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1.
Disasters ; 43(3): 686-708, 2019 Jul.
Article in English | MEDLINE | ID: mdl-31172577

ABSTRACT

The continuing incidence of disasters and their associated challenges has increased the demand for humanitarian logisticians. However, there is a dearth of research on their essential competencies. This paper proposes, therefore, a humanitarian logistics competency framework (HlCF) to assist with the professional development of humanitarian logisticians. In creating the HlCF, nine competency domains containing 29 specific competencies across four levels (entry to senior management) were identified. This study makes two key contributions to the literature: (i) it extends the discussion of competency frameworks in humanitarian logistics; and (ii) it presents a framework designed to support the human resource plans and practices of aid agencies. The HlCF allows not only individual humanitarian logisticians to develop the competencies necessary for career success, but also humanitarian organisations to map their own competency frameworks to a common standard. This will, in turn, facilitate workforce mobility and support the overall concept of a certified humanitarian logistics professional.


Subject(s)
Disasters , Professional Competence , Relief Work/organization & administration , Humans
2.
Plant Biotechnol J ; 14(2): 567-80, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26015295

ABSTRACT

In planta production of the bioplastic polyhydroxybutyrate (PHB) is one important way in which plant biotechnology can address environmental problems and emerging issues related to peak oil. However, high biomass C4 plants such as maize, switch grass and sugarcane develop adverse phenotypes including stunting, chlorosis and reduced biomass as PHB levels in leaves increase. In this study, we explore limitations to PHB accumulation in sugarcane chloroplasts using a systems biology approach, coupled with a metabolic model of C4 photosynthesis. Decreased assimilation was evident in high PHB-producing sugarcane plants, which also showed a dramatic decrease in sucrose and starch content of leaves. A subtle decrease in the C/N ratio was found which was not associated with a decrease in total protein content. An increase in amino acids used for nitrogen recapture was also observed. Based on the accumulation of substrates of ATP-dependent reactions, we hypothesized ATP starvation in bundle sheath chloroplasts. This was supported by mRNA differential expression patterns. The disruption in ATP supply in bundle sheath cells appears to be linked to the physical presence of the PHB polymer which may disrupt photosynthesis by scattering photosynthetically active radiation and/or physically disrupting thylakoid membranes.


Subject(s)
Carbon/metabolism , Metabolic Engineering/methods , Models, Biological , Plant Leaves/metabolism , Saccharum/metabolism , Systems Biology/methods , Chloroplasts/metabolism , Chloroplasts/ultrastructure , Circadian Rhythm , Gene Expression Regulation, Plant , Hydroxybutyrates/metabolism , Metabolome , Nitrogen/metabolism , Photosynthesis , Plants, Genetically Modified , RNA, Messenger/genetics , RNA, Messenger/metabolism , Saccharum/genetics
3.
Plant Biotechnol J ; 13(5): 700-7, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25532451

ABSTRACT

Engineering the production of polyhydroxyalkanoates (PHAs) into high biomass bioenergy crops has the potential to provide a sustainable supply of bioplastics and energy from a single plant feedstock. One of the major challenges in engineering C4 plants for the production of poly[(R)-3-hydroxybutyrate] (PHB) is the significantly lower level of polymer produced in the chloroplasts of mesophyll (M) cells compared to bundle sheath (BS) cells, thereby limiting the full PHB yield-potential of the plant. In this study, we provide evidence that the access to substrate for PHB synthesis may limit polymer production in M chloroplasts. Production of PHB in M cells of sugarcane is significantly increased by replacing ß-ketothiolase, the first enzyme in the bacterial PHA pathway, with acetoacetyl-CoA synthase. This novel pathway enabled the production of PHB reaching an average of 6.3% of the dry weight of total leaf biomass, with levels ranging from 3.6 to 11.8% of the dry weight (DW) of individual leaves. These yields are more than twice the level reported in PHB-producing sugarcane containing the ß-ketothiolase and illustrate the importance of producing polymer in mesophyll plastids to maximize yield. The molecular weight of the polymer produced was greater than 2 × 10(6)  Da. These results are a major step forward in engineering a high biomass C4 grass for the commercial production of PHB.


Subject(s)
Acetyl-CoA C-Acyltransferase/metabolism , Hydroxybutyrates/metabolism , Polyesters/metabolism , Polyhydroxyalkanoates/metabolism , Saccharum/enzymology , Acetyl-CoA C-Acyltransferase/genetics , Acyl Coenzyme A/metabolism , Biomass , Biosynthetic Pathways , Chloroplasts/genetics , Crops, Agricultural , Mesophyll Cells/metabolism , Plant Leaves/enzymology , Plant Leaves/genetics , Plant Leaves/growth & development , Plant Proteins/genetics , Plant Proteins/metabolism , Plants, Genetically Modified , Plastids/metabolism , Saccharum/genetics , Saccharum/growth & development
4.
Conserv Biol ; 28(5): 1167-77, 2014 Oct.
Article in English | MEDLINE | ID: mdl-24962114

ABSTRACT

Natural scientists are increasingly interested in social research because they recognize that conservation problems are commonly social problems. Interpreting social research, however, requires at least a basic understanding of the philosophical principles and theoretical assumptions of the discipline, which are embedded in the design of social research. Natural scientists who engage in social science but are unfamiliar with these principles and assumptions can misinterpret their results. We developed a guide to assist natural scientists in understanding the philosophical basis of social science to support the meaningful interpretation of social research outcomes. The 3 fundamental elements of research are ontology, what exists in the human world that researchers can acquire knowledge about; epistemology, how knowledge is created; and philosophical perspective, the philosophical orientation of the researcher that guides her or his action. Many elements of the guide also apply to the natural sciences. Natural scientists can use the guide to assist them in interpreting social science research to determine how the ontological position of the researcher can influence the nature of the research; how the epistemological position can be used to support the legitimacy of different types of knowledge; and how philosophical perspective can shape the researcher's choice of methods and affect interpretation, communication, and application of results. The use of this guide can also support and promote the effective integration of the natural and social sciences to generate more insightful and relevant conservation research outcomes.


Subject(s)
Conservation of Natural Resources , Philosophy , Social Sciences , Research Design
5.
Plant Biotechnol J ; 11(9): 1146-51, 2013 Dec.
Article in English | MEDLINE | ID: mdl-24112832

ABSTRACT

Polyhydroxybutyrate (PHB) is a naturally occurring bacterial polymer that can be used as a biodegradable replacement for some petrochemical-derived plastics. Polyhydroxybutyrate is produced commercially by fermentation, but to reduce production costs, efforts are underway to produce it in engineered plants, including sugarcane. However, PHB levels in this high-biomass crop are not yet commercially viable. Chemical ripening with herbicides is a strategy used to enhance sucrose production in sugarcane and was investigated here as a tool to increase PHB production. Class A herbicides inhibit ACCase activity and thus reduce fatty acid biosynthesis, with which PHB production competes directly for substrate. Treatment of PHB-producing transgenic sugarcane plants with 100 µM of the class A herbicide fluazifop resulted in a fourfold increase in PHB content in the leaves, which peaked ten days post-treatment. The minimum effective concentration of herbicide required to maximize PHB production was 30 µM for fluazifop and 70 µM for butroxydim when applied to saturation. Application of a range of class A herbicides from the DIM and FOP groups consistently resulted in increased PHB yields, particularly in immature leaf tissue. Butroxydim or fluazifop treatment of mature transgenic sugarcane grown under glasshouse conditions increased the total leaf biomass yield of PHB by 50%-60%. Application of an ACCase inhibitor in the form of a class A herbicide to mature sugarcane plants prior to harvest is a promising strategy for improving overall PHB yield. Further testing is required on field-grown transgenic sugarcane to more precisely determine the effectiveness of this strategy.


Subject(s)
Acetyl-CoA Carboxylase/antagonists & inhibitors , Herbicides/pharmacology , Hydroxybutyrates/metabolism , Saccharum/enzymology , Acetyl-CoA Carboxylase/metabolism , Biomass , Gene Expression Regulation, Plant , Genetic Engineering , Plant Leaves/drug effects , Plant Leaves/enzymology , Plant Leaves/genetics , Plant Leaves/metabolism , Plants, Genetically Modified , Saccharum/drug effects , Saccharum/genetics , Saccharum/metabolism , Time Factors
6.
Public Underst Sci ; 21(5): 573-89, 2012 Jul.
Article in English | MEDLINE | ID: mdl-23823166

ABSTRACT

This paper explores the transfer and dissemination of knowledge between scientists, the volunteers who collect the knowledge and the communities which learn from it in order to implement change. The role of knowledge "stickiness" in the reduction of knowledge transfer is outlined. The characteristics of the knowledge and the situation combine to develop a range of factors, "stickiness predictors," which can deter knowledge transfer. These stickiness predictors are used to analyse data gathered from three qualitative cases, which were developed from both participant observation and semi-structured interviews studying the interactions between the scientists, volunteers and organisations. A reconsideration of the way that knowledge and knowledge transfer are being conceptualised by scientists is proposed, in order to enable "stickiness" factors to be recognised and managed, thereby increasing the potential for scientific literacy. A move towards a more broadly constituted community of practice is proposed.

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