Parasites Associated with Thirteen-lined Ground Squirrels (Spermophilus tridecemlineatus Mitchill) from Ames, Iowa

A total of 19, thirteen-lined ground squirrels (Spermophilus tridecemlineatus) were examined for parasites from two locations in Ames, Iowa. Parasites found and their respective prevalence included Androlaelaps fahrenholzi (47.4%), an unidentified non-parasitic mesostigmatic mite (21.1 %), Ixodes sculptus (52.6%), Opisocrostis bruneri (26. 3%), a skin bot believed to be Cuterebra sp. (5.3%), Monocystis sp. (18.8%), Eimeria citelli, (81.3%) and E. bilamellata (18.8%). Helminths were not found, nor were antibodies to Toxoplasma gondii

Quantum molecular dynamics simulations for the nonmetal-to-metal transition in fluid helium

We have performed quantum molecular dynamics simulations for dense helium to study the nonmetal-to-metal transition at high pressures. We present new results for the equation of state and the Hugoniot curve in the warm dense matter region. The optical conductivity is calculated via the Kubo-Greenwood formula from which the dc conductivity is derived. The nonmetal-to-metal transition is identified at about 1 g/ccm. We compare with experimental results as well as with other theoretical approaches, especially with predictions of chemical models.Comment: 4 pages, 5 figure

Making sense of text: artificial intelligence-enabled content analysis

Purpose: The purpose of this paper is to introduce, apply and compare how artificial intelligence (AI), and specifically the IBM Watson system, can be used for content analysis in marketing research relative to manual and computer-aided (non-AI) approaches to content analysis. Design/methodology/approach: To illustrate the use of AI-enabled content analysis, this paper examines the text of leadership speeches, content related to organizational brand. The process and results of using AI are compared to manual and computer-aided approaches by using three performance factors for content analysis: reliability, validity and efficiency. Findings: Relative to manual and computer-aided approaches, AI-enabled content analysis provides clear advantages with high reliability, high validity and moderate efficiency. Research limitations/implications: This paper offers three contributions. First, it highlights the continued importance of the content analysis research method, particularly with the explosive growth of natural language-based user-generated content. Second, it provides a road map of how to use AI-enabled content analysis. Third, it applies and compares AI-enabled content analysis to manual and computer-aided, using leadership speeches. Practical implications: For each of the three approaches, nine steps are outlined and described to allow for replicability of this study. The advantages and disadvantages of using AI for content analysis are discussed. Together these are intended to motivate and guide researchers to apply and develop AI-enabled content analysis for research in marketing and other disciplines. Originality/value: To the best of the authors' knowledge, this paper is among the first to introduce, apply and compare how AI can be used for content analysis

Facies analysis and stratigraphic assignment of Middle Jurassic unnamed fluvial deposits in the Southern Mendoza Neuquén Basin

Se realizaron estudios sedimentológico-estratigráficos en los depósitos fluviales innominados del Jurásico Medio de la Cuenca Neuquina surmendocina, que afloran en el anticlinal de Malargüe y Bardas Blancas. En el primero de ellos se reconocieron facies de sistemas fluviales entrelazados gravo-arenosos que se apilan en tres secuencias depositacionales mostrando un decrecimiento paulatino en el espacio de acomodación, en tanto que en el segundo se reconocieron facies de sistemas fluviales anastomosados que se agrupan en dos secuencias depositacionales con un incremento progresivo del espacio de acomodación. En el anticlinal de Malargüe las relaciones estratigráficas y el patrón de apilamiento sugiere la asignación de estos depósitos al Bajociano tardío-Bathoniano y su correlación con la Formación Lajas, por lo que se propone la denominación de Formación Puesto Pacheco nov. nom., con su estratotipo en la sección del arroyo Loncoche. En el área de Bardas Blancas la presencia de clastos de calizas y fragmentos de ostras en la base de la unidad permitiría establecer que los depósitos fluviales se habrían depositado con posterioridad a la discordancia Intracaloviana. En este sector se le asigna una edad Caloviana media - tardía y se los asigna a la Formación Lotena.Stratigraphic-sedimentological studies were performed on Middle Jurassic unnamed fluvial deposits of the Southern Mendoza Neuquén Basin, cropping out in the Malargüe anticline and Bardas Blancas. In the first area we recognized braided fluvial systems facies stacked in three depositional sequences showing a gradual decrease in the accommodation space, whereas in the second we recognized anastomosing fluvial systems facies grouped into two depositional sequences with a progressive increase in the accommodation space. Stratigraphic relationships and stacking pattern in the Malargüe anticline suggests the assignment of this unit to the late Bajocian-Bathonian and its correlation with the Lajas Formation, so the name of Puesto Pacheco Formation nov. nom. is proposed, with its stratotype in the Loncoche creek section. In the Bardas Blancas area the presence of limestone clasts and oysters fragments at the base of the unit, would establish that unnamed fluvial deposits would have been deposited after the Intracallovian unconformity. In this area it is given a middle-late Callovian age and the assignment to the Lotena Formation.Fil: Kietzmann, Diego Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos; ArgentinaFil: Palma, Ricardo Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos; ArgentinaFil: Ferreyra, Teresita M. A.. YPF - Tecnología; Argentin

Las tempestitas peloidales de la Formación Vaca Muerta (Tithoniano-Valanginiano) en el sector surmendocino de la Cuenca Neuquina, Argentina

Se analizan los depósitos de tormenta de dos secciones estratigráficas de la Formación Vaca Muerta (Tithoniano-Valanginiano) en el área de Bardas Blancas, sur de la provincia de Mendoza. Estos depósitos incluyen: a) depósitos con estratificación entrecruzada de bajo ángulo; b) depósitos con estratificación entrecruzada hummocky de pequeña y gran escala; y c) depósitos laminados con gradación normal intralámina. Las secuencias completas con HCS están compuestas por tres unidades (Sa, Sb y Sc) asociadas al evento de tormenta y una unidad que incluye depósitos de post-tormenta y de buen tiempo (Sd). La comparación con ejemplos actuales y ejemplos del registro, permite estimar un rango batimétrico de 25 a 50 m para los depósitos con estratificación entrecruzada hummocky. Asimismo se discuten posibles orígenes alternativos relacionados con inestabilidades en la interfase de la picnoclina y los efectos de la compactación sobre la preservación de las texturas y estructuras primarias de los depósitos de la Formación Vaca Muerta

Estratigrafía y análisis de facies de la Formación Vaca Muerta en el área de El Trapial

La importancia de los análisis estratigráficos, de facies y sedimentológicos para evaluar el potencial de un reservorio no convencional para identificar las zonas más favorables para la prospección y explotación de hidrocarburos.Fil: González Tomassini, Federico. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Geología; ArgentinaFil: Kietzmann, Diego Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Estudios Andinos "Don Pablo Groeber". Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos ; ArgentinaFil: Fantin, Manuel A.. Chevron; ArgentinaFil: Crousse, Luisa C.. Chevron; ArgentinaFil: Reijenstein, Hernán M.. Chevron Latin America Business; Estados Unido

New biostratigraphic data from the Callovian-Oxfordian La Manga Formation, Neuquén Basin, Argentina: Evidence from an ammonite condensed level

The La Manga Formation constitutes most of the sedimentary record of the Callovian-Oxfordian in the Neuquén Basin. This stratigraphic unit represents the middle part of the Lotena Mesosequence, which is dominated by carbonates with interbedded shales, marls, and occasional sandstones. Based on detailed stratigraphic work in the stratotype section (La Manga Creek, Mendoza), the depositional environments and the sea-level history of the La Manga Formation have been interpreted. Petrographic and field observations led to identification of nine facies distributed in two informal units. Unit 1 was deposited on a outer ramp setting, while deposition of unit 2 took place in the intertidal-supratidal environments. A condensed level close to the base of unit 1 has yielded Rehmannia sp., Rehmannia cf. paucicostata (Tornq.) and Homoeoplanulites sp., from the Lower Callovian Bodenbenderi-Proximum Zones, and Peltoceratoides sp. and Rursiceras sp. from the Upper Callovian and also in the Lower Oxfordian Peltoceratoides-Parawedekindia Zone. The condensed level is overlain by a Middle Oxfordian succession characterized by Perisphinctes (?Arisphinctes) sp., Perisphinctes (?Kranaosphinctes) sp., Mirosphinctes sp., Perisphinctes (?Antilloceras) cf. prophetae Gygi & Hill., Perisphinctes (?Otosphinctes) sp., Perisphinctes (?Subdiscosphinctes) sp., and Perisphinctes (?Kranaosphinctes) cf. decurrens (Buck.) of the Perisphinctes-Araucanites Zone, which was correlated with the upper part of the Cordatum Standard Zone to the Transversarium Standard Zone, and probably to the lower part of the Bifurcatus Standard Zone. Unit 2 has yielded small Mirosphinctes sp., indicating an Oxfordian age. The sharp contact between the outer ramp facies of unit 1 and the overlying intertidal-supratidal facies of unit 2 can be interpreted as the result of an abrupt fall (forced regression) of the relative sea level during the end of Middle Oxfordian or Upper Oxfordian. These results could be used for comparison with other localities in the Neuquén Basin providing additional data for Lower Callovian-Middle Oxfordian deposits

Palaeoenvironmental significance of middle Oxfordian deep marine deposits from La Manga Formation, Neuquén Basin, Argentina

[EN] The Callovian-Oxfordian of the Neuquén Basin (Argentina) is characterized by an extensive marine carbonate system (La Manga Formation) with a predominance of shallow and middle ramp deposits, although locally in tectonically controlled settings, deeper deposits also formed. These middle Oxfordian deeper deposits consist of mudstone-wackestone carbonates alternating with black shales and show marked centimetre-scale rhythmicity, probably controlled by the Earth’s orbit parameters, mainly precession and eccentricity. The present study was designed to examine these deposits in terms of their sedimentology, geochemistry, and small-scale stratigraphy in Arroyo Los Blancos, southern Mendoza Province, where they are exceptionally well exposed and preserved. Results indicate that the sediments were deposited in an anoxic to dysoxic, relatively deep, sea-floor environment as revealed by the presence of: a) organic-rich shales, b) undisrupted lamination in most facies, c) pyrite framboids, and d) absence or scarcity of trace fossils and benthic fauna. Thin beds of graded wackestone-packstone and accumulations of thin shells of Bositra bivalves indicate sporadic reworking of the sea floor by weak currents. Organic petrology, Rock-Eval pyrolysis and thermal maturity indicators were used to characterize TOC and different types of organic matter. Low pyrolysis S yields along with low hydrogen indices suggest poor kerogen convertibility. Vitrinite reflectance (%Ro) ranged from 2.39 to 2.97 with an average of 2.70. The thermal alteration index (TAI) was 4+(5), indicating overmaturity. A tectono-sedimentary model is proposed for these deposits. According to this model, the relatively deep, organic-matter rich facies of La Manga Formation would have been deposited in the deepest zones of topographic lows controlled by tilting and differential subsidence of tectonic blocks bounded by normal faults.These faults were probably inherited from previous extensional tectonics of Late Triassic - Early Jurassic age.[ES] El Calloviense-Oxfordiense en el norte de la Cuenca Neuquina (Argentina) estuvo caracterizado por el desarrollo de un amplio sistema de rampa carbonatada (Formación La Manga) en el que predominaron los depósitos de rampa media y somera aunque localmente, y debido a control tectónico, pudieron acumularse depósitos más profundos. Estos depósitos, de edad Oxfordiense medio, están expuestos y preservados excepcionalmente en la zona de Arroyo Los Blancos, al sur de la provincia de Mendoza, y su estudio sedimentológico, geoquímico y estratigráfico representan el objetivo de este trabajo. Consisten en carbonatos (mudstone-wackestone) con acumulaciones de finas conchas de bivalvos de tipo Bositra que indican retrabajamientos esporádicos del sustrato marino debido a corrientes de baja intensidad. Se han caracterizado diferentes tipos de materia orgánica y TOC mediante petrología orgánica, Rock-Eval Pyrolisis e indicadores de madurez térmica. Los bajos valores en el campo del S unido al también bajo índice de H sugieren una baja convertibilidad de Kerógeno. La reflectancia de la vitrinita (%Ro) tiene un rango que oscila entre 2,39 y 2,97, con una media de 2,70, mientras que el índice de alteración térmico (TAI) es de 4+(5) indicando sobremaduración. Se propone también un modelo tectono-sedimentario para estos depósitos. En este modelo, estas facies relativamente profundas y ricas en materia orgánica de la Formación La Manga estarían depositadas en la parte más deprimida de bajos topográficos controlados por una subsidencia diferencial y de pulsos en bloques marcados por fallas normales heredadas probablemente de una tectónica extensional durante el Triásico Superior-Jurásico Inferior.Peer reviewe

A systematic literature review of the use of social media for business process management

In today’s expansion of new technologies, innovation is found necessary for organizations to be up to date with the latest management trends. Although organizations are increasingly using new technologies, opportunities still exist to achieve the nowadays essential omnichannel management strategy. More precisely, social media are opening a path for benefiting more from an organization’s process orientation. However, social media strategies are still an under-investigated field, especially when it comes to the research of social media use for the management and improvement of business processes or the internal way of working in organizations. By classifying a variety of articles, this study explores the evolution of social media implementation within the BPM discipline. We also provide avenues for future research and strategic implications for practitioners to use social media more comprehensively

Warming Up Density Functional Theory

Density functional theory (DFT) has become the most popular approach to electronic structure across disciplines, especially in material and chemical sciences. Last year, at least 30,000 papers used DFT to make useful predictions or give insight into an enormous diversity of scientific problems, ranging from battery development to solar cell efficiency and far beyond. The success of this field has been driven by usefully accurate approximations based on known exact conditions and careful testing and validation. In the last decade, applications of DFT in a new area, warm dense matter, have exploded. DFT is revolutionizing simulations of warm dense matter including applications in controlled fusion, planetary interiors, and other areas of high energy density physics. Over the past decade or so, molecular dynamics calculations driven by modern density functional theory have played a crucial role in bringing chemical realism to these applications, often (but not always) with excellent agreement with experiment. This chapter summarizes recent work from our group on density functional theory at non-zero temperatures, which we call thermal DFT. We explain the relevance of this work in the context of warm dense matter, and the importance of quantum chemistry to this regime. We illustrate many basic concepts on a simple model system, the asymmetric Hubbard dimer