The Art of Creating Photographic Portrait Sketches

The art of creating a professional quality photographic por­trait is a skill that an undergraduate student may take their entire educational career to master. On a separate path, an undergraduate may also take their career to master freehand drawing and sketching. When these two creative paths align, the results can be extraordinary. This poster will showcase the journey of one undergraduate student to combine their photographic and artistic portrait skills along with software techniques to create one of a kind photographic portrait sketches. The poster will serve as a best practices guide to the creation of each image

A Markov chain model for the decoding probability of sparse network coding

Random linear network coding has been shown to offer an efficient communication scheme, leveraging a remarkable robustness against packet losses. However, it suffers from a high-computational complexity, and some novel approaches, which follow the same idea, have been recently proposed. One of such solutions is sparse network coding (SNC), where only few packets are combined with each transmission. The amount of data packets to be combined can be set from a density parameter/distribution, which could be eventually adapted. In this paper, we present a semi-analytical model that captures the performance of SNC on an accurate way. We exploit an absorbing Markov process, where the states are defined by the number of useful packets received by the decoder, i.e., the decoding matrix rank, and the number of non-zero columns at such matrix. The model is validated by the means of a thorough simulation campaign, and the difference between model and simulation is negligible. We also include in the comparison of some more general bounds that have been recently used, showing that their accuracy is rather poor. The proposed model would enable a more precise assessment of the behavior of SNC techniques.This work has been supported by the Spanish Government (Ministerio de Economía y Competitividad, Fondo Europeo de Desarrollo Regional, FEDER) by means of the projects COSAIF, “Connectivity as a Service: Access for the Internet of the Future” (TEC2012-38754-C02-01), and ADVICE (TEC2015-71329-C2-1-R). This work was also financed in part by the TuneSCode project (No. DFF 1335-00125) granted by the Danish Council for Independent Research

Sigmodontinos fósiles (rodentia, muroidea, sigmodontinae) de América del Sur : estado actual de su conocimiento y prospectiva

Fil: Pardiñas, Ulyses Francisco José. Departamento Científico Paleontología Vertebrados; Museo de La PlataFil: D`Elía, Guillermo. University of Michigan Museum of Zoology; Ann Arbor; USAFil: Ortiz, Pablo E.. Cátedra de Paleozoología II; Facultad de Ciencias Naturales e Instituto Miguel Lillo; Miguel Lillo 205; 4000 San Miguel de Tucumán; Argentin

Micromamíferos del Holoceno tardío del sitio arqueológico ?El Shincal de Quimivil?, provincia de Catamarca, Argentina

En el presente trabajo se analizan las asociaciones de micromamíferos registradas en el sitio arqueológico El Shincal de Quimivil, provincia de Catamarca, Argentina. El yacimiento Representa tres períodos de ocupación humana, abarcando un intervalo entre los siglos XIV y XVII. La alta frecuencia de elementos vertebrales e incisivos aislados junto con la ausencia de claras marcas de disolución sugiere que el conjunto no sería producto de la actividad de depredadores, sino que estaría relacionada con causas eto-ecológicas de las especies registradas. La muestra, dominada por Calomys cf. C. musculinus, está integrada además por un didelfimorfio (Thylamys cf. T. pallidior), tres especies de roedores Sigmodontinos (Akodon cf. A. dolores, Graomys griseoflavus y Phyllotis xanthopygus) y dos de roedores caviomorfos (Ctenomys sp., y Microcavia australis). La composición taxonómica cuantitativa y cualitativa de la muestra de tiempos históricos, con la dominancia de Calomys cf., C. musculinus sobre otros pequeños mamíferos, sugiere modificaciones respecto al ambiente original, probablemente relacionada al establecimiento de agroecosistemas incipientes. La ausencia de Eligmodontia , un género cuyas especies habitan ambientes áridos con escasa vegetación y suelos desnudos arenosos o pedregosos, puede vincularse a condiciones locales de mayor humedad que en el presente y/o al aprovechamiento de este sector a través de prácticas de riego por parte de los pobladores. El escaso conocimiento de las asociaciones de pequeños mamíferos para tiempos pre-hispánicos, históricos y modernos en este sector del Monte impide una comparación adecuada de la muestra estudiada y la reconstrucción de un esquema ambiental a partir del registro arqueofaunístico. El Microambiente particularmente húmedo por el establecimiento de áreas agrícolas constituye un factor adicional que dificulta su comparación con muestras adicionales provenientes de áreas circundantes. Fil: Agnolin, Federico L.. Universidad Maimónides. Area de Investigaciones Biomédicas y Biotecnológicas. Centro de Estudios Biomédicos, Biotecnológicos, Ambientales y Diagnósticos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales; ArgentinaFil: Ortiz, Pablo E.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - CONICET- Tucumán. Instituto Superior de Correlación Geológica; Argentina. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo; ArgentinaFil: Bogan, Sergio. Universidad Maimónides. Area de Investigaciones Biomédicas y Biotecnológicas. Centro de Estudios Biomédicos, Biotecnológicos, Ambientales y Diagnósticos; ArgentinaFil: Lucero, Sergio. Universidad Nacional de La Plata. Facultad de Ciencias Agrarias y Forestales. Instituto Fitotécnico de "Santa Catalina"; Argentina. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. División Zoología de Vertebrados. Seccion de Mastozoologia; Argentin

Improvement in PWV estimation from GPS due to the absolute calibration of antenna phase center variations

Climatology of column-integrated atmospheric water vapor over Spain has been carried out by means of three techniques: soundings, sun photometers and GPS receivers. Comparing data from stations equipped with more than one of these instruments, we found that a large discontinuity occurred on November 6, 2006, in the differences between the data series from GPS receivers and those from the other two techniques. Prior to that date, the GPS data indicate a wet bias of 2–3 mm for all stations when compared with sounding or photometer data, whereas after that date this bias practically reduces to zero. The root mean square error also decreases about half of its value. On November 6, 2006, the International GNSS Service adopted an absolute calibration model for the antennas of the GPS satellites and receivers instead of the relative one. This change is expected to be an improvement, increasing the accuracy of station position determination and consequently benefiting post-processing products such as zenith total delay from which the atmospheric water vapor content is calculated

Columnar aerosol characterization over Scandinavia and Svalbard

An overview of sun photometer measurements of aerosol properties in Scandinavia and Svalbard was provided by Toledano et al. (2012) thanks to the collaborative effort of various research groups from different countries that maintain a number of observation sites in the European Arctic and sub-Arctic regions. The spatial coverage of this kind of data has remarkably improved in the last years, thanks, among other things, to projects carried out within the framework of the International Polar Year 2007-08. The data from a set of operational sun photometer sites belonging either to national or international measurement networks (AERONET, GAW-PFR) were evaluated. The direct sun observations provided spectral aerosol optical depth (AOD) and Ångström exponent (AE), that are parameters with sufficient long-term records for a first characterization at all sites. At the AERONET sites, microphysical properties derived from inversion of sun-sky radiance data were also examined. AOD (500nm) ranged from 0.08 to 0.10 in Arctic and sub-Arctic sites whereas the aerosol load was higher in more populated areas in Southern Scandinavia (average AOD about 0.10–0.12 at 500 nm).Financial support was provided by: the Spanish CICYT (CGL2008-05939-CO3-01/CLI, CGL2009-09740 and CGL2011-13085-E); the Norwegian Research Council for POLARCAT-Norway; and the Swedish National Space Board and ESA for Norrköping and Palgrunden sites. The research leading to these results has received funding from the European Union Seventh Framework Programme (FP7/2007-2013) under grant agreement Nr. 262254 [ACTRIS]

Primer registro de Microcavia jayat (Rodentia, Caviidae) para la provincia de La Rioja

El género Microcavia Gervais y Ameghino, 1880 incluye cinco especies vivientes de roedores caviomorfos de tamaño pequeño, endémicas del sur de América del Sur. En Argentina se han registrado cuatro de ellas; M. shiptoni (Thomas, 1925), M. maenas Thomas, 1898, M. australis (Geoffroy St.-Hilaire y d'Orbigny, 1833) y M. jayat Teta, Ojeda, Lucero y D? Elía, 2018. Esta última especie sólo se conoce en siete localidades del Chaco Seco (semiárido) de Santiago del Estero. Sobre la base de restos cráneo-mandibulares recuperados de egagrópilas de lechuzas, informamos el primer registro de M. jayat para La Rioja. Las muestras fueron colectadas en áreas de Chaco Seco del extremo sur de la provincia, en edificaciones del Dique Azulón (Departamento General Ocampo). Los elementos recuperados (MNI= 22), consistentes en 41 fragmentos de cráneos y 42 hemimandíbulas, presentan los caracteres diagnósticos de la especie, incluyendo arcos cigomáticos expandidos y con procesos paraorbitales conspicuos, huesos yugales posteriormente extendidos por detrás del borde posterior de la fosa glenoidea, cresta palatal en forma de corazón y borde posterior del paladar de contorno trapezoidal. El nuevo registro implica una extensión en la distribución conocida de la especie de aproximadamente 390 km hacia el sudoeste, respecto de la localidad más cercana, y constituye el primer registro de la misma en el Chaco Serrano. Este caviomorfo coexiste en la localidad de colecta con al menos otras siete especies de pequeños mamíferos (registradas en el mismo conjunto de egagrópilas), incluyendo el marsupial Thylamys sp. (MNI= 3), los caviomorfos Ctenomys sp. (MNI= 7) y Galea leucoblephara (MNI= 1) y los sigmodontinos Akodon dolores (MNI= 2), Calomys cf. C. laucha/ musculinus (MNI= 8), C. venustus (MNI= 7) y Graomys chacoensis (MNI= 10).Fil: Jayat, Jorge Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - Tucumán. Unidad Ejecutora Lillo; Argentina. Universidad Nacional de Chilecito; ArgentinaFil: Ortiz, Pablo Edmundo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto Superior de Correlación Geológica. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Departamento de Geología. Cátedra Geología Estructural. Instituto Superior de Correlación Geológica; ArgentinaFil: Bustamante, E.. Universidad Nacional de Chilecito; ArgentinaFil: Teta, Pablo Vicente. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaXXXI Jornadas Argentinas de MastozoologíaLa RiojaArgentinaSociedad Argentina para el estudio de los MamíferosCentro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioj

Insulin and GLP-1 infusions demonstrate the onset of adipose-specific insulin resistance in a large fasting mammal: potential glucogenic role for GLP-1.

Prolonged food deprivation increases lipid oxidation and utilization, which may contribute to the onset of the insulin resistance associated with fasting. Because insulin resistance promotes the preservation of glucose and oxidation of fat, it has been suggested to be an adaptive response to food deprivation. However, fasting mammals exhibit hypoinsulinemia, suggesting that the insulin resistance-like conditions they experience may actually result from reduced pancreatic sensitivity to glucose/capacity to secrete insulin. To determine whether fasting results in insulin resistance or in pancreatic dysfunction, we infused early- and late-fasted seals (naturally adapted to prolonged fasting) with insulin (0.065 U/kg), and a separate group of late-fasted seals with low (10 pM/kg) or high (100 pM/kg) dosages of glucagon-like peptide-1 (GLP-1) immediately following a glucose bolus (0.5g/kg), and measured the systemic and cellular responses. Because GLP-1 facilitates glucose-stimulated insulin secretion, these infusions provide a method to assess pancreatic insulin-secreting capacity. Insulin infusions increased the phosphorylation of insulin receptor and Akt in adipose and muscle of early and late fasted seals; however the timing of the signaling response was blunted in adipose of late fasted seals. Despite the dose-dependent increases in insulin and increased glucose clearance (high dose), both GLP-1 dosages produced increases in plasma cortisol and glucagon, which may have contributed to the glucogenic role of GLP-1. Results suggest that fasting induces adipose-specific insulin resistance in elephant seal pups, while maintaining skeletal muscle insulin sensitivity, and therefore suggests that the onset of insulin resistance in fasting mammals is an evolved response to cope with prolonged food deprivation

LPS-Induced Genes in Intestinal Tissue of the Sea Cucumber Holothuria glaberrima

Metazoan immunity is mainly associated with specialized cells that are directly involved with the immune response. Nevertheless, both in vertebrates and invertebrates other organs might respond to immune activation and participate either directly or indirectly in the ongoing immune process. However, most of what is known about invertebrate immunity has been restricted to immune effector cells and little information is available on the immune responses of other tissues or organs. We now focus on the immune reactions of the intestinal tissue of an echinoderm. Our study employs a non-conventional model, the echinoderm Holothuria glaberrima, to identify intestinal molecules expressed after an immune challenge presented by an intra-coelomic injection of lipopolysaccharides (LPS). The expression profiles of intestinal genes expressed differentially between LPS-injected animals and control sea water-injected animals were determined using a custom-made Agilent microarray with 7209 sea cucumber intestinal ESTs. Fifty (50) unique sequences were found to be differentially expressed in the intestine of LPS-treated sea cucumbers. Seven (7) of these sequences represented homologues of known proteins, while the remaining (43) had no significant similarity with any protein, EST or RNA database. The known sequences corresponded to cytoskeletal proteins (Actin and alpha-actinin), metabolic enzymes (GAPDH, Ahcy and Gnmt), metal ion transport/metabolism (major yolk protein) and defense/recognition (fibrinogen-like protein). The expression pattern of 11 genes was validated using semi-quantitative RT-PCR. Nine of these corroborated the microarray results and the remaining two showed a similar trend but without statistical significance. Our results show some of the molecular events by which the holothurian intestine responds to an immune challenge and provide important information to the study of the evolution of the immune response

Seasonal variation in the diet of the Common Barn-Owl (Tyto alba) in a disturbed environment of the Argentinean Dry Chaco

Se estudió la dieta de la Lechuza de Campanario (Tyto alba) en un sector del Chaco Seco en Santiago del Estero, Argentina. A partir de 332 egagrópilas colectadas entre 2007 y 2009 se analizó la variación estacional en el número y la biomasa de los ítems presa, la diversidad y la amplitud de nicho trófico. Entre los 1170 individuos predados se registraron 14 ítems presa, correspondientes a mamíferos (87%), aves (7%) e insectos (6%). Los roedores cricétidos constituyeron el grupo más frecuente (85%) y con el mayor aporte de biomasa (>75%), con una amplia dominancia de Calomys spp. Durante el primer año la abundancia de micromamíferos en la estación seca alcanzó valores máximos, en tanto que aves e insectos mostraron el patrón opuesto. La diversidad y la amplitud de nicho trófico presentaron valores máximos durante la estación húmeda y la superposición trófica fue más baja entre muestras de estaciones diferentes. La variación estacional de la biomasa en la dieta se debió principalmente al mayor consumo de aves durante la estación húmeda de 2008. En la estación húmeda del segundo año de muestreo la dieta presentó un comportamiento anómalo, en algunos casos completamente opuesto a lo esperado, probablemente relacionado a una marcada disminución en las precipitaciones. Los resultados confirman una dieta generalista–oportunista, con un alto consumo de micromamíferos durante la estación seca explicado por sus tamaños poblaciones elevados. La modificación del ambiente explicaría la extrema dominancia de Calomys spp., como ya fuera documentado en otras áreas de Argentina.We studied the diet of the Common Barn-Owl (Tyto alba) in the Dry Chaco of Santiago del Estero, Argentina. From 332 pellets collected between 2007 and 2009 we analyzed the seasonal variation in number and biomass of prey-items, diversity, and trophic niche width. We identified 1170 individuals belonging to 14 prey-items, corresponding to mammals (87%), birds (7%) and insects (6%). Cricetid rodents were the most frequent group (85%) with the highest biomass contribution (>75%), being Calomys spp. the most abundant item. During the dry season of the first year, the abundance of micromammals reached the highest values while birds and insects showed the opposite pattern. Diversity and trophic niche width showed their highest values during the wet season and niche overlap was lower between samples of different seasons. Seasonal variation in biomass was mostly due to a higher consumption of birds during the wet season of 2008. In the wet season of the second year the diet showed an anomalous behaviour, in some cases showing the opposite of the expected patterns, probably related to a pronounced decrease in rainfall. The results of this study allow us to confirm a generalist-opportunistic diet, with high consumption of micromammals during the dry season probably explained by their high population sizes. Environmental modifications could be explaining the extreme dominance of Calomys spp., as it has been documented in other regions of Argentina