Natural product diversity of actinobacteria in the Atacama Desert

Natural Product diversityPeer reviewedPublisher PD

Horizontal wind perturbations and their relation to transient internal gravity waves

Horizontal winds as measured with the Saskatoon MF radar exhibit wind fluctuations which have preferred directions toward north or south in the period range 0 to 60 min at heights between about 60 and 110 km. Longer period perturbations (approx 1-6 h) tend to have an additional maximum of direction frequencies in the E-W sector.The polarization effect analyzed for more than 6 years shows regular changes with season. The main features of the seasonal variations of the direction distributions can be explained by directional filtering of vertically propagating nonstationary gravity waves and appropriate changes of the wave source strength and position in the troposphere. The N-S polarization of the gravity-wave field appears to result in meridional wind reversals with height above the mesopause

Geopolítica del petróleo en Eurasia

En el contexto actual, la seguridad nacional y la seguridad energética están tan estrechamente relacionadas que es imposible plantearlas como dos cuestiones distintas. En primer lugar hay que preguntarse a qué nos referimos cuando hablamos de seguridad nacional. Propongo la que, en mi opinión, es la mejor definición del término. Hace ya unos años el ilustre diplomático estadounidense George Kennan formuló la definición probablemente más clara: seguridad nacional se refiere a ‘la capacidad de este país para proseguir con su vida interna sin graves interferencias’. Queda entonces por acotar el término seguridad energética. Para el consumidor estadounidense la respuesta es sencilla, ya que únicamente le preocupan dos cosas: el precio y la disponibilidad. Poco más importa, y resulta irrelevante si el petróleo que se consume es de origen nacional o si ha sido importado. Con toda probabilidad, estas preocupaciones son extensibles a los consumidores del resto del mundo. Sin embargo, los gobiernos importadores deben adoptar una perspectiva distinta y aspirar a la seguridad energética (o la seguridad de abastecimiento) mediante la diversidad del suministro, así como a la diversidad de los tipos de combustible que se consumen. Las opciones de seguridad energética de que dispone cualquier nación importadora de petróleo o gas son limitadas. Los países importan porque las necesidades internas son superiores a sus capacidades de producción. EEUU, por ejemplo, importa petróleo de alrededor de 60 proveedores distintos. Aunque medir la diversidad de esta forma nos conduciría a engaño, puesto que no nos dejaría ver el peso específico que ocupan el Golfo Pérsico, en concreto, y la Organización de Países Exportadores de Petróleo (OPEP) en general. La búsqueda de nuevos suministros de crudo fuera del Golfo Pérsico prosigue en un intento por maximizar la diversidad de las fuentes de suministro, aunque todavía no se haya encontrado un sustituto total, y posiblemente nunca se encuentre

Kinetic energy budgets in areas of intense convection

A kinetic energy budget analysis of the AVE-SESAME 1 period which coincided with the deadly Red River Valley tornado outbreak is presented. Horizontal flux convergence was found to be the major kinetic energy source to the region, while cross contour destruction was the major sink. Kinetic energy transformations were dominated by processes related to strong jet intrusion into the severe storm area. A kinetic energy budget of the AVE 6 period also is presented. The effects of inherent rawinsonde data errors on widely used basic kinematic parameters, including velocity divergence, vorticity advection, and kinematic vertical motion are described. In addition, an error analysis was performed in terms of the kinetic energy budget equation. Results obtained from downward integration of the continuity equation to obtain kinematic values of vertical motion are described. This alternate procedure shows promising results in severe storm situations

Dual Induction of New Microbial Secondary Metabolites by Fungal Bacterial Co-cultivation

We thank the College of Physical Sciences, University of Aberdeen, for provision of infrastructure and facilities in the Marine Biodiscovery Centre. We acknowledge the receipt of funding from the European Union’s Seventh Programme for Research, Technological Development and Demonstration under Grant Agreement No. 312184 (PharmaSea). MR thanks School of Science and Sport, University of the West of Scotland for providing the open-access fees required for the publication.Peer reviewedPublisher PD

Alcohol Interventions for Trauma Patients Treated in Emergency Departments and Hospitals: A Cost Benefit Analysis

Summarizes a study of whether screening for problem drinking and interventions to reduce alcohol intake in hospital trauma centers reduce the direct cost of injury-related health care. Compares the costs of injury recidivism with and without intervention

Numerical investigation of a double frequency approach for longitudinal HF welding of cladded pipes

This article contains findings of simulation research on longitudinal induction welding of cladded pipes with use of simultaneous double frequency. Solutions are proposed to reach the required temperature distribution at the welding edge for the cladding composite of S355 and Alloy 625 with single and simultaneous double frequency. An advanced consideration of magnetic and other material properties was performed to simulate the dominating physical effects of high frequency (HF) welding. The background of use and advantages of simultaneous double frequency are presented. In the context of the research, a correlation for welding speed, frequency and temperature distribution with industrial relevance was found for the cladded pipe welding

Soil-water dynamics and unsaturated storage during snowmelt following wildfire

Many forested watersheds with a substantial fraction of precipitation delivered as snow have the potential for landscape disturbance by wildfire. Little is known about the immediate effects of wildfire on snowmelt and near-surface hydrologic responses, including soil-water storage. Montane systems at the rain-snow transition have soil-water dynamics that are further complicated during the snowmelt period by strong aspect controls on snowmelt and soil thawing. Here we present data from field measurements of snow hydrology and subsurface hydrologic and temperature responses during the first winter and spring after the September 2010 Fourmile Canyon Fire in Colorado, USA. Our observations of soil-water content and soil temperature show sharp contrasts in hydrologic and thermal conditions between north- and south-facing slopes. South-facing burned soils were ∼1–2 °C warmer on average than north-facing burned soils and ∼1.5 °C warmer than south-facing unburned soils, which affected soil thawing during the snowmelt period. Soil-water dynamics also differed by aspect: in response to soil thawing, soil-water content increased approximately one month earlier on south-facing burned slopes than on north-facing burned slopes. While aspect and wildfire affect soil-water dynamics during snowmelt, soil-water storage at the end of the snowmelt period reached the value at field capacity for each plot, suggesting that post-snowmelt unsaturated storage was not substantially influenced by aspect in wildfire-affected areas. Our data and analysis indicate that the amount of snowmelt-driven groundwater recharge may be larger in wildfire-impacted areas, especially on south-facing slopes, because of earlier soil thaw and longer durations of soil-water contents above field capacity in those areas