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The environmental issues of petroleum-derived polymeric foams have necessitated seeking renewable alternatives. This work aims to prepare renewable free-radically polymerized polymeric foams with the ability to biodegrade. Furthermore, this work attempted to incorporate a bio-based reactive diluent, which has not been reported in the literature. The synthesis of maleated castor oil glycerides was performed with products analyzed by Fourier transform infrared spectrometry using attenuated total reflection (ATR-FTIR) and 1 H nuclear magnetic resonance ( 1 H NMR) spectroscopy. Polymeric foams were prepared using maleated castor oil glycerides via free radical copolymerization with styrene and isobornyl methacrylate as reactive diluents. Scanning electron microscopy (SEM) was used to determine anisotropic macrocellular morphology, with log-normal cell diameter distributions. The compressive mechanical and energy absorption properties were investigated; the polymeric foams displayed Young's modulus up to 26.85 ± 1.07 MPa and strength up to 1.11 ± 0.021 MPa using styrene as the reactive diluent, and Young's modulus up to 1.38 ± 0.055 MPa and strength up to 0.088 MPa when incorporating isobornyl methacrylate. Furthermore, a thorough analysis of the cellular structure-property relationships was performed, indicating relationships to cell diameter, cell wall thickness and apparent density. The polymeric foams displayed rapid mass loss in an aerobic soil environment with multiple erosion sites revealed by SEM. In conclusion, renewable polymeric foams with excellent compressive properties were achieved using styrene as reactive diluent, but the incorporation of isobornyl methacrylate decreased strength-related properties.

During reproduction in flowering plants, the male gametophyte delivers an immotile male gamete to the female gametophyte in the pistil by formation of pollen tubes. In Arabidopsis thaliana, two synergid cells situated on either side of the egg cell produce cysteine-rich chemoattractant peptide LURE that guides the pollen tube to the female gametophyte for sexual reproduction. Recently, in Arabidopsis thaliana, Pollen Receptor Kinase 3 (PRK3), along with PRK1, PRK6, and PRK8, have been predicted to be the receptors responsible for sensing LURE. These receptors belong to the Leucine Rich Repeat Receptor Like Kinases (LRR-RLKs), the largest family of receptor kinases found in Arabidopsis thaliana. How PRKs regulate the growth and development of the pollen tube remains elusive. In order to better understand the PRK-mediated signaling mechanism in pollen tube growth and guidance, we have determined the crystal structure of the extracellular domain (ecd) of PRK3 at 2.5 Å, which resembles the SERK family of plant co-receptors. The structure of ecdPRK3 is composed of a conserved surface that coincides with the conserved receptor-binding surface of the SERK family of co-receptors. Our structural analyses of PRK3 have provided a template for future functional studies of the PRK family of LRR-RLK receptors in the regulation of pollen tube development.

In seeking approval from the US Food and Drug Administration (FDA) for clinical trial evaluation of an experimental medical device, a sponsor is required to submit experimental findings and support documentation to demonstrate device safety and efficacy that are in compliance with Good Laboratory Practices (GLP). The objective of this project was to develop an integrated data acquisition (DAQ) system and documentation strategy for monitoring and recording physiological data when testing medical devices in accordance with GLP guidelines mandated by the FDA. Data aquisition systems were developed as stand-alone instrumentation racks containing transducer amplifiers and signal processors, analog-to-digital converters for data storage, visual display and graphical user-interfaces, power conditioners, and test measurement devices. Engineering standard operating procedures (SOP) were developed to provide a written step-by-step process for calibrating, validating, and certifying each individual instrumentation unit and the integrated DAQ system. Engineering staff received GLP and SOP training and then completed the calibration, validation, and certification process for the individual instrumentation components and integrated DAQ system. Eight integrated DAQ systems have been successfully developed that were inspected by regulatory affairs consultants and determined to meet GLP guidelines. Two of these DAQ systems were used to support 40 of the pre-clinical animal studies evaluating the AbiCor artificial heart (ABIOMED, Danvers, MA). Based in part on these pre-clinical animal data, the AbioCor clinical trials began in July 2001. The process of developing integrated DAQ systems, SOP, and the validation and certification methods used to ensure GLP compliance are presented in this article.

Child's Pad is a gravel construction pad that was contaminated with petroleum during oil-field service operations in Deadhorse, AK. As part of a remedial action plan, a buffer strip of uncontaminated sandy gravel was placed along certain sections of the pad boundary. A peroxygen formulation manufactured by Regenesis Copyright, sold as Oxygen Release Compound (ORC(R)), was placed in the buffer strips. The ORC was intended to supply oxygen to aerobic microorganisms capable of degrading petroleum. Tests were conducted in a 1/2 scale laboratory cell to determine the oxygen release characteristics of the ORC when subjected to expected subsurface flow rates of up to 0. 02 l/s (6.9 m/day). In laboratory tests, a zone of enhanced oxygen concentration was formed down-gradient from the ORC socks. Only during periods when the flow rate was less than 0.01-0.015 l/s (3. 5-5.2 m/day) was ORC-oxygen observed at monitoring points up-gradient or directly cross-gradient of the ORC. Conclusions from the laboratory study were that ORC may provide an aerobic zone in the Child's Pad barrier as far as 1 m directly down-gradient of the sock during periods of high flows (6.9 m/day). Copyright 1999 Elsevier Science B.V.

Child's Pad is a gravel construction surface that was contaminated with petroleum during oil-field service operations in Deadhorse, Alaska. As part of a remedial action plan, a buffer strip of uncontaminated sandy gravel was placed along sections of the pad boundary. A magnesium peroxide formulation manufactured by Regenesis, and sold as Oxygen Release Compound (ORC), was placed in the buffer strips. The ORC was intended to supply oxygen to aerobic microorganisms capable of degrading petroleum. Studies were conducted in the laboratory to determine initial oxygen release kinetics from ORC in contact with barrier soil. Studies quantified the biotic and abiotic catalytic mechanisms for converting hydrogen peroxide (a possible MgO2 intermediate) and ORC to oxygen and water, the effects of temperature on oxygen release from ORC, and the effect of field exposure on ORC viability. Barrier soil exhibited sufficient catalytic activity to convert hydrogen peroxide to oxygen faster than the expected biological demand. The oxygen evolution rate (OER) from ORC was lower at 7 degrees C than 21 degrees C by more than two times. The ORC recovered from Child's Pad after less than 1 year retained nearly all of the original available oxygen, although physical bridging was evident.

Children with specific speech and language disorders are part of a special needs population whose educational and therapeutic needs have been provided for in a variety of settings over the last fifty years. Changes have been implemented in response to a range of legislation. This has also had implications for the delivery and type of provision of the children's education and therapy. The National Health Service and local education authorities (LEAs) have had to respond to legislation and continue to provide for the full range of specific speech and language disorders. This paper will outline how therapeutic input has had to adapt to the changing educational context. Changes in delivery have necessitated a redefinement of roles and adjustments in collaborative working.