1,676 research outputs found
Ghostly presences in H.P. Lovecraft’s “Cool Air” and The Case of Charles Dexter Ward
H.P. Lovecraft (1890-1937) is a writer characterized for his mixture of genres –what is known as the weird tale– that borrows influences from gothic fiction, fantasy, horror and science fiction. This amalgam of styles and genres results in the unusual apparition of classical horror figures (vampires, zombies, ghosts) that are filtered through a very original view. It is the goal of this chapter to analyze how Lovecraft dealt with ghostly presences in his tales. Through the review of theoretical approaches to ghosts and specters, I will focus my attention on two texts, “Cool Air” and The Case of Charles Dexter Ward, in order to unravel the connections that seemingly detached characters might have with the classical gothic ghost
Potamoplancton en la cuenca media del río Cuarto(Córdoba, Argentina)
El objetivo de esta investigación es analizar la composición y abundancia de las algas en transporte y su relación con variables ambientales y microbiol'ogicas en la zona de llanura aluvial ancha de la cuenca del río Cuarto. Se consideraron cinco períodos de muestreo: primavera 1999, verano 2000, otoño 2000, invierno 2000 y primavera 2000. Se seleccionaron 5 localidades en el trayecto longitudinal del río Cuarto: Tres Acequias, ElMogote (tramo urbano), Puente Antártida Argentina, Cloacas (sector de efluvios cloacales de la ciudad) y Paso del Durazno. Se recolectaron 25 muestras para el estudio biológico, 25 para el análisis microbiológico y 25 para determinar nutrientes. Las muestras de fitoplancton se obtuvieron por filtración de 100 litros de agua a través de una red de plancton de 25 μm de diámetro de poro y simultáneamente se registraron parámetros fisicoquímicos e hidráulicos. Se determinaron un total de 142 taxa: 6 son Cyanophyceae, 9 son Chlorophyceae, 1 Euglenophyceae y 127 son Bacillariophyceae. La densidad algal osciló entre 215.09 células/ml en Paso del Durazno, en primavera 1999 y 0.1 células/ml en Tres Acequias, en otoño 2000. La m'axima densidad de la clase Bacillariophyceae se registró en primavera 1999 en Paso del Durazno con 106.82 células/ml. La máxima y mínima diversidad se registró en Las Cloacas con 4.49 bits/cél en verano y 2.57 bits/cél en invierno respectivamente. La equidad varió entre 0.45 en primavera 1999 en Paso del Durazno y 0.95 en otoño para el mismo sitio de muestreo. Los resultados microbiológicos obtenidos infieren la importancia del vuelco de los efluentes cloacales al curso fluvial, evidenciado también por la presencia de especies algales de mayor valor sapróbico. Los valores del Índice Diatómico de Sladecek caracteriza al tramo en estudio dentro del rango β-mesosaprobios, contaminación moderada a alta, para los sitios Tres Acequias, El Mogote y Puente Antártica Argentina y polisaprobios, contaminación alta, en el sector Cloacas y Paso del Durazno.The aim of this research is to analyse the flowing algal composition and abundance as well as its relationship with the environmental and microbiological variables throughout the broad alluvial plain of the Cuarto River basin. Five sampling periods were considered: spring of 1999, summer of 2000, fall of 2000, winter 2000 and spring of 2000. Five sites were selected along the Cuarto River: Tres Acequias, El Mogote (urban stretch), Puente Antártida Argentina, Las Cloacas (city sewages outflow), and Paso del Durazno. Twenty five samples were collected for the biological study, 25 samples for microbiological analysis and 25 samples for nutrients determination. Phytoplankton samples were obtained by filtrating 100 L of water through a 25 μm pored plankton-net, with the physicochemical and hydraulic patterns being registered at the same time. A total of 142 taxa were found: 6 Cyanophyceae, 9 Chlorophyceae, 1 Euglenophyceae and 127 Bacillariophyceae. The algal density ranged between 215.09 cells/ml in the spring of 1999 at Paso del Durazno and 0.1 cells/ml in the fall of 2000 at Tres Acequias. The greatest density for the Bacillariophyceae class was registered in the spring of 1999 at Paso del Durazno with 106 cells/ml. The maximum and minimum diversity was registered at Las Cloacas with 4.49 bits/cell in summer and 2.57 bits/cell in winter, respectively. The equity varied between 0.45 in the spring of 1999 at Paso del Durazno and 0.95 in the fall of 2000 for the same sampling site. The microbiological results show an important effect caused by the sewage outflow, which is also indicated by the presence of algae with a high saprobic value. The Sladecek Diatomic Index values indicate that the studied river section show β-ranging mesoprobes and medium to high pollution level for Tres Acequias, El Mogote and Puente Antártida Argentina sampling sites, and polysaprobes and high pollution level for Las Cloacas and Paso del Durazno
Perfil fenólico de aceites de oliva vírgenes obtenidos de selecciones avanzadas en un programa de mejora
The evaluation of the phenolic composition in advanced selections in breeding programs constitutes the first approach for selecting genotypes with improved olive oil quality. In this work, the influence of genotype and ripening index on the phenolic profile of olive oils from advanced selections in comparison to their genitors was studied. Fruit samples were collected in genotypes from crosses between ‘Arbequina’ × ‘Picual’, ‘Picual’ × ‘Arbequina’ and ‘Frantoio’ × ‘Picual’ at five dates from 1st October to 26th November 2009. Characterization of the phenolic profile was performed by liquid–liquid extraction with 60:40 (v/v) methanol–water and subsequent chromatographic analysis with absorption and fluorescence detection in a sequential configuration. A dual effect of genotype and fruit ripening on the phenolic profile has been observed with more pronounced genetic influence in both total (34.73% and 20.45%, respectively) and individual phenols (16.99% to 49.25% and 1.58% to 23.77%, respectively). A higher degree of variability between genotypes at early ripening stages was also observed (p<0.05). The obtained results also allow identification of selections with high content of total and individual phenols. These results suggest a strategy based on early harvesting of fruits (at the first three ripening indexes) for better comparison and selection of genotypes in further crosses in olive breeding programs aiming at improving the quality of virgin olive oil.La evaluación de la composición fenolica en selecciones avanzadas en programas de mejora constituye el primer paso para la selección de genotipos cuyos aceites son de mejor calidad. Se ha estudiado la influencia del genotipo y del índice de madurez en el perfil fenólico del aceite de oliva de selecciones avanzadas en comparación con sus genitores. Se recogieron muestras de genotipos obtenidos de cruzamientos entre 'Arbequina' × 'Picual', 'Picual' × 'Arbequina' y 'Frantoio' × 'Picual' en cinco fechas entre el 1 de octubre y el 26 noviembre de 2009. Se realizó la caracterización del perfil fenólico por extracción líquido–líquido con metanol–agua al 60:40 (v/v) seguido de un análisis cromatográfico con detección por absorción y fluorescencia en una configuración secuencial. Los resultados obtenidos mostraron un mayor grado de variabilidad entre genotipos en las primeras etapas de maduración de los frutos (p<0.05), así como el efecto de la madurez de los frutos y del genotipo en el perfil fenólico, con una influencia genética más pronunciada tanto para fenoles totales (34.73% and 20.45%, respectivamente) como individuales (entre 16.99% y 49.25% y entre 1.58% y 23.77%, respectivamente). Los resultados obtenidos han permitido la identificación de selecciones con alto contenido en fenoles totales e individuales. Ambos resultados sugieren una estrategia basada en la evaluación de los fenoles totales e individuales en las primeras etapas de la maduración para comparar y seleccionar genotipos en programas de mejora por cruzamiento encaminados a mejorar la calidad del aceite de oliva virgen
Reconocimiento del virus de la mancha anular de la papaya (Carica papaya L.) en Colombia.
Basado en la tesis de C. Sánchez de Luque: El virus de la mancha anular de la papaya en Colombia (Doc 600)Papaya-Carica papaya L. - mamo
The Partition Function of Multicomponent Log-Gases
We give an expression for the partition function of a one-dimensional log-gas
comprised of particles of (possibly) different integer charge at inverse
temperature {\beta} = 1 (restricted to the line in the presence of a
neutralizing field) in terms of the Berezin integral of an associated non-
homogeneous alternating tensor. This is the analog of the de Bruijn integral
identities [3] (for {\beta} = 1 and {\beta} = 4) ensembles extended to
multicomponent ensembles.Comment: 14 page
What can metazoan parasites reveal about the taxonomy of Scomber japonicus Houttuyn in the coast of South America and Madeira Islands?
The metazoan parasites of four populations of the chub mackerel Scomber japonicus were
analysed from two localities in the Atlantic Ocean (Madeira Islands, Portugal, and Rio de
Janeiro, Brazil) and two localities in the Pacific Ocean (Callao, Peru, and Antofagasta, Chile),
collected during 2002 and 2003. A total of 373 fish specimens were studied and 34 metazoan
parasite species were obtained. Parasites identified from the populations of chub mackerel
studied could be separated into three categories: parasites with a wide distribution, present in
the Pacific and Atlantic, parasites proper of the Pacific Ocean and parasites proper of the
Atlantic Ocean. The analyses of some highly specific parasites of the genus Scomber (i.e.
monogeneans of the genus Kuhnia and didymozoid digeneans) strongly suggest the need for
a revision of the taxonomic status of chub mackerels from the Atlantic and Pacific coast of
America. The results demonstrated the usefulness of parasites as adequate tools to clarify the
taxonomic status of their hosts.We thank R. Poulin (University of Otago, New Zealand) for reading and commenting on an early draft of the manuscript. J.L.L. was supported by a fellowship (N° 200906-2005.4) of the Conselho Nacional de Desenvolvimento Cientı´fico e Tecnolo´ gico (CNPq) of Brazil for postdoctoral research in the Department of Zoology at the
University of Otago, New Zealand. G. Costa was supported by Portuguese Foundation
of Science and Technology, programme POCTI.info:eu-repo/semantics/publishedVersio
Algas fitoplanctónicas del río Piedra Blanca (Córdoba, Argentina) y su relación con los factores ambientales
María Elisa Luque y Ana L. Martínez de Fabricius. 2003. Distribución temporal de algas fitoplanctónicas en el río Piedra Blanca (Córdoba, Argentina). Lilloa 42 (1-2). El objetivo de esta investigación fue analizar las variaciones temporales en la composición y abundancia de las algas planctónicas en el río Piedra Blanca, así como la influencia de los factores ambientales sobre los biológicos durante un ciclo anual. Las muestras fueron recolectadas mensualmente desde junio de 1988 a junio de 1989, en un punto seleccionado del río Piedra Blanca. Se registraron simultáneamente parámetros físicos e hidráulicos. Se identificaron 220 taxa, 10 Cyanophyceae, 36 Chlorophyceae, 171 Bacillariophyceae, 1 Euglenophyceae y 2 Dinophyceae. La densidad del fitoplancton osciló entre 2 org.ml-1 en el mes de junio de 1988 y 425 org.ml-1en junio de 1989. La clase Bacillariophyceae contribuyó con la mayor densidad representando un 93%. Las especies Cocconeis placentula var. lineata, Cocconeis placentula var. euglypta, Melosira varians y Synedra ulna constituyeron el mayor aporte a la densidad fitoplanctónica. Las Chlorophyceae predominaron durante los meses de verano. El pH, conductividad y sólidos disueltos permitieron explicar las variaciones de número de especies y densidad de organismos
A Portable Microwave Scanner for Brain Stroke Monitoring: Design, Implementation and Experimental Validation
This paper presents the design, the realization, and the experimental assessment of a novel portable microwave scanner prototype for brain stroke monitoring. The device employs a 22-antenna-array, placed conformal to the upper head part, composed of compact, flexible, and custom-made antennas working at around 1 GHz. The validation includes the monitoring of an experimentally emulated evolving hemorrhagic stroke. The progression of the medical condition is emulated via a non-static phantom (custom-shape balloon), derived from medical images, and a single-cavity 3-D anthropomorphic head phantom. The phantoms are filled with liquids mimicking the dielectric properties of the hemorrhage and the average brain tissues, respectively. The imaging-based follow-up is approached using a differential scheme that receives the scattering matrices, taken at two different instants, and exploits the distorted Born approximation to form the image in real-time. The kernel of the imaging algorithm is computed through accurate numerical models. The results verify the capabilities of the system to assess the continuous evolution of the stroke
MicroRNA signature from extracellular vesicles of HCV/HIV co-infected individuals differs from HCV mono-infected
Hepatitis C virus (HCV) coinfection with human immunodeficiency virus (HIV) has a detrimental impact on disease progression. Increasing evidence points to extracellular vesicles (EVs) as important players of the host-viral cross-talk. The microRNAs (miRNAs), as essential components of EVs cargo, are key regulators of normal cellular processes and also promote viral replication, viral pathogenesis, and disease progression. We aimed to characterize the plasma-derived EVs miRNA signature of chronic HCV infected and HIV coinfected patients to unravel the molecular mechanisms of coinfection. EVs were purified and characterized from 50 plasma samples (21 HCV mono- and 29 HCV/HIV co-infected). EV-derived small RNAs were isolated and analyzed by massive sequencing. Known and de novo miRNAs were identified with miRDeep2. Significant differentially expressed (SDE) miRNA identification was performed with generalized linear models and their putative dysregulated biological pathways were evaluated. Study groups were similar for most clinical and epidemiological characteristics. No differences were observed in EVs size or concentration between groups. Therefore, HCV/HIV co-infection condition did not affect the concentration or size of EVs but produced a disturbance in plasma-derived EVs miRNA cargo. Thus, a total of 149 miRNAs were identified (143 known and 6 de novo) leading to 37 SDE miRNAs of which 15 were upregulated and 22 downregulated in HCV/HIV co-infected patients. SDE miRNAs regulate genes involved in inflammation, fibrosis, and cancer, modulating different biological pathways related to HCV and HIV pathogenesis. These findings may help to develop new generation biomarkers and treatment strategies, in addition to elucidate the mechanisms underlying virus-host interaction. KEY MESSAGES: HCV and HCV/HIV displayed similar plasma-EV size and concentration. EVs- derived miRNA profile was characterized by NGS. 37 SDE miRNAs between HCV and HCV/HIV were observed. SDE miRNAs regulate genes involved in inflammation, fibrosis and cancer.Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. This work has been supported by grants from (1) Institute of Health Carlos III, Spain [PI18CIII/00020/ to AFR], (2) PID2021–126781OB-I00 funded by MCIN/AEI/10.13039/501100011033 and by “ERDF A way of making Europe”, (3) The SPANISH AIDS Research Network RD16CIII/0002/0002 - ISCIII – FEDER, (4) Centro de Investigación en Red en Enfermedades Infecciosas (CIBERINFEC) CB21/13/00044, (5) the National Agency for Scientific and Technology Promotion (ANPCyT) (PICT 2017 Nº713), and (6) the National Research Council (CONICET, PIP 2021-2023). V.C. received funding form the Asociación Universitaria Iberoamericana de Postgrado (AUIP) for the Academic Mobility Scholarship Program. P.V., E.D.M., and M.V.P. are members of the CONICET-Research Career Program. V.C. is a fellow from ANPCyT. The funder’s had no role in the study design, data collection and analysis, decision to publish, or the preparation of the manuscript.S
Probing photo-ionization: simulations of positive streamers in varying N2:O2 mixtures
Photo-ionization is the accepted mechanism for the propagation of positive
streamers in air though the parameters are not very well known; the efficiency
of this mechanism largely depends on the presence of both nitrogen and oxygen.
But experiments show that streamer propagation is amazingly robust against
changes of the gas composition; even for pure nitrogen with impurity levels
below 1 ppm streamers propagate essentially with the same velocity as in air,
but their minimal diameter is smaller, and they branch more frequently.
Additionally, they move more in a zigzag fashion and sometimes exhibit a
feathery structure. In our simulations, we test the relative importance of
photo-ionization and of the background ionization from pulsed repetitive
discharges, in air as well as in nitrogen with 1 ppm O2 . We also test
reasonable parameter changes of the photo-ionization model. We find that photo-
ionization dominates streamer propagation in air for repetition frequencies of
at least 1 kHz, while in nitrogen with 1 ppm O2 the effect of the repetition
frequency has to be included above 1 Hz. Finally, we explain the feather-like
structures around streamer channels that are observed in experiments in
nitrogen with high purity, but not in air.Comment: 12 figure
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