The influence of high temperatures on calibration of non-destructive testing of concrete

The intention of this experimental work is to investigate the influence of elevated temperatures of short duration (usually during fires in buildings) on the properties of concrete that affect the measurements by non-destructive methods (rebound hammer and pulse velocity). Relationships between strength of concrete as well as rebound and pulse velocity versus heating temperatures are established. Finally, the above results are evaluated to find the direct relation between non-destructive measurements and strength of concrete exposed to fire.     

Zur bors?urefreien Haltbarmachung von frischen Speisegarnelen und Garnelenfleisch II. Mitteilung

Zusammenfassung Im Hinblick auf das zu erwartende Verbot der bisher zur Konservierung von Speisegarnelen benutzten Borsäure wurden Koch- und Konservierungsversuche mit unbedenklichen Konservierungsmitteln durchgeführt, deren Ergebnisse erkennen lassen, daß im Gegensatz zur Wirkungsweise der Borsäure die untersuchten unbedenklichen Konservierungsmittel nur dann eine ausreichende Wirkung entfalten, wenn sie den Garnelen unmittelbar nach der Kochung zugesetzt werden, wie es nach den z.Z. gültigen Bestimmungen nur bei einer Landkochung geschehen kann.Es wurden deshalb Transportversuche mit lebenden Garnelen angeschlossen, die zeigten, daß die in den kühleren Frühjahrs- und Herbstmonaten gefangenen Garnelen einen 8stündigen Transport ohne besondere Vorkehrungen an Bord der Fangfahrzeuge praktisch verlustfrei lebend überstehen, daß dagegen die in den Sommermonaten aus wärmerem Wasser gefangenen Garnelen schon so ermattet an Bord kommen, daß sie auch beim Transport in einem Kühlbehälter bei 5° C nicht mit Sicherheit zu 100% bis zur Anlandung am Leben gehalten werden können.Weitere Maßnahmen zur borsäurefreien Konservierung und zur Lebenderhaltung der Garnelen während des Transports, die in Versuchen geprüft werden sollen, werden erörtert.     

Dynamic stability of periodic solutions of large scale nonlinear systems

A method suitable for the stability analysis of periodic solutions of large nonlinear systems is presented. The stability behaviour is inferred from a Galerkin approximation of the associated Poincaré map. The practical value of the method is shown by applying it to the nonlinear finite element model of a large scale wind energy convertor.     

Nerve growth factor and proprotein convertases furin and PC7 in transected sciatic nerves and in nerve segments cultured in conditioned media: their presence in Schwann cells, macrophages, and smooth muscle cells

Synthesis of proteins such as nerve growth factor (NGF) is induced after nerve lesion. The NGF precursor (pro-NGF) requires a posttranslational processing by proprotein convertases to become active. In this report, we re-examine the localization of NGF protein and mRNA in injured nerve and show that the candidate pro-NGF convertases furin and PC 7 colocalize with NGF in non-neuronal cells in nerve. By Northern blot analysis, 1.5-kb and 1.3-kb NGF mRNAs were shown to be increased in distal and immediately proximal nerve segments on days 1, 4, and 14 after lesion; by Western blot analysis, NGF proteins of high molecular weight were detected after injury. In vivo, two phases of NGF immunopositivity were observed, in macrophages and perivascular cells shortly after lesion and in endoneurial cells on day 1 and 4. To identify the cells containing NGF, nerve segments were incubated in serum-containing medium with or without conditioning by white blood cells isolated from the circulation. Both hybridization and immunoreactivity signals for NGF were elevated after incubation of nerve segments for 4 hours in conditioned media, so that cells with NGF immunoreactivity could be identified by antibodies to specific cell markers. In these nerve fragments, Schwann cells, perivascular smooth muscle cells, and macrophages contained NGF immunoreactivity. The concentration of furin and PC7 mRNA also increased in lesioned nerves. By immunocytochemical investigation of nerve explants, furin and PC7 were detected in endoneurial cells, macrophages and perivascular cells and were colocalized with NGF. These in vitro and in vivo findings suggest that both furin and PC7 are associated with NGF in several cell types of the sciatic nerve and, hence, may be implicated in intracellular processing of pro-NGF.     

Verwendbarkeit der Reduktaseprobe zur Beurteilung der hygienischen Beschaffenheit der Milch

Ohne ZusammenfassungMitteilung aus dem bakteriologischen Laboratorium der Zentralanstalt für landwirtschaftliches Versuchswesen auf Experimentalfältet bei Stockholm.     

A GC–MS-based metabonomic investigation of blood serum from irritable bowel syndrome patients undergoing intervention with acidified milk products

In the present study, the use of gas chromatography mass spectrometry (GC–MS)-based metabonomics to characterize blood serum in an intervention study of patients suffering from the common gastrointestinal disorder irritable bowel syndrome (IBS) was investigated. The patients included in the study consumed an acidified milk product with (n = 30) or without probiotics (n = 31) (Lactobacillus paracasei F19, Lactobacillus acidophilus LA-5 and Bifidobacterium lactis BB-12) for an 8-week period, and blood serum samples were collected before and after the intervention. Acidified milk is commonly used as a delivering vector for probiotics in commercial consumer settings. The serum samples were extracted and derivatized using N-Methyl-N-(trimethylsilyl) trifluoroacetamide (MSTFA), and GC–MS analysis was carried out. Multivariate data analysis including principal component analysis (PCA), orthogonal partial least squares-discriminant analysis (OPLS-DA), and S-plot was applied on the obtained GC–MS data, which revealed higher serum lactate, glutamine, proline creatinine/creatine, and aspartic acid levels and lower serum glucose levels after the intervention period for both treatment groups. Consequently, the present study indicated an effect of acidified milk consumption on the plasma metabolite profile, which was independent of a concomitant intake of probiotics. In addition, the present study demonstrates that GC–MS is a useful analytical technique for metabonomics studies of blood serum.     

Zur Kenntnis des Weizenklebers

Ohne ZusammenfassungVorläufige Mitteilung aus der Untersuchunganstalt Erlangen.