Use of oxygen sensors for the non destructive measurement of oxygen in packaged food and beverage products and its impact on product quality and shelf life

The principal objective of this thesis was to investigate the ability of reversible optical O2 sensors to be incorporated into food/beverage packaging systems to continuously monitor O2 levels in a non-destructive manner immediately postpackaging and over time. Residual levels of O2 present in packs can negatively affect product quality and subsequently, product shelf-life, especially for O2-sensitive foods/beverages. Therefore, the ability of O2 sensors to continuously monitor O2 levels present within food/beverage packages was considered commercially relevant in terms of identifying the consequences of residual O2 on product safety and quality over time. Research commenced with the development of a novel range of O2 sensors based on phosphorescent platinum and palladium octaethylporphyrin-ketones (OEPk) in nano-porous high density polyethylene (HDPE), polypropylene (PP) polytetrafluoroethylene (PTFE) polymer supports. Sensors were calibrated over a temperature range of -10°C to +40°C and deemed suitable for food and beverage packaging applications. This sensor technology was used and demonstrated itself effective in determining failures in packaging containment. This was clearly demonstrated in the packaging of cheese string products. The sensor technology was also assessed across a wide range of packaged products; beer, ready-to-eat salad products, bread and convenience-style, muscle-based processed food products. The O2 sensor technology performed extremely well within all packaging systems. The sensor technology adequately detected O2 levels in; beer bottles prior to and following pasteurisation, modified atmosphere (MA) packs of ready-to-eat salad packs as respiration progressed during product storage and MA packs of bread and convenience-style muscle-based products as mycological growth occurred in food packs over time in the presence and absence of ethanol emitters. The use of the technology, in conjunction with standard food quality assessment techniques, showed remarkable usefulness in determining the impact of actual levels of O2 on specific quality attributes. The O2 sensing probe was modified, miniaturised and automated to screen for the determination of total aerobic viable counts (TVC) in several fish species samples. The test showed good correlation with conventional TVC test (ISO:4833:2003), analytical performance and ruggedness with respect to variation of key assay parameters (probe concentration and pipetting volume). Overall, the respirometric fish TVC test was simple to use, possessed a dynamic microbial range (104-107 cfu/g sample), had an accuracy of +/- one log(cfu/g sample) and was rapid. Its ability to assess highly perishable products such as fish for total microbial growth in <12 hr demonstrates commercial potential.

NgBR is essential for endothelial cell glycosylation and vascular development.

NgBR is a transmembrane protein identified as a Nogo-B-interacting protein and recently has been shown to be a subunit required for cis-prenyltransferase (cisPTase) activity. To investigate the integrated role of NgBR in vascular development, we have characterized endothelial-specific NgBR knockout embryos. Here, we show that endothelial-specific NgBR knockout results in embryonic lethality due to vascular development defects in yolk sac and embryo proper. Loss of NgBR in endothelial cells reduces proliferation and promotes apoptosis of the cells largely through defects in the glycosylation of key endothelial proteins including VEGFR2, VE-cadherin, and CD31, and defective glycosylation can be rescued by treatment with the end product of cisPTase activity, dolichol phosphate. Moreover, NgBR functions in endothelial cells during embryogenesis are Nogo-B independent. These data uniquely show the importance of NgBR and protein glycosylation during vascular development.

A life cycle model for product-service systems design

Western manufacturing companies are developing innovative ways of delivering value that competes with the low cost paradigm. One such strategy is to deliver not only products, but systems that are closely aligned with the customer value proposition. These systems are comprised of integrated products and services, and are referred to as Product-Service Systems (PSS). A key challenge in PSS is supporting the design activity. In one sense, PSS design is a further extension of concurrent engineering that requires front-end input from the additional downstream sources of product service and maintenance. However, simply developing products and service packages is not sufficient: the new design challenge is the integrated system. This paper describes the development of a PSS data structure that can support this integrated design activity. The data structure is implemented in a knowledge base using the Protégé knowledge base editor.

Mammalian cell production of a respiratory syncytial virus (RSV) candidate vaccine recovered using a product-specific affinity column

The recombinant production of a respiratory syncytial virus (RSV) candidate vaccine BBG2Na in baby hamster kidney cells (BHK-21 cells) was investigated. BBG2Na consists of a serum-albumin-binding region (BB) fused to a 101-amino-acid fragment of the RSV G-protein. Semliki Forest virus-based expression vectors encoding both intracellular and secreted forms of BBG2Na were constructed and found to be functional. Affinity recovery of BBG2Na employing human serum albumin columns was found to be inefficient due to the abundance of BSA in the applied samples. Instead, a strategy using a tailor-made affinity ligand based on a combinatorially engineered Staphylococcus aureus protein A domain, showing specific binding to the G-protein part of the product, was evaluated. In conclusion, a strategy for production and successful recovery of BBG2Na in mammalian cells was created, through the development of a product-specific affinity column.

Advanced glycation end product (AGE) accumulation on Bruch's membrane: links to age-related RPE dysfunction.

PURPOSE: Advanced glycation end products (AGEs) accumulate during aging and have been observed in postmortem eyes within the retinal pigment epithelium (RPE), Bruch's membrane, and subcellular deposits (drusen). AGEs have been associated with age-related dysfunction of the RPE-in particular with development and progression to age-related macular degeneration (AMD). In the present study the impact of AGEs at the RPE-Bruch's membrane interface was evaluated, to establish how these modifications may contribute to age-related disease. METHODS: AGEs on Bruch's membrane were evaluated using immunohistochemistry. A clinically relevant in vitro model of substrate AGE accumulation was established to mimic Bruch's membrane ageing. Responses of ARPE-19 growing on AGE-modified basement membrane (AGE-BM) for 1 month were investigated by using a microarray approach and validated by quantitative (q)RT-PCR. In addition to identified AGE-related mRNA alterations, lysosomal enzyme activity and lipofuscin accumulation were also studied in ARPE-19 grown on AGE-BM. RESULTS: Autofluorescent and glycolaldehyde-derived AGEs were observed in clinical specimens on Bruch's membrane and choroidal extracellular matrix. In vitro analysis identified a range of dysregulated mRNAs in ARPE-19 exposed to AGE-BM. Altered ARPE-19 degradative enzyme mRNA expression was observed on exposure to AGE-BM. AGE-BM caused a significant reduction in cathepsin-D activity in ARPE-19 (P

Development of a novel PCR assay for the identification of the black yeast, Exophiala (Wangiella) dermatitidis from adult patients with cystic fibrosis (CF)

Cystic fibrosis (CF) patients may suffer increased morbidity and mortality through colonisation, allergy and invasive infection from fungi. The black yeast, Exophiala dermatitidis (synonym Wangiella dermatitidis) has been found with increasing frequency in sputum specimens of CF patients, with reported isolation rates ranging from 1.1 to 15.7%. At present, no diagnostic PCR exists to aid with the clinical laboratory detection and identification of this organism. A novel species-specific PCR-based assay was developed for the detection of E. dermatitidis, based on employment of rDNA operons and interspacer (ITS) regions between these rDNA operons. Two novel primers, (designated ExdF & ExdR) were designed in silico with the aid of computer-aided alignment software and with the alignment of multiple species of Exophiala, as well as with other commonly described yeasts and filamentous fungi within CF sputum, including Candida. Aspergillus and Scedosporium. An amplicon of approximately 455 by was generated, spanning the partial ITS I region - the complete 5.8S rDNA region - partial ITS2 region, employing ExdF (forward primer [16-mer], 5'-CCG CCT ATT CAG GTC C-3' and ExdR (reverse primer [16-mer], 5'-TCT CTC CCA CTC CCG C-3', was employed and optimised on extracted genomic DNA from a well characterised culture of E. dermatitidis, as well as with high quality genomic DNA template from a further 16 unrelated fungi, including Candida albicans, C. dubliniensis, C. parapsilosis, C. glabrata, Scedosporium apiospermum, Penicillium sp., Aspergillus fumigatus, Aspergillus versicolor, Pichia guilliermondii, Rhodotorula sp., Trichosporon sp., Aureobasidium pullulans, Fusarium sp., Mucor hiemalis, Bionectria ochroleuca, Gibberella pulicaris. Results demonstrated that only DNA from E. dermatitidis gave an amplification product of the expected sire, whilst none of the other fungi were amplifiable. Subsequent employment of this primer pair detected this yeast from mycological cultures from 2/50 (4%) adult CF patients. These two patients were the only patients who were previously shown to have a cultural history of E. dermatitidis from their sputum. E. dermatitidis is a slow-growing fungus, which usually takes up to two weeks to culture in the microbiology laboratory and therefore is slow to detect conventionally, with the risk of bacterial overgrowth from common co-habiting pan- and multiresistant bacterial pathogens from sputum. namely Pseudomonas aeruginosa and Burkholderia cepacia complex organisms, hence this species-specific PCR assay may help detect this organism from CF sputum more specifically and rapidly. Overall, employment of this novel assay nay help in the understanding of the occurrence. aetiology and epidemiology of E. dermatitidis, as an emerging fungal agent in patients with CF. (C) 2008 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.

Development of a novel DNA microarray to detect bacterial pathogens in patients with chronic obstructive pulmonary disease (COPD)

A novel microarray was constructed with DNA PCR product probes targeting species specific functional genes of nine clinically significant respiratory pathogens, including the Gram-positive organisms (Streptococcus pneumoniae, Streptococcus pyogenes), the Gram-negative organisms (Chlamydia pneumoniae, Coxiella burnetii Haemophilus spp., Legionella pneumophila, Moraxella catarrhalis, and Pseudomonas aeruginosa), as well as the atypical bacterium, Mycoplasma pneumoniae. In a "proof-of-concept" evaluation of the developed microarray, the microarray was compared with real-time PCR from 14 sputum specimens from COPD patients. All of the samples positive for bacterial species in real-time PCR were also positive for the same bacterial species using the microarray. This study shows that a microarray using PCR probes is a potentially useful method to monitor the populations of bacteria in respiratory specimens and can be tailored to specific clinical needs such as respiratory infections of particular patient populations, including patients with cystic fibrosis and bronchiectasis. (C) 2010 Elsevier B.V. All rights reserved.

Development of the kinetic model of platinum catalyzed ammonia oxidation in a microreactor

The ammonia oxidation reaction on supported polycrystalline platinum catalyst was investigated in an aluminum-based microreactor. An extensive set of reactions was included in the chemical reactor modeling to facilitate the construction of a kinetic model capable of satisfactory predictions for a wide range of conditions (NH3 partial pressure, 0.01-0.12 atm; O-2 partial pressure, 0.10-0.88 atm; temperature, 523-673 K; contact time, 0.3-0.7 ms). The elementary surface reactions used in developing the mechanism were chosen based on the literature data concerning ammonia oxidation on a Pt catalyst. Parameter estimates for the kinetic model were obtained using multi-response least squares regression analysis using the isothermal plug-flow reactor approximation. To evaluate the model, the behavior of a microstructured reactor was simulated by means of a complete Navier-Stokes model accounting for the reactions on the catalyst surface and the effect of temperature on the physico-chemical properties of the reacting mixture. In this way, the effect of the catalytic wall temperature non-uniformity and the effect of a boundary layer on the ammonia conversion and selectivity were examined. After further optimization of appropriate kinetic parameters, the calculated selectivities and product yields agree very well with the values actually measured in the microreactor. (C) 2002 Elsevier Science B.V. All rights reserved.

Development of a novel UV indicator and dosimeter film

A novel UV indicator is described, comprising nanocrystalline particles of titania dispersed in a film of a polymer, hydroxyl ethyl cellulose (HEC), containing: a mild reducing agent, triethanolamine (TEOA) and a redox indicator, methylene blue (MB). The UV indicator film is blue-coloured in the absence of UV light and loses colour upon exposure to UV light, attaining within a few min a steady-state degree of bleaching that can provide a measure of the irradiance of the incident light. The original blue colour of the film returns once the source of UV light is removed. The spectral characteristics of a typical UV indicator film, and its components, are discussed and the UV-absorbing action of the titania particles highlighted. From the measured %bleaching undergone by a typical UV indicator as a function of light irradiance the indicator appears fully bleached, within 7 min, by a UV irradiance of 3 mW cm (-) or greater. The mechanism by which the UV indicator works is described. The reversible nature of the UV indicator is removed by covering a typical UV indicator with a thin, largely oxygen impermeable, polymer film, such as the regenerated cellulose found in Sellotape(TM). The product is a UV dosimeter, the response of which is related to the intensity and duration of the incident UV light, as well as the amount of titania in the film. A typical UV dosimeter film is fully bleached by 250 mJ cm(-2) of UV light. The possible use of these novel indicators to measure UV exposure levels, irradiance and dose, is discussed.

Sustainability-related media coverage and socioeconomic development: a regional and North–South perspective

Abstract. With this paper we discuss the differences between sustainability-related media agendas across different countries and regions. Utilising a sample of 115 leading national newspapers covering forty-one countries, we show that typically no homogeneous global trends exist with regard to sustainability-related media agendas. Instead, significant differences exist regarding the national-level prioritisations of sustainability-related issues in the countries under review. To some extent, these observed differences can be attributed to different levels of socioeconomic development as measured by Human Development Index scores and gross domestic product per capita. Here, generic differences can be identified between newspapers from the Global North and South, with a range of issues such as climate change emerging as typically Northern issues, whereas issues such as corruption and poverty show significantly higher levels of coverage across newspapers from the Global South. We conclude with a discussion of the results in the context of global environmental governance.

Digital Methods for Process Development in Manufacturing and Their Relevance to Value Driven Design

This paper examines the applicability of a digital manufacturing framework to the implementation of a Value Driven Design (VDD) approach for the development of a stiffened composite panel. It presents a means by which environmental considerations can be integrated with conventional product and process design drivers within a customized, digital environment. A composite forming process is used as an exemplar for the work which creates a collaborative environment for the integration of more traditional design drivers with parameters related to manufacturability as well as more sustainable processes and products. The environmental stakeholder is introduced to the VDD process through a customized product/process/resource (PPR) environment where application specific power consumption and material waste data has been measured and characterised in the process design interface. This allows the manufacturing planner to consider power consumption as a concurrent design driver and the inclusion of energy as a parameter in a VDD approach to the development of efficiently manufactured, sustainable transport systems.

Development of an objective structured clinical examination (OSCE) to assess formulation and extemporaneous dispensing skills in MPharm undergraduates

Background: The use of Objective Structured Clinical Examination (OSCE) in Pharmacy has been explored; however this is the first attempt in Queen’s University School of Pharmacy, Belfast to assess students via this method in a module where chemistry is the main discipline.

Aims: To devise an OSCE to assess undergraduate ability to check extemporaneously dispensed products for clinical and formulation errors. This activity also aims to consider whether it is a viable method of assessment in such a science-based class, from a staff and student perspective.

Method: Students rotated around a number of stations, performing a check of the product, corresponding prescription and formulation record sheet detailing the theory behind the formulation. They were assessed on their ability to spot intentional mistakes at each one.

Results: Of the 79 students questioned, 95% indicated that OSCE made them aware of the importance of the clinical check carried out by the pharmacist. Nearly all of the undergraduates (72 out of 79) felt that OSCE made them aware of the type of mistakes that students make in class. Most (5 out of 7) of the academic team members strongly agreed that it made students aware of ‘point of dispensing’ checks carried out by pharmacists, in addition to helping them to prepare for their exam.

Conclusion: OSCE assesses both scientific and formulation skills, and has increased the diversity of assessment of this module, bringing with it many additional benefits for the undergraduates since it measures their ability to exercise professional judgement in a time- constrained environment and, in this way, mirrors the conditions many pharmacists work within.

Development of a value-added soil conditioner from high shear co-granulation of organic waste and limestone powder

This paper reports on a technical feasibility study of the production of organo-mineral fertiliser from the co-granulation of limestone powders with tea waste. The results from this preliminary study show that the co-granulation of tea waste provided an alternative method of waste recovery, as it converts the waste into a value-added product. Fertiliser granules were successfully produced from various compositions of limestone and tea waste. The effect of tea waste concentration on granule strength was analysed; the granule strength
was in the range 0.2 to 1.8 MPa depending on powder composition; increasing the tea waste mass fraction resulted in a reduction in granule strength.Varying the teawaste to limestone ratio also influenced the compressibility of the granules; the granules compressibility increased with increasing tea waste mass fraction. It was further found that increasing the mass fraction of tea waste in the binary mixture of powder reduced the granule median size of the batch.

The Development of an Immersive Virtual Reality Environment for Manufacturing and Improving Organizational Learning

This paper examines the applicability of an immersive virtual reality (VR) system to the process of organizational learning in a manufacturing context. The work focuses on the extent to which realism has to be represented in a simulated product build scenario in order to give the user an effective learning experience for an assembly task. Current technologies allow the visualization and manipulation of objects in VR systems but physical behaviors such as contact between objects and the effects of gravity are not commonly represented in off the shelf simulation solutions and the computational power required to facilitate these functions remains a challenge. This work demonstrates how physical behaviors can be coded and represented through the development of more effective mechanisms for the computer aided design (CAD) and VR interface.

Development tools for opportunistic pervasive computing

The goal of the POBICOS project is a platform that facilitates the development and deployment of pervasive computing applications destined for networked, cooperating objects. POBICOS object communities are heterogeneous in terms of the sensing, actuating, and computing resources contributed by each object. Moreover, it is assumed that an object community is formed without any master plan; for example, it may emerge as a by-product of acquiring everyday, POBICOS-enabled objects by a household. As a result, the target object community is, at least partially, unknown to the application programmer, and so a POBICOS application should be able to deliver its functionality on top of diverse object communities (we call this opportunistic computing). The POBICOS platform includes a middleware offering a programming model for opportunistic computing, as well as development and monitoring tools. This paper briefly describes the tools produced in the first phase of the project. Also, the stakeholders using these tools are identified, and a development process for both the middleware and applications is presented. © 2009 IEEE.