We propose to investigate the consequences of labor outmigration on agricultural productivity in a poor agricultural country persistently facing food security problems. We aim to answer three high-priority scientific and policy questions: To what extent (a) Does labor outmigration influence (i) agricultural productivity, (ii) women's participation in farming, and (iii) exit from farming? (b) Do remittances influence (i) farm technology use, (ii) women's participation in farming, and (iii) exit from farming? (c) Do farm technology use and exit from farming influence subsequent outmigration? With an estimated 214 million people l--mostly from poor agricultural regions to more industrialized countries-international migration is a key concern in scholarly and policy arenas. This unprecedented phenomenon has wide-ranging consequences both for migrant-sending and receiving locations. This study focuses on one specific, but crucial consequence - the impact of labor outmigration on agricultural productivity in migrant-sending areas. As the agriculture productivity in poor subsistence economies is closely connected with one of the world's epidemic problems: food security. FAO estimated about 870 million people were undernourished in the period 2010-12. The vast majority of these - 852 million live in developing countries. Thus, increased agricultural productivity in poor countries is a key tool for alleviating this problem. This proposed project aims to better understand the relationship between labor outmigration and agriculture, providing crucial information for scientific and policy development of food security concerns. Understanding the link between outmigration and agriculture is complicated by the fact that migration does not happen randomly. Additionally, changes in agricultural practices and migration are likely to influence each other. Thus, the empirical demands for adjudicating potential reciprocal relationships are high, limiting the ability of previous research to speak to these questions. To address this complication, we will leverage the Chitwan Valley Family Study (CVFS), a case control comparison design at the community level with a 15-year panel study of a stratified systematic sample of communities, households, and individuals in Nepal. This unusual panel study enables us to address the non-random selection of individuals into migration. Furthermore, the case control design is particularly powerful for controlling macro-level effects (e.g. climate, prices, and policies) to detect the effect of change and variation in the phenomena of interest: farm labor loss, remittances, farm technology use, agricultural productivity, and women's participation in farming. Despite the wealth of panel data, answering our specific questions requires a modest level of new data collection. Our proposed panel measurement will involve multi-mode mixed methods data collection with appropriate temporal order and timing precision necessary to assess the relationships31. This study will generate high quality scientific outcomes that will be widely disseminated around the world. These outcomes are (i) comprehensive panel data with potential to address perplexing methodological problems; and (ii) empirical evidence of the consequences of labor outmigration, agricultural productivity, and its interplay with gender. First the data will be made available through ICPSR and UK Data Service and publications through websites will be provided to broader audiences. Second, the findings will be disseminated among the scientific communities through presentations at national and international conferences and publication of scientific articles, research briefs, and policy briefs. Finally, our capacity building training will also enhance scientific and analytical capacity of faculty and scientists of host country institutions (AFU, NARC and others).

New manufacturing methods are required if we are to live sustainably on the earth. In the electronics industry there is enormous interest in the possibility of manufacturing devices using organic materials: they can be manufactured sustainably from earth-abundant resources at energy costs that are typically significantly less than those associated with the production of equivalent inorganic materials. Electronic devices based on organic components are now readily available in the high street. For example, organic light-emitting diodes are used to produce the displays used in some high-end TV sets and in smartphones (e.g. iPhone X). However, a fundamental problem prevents the realisation of the full potential of organic materials in electronic devices. When light is absorbed by molecular semiconductors, it causes the creation of excitons - pairs of opposite charges - that carry excitation through the device. However, the excitons in organic materials recombine and cancel themselves out extremely rapidly - they can only move short distances through the material. This fundamental obstacle limits the application of organic materials in consumer electronics and also in many other areas of technology - in quantum communications, photocatalysis and sensor technologies. We propose an entirely new approach to solving this problem that is based on combining molecular designs inspired by photosynthetic mechanisms with nanostructured materials to produce surprising and intriguing quantum optical effects that mix the properties of light and matter. On breadboards, threaded mounts hold optical components relative to one another so that rays of light can be directed through an optical system. This proposal also aims to design breadboards, but of a very different kind. The smallest components will be single chromophores (light absorbing molecules), held at fixed arrangements in space by minimal building blocks called antenna complexes, whose structures are inspired by those of proteins involved in photosynthesis. Antenna complexes are designed and made from scratch using synthetic biology and chemistry so that transfer of energy can be controlled by programming the antenna structure. Instead of using threaded mounts, we will organise these components by attachment to reactive chemical groups formed on solid surfaces by nanolithography. In these excitonic films, we will develop design rules for efficient long-range transport. In conventional breadboards, light travels in straight lines between components. However, we will use the phenomenon of strong light-matter coupling to achieve entirely different types of energy transfer. In strong coupling, a localised plasmon resonance (an light mode confined to the surface of a nanoparticle) is hybridised with molecular excitons to create new states called plexcitons that combine the properties of light and matter. We will create plexcitonic complexes, in each of which an array of as many as a thousand chromophores is strongly coupled to a plasmon mode. In these plexcitonic complexes, the coupling is collective - all the chromophores couple to the plasmon simultaneously, and so the rules of energy transfer are completely re-written. Energy is no longer transferred via a series of linear hopping steps (as it is in organic semiconductors), but is delocalised instantaneously across the entire structure - many orders of magnitude further than is possible in conventional organic semiconductors. By designing these plexcitonic complexes from scratch we aim to create entirely new properties. The resulting materials are fully programmable from the scale of single chromophores to macroscopic structures. By combining biologically-inspired design with strong light-matter coupling we will create many new kinds of functional structures, including new medical sensors, 'plexcitonic circuits', and quantum optical films suitable for many applications, using low-cost, environmentally benign methods.

The development of radiometric geochronology is one of the greatest triumphs of 20th century geoscience. Geochronology underpins the study of Earth history and puts fundamental constraints on the rate of biological evolution. Tremendous resources are invested in the development of sophisticated mass spectrometers capable of measuring isotopic ratios with ever increasing resolution and sensitivity. Unfortunately, the statistical treatment of mass spectrometer data has not kept up with these hardware developments and this undermines the reliability of radiometric geochronology. This proposal aims to create a 'software revolution' in geochronology, by building an internally consistent ecosystem of computer programs to account for inter-sample error correlations. These have a first order effect on the precision and accuracy of geochronology but are largely ignored by current geochronological data processing protocols. The proposed software will modify existing data reduction platforms and create entirely new ones. It will implement a data exchange format to combine datasets from multiple chronometers together whilst keeping track of the correlated uncertainties between them. The new algorithms will be applied to five important geological problems. 1. The age of the Solar System is presently constrained to 4567.30 +/- 0.16 Ma using primitive meteorites. The meteorite data are 'underdispersed' with respect to the analytical uncertainties. The presence of strong inter-sample error correlations is one likely culprit for this underdispersion. Accounting for these correlations will significantly improve the accuracy and precision of this iconic age estimate. 2. The Cretaceous-Palaeogene boundary marks the disappearance of the dinosaurs in the most notorious mass extinction of Earth history. We will re-evaluate the timing of critical events around this boundary using high precision 40Ar/39Ar geochronology. Preliminary results from other samples show that 40Ar/39Ar data are prone to strong (r^2 > 0.9) inter-sample error correlations, and that these have a first order effect on the precision and accuracy of weighted mean age estimates. A sensitivity test indicates that this may change the timing of the mass extinction by up to 200ka. 3. The 'Taung Child' is a famous hominin fossil that was discovered in a South African cave in 1924. It is considered to be the world's first Australopithecine, but has not yet been dated. We have a good unpublished U-Pb age of 1.99 +/- 0.05 Ma from a tufa collected above the hominid, and an imprecise upper age limit of 1.4 +/- 2.7 Ma on a calcrete deposit below it. Applying the new algorithms to the latter date will greatly improve its precision. This will be further improved with additional measurements, in time for the 100th anniversary of the Taung Child's discovery. 4. Depth profiling of the U-Pb ages in rutile and apatite provides an exciting new way to constrain the thermal evolution of lower crustal rocks. However, the laser ablation data used for this research are prone to strong error correlations that are not accounted for by current data reduction protocols. These protocols will be revised using the new software, permitting better resolution of the inferred t-T paths. (5) Radiogenic noble gases such as 40Ar (from 40K), 4He (from U, Th and Sm), and 129Xe (from 129I) are lost by volume diffusion at high temperatures. The revised regression algorithms implemented by the research programme will be applied to step-heating 'Arrhenius' experiments. This will improve the calculation of diffusion coefficients for these gas species, resulting in further improvement of (noble gas) thermochronology.

One of the most important outcomes of the last quarter-century of synthetic biology is the recognition that the biopolymers that have been delivered to us by 4 billion years of biological evolution are not the only molecules that might support genetics, inheritance, evolution, and catalysis. Developing new biopolymers and characterizing their properties in living organisms not only has significance for testing our ideas about the functional optimization of the existing "molecules of life" but also opens new opportunities in biotechnology. Such work also permits insights into questions of the uniqueness of terrean biology and whether life in other parts of the universe could be constructed using alternate chemistries. Considering just DNA and RNA (collectively xNA), it is now clear that the four distinct "standard" building blocks (A, G, C, T and its equivalent U) for xNA do not exhaust the constraints imposed by the two rules guiding Watson-Crick pairing in natural nucleic acids. For example, the number of nucleobase pairs can be increased from two to six by merely rearranging hydrogen bond donor and acceptor groups. Efforts to implement this observation in practice using chemical synthesis, have (so far) led to two "generations" of novel heterocycles that can be incorporated into precursors suitable for use in automated xNA synthesis, thereby yielding artificially expanded genetic information systems (AEGIS). Although exploiting altered patterns of hydrogen bonding to obtain novel nucleobase pairs that are (in principle) "orthogonal" to A:T and G:C appears straightforward, the practical realization of these ideas has proven surprisingly problematic. For example, some potential heterocycles have highly populated tautomeric forms with altered hydrogen bonding patterns; these can base pair with standard nucleobases in either duplex DNA or within the active sites of polymerases, thereby giving rise to unanticipated mutations or the loss of the AEGIS nucleobases during replication. Being able to predict tautomer populations in solution or within enzyme active sites prior to chemical synthesis would be a significant step in improving the efficiency with which new nucleobase pairs can be discovered. Even were these "design" problems to be resolved, little is known about how the incorporation of these non-natural nucleobases into xNA affects the conformational preferences and dynamical properties of these complex molecules, which are fundamental to the interaction of "standard" xNA with proteins, such as polymerases, and transcription factors. We note that there has been a dearth of studies aimed at understanding how AEGIS nucleobases, which have altered electrostatic properties (dipole moments, charge distribution), might perturb xNA structure in both free solution and when bound within polymerase active sites. Finally, the validation of the force field parameters needed to model AEGIS nucleobases by, for example, comparing calculated free energies of interaction between xNA and proteins with experimental measurements has not yet been reported. Work in this project will therefore seek to address the problems outlined above by (i) developing and validating new computational methods for determining the populations of tautomeric forms of AEGIS nucleobases in water and in protein environments, and (ii) using advanced MD-based methods to understand how the incorporation of AEGIS nucleobase pairs affects the conformational and dynamical properties of duplex DNA and its interactions with DNA-binding proteins and polymerases. In particular, free energy perturbation methods will be used to study how replacing "standard" Watson-Crick bases by an AEGIS nucleobase pair changes the affinity of the DNA-binding domain of the human SETMAR transcription factor. The successful accomplishment of this aim will lay a foundation for obtaining novel endonucleases capable of cleaving AEGIS-containing duplex DNA.

Western Melanesia-including New Guinea-sits at the crossroads of Asia and Australia and is one of the most interesting, puzzling, and understudied hyperdiverse regions on Earth. Clarifying how tectonic movements have sundered or joined different Melanesian landforms in the past several million years is key to understanding the origins of this biotic diversity. The intent of this project is to elucidate how the diversity and evolutionary history of the five major geological landforms that comprise most of western Melanesia have impacted evolution of that region's biota and to identify those ancient insular landmasses critical in the origin of lineages that colonised and radiated across New Guinea, Australia, and/or insular Asia. To meet this goal, we will construct dated phylogenetic trees on a multitude of reptile and amphibian (herpetofauna) lineages having different dispersal abilities, times of origin, and natural histories that span the five major landmasses of western Melanesia. We will use the dates and relationships recovered to identify areas and times of origin for each clade and trace their expansion to new regions. Cross-validation between these results and updated geological models will illuminate tectonic events that drove speciation and dispersal in the region. We use herpetofauna to address these questions because their variable but moderate trans-marine dispersal abilities allow them to better track geological history than do taxa having much greater (e.g., birds) or lesser (e.g., land snails) dispersal capabilities. This research will help to replace the outdated, unidirectional "out-of-New-Guinea" model for origins of Pacific biodiversity with a more dynamic and nuanced understanding that ancient, yet under-appreciated, land areas in Melanesia have long been important in shaping biotic evolution in the broader region.