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In this talk, I will provide an introduction to abelian functor calculus, a version of functor calculus inspired by classical constructions of Dold and Puppe, and of Eilenberg and Mac Lane. I will then explain how the analog of a directional derivative in abelian functor calculus gives rise to the structure of a cartesian differential category for a particular category of functors of abelian categories. Author affiliation: Union College Unreviewed Faculty Non UBC

One of the main objectives of statistical climatology is to extract relevant information hidden in complex spatial-temporal climatological datasets. In impact studies, heavy rainfall are of primary importance for risk assessment linked to floods and other hydro- logical events. At an hourly time scale, precipitation distributions often strongly differ from Gaussianity. To identify spatial patterns, most well-known statistical techniques are based on the concept of intra and inter clusters variances (like the k-means algorithm or PCA Author affiliation: CNRS Unreviewed Non UBC Other

The hypoelliptic Laplacian gives a natural interpolation between the Laplacian and the geodesic flow. This interpolation preserves important spectral quantities. I will explain its construction in the context of compact Lie groups: in this case, the hypoelliptic Laplacian is the analytic counterpart to localization in equivariant cohomology on the coadjoint orbits of loop groups. The construction for noncompact reductive groups ultimately produces a geometric formula for the semisimple orbital integrals, which are the key ingredient in Selberg trace formula. In both cases, the construction of the hypoelliptic Laplacian involves the Dirac operator of Kostant. Author affiliation: Université Paris-Sud Unreviewed Faculty Non UBC

We present some results concerning the mass aspect and positivity of mass for asymptotically locally hyperbolic (ALH) manifolds. This is based on joint work Piotr Chrusciel, Luke Nguyen and Tim Paetz. Author affiliation: University of Miami Unreviewed Faculty Non UBC

In the sixth episode of our Below the Radar Conversations Series, we talk with Angela Marie MacDougall, Executive Director of Battered Women's Support Services here in Vancouver, Canada. With our host Am Johal, she discusses how COVID-19 is affecting gender inequality and violence within intimate relationships. Angela Marie MacDougall is the Executive Director of Battered Women's Support Services Society. You can learn more here:https://www.bwss.org/

Elucidating how ecological and evolutionary mechanisms interact to produce and maintain biodiversity is a fundamental problem in evolutionary ecology. We investigate this issue by focusing on how physiological evolution affects performance and species coexistence along the thermal niche axis in replicated radiations of Anolis lizards, groups best known for resource partitioning based on morphological divergence. We find repeated divergence in thermal physiology within these radiations, and that this divergence significantly affects performance within natural thermal environments. Morphologically similar species that co-occur invariably differ in their thermal physiology, providing evidence that physiological divergence facilitates species co-existence within anole communities. Despite repeated divergence in traits of demonstrable ecological importance, phylogenetic comparative analyses indicate that physiological traits have evolved more slowly than key morphological traits related to the structural niche. Phylogenetic analyses also reveal that physiological divergence is correlated with divergence in broad-scale habitat climatic features commonly used to estimate thermal niche evolution, but that the latter incompletely predicts variation in the former. We provide comprehensive evidence for repeated adaptive evolution of physiological divergence within Anolis adaptive radiations, including the complementary roles of physiological and morphological divergence in promoting community-level diversity. We recommend greater integration of performance-based traits into analyses of climatic niche evolution, as they facilitate a more complete understanding of the phenotypic and ecological consequences of climatic divergence. Topt data PRSLBOptimal temperature datapr jamaica ctmax PRSLBCTmax (heat tolerance) data

This dataset contains methane and nitrous oxide dissolved gas concentration, dissolved methane carbon isotope, and ancillary hydrographic data from research cruises in the North American Arctic Ocean between 2015-2018. Ocean samples for methane and nitrous oxide analysis were collected from Niskin bottles mounted on a CTD rosette. Water was collected into glass serum bottles and allowed to overflow three times before preserving with mercuric chloride and sealing with with butyl rubber stoppers and aluminum crimp seals. Gas concentrations were determined using a purge and trap system coupled to a gas chromatograph/mass spectrometer, following the method of Capelle et al. (2015). Equilibrium dry atmospheric concentrations were 328.25, 329.14, 330.11, and 330.96 ppb for N2O and 1919.64, 1933.67, 1934.92, and 1933.50 ppb for CH4 in 2015, 2016, 2017, and 2018, respectively. Equilibrium dissolved concentrations were calculated from the measured temperature and salinity following Wiesenburg and Guinasso (1979) for CH4 and Weiss and Price (1980) for N2O. Equilibrium concentrations were calculated based on sample temperature and salinity and the atmospheric N2O or CH4 concentrations measured at Barrow, Alaska by the NOAA Earth System Research Laboratory Global Monitoring Division (Dlugokencky et al., 2020a,b), with corrections to local sea level pressure and 100% humidity. Oxygen concentration was determined using an oxygen sensor mounted on the Niskin rosette, calibrated with discrete samples analyzed by Winkler titration. The mixed layer depth was defined based on a potential density difference criterion of 0.125 kg/m³ relative to the density at 5 m depth, using CTD profiles binned to 1 m. The mixed layer depth was set to 5 m as a minimum. The instantaneous gas transfer velocities and fluxes are based on the instantaneous wind speed at the time of sampling. The 30-day weighted gas transfer velocities and fluxes are integrated over the residence time of the gas in the mixed layer, using up to the prior 30 days of observations, following the method of Teeter et al. (2018) as described in the main manuscript of Manning et al. (2022). The 60-day weighted gas transfer velocities and fluxes are integrated over the residence time of the gas in the mixed layer, using the prior 60 days of observations, following the method of Teeter et al. (2018) as described in the main manuscript of Manning et al. (2022). Atmospheric sea level pressure was obtained from the NCEP/NCAR reanalysis product, which is provided by the NOAA-ESRL Physical Sciences Laboratory (https://psl.noaa.gov/data/gridded). Fractional ice cover was obtained from the EUMETSAT Ocean and Sea Ice Satellite Application Facility (https://osi-saf.eumetsat.int). Sea ice concentration product AMSR-2 (identifier OSI-408) was used in 2017–2018 and SSMIS (identifier OSI-401-b) was used in 2015–2016.

Ce Sea-Bird SeaCAT SBE19plus V2 7036 a été déployé le 2019-07-31 au Cambridge Bay. Cambridge Bay est située sur Victoria Island, dans la région de Kitikmeot, au Nunavut, au Canada. Cet instrument est un Conductivité/Température/Profondeur. Conductivité Température Profondeur (CTD) est un nom abrégé pour un ensemble d'instruments qui contient des capteurs permettant de mesurer la conductivité, la température et la pression de l'eau de mer. La salinité, la vitesse du son, la profondeur et la densité sont des variables qui peuvent être dérivées des mesures par capteurs. Les CTD peuvent transporter d'autres instruments et capteurs, comme des capteurs d'oxygène, des capteurs de turbidité et des fluoromètres. Il a été deployé sur une plateforme fixe. Les données de ce déploiement sont archivées et accessibles sur l'infrastructure numérique Oceans 3.0 du Réseau Canadien des Océans (ONC), avec assurance de la qualité et produits dérivés selon les conventions établies. The Sea-Bird SeaCAT SBE19plus V2 7036 was deployed on 2019-07-31 at Cambridge Bay. Cambridge Bay is located on Victoria Island in the Kitikmeot Region of Nunavut, Canada. This device is a Conductivity Temperature Depth. Conductivity Temperature Depth (CTD) is an instrument package that contains sensors for measuring the conductivity, temperature, and pressure of seawater. Salinity, sound velocity, depth and density are variables that can be derived from sensor measurements. CTDs can carry additional instruments and sensors such as oxygen sensors, turbidity sensors and fluorometers. It was deployed on a fixed platform. Data from this deployment were archived and made available through Ocean Networks Canada's Oceans 3.0 digital infrastructure, with quality assurance and derived data products following established practices.

Quadrature-based moment methods (QBMM) are employed to solve generalized population balance equations (GPBE) and are especially useful for poly-disperse multiphase flows. Starting from a closed GPBE, the unclosed moment equations are formulated and closed using QBMM. The accuracy of the closure is controlled by the order of the moments used in QBMM. For example, poly-disperse gasâ particle flows can be described by a GPBE for the particle-phase mass-velocity number distribution function (NDF). In practice, the choice of the moments used in the closure is crucial. For particles with a continuous distribution of masses (e.g., same material with different diameters), the mean velocity and granular temperature of each size can be different. Thus, in addition to size moments, the velocity moments conditioned on size are needed to approximate the NDF. Here, the particle-phase model found from the GPBE with the Boltzmannâ Enskog collision operator will be used to explain the methodology. Once the moment equations have been formulated, the numerical algorithms used to solve them must be consistent with the underlying GBPE. For example, the numerical methods employed to solve the spatial advection terms and the source terms must guarantee that the transported moments remain realizable (i.e., they must correspond to a NDF). This can be accomplished with kinetic-based, finite-volume methods. With QBMM, the NDF is represented by a finite set of weighted delta functions, corresponding to discrete velocities and sizes, that agree with the transported moments. Thus, it is often convenient to develop algorithms in terms of the quadrature variables in place of the moments. Employing applications from poly-disperse gasâ particle flows, several examples of the numerical issues arising with QBMM will be discussed, along with some open issues related to the numerical algorithms. Author affiliation: Iowa State University Unreviewed Faculty Non UBC