84 research outputs found

    Model based mapping of a novel prototype spark ignition opposed-piston engine

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    Blower-scavenged opposed-piston two-stroke engines possess inherent thermodynamic advantages over four stroke engines. Increasingly well demonstrated in compression ignition form, they are less so in spark ignition form, where there is clearly room for further investigation. Using CONVERGE® CFD, in this work therefore the fuelling requirements of a novel and under-construction small-displacement, two-stroke, spark-ignition, blower-scavenged opposed-piston engine prototype were estimated using three-dimensional computational fluid dynamics simulations. Trapped air mass values generated from motored simulations were used to populate a fuel-agnostic table of speed/scavenge pressure conditions, which will significantly aid the configuration of the engine ECU. This table was tested using targeted fuelled simulations, based on bulk in-cylinder equivalence ratio. Results indicate it was able to predict the required fuel within ±2 % at 1500 rpm, 120/150/180 kPa and 3000 rpm, 150/180 kPa, within ±10 % at 3000 rpm, 120 kPa and 5000 rpm, 180 kPa, and within ±20 % at 5000 rpm, 150 kPa. It performed less well at 5000 rpm, 120 kPa where it overestimated the required fuel by over 43 %, although this was to be expected given the reduced scavenging performance at high speed, low scavenge pressure conditions. The swirl-imparting geometry also appeared to aid in flame front propagation

    Discovery of a mass grave from the Spanish Civil War using GPR and forensic archaeology

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    An estimated 500,000 people died from all causes during the Spanish Civil War between 1936 and 1939, with a further 135,000 killed after the war ended. There are currently over 2,000 known mass burial locations throughout Spain but many more are unknown. This study details the successful search for an unmarked mass grave in mountainous terrain in the Asturias region of Northern Spain. Two approximate locations were known due to eyewitness accounts. A phased site investigation approach was undertaken, which included ground penetrating radar. Results showed a clear geophysical anomaly on 2D GPR profiles. The identified area was subsequently intrusively investigated by forensic archaeologists and human remains were successfully discovered. Careful and sensitive investigations are essential in these approaches where living relatives are involved

    GPR and ERT detection and characterization of a mass burial, Spanish Civil War, Northern Spain

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    Around 27,000 people were killed in the province of Asturias during the Spanish Civil War, with several thousands killed after the war ended. There are currently over 2,000 known mass burial locations throughout Spain, but many more are unknown. Geophysics is a useful tool employed to help in the active attempts to document and improve knowledge about victims from this conflict. This paper details a non-invasive study of the Cementerio de El Salvador, in the city of Oviedo, Northern Spain. Part of the cemetery contains a known mass burial with approximately 1,300 individuals from the Spanish Civil War and post-war repression eras. Multi-frequency near-surface geophysical techniques were undertaken, after permission, to enhance knowledge about which, if any, techniques should be used to detect, delineate and analyse such mass graves. Multi-frequency (250 MHz and 500 MHz) ground-penetrating radar surveys were acquired together with 2D and 3D Electrical Resistivity Tomography datasets. The results have established the limits of the mass grave and improve the knowledge of the internal mass grave structure. The paper also shows the importance of considering the climatic conditions during data acquisition. This has important implications for the successful detection of recent historical mass burials using near-surface geophysics

    Track-based alignment for the BESIII CGEM detector in the cosmic-ray test

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    The Beijing Electron Spectrometer III (BESIII) is a multipurpose detector operating on the Beijing Electron Positron Collider II (BEPCII). After more than ten year's operation, the efficiency of the inner layers of the Main Drift Chamber (MDC) decreased significantly. To solve this issue, the BESIII collaboration is planning to replace the inner part of the MDC with three layers of Cylindrical triple-Gas Electron Multipliers (CGEM). The new features of the CGEM detector will improve the spatial resolution to 130 μ\mum. To meet this goal, a careful calibration of the detector is necessary to fully exploit the potential of the CGEM detector. In all the calibrations, the detector alignment plays an important role to improve the detector precision. The track-based alignment for the CGEM detector with the Millepede algorithm is implemented to reduce the uncertainties of the hit position measurement. Using the cosmic-ray data taken in 2020 with the two layers setup, the displacement of the outer layer with respect to the inner layer is determined by a simultaneous fit applied to more than 160000 tracks. A good alignment precision has been achieved that guarantees the design request could be satisfied in the future. A further alignment will be performed using the combined information of tracks from cosmic-ray and collisions after the CGEM is installed into the BESIII detector

    Tissue culture of ornamental cacti

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    Cacti species are plants that are well adapted to growing in arid and semiarid regions where the main problem is water availability. Cacti have developed a series of adaptations to cope with water scarcity, such as reduced leaf surface via morphological modifications including spines, cereous cuticles, extended root systems and stem tissue modifications to increase water storage, and crassulacean acid metabolism to reduce transpiration and water loss. Furthermore, seeds of these plants very often exhibit dormancy, a phenomenon that helps to prevent germination when the availability of water is reduced. In general, cactus species exhibit a low growth rate that makes their rapid propagation difficult. Cacti are much appreciated as ornamental plants due to their great variety and diversity of forms and their beautiful short-life flowers; however, due to difficulties in propagating them rapidly to meet market demand, they are very often over-collected in their natural habitats, which leads to numerous species being threatened, endangered or becoming extinct. Therefore, plant tissue culture techniques may facilitate their propagation over a shorter time period than conventional techniques used for commercial purposes; or may help to recover populations of endangered or threatened species for their re-introduction in the wild; or may also be of value to the preservation and conservation of the genetic resources of this important family. Herein we present the state-of-the-art of tissue culture techniques used for ornamental cacti and selected suggestions for solving a number of the problems faced by members of the Cactaceae family

    Severe pandemic 2009 H1N1 influenza disease due to pathogenic immune complexes

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    Fil: Monsalvo, Ana Clara. Fundacion INFANT, Buenos Aires; Argentina.Fil: Batalle, Juan P. Fundacion INFANT, Buenos Aires; Argentina.Fil: Lopez, M Florencia. Fundacion INFANT, Buenos Aires; Argentina.Fil: Krause, Jens C. Department of Pediatrics, Vanderbilt University, Nashville, TN; Estados Unidos.Fil: Klemenc, Jennifer. Department of Pediatrics, Vanderbilt University, Nashville, TN; Estados Unidos.Fil: Hernandez, Johanna Zea. . Fundacion INFANT, Buenos Aires; Argentina.Fil: Maskin, Bernardo. Hospital Nacional Prof. Alejandro Posadas, Buenos Aires; Argentina.Fil: Bugna, Jimena. Fundacion INFANT, Buenos Aires; Argentina.Fil: Rubinstein, Carlos. Hospital Dr Federico Abete, Malvinas Argentinas, Buenos Aires; Argentina.Fil: Aguilar, Leandro. Hospital Dr Federico Abete, Malvinas Argentinas, Buenos Aires; Argentina.Fil: Dalurzo, Liliana. Hospital Italiano, Buenos Aires; Argentina.Fil: Libster, Romina. Fundacion INFANT, Buenos Aires; Argentina.Fil: Savy, Vilma. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas; Argentina.Fil: Baumeister, Elsa. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas; Argentina.Fil: Aguilar, Liliana. Hospital Nacional Prof. Alejandro Posadas, Buenos Aires; Argentina.Fil: Cabral, Graciela. Hospital Nacional Prof. Alejandro Posadas, Buenos Aires; Argentina.Fil: Font, Julia. Hospital Nacional Prof. Alejandro Posadas, Buenos Aires; Argentina.Fil: Solari, Liliana. Hospital Nacional Prof. Alejandro Posadas, Buenos Aires; Argentina.Fil: Weller, Kevin P. Department of Pediatrics, Vanderbilt University, Nashville, TN; Estados Unidos.Fil: Johnson, Joyce. Department of Pathology, Vanderbilt University, Nashville, TN; Estados Unidos.Fil: Echavarria, Marcela. Department of Microbiology, CEMIC, Buenos Aires; Argentina.Fil: Edwards, Kathryn M. Department of Pediatrics, Vanderbilt University, Nashville, TN; Estados Unidos.Fil: Chappell, James D. Department of Pathology, Vanderbilt University, Nashville, TN; Estados Unidos.Fil: Crowe, James E. Department of Pediatrics, Vanderbilt University, Nashville, TN; Estados Unidos.Fil: Williams, John V. Department of Pediatrics, Vanderbilt University, Nashville, TN; Estados Unidos.Fil: Melendi, Guillermina A. Fundacion INFANT, Buenos Aires; Argentina.Fil: Polack, Fernando P. Fundacion INFANT, Buenos Aires; Argentina.Pandemic influenza viruses often cause severe disease in middle-aged adults without preexisting comorbidities. The mechanism of illness associated with severe disease in this age group is not well understood. Here we find preexisting serum antibodies that cross-react with, but do not protect against, 2009 H1N1 influenza virus in middle-aged adults. Nonprotective antibody is associated with immune complex-mediated disease after infection. We detected high titers of serum antibody of low avidity for H1-2009 antigen, and low-avidity pulmonary immune complexes against the same protein, in severely ill individuals. Moreover, C4d deposition--a marker of complement activation mediated by immune complexes--was present in lung sections of fatal cases. Archived lung sections from middle-aged adults with confirmed fatal influenza 1957 H2N2 infection revealed a similar mechanism of illness. These observations provide a previously unknown biological mechanism for the unusual age distribution of severe cases during influenza pandemics

    Functional ultrastructure of the plant nucleolus

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    Severe pandemic 2009 H1N1 influenza disease due to pathogenic immune complexes

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    Fil: Monsalvo, Ana Clara. Fundacion INFANT, Buenos Aires; Argentina.Fil: Batalle, Juan P. Fundacion INFANT, Buenos Aires; Argentina.Fil: Lopez, M Florencia. Fundacion INFANT, Buenos Aires; Argentina.Fil: Krause, Jens C. Department of Pediatrics, Vanderbilt University, Nashville, TN; Estados Unidos.Fil: Klemenc, Jennifer. Department of Pediatrics, Vanderbilt University, Nashville, TN; Estados Unidos.Fil: Hernandez, Johanna Zea. . Fundacion INFANT, Buenos Aires; Argentina.Fil: Maskin, Bernardo. Hospital Nacional Prof. Alejandro Posadas, Buenos Aires; Argentina.Fil: Bugna, Jimena. Fundacion INFANT, Buenos Aires; Argentina.Fil: Rubinstein, Carlos. Hospital Dr Federico Abete, Malvinas Argentinas, Buenos Aires; Argentina.Fil: Aguilar, Leandro. Hospital Dr Federico Abete, Malvinas Argentinas, Buenos Aires; Argentina.Fil: Dalurzo, Liliana. Hospital Italiano, Buenos Aires; Argentina.Fil: Libster, Romina. Fundacion INFANT, Buenos Aires; Argentina.Fil: Savy, Vilma. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas; Argentina.Fil: Baumeister, Elsa. ANLIS Dr.C.G.Malbrán. Instituto Nacional de Enfermedades Infecciosas; Argentina.Fil: Aguilar, Liliana. Hospital Nacional Prof. Alejandro Posadas, Buenos Aires; Argentina.Fil: Cabral, Graciela. Hospital Nacional Prof. Alejandro Posadas, Buenos Aires; Argentina.Fil: Font, Julia. Hospital Nacional Prof. Alejandro Posadas, Buenos Aires; Argentina.Fil: Solari, Liliana. Hospital Nacional Prof. Alejandro Posadas, Buenos Aires; Argentina.Fil: Weller, Kevin P. Department of Pediatrics, Vanderbilt University, Nashville, TN; Estados Unidos.Fil: Johnson, Joyce. Department of Pathology, Vanderbilt University, Nashville, TN; Estados Unidos.Fil: Echavarria, Marcela. Department of Microbiology, CEMIC, Buenos Aires; Argentina.Fil: Edwards, Kathryn M. Department of Pediatrics, Vanderbilt University, Nashville, TN; Estados Unidos.Fil: Chappell, James D. Department of Pathology, Vanderbilt University, Nashville, TN; Estados Unidos.Fil: Crowe, James E. Department of Pediatrics, Vanderbilt University, Nashville, TN; Estados Unidos.Fil: Williams, John V. Department of Pediatrics, Vanderbilt University, Nashville, TN; Estados Unidos.Fil: Melendi, Guillermina A. Fundacion INFANT, Buenos Aires; Argentina.Fil: Polack, Fernando P. Fundacion INFANT, Buenos Aires; Argentina.Pandemic influenza viruses often cause severe disease in middle-aged adults without preexisting comorbidities. The mechanism of illness associated with severe disease in this age group is not well understood. Here we find preexisting serum antibodies that cross-react with, but do not protect against, 2009 H1N1 influenza virus in middle-aged adults. Nonprotective antibody is associated with immune complex-mediated disease after infection. We detected high titers of serum antibody of low avidity for H1-2009 antigen, and low-avidity pulmonary immune complexes against the same protein, in severely ill individuals. Moreover, C4d deposition--a marker of complement activation mediated by immune complexes--was present in lung sections of fatal cases. Archived lung sections from middle-aged adults with confirmed fatal influenza 1957 H2N2 infection revealed a similar mechanism of illness. These observations provide a previously unknown biological mechanism for the unusual age distribution of severe cases during influenza pandemics
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