RESUMEN
The design of free-spanning pipelines is performed with the aim of ensuring their integrity against permanent loads generated by seabed roughness, functional loads induced by internal pressure and temperature, and dynamic loads induced by marine currents and direct wave action. In particular, a load and resistance factored design is applied that focuses on extreme environmental loads, and a fatigue limit state approach is applied as a consequence of free-span dynamics due to vortex shedding-induced vibration and direct wave action. The pipeline free-span scenario can be permanent, when generated by seabed roughness, or characterized by short- to long-term evolution, when generated by seabed mobility and scouring in shallow waters. Free-span analysis is generally a task involving a number of disciplines and should be carried out using a multidisciplinary approach. The paper illustrates various themes related to free-span analysis: (i) free-span scenarios, (ii) characterization of the environment from deep to shallow water related to proper seabed properties, (iii) hydrodynamic load regimes, (iv) pipeline free-span design assessment aiming to reduce overstress and fatigue damage, (v) erodible seabed mobility and local scour, and (vi) some experiences of inspection surveys chosen as representative of a free-spanning pipeline in sandy soils.
RESUMEN
Ion chromatography and colorimetry were used to determine nitrate ion concentration in 76 different pork meat products (salami, mortadella, wurstel, raw and cooked ham and other whole-muscle cooked products) and the results were compared. The comparison revealed that the two techniques yield quantitatively similar results, except in cases where the matrix was so complex that it might have influenced the analytical data. These results are consistent with those obtained by other authors who used UV spectrophotometric detection.
Asunto(s)
Productos de la Carne/análisis , Nitratos/análisis , Animales , Cromatografía por Intercambio Iónico/métodos , Culinaria , Análisis de Regresión , Espectrofotometría Ultravioleta/métodos , PorcinosRESUMEN
The authors examine a series of 20 patients suffering from AOCP (?) at Fontaine's 2nd stage treated with calciparine s.c. in a single daily dose of 12500 IU for three months. The parameters of clinical assessment of claudicatio intermittens show statistically significant increases of ILR and ILA which were not correlated to marked variations of the Windsor index. The extremely positive results in terms of the clinical trend of the disease are encouraging with a view to a more extensive application of this therapeutic approach in peripheral arterial disease of the lower limbs.
Asunto(s)
Fibrinolíticos/uso terapéutico , Heparina/uso terapéutico , Claudicación Intermitente/tratamiento farmacológico , Pierna/irrigación sanguínea , Enfermedades Vasculares Periféricas/tratamiento farmacológico , Anciano , Evaluación de Medicamentos , Femenino , Heparina/farmacología , Humanos , Masculino , Persona de Mediana Edad , Factores de TiempoRESUMEN
Hypercholesterolemia can be a risk factor which engenders coronary heart disease. Today, it seems certain that lowering the cholesterolemia reduces this risk, especially if this reduction is referred to the cholesterol which is linked to the low density lipoprotein, called LDL. It has been demonstrated that the principle way to remove the LDL is by getting it into the hepatocyte through a specific membrane receptor, the research, therefore, has been developed with the aim of pharmacologically modifying the quota of intercellular cholesterol and consequently, in the modulation of the receptivity function by the interference of the LDL uptake, assisting a faster clearance. We can identify a new class of pharmacological drugs, that are the specific inhibitors of the HMGCoA reductase, fundamental enzime in the biosynthesis of cholesterol. This group of inhibitors has recently been enriched by the addition of a new molecule pravastatin. Our task has been to confirm the effectiveness and tolerability of pravastatin, administered for a prolonged period to patients with high levels of cholesterolemia; we have compared it with gemfibrozil, a well-known medicine which has hypocholesterolemic effects. In conclusion, our work, whilst emphasising the expediency of ipolipidic treatment, has undoubtedly proved, that 40 mg of pravastatin in a single evening dose, shows a high degree of efficiency, without side effects. Due to these factors, we can also say that pravastatin prevents, or really induces the regression, of atheroscherotic disease.