Deformation of Wood-Based Material During Supercritical Carbon Dioxide Treatment

The deformation of various wood-based materials during supercritical carbon dioxide treatment was assessed in situ at a range of pressurization and venting rates. Deformation was minimal with oriented strandboard (OSB), medium density fiberboard (MDF), and solid Douglas-fir heartwood, and even this slight deformation was rapidly recovered once the pressure was released. Higher degrees of deformation were observed in laminated veneer lumber (LVL) composed of Douglas-fir veneers and this deformation was not completely recovered at the end of the process. The resulting deformation resulted in permanent veneer separations. The results indicate that there is little risk of damage during supercritical carbon dioxide treatment of OSB, MDF, and Douglas-fir heartwood, but that further process studies will be required to identify treatment cycles suitable for treatment of LVL

Konjunktiv II-Variation im urbanen Sprachgebrauch in Österreich

The city as a social structure has a distinct relationship with its inhabitants. It creates a socio-pragmatic environment that produces communicative characteristics in the form of usage patterns that go hand in hand with conventionalised practices (cf. Gal 1987) and are dependent on everyday-life contextual aspects. Accordingly, research of urban varieties is ideally based on language data that is as authentic as possible and includes socio-demographic and diatopic aspects. Following this idea, the study presented examines the subjunctive II in urban Austria by analysing free conversations in formal and informal contexts (interviews and conversations among friends), and correlating the results with spatial and social parameters. The data used was collected in Vienna and Graz, the two largest cities in Austria, as well as in their respective surrounding areas and was grouped by gender, age and place of residence. The subjunctive II is realised in synthetic as well as periphrastic forms (cf. Merkle 1993: 69–73.; Donhauser 1992; Glauninger 2008). In rural Austria speakers use the entire range of variants (cf. Ziegler/Glantschnig 2013; Breuer/Wittibschlager 2020), while urban speakers exhibit a much narrower range, as we show in our analysis. Striking features in the use of variants can be seen above all in the form of contrasting modes of construction, i. e. synthetic vs. periphrastic realisation. The study reveals that there are hardly any differences between the two urban centres and only minor differences between a city and its surrounding area. However, the inclusion of social parameters provides a more differentiated picture: Here, higher relative frequencies of synthetic forms are found among male and older speakers compared to female and younger speakers. Thus, a preference for more conservative forms among the former contrasts with a preference for more modern (analytical) variants among the latter

Small-Scale Rack Testing of Wood-Frame Shear Walls

A series of racking tests were performed with small-scale (1.2-m X 1.2-m) plywood and OSB assemblies as a means of assessing the potential of reduced assembly sizes in screening variables for subsequent full-size tests. The plywood materials and configurations included variations in stud spacing, nailing, panel thickness and number, and addition of gypsum board. OSB assemblies differed in panel orientation and nailing. The framing used was KD Select Structural to minimize variations in fastening. Both of the standard assemblies (400-mm stud spacing) were also exposed to high relative humidity and effects of green framing. There were clear statistical differences between most plywood configurations, but the most prominent were for center-stud framing, and 9-mm-thick panels. The addition of gypsum board gave higher maximum load and greater stiffness, but the increased variability precluded finding significant differences with the basecase. OSB was significantly lower than plywood in most results. Moisture effects were minimal except for a greater deformation of OSB to the maximum load. The effect of green framing for the bottom plate was minimal

Internal Pressure Development and Deformation During Supercritical Fluid Impregnation of Selected Wood-Based Materials

The effect of supercritical carbon dioxide impregnation on pressure development was assessed on oriented strandboard (OSB), medium density fiberboard (MDF), laminated veneer lumber (LVL), and solid-sawn Douglas-fir heartwood lumber. Pressure differences between the surface and the interior were relatively small with MDF and OSB, owing to the presence of numerous pathways for fluid flow. Pressure differences tended to be higher in LVL and solid wood, but were still below the levels necessary for inducing material damage, except when flow directions were restricted and pressure was rapidly applied. The results indicate that supercritical fluid (SCF) impregnation is suitable for most composites, although care must be taken to limit pressure changes in situations where flow is restricted

"Sprachliche Mode(n)" in der Kommunikation unter österreichischen Jugendlichen

Sowohl unter VertreterInnen der Medien und der Sprachwissenschaft als auch unter sogenannten "SprachpflegerInnen" sind Sprachmoden ein durchaus frequentes - um nicht zu sagen "modernes" - Thema, wobei gerade Jugendliche und ihr Sprachgebrauch häufig zum Ausgangspunkt der Betrachtung gemacht werden: Lexikalische Auffälligkeiten und strukturelle Abweichungen im Sprachgebrauch der Jugendlichen zeigen starke Varianz und Fluktuation, die deutliche Indikatoren für sprachliche Modeerscheinungen sein können. Der folgende Beitrag soll Moden im Sprachgebrauch Jugendlicher in Österreich betrachten und der Frage nachgehen, ob diese nur kurzfristig bestehende Phänomene darstellen oder zu Sprachwandelprozessen führen können. Zu Beginn werden der Untersuchungsgegenstand "Jugend" näher betrachtet sowie wichtige Einflussfaktoren und Umstände in dessen Kontext angeführt. Anschließend sollen mögliche Sprachmoden in der Kommunikation unter Jugendlichen vorgestellt und erläutert werden. Die Ausführungen beziehen sich auf die im Projekt Jugendsprache(n) in Österreich erhobene Datengrundlage

Metadaten lexikalischer Ressourcen. Ausgewählte Herausforderungen bei der einheitlichen Beschreibung lexikalischer Ressourcen in Text+

<p>Posterpräsentation im Rahmen des 2. Text+ Plenarys: Connecting People and Data am 28./29. September an der SUB Göttingen.</p&gt

The crystal structure of D-threonine aldolase from Alcaligenes xylosoxidans provides insight into a metal ion assisted PLP-dependent mechanism.

Threonine aldolases catalyze the pyridoxal phosphate (PLP) dependent cleavage of threonine into glycine and acetaldehyde and play a major role in the degradation of this amino acid. In nature, L- as well as D-specific enzymes have been identified, but the exact physiological function of D-threonine aldolases (DTAs) is still largely unknown. Both types of enantio-complementary enzymes have a considerable potential in biocatalysis for the stereospecific synthesis of various β-hydroxy amino acids, which are valuable building blocks for the production of pharmaceuticals. While several structures of L-threonine aldolases (LTAs) have already been determined, no structure of a DTA is available to date. Here, we report on the determination of the crystal structure of the DTA from Alcaligenes xylosoxidans (AxDTA) at 1.5 Å resolution. Our results underline the close relationship of DTAs and alanine racemases and allow the identification of a metal binding site close to the PLP-cofactor in the active site of the enzyme which is consistent with the previous observation that divalent cations are essential for DTA activity. Modeling of AxDTA substrate complexes provides a rationale for this metal dependence and indicates that binding of the β-hydroxy group of the substrate to the metal ion very likely activates this group and facilitates its deprotonation by His193. An equivalent involvement of a metal ion has been implicated in the mechanism of a serine dehydratase, which harbors a metal ion binding site in the vicinity of the PLP cofactor at the same position as in DTA. The structure of AxDTA is completely different to available structures of LTAs. The enantio-complementarity of DTAs and LTAs can be explained by an approximate mirror symmetry of crucial active site residues relative to the PLP-cofactor

Reactions catalyzed by L- and D-threonine aldolases.

<p>Reactions catalyzed by L- and D-threonine aldolases.</p

Proposed catalytic mechanism of <i>Ax</i>DTA.

<p>Proposed catalytic mechanism of <i>Ax</i>DTA.</p