Theoretical study of the effect of substituent and backbone conformation on the electronic properties of symmetrically substituted poly(di‐n‐alkylsilanes)

We present the results of ab initio 3‐21G∗ geometry optimizations and valence effective Hamiltonian (VEH) band structure calculations aimed at determining the evolution of the geometric and electronic (ionization potential, electron affinities, and band gaps) properties of all‐trans poly(dimethylsilane), poly(diethylsilane), poly(di‐n‐propylsilane), and poly(di‐n‐butylsilane) when increasing the size of the alkyl group. In the latter polymer, we have also studied the 7/3 conformation, in order to analyze the effect of the backbone conformation on the geometric and electronic structure. The VEH ionization potentials of all‐trans poly(di‐n‐alkylsilanes) are almost equal, and as experimental photoemission data show, only slight differences are appreciated. The band gap decreases in going from poly(di‐n‐butylsilane) to poly(di‐n‐propylsilane) and to poly(diethylsilane), and increases when passing to poly(dimethylsilane), which coincides with experimental evidences on poly(di‐n‐alkylsilanes). The change from all‐trans to 7/3 conformation of poly(di‐n‐butylsilane) implies an increase of both, ionization potential and band gap, in perfect agreement with experimental photoemission and absorption data. The applicability of VEH to deal with poly(di‐n‐alkylsilanes) is [email protected]

Influencia del proceso de esterilización en la mojabilidad del titanio modificado superficialmente

El objetivo de este trabajo es estudiar el cambio en las propiedades energéticas de muestras de titanio comercialmente puro debido a distintos tratamientos superficiales y a distintos métodos de esterilización; con la finalidad de entender cómo afectan estos cambios a los procesos biológicos de los implantes de titanio. Los distintos tratamientos superficiales utilizados fueron: la formación de rugosidad mediante la proyección de partículas abrasivas, el granallado, y la esterilización mediante autoclave, óxido de etileno o radiación gamma. Tanto el nivel de rugosidad generada como la naturaleza de las partículas del granallado influyen en el carácter energético de las muestras; incrementando el carácter hidrofóbico con el aumento de la rugosidad y con la utilización de alúmina. Los contaminantes debidos al proceso de autoclave hidrofobizan las superficies; contrariamente a la esterilización por óxido de etileno que disminuye el valor del ángulo de contacto. La modificación de las superficies tratadas fue examinada con una serie de técnicas analíticas superficiales que incluyen el microscopio electrónico de barrido (SEM), la interferometría óptica y la medición del ángulo de contacto para poder realizar una caracterización topográfica, cualitativa y cuantitiva, y una caracterización energética, respectivamente.The aim of this work is to study the energetic properties of commercially pure titanium samples due to different surface treatments and different sterilization methods; with the purpose to understand how these changes affect to the biological processes of titanium implants. The different surface treatments were: roughness obtained by shot blasting, and sterilization by steam autoclaving, ethylene oxide or gamma radiation. Roughness level and the nature of the abrasive particles of shot blasting influence energetically the samples; increasing the hydrophobic behaviour with the increase of the surface roughness and the alumina use. The contamination due to steam autoclaving hydrophobizes the surface; contrary to sterilization by ethylene oxide, which reduces the contact angle value. The modification of treated surfaces was examined with a series of surface analytical techniques that include the scanning electron microscopy (SEM), the white light interferometer microscopy and the static contact angle measurement in order to determine a qualitative and quantitative topographic characterization and an energetic characterization

A pyrF auxotrophic mutant of Sinorhizobium fredii HH103 impaired in its symbiotic interactions with soybean and other legumes

Transposon Tn5-Mob mutagenesis allowed the selection of a Sinorhizobium fredii HH103 mutant derivative (SVQ 292) that requires the presence of uracil to grow in minimal media. The mutated gene, pyrF, codes for an orotidine-5´- monophosphate decarboxylase (EC 4.1.1.23). Mutant SVQ 292 and its parental prototrophic mutant HH103 showed similar Nod-factor and lipopolysaccharide profiles. The symbiotic properties of mutant SVQ 292 were severely impaired with all legumes tested. Mutant SVQ 292 formed small ineffective nodules on Cajanus cajan and abnormal nodules (pseudonodules) unable to fix nitrogen on Glycine max (soybean), Macroptitlium atropurpureum, Indigofera tinctoria, and Desmodium canadense. It also did not induce any macroscopic response in Macrotyloma axillare roots. The symbiotic capacity of SVQ 292 with soybean was not enhanced by the addition of uracil to the plant nutritive solution. [Int Microbiol 2007; 10(3):169-176

Reparación de lesiones del cartílago articular de la rótula de conejos con injertos libres de pericondrio costal y periostio tibial: Estudio histológico comparativo

El propósito del presente, estudio experimental es comparar la capacidad condrogénica de injertos libres de pericondrio y periostio en lesiones que afectan a todo el espesor del cartílago articular rotuliano. Para ellos, se eligieron 18 conejos adolescentes de Nueva Zelanda con un peso comprendido entre los 2400 y 3600 gramos, a los que se realizó una lesión de 6 mm de diámetro y 3 mm de espesor en la superficie articular de la rótula, y se distribuyeron de modo aleatorio en tres grupos: control, tratados con injerto libre de pericondrio (PC) y tratados con injerto libre de periostio (PO). Todos los animales fueron sacrificados a las 8 semanas y las preparaciones histológicas fueron evaluadas con arreglo a una escala que concede una puntuación de 0 a 17 puntos. En el análisis estadístico, las diferencias encontradas han sido, en todos los casos, entre el control y los grupos tratados, para ninguna de las variables se ha podido demostrar diferencias estadísticamente significativas entre los grupos PC y PO.The purpose of this experimental study was to compare the chondrogenic capacity of both perichondrium and periosteal free grafts in lesions affecting all the articular chondral thickness of the patella. A total of 18 white New Zeland rabbits with a weight ranging from 2.4 to 3.6 kg were operated. A chondral lesion o f 6 mm of diameter and 3 mm in depth was performed at the articular surface on the patella. The lesion was repair with either a perichondrium (6 animals) or a periosteal free grafts (6 animals). In other 6 animals, the control group, the lesion was not repaired. All animals were killed 8 weeks after surgery. Histological studies were performed using a modified O'Discoll's scale. Statistically significant differences were found between the control group and the two groups in which the lesions were repaired, but not between lesions treated with perichondrium and periosteal grafts

Humoral immune response of pregnant goats to two Corynebacterium pseudotuberculosis bacterin formulations

Caseous lymphadenitis is a chronic suppurative bacterial disease caused by Corynebacterium pseudotuberculosis, and it has a high prevalence among small ruminants. Different vaccine preparations have been employed to control this disease. The adjuvant used in the formulation is a critical factor for the improvement of vaccine efficacy. No commercial vaccines are available in Argentina. The aims of the present work were to compare the specific antibody response against a C. pseudotuberculosis whole cell vaccine formulated with a classical and an immunoestimulant adjuvant in pregnant goats, and to assess the transfer of vaccine-specific antibodies from the goat to the offspring through colostrum. Twenty three pregnant goats were vaccinated. The animals were randomly allocated to three groups: control, aluminum hydroxide Al(OH)3 adjuvant and a new cage-like particle adjuvant (ISPA). Antibodies (IgG) against this antigen were measured by ELISA. A robust humoral immune response was detected in vaccinated animals, with production of specific IgG. No significant differences were found between the vaccines formulated with different adjuvants. High levels of specific antibodies were detected in colostrum samples from both immunised groups, which were passively transferred from goats to offprings. No adverse local reactions in the vaccines injection sites were detected

Functional and genomic characterization of Komagataeibacter uvaceti FXV3, a multiple stress resistant bacterium producing increased levels of cellulose

Funding Information: This work was supported by the Applied Molecular Biosciences Unit - UCIBIO which is financed by national funds from FCT ( UIDB/04378/2020). Funding Information: Funding from INTERFACE Programme, through the Innovation, Technology and Circular Economy Fund (FITEC), is gratefully acknowledged. Publisher Copyright: © 2021Bacterial cellulose is one of the most promising biomaterials for the development of a wide array of novel biotechnological solutions. Nevertheless, the commercial production of bacterial cellulose is still a challenge and obtaining novel strains presenting increased cellulose biosynthesis and stress resistance properties is of extreme importance. This work demonstrates the increased stress resistance, cellulose production abilities, and overall genomic properties of Komagataeibacter uvaceti FXV3, a novel cellulose-producing and stress resistant strain isolated from a fermented grape must. K. uvaceti FXV3 was able to grow under several stress conditions, including the presence of high concentrations of ethanol (up to 7.5 % v/v), a trait that is not observed in the model strain K. xylinus CECT 7351T. Moreover, K. uvaceti FXV3 produced increased concentrations of cellulose (4.31 mg/mL, 7 days after inoculation-DAI) when compared to K. xylinus CECT 7351T (1.42 mg/mL, 7 DAI). Moreover, the detailed analysis of strain FXV3 genome revealed the presence of several genes involved in cellulose and acetan biosynthesis, quorum-sensing and quenching mechanisms, carbohydrate, amino acid, alcohol and aldehyde metabolism, as well as several other genes involved in stress resistance. Additionally, comparative genomic analysis revealed the increased prevalence of stress resistance genes in K. uvaceti FXV3 when compared to K. xylinus CECT 7351T. Ultimately, this study reveals the increased biotechnological potential of K. uvaceti FXV3 and brings new insights into the genetics behind Komagataeibacter stress resistance and cellulose production abilities.publishersversionpublishe

Numerical Model of Constrained Wave Energy Hyperbaric Converter under Full-Scale Sea Wave Conditions

Funding Information: This research was funded by Fundação para a Ciência e a Tecnologia (FCT.IP) through the grant UIDB/00667/2020 (UNIDEMI). This work was also supported by the project SURVIWEC PID2020-113245RB-I00 and by the project ED431C 2021/44 “Programa de Consolidación e Estructuración de Unidades de Investigación Competitivas”. This study forms part of the Marine Science programme (ThinkInAzul) supported by Ministerio de Ciencia e Innovación and Xunta de Galicia with funding from the European Union NextGenerationEU (PRTR-C17.I1) and European Maritime and Fisheries Fund. Funding Information: The authors acknowledge Fundação para a Ciência e a Tecnologia (FCT.IP) for its financial support through the grant UIDB/00667/2020 (UNIDEMI). This work was also supported by the project SURVIWEC PID2020-113245RB-I00 financed by MCIN/AEI/10.13039/501100011033 and by the project ED431C 2021/44 ”Programa de Consolidación e Estructuración de Unidades de Investigación Competitivas” financed by Xunta de Galicia, Consellería de Cultura, Educación e Universidade. This study forms part of the Marine Science programme (ThinkInAzul) supported by Ministerio de Ciencia e Innovación and Xunta de Galicia with funding from the European Union NextGenerationEU (PRTR-C17.I1) and European Maritime and Fisheries Fund. Publisher Copyright: © 2022 by the authors.A 2D numerical investigation of the power absorption of a constrained wave energy hyperbaric converter (WEHC) under full-scale sea wave conditions is presented. A fully non-linear numerical model DualSPHysics, based on the coupling of a smoothed particle hydrodynamics (SPH) fluid solver with a multibody dynamics solver, is used to model the interaction between wave and WEHC sub-systems. The numerical model was first validated against experimental data for a similar device, with a good accordance between PTO position and velocity. The model is then employed to study the hydrodynamics of a constrained WEHC considering several sea states, different hydraulic power take-off (PTO) damping and breakwater geometries. It is observed that the capture width ratio (CWR) is particularly sensitive to variations in the PTO damping, although the CWR absolute maximum is less sensitive considering mild variations applied to the PTO damping. Both wave height and wave period have an important effect on the CWR. The breakwater geometry is also essential for the performance of the WEHC, with a decrease in maximum CWR of about 15% for porous breakwater. These results are necessary to understand the full-scale behaviour of WEHC.publishersversionpublishe

Humoral immune response of pregnant goats to two Corynebacterium pseudotuberculosis bacterin formulations

Caseous lymphadenitis is a chronic suppurative bacterial disease caused by Corynebacterium pseudotuberculosis with a high prevalence in small ruminants. Different vaccine preparations have been employed to control this disease. The adjuvant used in the formulation is a critical factor for the improvement of vaccine efficacy. No commercial vaccines are available in Argentina. The aims of the present work were to compare the specific antibody response against a C. pseudotuberculosis whole cell vaccine formulated with a classical and an immunoestimulant adjuvant in pregnant goats, and to assess the transfer of vaccine- specific antibodies from the goat to the offspring through colostrum. Twenty three pregnant goats were vaccinated. The animals were randomly allocated to three groups: control, aluminum hydroxide Al(OH)3 adjuvant and a new cage-like particle adjuvant (ISPA). Antibodies (IgG) against this antigen were measured by ELISA. A robust humoral immune response was detected in vaccinated animals, with production of specific IgG, without finding significant differences between the vaccines formulated with different adjuvants. High levels of specific antibodies were detected in colostrum samples from both immunized groups, which were passively transfered from goats to offprings. No adverse local reactions in the vaccines injection sites were detected.Fil: Auad, Jordana. Universidad Católica de Córdoba; ArgentinaFil: Cerutti, Julieta. Universidad Católica de Córdoba; ArgentinaFil: Cooper, Laura Gabriela. Universidad Católica de Córdoba; ArgentinaFil: Camussone, Cecilia María. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Santa Fe. Estación Experimental Agropecuaria Rafaela; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; ArgentinaFil: Lozano, Natalia A.. Universidad Católica de Córdoba; ArgentinaFil: Crespo, Francisco M.. Establecimiento Los Talas. Potrero de Garay, Córdoba; ArgentinaFil: Lozano, Alejandro. Universidad Católica de Córdoba; Argentin

Improvements of Fire Fuels Attributes Maps by Integrating Field Inventories, Low Density ALS, and Satellite Data in Complex Mediterranean Forests

One of the most determining factors in forest fire behaviour is to characterize forest fuel attributes. We investigated a complex Mediterranean forest type—mountainous Abies pinsapo–Pinus–Quercus–Juniperus with distinct structures, such as broadleaf and needleleaf forests—to integrate field data, low density Airborne Laser Scanning (ALS), and multispectral satellite data for estimating forest fuel attributes. The three-step procedure consisted of: (i) estimating three key forest fuel attributes (biomass, structural complexity and hygroscopicity), (ii) proposing a synthetic index that encompasses the three attributes to quantify the potential capacity for fire propagation, and (iii) generating a cartograph of potential propagation capacity. Our main findings showed that Biomass–ALS calibration models performed well for Abies pinsapo (R2 = 0.69), Juniperus spp. (R2 = 0.70), Pinus halepensis (R2 = 0.59), Pinus spp. mixed (R2 = 0.80), and Pinus spp.–Juniperus spp. (R2 = 0.59) forests. The highest values of biomass were obtained for Pinus halepensis forests (190.43 Mg ha−1). The structural complexity of forest fuels was assessed by calculating the LiDAR Height Diversity Index (LHDI) with regard to the distribution and vertical diversity of the vegetation with the highest values of LHDI, which corresponded to Pinus spp.–evergreen (2.56), Quercus suber (2.54), and Pinus mixed (2.49) forests, with the minimum being obtained for Juniperus (1.37) and shrubs (1.11). High values of the Fuel Desiccation Index (IDM) were obtained for those areas dominated by shrubs (−396.71). Potential Behaviour Biomass Index (ICB) values were high or very high for 11.86% of the area and low or very low for 77.07%. The Potential Behaviour Structural Complexity Index (ICE) was high or very high for 37.23% of the area, and low or very low for 46.35%, and the Potential Behaviour Fuel Desiccation Index (ICD) was opposite to the ICB and ICE, with high or very high values for areas with low biomass and low structural complexity. Potential Fire Behaviour Index (ICP) values were high or very high for 38.25% of the area, and low or very low values for 45.96%. High or very high values of ICP were related to Pinus halepensis and Pinus pinaster forests. Remote sensing has been applied to improve fuel attribute characterisation and cartography, highlighting the utility of integrating multispectral and ALS data to estimate those attributes that are more closely related to the spatial organisation of vegetation

Coupling to breakup channels using a transformed harmonic oscillator basis

The application of a recently proposed procedure for discretizing the continuum to collision processes involving weakly bound nuclei is studied. In particular, the coupling to breakup states in the collision of d+208Pb at 50 MeV is discussed. For illustrative purposes, only the s-wave component of the bound state of the deuteron is considered, and the study is restricted to the case of nuclear s-wave breakup. The continuum discretization procedure provides a basis of transformed harmonic oscillator wave functions to accomplish the necessary calculations. Appropriate convergence of the elastic and breakup cross sections with increasing dimension of the basis is reported. In addition, it is shown that the results obtained converge to those of a standard continuum discretized coupled channels calculation, with the advantage that the convergence of the method is determined by only one parameter, namely the dimension of the basis.Ministerio de Ciencia y Tecnología PB98- 1111 FP A2000-1592-C03-02Portuguese Science and Technology Foundation SAPIENS/36282/9