Robustness of airline alliance route networks

The aim of this study is to analyze the robustness of the three major airline alliances’ (i.e., Star Alliance, oneworld and SkyTeam) route networks. Firstly, the normalization of a multi-scale measure of vulnerability is proposed in order to perform the analysis in networks with different sizes, i.e., number of nodes. An alternative node selection criterion is also proposed in order to study robustness and vulnerability of such complex networks, based on network efficiency. And lastly, a new procedure – the inverted adaptive strategy – is presented to sort the nodes in order to anticipate network breakdown. Finally, the robustness of the three alliance networks are analyzed with (1) a normalized multi-scale measure of vulnerability, (2) an adaptive strategy based on four different criteria and (3) an inverted adaptive strategy based on the efficiency criterion. The results show that Star Alliance has the most resilient route network, followed by SkyTeam and then oneworld. It was also shown that the inverted adaptive strategy based on the efficiency criterion – inverted efficiency – shows a great success in quickly breaking networks similar to that found with betweenness criterion but with even better results.Peer ReviewedPostprint (author’s final draft

Synthesis and reactivity of half-sandwich (η 5 -C 5 Me 5 )Ir(iii) complexes of a cyclometallated aryl phosphine ligand

Reaction of the Ir(iii) dimer [(η 5 -C 5 Me 5 )IrCl 2 ] 2 with PMeXyl 2 (Xyl = 2,6-C 6 H 3 Me 2 ), in the presence of the poorly coordinating base 2,2,6,6-tetramethyl piperidine, gives a chloride complex 1-Cl, resulting from hydrogen chloride elimination involving one of the phosphine benzylic hydrogen atoms and concomitant cyclometallation. Related compounds containing other halide or pseudohalide ligands, 1-Br, 1-Cl, 1-SCN, can be made, the latter featuring S-coordination of the ambidentate thiocyanate to the soft Ir(iii) Lewis acid centre, as suggested by IR data and demonstrated by X-ray crystallography. Hydride 2-H, and alkyl derivatives 3 (Me) and 4 (CH 2 SiMe 3 ) can also be prepared from 1-Cl and appropriate hydride and alkylating reagents. An interesting H/D exchange chemistry that occurs in the presence of CD 3 OD has been disclosed for 1-Cl, 1-Br and 2-H. For the halide derivatives, deuterium incorporation takes place into the methylene and methyl sites of their cyclometallated ligand, whereas for 2-H only the hydride and methylene (Ir-CH 2 ) protons participate in the exchange, which is strikingly accelerated by catalytic amounts of acids.Ministerio de Ciencia e Innovación CTQ2010-17476Consolider-Ingenio2010 CSD2007-0000Junta de Andalucia FQM-119, P09-FQM-483

Actinobacillus pleuropneumoniae and the development of an ELISA for the detection of ApxIV antibody in swine oral fluids

Swine respiratory diseases are of major concern to pork producers because of economic consequences related to reduced productivity, increased mortality, and the higher costs associated with prevention, control, treatments, and diagnoses. Actinobacillus pleuropneumoniae (APP) is the causative agent of porcine pleuropneumonia, a respiratory disease found throughout the world. Pigs are the primary host of APP and infection can occur at any age. APP infections are often acute and rapidly fatal, but chronic and/or subclinical infections occur. In particular, the latter play a role in perpetuating endemic infections in populations. A plethora of methods have been developed for the detection and/or diagnosis of APP, e.g., bacterial culture, antibody-based assays, and detection of nucleic acid targets using PCR. In particular, antibody detection provides an efficient, cost-effective approach for the surveillance of swine populations and several antibody assays have been developed, including ELISA assays based on polysaccharide antigen (capsular and LPS) and tests based on the detection of anti-toxin antibodies Apx I, ApxII, ApxIII, and ApxIV. Research has shown that the use of oral fluid specimens in diagnosis provides several advantages compared serum, including easier sample collection and better herd-level sensitivity and specificity (Olsen et al., 2013). Within this context, the focus of this thesis was on the development of an antibody ELISA for the detection of Actinobacillus pleuropneumoniae (APP) ApxIV toxin antibodies in swine oral fluid specimens. As described in Chapter 3, antibody responses specific for ApxIV in serum and oral fluid were compared in pigs inoculated with APP serovars 1, 5, 7, or 12 under experimental conditions using a commercial ApxIV antibody ELISA. The detection of antibodies in the oral fluid was achieved by adapting the serum ELISA protocol was adapted to the oral fluid matrix, as has been previously described (Kittawornrat et al., 2013). Serum samples were collected weekly and oral fluid samples were collected daily from individual pigs from day post inoculation (DPI) -14 through DPI 56. The LPS ELISA serum response showed that all pigs exposed to serovars 1 and 7 were positive from DPI 14 through DPI 56, with some animals demonstrating a LPS-specific IgG response as early as 7 DPI. In contrast, the LPS antibody response was transient or absent in pigs inoculated with serovars 5 and 12, suggesting that inoculation of pigs did not result in infection. Both IgM and IgG ApxIV serum antibody was detected in animals infected with serovars 1 and 7. Likewise, oral fluid samples from these animals showed a significant (p \u3c 0.05) ApxIV IgG response. Thus, this pilot experiment suggested that ELISAs based on the detection of ApxIV IgG antibody in oral fluid samples could be developed. Future work will be required to establish the ApxIV oral fluid ELISA cutoff and evaluate the application of the assay in the field

Dielectric and dynamic mechanical study of the mobility of poly(t-butylacrylate) chains in diblock copolymers: polystyrene-b-poly(t-butylacrylate)

A calorimetric, dielectric and dynamic-mechanical study of the dynamics of the poly(t-butyl acrylate) (PtBa) chains has been carried out in a PtBa homopolymer and two polystyrene (PS)-b-PtBa block copolymers with different PtBa chain lengths. The DSC results show that the size of the cooperative rearranging regions is similar in the homopolymers and the copolymers, both for the PtBa rich- and the PS-rich regions. Therefore, no significant contributions are found arising from composition fluctuations in the copolymers. The relaxation map obtained from dielectric relaxation indicates that there are no differences in the temperature dependence of the α-relaxation of the PtBa block in the three samples studied. However, there are larger differences for the values obtained from DMTA experiments. Contrary to the α-relaxation, the relaxation map for the β-transition shows that the characteristic times for the PtBa blocks are smaller in the homopolymer than in the copolymers. In principle, these are unexpected results because the β-relaxations have a more local character than the α-ones. The width of the α-relaxation increases with T for all the samples, and it is slightly larger for the copolymers. The intensity of the α-relaxation is larger (between 3 and 4 times) for the homopolymer. Considering the molecular weights of the PtBa blocks, this effect has to be ascribed to the existence of frozen amorphous PtBa due to the existence of the glassy PS domains in the microphase separated copolymers. Molecular Dynamic Simulations (MDSs) for different sequences of the polymers under study were carried out. The conformational analysis was carried out between 1000 and 1700 K. The analysis of the variation of angles 1 and 2 of the ester group of PtBa points out the existence of a correlation between the conformational changes of the side group of the polymer chains and their relaxational behaviour

Tasa de diagnóstico de pólipos en función de la indicación de la colonoscopia

El diagnóstico del CCR se establece con colonoscopia. Habitualmente esta se indica por la presencia de síntomas como es la rectorragia. El diagnóstico precoz del CCR se puede realizar a partir de la indicación de la colonoscopia, bien por la detección de sangre oculta en heces (SOH) o bien por la existencia de antecedentes familiares (AF). El pólipo de colon adenomatoso se considera una lesión pre-maligna y su resección es básica en la prevención del CCR. Nos proponemos comparar los hallazgos endoscópicos, concretamente la presencia de pólipos y de CCR, de los pacientes a los que se solicita la colonoscopia por rectorragia frente a los pacientes a los que se les solicita por AF o SOH. Se seleccionaron de forma consecutiva 100 pacientes a partir de una base de datos anonimizada del servicio de digestivo del Hospital Clínico Universitario de Valladolid. Cuarenta de ellos con rectorragia y 60 asintomáticos, divididos en 30 pacientes con AF y otros 30 pacientes con SOH. Se recogieron de forma retrospectiva, y a partir de los informes de las colonoscopias, se analizó la presencia, número, tamaño y tipo de los pólipos de colon, así como la presencia de CCR. El valor de p<0,05 fue considerado estadísticamente significativo. -Resultados: Al comparar los hallazgos de la colonoscopia en pacientes asintomáticos frente a pacientes con rectorragia no se han encontrado diferencias estadísticamente significativa en cuanto a la presencia de pólipos (48% vs 40%), pólipos mayores de 1 cm (20% vs 7,5%), o CCR (6% vs 10%). En la comparación de pacientes estudiados con colonoscopia por AF frente a los pacientes estudiados por SOH, la presencia de pólipos (33,3% vs 63,3%) y la presencia de pólipos > 1cm (6,7% vs 33,3%) fueron mayores en pacientes con SOH de forma estadísticamente significativa. Con respecto a la presencia de CCR, fue superior en los pacientes con SOH (0% vs 13,3%) con una diferencia que se aproximó mucho a la significación estadística (p 0,06). La frecuencia de pólipos o CCR no es mayor entre pacientes con rectorragia que en pacientes asintomáticos. El test de SOH positivo supone mayor tasa de diagnóstico de pólipos de colon, de pólipos mayores de 1 cm y de CCR que en caso de colonoscopia indicada por AF.Grado en Medicin

Silage for Cattle Feeding in Venezuela

Silage is the most economical food to guarantee animal feeding throughout the whole year. Lack of information, economic resources, and farming equipment restrain many farmers from applying this agro technology. Based on these reasons, the present research examines the current trends in animal food conservation in Venezuela. So far, si- lage is manufactured out of entire maize plants and silos store harvested pastures, forage grass independently culti- vated, and forage-legume mixture. The last feeding variant is highly profitable due to its excellent productive results and low costs. Nutrient contents in maize silage are dry matter (28 %-35 %) and raw protein (8.3 %-15.2 %). Ru- minal degradability levels range between 76 % and 82 % due to legume content and urea supplementation &nbsp;to the bulk. These findings&nbsp; are consistent &nbsp;with average &nbsp;milk production &nbsp;over 3 kg/cow/day &nbsp;and milk products&nbsp; sales. It should be noted that the best silage for cattle feeding consists of a grass-legume mixture in which legume content is not above 30 %

Simplified Hand Configuration for Object Manipulation

This work is focused on obtaining realistic human hand models that are suitable for manipulation tasks. Firstly, a 24 DOF kinematic model of the human hand is defined. This model is based on the human skeleton. Intra-finger and inter-finger constraints have been included in order to improve the movement realism. Secondly, two simplified hand descriptions (9 and 6 DOF) have been developed according to the constraints predefined. These simplified models involve some errors in reconstructing the hand posture. These errors are calculated with respect to the 24 DOF model and evaluated according to the hand gestures. Finally, some criteria are defined by which to select the hand description best suited to the features of the manipulation task