of 2a−c with 2,6-dimethylphenyl isocyanide (XyNC) or t-BuNC, in a 1:2 molar ratio, gave the compounds trans-[Rh(RF)(CNR‘)2(PR3)] (RF = CF3, R‘ = Xy, R = Ph (4a), C6H4OMe-4 (4b); RF = CF3, R‘ = t-Bu, R = Ph (4a‘); RF = n-C3F7, R‘ = Xy, R = Ph (4c)). The reactions of 2a−c with an equimolar amount of XyNC gave mixtures containing complexes 4a−c as the major products. The peroxo complexes [Rh(CF3)(η²-O2)(CNXy)2(PR3)], (R = Ph (7a), C6H4OMe-4 (7b)) were isolated by reacting O2 with 4a,b, respectively. The complexes [Rh(RF)(CNR‘)3(PR3)] (RF = CF3, R‘ = Xy, R = Ph (8a), C6H4OMe-4 (8b); RF = n-C3F7, R‘ = Xy, R = Ph (8c)) were obtained by reaction of 2a−c with 3 equiv of XyNC. Formation of [Rh(CF3)(PPh3)(CO)3] (9) in the reaction of complex 2a with CO was spectroscopically observed. The crystal structures of complexes 4a, 7a, and 8a have been determined by single-crystal X-ray diffraction studies. The dynamic behavior in solution of the prepared complexes was studied by variable-temperature NMR.

An experimental setup for the measurement of densities for the compressed liquid phase of the N-methylpyrrolidinone/water binary solvent from 278.15 to 358.15 K over the full composition range and for pressures up to 60 MPa is reported. Experimental measurements were performed with a recently developed high-pressure vibrating-tube densitometer; the calibration procedure of the apparatus and the reliability and accuracy of the data provided were checked against literature values. The correlation of the density data with pressure and temperature was performed at each composition using the TRIDEN 10-parameter equation. From the experimental data, several derived properties were calculated and analyzed in terms of structural effects and intermolecular interactions. Likewise, the abilities of several cubic equations of state combined with several mixing rules to correlate the measured PVTx data were tested.

Abstract: The necessary conditions were established by which several biocompatible ingredients (phosphated oleyl ether 3 mol ethylene oxide as surfactant, oleic acid as the lipophilic ingredient, and diethylene glycol monoethyl ether and 1,2-propanediol as glycols) were combined to formulate transparent gels through dilution with water. This study was carried out at three constant levels of surfactant concentration (5, 10, and 15%), which determined in each case the appropriate ratios between the other three components to give transparent gels. These ratios were expressed as the global ratios between oleic acid and the two glycols together (ranging from 1∶9to 1∶3), whereas the internal ratios between the glycols moved in each case from 1∶0 to 0∶1. The systems with 5% of initial surfactant and a global ratio between oleic acid and the glycols of 1∶7 appeared to be the most effective for minimizing the final surfactant content. They furnished transparent gels at specified levels of water dilution, resulting in final surfactant concentrations in the range of 2–4%. Microscopic observation of the gels through polarized light showed the typical pattern of a lamellar liquid crystal structure. The mild characteristics of these gels, given their low surfactant content and the harmlessness of the other components, in addition to their attractive transparency and the rheological characteristics of plastic fluids make them suitable for application as topical formulations in the cosmetic or pharmaceutical fields.

Densities and dynamic viscosities of the N-methylpyrrolidone/(C1−C10) alkan-1-ols mixed solvents were measured at atmospheric pressure and 293.15, 303.15, 313.15, and 323.15 K over the whole composition range. The excess and mixing properties deduced from these data were interpreted in terms of intermolecular interactions and structural effects. The Soave−Redlich−Kwong and Peng−Robinson cubic equations of state and the modified extended real associated solution (ERAS) and the Prigogine−Flory−Patterson (PFP) models were used to correlate the excess molar volumes. Several correlation viscosity models were also used in data reduction.

As part of a study on the interactions between aromatic esters and n-alkanes, density, viscosity, and refractive index data were measured for methylbenzoate−n-alkane mixed solvents. From these data, excess molar volumes (%@mt;sys@%%@ital@%V%@rsf@%%@kn;1.5q@% %@sx@%m%@be@%E%@sxx@%%@mx@% ), mixing viscosities (Δmixη), excess Gibbs energies of activation of viscous flow (Δ%@mt;sys@%%@ital@%G%@rsf@%%@sx@%m%@be@%*E%@sxx@%%@mx@% ), and mixing refractive indices (ΔmixnD) were deduced. From the excess volumes, the partial molar volumes of the two components were deduced using the intercept method. The cubic equations of state (EOS) proposed by Soave−Redlich−Kwong and Peng−Robinson combined with two simple mixing rules were used to process the excess molar volumes. The change with temperature of the density and viscosity measurements enabled the activation enthalpy (Δ%@mt;sys@%%@ital@%H%@rsf@%%@sx@%m%@be@%&thermod;%@sxx@%%@mx@% ), activation entropy (Δ%@mt;sys@%%@ital@%S%@rsf@%%@sx@%m%@be@%&thermod;%@sxx@%%@mx@% ), Gibbs free energy (Δ%@mt;sys@%%@ital@%G%@rsf@%%@sx@%m%@be@%&thermod;%@sxx@%%@mx@% ), and thermal expansion coefficients (α) to be determined. These results were interpreted in terms of intermolecular interactions and structural effects. The ability of different one-parameter and two-parameter empirical models to predict mixing viscosities was also tested.

A perfectly mixed batch reactor was used for the determination of the intraparticle diffusivities of Na⁺ and K⁺ on commercial Amberlite IR-120 resin in different solvents:  water and solvents composed of different percentages of water and methanol, water and ethanol, and water and 2-propanol. A theoretical model was developed to describe the response of the system that includes the resistance to mass transfer inside the particle and the effect of the electric field (Nernst−Planck approximation). Equilibria were described using a homogeneous model based on the mass action law in which nonideal behavior for both the solution and the solid phase was taken into account. Simulations were performed to analyze the effect of the model parameters on the response curves. The values of intraparticle diffusivities of Na⁺ and K⁺ were obtained by nonlinear regression. Both the regression and the parameters were highly meaningful from the statistical point of view. A simple dimensionless relationship that relates diffusivity (through the Schmidt number) to different physical properties of solvents (namely, viscosity, dipolar moment, and density) and resin swelling was found.

Umbilical cord and venous blood samples were collected at the time of delivery from 52 mothers living in urban and rural areas of the Atoya River basin, Nicaragua. In a subsample of 24 mothers that delivered by Cesarean section, abdominal adipose tissue samples were also collected, as was breast milk later in lactation. Cord and venous blood sera were analyzed for 13 organochlorine pesticides: 1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane (pp′-DDT); 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (pp′-DDE); pp′-dichlorophenyldichlorodiene (pp′-DDD); α-hexachlorocyclohexane (α-HCH); β-hexachlorocyclohexane (β-HCH); γ-hexachlorocyclohexane (γ-HCH); δ-hexachlorocyclohexane (δ-HCH); toxaphene; dieldrin; endrin; aldrin; heptachlor; and heptachlor epoxide. In venous blood only pp′-DDE (100% of samples), pp′-DDT (1.92%), dieldrin (15.38%), heptachlor (15.38%), γ-HCH (7.69%), β-HCH (11.53%), and δ-HCH (1.92%) were found, whereas in cord blood only pp′-DDE (100%), pp′-DDT (3.84%), dieldrin (19.23%), and heptachlor (9.16%), were found. The persistent DDT metabolite pp′-DDE, present in all samples of blood serum, adipose tissue, and breast milk, was studied in relation to maternal characteristics such as body mass index (BMI), age, lactation experience, and fetal pesticide acquisition. Mean venous (7.12 μg/g) and cord (6.39 μg/g) pp′-DDE concentrations were not significantly different but were significantly correlated. pp′-DDE in maternal adipose tissue was positively correlated with pp′-DDE in cord blood (P=0.0001) and breast milk (P<0.0001) and marginally correlated with changes in BMI (r=−0.03088; P=0.06). There was a higher proportion of samples (58%) with a greater concentration of DDE in venous than in cord blood. Although DDE accumulation may be less during fetal development than during breast v201nfeeding, exposure during embryogenesis may be more important than during the postnatal period.

The p53 tumor suppressor protein, a key regulator of cellular responses to genotoxic stress, is stabilized and activated after DNA damage. The rapid activation of p53 by ionizing radiation and radiomimetic agents is largely dependent on the ATM kinase. p53 is phosphorylated by ATM shortly after DNA damage, resulting in enhanced stability and activity of p53. The Mdm2 oncoprotein is a pivotal negative regulator of p53. In response to ionizing radiation and radiomimetic drugs, Mdm2 undergoes rapid ATM-dependent phosphorylation prior to p53 accumulation. This results in a decrease in its reactivity with the 2A10 monoclonal antibody. Phage display analysis identified a consensus 2A10 recognition sequence, possessing the core motif DYS. Unexpectedly, this motif appears twice within the human Mdm2 molecule, at positions corresponding to residues 258-260 and 393-395. Both putative 2A10 epitopes are highly conserved and encompass potential phosphorylation sites. Serine 395, residing within the carboxy-terminal 2A10 epitope, is the major target on Mdm2 for phosphorylation by ATM in vitro. Mutational analysis supports the conclusion that Mdm2 undergoes ATM-dependent phosphorylation on serine 395 in vivo in response to DNA damage. The data further suggests that phosphorylated Mdm2 may be less capable of promoting the nucleo-cytoplasmic shuttling of p53 and its subsequent degradation, thereby enabling p53 accumulation. Our findings imply that activation of p53 by DNA damage is achieved, in part, through attenuation of the p53-inhibitory potential of Mdm2.

A temperature-jump apparatus with laser light sources was used to investigate the binding mechanism of indium(III) to pyrocathecol violet (3,3‘,4‘- trihydroxyfuchsone-2-sulfonic acid, whose neutral form is denoted as H4L). Spectrophotometric measurements revealed that for [H⁺] > 0.015 M, the main bound species are MH3L²⁺ and MH2L⁺ whereas for [H⁺] &lt; 0.015 M, the main bound species is M2L²⁺. Two relaxation effects were observed. The fast relaxation is associated mainly with the reaction steps M³⁺ + H3L^- ↔ MH3L²⁺ (k2 = 1.2 × 10⁶ M^-1 s^-1, k-2 = 1.5 × 10⁵ s^-1) and MOH²⁺ + H3L^- ↔ MH2L⁺ (k3 = 4.4 × 10⁷ M^-1 s^-1, k-3 = 7.4 × 10² s^-1). The rate constant k2 decreases, whereas k-2 increases, with increasing ionic strength. Addition of Na2SO4 results in a large reduction of the fast relaxation time that is ascribed to the binding of indium(III) to sulfate. Analysis of the relaxation time dependence on the sulfate concentration provides the binding constant of the indium−sulfate complex (K = 1.5 × 10² M^-1). The activation parameters for the step M³⁺ + H3L^- ↔ MH3L²⁺ were obtained as ΔH1f^&thermod; = 25.3 kJ mol^-1, ΔS1f^&thermod; = −6.2 J mol^-1 K^-1, ΔH1d^&thermod; = 13.4 kJ mol^-1, ΔS1d^&thermod; = −57 J mol^-1 K^-1. The enthalpy change of the just described reaction step was measured by spectrophotometry at different temperatures and by the relaxation amplitudes, the average value being ΔH1⁰ = 11.9 kJ mol^-1. The slow effect is associated with a complexation path leading to formation of M2L⁺. The amplitude analysis of the slow relaxation gives ΔH2⁰ = 7.6 kJ mol^-1. A comparison of this work with other studies on complexation with indium(III) suggests that In(OH)²⁺ reacts according to the Id mechanism, whereas the mode of activation of In(H2O)6³⁺ seems to be less definite because a clear indication about the dependence (or independence) of the rates on the ligand basicity does not emerge. This observation and the slightly negative value of ΔS1f^&thermod; hints at the possibility that indium(III) undergoes complexation by a concerted mechanism.

Abstract: Viable and total bacteria were determined during linear alkylbenzene sulfonate (LAS) degradation in coastal seawater. Viable bacteria were determined by plate counts on marine agar media, while total bacteria were determined by flow cytometry after SYTO-13 staining. LAS degradation was monitored by high-performance liquid chromatography analysis. Seawater samples with LAS at 5 mg/L, incubated in the laboratory (20C, 100 rpm, 30 d), showed in most cases a similar evolution in bacterioplankton abundance over time, characterized by three phases: (i) a progressive increase in bacterial density; (ii) a later decrease; and (iii) a fluctuating stationary phase. Bacterioplankton degraded the LAS by growing to populations with a high percentage of viable bacteria. The bacteria were rapidly grazed by protozoa, preventing anomalous high bacterial growth and ensuring the later channeling of LAS carbon to upper trophic levels.

The synthesis and evaluation of analogues of previously reported farnesyltransferase inhibitors, pyridyl benzyl ether 3 and pyridylbenzylamine 4, are described. Substitution of 3 at the 5-position of the core aryl ring resulted in inhibitors of equal or less potency against the enzyme and decreased efficacy in a cellular assay against Ras processing by the enzyme. Substitution of 4 at the benzyl nitrogen yielded 26, which showed improved efficacy and potency and yet presented a poor pharmacokinetic profile. Further modification afforded 30, which demonstrated a dramatically improved pharmacokinetic profile. Compounds 26 and 29 demonstrated significant in vivo efficacy in nude mice inoculated with MiaPaCa-2, a human pancreatic tumor-derived cell line.

The possibility of substitution of the conventional pentanol as cosurfactant by butyl lactate, on the preparation of OAV microemulsions in a system with SDS as anionic surfactant, is investigated. Whereas a narrow region of OAV microemulsion is described for the system with pentanol for a critical ratio 85/15 between water and SDS, butyl lactate leads to wider regions of solubility for different water/surfactant proportions, making easy the preparation of these microemulsions. Besides this advantage, being butyl lactate obtained from renewable resources and considered as a safe and biodegradable product, the microemulsions prepared with this cosurfactant could be applied in technological fields as cosmetic and dermopharmaceutical, where the biological agressivity of pentanol could avoid any practical application. As a complementary study, the influence that 1,3-buryleneglycol as polar cosolvent exert on the microemulsion regions, was also considered. Although according to experimental data given in the paper 1,3-butyleneglycol affects only slightly the OAV region of microemulsions, it can be foreseen that its presence could provide emollient characteristics to the final compositions.

Werner's syndrome is a human autosomal recessive disorder leading to premature aging. The mutations responsible for this disorder have recently been localized to a gene (WRN) encoding a protein that possesses DNA helicase and exonuclease activities. Patients carrying WRN gene mutations exhibit an elevated rate of cancer, accompanied by increased genomic instability. The latter features are also characteristic of the loss of function of p53, a tumor suppressor that is very frequently inactivated in human cancer. Moreover, changes in the activity of p53 have been implicated in the onset of cellular replicative senescence. We report here that the WRN protein can form a specific physical interaction with p53. This interaction involves the carboxyl-terminal part of WRN and the extreme carboxyl terminus of p53, a region that plays an important role in regulating the functional state of p53. A small fraction of WRN can be found in complex with endogenous p53 in nontransfected cells. Overexpression of WRN leads to augmented p53-dependent transcriptional activity and induction of p21(Waf1) protein expression. These findings support the existence of a cross-talk between WRN and p53, which may be important for maintaining genomic integrity and for preventing the accumulation of aberrations that can give rise to premature senescence and cancer.

TWEAK is a recently described member of the Tumor Necrosis Factor (TNF) ligand family whose transcripts are present in a wide variety of human tissues (Chicheportiche, Y., Bourdon, P. R., Xu, H., Hsu Y. M., Scott, H., Hession, C., Garcia, I., and Browning, J. L. (1997) J. Biol. Chem. 272, 32401-32410). TWEAK is a weak inducer of apoptosis in transformed cells when administered with interferon-gamma or cycloheximide (Chicheportiche, Y., Bourdon, P. R., Xu, H., Hsu Y. M., Scott, H., Hession, C., Garcia, I., and Browning, J. L. (1997) J. Biol. Chem. 272, 32401-32410; Masters, S. A., Sheridan, J. P., Pitti, R. M., Brush, A. G., and Ashkenazi, A. (1998) Curr. Biol. 8, 525-528) and also promotes IL-8 secretion in cultured cells. We report here that picomolar concentrations of recombinant soluble TWEAK induce proliferation in a variety of normal human endothelial cells and in aortic smooth muscle cells and reduce culture requirements for serum and growth factors. Blocking antibodies to Vascular Endothelial Growth Factor (VEGF) do not significantly inhibit TWEAK-induced proliferation, indicating that TWEAK does not function indirectly through up-regulation of VEGF. Pellets containing TWEAK induce a strong angiogenic response when implanted in rat corneas, suggesting a role for TWEAK in vasculature formation in vivo.

Summarizes several news events involving dolphins, including their possible use as Trident submarine guards, habitat destruction in the Amazon, and coastal and non-coastal migrations.

Previous work established a high correlation between the potential environmental toxicity of oxyethylenated nonionic surfactants and the average degree of ethoxylation. For this reason, it was considered of interest to determine whether a narrow- or broad-range homolog distribution of polydisperse commercial alcohol ethoxylates would influence toxicity. Ethoxylated fatty alcohols, both linear and branched, were synthesized with sodium hydroxide or an unconventional calcium-based catalyst. Toxicity tests were run onDaphnia magnaand luminescent marine bacteria. Toxicity of ethoxylated alcohols as a function of type of ethoxylate homolog distribution (narrow or broad) and average degree of polyaddition is analogous for both test species. However, narrow-range ethoxylates show lower toxicity values than conventional ethoxylates. Differences in toxicity values between broad- and narrow-range ethoxylates depend on the degree of ethoxylation.

The aim of this work has been to undertake a systematic study of wool chemical reactivity against sodium hypochlorite solutions at different pH levels in the absence and presence of surfactant solutions. The degradative effect on wool fibers of the oxidative treatments has been considered in terms of the cysteic acid formed as a consequence of cystine residue rupture. In addition, the adsorption of the surfactant by the fibers during the chlorination treatments has been determined, in an attempt to correlate both parameters (cysteic acid and surfactant adsorption) in order to op timize the process.

Hercosett resin was applied to untreated wool samples using dispersions made with a cationic Hercosett resin and different optical brightener agents in order to improve both brightness and shrinkproofing properties. The brighteners used in this work were Blankophor BA liq B, Uvitex CF-200, Univtex NFW, and Uvitex WGS. The physi cochemical properties of the dispersion systems were also investigated.

The physicochemical properties of dispersions made with the cationic resin Hercosett 57 and anionic surfactants have been investigated. The influence of the hydrocarbon chain and the anionic groups of surfactants has been investigated to determine the relationship between the components and their interactions. The application of resin surfactant complexes on untreated wool samples to confer shrink resistance has also been investigated.