The influence of hydrogen bonding on mechanical anisotropy in oriented nylon-12

The anisotropy of dynamic tensile modulus in uniaxially and uniplanar-axially oriented nylon-12 sheets has been measured over the temperature range encompassing the α′-relaxation process. The influence of hydrogen bonding on the mechanical behaviour has been demonstrated by comparing these anisotropy measurements for specimens which have been subjected to different thermal treatments.     

Toward a unified approach for thermal nonequilibrium in gas-liquid systems

A unified viewpoint is described which can be utilized to determine nonequilibrium liquid-vapor phase change in both post-dryout and decompressive flashing systems. It is shown that nonequilibrium phase exchange is in general a first order relaxation process and, as such, is a path dependent initial value problem rather than a local phenomenon. In all cases three quantities must be adequately specified: the initial value or inception criteria, the interfacial area density and the interfacial heat transfer rates.     

Effect of pre rigor stretching on beef tenderness development

The objective of this study was to determine effects of pre rigor stretching on beef tenderness development. Beef loins (M. longissimus dorsi; n=24) were assigned to either stretching or non-stretching treatments and aged for 14days at -1.5°C. Sarcomere length, shear force, water-holding capacity and proteolysis were determined for the loins at 1, 7 and 14days of ageing. Stretching increased the length of the loins by 33% resulting in a trend of increasing sarcomere length (P=0.19). However, no significant differences for shear force values, purge, drip and cooking losses between treatments were found. Shear force values decreased with ageing times (P<0.05). Western blot assay found that stretching did not affect the extent of desmin degradation. The findings from the present study suggest that pre rigor stretching with the current increase in length will not contribute to tenderness improvement of the beef loins.     

Binding of an arm repeat protein to the kinase domain of the S-locus receptor kinase

Screening of a yeast two-hybrid library for proteins that interact with the kinase domain of an S-locus receptor kinase (SRK) resulted in the isolation of a plant protein called ARC1 (Arm Repeat Containing). This interaction was mediated by the C-terminal region of ARC1 in which five arm repeat units were identified. Using the yeast two-hybrid system and in vitro binding assays, ARC1 was found to interact specifically with the kinase domains from SRK-910 and SRK-A14 but failed to interact with kinase domains from two different Arabidopsis receptor-like kinases. In addition, treatment with a protein phosphatase or the use of a kinase-inactive mutant reduced or abolished the binding of ARC1 to the SRK-910 kinase domain, indicating that the interaction was phosphorylation dependent. Lastly, RNA blot analysis revealed that the expression of ARC1 is restricted to the stigma, the site of the self-incompatibility response.