Nitrogenase activity associated with codium species from New Zealand marine habitats

Nitrogenase activity, measured as acetylene reduction, was recorded at rates up to 1028 nmol.h \g * dry weight for Codium adhaerens (Cabr.) Ag. var. convolutum Dellow and Codium fragile (Sur.) Hariot subsp. tomentosoides (Van Goor) Silva collected from New Zealand habitats. In both species the ability to reduce acetylene is invariably associated with the presence of a heterocystous blue-green alga, Calothrix sp., epiphytic or embedded in the Codium thallus. A highly significant (P < 0.001) correlation between heterocyst frequency and nitrogenase activity was found. Nitrogenase and net photosynthesis of the Codium-Calothrix system have different steady-state responses to light intensity, and the kinetics of the two processes also differ in that nitrogenase is slow to respond to illumination or darkening. Glucose additions to Codium did not significantly increase nitrogenase activity. Nitrogenase is relatively insensitive to oxygen tension over the range 0-1.0 atm (0-1.033 kgf.cnT2) and still occurs at 1.5 atm (1.55 kgf.cm"2); this condition is unique in all nitrogenase systems thus far reported. Collectively these facts suggest that Calothrix is the agent primarily responsible for nitrogenase activity in these Codium species

Pulsational frequencies of the eclipsing delta-Scuti star HD 172189

The eclipsing delta-Scuti star HD 172189 is a probable member of the open cluster IC 4756 and a promising candidate target for the CoRoT mission. The detection of pulsation modes is the first step in the asteroseismological study of the star. Further, the calculation of the orbital parameters of the binary system allows us to make a dynamical determination of the mass of the star, which works as an important constraint to test and calibrate the asteroseismological models. From a detailed frequency analysis of 210 hours of photometric data of HD 172189 obtained from the STEPHI XIII campaign we have identified six pulsation frequencies with a confidence level of 99% and a seventh with a 65% confidence level in the range between 100-300 uHz. In addiction, three eclipses were observed during the campaign, allowing us to improve the determination of the orbital period of the system.Comment: 6 pages, 7 figure

Implementación de una herramienta multiplataforma con Google Workspace para optimizar el control de producción en la Unidad Minera Constancia, Hudbay Perú S.A.C.

El uso adecuado de recursos humanos y equipos en una empresa minera viene digitalizándose con el tiempo para mejorar su control de producción. Este estudio tuvo el objetivo de implementar una Herramienta multiplataforma Workspace de Google en la Unidad Minera Constancia, Hudbay Perú. Esto se logra optimizando los principales indicadores de producción para mejorar el proceso de extracción y movimiento de material. Como muestra se tomó a 20 colaboradores de la oficina Control Mina, quienes son encargados de llevar el control total de la empresa en materia logística para tomar decisiones operativas. Este estudio fue de enfoque cuantitativo, de diseño cuasiexperimental, de corte transversal, de tipo hipotético-deductivo. Se elaboró cuestionario como instrumento denominado “Cuestionario de Medición de Control de Producción Minera” que fue sometido a prueba de confiabilidad, resultando en un alfa de Cronbach en Pre Test de 0.851 y 0.877 en Post Test. La metodología aplicada para los objetivos específicos consistió en una primera etapa la construcción del instrumento para luego evaluar el Pre Test (Antes) y Post Test (Después) para las 4 dimensiones (Captación de datos, organización, Precisión y Comunicación) haciendo una comparación estadística para cada dimensión. Este estudio tuvo como resultado que los colaboradores de la oficina Control Mina evaluaron el Pre Test en un 10% de satisfacción en el control de producción minera a pasar a un 80% de satisfacción gracias a la Herramienta multiplataforma. Asimismo, demostrándose estadísticamente con la prueba de Wilcoxon del Pre Test y Post Test con una significancia asintótica bilateral de la prueba de Wilcoxon resultó con un p-valor (0,000), que confirma estadísticamente que existió mejora en el Control de producción minera tanto en la captación, organización, precisión de datos y comunicación entre equipos

Risks to human and animal health related to the presence of deoxynivalenol and its acetylated and modified forms in food and feed

Peer reviewedPublisher PD

Crack tip fields in elastic-plastic and mixed mode I+II+III conditions, finite elements simulations and modeling

This paper is devoted to the analysis of the load path effect on I+II+III mixed mode fatigue crack propagation in a 316L stainless steel. Experiments were conducted in mode I+II and in mode I+II+III. The same maximum, minimum and mean values of the stress intensity factors were used for each loading path in the experiments. The main result of this set of experiments is that very different crack growth rates and crack paths are observed for load paths that are however considered as equivalent in most fatigue criteria. The experiments conducted in mode I+II and in mode I+II+III, also allowed to show that the addition of mode III loading steps to a mode I+II loading sequence is increasing the fatigue crack growth rate, even when the crack path is not significantly modified

2005 French Salmonella Network data on antimicrobial resistance in the swine channels

The Salmonella Network is gathering, on a voluntary participation scheme, from approximately 150 public and private laboratories dissemmated throughout France, Salmonella strains and/or epidemiological information. Those non-human Salmonella strains are isolated either from animal health and production or food, feed and the environment sectors. Thus, in 2005, a total of 527 isolations from the swine channels were reported. The top 5 prevalent serotypes were : Typhimurium, Derby, Manhattan, lnfantis and Kedougou. Two-hundred and ninety five strains were received at the laboratory and, after double clearance, 185 strains were tested for their antimicrobial resistance against 16 antibiotics by the disk diffusion method. Twenty-one strains were associated to the animal health and production sector and 164 to the food sector

Blood co-expression modules identify potential modifier genes of diabetes and lung function in cystic fibrosis

A fibrose cística (FC) é uma doença genética rara que afeta os sistemas respiratório e digestivo. A doença pulmonar é variável entre pacientes com FC e está associada ao desenvolvimento de comorbidades e infecções crônicas. A taxa de deterioração da função pulmonar depende não apenas do tipo de mutações no CFTR, o gene causador da doença, mas também de genes modificadores. No presente estudo, objetivamos identificar genes e vias que (i) contribuem para a patogênese da fibrose cística e (ii) modulam as comorbidades associadas. Fizemos o perfil de amostras de sangue em pacientes com FC e controles saudáveis ​​e analisamos dados de RNA-seq com Weighted GeneCorrelation Network Analysis (WGCNA). Curiosamente, a função pulmonar, o índice de massa corporal, a presença de diabetes e infecções crônicas por P. aeruginosa se correlacionaram com quatro módulos de genes coexpressos. A inspeção detalhada de redes e genes centrais apontou para adesão celular, tráfego de leucócitos e produção de espécies reativas de oxigênio como mecanismos centrais no declínio da função pulmonar e diabetes relacionado à fibrose cística. Vale ressaltar que mostramos que o sangue é um tecido substituto informativo para estudar a contribuição da inflamação para a doença pulmonar e diabetes em pacientes com FC. Finalmente, fornecemos evidências de que o WGCNA é útil para analisar conjuntos de dados ômicos em doenças genéticas raras, pois as coortes de pacientes são inevitavelmente pequenas.Cystic fibrosis (CF) is a rare genetic disease that affects the respiratory and digestive systems. Lung disease is variable among CF patients and associated with the development of comorbidities and chronic infections. The rate of lung function deterioration depends not only on the type of mutations in CFTR, the disease-causing gene, but also on modifier genes. In the present study, we aimed to identify genes and pathways that (i) contribute to the pathogenesis of cystic fibrosis and (ii) modulate the associated comorbidities. We profiled blood samples in CF patients and healthy controls and analyzed RNA-seq data with Weighted GeneCorrelation Network Analysis (WGCNA). Interestingly, lung function, body massindex, the presence of diabetes, and chronic P. aeruginosa infections correlated with four modules of co-expressed genes. Detailed inspection of networks and hub genes pointed to cell adhesion, leukocyte trafficking and production of reactive oxygen species as central mechanisms in lung function decline and cystic fibrosis-related diabetes. Of note, we showed that blood is an informative surrogate tissue to study the contribution of inflammation to lung disease and diabetes in CF patients. Finally, we provided evidence that WGCNA is useful to analyze–omic datasets in rare genetic diseases as patient cohorts are inevitably small

Les Laboratoires de chimie

Data del Supplément: 1882Pag.: v.1: 145 p.; v.2: 74 p.; v.3: [81] f. de làm.Conté: v. 1: Texte -- v. 2: Supplément / Henrivaux, Girard et Pabst -- v. 3: Atla

What's in a name? - A short history of coordination chemistry from then to now

This article traces the development of coordination chemistry and shows how progress in the science has been paralleled by the development of a vocabulary and nomenclature to describe new concepts, structural features and compound types

Risks to human and animal health related to the presence of moniliformin in food and feed

The CONTAM Panel wishes to acknowledge all European competent authorities and other stakeholders that provided occurrence data on moniliformin in food and feed, and supported the consumption data collection for the Comprehensive European Food Consumption Database. Adopted: 21 November 2017Peer reviewedPublisher PD