Measuring cluster masses with CMB lensing: a statistical approach

We present a method for measuring the masses of galaxy clusters using the imprint of their gravitational lensing signal on the cosmic microwave background (CMB) temperature anisotropies. The method first reconstructs the projected gravitational potential with a quadratic estimator and then applies a matched filter to extract cluster mass. The approach is well-suited for statistical analyses that bin clusters according to other mass proxies. We find that current experiments, such as Planck, the South Pole Telescope and the Atacama Cosmology Telescope, can practically implement such a statistical methodology, and that future experiments will reach sensitivities sufficient for individual measurements of massive systems. As illustration, we use simulations of Planck observations to demonstrate that it is possible to constrain the mass scale of a set of 62 massive clusters with prior information from X-ray observations, similar to the published Planck ESZ-XMM sample. We examine the effect of the thermal (tSZ) and kinetic (kSZ) Sunyaev-Zeldovich (SZ) signals, finding that the impact of the kSZ remains small in this context. The stronger tSZ signal, however, must be actively removed from the CMB maps by component separation techniques prior to reconstruction of the gravitational potential. Our study of two such methods highlights the importance of broad frequency coverage for this purpose. A companion paper presents application to the Planck data on the ESZ-XMM sample.Comment: 9 pages, 5 figures, version accepted for publication in A&

Point Source Confusion in SZ Cluster Surveys

We examine the effect of point source confusion on cluster detection in Sunyaev-Zel'dovich (SZ) surveys. A filter matched to the spatial and spectral characteristics of the SZ signal optimally extracts clusters from the astrophysical backgrounds. We calculate the expected confusion (point source and primary cosmic microwave background [CMB]) noise through this filter and quantify its effect on the detection threshold for both single and multiple frequency surveys. Extrapolating current radio counts, we estimate that confusion from sources below 100 microJy limits single-frequency surveys to 1-sigma detection thresholds of Y 3.10^{-6} arcmin^2 at 30 GHz and Y 10^{-5} arcmin^2 at 15 GHz (for unresolved clusters in a 2 arcmin beam); these numbers are highly uncertain, and an extrapolation with flatter counts leads to much lower confusion limits. Bolometer surveys must contend with an important population of infrared point sources. We find that a three-band matched filter with 1 arcminute resolution (in each band) efficiently reduces confusion, but does not eliminate it: residual point source and CMB fluctuations contribute significantly the total filter noise. In this light, we find that a 3-band filter with a low-frequency channel (e.g, 90+150+220 GHz) extracts clusters more effectively than one with a high frequency channel (e.g, 150+220+300 GHz).Comment: Accepted for publication in Astronomy & Astrophysics; Updated grant information in acknowledgement

Self-gravity, resonances and orbital diffusion in stellar discs

Fluctuations in a stellar system's gravitational field cause the orbits of stars to evolve. The resulting evolution of the system can be computed with the orbit-averaged Fokker-Planck equation once the diffusion tensor is known. We present the formalism that enables one to compute the diffusion tensor from a given source of noise in the gravitational field when the system's dynamical response to that noise is included. In the case of a cool stellar disc we are able to reduce the computation of the diffusion tensor to a one-dimensional integral. We implement this formula for a tapered Mestel disc that is exposed to shot noise and find that we are able to explain analytically the principal features of a numerical simulation of such a disc. In particular the formation of narrow ridges of enhanced density in action space is recovered. As the disc's value of Toomre's $Q$ is reduced and the disc becomes more responsive, there is a transition from a regime of heating in the inner regions of the disc through the inner Lindblad resonance to one of radial migration of near-circular orbits via the corotation resonance in the intermediate regions of the disc. The formalism developed here provides the ideal framework in which to study the long-term evolution of all kinds of stellar discs.Comment: 11 pages, 7 figure

Distribution functions for resonantly trapped orbits in the Galactic disc

The present-day response of a Galactic disc stellar population to a non-axisymmetric perturbation of the potential has previously been computed through perturbation theory within the phase-space coordinates of the unperturbed axisymmetric system. Such an Eulerian linearized treatment however leads to singularities at resonances, which prevent quantitative comparisons with data. Here, we manage to capture the behaviour of the distribution function (DF) at a resonance in a Lagrangian approach, by averaging the Hamiltonian over fast angle variables and re-expressing the DF in terms of a new set of canonical actions and angles variables valid in the resonant region. We then follow the prescription of Binney (2016), assigning to the resonant DF the time average along the orbits of the axisymmetric DF expressed in the new set of actions and angles. This boils down to phase-mixing the DF in terms of the new angles, such that the DF for trapped orbits only depends on the new set of actions. This opens the way to quantitatively fitting the effects of the bar and spirals to Gaia data in terms of distribution functions in action space.Comment: 8 pages, 7 figures, accepted for publication in MNRA

Finite type invariants and fatgraphs

We define an invariant $\nabla_G(M)$ of pairs M,G, where M is a 3-manifold obtained by surgery on some framed link in the cylinder $S\times I$, S is a connected surface with at least one boundary component, and G is a fatgraph spine of S. In effect, $\nabla_G$ is the composition with the $\iota_n$ maps of Le-Murakami-Ohtsuki of the link invariant of Andersen-Mattes-Reshetikhin computed relative to choices determined by the fatgraph G; this provides a basic connection between 2d geometry and 3d quantum topology. For each fixed G, this invariant is shown to be universal for homology cylinders, i.e., $\nabla_G$ establishes an isomorphism from an appropriate vector space $\bar{H}$ of homology cylinders to a certain algebra of Jacobi diagrams. Via composition $\nabla_{G'}\circ\nabla_G^{-1}$ for any pair of fatgraph spines G,G' of S, we derive a representation of the Ptolemy groupoid, i.e., the combinatorial model for the fundamental path groupoid of Teichmuller space, as a group of automorphisms of this algebra. The space $\bar{H}$ comes equipped with a geometrically natural product induced by stacking cylinders on top of one another and furthermore supports related operations which arise by gluing a homology handlebody to one end of a cylinder or to another homology handlebody. We compute how $\nabla_G$ interacts with all three operations explicitly in terms of natural products on Jacobi diagrams and certain diagrammatic constants. Our main result gives an explicit extension of the LMO invariant of 3-manifolds to the Ptolemy groupoid in terms of these operations, and this groupoid extension nearly fits the paradigm of a TQFT. We finally re-derive the Morita-Penner cocycle representing the first Johnson homomorphism using a variant/generalization of $\nabla_G$.Comment: 39 page

Learning to Localize and Align Fine-Grained Actions to Sparse Instructions

Automatic generation of textual video descriptions that are time-aligned with video content is a long-standing goal in computer vision. The task is challenging due to the difficulty of bridging the semantic gap between the visual and natural language domains. This paper addresses the task of automatically generating an alignment between a set of instructions and a first person video demonstrating an activity. The sparse descriptions and ambiguity of written instructions create significant alignment challenges. The key to our approach is the use of egocentric cues to generate a concise set of action proposals, which are then matched to recipe steps using object recognition and computational linguistic techniques. We obtain promising results on both the Extended GTEA Gaze+ dataset and the Bristol Egocentric Object Interactions Dataset

Triagem enzimática e caracterização morfológica de fungos filamentosos isolados de amostras de indústria têxtil

Anais do VI Encontro de Iniciação Científica e II Encontro Anual de Iniciação ao Desenvolvimento Tecnológico e Inovação – EICTI 2017 - 04 a 06 de outubro de 2017 - temática Ciências BiológicasA atividade industrial para a produção têxtil utiliza-se de etapas de operações unitárias geradoras de grandes cargas de efluentes com alto potencial poluidor. Apesar de tais efluentes receberem um tratamento que precede o lançamento em um corpo hídrico, muitas vezes o mesmo apresenta resultados insatisfatórios na remoção de determinados agentes poluentes, devido ao desconhecimento por parte dos operadores da natureza química dos produtos utilizados, bem como a infinidade de produtos utilizados durante cada etapa industrial. Desta forma, efluentes originários da produção de tecidos têm se apresentado como um causador de impactos ambientais diversos em corpos d’agua e em suas áreas de entornoUniversidade Federal da Integração Latino-Americana (Unila); Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Fundação Araucária; Parque Tecnológico Itaipu (PTI) e Companhia de Saneamento do Paraná (SANEPAR

AMILASE E LIPASE PRODUZIDAS POR FUNGOS DE EFLUENTE TÊXTIL: LEVANTAMENTO CIENTÍFICO E TECNOLÓGICO

Trabalho de Conclusão de Curso apresentado ao Instituto Latino-Americano de Ciências da Vida e da Natureza da Universidade Federal da Integração Latino-Americana, como requisito parcial à obtenção do título de Bacharel em Biotecnologia.A utilização de enzimas microbianas na indústria biotecnológica é uma ferramenta muito vantajosa em diversos setores industriais uma vez que, as enzimas podem ser obtidas por métodos mais simples, podem ser sintetizadas em grandes quantidades e em uma produção relativamente menos dispendiosa, podendo apresentar estabilidade em várias condições fermentativas. As enzimas de origem fúngica, podem ser consideradas predominantes em relação as enzimas bacterianas, característica que pode favorecer sua utilização em processos fermentativos em batelada bem como métodos extrativos operados em baixo custo. Este trabalho objetivou avaliar quantitativamente as publicações e patentes levantadas envolvendo amilases e lipases produzidas por fungos recuperados da indústria têxtil nos últimos 10 anos. Para isso, foi realizado um levantamento de publicações a partir das plataformas acadêmicas NCBI-Pubmed, Web of Science e Scopus, e de patentes, através dos escritórios de patentes do INPI, UPSTO e EPO, por meio do repositório Spacenet. Foram encontradas 238.382 patentes. Desse total, 142 foram originadas no INPI (0,06%), 43.801 (18,37%) no EPO e 194.439 (81,57%) emitidas no USPTO. Entretanto, nenhuma patente foi encontrada utilizando amilase e lipases produzidas por fungos de amostras têxteis. Para os últimos 10 anos, foram encontrados 136 artigos nas bases de dados, sendo que alguns dos artigos estão em mais de uma plataforma. Somente 30 desses artigos apresentam índice de impacto entre 1.0 e 2.5. Nenhum desses artigos mencionaram o uso de efluentes da indústria têxtil como fontes para bioprospecção de fungos produtores de amilases ou lipases. O presente estudo enfatiza a necessidade da busca das enzimas amilase e lipase oriundas de fungos recuperados de efluentes industriais têxteis para futuros estudos biotecnológicos

Quasar Host Environments: The view from Planck

We measure the far-infrared emission of the general quasar (QSO) population using Planck observations of the Baryon Oscillation Spectroscopic Survey QSO sample. By applying multi-component matched multi-filters to the seven highest Planck frequencies, we extract the amplitudes of dust, synchrotron and thermal Sunyaev-Zeldovich (SZ) signals for nearly 300,000 QSOs over the redshift range $0.1<z<5$. We bin these individually low signal-to-noise measurements to obtain the mean emission properties of the QSO population as a function of redshift. The emission is dominated by dust at all redshifts, with a peak at $z \sim 2$, the same location as the peak in the general cosmic star formation rate. Restricting analysis to radio-loud QSOs, we find synchrotron emission with a monochromatic luminosity at $100\,\rm{GHz}$ (rest-frame) rising from $\overline{L_{\rm synch}}=0$ to $0.2 \, {\rm L_\odot} {\rm Hz}^{-1}$ between $z=0$ and 3. The radio-quiet subsample does not show any synchrotron emission, but we detect thermal SZ between $z=2.5$ and 4; no significant SZ emission is seen at lower redshifts. Depending on the supposed mass for the halos hosting the QSOs, this may or may not leave room for heating of the halo gas by feedback from the QSO.Comment: 14 pages, 11 figures, accepted by A&