The selection of subcontractors: is price the major factor?

The philosophy of ‘lowest price wins’ in the selection of subcontractors often leads to problems with quality of work and claims for further costs. Since Latham (1994), many models have offered selection methods that take account of a wide range of quality criteria as well as price. A review of existing literature and models enables a list of selection criteria to be drawn up and a survey ascertains which selection criteria are considered most important and whether opinions change when faced with different types of project. The results of the questionnaire are analysed through the use of Simple Relative Indexes, Spearman’s Rank Correlation Coefficient tests and a number of T-tests. It is established that price is no longer considered the only important factor in subcontractor selection, and that health and safety, past performance, and insurance cover are considered equally important and, in some scenarios, more important than price

The methodological and ethical issues associated with patient-reported outcome measurement in clinical trials

The doctoral research forming this thesis used mixed-methods to explore methodological and ethical issues associated with patient-reported outcome (PRO) measurement in clinical trials. A qualitative study of trial staff suggested there are perceived inconsistencies in the administration and management of PROs in some UK trials which could undermine PRO trial results and introduce bias. In addition, the study found that staff reported intermittently encountering ‘concerning’ PRO data in trials, but were unsure how it should be managed. A large-scale survey of UK-based trial staff and management demonstrated the genralisiability of these findings. A systematic review of PRO literature for front-line data collection staff found guidance was lacking. A large-scale review of PRO-specific literature for trial protocol developers suggested guidelines were inconsistent and difficult to access. Finally, using a novel PRO protocol checklist, a systematic review of trial protocols found that PRO information was commonly absent, even where a PRO was the primary outcome. In conclusion, the thesis highlights a need for the development of comprehensive consensus-based PRO guidelines addressing protocol development, training and the management of ‘concerning’ PRO data in trials; aiming to facilitate improvements in PRO protocol content and PRO assessment, whilst protecting the interests of trial participants

¹³CO and C¹⁸O observations of S140: delineation of the outflow structure, a study of fractionation effects and comparison with CI observations

The outflow and photon-dominated region (PDR) associated with the S140 complex have been observed at high resolution (~14 arcsec) in the 13CO and C18O J=3→2 lines. The C18O map confirms earlier C17O J=3→2line observations (Minchin et al. 1994) that show an `arc' of emission observed to the south of the peak, and also reveals a similar (and more prominent) arc feature to the east, a region not covered by the C17O map. This is a particularly fine example of the classic `tuning fork' morphology, where emission at the ambient cloud velocity is tracing the outflow cavity wall of the blueshifted lobe. The N(13CO)/N(C18O) ratio has been plotted against extinction and fits the power law relation N(13CO)/N(C18O)=21Av-0.35. The highest values, as expected, occur for observed positions towards the PDR, with N(13CO)/N(C18O) exceeding the terrestrial value (5.5) for Av ≤40 magnitudes. In the outermost parts of the cloud (Av ≤10 magnitudes) the N(13CO)/N(C18O) ratio is largest, up to 20. The increased fractionation may be due to higher photoionization of the optically thinner isotope, C18O. There is a close correlation between N(CI)/N(CO) and visual extinction over a wide extinction range (Av=3-100 mags.). The best fit power law is N(CI)/N(CO)=4.2Av0.9. For positions toward the outflow (Av~50-100) N(CI)/N(CO) ~0.1(0.07-0.12). N(CI)/N(CO) increases with decreasing extinction to ~1 for Av≤5 mags., corresponding to positions near the edge of the cloud. A detailed comparison of antenna temperatures and linewidths for the 13CO, C18O and CI lines is presented. The 13CO and C18O antenna temperatures and linewidths are closely correlated, and imply the emission, for both isotopes, emanates from gas that is in LTE and is well mixed. The CI emission from the PDR implies that here the atomic carbon is in LTE, but occupies a different volume of gas than the isotopic CO. Towards the outflow the CI linewidths are systematically broadened relative to those for the isotopic CO lines. This is interpreted as evidence that atomic carbon is produced by the effect of shocks on the chemical and physical processes at the interface between a stellar wind and the outflow cavity wall

A submillimetre continuum study of S 140/L 1204: the detection of three new submillimetre sources and a self-consistent model for the region

We present submillimetre continuum observations of the L 1204/S 140 complex in broad bands centred at 450, 800 and 1100μm. The morphology of the region is similar at all three wavelengths, with the emitting region compact, about 90 arcsec in diameter, and centrally peaked around the cloud core. Three new submillimetre continuum sources are observed which are not coincident with any previously known near or mid-infrared sources. We designate the sources S 140-SMM1-3. SMM1 is roughly coincident with a previously known NH3 clump and 2.7mm source, and near-IR reflection nebulosity from the surface of SMM2 has previously been seen. The three submillimetre continuum sources may be protostellar in nature, although it is not possible to determine whether they are gravitationally bound, since virial mass estimates are disrupted by the presence of an energetic bipolar outflow. For this reason, earlier claims that the 2.7mm source in SMM1 is collapsing appear somewhat premature. The observation that SMM1 and SMM2 lie either side of the infrared sources, in a line roughly perpendicular to the direction of the bipolar outflow, imply they may be the remnants of a large-scale disk. Comparison of the continuum emission with previous high resolution CS, NH3 and CI observations provides evidence that, for the first time, demonstrates the photon-dominated region and outflow are intimately linked. The only scenario that is able to explain all of the available molecular and atomic emission line data and our submillimetre continuum data, is one in which the outflow has expanded towards the edge of the molecular cloud and the edge of the blueshifted outflow lobe is now bounded by the expanding HII region. The NH3 and continuum emission emanate from the inner edge of the outflow lobe, shielded from the external UV field. A plot of the 800μm flux against N(C18O) implies that the dust/gas mass ratio is close to the canonical value (~1%) at the lower end of the observed extinction range (Av≤70), but for the highest observed extinctions (Av=70-100) the continuum flux density increases rapidly, implying a higher dust/gas mass ratio is appropriate (~2-5%), possibly indicating freeze-out of gas onto dust grains

Carbon monoxide and far-infrared observations of the S 155-Cepheus B region

We present maps of the CO J = 3-2 and 13CO J = 2→1 molecular line and mid- to far-infrared continuum emission of the interface between the Cepheus B molecular cloud and the S155 H II region. Far-infrared dust color temperature and optical depth maps show the molecular cloud to be externally heated and that the edge of the cloud is compressed by the expansion of S155. The data are compared with current models, and various dust grain parameters are derived. A hotspot is observed in the CO J = 3→2 emission line, at a position coincident with the radio continuum and infrared emission peaks. The infrared, radio continuum, and molecular line emission from the hotspot are all consistent with it being a compact H II region, ionized by an embedded B1-B0.5 star. The position of the compact H II region, adjacent to the northwestern edge of Cep B, suggests it is the product of a phase of sequential OB star formation, which has already been responsible for the youngest subgroup of the Cepheus OB3 association. The mass of the cloud is estimated to be ~100-200M⊙</sub

Genome stability pathways in head and neck cancers

Genomic instability underlies the transformation of host cells toward malignancy, promotes development of invasion and metastasis and shapes the response of established cancer to treatment. In this review, we discuss recent advances in our understanding of genomic stability in squamous cell carcinoma of the head and neck (HNSCC), with an emphasis on DNA repair pathways. HNSCC is characterized by distinct profiles in genome stability between similarly staged cancers that are reflected in risk, treatment response and outcomes. Defective DNA repair generates chromosomal derangement that can cause subsequent alterations in gene expression, and is a hallmark of progression toward carcinoma. Variable functionality of an increasing spectrum of repair gene polymorphisms is associated with increased cancer risk, while aetiological factors such as human papillomavirus, tobacco and alcohol induce significantly different behaviour in induced malignancy, underpinned by differences in genomic stability. Targeted inhibition of signalling receptors has proven to be a clinically-validated therapy, and protein expression of other DNA repair and signalling molecules associated with cancer behaviour could potentially provide a more refined clinical model for prognosis and treatment prediction. Development and expansion of current genomic stability models is furthering our understanding of HNSCC pathophysiology and uncovering new, promising treatment strategies

Irrigation Systems Management

Management of irrigation systems should be based on the desired objectives or outcomes consistent with economic, energy, environmental, labor, water, and resource constraints. Goals can vary from maximizing profit, producing a contracted yield, optimizing water resource use, maintaining the quality of produce, or assuring an attractive landscape. Managers cannot achieve these goals without considering the performance of the irrigation system. This chapter discusses the basic characteristics of various irrigation systems, defines terms that quantify performance, describes basic requirements all systems must provide, gives a range of attributes for systems, and discusses how water supply requirements are governed by ET and system characteristics. Detailed characteristics of specific systems are presented in later chapters. The key here is to understand the basic systems and their relative performance

Irrigation Systems Management

Like most textbooks, this book grew out of our desire to have written material that matches the educational needs of both the students and the instructor of a college course, in this case a course entitled Irrigation Systems Management. The book is the culmination of course notes which have been in development and use for nearly 30 years. The emphasis of this book is on the management of irrigation systems that are used for agricultural crop production. There are two distinct components of the book, starting with the soil-water-plant-atmosphere system and how soil water should be managed to achieve the desired crop production outcomes. This includes in-depth presentations on soil water storage and movement, plant water use, managing the soil water reservoir through irrigation scheduling, and salinity management. The book then shifts to the second component, which is the description and management of the various forms of agricultural irrigation systems along with their water supply. Whether it be a surface, sprinkler, or microirrigation system, the irrigation manager must not only know how much water to apply but also how to manage the system itself to achieve efficient application. High application efficiency can only be realized by minimizing runoff, deep percolation, evaporation, and drift onto non-target areas. Since energy costs are an integral part of the management equation, one chapter in the book deals with the hydraulics and energy requirements of pumping and distributing water. One of the key themes spread throughout the book is providing guidance to irrigation managers on how to improve irrigation water productivity (production per unit of irrigation water) and minimize water resource contamination. Our goal is for the reader to understand the complexities of irrigation systems and how they are to be managed to meet the water needs of the crop production system. This is not an irrigation engineering design book; we have purposely minimized the presentation of design steps and the supporting equations. The intended audience of the book is upper-level undergraduate students and graduate students who are pursuing degrees in Agricultural or Natural Resource Sciences. Example majors include Agricultural Systems Technology, Agronomy, Crop Science, Mechanized Systems Management (or equivalent), Natural Resources Management, Soil Science, and Water Science. We expect the reader to have a basic understanding of soils, crops, physics, and the application of algebraic equations. We have also tried to add enough advanced material to challenge graduate students when the book is used in courses that are taught simultaneously at the undergraduate and graduate level. We hope the book will match the needs of students who plan to work in irrigation and related industries, university extension and outreach, private consulting, government service, or production agriculture and that it will continue to serve as a useful reference to them following completion of their formal education

Environmental and genetic factors associated with Solanesol accumulation in potato leaves

Solanesol is a high value 45-carbon, unsaturated, all-trans-nonaprenol isoprenoid. Recently solanesol has received particular attention because of its utility, both in its own right and as a precursor in the production of numerous compounds used in the treatment of disease states. Solanesol is found mainly in solanaceous crops such as potato, tomato, tobacco and pepper where it accumulates in the foliage. There is considerable potential to explore the extraction of solanesol from these sources as a valuable co-product. In this study we have characterised the genetic variation in leaf solanesol content in a biparental, segregating diploid potato population. We demonstrate that potato leaf solanesol content is genetically controlled and identify several quantitative trait loci associated with leaf solanesol content. Transient over-expression of genes from the methylerythritol 4-phosphate (MEP) and mevalonic acid (MVA) pathways, either singly or in combination, resulted in enhanced accumulation of solanesol in leaves of Nicotiana benthamiana, providing insights for genetically engineering the pathway. We also demonstrate that in potato, leaf solanesol content is enhanced by up to six-fold on exposure to moderately elevated temperature and show corresponding changes in expression patterns of MEP and MVA genes. Our combined approaches offer new insights into solanesol accumulation and strategies for developing a bio-refinery approach to potato production