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1.
Waste Manag ; 102: 598-612, 2020 Feb 01.
Article in English | MEDLINE | ID: mdl-31778971

ABSTRACT

Circular economy principles aim to contribute towards sustainability and resilience through several simultaneous agendas including economic growth, social development and environmental responsibility. Stakeholders from each perspective have their own interests and priorities, which often result in conflict. There are several and varied methodologies which address the decision-making process, however in engineering spheres these techniques are usually limited to optimising resources, time or costs. Decisions that are comprehensive in scope and integrated across all affected systems are required to transition towards a circular economy, effective cross-disciplinary thinking is imperative and cooperation amongst diverse areas is essential. Game theory is a useful technique when analysing the interactions of stakeholders with multiple objectives and perspectives. This paper aims to critically review methodological approaches used in waste management practice and provide a guidance on how game theory differs from, and is complementary to, the primary decision-making tools available where cooperation is a feature too often missing. This review seeks to justify the development of game theory to complement waste management decision-making methods in civil engineering, where resource consumption and waste management is often voluminous. An application of game theory to a waste management example illustrates that this methodological approach is of complementary value. The contribution of this study to circular economy and solid waste agendas is to emphasise the capability of game theory to help facilitate conflict resolution, competition, and stakeholder consensus when capturing multiple (sometimes conflicting) values in line with circular economy principles.


Subject(s)
Game Theory , Waste Management , Decision Making , Economic Development , Solid Waste
2.
Bull Entomol Res ; 103(6): 675-82, 2013 Dec.
Article in English | MEDLINE | ID: mdl-23842030

ABSTRACT

Wheat bulb fly (WBF) larvae use chemotaxis to orientate towards host-plant root exudates. This study aimed to investigate the role of the primary plant metabolite carbon dioxide (CO2) in host-plant location by WBF. Arena based behavioural experiments were used to identify whether CO2 induced chemotaxis (directional movement in response to a chemical stimulus) or kinesis (non-directional movement in response to a stimulus) from WBF larvae. No chemotactic response was observed when larvae were presented to a point source of CO2. However, elevated levels of CO2 induced kinesis, with both track length and tortuosity (number of twists and turns in the movement path) increasing at elevated CO2 levels of 1000-2000 ppm, demonstrating increased searching behaviour. Soil emission of CO2 was quantified to compare soil levels with those identified as eliciting behavioural effects on the larvae. Samples removed from soil gave a mean CO2 concentration of 557 (±46) ppm, which is lower than the lowest concentration of CO2 found to induce a behavioural response and higher than the lowest CO2 concentration tested, which was found not to alter behaviour. It is proposed that increased CO2 concentrations in the soil act as a behavioural trigger, inducing intensive searching of an area by WBF larvae. This increases the likelihood of finding more host-specific identifiers, such as secondary metabolites when near a potential host-plant.


Subject(s)
Behavior, Animal/drug effects , Carbon Dioxide/pharmacology , Diptera/drug effects , Animals , Carbon Dioxide/analysis , Carbon Dioxide/metabolism , Larva/drug effects , Seedlings/metabolism , Soil/chemistry
3.
Bull Entomol Res ; 103(3): 261-8, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23340388

ABSTRACT

Wheat bulb fly (WBF, Delia coarctata, Fallén, Diptera: Anthomyiidae) is a pest of commercial importance in wheat, barley and rye, with attacked crops failing to produce full potential yields. Females do not oviposit in association with a host-plant; therefore, prompt location of a suitable host is critical to the survival of the newly hatched larvae. The objective of this study was to conduct choice test bioassays to assess the attraction of WBF larvae to specific chemical constituents of WBF host-plant root exudates, the hydroxamic acids DIMBOA (2,4-dihydroxy-7-methoxy-1,4-benzoxazin-3-one) and MBOA (6-methoxy-benzoxazolin-2-one). The larval response to four concentrations of each test compound was assessed in arena bioassays. Analysis using a Rayleigh test of uniformity of the final resting positions of larvae in response to these chemicals indicated attraction. These results go some way to explaining the mechanisms by which WBF larvae locate host plants, giving the potential to develop semiochemical based control strategies.


Subject(s)
Chemotaxis/drug effects , Diptera/metabolism , Hydroxamic Acids/metabolism , Pheromones/metabolism , Plant Exudates/metabolism , Plant Roots/chemistry , Poaceae/parasitology , Animals , Diptera/drug effects , Larva/drug effects , Larva/metabolism , Poaceae/chemistry , United Kingdom
4.
Phlebology ; 27(8): 430-3, 2012 Dec.
Article in English | MEDLINE | ID: mdl-22368193

ABSTRACT

In the recent past, eight cases of transient ischaemic attack or cerebral vascular accident related to foam sclerotherapy have been reported. The following case is reported to add to the world clinical experience and raises the concern that foam sclerotherapy should continue to be evaluated and reported rigorously to establish the incidence of potentially devastating complications. While waiting for clinical studies to further establish best practice in this area of treatment, it may be in our patients' best interests to reserve the option of foaming sclerosants for selected rather than routine cases of venous insufficiency.


Subject(s)
Intracranial Embolism/chemically induced , Sclerosing Solutions/adverse effects , Sclerotherapy/adverse effects , Varicose Veins/therapy , Venous Insufficiency/therapy , Adult , Female , Humans , Sclerosing Solutions/administration & dosage
5.
Article in English | MEDLINE | ID: mdl-23801667

ABSTRACT

The neural crest is a transient population of multipotent and migratory cells unique to vertebrate embryos. Initially derived from the borders of the neural plate, these cells undergo an epithelial to mesenchymal transition to leave the central nervous system, migrate extensively in the periphery, and differentiate into numerous diverse derivatives. These include but are not limited to craniofacial cartilage, pigment cells, and peripheral neurons and glia. Attractive for their similarities to stem cells and metastatic cancer cells, neural crest cells are a popular model system for studying cell/tissue interactions and signaling factors that influence cell fate decisions and lineage transitions. In this review, we discuss the mechanisms required for neural crest formation in various vertebrate species, focusing on the importance of signaling factors from adjacent tissues and conserved gene regulatory interactions, which are required for induction and specification of the ectodermal tissue that will become neural crest.


Subject(s)
Neural Crest/metabolism , Transcription Factors/metabolism , Animals , Bone Morphogenetic Proteins/metabolism , Chromatin Assembly and Disassembly , Epithelial-Mesenchymal Transition , Fibroblast Growth Factors/metabolism , Gene Regulatory Networks , Signal Transduction , Wnt Proteins/metabolism
7.
Biotechnol Appl Biochem ; 31(3): 219-24, 2000 06.
Article in English | MEDLINE | ID: mdl-10814592

ABSTRACT

The instability of RNA in solutions during storage and travel is an impediment to its utilization in routine diagnostics. A robust and simple approach to the problem of RNA protection and processing is offered by storage of RNA desiccated with processing procedures that do not solublize the RNA until the beginning of reverse transcription. The feasibility of this general approach was tested with coxsackievirus B4 (CVB-4) from blood or culture fluid held on a storage and transport medium (FTA(R)) and analysed by reverse transcriptase PCR (RT-PCR) without removing the RNA from the FTA(R) until reverse transcription. Phase-trapping techniques based on water-miscible solvents such as ethanol or phenol were compared with simple buffers and concentrated lithium chloride solutions. RT-PCR detection of viral RNA reached a sensitivity of approximately 0.1 fg, which is comparable with other non-nested PCR techniques. Whole blood as a virus vehicle significantly interfered with CVB-4 detection, but to an acceptable degree. Desiccation-storage of the RNA of CVB-4 appears to be unaffected by weeks on the storage medium under ambient conditions. These characteristics indicate that this approach forms a credible developmental base for RNA-based pathogen diagnostics with particular application to the problem of transporting potentially infectious body fluids to a centralized laboratory for analysis.


Subject(s)
RNA, Viral/analysis , RNA, Viral/genetics , Reverse Transcriptase Polymerase Chain Reaction/methods , Specimen Handling/methods , Blood Specimen Collection/instrumentation , Blood Specimen Collection/methods , DNA Primers , Enterovirus B, Human/genetics , Enterovirus B, Human/isolation & purification , Humans , RNA, Viral/chemistry , RNA-Directed DNA Polymerase/chemistry , RNA-Directed DNA Polymerase/metabolism , Sensitivity and Specificity , Specimen Handling/instrumentation
8.
IEEE Trans Neural Netw ; 5(3): 424-35, 1994.
Article in English | MEDLINE | ID: mdl-18267809

ABSTRACT

Proposes a fundamental construct, called the microcircuit, that constitutes the basic building block of an associative memory model, the muAM. The microcircuit's structure is based on cerebellar interneuron connectivity patterns. Overlapping microcircuit activity is used to describe muAM memory operations, and quantitative expressions for the memory's storage and recall behavior are given. Measures of the memory's fidelity are derived and an analysis, including simulation results, of the model's recall behavior is given.

9.
Can J Surg ; 34(3): 283-6, 1991 Jun.
Article in English | MEDLINE | ID: mdl-2054761

ABSTRACT

The authors examined the patterns of injury and death rates of patients involved in vehicle-related accidents who were admitted to the Regional Trauma Unit of Sunnybrook Health Science Centre in Toronto. Information was collected prospectively over a 36-month period. The subjects were placed in one of three mechanism-of-injury categories: four-wheel passenger vehicles, motorcycles and pedestrians. The patterns of injury were classified as primarily to the craniofacial and neck area, the torso, the extremities or to multiple regions. There were 815 patients who were involved in vehicle-related crashes and who suffered moderate to severe injuries (at least one region scoring more than 3 on the abbreviated injury scale). The death rate was 13% overall but was 21% in the group receiving multiple injuries. By mechanism of injury the death rates were: pedestrian group 20%, motorcycle group 18% and passenger-vehicle group 11% (p less than 0.01, chi 2 analysis). There was no difference in the mean injury severity score among the mechanism of injury groups. A higher proportion of the passenger-vehicle group sustained isolated craniofacial and torso injuries, and the pedestrian and motorcycle groups sustained more extremity injuries (p less than 0.001, chi 2 analysis). The results reveal a clear association between mechanism of injury and the patterns of injury observed.


Subject(s)
Accidents, Traffic/statistics & numerical data , Injury Severity Score , Wounds and Injuries/classification , Accidents, Traffic/mortality , Adult , Automobiles , Female , Humans , Male , Motorcycles , Prospective Studies , Trauma Centers
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