3,650 research outputs found
Success Strategies Being Implemented in Fresh Milk Supply Chains
Deregulation of the Australian dairy industry, and ensuing supermarket strategies are transforming the fresh milk supply chains. Factors such as increasing consumer awareness, concerns about food safety and environment, innovation, supply chain integration and rationalisation of supply base are adding momentum to this transformation. Milk processors in response to changing market expectations are getting proactive in their relationship with retailers across all aspects of business, innovating to generate sufficient returns from proprietary brands and strategically orienting themselves to develop a mixed customer portfolio and appropriate management structures to service that portfolio. Milk producers are expanding businesses to achieve production and cost efficiencies and strengthening contractual relationships on input and output side for a greater security.Livestock Production/Industries,
Single-cycle gap soliton in a subwavelength structure
We demonstrate that a single sub-cycle optical pulse can be generated when a
pulse with a few optical cycles penetrates through resonant two-level dense
media with a subwavelength structure. The single-cycle gap soliton phenomenon
in the full Maxwell-Bloch equations without the frame of slowly varying
envelope and rotating wave approximations is observed. Our study shows that the
subwavelength structure can be used to suppress the frequency shift caused by
intrapulse four-wave mixing in continuous media and supports the formation of
single-cycle gap solitons even in the case when the structure period breaks the
Bragg condition. This suggests a way toward shortening high-intensity laser
fields to few- and even single-cycle pulse durations.Comment: 4 pages, 6 figure
Phonon band structures of three-dimensional pentamode metamaterials
Three-dimensional pentamode metamaterials are artificial solids that
approximately behave like liquids, which have vanishing shear modulus.
Pentamodes have recently become experimental reality. Here, we calculate their
phonon band structures for various parameters. Consistent with static continuum
mechanics, we find that compression and shear waves exhibit phase velocities
that can realistically be different by more than one order of magnitude.
Interestingly, we also find frequency intervals with more than two octaves
bandwidth in which pure single-mode behavior is obtained. Herein, exclusively
compression waves exist due to a complete three-dimensional band gap for shear
waves and, hence, no coupling to shear modes is possible. Such single-mode
behavior might, e.g., be interesting for transformation-elastodynamics
architectures.Comment: 5 figure
Discovery of Multiple Modified F-430 Coenzymes in Methanogens and Anaerobic Methanotrophic Archaea Suggests Possible New Roles for F-430 in Nature
Methane is a potent greenhouse gas that is generated and consumed in anaerobic environments through the energy metabolism of methanogens and anaerobic methanotrophic archaea (ANME), respectively. Coenzyme F-430 is essential for methanogenesis, and a structural variant of F-430, 17(2)-methylthio-F-430 (F-430-2), is found in ANME and is presumably essential for the anaerobic oxidation of methane. Here we use liquid chromatography-high-resolution mass spectrometry to identify several new structural variants of F-430 in the cell extracts of selected methanogens and ANME. Methanocaldococcus jannaschii and Methanococcus maripaludis contain an F-430 variant (denoted F-430-3) that has an M+ of 1,009.2781. This mass increase of 103.9913 over that of F-430 corresponds to C3H4O2S and is consistent with the addition of a 3-mercaptopropionate moiety bound as a thioether followed by a cyclization. The UV absorbance spectrum of F-430-3 was different from that of F-430 and instead matched that of an F-430 derivative where the 17(3) keto moiety had been reduced. This is the first report of a modified F-430 in methanogens. In a search for F-430-2 and F-430-3 in other methanogens and ANME, we have identified a total of nine modified F-430 structures. One of these compounds may be an abiotic oxidative product of F-430, but the others represent naturally modified versions of F-430. This work indicates that F-430-related molecules have additional functions in nature and will inspire further research to determine the biochemical role(s) of these variants and the pathways involved in their biosynthesis
Trends In Australian Fresh Milk Supply Chains
The completion of the dairy industry deregulation process in June 2000 is transforming the fresh milk and fresh milk products supply chains in Australia. This transformation is set in an environment where markets are getting more complex and competitive, consumers more discerning and conscious about food safety and public policy is more focused on environment related issues. Supply chains are becoming more integrated, and innovation in product, process and supply chains is revolutionising the way products are being produced, distributed and marketed (Fearne & David 1999). This paper is based on research which, following supply chain management literature, identifies the success strategies in the dairy industry supply chains in Australia. The enquiry seeks to understand the nature and shape of supply chains and the exchange relationship between supply and value chains. The fieldwork for the research involved semi-structured interviews at middle to senior management level in the retail, processing, production and input market of the dairy industry supply chains. The data was managed and analysed using software NVivo ver. 2.0, which assists in identifying major themes and relationships between concepts in data
Numerical calculations of effective elastic properties of two cellular structures
Young's moduli of regular two-dimensional truss-like and eye-shape-like
structures are simulated by using the finite element method. The structures are
the idealizations of soft polymeric materials used in the electret
applications. In the simulations size of the representative smallest units are
varied, which changes the dimensions of the cell-walls in the structures. A
power-law expression with a quadratic as the exponential term is proposed for
the effective Young's moduli of the systems as a function of the solid volume
fraction. The data is divided into three regions with respect to the volume
fraction; low, intermediate and high concentrations. The parameters of the
proposed power-law expression in each region are later represented as a
function of the structural parameters, unit-cell dimensions. The presented
expression can be used to predict structure/property relationship in materials
with similar cellular structures. It is observed that the structures with
volume fractions of solid higher than 0.15 exhibit the importance of the
cell-wall thickness contribution in the elastic properties. The cell-wall
thickness is the most significant factor to predict the effective Young's
modulus of regular cellular structures at high volume fractions of solid. At
lower concentrations of solid, eye-like structure yields lower Young's modulus
than the truss-like structure with the similar anisotropy. Comparison of the
numerical results with those of experimental data of poly(propylene) show good
aggreement regarding the influence of cell-wall thickness on elastic properties
of thin cellular films.Comment: 7 figures and 2 table
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