Low temperature/short duration steaming as a sustainable method of soil disinfection

This report was presented at the UK Organic Research 2002 Conference. Soil samples containing resting structures of fungal crop pathogens (Verticillium dahliae, Sclerotinia sclerotiorum, Sclerotium cepivorum, Pythium ultimum), potato cyst nematodes (Globodera rostochiensis and Globodera pallida) and weeds (Chenopodium album and Agropyron repens) were treated with aerated steam in the laboratory at temperatures ranging from 50–80oC in a specially constructed apparatus. Steaming at 50 or 60oC for three minutes, followed by an eight-minute resting period in the steamed soil and immediate removal from the soil thereafter, resulted in 100% kill of all weeds, fungi and nematodes. Low temperature/ short duration soil steaming could become a sustainable alternative to chemical or high-temperature steam soil disinfestation

Continuous two-phase flow miniaturised bioreactor for monitoring anaerobic biocatalysis by pentaerythritol tetranitrate reductase

A novel continuous recirculating two-phase flow miniaturised bioreactor was developed for biocatalytic transformations with the enzyme pentaerythritol tetranitrate reductase using on-chip spectroscopic detection of the organic and aqueous phases. A phase separation technique is described that uses electrostatic attraction to force charged droplets to merge back into the aqueous phase and thus allow the monitoring of both reaction phases during enzymatic turnover. We report an increased rate of enzyme catalysed reduction of trans-2-(2-nitrovinyl) thiophene, which was used as a model system to demonstrate the principles of the bioreactor design, compared to conventional macroscale experiments. Additional data obtained with ketoisophorone, trans-cinnamaldehyde and 2-methylmaleimide support our findings and provide a basis for improving the chemistry of biocatalysis

Electro-enzymatic viologen-mediated substrate reduction using pentaerythritol tetranitrate reductase and a parallel, segmented fluid flow system

Many redox enzymes require expensive reduced cofactors like NAD(P)H which need to be recycled during catalysis, presenting a major cost and technical barrier to industrial exploitation. An electrochemical biphasic microfluidic setup is presented here, in which these cofactors are replaced by a mediator (methyl viologen) that acts by feeding electrons into the active site of the enzyme pentaerythritol tetranitrate reductase (PETNR). In this microfluidic recirculation setup, both enzyme and mediator remain in the reactor for reuse, allowing easy product recovery. System optimisation studies were performed using 2-cyclohexen-1-one as a model substrate prior to the investigation of a variety of different substrates whose reduction rates were determined to be 15-70% of those obtained when NADPH was used as sole electron donor. Additional data obtained with a thermophilic 'ene' reductase (TOYE) support the potential universality of this device for possible industrial applications

A novel system for wheelchair stability assessment : design and initial results

Wheelchairs should provide safe and reliable functioning in various road conditions and situations, ease of propulsion, and high maneuverability. Often, wheelchairs need further modification and installation of additional equipment (ventilators, oxygen cylinders, etc) which affect their stability. Wheelchair stability is also dependent on a user's body characteristics that can result in a shifting of the centre of mass e.g. limb amputations, and obesity, etc. Adaptation of the wheelchair requires additional assessment and wheelchair tuning by highly skilled rehabilitation engineers. In this paper, we discuss the design and initial testing of a novel wheelchair stability assessment system. The developed WheelSense system consists of a force platform that senses the weight distribution of the wheelchair, the centre of the contact points, and the distances between contact points of the wheels. The measurement platform is linked via WiFi connection to a portable tablet computer where the platform's sensor signals are processed and the wheelchair stability parameters are calculated. An intuitive touchscreen GUI is used for visualization of the stability results and navigation through separate measurement modes. The mechanical platform was designed to be foldable and light-weighted and thus, to be easily transportable which gives additional advantages when the system is used outside of a clinical engineering department. The initial design is being evaluated through four prototype systems installed for clinical testing in 3 large hospitals in the UK. The initial results indicate that the developed measurement system possesses high accuracy and ease of operatio

Establishing user needs for a stability assessment tool to guide wheelchair prescription

Purpose: The WheelSense project aims to develop a system for assessing the stability and performance of wheelchairs through a user-centred design process. This study sought to capture user needs and define the specification for the system. Method: A mixed methods approach was adopted. An online survey was completed by 98 participants working in wheelchair provision. The results were built upon through 10 semi-structured interviews and one focus group (n = 5) with professionals working in wheelchair provision in three NHS Trusts in the UK. Results: The results provided a picture of the current UK practice in stability testing. Issues with the reliability and usefulness of the existing methods used to assess the stability and performance of wheelchairs were highlighted. Requirements for a new system were ascertained. These included improved accuracy of tipping angles, features to support record keeping, improved client/carer education support and ability to model or predict client-wheelchair system performance in different configurations. Conclusions: The paper concludes that there is a need for improved tools to determine the stability of the client-wheelchair system and support the prescription process, to ensure client safety and optimum equipment performance. A list of requirements has been produced to guide the future development of WheelSense. Implications for Rehabilitation The results of this survey and interview-based study present a picture of wheelchair stability testing practices in the UK, and highlight the need for new, more informative methods for guiding wheelchair prescription. The requirements for the design of a new system, or further development of existing tools to support the stability testing and prescription of wheelchairs have been established

The development and testing of a system for wheelchair stability measurement

Wheelchair stability has an impact on safety as well as wheelchair performance, propulsion and manoeuvrability. Wheelchair stability is affected by the addition of life supporting heavy equipment, e.g. ventilators and oxygen cylinders, as well as the characteristics of the user e.g. limb amputations, obesity. The aim of the research described here was to develop and test a stability assessment system that would guide and support the adjustment of wheelchairs to individual needs, characteristics and lifestyles. The resulting system provides assessment of centre of gravity and wheelchair stability and calculates the wheelchair tipping angles. The system consists of a force platform that senses the weight distribution of the wheelchair and calculates the centres of the contact points of the wheels and the distances between them. The measurement data are transferred via a WiFi connection to a portable tablet computer where wheelchair stability parameters are calculated. A touch screen GUI provides visualization of the stability results and navigation through the measurement modes. The developed new concept has been evaluated through technical laboratory-based testing to determine the validity of the data collected. Initial testing has been undertaken within the clinical setting in 3 large hospitals in the UK. Initial results suggest that Wheelsense® provides a valuable tool to support clinical judgement

Using Fourier transform IR spectroscopy to analyze biological materials

IR spectroscopy is an excellent method for biological analyses. It enables the nonperturbative, label-free extraction of biochemical information and images toward diagnosis and the assessment of cell functionality. Although not strictly microscopy in the conventional sense, it allows the construction of images of tissue or cell architecture by the passing of spectral data through a variety of computational algorithms. Because such images are constructed from fingerprint spectra, the notion is that they can be an objective reflection of the underlying health status of the analyzed sample. One of the major difficulties in the field has been determining a consensus on spectral pre-processing and data analysis. This manuscript brings together as coauthors some of the leaders in this field to allow the standardization of methods and procedures for adapting a multistage approach to a methodology that can be applied to a variety of cell biological questions or used within a clinical setting for disease screening or diagnosis. We describe a protocol for collecting IR spectra and images from biological samples (e.g., fixed cytology and tissue sections, live cells or biofluids) that assesses the instrumental options available, appropriate sample preparation, different sampling modes as well as important advances in spectral data acquisition. After acquisition, data processing consists of a sequence of steps including quality control, spectral pre-processing, feature extraction and classification of the supervised or unsupervised type. A typical experiment can be completed and analyzed within hours. Example results are presented on the use of IR spectra combined with multivariate data processing