A coarse-grained simulation model for a third generation liquid crystalline dendrimer (LCDr) is presented. It allows, for the first time, for a successful molecular simulation study of a relation between the shape of a polyphilic macromolecular mesogen and the symmetry of a macroscopic phase. The model dendrimer consists of a soft central sphere and 32 grafted chains each terminated by a mesogen group. The mesogenic pair interactions are modelled by the recently proposed soft core spherocylinder model of Lintuvuori and Wilson [J. Chem. Phys, 128, 044906, (2008)]. Coarse-grained (CG) molecular dynamics (MD) simulations are performed on a melt of 100 molecules in the anisotropic-isobaric ensemble. The model LCDr shows conformational bistability, with both rod-like and disc-like conformations stable at lower temperatures. Each conformation can be induced by an external aligning field of appropriate symmetry that acts on the mesogens (uniaxial for rod-like and planar for disc-like), leading to formation of a monodomain smectic A (Sm A ) or a columnar (Col) phase, respectively. Both phases are stable for approximately the same temperature range and both exhibit a sharp transition to an isotropic cubic-like phase upon heating. We observe a very strong coupling between the conformation of the LCDr and the symmetry of a bulk phase, as suggested previously by theory. The study reveals rich potential in terms of the application of this form of CG modelling to the study of molecular self-assembly of liquid crystalline macromolecules.

Recommended field application rates of herbicides have to give effective weed control in every situation and are, thus, often higher than that required for specific fields. An understanding of the interaction between crop:weed competition and herbicide dose may, in many cases, allow herbicide application rates to be reduced, important both environmentally and economically. We have developed a model of the interaction between crop:weed competition and herbicide dose, using an empirical model of the relationship between crop yield and weed biomass (related to weed density), and an empirical model of the relationship between weed biomass and herbicide dose. The combined model predicts crop yield, given herbicide dose and weed biomass at an interim assessment date. These crop yield loss predictions may be used to quantify the herbicide dose required to restrict yield loss to a given percentage. Parameters of the model were estimated and the model tested, using results from experiments, which used cultivated oats (Avena sativa) or oilseed rape (Brassica napus) as model weeds in a crop of winter wheat (Triticum aestivum).For the crop:weed:herbicide combinations investigated there was little increase in crop yield for herbicide dose rates above 20% of recommended field rates, in broad agreement with the model predictions. There may still be potential for further reduction below this level on economic grounds; the model could be used to estimate the `break‐even' herbicide dose.

Modified atmosphere packaging (MAP) technology has been commercially viable since the 1970s. Currently, MAP is extensively used worldwide to preserve the quality and extend the shelf-life of whole fresh fruits and vegetables, but is also increasingly used to extend the shelf-life of minimally processed fresh fruit and vegetables. This review discusses new processes and technologies that can be used to improve quality preservation and consumer acceptability of minimally processed produce where high respiration rates and challenging degradation processes operate. New packaging innovations are enabling producers and retailers to further maintain quality for longer. Innovative approaches to extend shelf-life include active MAP with differentially permeable films, films that incorporate antimicrobial properties, edible coatings that confer barriers properties, and the use of non-traditional gases to modify respiration. Intelligent packaging using integrated sensor technologies that can indicate maturity, ripeness, respiration rate and spoilage are also appearing. This review demonstrates that preservation technologies and associated packaging developments that can be combined with modified atmosphere are constantly evolving technology platforms. Adoption of combinations of technology improvements will be critical in responding to commercial trends towards more minimally processed fresh-cut and ready-to-eat fruit and vegetable products, which require specialized packaging solutions.

Recent advances in postharvest technologies to extend the shelf life of blueberries (Vaccinium sp.), raspberries (Rubus idaeus L.) and blackberries (Rubus sp.

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Transition metal catalysts were incorporated into polymers which formed the surface for bacterial attachment and biofilm formation in a constant depth film fermenter (100 microns thickness), flow chamber (about 30 microns thickness) and in batch culture (< 30 microns thickness). The catalysts drive the breakdown of persulphates to reactive oxygen species. When Pseudomonas aeruginosa biofilms were exposed to dilute solutions of potassium monopersulphate (20 micrograms ml-1-1 mg ml-1), significant enhancement of killing was notable for catalyst-containing surfaces over that of controls. The degree of enhancement was greatest for thin films, but was nevertheless significant for the 100 microns thick biofilms. Fluorescence probes and viability staining, in conjunction with laser confocal microscopy, showed that reactive species were generated at the biofilm-substratum interface and killed the biofilm from the inside. Reaction-diffusion limitation now concentrates the active species within the biofilm rather than protecting it, and a diffusion bump is established whereby further treatment agent is drawn to the substratum enabling relatively thick biofilms to be disinfected.

Whollydooleya tomnpatrichorum gen. et sp. nov. is a new, highly specialised hypercarnivorous dasyuromorphian from a new mid-Cenozoic limestone deposit southwest of the Riversleigh World Heritage Area in northwestern Queensland. Dental dimensions suggest it may have weighed at least twice as much as the living Tasmanian devil (Sarcophilus harrisii). Although known only from a lower molar, it exhibits a plethora of carnivorous adaptations including a hypertrophied protoconid, tiny metaconid and a battery of vertical carnassial blades between most of the major cusps, most of which incorporate carnassial notches to immobilise materials being sheared. It is unique among dasyuromorphians in having a massive entoconid that closes the entire lingual side of the talonid. Comparison with previously known thylacinid and dasyurid hypercarnivores suggests its relationships are closer to dasyurids than thylacinids in the main because of the very large entoconid, a cusp that is relatively small to absent in all known thylacinids but commonly small to large in dasyurids. However, the extent of enlargement of the entoconid suggests that it is not closely related to previously known Cenozoic hypercarnivorous dasyurids in the genera Dasyurus, Glaucodon, Sarcophilus or any of the other previously described Cenozoic dasyurids. Although the early late Miocene Ganbulanyi djadjinguli is only known from an upper molar, the reduced area of its protocone suggests a correspondingly reduced rather than hypertrophied entoconid in its as-yet-unknown lower molars. Reconsideration of the structure of the talonid in species of Sarcophilus even suggests that within that Quaternary lineage, the entoconid may have been entirely lost, with the posteriorly displaced metaconid taking its functional place as an occlusal counterpart for the blades of the protocone. The large size of the new species signals the earliest indication within the dasyurid radiation of a late Cenozoic trend towards gigantism that became evident in many lineages of Australian marsupials. While the age is uncertain, on the basis of associated taxa such as species of Ekaltadeta, it is probably either mid or late Miocene in age. Geological features of the deposit suggest it was formed within a pool in a cave environment that periodically underwent desiccation. Some grains suggest an aeolian as well as an alluvial and pluvial origin for the deposit. This may relate to current understanding about environmental change that took place in the region following the mid Miocene climate oscillation.

Seeds of mahoe exude a brown watersoluble substance over a number of days. The properties of this exudate were examined. Mahoe seed did not germinate until all exudate was removed. Extracts ofexudate inhibited germination ofleached mahoe seed and five of six other species tested. Replacement ofthe exudate with fresh water restored germination in mahoe and in all but one test species. It is concluded that the exudate acts mainly as an autoinhibitorand has littIeallelopathic role. It confers an advantage on mahoe seedling establishment by allowing germination only after long periods of rain.