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Bei der Herstellung kreiszylindrischer ringversteifter Tankbehälter aus Stahl mit abgestufter Wanddicke und rippenversteiftem Kuppeldach treten kritische Montagephasen an der oben offenen Schale unter Windbeanspruchung auf. Der normative Nachweis nach DIN 18800‐4 auf Basis vereinfachender Berechnungsansätze ist in einigen Fällen nicht erfüllbar. Das europäische Regelwerk gestattet Abminderungen der charakteristischen Werte der Windgeschwindigkeit in Abhängigkeit von der Dauer des Bauzustandes und der Möglichkeit zur Ergreifung präventiver Sicherungsmaßnahmen. An einem Behälter werden unter Ansatz realistischer Verteilungen der Windlast über den Zylinderumfang und geometrischer Ersatzimperfektionen auf numerischem Weg reale Beulwiderstände für einzelne Herstellungsabschnitte bestimmt. Die Anwendung probabilistischer Überlegungen auf die Ergebnisse des mechanischen Modells ermöglicht detailliertere Sicherheitsaussagen in bezug auf die Dauer der temporären Zustände.

In cartilage, link protein(s) (LP) stabilize proteoglycan aggregates via their specific association with hyaluronic acid and proteoglycan monomers. Two major link glycoproteins are produced in bovine articular cartilage, designated LP1 (49.5 kDa) and LP2 (44.0 kDa), whereas rat chondrosarcoma produces a single link protein species similar in size to bovine LP2. Although multiple link proteins differ to a significant degree in carbohydrate content, it is not known whether they arise from variable glycosylation of a single common protein core or from complete glycosylation of different protein cores. Biosynthesis of these molecules has been studied under conditions where differences generated by N-linked glycosylation would not be evident. Link proteins were immunoprecipitated 1) from cell-free translation products of total cellular and size fractionated RNA and 2) from cell lysates and medium of cultured chondrocytes using short term radioactive labeling of the protein in the presence and absence of tunicamycin. A 42-kDa link protein precursor is synthesized by cell-free translation of either rat chondrosarcoma or bovine chondrocyte mRNa. An apparently single 41.5-kDa link protein is synthesized with inhibition of N-linked glycosylation by tunicamycin, whereas LP1 and LP2 are the mature products of cultured bovine chondrocytes. The size range of translatable rat chondrosarcoma LP mRNA is 4.0-5.5 kilobase pairs and bovine LP mRNA is 3.0-4.5 kilobase pairs, both much larger than required to encode the link protein molecule. These results suggest that a single link protein precursor gives rise to multiple fully glycosylated forms and that link protein is not synthesized as a significantly larger “pro” form.

Summary An apparatus for serial washing of soil particles is described. When forest humus was washed 50 times in an illustrative experiment, the proportion of dark and slow-growing mycelia among fungal isolates was increased from 5 to over 50 per cent.

The fungi decomposing broadleaved litter could be grouped into at least three distinct associations: those colonising leaves on the tree; those colonising newly fallen litter, and those colonising older litter from the soil. An overall estimate of the importance of a given species could be obtained by combining data on abundance, duration of activity, and decomposing ability of sterile litter. The flora of higher fungi in high-altitude oak woodlands was shown to have significant differences from that at low altitudes.

Majesticpotatoes planted in soil naturally infested withStreptomyces scabieswere trickle irrigated to prevent infection of the tubers except during consecutive 7-day periods in the first eight weeks when tubers were developing (28 May to 23 July).

THE leaf-clearing method described here was designed to observe fungal hyphæ on oak leaves from litter, and to differentiate hyphæ inside the leaf from those on the surface.

No abstract.