38 research outputs found
Bartter- and Gitelman-like syndromes: salt-losing tubulopathies with loop or DCT defects
Salt-losing tubulopathies with secondary hyperaldosteronism (SLT) comprise a set of well-defined inherited tubular disorders. Two segments along the distal nephron are primarily involved in the pathogenesis of SLTs: the thick ascending limb of Henle’s loop, and the distal convoluted tubule (DCT). The functions of these pre- and postmacula densa segments are quite distinct, and this has a major impact on the clinical presentation of loop and DCT disorders – the Bartter- and Gitelman-like syndromes. Defects in the water-impermeable thick ascending limb, with its greater salt reabsorption capacity, lead to major salt and water losses similar to the effect of loop diuretics. In contrast, defects in the DCT, with its minor capacity of salt reabsorption and its crucial role in fine-tuning of urinary calcium and magnesium excretion, provoke more chronic solute imbalances similar to the effects of chronic treatment with thiazides. The most severe disorder is a combination of a loop and DCT disorder similar to the enhanced diuretic effect of a co-medication of loop diuretics with thiazides. Besides salt and water supplementation, prostaglandin E2-synthase inhibition is the most effective therapeutic option in polyuric loop disorders (e.g., pure furosemide and mixed furosemide–amiloride type), especially in preterm infants with severe volume depletion. In DCT disorders (e.g., pure thiazide and mixed thiazide–furosemide type), renin–angiotensin–aldosterone system (RAAS) blockers might be indicated after salt, potassium, and magnesium supplementation are deemed insufficient. It appears that in most patients with SLT, a combination of solute supplementation with some drug treatment (e.g., indomethacin) is needed for a lifetime
Biodiversität am Piz Alv (2974 m): Lokaler hot spot in der Region Bernina (Graubünden, Schweiz)
During the years 2002, 2003 and 2006, vegetation records, 201 in total covering 30 plant communities with a total of 415 vascular plants, were kept about an area of 0.32 km2 at the foot of the Piz Alv (2974 m a.s.l., Bernina pass, Canton of the Grisons, Switzerland). The records have been investigated regarding biodiversity (Shannon-index and evenness) and the constancy of occurrence. In addition an earlier vegetation map of Piz Alv has been revised
and completed. On the lower mountain slope the dominating features are acidophilic subalpine meadows (Geo montani-Nardetum), slope peat bogs and pastures, whereas on the upper slope section, basophilic alpine meadows (Seslerio-Caricetum sempervirentis) and pioneer plant communities (Dryadetum octopetalae) prevail.
The highest biodiversity is shown by the plant communities Geo montani-Nardetum and Seslerio-Caricetum sempervirentis with 179 and 152 plant species respectively (Shannonindex
2.80 and 2.37 respectively). The highest constancy of plant species occurrence is exhibited by the basophilic alpine meadows (Seslerio-Caricetum sempervirentis), subalpine pastures (Poion alpinae), hanging bogs and alluvions. 10 species of orchids could be recorded and more than 12 additional rare plant species, found in the Swiss Red Data Book, could be recognized. The investigated locality in the Bernina pass area represents a local Swiss hot spot of plant biodiversity and should be put under nature protection
Piz Alv (2974 m) – hot spot der Biodiversität am Berninapass
Am Fuss des Piz Alv (2974 m) wurden auf einer Fläche von 0.32 km2 in den Jahren 2002, 2003 und 2006 insgesamt 201 Pflanzenbestände (30 Pflanzengesellschaften, 415 Blüten- und Farnpflanzenarten) erfasst und hinsichtlich der Biodiversität statistisch ausgewertet. Zudem wurde eine auf einer früheren Kartierung beruhende Vegetationskarte neu erstellt.
Im von saurem Silikatgestein dominierten unteren Hangabschnitt sind Borstgras-Rasen im Mosaik mit Hangmooren und Weiden verbreitet. Die Nutzung als Alpweide hat zu lokal gedüngten Stellen geführt, die wesentlich artenärmer sind. Im oberen Hangbereich herrschen basiphile Blaugras-Halden und auf beweglichem Karbonatschutt Silberwurz- Pioniervegetation vor. Mit 179 Pflanzenarten ist der Borstgras-Rasen die artenreichste Gesellschaft, gefolgt vom Blaugras-Rasen mit 152 Arten (Shannon-Indices 2.80 bzw. 2.37). Die höchsten Stetigkeits-Werte weisen Arten aus den
Blaugras-Rasen und den Hangmooren auf. Es konnten 10 Orchideen-Arten nachgewiesen werden, wobei zwei Arten als selten gelten. Rund 12 selten am Piz Alv vorkommende Arten gehören zur Roten Liste der Schweizer Flora. Im gesamtschweizerischen Vergleich stellt die Vegetation am Piz Alv einen hot spot der regionalen Biodiversität dar, welcher geschützt werden müsste
Environmentally Benign Formation of Nickel Hexacyanoferrate-Derived Mesoframes for Heterogeneous Catalysis
The tetramethylammonium hydroxide (TMAH)-controlled alkaline etching of nickel hexacyanoferrate (NiHCF) mesocrystals is explored. The alkaline etching enables the formation of hollow framework structures with an increased surface area, the exposure of active Ni and Fe sites and the retention of morphology. The ambient reaction conditions enable the establishment of a sustainable production. Our work reveals novel perspectives on the eco-friendly synthesis of hollow and colloidal superstructures for the efficient degradation of the organic contaminants rhodamine-B and bisphenol-A. In the case of peroxomonosulfate (PMS)-mediated bisphenol-A degradation, the rate constant of the etched mesoframes was 10,000 times higher indicating their significant catalytic activity.publishe
Environmentally Benign Formation of Nickel Hexacyanoferrate-Derived Mesoframes for Heterogeneous Catalysis
The tetramethylammonium hydroxide (TMAH)-controlled alkaline etching of nickel hexacyanoferrate (NiHCF) mesocrystals is explored. The alkaline etching enables the formation of hollow framework structures with an increased surface area, the exposure of active Ni and Fe sites and the retention of morphology. The ambient reaction conditions enable the establishment of a sustainable production. Our work reveals novel perspectives on the eco-friendly synthesis of hollow and colloidal superstructures for the efficient degradation of the organic contaminants rhodamine-B and bisphenol-A. In the case of peroxomonosulfate (PMS)-mediated bisphenol-A degradation, the rate constant of the etched mesoframes was 10,000 times higher indicating their significant catalytic activity
Proyecto ARES - A ccesso a la red de estaciones solares
El objetivo del Proyecto ARES (Acceso a la Red de Estaciones Solares) es facilitar el acceso a datos registrados en esaciones de medida de la radiación solar, a través de la definición y puesta a punto de una plataforma para la incorporación y el acceso estandarizado a la información. AsÃ, entre los objetivos, se incluyen la homogeneizacion de los precedimientos de: adquisición de datos, control de calidad, almacenamiento y tratamiento. Aunque se pretende desarrollar una herramienta que pueda extenderse a estaciones emejantes por configuración o variables medidas, el lanzamiento de la iniciativa se enmarca en el contexto de la colaboración enre distintas Divisiones del CIEMAT con el Departamento de Qualification del "Institute of Solar Research" del DLR (Deutsches Zentrum für Luft- und Raumfahrt). En esta primera etapa, se unificarán criterios en el contexto de las estaiones ubicadas en la PS