Generalised gamma bidding model

A generalised gamma bidding model is presented, which incorporates many previous models. The log likelihood equations are provided. Using a new method of testing, variants of the model are fitted to some real data for construction contract auctions to find the best fitting models for groupings of bidders. The results are examined for simplifying assumptions, including all those in the main literature. These indicate no one model to be best for all datasets. However, some models do appear to perform significantly better than others and it is suggested that future research would benefit from a closer examination of these.

Facile mutant identification via a single parental backcross method and application of whole genome sequencing based mapping pipelines

Forward genetic screens have identified numerous genes involved in development and metabolism, and remain a cornerstone of biological research. However, to locate a causal mutation, the practice of crossing to a polymorphic background to generate a mapping population can be problematic if the mutant phenotype is difficult to recognize in the hybrid F2 progeny, or dependent on parental specific traits. Here in a screen for leaf hyponasty mutants, we have performed a single backcross of an Ethane Methyl Sulphonate (EMS) generated hyponastic mutant to its parent. Whole genome deep sequencing of a bulked homozygous F2 population and analysis via the Next Generation EMS mutation mapping pipeline (NGM) unambiguously determined the causal mutation to be a single nucleotide polymorphisim (SNP) residing in HASTY, a previously characterized gene involved in microRNA biogenesis. We have evaluated the feasibility of this backcross approach using three additional SNP mapping pipelines; SHOREmap, the GATK pipeline, and the samtools pipeline. Although there was variance in the identification of EMS SNPs, all returned the same outcome in clearly identifying the causal mutation in HASTY. The simplicity of performing a single parental backcross and genome sequencing a small pool of segregating mutants has great promise for identifying mutations that may be difficult to map using conventional approaches.

A rapid and simple method of assaying plants transformed with hygromycin or PPT resistance genes

A very simple leaf assay is described that rapidly and reliably identifies transgenic plants expressing the hygromycin resistance gene, hph or the phosphinothricin resistance gene, bar. Leaf tips were cut from plants propagated either in the glasshouse or in tissue culture and the cut surface embedded in solid medium containing the appropriate selective agent. Non-transgenic barley or rice leaf tips had noticeable symptoms of either bleaching or necrosis after three days on the medium and were completely bleached or necrotic after one week. Transgenic leaf tips remained green and healthy over this period. This gave unambiguous discrimination between transgenic and non-transgenic plants. The leaf assay was also effective for dicot plants tested (tobacco and peas).

A Near-Infrared Reflectance Spectroscopy Method for Direct Analysis of Several Chemical Components and Properties of Fruit, for Example, Chinese Hawthorn

Near-infrared spectroscopy (NIRS) calibrations were developed for the discrimination of Chinese hawthorn (Crataegus pinnatifida Bge. var. major) fruit from three geographical regions as well as for the estimation of the total sugar, total acid, total phenolic content, and total antioxidant activity. Principal component analysis (PCA) was used for the discrimination of the fruit on the basis of their geographical origin. Three pattern recognition methods, linear discriminant analysis, partial least-squares-discriminant analysis, and back-propagation artificial neural networks, were applied to classify and compare these samples. Furthermore, three multivariate calibration models based on the first derivative NIR spectroscopy, partial least-squares regression, back-propagation artificial neural networks, and least-squares-support vector machines, were constructed for quantitative analysis of the four analytes, total sugar, total acid, total phenolic content, and total antioxidant activity, and validated by prediction data sets.

Development of the Rapid Assessment, Prioritisation and Referral Tool (RAPaRT) for multidisciplinary teams in emergency care settings

Objective This investigation utilised the expertise of allied members of multidisciplinary teams working in emergency care settings to develop and validate a Rapid Assessment Prioritisation and Referral Tool (RAPaRT). This instrument is intended for use among patients (with non-life threatening acuity) presenting to emergency care settings to indicate when referral to an allied member of the multidisciplinary team is warranted. Method This three stage instrument development and validation study included: a Delphi panel process to determine key criteria to guide instrument development and identify potential items to be carried forward for testing (stage 1); a prospective cohort of consecutive admissions (n=153) to investigate item sensitivity and specificity and retain only the most suitable items (stage 2); then final consultation with the Delphi panel to ensure the final instrument was clinically amenable (stage 3). Results 23 potential items were identified following stage 1. At the completion of item sensitivity and specificity analysis and in consultation with the Delphi panel, seven items were retained in the instrument. Area under the receiver operating characteristic curve was 0.803 for these seven items in predicting when a referral was warranted. Final consultation with the Delphi panel members also resulted in the addition of an open ended (eighth) item to allow description of any infrequent, but important, reason for referral. Conclusions The RAPaRT has demonstrated substantial promise as an efficient clinically amenable instrument to assist multidisciplinary teams in emergency care settings. Further research to investigate the wider implementation of the RAPaRT is warranted.

Local stress-strain distribution and load transfer across cartilage matrix at micro-scale using combined microscopy-based finite element method

Articular cartilage is the load-bearing tissue that consists of proteoglycan macromolecules entrapped between collagen fibrils in a three-dimensional architecture. To date, the drudgery of searching for mathematical models to represent the biomechanics of such a system continues without providing a fitting description of its functional response to load at micro-scale level. We believe that the major complication arose when cartilage was first envisaged as a multiphasic model with distinguishable components and that quantifying those and searching for the laws that govern their interaction is inadequate. To the thesis of this paper, cartilage as a bulk is as much continuum as is the response of its components to the external stimuli. For this reason, we framed the fundamental question as to what would be the mechano-structural functionality of such a system in the total absence of one of its key constituents-proteoglycans. To answer this, hydrated normal and proteoglycan depleted samples were tested under confined compression while finite element models were reproduced, for the first time, based on the structural microarchitecture of the cross-sectional profile of the matrices. These micro-porous in silico models served as virtual transducers to produce an internal noninvasive probing mechanism beyond experimental capabilities to render the matrices micromechanics and several others properties like permeability, orientation etc. The results demonstrated that load transfer was closely related to the microarchitecture of the hyperelastic models that represent solid skeleton stress and fluid response based on the state of the collagen network with and without the swollen proteoglycans. In other words, the stress gradient during deformation was a function of the structural pattern of the network and acted in concert with the position-dependent compositional state of the matrix. This reveals that the interaction between indistinguishable components in real cartilage is superimposed by its microarchitectural state which directly influences macromechanical behavior.

A reciprocal collaborative method using relevance feedback and feature importance

In a people-to-people matching systems, filtering is widely applied to find the most suitable matches. The results returned are either too many or only a few when the search is generic or specific respectively. The use of a sophisticated recommendation approach becomes necessary. Traditionally, the object of recommendation is the item which is inanimate. In online dating systems, reciprocal recommendation is required to suggest a partner only when the user and the recommended candidate both are satisfied. In this paper, an innovative reciprocal collaborative method is developed based on the idea of similarity and common neighbors, utilizing the information of relevance feedback and feature importance. Extensive experiments are carried out using data gathered from a real online dating service. Compared to benchmarking methods, our results show the proposed method can achieve noticeable better performance.

Malnutrition in hospitalised patients and clinical outcomes : a missed opportunity?

This research programme has resulted in 5 published papers in international peer-reviewed journals and contributed to better outcomes for patients. It has provided clear evidence that the adverse outcomes of malnutrition are not just a consequence of the disease process, and lead to substantial increases in length of hospital stay, readmission rate, mortality and hospitalisation cost when compared with well-nourished patients of similar diagnoses and complexities. The research programme led to the development and validation of a new nutrition screening tool called 3-Minute Nutrition Screening (3-MinNS). It has also implemented quality improvement initiatives which proved successful in improving the compliance to 3-MinNS and ensuring referral of malnourished or 'at risk' patients to dietitians. Finally, this research programme has provided an effective method for following up malnourished patients post-discharge, which resulted in improved nutritional status and quality of life.

A novel method for analysing lighting variance

Robust descriptor matching across varying lighting conditions is important for vision-based robotics. We present a novel strategy for quantifying the lighting variance of descriptors. The strategy works by utilising recovered low dimensional mappings from Isomap and our measure of the lighting variance of each of these mappings. The resultant metric allows different descriptors to be compared given a dataset and a set of keypoints. We demonstrate that the SIFT descriptor typically has lower lighting variance than other descriptors, although the result depends on semantic class and lighting conditions.

Stiffness-damping matching method of an ECAS system based on LQG control

A novel method of matching stiffness and continuous variable damping of an ECAS (electronically controlled air suspension) based on LQG (linear quadratic Gaussian) control was proposed to simultaneously improve the road-friendliness and ride comfort of a two-axle school bus. Taking account of the suspension nonlinearities and target-height-dependent variation in suspension characteristics, a stiffness model of the ECAS mounted on the drive axle of the bus was developed based on thermodynamics and the key parameters were obtained through field tests. By determining the proper range of the target height for the ECAS of the fully-loaded bus based on the design requirements of vehicle body bounce frequency, the control algorithm of the target suspension height (i.e., stiffness) was derived according to driving speed and road roughness. Taking account of the nonlinearities of a continuous variable semi-active damper, the damping force was obtained through the subtraction of the air spring force from the optimum integrated suspension force, which was calculated based on LQG control. Finally, a GA (genetic algorithm)-based matching method between stepped variable damping and stiffness was employed as a benchmark to evaluate the effectiveness of the LQG-based matching method. Simulation results indicate that compared with the GA-based matching method, both dynamic tire force and vehicle body vertical acceleration responses are markedly reduced around the vehicle body bounce frequency employing the LQG-based matching method, with peak values of the dynamic tire force PSD (power spectral density) decreased by 73.6%, 60.8% and 71.9% in the three cases, and corresponding reduction are 71.3%, 59.4% and 68.2% for the vehicle body vertical acceleration. A strong robustness to variation of driving speed and road roughness is also observed for the LQG-based matching method.

Use of a photographic food diary method to document dietary intake in people with Parkinson's Disease

Cognitive impairment and physical disability are common in Parkinson’s disease (PD). As a result diet can be difficult to measure. This study aimed to evaluate the use of a photographic dietary record (PhDR) in people with PD. During a 12-week nutrition intervention study, 19 individuals with PD kept 3-day PhDRs on three occasions using point-and-shoot digital cameras. Details on food items present in the PhDRs and those not photographed were collected retrospectively during an interview. Following the first use of the PhDR method, the photographer completed a questionnaire (n=18). In addition, the quality of the PhDRs was evaluated at each time point. The person with PD was the sole photographer in 56% of the cases, with the remainder by the carer or combination of person with PD and the carer. The camera was rated as easy to use by 89%, keeping a PhDR was considered acceptable by 94% and none would rather use a “pen and paper” method. Eighty-three percent felt confident to use the camera again to record intake. Of the photos captured (n=730), 89% were of adequate quality (items visible, in-focus), while only 21% could be used alone (without interview information) to assess intake. Over the study, 22% of eating/drinking occasions were not photographed. PhDRs were considered an easy and acceptable method to measure intake among individuals with PD and their carers. The majority of PhDRs were of adequate quality, however in order to quantify intake the interview was necessary to obtain sufficient detail and capture missing items.