Electron Transport in Two-Dimensional Molybdenum Disulphide

This thesis will describe the experimental details used to make two-dimensional field-effect transistors using monolayer and bilayer transition metal dichalcogenides, including the fabrication of new sample holders required to cross between multiple experimental set-ups. Electron transport in these devices is measured at room temperature and at low temperature in a dilution refrigerator with a base temperature below 10 mK. Atomic force microscope lithography is explored as a technique for locally functionalising the surface of the device to create nano-features, with particular interest paid to the formation of quantum dots. Transport curves before and after lithography demonstrate the change in transport characteristics. A comprehensive study of device behaviour at room temperature is carried out. The effects of pumping and heating on the device are measured and discussed. Improvements in the transport occur from the removal of charge traps and the improved contact between the Ti/Au contact and the crystal. Low temperature (<10 mK) measurements of bilayer MoS2 devices show evidence of Coulomb blockade and the presence of small, unstable, naturally formed quantum dots. We suspect that interface states due to naturally occurring atomic defects in MoS2 which result in Fermi level pinning at room temperature are being probed here. The evolution of these states with magnetic field is measured, for devices positioned parallel and perpendicular to the magnetic field

Characterizing genetic diversity and creating novel gene pools in rice for trait dissection and gene function discovery

Rice diversity is the foundation for rice improvement programs. At IRRI, over 100,000 rice accessions are deposited, and intelligent use of this diversity can not only help solve current production problems but also create future production opportunities and tackle climate change challenges. To fully explore and utilize rice diversity, two ingredients are needed: 1 - the genetic blueprints of diverse rice accessions in use, 2 - plant populations with recombined genotypes allowing expression of phenotypic variation and discovery of new genes/QTLs for use in breeding programs. Sequencing of the genomes &#x26; obtaining SNP genotypes of many rice accessions is feasible due to decreasing cost of advanced DNA sequencing technologies. Coupled with the creation of populations suitable for trait dissection / phenotyping, discovery of gene functions and allelic variations causal to important agronomic traits becomes possible. This in turn will provide rich biological evidences to the rice/cereal crop genome annotation community

International agreements and the plant genetics research community: A guide to practice

Plant genetic resources (PGR), including collections held in national and international gene banks, provide access to a wide array of genetic diversity and are critical to genomics research, conservation efforts, and applied breeding. Yet, there is a general lack of awareness in the research community about the rules and treaties that govern the use of PGR, about access and benefit sharing obligations contained in international treaties and/or national laws, and about how best to comply with potentially applicable requirements. This article provides a brief history and overview of three key international agreements, namely the Convention on Biological Diversity, the Nagoya Protocol, and the International Treaty on Plant Genetic Resources for Food and Agriculture, which collectively address responsibilities and obligations related to the use of much of the world’s PGR. By highlighting the coverage and key considerations of each agreement, the article provides a guide for those who use PGR in plant genetics research to better understand when and how international agreements apply, and—where the rules are unclear—to suggest best practices for compliance with existing agreements

Sensitivity of magnetic properties to chemical pressure in lanthanide garnets Ln3A2X3O12, Ln = Gd, Tb, Dy, Ho, A = Ga, Sc, In, Te, X = Ga, Al, Li

A systematic study of the structural and magnetic properties of three-dimensionally frustrated lanthanide garnets Ln3A2X3O12, Ln = Gd, Tb, Dy, Ho, A = Ga, Sc, In, Te, X = Ga, Al, Li is presented. Garnets with Ln = Gd show magnetic behaviour consistent with isotropic Gd3+ spins; no magnetic ordering is observed for T ≥ 0.4 K. Magnetic ordering features are seen for garnets with Ln = Tb, Dy, Ho in the temperature range 0.4 < T < 2.5 K, however the nature of the magnetic ordering varies for the different Ln as well as for different combinations of A and X. The changes in magnetic behaviour can be explained by tuning of the magnetic interactions and changes in the single-ion anisotropy. The change in magnetic entropy is evaluated from isothermal magnetisation measurements to characterise the magnetocaloric effect in these materials. Among the Gd garnets, the maximum change in magnetic entropy per mole (15.45 J K-1 molGd-1) is observed for Gd3Sc2Ga3O12 at 2 K, in a field of 9 T. The performance of Dy3Ga5O12 as a magnetocaloric material surpasses the other garnets with Ln = Tb, Dy, Ho.Winton Programme for the Physics of Sustainability, Advanced Materials Characterisation Suite, funded by EPSRC Strategic Equipment Grant EP1M0005241

Implications potentielles de l’utilisation de l’information génétique numérique sur les ressources génétiques sur les trois objectifs de la Convention sur la diversité biologique. Document soumis par le CGIAR au Secrétariat de la Convention sur la diversité biologique

This report has been submitted by CGIAR in response to an invitation issued by the Secretary of the Convention on Biological Diversity (CBD) calling on “relevant organizations and stakeholders to submit views and relevant information on any potential implications of the use of digital sequence information on genetic resources for the three objectives of the Convention” as input to the "Meeting of the Ad Hoc Technical Expert Group on Digital Sequence Information on Genetic Resources", 13 - 16 February 2018, Montreal, Canada. CGIAR experience to date confirms that digital genomic sequence data can play important roles in the management and sustainable use of biological diversity and in the sharing of benefits associated with the use of that diversity. Technological capacities to generate genomic sequence data have accelerated faster than capacities to enable practical use of this information. Relatively small investments in the initial generation of genomic sequences, must then be coupled with significantly larger investments to comparatively analyse genomic sequences, to link genetic variability to useful phenotypic traits or performance, to ‘optimize’ those traits, and ultimately, to develop new crop varieties for release and use in farmers’ fields. CGIAR underscores the importance of capacity building for developing country research and development organizations to generate and use genomic sequence information as part of their own conservation and crop improvement programs, and to be able to participate on equal footing in internationally coordinated and funded research and development programs. The most important benefit to be shared from the use of genomic sequence information in agricultural research and development and plant breeding is improved food and livelihood security. Other non-monetary benefits are farmers’ improved access to technologies, enhanced institutional capacities of developing country research organizations, shared research results, and local and regional economic development

Using genomic sequence information to increase conservation and sustainable use of crop diversity and benefit-sharing

This article describes how CGIAR centers and partners are using genomic sequence information to promote the conservation and sustainable use of crop genetic diversity, and to generate and share benefits derived from those uses. The article highlights combined institutional, and benefit-sharing-related challenges that need to be addressed to support expanded use of digital sequence information in agricultural research and developmen

Potential implications of the use of digital sequence information on genetic resources for the three objectives of the Convention on Biological Diversity. A submission from CGIAR to the Secretary of the Convention on Biological Diversity (CBD)

This report has been submitted by CGIAR in response to an invitation issued by the Secretary of the Convention on Biological Diversity (CBD) calling on “relevant organizations and stakeholders to submit views and relevant information on any potential implications of the use of digital sequence information on genetic resources for the three objectives of the Convention” as input to the "Meeting of the Ad Hoc Technical Expert Group on Digital Sequence Information on Genetic Resources", 13 - 16 February 2018, Montreal, Canada. CGIAR experience to date confirms that digital genomic sequence data can play important roles in the management and sustainable use of biological diversity and in the sharing of benefits associated with the use of that diversity. Technological capacities to generate genomic sequence data have accelerated faster than capacities to enable practical use of this information. Relatively small investments in the initial generation of genomic sequences, must then be coupled with significantly larger investments to comparatively analyse genomic sequences, to link genetic variability to useful phenotypic traits or performance, to ‘optimize’ those traits, and ultimately, to develop new crop varieties for release and use in farmers’ fields. CGIAR underscores the importance of capacity building for developing country research and development organizations to generate and use genomic sequence information as part of their own conservation and crop improvement programs, and to be able to participate on equal footing in internationally coordinated and funded research and development programs. The most important benefit to be shared from the use of genomic sequence information in agricultural research and development and plant breeding is improved food and livelihood security. Other non-monetary benefits are farmers’ improved access to technologies, enhanced institutional capacities of developing country research organizations, shared research results, and local and regional economic development

Posibles repercusiones del uso de la información digital sobre secuencias de recursos genéticos para los tres objetivos del Convenio sobre la Diversidad Biológica. Informe del CGIAR presentado ante la Secretaría del Convenio sobre la Diversidad Biológica

This report has been submitted by CGIAR in response to an invitation issued by the Secretary of the Convention on Biological Diversity (CBD) calling on “relevant organizations and stakeholders to submit views and relevant information on any potential implications of the use of digital sequence information on genetic resources for the three objectives of the Convention” as input to the "Meeting of the Ad Hoc Technical Expert Group on Digital Sequence Information on Genetic Resources", 13 - 16 February 2018, Montreal, Canada. CGIAR experience to date confirms that digital genomic sequence data can play important roles in the management and sustainable use of biological diversity and in the sharing of benefits associated with the use of that diversity. Technological capacities to generate genomic sequence data have accelerated faster than capacities to enable practical use of this information. Relatively small investments in the initial generation of genomic sequences, must then be coupled with significantly larger investments to comparatively analyse genomic sequences, to link genetic variability to useful phenotypic traits or performance, to ‘optimize’ those traits, and ultimately, to develop new crop varieties for release and use in farmers’ fields. CGIAR underscores the importance of capacity building for developing country research and development organizations to generate and use genomic sequence information as part of their own conservation and crop improvement programs, and to be able to participate on equal footing in internationally coordinated and funded research and development programs. The most important benefit to be shared from the use of genomic sequence information in agricultural research and development and plant breeding is improved food and livelihood security. Other non-monetary benefits are farmers’ improved access to technologies, enhanced institutional capacities of developing country research organizations, shared research results, and local and regional economic development