Combined effect of natural antimicrobials and high pressure processing to prevent Listeria monocytogenes growth after a cold chain break during storage of cooked ham

The effect of high pressure processing (400 MPa for 10 min) and natural antimicrobials 2 (enterocins and lactate-diacetate) on the behaviour of L. monocytogenes in sliced cooked ham 3 during refrigerated storage (1ºC and 6ºC) was assessed. The efficiency of the treatments after a 4 cold chain break was evaluated. Lactate-diacetate exerted a bacteriostatic effect against L. 5 monocytogenes during the whole storage period (3 months) at 1ºC and 6ºC, even after 6 temperature abuse. The combination of low storage temperature (1ºC), high pressure 7 processing (HPP) and addition of lactate-diacetate reduced the levels of L. monocytogenes 8 during storage by 2.7 log CFU/g. The most effective treatment was the combination of HPP, 9 enterocins and refrigeration at 1ºC, which reduced the population of the pathogen to final counts 10 of 4 MPN/g after 3 months of storage, even after the cold chain break.

Influence of "historic" photoperiod during stem elongation on the number of fertile florets in wheat

Extending the duration of the late reproductive phase in wheat has been proposed as a possible avenue to improve spike fertility. There is a positive correlation between the number of fertile florets and the duration of the stem elongation phase when this phase is varied by extended photoperiod. Photoperiod treatments imposed during the vegetative period also influence the duration of stem elongation. The present study analysed the effect of long photoperiod (19 h) of different duration (10, 12, 14, 18 or 22 d) imposed before the onset of stem elongation on floret fertility in wheat. It was found that the length of the stem elongation phase was modified by earlier ‘historic ’ photoperiod treatments imposed during previous phases. However, neither the number of fertile florets per spike nor the spikelet fertility was affected significantly by these historic treatments. The results of the study therefore showed that an increased duration of the late reproductive phase was ineffective in increasing the number of fertile florets, unless the length of that phase was directly altered by current photoperiod.

Regional decomposition of CO2 emissions in the world: a cluster analysis

The purpose of this paper is to study the possible differences among countries as CO2 emitters and to examine the underlying causes of these differences. The starting point of the analysis is the Kaya identity, which allows us to break down per capita emissions in four components: an index of carbon intensity, transformation efficiency, energy intensity and social wealth. Through a cluster analysis we have identified five groups of countries with different behavior according to these four factors. One significant finding is that these groups are stable for the period analyzed. This suggests that a study based on these components can characterize quite accurately the polluting behavior of individual countries, that is to say, the classification found in the analysis could be used in other studies which look to study the behavior of countries in terms of CO2 emissions in homogeneous groups. In this sense, it supposes an advance over the traditional regional or rich-poor countries classifications .

Ultrastructural characterisation of the cell wall of Arabidopsis thaliana transgenic plants

The plant cell wall is a strong fibrillar network that gives each cell its stable shape. It is constituted by a network of cellulose microfibrils embedded in a matrix of polysaccharides, such as xyloglucans. To enlarge, cells selectively loosen this network. Moreover, there is a pectin-rich intercellular material, the middle lamella, cementing together the walls of adjacent plant cells. Xyloglucan endotransglucosylase/hydrolases (XTHs) are a group of enzymes involved in the reorganisation of the cellulose-xyloglucan framework by catalysing cleavage and re-ligation of the xyloglucan chains in the plant cell wall, and are considered cell wall loosening agents. In the laboratory, it has been isolated and characterised a XTH gene, ZmXTH1, from an elongation root cDNA library of maize. To address the cellular function of ZmXTH1, transgenic Arabidopsis thaliana plants over-expressing ZmXTH1 (under the control of the CaMV35S promoter) were generated. The aim of the work performed was therefore the characterisation of these transgenic plants at the ultrastructural level, by transmission electron microscopy (TEM).The detailed cellular phenotype of transgenic plants was investigated by comparing ultra-thin transverse sections of basal stem of 5-weeks old plants of wild type (Col 0) and 35S-ZmXTH1 Arabidopsis plants. Transgenic plants show modifications in the cell walls, particularly a thicker middle lamella layer with respect the wild type plants, supporting the idea that the overexpression of ZmXTH1 could imply a pronounced wall-loosening. In sum, the work carried out reinforces the idea that ZmXTH1 is involved in the cell wall loosening process in maize.  

Càlcul distribuït en BOINC per el trencament de l'algorisme RC5

Aquest projecte té com a objectiu participar en el desafiament d'RSA Laboratories corresponent a trencar el criptosistema RC5-32-12-9 proposat. Per realitzar-ho s'ha triat realitzar un atac per força bruta, mitjançant el càlcul distribuït i, més concretament, utilitzant la Public Resource Computing. La plataforma escollida és la Berkeley Open Infrastructure for Network Computing (BOINC), coneguda per la seva utilització en grans projectes com ara SETI@home. En aquest projecte es posa en funcionament la infraestructura i es desenvolupen les aplicacions necessàries per iniciar els càlculs que haurien de permetre el trencament del criptosistema.

Array de DNA per identificar espècies de Fusarium: ampliació d'un array existent per incloure espècies del Sud d'Europa

Projecte de recerca elaborat a partir d’una estada al Department for Feed and Food Hygiene del National Veterinary Institute, Noruega, entre novembre i desembre del 2006. Els grans de cereal poden estar contaminats amb diferents espècies de Fusarium capaces de produir metabolits secundaris altament tòxics com trichotecenes, fumonisines o moniliformines. La correcta identificació d’aquestes espècies és de gran importància per l’assegurament del risc en l’àmbit de la salut humana i animal. La identificació de Fusarium en base a la seva morfologia requereix coneixements taxonòmics i temps; la majoria dels mètodes moleculars permeten la identificació d’una única espècie diana. Per contra, la tecnologia de microarray ofereix l’anàlisi paral•lel d’un alt nombre de DNA dianes. En aquest treball, s’ha desenvolupat un array per a la identificació de les principals espècies de Fusarium toxigèniques del Nord i Sud d’Europa. S’ha ampliat un array ja existent, per a la detecció de les espècies de Fusarium productores de trichothecene i moniliformina (predominants al Nord d’Europa), amb l’addició de 18 sondes de DNA que permeten identificar les espècies toxigèniques més abundants al Sud d’Europa, les qual produeixen majoritàriament fumonisines. Les sondes de captura han estat dissenyades en base al factor d’elongació translació- 1 alpha (TEF-1alpha). L’anàlisi de les mostres es realitza mitjançant una única PCR que permet amplificar part del TEF-1alpha seguida de la hibridació al xip de Fusarium. Els resultats es visualitzen mitjançant un mètode de detecció colorimètric. El xip de Fusarium desenvolupat pot esdevenir una eina útil i de gran interès per a l’anàlisi de cereals presents en la cadena alimentària.

Crecimiento, instituciones e hidrocarburos : el proyecto petrolero mexicano en perspectiva histórica comparada (1938-2000)

En este trabajo se analiza la política petrolera mexicana durante el período 1938-2000 y su aportación al crecimiento económico mexicano. La orientación de la producción petrolera permite distinguir dos modelos de gestión de la industria petrolera. El primero de ellos; entre 1938-1976 tuvo por finalidad el aprovisionamiento energético del mercado interior a bajos precios. El segundo a partir de 1976 orientado hacia la exportación y la captura de la renta petrolera internacional. Esta ruptura en la política petrolera asociada constituye un caso interesante en sí mismo porque permite comparar los efectos de dos políticas totalmente opuestas sobre el crecimiento económico y sobre el desempeño de la propia industria petrolera en un país donde el Estado tiene derechos de propiedad exclusivos sobre el sector petrolero. Por ello, se aborda el tema como una problemática institucional que toma en cuenta tanto las características internas de México como la dinámica del mercado petrolero internacional. Se incide en el hecho de que el Estado mexicano ha utilizado a la industria petrolera y; concretamente los recursos que ésta genera no sólo como un instrumento para favorecer el crecimiento económico del país sino también para mantener el control del poder político frente a la élite económica. Así el inmovilismo institucional; la falta de ingresos e inversiones propias y el comportamiento rentista del Estado parecen haber condenado al sector petrolero mexicano al atraso y la ineficiencia. De este modo; se focaliza en las interrelaciones entre las instituciones económicas y políticas como elemento explicativo del por qué la industria petrolera no ha logrado convertirse en un elemento dinamizador del crecimiento económico mexicano en el largo plazo.

How does monetary policy change? evidence on inflation targeting countries

We examine the evolution of monetary policy rules in a group of inflation targeting countries (Australia, Canada, New Zealand, Sweden and the United Kingdom) applying moment- based estimator at time-varying parameter model with endogenous regressors. Using this novel flexible framework, our main findings are threefold. First, monetary policy rules change gradually pointing to the importance of applying time-varying estimation framework. Second, the interest rate smoothing parameter is much lower that what previous time-invariant estimates of policy rules typically report. External factors matter for all countries, albeit the importance of exchange rate diminishes after the adoption of inflation targeting. Third, the response of interest rates on inflation is particularly strong during the periods, when central bankers want to break the record of high inflation such as in the U.K. or in Australia at the beginning of 1980s. Contrary to common wisdom, the response becomes less aggressive after the adoption of inflation targeting suggesting the positive effect of this regime on anchoring inflation expectations. This result is supported by our finding that inflation persistence as well as policy neutral rate typically decreased after the adoption of inflation targeting.

Economic growth and inequality: the role of fiscal policies

This paper analyses the impact of different instruments of fiscal policy on economic growth as well as on income inequality, using an unbalanced panel of 43 upper-middle and high income countries for the period 1972-2006. We consider and estimate two individual equations explaining growth and inequality in order to assess the incidence of different fiscal policies. Firstly, our approach considers imposing orthogonal assumptions between growth and inequality in both equations, and secondly, it allows growth to be included in the inequality equation, and inequality to be included in the growth equation. The empirical results suggest that an increase in the size of government measured through current expenditures and direct taxes diminishes economic growth while reducing inequality, being public investment the only fiscal policy that may break this trade-off between efficiency and equity, since increases in this item reduces inequality without harming output. Therefore, the results reflect that the trade-off between efficiency and equity that governments often confront when designing their fiscal policies may be avoided.

ALK rearrangement in a selected population of advanced non small cell lung cancer patients. FISH and inmunohistochemistry diagnostic methods, prevalence and clinical outcomes

Anaplastic lymphoma kinase (ALK) rearrangements represents a new driver oncogenic event in non-small cell lung cancer (NSCLC). ALK positive patients account for a 1-7% of NSCLC patients. The objective of this study is to know the prevalence and clinical characteristics of ALK positive patients in a cohort of NSCLC patients and to compare inmunohistochemistry with D5F3 monoclonal antibody with gold standard method fluorescence in situ hybridation

The Franco-German motor before the eastern enlargement: the causes of its decline

The Franco-German axis has been a transcendent force behind the European integration ever since the early years of the EEC. Nevertheless, since the fall of the Berlin Wall in November 1989, the perception of a progressive distancing between France and Germany as far as the EU politics is concerned, has increased. There has not been a definitive break in Franco-German relations. However, the influence of the Franco-German axis in the EU has been reduced in the 90s. Finally, in the Nice IGC (December 2000), the misunderstandings of these two “big” states about their weight in the Council, almost caused the failure to conclude the Treaty of Nice, clearing the way for the Eastern enlargement. The traditional balance between France and Germany has been eroded. Germany has consolidated its role of leadership in the EU, and above all towards the candidate countries. The purpose of this paper is to analyse the fifth enlargement as one of the causes of the decline of the Franco-German axis as the motor of the process of European integration.

The Coherence of the European Foreign Policy: A Real Barrier or an Academic Term?

The purpose of the present study is to break down, in a general and summarised way, the concept of the coherence of the European Foreign Policy, in order to analyse its meaning, its scope and its implications. This focus on coherence will be specifically dealt with upon the analysis of the impact of this phenomenon on single institutional framework, as defined by the Treaty on European Union.

Management of corn stalk waste as reinforcement for polypropylene injection moulded composites

The main objective of this study was the management of corn stalk waste as reinforcement for polypropylene (PP) injection moulded composites as an alternative to wood flour and fibers. In the first step, corn stalk waste was subjected to various treatments, and four different corn stalk derivatives (flour and fibers) able to be used as reinforcement of composite materials were prepared and characterized. These derivatives are corn stalk flour, thermo-mechanical, semi-chemical, and chemical fibers. They were characterized in terms of their yield, lignin content, Kappa number, fiber length/diameter ratio, fines, coarseness, viscosity, and the length at the break of a standard sheet of paper. Results showed that the corn stalk derivatives have different physico-chemical properties. In the second step, the prepared flour and fibers were explored as a reinforcing element for PP composites. Coupled and non-coupled PP composites were prepared and tested for tensile properties. For overall trend, with the addition of a coupling agent, tensile properties of composites significantly improved, as compared with non-coupled samples. In addition, a morphological study revealed the positive effect of the coupling agent on the interfacial bonding. The composites prepared with semichemical fiber gave better results in comparison with the rest of the corn stalk derivatives due to its chemical characteristics

A Comparative study of germination strategies of two species of genus Allium sect. Allium

Germination experiments were performed with seeds of two species of genus Allium section Allium, a rare and endangered species A. pyrenaicum and a common A. sphaerocephalon. Different pre-treatments and a photoperiod of 24 h darkness were applied in order to simulate different germination conditions. Both species showed a high percentage of viable seeds a part of which were dormant. An elevate percentage of dormant seeds could be caused by a later collection time. Low altitude populations had more mortality than the others, possibly caused by the hard summer conditions during flowering and fruiting time. Comparisons between dates of species coexistence localities only show inter-population variability and it could be caused by the detected dormancy. Darkness accelerates germination, possibly for elongation radicle stimulation. Heat-shock pre-treatments decreased germination time in seeds from localities where fire is a probable event. The rarity of A. Pyrenaicum not seems to be caused by restricted germination requirements but is attributable to distinct habitat preferences, related to his altitudinal range of distribution

Variational calculation of vibrational linear and nonlinear optical properties

A variational approach for reliably calculating vibrational linear and nonlinear optical properties of molecules with large electrical and/or mechanical anharmonicity is introduced. This approach utilizes a self-consistent solution of the vibrational Schrödinger equation for the complete field-dependent potential-energy surface and, then, adds higher-level vibrational correlation corrections as desired. An initial application is made to static properties for three molecules of widely varying anharmonicity using the lowest-level vibrational correlation treatment (i.e., vibrational Møller-Plesset perturbation theory). Our results indicate when the conventional Bishop-Kirtman perturbation method can be expected to break down and when high-level vibrational correlation methods are likely to be required. Future improvements and extensions are discussed