Higher education, equality & ethnicity:the attainment gap – what should we be doing?

This brief paper draws upon part of the findings of a HEA Sponsored evaluation of work conducted in 8 Universities across UK aimed at addressing the attainment gap between BME and White students. Following a grounded theory approach, semi-structured interviews with staff at each of the institutions were analysed and three main themes identified: Organisational Sensitivities: Language: and, Ownership. This paper provides a brief discussion of the issues identifying two areas where positive change is needed in institutional practice. The conclusion highlights the complexities of the underlying issues impacting and shaping the Attainment Gap before reaffirming the need to identify and evaluate which interventions are most likely to be transferable across the Sector so as to address the issues and thus enhance the experiences of all students.

Bridging the Scale Gap from Leaf to Canopy in Biosphere-Atmosphere Gas and Particle Exchanges

Terrestrial ecosystems, occupying more than 25% of the Earth's surface, can serve as

`biological valves' in regulating the anthropogenic emissions of atmospheric aerosol

particles and greenhouse gases (GHGs) as responses to their surrounding environments.

While the signicance of quantifying the exchange rates of GHGs and atmospheric

aerosol particles between the terrestrial biosphere and the atmosphere is

hardly questioned in many scientic elds, the progress in improving model predictability,

data interpretation or the combination of the two remains impeded by

the lack of precise framework elucidating their dynamic transport processes over a

wide range of spatiotemporal scales. The diculty in developing prognostic modeling

tools to quantify the source or sink strength of these atmospheric substances

can be further magnied by the fact that the climate system is also sensitive to the

feedback from terrestrial ecosystems forming the so-called `feedback cycle'. Hence,

the emergent need is to reduce uncertainties when assessing this complex and dynamic

feedback cycle that is necessary to support the decisions of mitigation and

adaptation policies associated with human activities (e.g., anthropogenic emission

controls and land use managements) under current and future climate regimes.

With the goal to improve the predictions for the biosphere-atmosphere exchange

of biologically active gases and atmospheric aerosol particles, the main focus of this

dissertation is on revising and up-scaling the biotic and abiotic transport processes

from leaf to canopy scales. The validity of previous modeling studies in determining

iv

the exchange rate of gases and particles is evaluated with detailed descriptions of their

limitations. Mechanistic-based modeling approaches along with empirical studies

across dierent scales are employed to rene the mathematical descriptions of surface

conductance responsible for gas and particle exchanges as commonly adopted by all

operational models. Specically, how variation in horizontal leaf area density within

the vegetated medium, leaf size and leaf microroughness impact the aerodynamic attributes

and thereby the ultrane particle collection eciency at the leaf/branch scale

is explored using wind tunnel experiments with interpretations by a porous media

model and a scaling analysis. A multi-layered and size-resolved second-order closure

model combined with particle

uxes and concentration measurements within and

above a forest is used to explore the particle transport processes within the canopy

sub-layer and the partitioning of particle deposition onto canopy medium and forest

oor. For gases, a modeling framework accounting for the leaf-level boundary layer

eects on the stomatal pathway for gas exchange is proposed and combined with sap

ux measurements in a wind tunnel to assess how leaf-level transpiration varies with

increasing wind speed. How exogenous environmental conditions and endogenous

soil-root-stem-leaf hydraulic and eco-physiological properties impact the above- and

below-ground water dynamics in the soil-plant system and shape plant responses

to droughts is assessed by a porous media model that accommodates the transient

water

ow within the plant vascular system and is coupled with the aforementioned

leaf-level gas exchange model and soil-root interaction model. It should be noted

that tackling all aspects of potential issues causing uncertainties in forecasting the

feedback cycle between terrestrial ecosystem and the climate is unrealistic in a single

dissertation but further research questions and opportunities based on the foundation

derived from this dissertation are also brie

y discussed.

Développement et caractérisation de dérivés dipyrrométhène pour des applications dans le domaine du photovoltaïque

Ce projet de recherche mené en collaboration industrielle avec St-Jean Photochimie Inc. / PCAS Canada vise le développement et la caractérisation de dérivés dipyrrométhène pour des applications dans le domaine du photovoltaïque. La quête du récoltage des photons se situant dans le proche-infrarouge a été au centre des modifications structurales explorées afin d’augmenter l’efficacité de conversion des cellules solaires de type organique et à pigments photosensibles. Trois familles de composés intégrant le motif dipyrrométhène ont été synthétisées et caractérisées du point de vue spectroscopique, électrochimique, structural ainsi que par modélisation moléculaire afin d’établir des relations structures-propriétés. La première famille comporte six azadipyrrométhènes au potentiel de coordination tétradentate sur des centres métalliques. Le développement d’une nouvelle voie synthétique asymétrique combinée à l’utilisation d’une voie symétrique classique ont permis d’obtenir l’ensemble des combinaisons de substituants possibles sur les aryles proximaux incluant les noyaux 2-hydroxyphényle, 2-méthoxyphényle et 2- pyridyle. La modulation du maximum d’absorption dans le rouge a pu être faite entre 598 et 619 nm. De même, la présence de groupements méthoxyle ou hydroxyle augmente l’absorption dans le violet (~410 nm) tel que démontré par modélisation. La caractérisation électrochimique a montré que les dérivés tétradentates étaient en général moins stables aux processus redox que leur contre-parti bidentate. La deuxième famille comporte dix dérivés BODIPY fusionnés de façon asymétrique en position [b]. L’aryle proximal a été modifié de façon systématique afin de mieux comprendre l’impact des substituents riches en électron et de la fusion de cycles aromatiques. De plus, ces dérivés ont été mis en relation avec une vaste série de composés analogues. Les résultats empiriques ont montré que les propriétés optoélectroniques de la plateforme sont régies par le degré de communication électronique entre l’aryle proximal, le pyrrole sur lequel il est attaché et le noyau indolique adjacent à ce dernier. Les maximums d’absorption dans le rouge sont modulables entre 547 et 628 nm et la fluorescence des composés se situe dans le proche- infrarouge. L’un des composé s’est révélé souhaitable pour une utilisation en photovoltaïque ainsi qu’à titre de sonde à pH. La troisième famille comporte cinq complexes neutres de RuII basés sur des polypyridines et portant un ligand azadipyrrométhène cyclométalé. Les composés ont montré une forte absorption de photons dans la région de 600 à 800 nm (rouge à proche- infrarouge) et qui a pu être étendue au-delà de 1100 nm dans le cas des dérivés portant un ligand terpyridine. L’analyse des propriétés optoélectroniques de façon empirique et théorique a montré un impact significatif de la cyclométalation et ouvert la voie pour leur étude en tant que photosensibilisateurs en OPV et en DSSC. La capacité d’un des complexes à photo-injecter un électron dans la bande de conduction du semi-conducteur TiO2 a été démontré en collaboration avec le groupe du Pr Gerald J. Meyer à University of North Carolina at Chapel Hill, premier pas vers une utilisation dans les cellules solaires à pigments photosensibles. La stabilité des complexes en solution s’est toutefois avérée problématique et des pistes de solutions sont suggérées basées sur les connaissances acquises dans le cadre de cette thèse.

Application de méthodes ab initio à l'étude de polymères semi-conducteurs

Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.

Development of the Oxide Ion Conductor Na0.5Bi0.5TiO3 (NBT) for Solid Oxide Cells

Na0.5Bi0.5TiO3 (NBT) is a well-known lead-free piezoelectric material with potential to replace lead zirconate titanate (PZT),1 however high leakage conductivity for the material has been widely reported.2 Through a combination of Impedance Spectroscopy (IS), O2- ion transference (EMF) number experiments and O18 tracer diffusion measurements, combined with Time-of-flight Secondary Ion Mass Spectrometry (TOFSIMS), it was identified that this leakage conductivity was due to oxygen ion conductivity. The volatilization of bismuth during synthesis, causing oxygen vacancies, is believed to be responsible for the leakage conductivity.3 The oxide-ion conductivity, when doped with magnesium, exceeds that of yttria-stabilized zirconia (YSZ) at ~500 °C,3 making it a potential electrolyte material for Intermediate Temperature Solid Oxide Cells (ITSOCs). Figure 1 shows the comparison of bulk oxide ion conductivity between 2 at.% Mg-doped NBT and other known oxide ion conductors.

As part of the UK wide £5.7m 4CU project, research has concentrated on trying to develop NBT for use in Intermediate Temperature Solid Oxide Cells (ITSOCS). With the aim of achieving mixed ionic and electronic conduction, transition metals were chemically doped on to the Ti-site. A range of experimental techniques was used to characterize the materials aimed at investigating both conductivity and material structure (Scanning Electron Microscopy (SEM), IS, X-ray Photoelectron Spectroscopy (XPS) and X-ray Absorption Spectroscopy (XAS)). The potential for NBT as an ITSOC material, as well as the challenges of developing the material, will be discussed.

(1) Takenaka T. et al. Jpn. J. Appl. Phys 1999, 30, 2236.

(2) Hiruma Y. et al. J. Appl. Phys 2009, 105, 084112.

(3) Li. M. et al. Nature Materials 2013, 13, 31.

A Frequency-Dependent Equivalence Between Groove Gap Waveguide and Rectangular Waveguide

Recently gap waveguides have been shown as a potential alternative to conventional waveguides in the millimeter-wave band. Groove Gap Waveguide (GGW) has until now been studied though direct correspondence with rectangular waveguide with the same propagation channel dimensions. However there have been observed differences in the above cutoff propagation characteristics between these waveguide types. Furthermore, the behaviour of GGW below cutoff remains unknown. This work presents a discussion of below and above cutoff propagation characteristics, and introduces a simple model that explains observed GGW behavior and establishes its propagation characteristics.

Closing the Gap: Young People's Views on Learning at School

The UK has been criticised for its inequitable education system, as student outcomes are strongly linked to parental socio-economic status. Children and young people experiencing poverty are less likely than their better off peers to leave school with good grades, which can perpetuate disadvantage in later life. The attainment gap between children and young people experiencing poverty and their better off peers in the UK is widening, despite an increasing media and policy focus in this area. Poverty-related educational inequality is a complex area and there is no conclusive evidence in what works to reduce its effects. While there is a plethora of research on the impact of poverty on education, very little of it includes the voice of children and young people and/or the psychological impact of poverty on learning. The importance of hearing the views of children and young people is central to educational psychology, as is social justice and facilitating access to the curriculum for all students. The barriers presented by the experience of poverty to learning are thus vital for educational psychologists to address. This study used qualitative methods to explore the learning journey of Key Stage 3 (age 12-13) young people experiencing poverty in an English coastal borough. Questions from the Little Box of Big Questions 2 were used as a tool in semi-structured interviews, in addition to questions devised by the researcher. Young people discussed aspects of their lives that enabled them to learn at school, and aspects that presented barriers to learning. The research used Positive Psychology, taking a strengths based approach to explore the skills young people thought they brought to education, skills they would like to develop, and how they could be supported in this. The study has highlighted themes that, if addressed, could potentially raise the attainment of children and young people experiencing poverty.

Semi-automatic parallelisation of unstructured mesh codes

The availability of CFD software that can easily be used and produce high efficiency on a wide range of parallel computers is extremely limited. The investment and expertise required to parallelise a code can be enormous. In addition, the cost of supercomputers forces high utilisation to justify their purchase, requiring a wide range of software. To break this impasse, tools are urgently required to assist in the parallelisation process that dramatically reduce the parallelisation time but do not degrade the performance of the resulting parallel software. In this paper we discuss enhancements to the Computer Aided Parallelisation Tools (CAPTools) to assist in the parallelisation of complex unstructured mesh-based computational mechanics codes.

An IP capable data link layer protocol for narrow band half-duplex packet data radio networks

The wide adaptation of Internet Protocol (IP) as de facto protocol for most communication networks has established a need for developing IP capable data link layer protocol solutions for Machine to machine (M2M) and Internet of Things (IoT) networks. However, the wireless networks used for M2M and IoT applications usually lack the resources commonly associated with modern wireless communication networks. The existing IP capable data link layer solutions for wireless IoT networks provide the necessary overhead minimising and frame optimising features, but are often built to be compatible only with IPv6 and specific radio platforms. The objective of this thesis is to design IPv4 compatible data link layer for Netcontrol Oy's narrow band half-duplex packet data radio system. Based on extensive literature research, system modelling and solution concept testing, this thesis proposes the usage of tunslip protocol as the basis for the system data link layer protocol development. In addition to the functionality of tunslip, this thesis discusses the additional network, routing, compression, security and collision avoidance changes required to be made to the radio platform in order for it to be IP compatible while still being able to maintain the point-to-multipoint and multi-hop network characteristics. The data link layer design consists of the radio application, dynamic Maximum Transmission Unit (MTU) optimisation daemon and the tunslip interface. The proposed design uses tunslip for creating an IP capable data link protocol interface. The radio application receives data from tunslip and compresses the packets and uses the IP addressing information for radio network addressing and routing before forwarding the message to radio network. The dynamic MTU size optimisation daemon controls the tunslip interface maximum MTU size according to the link quality assessment calculated from the radio network diagnostic data received from the radio application. For determining the usability of tunslip as the basis for data link layer protocol, testing of the tunslip interface is conducted with both IEEE 802.15.4 radios and packet data radios. The test cases measure the radio network usability for User Datagram Protocol (UDP) based applications without applying any header or content compression. The test results for the packet data radios reveal that the typical success rate for packet reception through a single-hop link is above 99% with a round-trip-delay of 0.315s for 63B packets.

Développement et caractérisation de dérivés dipyrrométhène pour des applications dans le domaine du photovoltaïque

Ce projet de recherche mené en collaboration industrielle avec St-Jean Photochimie Inc. / PCAS Canada vise le développement et la caractérisation de dérivés dipyrrométhène pour des applications dans le domaine du photovoltaïque. La quête du récoltage des photons se situant dans le proche-infrarouge a été au centre des modifications structurales explorées afin d’augmenter l’efficacité de conversion des cellules solaires de type organique et à pigments photosensibles. Trois familles de composés intégrant le motif dipyrrométhène ont été synthétisées et caractérisées du point de vue spectroscopique, électrochimique, structural ainsi que par modélisation moléculaire afin d’établir des relations structures-propriétés. La première famille comporte six azadipyrrométhènes au potentiel de coordination tétradentate sur des centres métalliques. Le développement d’une nouvelle voie synthétique asymétrique combinée à l’utilisation d’une voie symétrique classique ont permis d’obtenir l’ensemble des combinaisons de substituants possibles sur les aryles proximaux incluant les noyaux 2-hydroxyphényle, 2-méthoxyphényle et 2- pyridyle. La modulation du maximum d’absorption dans le rouge a pu être faite entre 598 et 619 nm. De même, la présence de groupements méthoxyle ou hydroxyle augmente l’absorption dans le violet (~410 nm) tel que démontré par modélisation. La caractérisation électrochimique a montré que les dérivés tétradentates étaient en général moins stables aux processus redox que leur contre-parti bidentate. La deuxième famille comporte dix dérivés BODIPY fusionnés de façon asymétrique en position [b]. L’aryle proximal a été modifié de façon systématique afin de mieux comprendre l’impact des substituents riches en électron et de la fusion de cycles aromatiques. De plus, ces dérivés ont été mis en relation avec une vaste série de composés analogues. Les résultats empiriques ont montré que les propriétés optoélectroniques de la plateforme sont régies par le degré de communication électronique entre l’aryle proximal, le pyrrole sur lequel il est attaché et le noyau indolique adjacent à ce dernier. Les maximums d’absorption dans le rouge sont modulables entre 547 et 628 nm et la fluorescence des composés se situe dans le proche- infrarouge. L’un des composé s’est révélé souhaitable pour une utilisation en photovoltaïque ainsi qu’à titre de sonde à pH. La troisième famille comporte cinq complexes neutres de RuII basés sur des polypyridines et portant un ligand azadipyrrométhène cyclométalé. Les composés ont montré une forte absorption de photons dans la région de 600 à 800 nm (rouge à proche- infrarouge) et qui a pu être étendue au-delà de 1100 nm dans le cas des dérivés portant un ligand terpyridine. L’analyse des propriétés optoélectroniques de façon empirique et théorique a montré un impact significatif de la cyclométalation et ouvert la voie pour leur étude en tant que photosensibilisateurs en OPV et en DSSC. La capacité d’un des complexes à photo-injecter un électron dans la bande de conduction du semi-conducteur TiO2 a été démontré en collaboration avec le groupe du Pr Gerald J. Meyer à University of North Carolina at Chapel Hill, premier pas vers une utilisation dans les cellules solaires à pigments photosensibles. La stabilité des complexes en solution s’est toutefois avérée problématique et des pistes de solutions sont suggérées basées sur les connaissances acquises dans le cadre de cette thèse.

Is phraseology the third articulation of language? Fresh insights into a theoretical conundrum

Is phraseology the third articulation of language? Fresh insights into a theoretical conundrum Jean-Pierre Colson University of Louvain (Louvain-la-Neuve, Belgium) Although the notion of phraseology is now used across a wide range of linguistic disciplines, its definition and the classification of phraseological units remain a subject of intense debate. It is generally agreed that phraseology implies polylexicality, but this term is problematic as well, because it brings us back to one of the most controversial topics in modern linguistics: the definition of a word. On the other hand, another widely accepted principle of language is the double articulation or duality of patterning (Martinet 1960): the first articulation consists of morphemes and the second of phonemes. The very definition of morphemes, however, also poses several problems, and the situation becomes even more confused if we wish to take phraseology into account. In this contribution, I will take the view that a corpus-based and computational approach to phraseology may shed some new light on this theoretical conundrum. A better understanding of the basic units of meaning is necessary for more efficient language learning and translation, especially in the case of machine translation. Previous research (Colson 2011, 2012, 2013, 2014), Corpas Pastor (2000, 2007, 2008, 2013, 2015), Corpas Pastor & Leiva Rojo (2011), Leiva Rojo (2013), has shown the paramount importance of phraseology for translation. A tentative step towards a coherent explanation of the role of phraseology in language has been proposed by Mejri (2006): it is postulated that a third articulation of language intervenes at the level of words, including simple morphemes, sequences of free and bound morphemes, but also phraseological units. I will present results from experiments with statistical associations of morphemes across several languages, and point out that (mainly) isolating languages such as Chinese are interesting for a better understanding of the interplay between morphemes and phraseological units. Named entities, in particular, are an extreme example of intertwining cultural, statistical and linguistic elements. Other examples show that the many borrowings and influences that characterize European languages tend to give a somewhat blurred vision of the interplay between morphology and phraseology. From a statistical point of view, the cpr-score (Colson 2016) provides a methodology for adapting the automatic extraction of phraseological units to the morphological structure of each language. The results obtained can therefore be used for testing hypotheses about the interaction between morphology, phraseology and culture. Experiments with the cpr-score on the extraction of Chinese phraseological units show that results depend on how the basic units of meaning are defined: a morpheme-based approach yields good results, which corroborates the claim by Beck and Mel'čuk (2011) that the association of morphemes into words may be similar to the association of words into phraseological units. A cross-linguistic experiment carried out for English, French, Spanish and Chinese also reveals that the results are quite compatible with Mejri’s hypothesis (2006) of a third articulation of language. Such findings, if confirmed, also corroborate the notion of statistical semantics in language. To illustrate this point, I will present the PhraseoRobot (Colson 2016), a computational tool for extracting phraseological associations around key words from the media, such as Brexit. The results confirm a previous study on the term globalization (Colson 2016): a significant part of sociolinguistic associations prevailing in the media is related to phraseology in the broad sense, and can therefore be partly extracted by means of statistical scores. References Beck, D. & I. Mel'čuk (2011). Morphological phrasemes and Totonacan verbal morphology. Linguistics 49/1: 175-228. Colson, J.-P. (2011). La traduction spécialisée basée sur les corpus : une expérience dans le domaine informatique. In : Sfar, I. & S. Mejri, La traduction de textes spécialisés : retour sur des lieux communs. Synergies Tunisie n° 2. Gerflint, Agence universitaire de la Francophonie, p. 115-123. Colson, J.-P. (2012). Traduire le figement en langue de spécialité : une expérience de phraséologie informatique. In : Mogorrón Huerta, P. & S. Mejri (dirs.), Lenguas de especialidad, traducción, fijación / Langues spécialisées, figement et traduction. Encuentros Mediterráneos / Rencontres Méditerranéennes, N°4. Universidad de Alicante, p. 159-171. Colson, J.-P. (2013). Pratique traduisante et idiomaticité : l’importance des structures semi-figées. In : Mogorrón Huerta, P., Gallego Hernández, D., Masseau, P. & Tolosa Igualada, M. (eds.), Fraseología, Opacidad y Traduccíon. Studien zur romanischen Sprachwissenschaft und interkulturellen Kommunikation (Herausgegeben von Gerd Wotjak). Frankfurt am Main, Peter Lang, p. 207-218. Colson, J.-P. (2014). La phraséologie et les corpus dans les recherches traductologiques. Communication lors du colloque international Europhras 2014, Association Européenne de Phraséologie. Université de Paris Sorbonne, 10-12 septembre 2014. Colson, J-P. (2016). Set phrases around globalization : an experiment in corpus-based computational phraseology. In: F. Alonso Almeida, I. Ortega Barrera, E. Quintana Toledo and M. Sánchez Cuervo (eds.), Input a Word, Analyse the World: Selected Approaches to Corpus Linguistics. Newcastle upon Tyne: Cambridge Scholars Publishing, p. 141-152. Corpas Pastor, G. (2000). Acerca de la (in)traducibilidad de la fraseología. In: G. Corpas Pastor (ed.), Las lenguas de Europa: Estudios de fraseología, fraseografía y traducción. Granada: Comares, p. 483-522. Corpas Pastor, G. (2007). Europäismen - von Natur aus phraseologische Äquivalente? Von blauem Blut und sangre azul. In: M. Emsel y J. Cuartero Otal (eds.), Brücken: Übersetzen und interkulturelle Kommunikationen. Festschrift für Gerd Wotjak zum 65. Geburtstag, Fráncfort: Peter Lang, p. 65-77. Corpas Pastor, G. (2008). Investigar con corpus en traducción: los retos de un nuevo paradigma [Studien zur romanische Sprachwissenschaft und interkulturellen Kommunikation, 49], Fráncfort: Peter Lang. Corpas Pastor, G. (2013). Detección, descripción y contraste de las unidades fraseológicas mediante tecnologías lingüísticas. In Olza, I. & R. Elvira Manero (eds.) Fraseopragmática. Berlin: Frank & Timme, p. 335-373. Leiva Rojo, J. (2013). La traducción de unidades fraseológicas (alemán-español/español-alemán) como parámetro para la evaluación y revisión de traducciones. In: Mellado Blanco, C., Buján, P, Iglesias N.M., Losada M.C. & A. Mansilla (eds), La fraseología del alemán y el español: lexicografía y traducción. ELS, Etudes Linguistiques / Linguistische Studien, Band 11. München: Peniope, p. 31-42. Leiva Rojo, J. & G. Corpas Pastor (2011). Placing Italian idioms in a foreign milieu: a case study. In: Pamies Bertrán, A., Luque Nadal, L., Bretana, J. &; M. Pazos (eds), (2011). Multilingual phraseography. Second Language Learning and Translation Applications. Baltmannsweiler: Schneider Verlag (Colección: Phraseologie und Parömiologie, 28), p. 289-298. Martinet, A. (1966). Eléments de linguistique générale. Paris: Colin. Mejri, S. (2006). Polylexicalité, monolexicalité et double articulation. Cahiers de Lexicologie 2: 209-221.

MULTI-BAND BOSE HUBBARD MODELS AND EFFECTIVE THREE-BODY INTERACTIONS

Experiments with ultracold atoms in optical lattice have become a versatile testing ground to study diverse quantum many-body Hamiltonians. A single-band Bose-Hubbard (BH) Hamiltonian was first proposed to describe these systems in 1998 and its associated quantum phase-transition was subsequently observed in 2002. Over the years, there has been a rapid progress in experimental realizations of more complex lattice geometries, leading to more exotic BH Hamiltonians with contributions from excited bands, and modified tunneling and interaction energies. There has also been interesting theoretical insights and experimental studies on “un- conventional” Bose-Einstein condensates in optical lattices and predictions of rich orbital physics in higher bands. In this thesis, I present our results on several multi- band BH models and emergent quantum phenomena. In particular, I study optical lattices with two local minima per unit cell and show that the low energy states of a multi-band BH Hamiltonian with only pairwise interactions is equivalent to an effec- tive single-band Hamiltonian with strong three-body interactions. I also propose a second method to create three-body interactions in ultracold gases of bosonic atoms in a optical lattice. In this case, this is achieved by a careful cancellation of two contributions in the pair-wise interaction between the atoms, one proportional to the zero-energy scattering length and a second proportional to the effective range. I subsequently study the physics of Bose-Einstein condensation in the second band of a double-well 2D lattice and show that the collision aided decay rate of the con- densate to the ground band is smaller than the tunneling rate between neighboring unit cells. Finally, I propose a numerical method using the discrete variable repre- sentation for constructing real-valued Wannier functions localized in a unit cell for optical lattices. The developed numerical method is general and can be applied to a wide array of optical lattice geometries in one, two or three dimensions.

Wide Field of View Spectroscopy Using Fabry-Perot Interferometers

We present a high resolution spectrometer consisting of dual solid Fabry-Perot Interferometers (FPIs). This work is intended to be an all inclusive documentation of the instrument including discussion of the design of this instrument, the methods used in data reduction, and the analysis of these data. Each FPI is made of a single piece of L-BBH2 glass which has a high index of refraction n~2.07 with a thickness on the order of 100 μm. Each is then coated with partially reflective mirrors to create a resonant cavity and thus achieve a spectral resolution of R~30,000. Running the FPIs in tandem reduces the overlapping orders and allows for a much wider free spectral range and higher contrast. We will also discuss the properties of the FPIs which we have measured. This includes the tuning of the FPIs which is achieved by adjusting the temperature and thus changing the FPI gap and the refractive index of the material. The spectrometer then moves spatially in order to get spectral information at every point in the field of view. We select spectral lines for further analysis and create maps of the line depths across the field. Using this technique we are able to measure the fluorescence of chlorophyll in plants and attempt to observe zodiacal light. In the chlorophyll analysis we are able to detect chlorophyll fluorescence using the line depth in a plant using the sky as a reference solar spectrum. This instrument has possible applications in either a cubesat or aerial observations to measure bulk plant activity over large areas.

Evaluation of the conductor-like screening model for real solvents for the prediction of the water activity coefficient at infinite dilution in ionic liquids

Ionic liquids (ILs) have attracted great attention, from both industry and academia, as alternative fluids for very different types of applications. The large number of cations and anions allow a wide range of physical and chemical characteristics to be designed. However, the exhaustive measurement of all these systems is impractical, thus requiring the use of a predictive model for their study. In this work, the predictive capability of the conductor-like screening model for real solvents (COSMO-RS), a model based on unimolecular quantum chemistry calculations, was evaluated for the prediction water activity coefficient at infinite dilution, gamma(infinity)(w), in several classes of ILs. A critical evaluation of the experimental and predicted data using COSMO-RS was carried out. The global average relative deviation was found to be 27.2%, indicating that the model presents a satisfactory prediction ability to estimate gamma(infinity)(w) in a broad range of ILs. The results also showed that the basicity of the ILs anions plays an important role in their interaction with water, and it considerably determines the enthalpic behavior of the binary mixtures composed by Its and water. Concerning the cation effect, it is possible to state that generally gamma(infinity)(w) increases with the cation size, but it is shown that the cation-anion interaction strength is also important and is strongly correlated to the anion ability to interact with water. The results here reported are relevant in the understanding of ILs-water interactions and the impact of the various structural features of its on the gamma(infinity)(w) as these allow the development of guidelines for the choice of the most suitable lLs with enhanced interaction with water.

Spatial and temporal country-wide survey of temephos resistance in Brazilian populations of Aedes aegypti

The organophosphate temephos has been the main insecticide used against larvae of the dengue and yellow fever mosquito ( Aedes aegypti ) in Brazil since the mid-1980s. Reports of resistance date back to 1995; however, no systematic reports of widespread temephos resistance have occurred to date. As resistance investigation is paramount for strategic decision-making by health officials, our objective here was to investigate the spatial and temporal spread of temephos resistance in Ae. aegypti in Brazil for the last 12 years using discriminating temephos concentrations and the bioassay protocols of the World Health Organization. The mortality results obtained were subjected to spatial analysis for distance interpolation using semi-variance models to generate maps that depict the spread of temephos resistance in Brazil since 1999. The problem has been expanding. Since 2002-2003, approximately half the country has exhibited mosquito populations resistant to temephos. The frequency of temephos resistance and, likely, control failures, which start when the insecticide mortality level drops below 80%, has increased even further since 2004. Few parts of Brazil are able to achieve the target 80% efficacy threshold by 2010/2011, resulting in a significant risk of control failure by temephos in most of the country. The widespread resistance to temephos in Brazilian Ae. aegypti populations greatly compromise effective mosquito control efforts using this insecticide and indicates the urgent need to identify alternative insecticides aided by the preventive elimination of potential mosquito breeding sites.