A Bijection for Unicellular Partitioned Bicolored Maps

In the present paper we construct a bijection that relates a set of unicellular bicolored maps to a set of couples of ordered bicolored trees and partial permutations. This bijection allows us to derive an elegant formula for the enumeration of unicellular bicolored maps , an analogue of the well-known Harer-Zagier result for unicolored one-face maps

Taxonomic review of the Neotropical Tetragonoderus quadriguttatus assemblage (Coleoptera: Carabidae: Cyclosomini) with description of T. deuvei, new species, and new West Indian and Nearctic locality records

The Tetragonoderus (Peronoscelis) quadriguttatus assemblage is a postulated monophyletic part of the intersectus complex. This assemblage is characterized against a background that includes review of a classification of the genus and comparison, in the form of a key, to other unrelated Western Hemisphere genera that share elongate tibial spurs with Tetragonoderus Dejean. The principal, easily observed feature that unites the three members (T. laevigatus Chaudoir, 1876; T. deuvei, new species (type locality: Cuijaba, Mato Grosso, Brazil), and T. quadriguttatus Dejean) of the quadriguttatus assemblage is the four-spotted elytra (two spots per elytron). These species are treated in detail, including key, synonymy (as required), comparisons, description (external and male genitalic features), habitat (if known), locality data, and geographical range map. Also, T. subfasciatus Putzeys, 1846, the elytral color pattern of whose members may be confused with the spotted pattern of the quadriguttatus assemblage, is treated similarly. The following new synonymies were established: T. quadriguttatus Dejean 1829 = T. columbicus Steinheil 1875 = T. lacordairei Chaudoir 1876 = T. tetragrammus Chaudoir 1876; and T. laevigatus Chaudoir 1876 = T. chaudoiri Liebke 1928 (replacement name for the junior homonym, T. unicolor Chaudoir, 1876). Lectotypes are designated for T. unicolor Chaudoir, T. lacordairei Chaudoir, and T. subfasciatus Putzeys. A neotype is designated for T. quadriguttatus Dejean. New distribution records in the West Indies for T. quadriguttatus are recorded for the islands of Grand Cayman, Jamaica and Hispaniola. These records may be the result of recent natural overseas dispersal from northern South America, or they may be the result of human-mediated accidental introduction, or a combination of both. The southern Floridian (Nearctic) records for T. laevigatus probably represent a recent accidental introduction through commerce, followed by dispersal through flights of adults

Patterning and microstructure of penguin plumage

textPenguins (Sphenisciformes) exhibit an array of derived feather features. The characters describing penguin integument that are used in the phylogenetic reconstruction have not been reassessed since they were written in 2005. I reassessed all integument characters for extant penguins and outgroup taxa. The phylogenetic tree constructed using the reassessed integument characters does not differ in topology from the original phylogenetic tree except that several outgroup relationships become less resolved. This indicates that conclusions drawn by previous authors about the relationships among extant penguins using the original tree are still valid. However, the reconstruction of the integument of the common ancestor of Spheniscidae no longer remains the same. Caution should be exercised when using museum bird skins to score integument characters because these colors can change over time, especially in the bill and legs. In addition to examining macro characteristics of penguin feathers, I also examined the microstructure of Gentoo Penguin (Pygoscelis papua) feathers in order to assess the presence of nanofibers, which had thus far only been found in the Little Penguin (Eudyptula minor). Nanofibers create the structural blue color in the dorsal feathers in the Little Penguin. I discovered nanofibers in all pigmented feathers in the Gentoo Penguin. The nanofibers in black parts of the feathers are overprinted by melanosomes. An amorphous keratin matrix exists in the white breast feathers, creating white structural color, but nanofibers are absent. My data suggest that penguin integument is even more modified relative to other birds than previously thought. Implications for penguin color patterning are presented concerning countershading and intraspecific signaling. The data presented in my study raise new questions about the origin and potential functions of penguin plumage structure and coloration.Geological Science

Topological dualities in the Ising model

We relate two classical dualities in low-dimensional quantum field theory: Kramers-Wannier duality of the Ising and related lattice models in $2$ dimensions, with electromagnetic duality for finite gauge theories in $3$ dimensions. The relation is mediated by the notion of boundary field theory: Ising models are boundary theories for pure gauge theory in one dimension higher. Thus the Ising order/disorder operators are endpoints of Wilson/'t Hooft defects of gauge theory. Symmetry breaking on low-energy states reflects the multiplicity of topological boundary states. In the process we describe lattice theories as (extended) topological field theories with boundaries and domain walls. This allows us to generalize the duality to non-abelian groups; finite, semi-simple Hopf algebras; and, in a different direction, to finite homotopy theories in arbitrary dimension.Comment: 62 pages, 22 figures; v2 adds important reference [S]; v2 has reworked introduction, additional reference [KS], and minor changes; v4 for publication in Geometry and Topology has all new figures and a few minor changes and additional reference

Topological dualities in the Ising model

We relate two classical dualities in low-dimensional quantum field theory: Kramers-Wannier duality of the Ising and related lattice models in $2$ dimensions, with electromagnetic duality for finite gauge theories in $3$ dimensions. The relation is mediated by the notion of boundary field theory: Ising models are boundary theories for pure gauge theory in one dimension higher. Thus the Ising order/disorder operators are endpoints of Wilson/'t Hooft defects of gauge theory. Symmetry breaking on low-energy states reflects the multiplicity of topological boundary states. In the process we describe lattice theories as (extended) topological field theories with boundaries and domain walls. This allows us to generalize the duality to non-abelian groups; finite, semi-simple Hopf algebras; and, in a different direction, to finite homotopy theories in arbitrary dimension

Morphological and genetic evidence supports the separation of two tapinoma ants (Formicidae, dolichoderinae) from the atlantic forest biome

The taxonomic boundaries of many Neotropical ant species of the genus Tapinoma are still unclear. Tapinoma atriceps and T. atriceps breviscapum are two morphologically similar taxa which occur sympatrically in the southern Atlantic Forest of Brazil. Some characters such as the scape length and head shape suggest that these taxa may be different species. We used DNA analysis and morphological evidence, including scanning electron microscopy, to evaluate the taxonomic validity of these taxa. We found distinct morphological characteristics that allow separating them as two different species, Tapinoma atriceps and Tapinoma breviscapum status novo, and this decision is supported by the DNA results, where Tapinoma atriceps was recovered as a lineage independent of T. breviscapum

ECOLOGICAL, MOLECULAR, AND MORPHOLOGICAL DATA: A SYNERGISTIC APPROACH TO RESOLVE SPECIES LIMITS OF \u3cem\u3eLYTOPYLUS\u3c/em\u3e FROM THE AREA DE CONSERVACIÓN GUANACASTE, COSTA RICA (HYMENOPTERA: BRACONIDAE: AGATHIDINAE)

Lytopylus is species-rich genus of Agathidinae (Hymenoptera: Braconidae: Agathidinae), but limited information of the genus has been published. Morphological, molecular, and ecological data were compared to resolve the species limits of Lytopylus reared from caterpillars collected the Area de Conservación Guanacaste (ACG) in Costa Rica. Molecular data were initially used to hypothesize species limits, and morphological and host use data were employed to make a final decision when molecular data was indecisive, e.g., when the genetic difference between species was slight. Thirty-two new species are described with image plates of each species. Phylogenetic analyses of the barcode region of the cytochrome c oxidase subunit I (COI) mitochondrial gene was conducted using Neighbor-Joining (NJ) and the Maximum likelihood (ML) analysis. A concatenated COI+28S dataset was analyzed by ML analysis to elucidate evolutionary patterns in ecological characters

Micro‐computed tomography for the 3D time‐resolved investigation of monodisperse droplet generation in a co‐flow setup

Droplet generation in microfluidic devices has emerged as a promising approach for the design of highly controllable processes in the chemical and pharmaceutical industry. However, droplet generation is still not fully understood due to the complexity of the underlying physics. In this work, micro‐computed tomography is applied to investigate droplet formation in a circular channel in a co‐flow configuration at different flow conditions (Ca < 0.001). The application of an in‐house developed scanning protocol assisted by comprehensive image processing allows for the time‐resolved investigation of droplet formation. By tracking different droplet parameters (length, radii, volume, surface, Laplace pressure) the effect of flow conditions on droplet progression is determined. As characteristic for the squeezing regime, final droplet size was nearly independent of Ca for higher Ca tested. For lower Ca, the final droplet size increased with decreasing Ca, which points to the leaking regime that was recently introduced in the literature

A multidisciplinary approach to investigate plant-pathogen interactions

Pseudomonas syringae es una bacteria fitopatógena de gran interés tanto académico como económico, ya que afecta a gran variedad de cultivos hortícolas y ornamentales. Durante la interacción entre P. syringae y la planta se producen fenómenos de evasión de defensa cuyo estudio es el objetivo principal de esta tesis. Las poblaciones bacterianas han sido consideradas durante mucho tiempo clonales, y como tales, genética y fenotípicamente idénticas. Sin embargo, trabajos realizados durante las últimas décadas han demostrado que en condiciones de estrés, como las que se encuentra una bacteria fitopatógena en su hospedador, se pueden formar distintas subpoblaciones bacterianas (biestabilidad). Estos cambios se han asociado en bacterias patógenas de animales a modificaciones epigenéticas que causan heterogeneidad fenotípica reversible sin alterar el genotipo (Casadesús y Low, 2013). Pseudomonas syringae es una bacteria fitopatógena, cuya virulencia es dependiente del Sistema de Secreción Tipo III (T3SS). Durante la tesis, se ha analizado la expresión de tres genes del T3SS: un gen que codifica para una proteína estructural (hrcU), un regulador general del sistema (hrpL) y un efector (hopAB1). Hemos demostrado que la expresión de los tres genes es heterogénea cuando la bacteria crece en medio mínimo (HIM), y esta heterogeneidad se convierte en bistabilidad para el caso del efector hopAB1 durante la fase de crecimiento exponencial. En el interior de la planta, la bistabilidad de hopAB1 se intensifica, y la expresión del regulador hrpL se vuelve bistable. Además, la bistabilidad se revierte en pocas horas, indicando un origen no genético del proceso. La separación de poblaciones bacterianas basada en la expresión de hopAB1 y la posterior inoculación en planta demuestra que dichas diferencias en expresión tienen un efecto en la virulencia de la bacteria. Durante la interacción planta-patógeno, las plantas detectan a los microorganismos mediante receptores de membrana que reconocen patrones moleculares asociados a patógenos (PAMPs). Este reconocimiento lleva a la planta a activar una respuesta de defensa generalista llamada PTI (PAMP-Triggered Immunity). Pseudomonas syringae, mediante su T3SS, puede translocar proteínas llamadas efectores al interior de la célula vegetal. Algunos de estos efectores suprimen la respuesta PTI, permitiendo a la bacteria crecer y colonizar. Sin embargo, la planta ha desarrollado receptores intracelulares capaces de reconocer algunos de estos efectores, desencadenando respuestas fuertes y específicas (ETI, Effector-Triggered Immunity), que dispara la muerte celular local (HR, Hypersensitive Response) y la activación de una respuesta sistémica en la planta (SAR, Systemic Acquired Resistance). El efector HopZ1a suprime PTI, ETI y SAR (Macho et al., 2010; Lewis et al., 2014). HopZ1a se autoacetila en la lisina 289 (Lee et al., 2012), aunque este residuo no es esencial para la actividad del efector (Rufian et al., 2015; Ma et al., 2015). Aunque se han propuesto varias dianas moleculares de HopZ1a dentro de la planta, ninguna guarda una relación directa con la supresión de defensa descrita previamente. Una de estas dianas, ZED1, es una pseudoquinasa cuya única función es la detección de la actividad de HopZ1a para activar una respuesta de defensa (Lewis et al., 2013). Además, otros efectores de la familia YopJ/HopZ acetilan MAPK quinasas en sus hospedadores. En Arabidopsis existen 10 MAPK quinasas, una de las cuales, ZIP1, está implicada en la activación de defensas basales. Este fenotipo nos llevó a proponer a ZIP1 como la diana mediante la cual HopZ1a suprime defensas. Hemos demostrado que la supresión de defensas de HopZ1a es dependiente de ZIP1, y que ambas proteínas interaccionan tanto in vitro como in planta. Además, HopZ1a acetila a ZIP1 en una lisina esencial para su función, y no descrita previamente