MODULAR SIZE OF CLAY-PRODUCTS UNITS*

In cooperation with the Modular Service Association, studies have been made during the past two years on present unit masonry sizes as used in conventional building construction and their adaptability to a coordinated system. It was found that a significant relationship exists between present unit sizes in height, thickness, and length and a 4-in. modular dimension. There is little consistency, however, in the assembly of these units in similar or composite walls and far less in the coordination with component building materials and equipment. Recommendations are made for single masonry units based on whole multiples of four inches with consideration given to the various joint thicknesses. Methods are shown for relating unit sizes in fractional multiples of four inches plus mortar joints to the grid pattern. Suggestions for standardization of unit sizes are proposed to obtain maximum simplification and corresponding economy to meet postwar construction requirements.     

Intelligent speed adaptation as an assistive device for drivers with acquired brain injury: A single-case field experiment

Intelligent speed adaptation (ISA) was tested as an assistive device for drivers with an acquired brain injury (ABI). The study was part of the “Pay as You Speed” project (PAYS) and used the same equipment and technology as the main study (0030 and 0035). Two drivers with ABI were recruited as subjects and had ISA equipment installed in their private vehicle. Their speed was logged with ISA equipment for a total of 30 weeks of which 12 weeks were with an active ISA user interface (6 weeks = Baseline 1; 12 weeks = ISA period; 12 weeks = Baseline 2). The subjects participated in two semi-structured interviews concerning their strategies for driving with ABI and for driving with ISA. Furthermore, they gave consent to have data from their clinical journals and be a part of the study. The two subjects did not report any instances of being distracted or confused by ISA, and in general they described driving with ISA as relaxed. ISA reduced the percentage of the total distance that was driven with a speed above the speed limit (PDA), but the subjects relapsed to their previous PDA level in Baseline 2. This suggests that ISA is more suited as a permanent assistive device (i.e. cognitive prosthesis) than as a temporary training device. As ABI is associated with a multitude of cognitive deficits, we developed a conceptual framework, which focused on the cognitive parameters that have been shown to relate to speeding behaviour, namely “intention to speed” and “inattention to speeding”. The subjects’ combined status on the two independent parameters made up their “speeding profile”. A comparison of the speeding profiles and the speed logs indicated that ISA in the present study was more efficient in reducing inattention to speeding than affecting intention to speed. This finding suggests that ISA might be more suited for some neuropsychological profiles than for others, and that customisation of ISA for different neuropsychological profiles may be required. However, further studies with more subjects are needed in order to be conclusive on these issues.     

In vitro fermentation of 12 dietary fibres by faecal inoculum from pigs and humans

In vitro fermentation of 12 dietary fibres by faecal inocula from pigs and humans were performed. The fibres included homoglucans, mannans, fructans, polyuronides, and complex heteroglycans. Gas production, short chain fatty acid production and fibre degradation products were monitored during fermentation. Human inoculum has more ability to ferment resistant starch and fibres containing uronic acids. In contrast, pig inoculum is able to ferment cellulose, which is hardly fermented by human inoculum. The sugar and linkage composition of the fibres has an important influence on fibre fermentation patterns. Fibres containing uronic acids induced the production of acetate, whereas fibres containing neutral sugars induced the production of propionate or butyrate. Fermentation of the fructans showed that molecular size could be an influential factor, and fermentation of complex heteroglycans showed that the arrangement of sugars in the molecules may also affect the fermentation patterns. This experiment also shows that monitoring of fibre degradation products is important for understanding how fibres are degraded during fermentation.     

Biotemplated synthesis of Ag-ZnO nanoparticles/bacterial cellulose nanocomposites for photocatalysis application

ABSTRACT

Bacterial cellulose (BC) was used as a biotemplate for facile fabrication of silver-zinc oxide nanoparticles/bacteria cellulose (Ag-ZnO/BC) nanocomposite having high potential application in photocatalysis via a one-step method. Scanning electron microscopy images confirmed that BC nanofibers were uniformly coated with Ag-ZnO in aqueous suspension using co-precipitation method. The size of Ag-ZnO nanoparticle in BC and its photodegradability were increased with the increasing concentration of AgNO₃ added. The greatest efficiency is demonstrated by the ability of this material to degrade methylene blue (MB) by up to 76% after a 180 min ultraviolet irradiation period, indicated that the Ag-ZnO/BC nanocomposite is a promising candidate as robust ultraviolet responsive photocatalyst.     

Stereochemical and pharmacological differences between naturally occurring p-synephrine and synthetic p-synephrine

p-Synephrine, the primary protoalkaloid in Citrus aurantium (bitter orange) and some other Citrus species, exists in nature in the l- or [R-(?)]-enantiomeric form, whereas synthetic p-synephrine is a racemic mixture of the l- and d-enantiomeric forms. Based on receptor binding, the synthetic form is believed to exert approximately half the pharmacological activity of the naturally occurring protoalkaloid. This difference occurs because the d- or [S-(+)]-form provides little or no binding to adrenergic receptors in contrast to the l-form. Receptor binding studies also provide an explanation for the differences in pharmacological effects between the isomers p-synephrine and m-synephrine.