172 research outputs found

    Boustrophedonic Frames: Quasi-Optimal L2 Caching for Textures in GPUs

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    © 2023 Copyright held by the owner/author(s). This document is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/ This document is the Accepted version of a Published Work that appeared in final form in 32nd International Conference on Parallel Architectures and Compilation Techniques (PACT), Viena, Austria, October 2023. To access the final edited and published work see https://doi.org/10.1109/PACT58117.2023.00019Literature is plentiful in works exploiting cache locality for GPUs. A majority of them explore replacement or bypassing policies. In this paper, however, we surpass this exploration by fabricating a formal proof for a no-overhead quasi-optimal caching technique for caching textures in graphics workloads. Textures make up a significant part of main memory traffic in mobile GPUs, which contributes to the total GPU energy consumption. Since texture accesses use a shared L2 cache, improving the L2 texture caching efficiency would decrease main memory traffic, thus improving energy efficiency, which is crucial for mobile GPUs. Our proposal reaches quasi-optimality by exploiting the frame-to-frame reuse of textures in graphics. We do this by traversing frames in a boustrophedonic1 manner w.r.t. the frame-to-frame tile order. We first approximate the texture access trace to a circular trace and then forge a formal proof for our proposal being optimal for such traces. We also complement the proof with empirical data that demonstrates the quasi-optimality of our no-cost proposal

    Constraints on the origin and evolution of magmas in the Payún Matrú Volcanic Field, Quaternary Andean Back-arc of Western Argentina

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    The Payún Matrú Volcanic Field (Pleistocene-Holocene) is located in the Andean back-arc of the Southern Volcanic Zone, western Argentina, and is contemporaneous with the Andean volcanic arc at the same latitude. It includes two polygenetic, mostly trachytic volcanoes: Payún Matrú (with a summit caldera 8 km wide) and Payún Liso (a smaller stratovolcano). The volcanic field includes about 200 scoria cones and alkali basaltic and trachybasaltic lava flows, forming two basaltic fields around Payún Matrú. New 40Ar¯39Ar ages extend the activity of Payún Matrú up to 700 ka. The major and trace element and Sr-Nd isotopic compositions of the basaltic lavas and Payún Matrú rocks indicate that the trachytes of Payún Matrú are the result of fractional crystallization of basaltic parent magmas without significant upper crustal contamination, and that the basalts have a geochemical similarity to ocean island basalt (La/Nb=0·8-1·5, La/Ba =0·05-0·08). The Sr-Nd isotopic compositions of the basaltic to trachytic rocks range between 0·703813 and 0·703841 (87Sr/86Sr) and 0·512743 and 0·512834 (143Nd/144Nd). Mass-balance and Rayleigh fractionation models support the proposed origin of the trachytes, and an assimilation-fractional crystallization model indicates a low degree of upper crustal contamination in the youngest trachytes. Magnesium numbers (45-55) and contents of Ni(<20-90 ppm) and Cr (30-180 ppm) in the lavas in the basaltic fields indicate that these are not primary magmas. The data also suggest that the basaltic lavas originated in the asthenospheric mantle, probably within the spinel stability field and beneath an attenuated continental lithosphere in the back-arc area. The lack of a slab-fluid signature in the Payún Matrú Volcanic Field rocks, along with unpublished and published geophysical results (mantle tomography and electrical conductivity anomalies) suggest that magmas were generated by decompression-induced melting of upwelling mantle.Facultad de Ciencias Naturales y MuseoCentro de Investigaciones Geológica

    Automated detection of filaments in the large scale structure of the universe

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    We present a new method to identify large scale filaments and apply it to a cosmological simulation. Using positions of haloes above a given mass as node tracers, we look for filaments between them using the positions and masses of all the remaining dark-matter haloes. In order to detect a filament, the first step consists in the construction of a backbone linking two nodes, which is given by a skeleton-like path connecting the highest local dark matter (DM) density traced by non-node haloes. The filament quality is defined by a density and gap parameters characterising its skeleton, and filament members are selected by their binding energy in the plane perpendicular to the filament. This membership condition is associated to characteristic orbital times; however if one assumes a fixed orbital timescale for all the filaments, the resulting filament properties show only marginal changes, indicating that the use of dynamical information is not critical for the method. We test the method in the simulation using massive haloes(M>1014M>10^{14}h1M^{-1}M_{\odot}) as filament nodes. The main properties of the resulting high-quality filaments (which corresponds to 33\simeq33% of the detected filaments) are, i) their lengths cover a wide range of values of up to 150150 h1^{-1}Mpc, but are mostly concentrated below 50h1^{-1}Mpc; ii) their distribution of thickness peaks at d=3.0d=3.0h1^{-1}Mpc and increases slightly with the filament length; iii) their nodes are connected on average to 1.87±0.181.87\pm0.18 filaments for 1014.1M\simeq 10^{14.1}M_{\odot} nodes; this number increases with the node mass to 2.49±0.28\simeq 2.49\pm0.28 filaments for 1014.9M\simeq 10^{14.9}M_{\odot} nodes.Comment: 17 pages, 13 figures, MNRAS Accepte

    Constraints on the origin and evolution of magmas in the Payún Matrú Volcanic Field, Quaternary Andean Back-arc of Western Argentina

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    The Payún Matrú Volcanic Field (Pleistocene-Holocene) is located in the Andean back-arc of the Southern Volcanic Zone, western Argentina, and is contemporaneous with the Andean volcanic arc at the same latitude. It includes two polygenetic, mostly trachytic volcanoes: Payún Matrú (with a summit caldera 8 km wide) and Payún Liso (a smaller stratovolcano). The volcanic field includes about 200 scoria cones and alkali basaltic and trachybasaltic lava flows, forming two basaltic fields around Payún Matrú. New 40Ar¯39Ar ages extend the activity of Payún Matrú up to 700 ka. The major and trace element and Sr-Nd isotopic compositions of the basaltic lavas and Payún Matrú rocks indicate that the trachytes of Payún Matrú are the result of fractional crystallization of basaltic parent magmas without significant upper crustal contamination, and that the basalts have a geochemical similarity to ocean island basalt (La/Nb=0·8-1·5, La/Ba =0·05-0·08). The Sr-Nd isotopic compositions of the basaltic to trachytic rocks range between 0·703813 and 0·703841 (87Sr/86Sr) and 0·512743 and 0·512834 (143Nd/144Nd). Mass-balance and Rayleigh fractionation models support the proposed origin of the trachytes, and an assimilation-fractional crystallization model indicates a low degree of upper crustal contamination in the youngest trachytes. Magnesium numbers (45-55) and contents of Ni(<20-90 ppm) and Cr (30-180 ppm) in the lavas in the basaltic fields indicate that these are not primary magmas. The data also suggest that the basaltic lavas originated in the asthenospheric mantle, probably within the spinel stability field and beneath an attenuated continental lithosphere in the back-arc area. The lack of a slab-fluid signature in the Payún Matrú Volcanic Field rocks, along with unpublished and published geophysical results (mantle tomography and electrical conductivity anomalies) suggest that magmas were generated by decompression-induced melting of upwelling mantle.Facultad de Ciencias Naturales y MuseoCentro de Investigaciones Geológica

    Evaluación del efecto de tres condiciones de cultivo in vitro en la calidad de plántulas de caña de azúcar propagadas en Biorreactores de Inmersión Temporal

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    Structural and functional deficiencies that affect survival during acclimatization are present in micropropagated plants. The current study was carried out to determine the effect of three in vitro culture conditions (autotrophic, mixotrophic and moderate mixotrophic) on the morph-physiological and biochemical behavior of plantlets of sugar cane propagated in Temporary Immersion Bioreactors (BIT). Morphological and physiological indicators and key enzymes of carbon metabolism were evaluated. Plantlets that were subjected to autotrophic conditions did not survive due to the stress caused by the absence of sucrose in the culture medium. For this reason it could not be evaluated. The best results were obtained for the condition of moderate mixotrofical. In this case, the morphological variables, height of the plants, fresh weight and dry weight, responded positively. It was minimum the answer of the net photosynthesis in vitro and increased it notably from the second week of acclimatization. Plants with a mixotrophic growth showed very high values of transpiration and estomatic conductance at the beginning of the elongation and during the first week of acclimatization. This group of plants took a longer time than the rest in achieving the control of the loss of water and in reaching a functional stability. Plants that showed a bigger activity of pyruvate kinase were those coming from mixotrophic conditions. An inverse behavior was observed in the phosphoenolpyruvate carboxylase. The activities of syntase sucruse and the neutral invertase were superior for the mixotrofic conditions.Key words: autotrofic, enzymes, mixotrofic, photosynthesisLas plantas micropropagadas poseen deficiencias estructurales y funcionales que comprometen su supervivencia durante la aclimatización. El objetivo de este trabajo fue determinar el efecto de tres condiciones de cultivo in vitro (autotrófica, mixotrófica y de mixotrofismo moderado) en el comportamiento morfo-fisiológico y bioquímico de plántulas de caña de azúcar propagadas en Biorreactores de Inmersión Temporal (BIT). Se evaluaron indicadores morfológicos, fisiológicos y enzimas clave del metabolismo del carbono. Las plántulas que se sometieron a condiciones autotróficas no lograron sobrevivir debido al estrés propiciado por la ausencia de sacarosa en el medio de cultivo. Por esta razón no pudieron ser evaluadas. Los mejores resultados se obtuvieron para la condición de mixotrofismo moderado. En este caso, las variables morfológicas altura de las plantas, masas fresca y seca respondieron positivamente. La respuesta de la fotosíntesis neta fue muy baja in vitro y aumentó notablemente a partir de la segunda semana de aclimatización. Para las plántulas con un desarrollo mixotrófico se observaron valores de transpiración y conductancia estomática muy elevados al inicio de la elongación y durante la primera semana de aclimatización. Este grupo de plántulas se tardó más que el resto en lograr el control de la pérdida de agua y en alcanzar una estabilidad funcional. Las plantas que mostraron una mayor actividad de la Piruvato Quinasa fueron provenientes de condiciones mixotróficas. La Fosfoenol Piruvato Carboxilasa tuvo un comportamiento totalmente inverso. Las actividades de la Sacarosa Sintasa y la Invertasa Neutra, al igual que la Piruvato Quinasa, fueron superiores para las condiciones mixotróficas.Palabras clave: autotrofismo, enzimas, fotosíntesis, mixotrofism

    Revealing full chemical forms of lead in wine with combined XRF-NMR technologies

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    Since 1953, The World Organization of Vine and Wine (OIV) Member States have reduced the lead maximum limits (ML) in wines, down to 0.05 mg/L (2018). Evidently, this ML value is too restrictive for wine industry as it excludes from international market a significant portion of wine production. Currently, the Codex Committee on Contaminants in Foods and OIV had recognized the value of gathering robust and novel data to better assess the best lowest ML for wine industry. Currently, there is not a direct statement within international reference documents, of which chemical form of lead must be controlled and/ or reduced. This work presents for the first time a method combining Energy Dispersive X-Ray analysis (EDAX) and Nuclear Magnetic Resonance (NMR) spectroscopies in order to determine presence and concentrations of major and trace elements of lead and other element moieties in wine that can allow to better redefine lead's ML. By identification of K, L, M, radiation shells with additional αβi labelling of lead's major and minor components with semi-quantitative XRF, combined with chemical-shift analysis of inorganic Pb4+, Pb2+ and/or organo-lead within wine samples, we propose a full discrimination framework to disentangle and quantify different chemical forms of lead

    Incorporación del estudio de ADN fetal en sangre materna al cribado de cromosomopatías

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    Objetivo: Evaluar la efectividad del cribado combinado de primer trimestre para la detección prenatal de aneuploidías tras 6 años de implantación en nuestro servicio y su repercusión en la disminución de pruebas diagnósticas invasivas. Se propone establecer un protocolo para incorporar el estudio de ADN fetal en sangre materna a partir de las revisiones bibliográficas publicadas. Método: Se evaluó el riesgo de anomalía cromosómica fetal en 3177 gestaciones mediante cribado combinado de primer trimestre entre enero de 2011 y diciembre de 2014. Se revisaron las amniocentesis realizadas desde que se instauró el cribado combinado en 2008 comparándolas con las de los 5 años anteriores. Resultados: La tasa de detección del cribado para trisomía 21 fue del 94,4% y la tasa de falsos positivos de 6,4%. En el año 2005 estábamos realizando 194 amniocentesis, tras 6 años de implantación del cribado, en el año 2013 se realizaron 35 amniocentesis lo que implica una disminución del 70%. Conclusiones: El cribado combinado de primer trimestre ha demostrado una mayor tasa de detección para trisomía 21 que el cribado de segundo trimestre y/o la edad materna, además de que ha llevado a una importante reducción en el número de pruebas invasivas. En los próximos años la incorporación del estudio de ADN fetal mejorará la detección de aneuploidías, con una drástica disminución de las pruebas invasivas por lo que se hace necesario la implantación de nuevos protocolos. Aims: To evaluate the effectiveness of first trimester combined screening in the prenatal detection of aneuploidy after 6 years of implantation in our service and its impact in reducing invasive diagnostic tests. It is proposed to establish a protocol to incorporate the study of fetal DNA in maternal blood from published literature reviews. Methods: The risk of fetal chromosomal anomalies was assessed in 3177 pregnancies with first trimester combined screening between January 2009 and December 2014. The amniocenteses performed were checked against those of the previous 5 years. Results: The detection rate of screening for trisomy 21 was 94.4% and the false-positive rate was 6.4%. In 2005 there were 194 amniocenteses. In 2013, 5 years after the introduction of screening, 68 amniocenteses were performed, representing a 70% reduction in invasive procedures. Conclusions: First trimester combined screening has shown a higher detection rate for trisomy 21 that the second trimester screening and/or maternal age, and has substantially reduced the use of invasive prenatal diagnostics procedures. In the coming years, the incorporation of the study of fetal DNA improve the detection of aneuploidys with a drastic reduction of invasive tests so that, the implementation of new protocols is necessary

    Application of multi-sensor advanced DInSAR analysis to severe land subsidence recognition: Alto Guadalentín Basin (Spain)

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    Multi-sensor advanced DInSAR analyses have been performed and compared with two GPS station measurements, in order to evaluate the land subsidence evolution in a 20-year period, in the Alto Guadalentín Basin where the highest rate of man-induced subsidence (> 10 cm yr&minus;1) of Europe had been detected. The control mechanisms have been examined comparing the advanced DInSAR data with conditioning and triggering factors (i.e. isobaths of Plio-Quaternary deposits, soft soil thickness and piezometric level)

    Optimization of Pathogenicity Tests for Selection of Native Isolates of Entomopathogenic Fungi Isolated from Citrusgrowing Areas of México on Adults ofDiaphorina citriKuwayama (Hemiptera: Liviidae)

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    Huanglonbing (HLB), es considerado una de las más letales enfermedades de los cítricos alrededor del mundo, y ha alcanzado las principales áreas de producción de limón Mexicano (Citrus latifolia Tanaka) en la costa del pacifico de México. Los productores han iniciado el uso de insecticidas para controlar las poblaciones del psílido asiático de los cítricos, Diaphorina citri Kuwayama (Hemiptera: Liviidae), el vector del patógeno ‘Candidatus Liberibacter asiaticus’ asociado con el HLB. Actualmente los costos de los insecticidas y los efectos secundarios de su uso son las principales preocupaciones, ya que podrían perjudicar la estrategia de manejo contra el vector; y por lo tanto, alternativas ecológicas y económicamente viables a los insecticidas convencionales serian necesarias a corto plazo. Por tanto, el objetivo de este estudio fue evaluar la patogenicidad de 27 aislados nativos y 3 cepas de hongos entomopatógenos para determinar su potencial como agentes de control biológico sobre Diaphorina citri usando 2 diferentes métodos de bioensayo. Los bioensayos fueron realizados bajo condiciones de laboratorio (26 ± 2 °C, 60 ± 5% H.R y 16:8 h L:O) mediante la exposición de insectos adultos a una concentración de 1 × 108 conidios por mililitro utilizando 2 diferentes métodos de aplicación, es decir, por asperjado de esporas en las plántulas de cítricos y por asperjado directo a los psílidos adultos. Los resultados mostraron que para el asperjado directo a los adultos los aislados HIB-24 (B. bassiana) y HIB-32 (I. fumosorosea) mostraron el mayor porcentaje de mortalidad (60.66%). Respecto al asperjado de plántulas el aislado HIB-19 (I. fumosorosea) mostró el mayor porcentaje de mortalidad (62.02%). Los resultados de este estudio demuestran el potencial para el uso de hongos entomopatógenos en el manejo de D. citri en México. ABSTRACT Huanglongbing (HLB), considered one of the most lethal diseases of citrus worldwide, has reached the main areas of Mexican lime (Citrus latifolia Tanaka) fruit production on the Pacific coast of México. Growers have initiated intensive use of insecticides in order to control populations of the Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Liviidae), the vector of the pathogen, ‘Candidatus Liberibacter asiaticus’ associated with huanglongbing. Presently, costs of insecticides and the side effects of their use are major concerns, because they could impair the management strategy against the vector; and thus, ecologically and economically viable alternatives to conventional insecticides are required in the short term. Therefore the goal of this study was to evaluate the pathogenicity of 27 native isolates and 3 strains of entomopathogenic fungi and determine their potential as biological control agents of D. citri by using 2 different bioassay methods. Bioassays were performed under laboratory conditions (26 ± 2 °C, 60 ± 5% RH and 16:8 h L:D) by exposing adult insects to a concentration of 1 × 108 conidia per milliliter using 2 different application methods, i.e., spraying the spores onto the citrus seedlings and spraying the spores directly onto the adult psyllids. The results showed that by direct spraying the adults, HIB-24 (B. bassiana) and HIB-32 (I. fumosorosea) isolates showed the highest mortality (60.66%). Regarding spraying of the seedlings, HIB-19 (I. fumosorosea) showed the highest percentage of mortality (62.02%). The results from this study demonstrate potential for using entomopathogenic fungi in the management of D. citri in México
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