Vitalität oder Zerfall? Der Gurkentest - eine neue Methode

Um herauszufinden, wie gut die Qualität von Gurken ist, wurde ein Vitalitätstest erfunden: Gurken werden in ca. 2 cm dicke Scheiben geschnitten, in transparente Plastikfolie gewickelt und in einen Inkubator gelegt. Nach einigen Tagen zeigt sich, welche Gurken mikrobiell angegriffen wurden oder an den Schnittflächen zusammengewachsen sind. Dieses Vorgehen wird beliebig oft wiederholt. Die Untersuchungen nach dieser Methode ergaben, dass alte Sorten und biologisch bzw. bio-dynamisch angebaute Gurken am vitalsten sind. Sie zeigten teilweise erst nach zweieinhalb Monaten einen Befall durch Mikroorganismen. Die wieder zusammengewachsenen Schnittfläche können sogar mit mehr als 2 kg belastet werden

Resultados polínicos del Holoceno en la Península Ibérica

El interés que en los últimos años ha adquirido en Europa Occidental el análisis de polen como ayuda al prehistoriador, nos ha llevado a recopilar los datos que tenemos en la Península Ibérica sobre el Holoceno o Postglaciar. Aunque los datos son escasos, y en algunos casos insuficientes, sobre todo para algunas regiones, en general aportan elementos de juicio para que en un futuro no lejano pueda establecerse una secuencia completa, como en el resto de Europa. La evidencia de la sucesión de muchos tipos de asociaciones vegetales en el seno de una unidad geográfica, nos ha conducido a corroborar hipótesis cronoestratigráficas, emitidas anteriormente por los prehistoriadores. Los resultados de la Palinología aplicada a los depósitos arqueológicos ofrecen el interés de dar una imagen parcial, pero significativa, del paisaje vegetal que sirsió de cuadro cotidiano al hombre, y el de evocar a través de este paisaje cierto tipo de clima.Peer reviewe

A priori estimates in terms of the maximum norm for the solutions of the Navier–Stokes equations

AbstractIn this paper, we consider the Cauchy problem for the incompressible Navier–Stokes equations with bounded initial data and derive a priori estimates of the maximum norm of all derivatives of the solution in terms of the maximum norm of the initial velocity field. For illustrative purposes, we first derive corresponding a priori estimates for certain parabolic systems. Because of the pressure term, the case of the Navier–Stokes equations is more difficult, however

Snow creep pressure on mast constructions

In Norway snow-creep quite often causes damage on mast constructions on hillsides exposed to deep snow-cover. An extensive snow-creep measurement program has therefore been carried out for different constructions at NGI's snow and avalanche research station in Grasdalen during the period 1975 to 1990. Examples from power-line masts and ski-lift masts are shown to illustrate the snow-creep pressure problem. The aim of the research project is to be able to draw up guidelines for the design of masts in snow-creep exposed areas

Organic Food and Health: A new project to study the effects of plant cultivation methods (organic and conventional) on nutritional value, health and reproduction in an animal experiment

Many consumers believe that food from plants grown under certain conditions, such as organic agriculture, will benefit health more than conventional food. This cannot be determined simply by analysing the material, since our understanding of the connections between food components and health is still to imprecise for such a purpose. Rather than waiting until basic research provides the knowledge needed for this approach, in the spring of 2001 we have initiated a project to study physiological effects of plant quality directly, in an animal experiment. The following cultivation treatments are used to grow plants that are typical ingredients for a human diet (potato, mature peas, kale, spring wheat, oilseed rape, carrots and apples): 1. A model of a distinct conventional cultivation system, with high input of mineral nutrients and use of as much pesticides as is allowed. 2. A model of a distinct organic cultivation system, with low input of organic plant nutrients and no use of pesticides. 3. A combination of model 1 and 2, with low input of nutrients and use of pesticides. The materials from each cultivation treatment will be thoroughly characterised, by measuring contents of nutrients (protein, minerals, energy content, vitamins), the biological value of major protein sources of feed plants will be assessed, selected secondary metabolites including known anti-nutrients will be measured and other quality indicators will be assessed including biocrystallization. Based on these results, 3 feed mixtures will be prepared, either based on defined weight percentages of each material from each treatment, or, if large variation in biological value is found, one or two feed mixtures can be adjusted to provide the same availability of protein and energy as the reference treatment (model 1). Potato, mature peas and kale will be cooked and freeze-dried, wheat is ground and baked to biscuits, oil is produced from the rapeseed, and raw carrots and apples are shredded and freeze dried, before feed pellets with the desired composition are prepared from the material. Three groups of rats are each provided one of the dietary treatments during 2.5 generation, and reproductive characteristics and performance are recorded. Subgroups of the last generation are selected for an intensive study in which uptake and excretion of energy and protein and selected micronutrients are determined. Respiration trials are performed to assess the energy metabolism, and simultaneous measurements of the activity levels of the rats are performed. In addition, blood and tissue samples of the rats will be obtained to study the effect of the dietary treatments on the immunological and antioxidant status of the rats. Data from the experiments are assembled and analysed using relevant statistical models, and the relationship to the nutritional characteristics of the plant material is described. Funding for the core project for a 4-year period is secured from the Danish Research Centre for Organic Farming (DARCOF). However, the intention is to provide a platform for international collaboration, since the well-documented material of plants and animals can provide multiple opportunities for associated projects. To investigate other aspects of plant composition or health than what is foreseen in the present project, or to follow up on it with additional experiments

Thermal coal drying with the high volatile matter output

Наведено аналіз сучасних технологій сушіння вугілля з високим вмістом летких. Промислове застосування набули парові сушарки з киплячим шаром продуктивністю 55 т/год, в яких теплоносієм є інертний азот, а необхідне тепло отримують за рахунок відхідних газів газифікатора, при цьому теплопередача здійснюється за допомогою гарячої води.Приведен анализ современных технологий сушки углей с высоким содержанием летучих. Промышленное применение получили паровые сушилки с кипящим слоем производительностью 55 т/ч, в которых теплоносителем служит инертный азот, а необходимое тепло получают за счет отходящих газов газификатора, при этом теплопередача осуществляется посредством горячей воды.An analysis of modern technologies of drying of coals with high content of volatile. Industrial applications received steam dryer with a fluidized bed with capacity of 55 tons/h, in which the coolant is inert nitrogen, and the necessary heat is generated by waste gases of the gasifier, the heat transfer is carried out by means of hot water