901 research outputs found

    Application of High-precision Timing Systems to Distributed Survey Systems

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    In any hydrographic survey system that consists of more than one computer, one of the most difficult integration problems is to ensure that all components maintain a coherent sense of time. Since virtually all modern survey systems are of this type, timekeeping and synchronized timestamping of data as it is created is of significant concern. This paper describes a method for resolving this problem based on the IEEE 1588 Precise Time Protocol (PTP) implemented by hardware devices, layered with some custom software called the Software Grandmaster (SWGM) algorithm. This combination of hardware and software maintains a coherent sense of time between multiple ethernet-connected computers, on the order of 100 ns (rms) in the best case, of the timebase established by the local GPS-receiver clock. We illustrate the performance of this techniques in a practical survey system using a Reson 7P sonar processor connected to a Reson 7125 Multibeam Echosounder (MBES), integrated with an Applanix POS/MV 320 V4 and a conventional data capture computer. Using the timing capabilities of the PTP hardware implementations, we show that the timepieces achieve mean (hardware based) synchronization and timestamping within 100-150 ns (rms), and that the data created at the Reson 7P without hardware timestamps has a latency variability of 28 µs (rms) due to software constraints within the capture system. This compares to 288 ms (rms) using Reson’s standard hybrid hardware/software solution, and 13.6 ms (rms) using a conventional single-oscillator timestamping model

    Criminal narrative experience: relating emotions to offence narrative roles during crime commission

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    A neglected area of research within criminality has been that of the experience of the offence for the offender. The present study investigates the emotions and narrative roles that are experienced by an offender while committing a broad range of crimes and proposes a model of Criminal Narrative Experience (CNE). Hypotheses were derived from the Circumplex of Emotions (Russell, 1997), Frye (1957), Narrative Theory (McAdams, 1988) and its link with Investigative Psychology (Canter, 1994). The analysis was based on 120 cases. Convicted for a variety of crimes, incarcerated criminals were interviewed and the data were subjected to Smallest Space Analysis (SSA). Four themes of Criminal Narrative Experience (CNE) were identified: Elated Hero, Calm Professional, Distressed Revenger and Depressed Victim in line with the recent theoretical framework posited for Narrative Offence Roles (Youngs & Canter, 2012). The theoretical implications for understanding crime on the basis of the Criminal Narrative Experience (CNE) as well as practical implications are discussed

    Expressive and Instrumental Offending: Reconciling the Paradox of Specialisation and Versatility

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    Although previous research into specialisation has been dominated by the debate over the existence of specialisation versus versatility, it is suggested that research needs to move beyond the restrictions of this dispute. The current study explores the criminal careers of 200 offenders based on their criminal records, obtained from a police database in the North West of England, aiming to understand the patterns and nature of specialisation by determining the presence of differentiation within their general offending behaviours and examining whether the framework of Expressive and Instrumental offending styles can account for any specialised tendencies that emerge. Fifty-eight offences were subjected to Smallest Space Analysis. Results revealed that a model of criminal differentiation could be identified and that any specialisation is represented in terms of Expressive and Instrumental offending styles

    High-Precision, High-Accuracy Timekeeping in Distributed Survey Systems

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    Accurate and precise timekeeping between computers in a distributed survey system is essential to ensure adequate data quality, especially with Multibeam Echosounders (MBES) which can otherwise suffer from significant motion artefacts. We show that clock synchronisation on the order of 100-150ns (rms) is readily achievable in a modern MBES-based survey system utilising an Ethernet-based time synchronisation mechanism and some custom timekeeping software. We also show that improving the timekeeping eliminates motion artefacts in the observed bathymetry, and simplifies the patch-test procedure.Para asegurar una calidad adecuada de los datos es esencial una exacta y precisa mantencion de la hora entre ordenadores en un sistema de levantamiento distribuido, especialmente con Sondadores Acusticos Multihaz (MBES), que sino pueden experimentar las consecuencias de un significativo movimiento de sus artefactos. Mostramos que la sincronizaci6n de un reloj en el orden de 100-150ns (rms) puede llevarse a cabo facilmente en un sistema moderno de levantamientos efectuados mediante MBES, utilizando un mecanismo Ethernet basado en la sincronizacion del tiempo y en algun programa de mantencion de la hora adaptado. Tambien mostramos que mejorando la mantencion de la hora se elimina el movimiento de los artefactos en la batimetria observada, y simplifica el procedimiento de pruebas en parches.Il est essentiel d'avoir un chronometrage exact et precis entre ordinateurs dans un systeme integre pour les leves hydrographiques afin d'assurer une qualite des donnees appropriee notamment pour les sondeurs multifaisceaux (MBES) qui, dans le cas contraire, peuvent patir de perturbations significatives liees au mouvement. Nous montrons qu'une synchronisation des horloges de l'ordre de 100 a 150ns (valeur quadratique moyenne) est facilement obtenue dans un systeme de leves moderne reposant sur les MBES et utilisant un mecanisme de synchronisation du temps dans un reseau Ethernet et un logiciel specifique de chronometrage. Nous demontrons egalement que l'amelioration du chronometrage permet de supprimer certaines perturbations liees au mouvement dans la bathymetrie observee et de simplifier la procedure d'essai par plage

    High-Precision, High-Accuracy Timekeeping in Distributed Survey Systems

    Get PDF
    Accurate and precise timekeeping between computers in a distributed survey system is essential to ensure adequate data quality, especially with Multibeam Echosounders (MBES) which can otherwise suffer from significant motion artefacts. We show that clock synchronisation on the order of 100-150ns (rms) is readily achievable in a modern MBES-based survey system utilising an Ethernet-based time synchronisation mechanism and some custom timekeeping software. We also show that improving the timekeeping eliminates motion artefacts in the observed bathymetry, and simplifies the patch-test procedure.Para asegurar una calidad adecuada de los datos es esencial una exacta y precisa mantencion de la hora entre ordenadores en un sistema de levantamiento distribuido, especialmente con Sondadores Acusticos Multihaz (MBES), que sino pueden experimentar las consecuencias de un significativo movimiento de sus artefactos. Mostramos que la sincronizaci6n de un reloj en el orden de 100-150ns (rms) puede llevarse a cabo facilmente en un sistema moderno de levantamientos efectuados mediante MBES, utilizando un mecanismo Ethernet basado en la sincronizacion del tiempo y en algun programa de mantencion de la hora adaptado. Tambien mostramos que mejorando la mantencion de la hora se elimina el movimiento de los artefactos en la batimetria observada, y simplifica el procedimiento de pruebas en parches.Il est essentiel d'avoir un chronometrage exact et precis entre ordinateurs dans un systeme integre pour les leves hydrographiques afin d'assurer une qualite des donnees appropriee notamment pour les sondeurs multifaisceaux (MBES) qui, dans le cas contraire, peuvent patir de perturbations significatives liees au mouvement. Nous montrons qu'une synchronisation des horloges de l'ordre de 100 a 150ns (valeur quadratique moyenne) est facilement obtenue dans un systeme de leves moderne reposant sur les MBES et utilisant un mecanisme de synchronisation du temps dans un reseau Ethernet et un logiciel specifique de chronometrage. Nous demontrons egalement que l'amelioration du chronometrage permet de supprimer certaines perturbations liees au mouvement dans la bathymetrie observee et de simplifier la procedure d'essai par plage

    Anti-proliferative but not anti-angiogenic tyrosine kinase inhibitors enrich for cancer stem cells in soft tissue sarcoma.

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    BackgroundIncreasing studies implicate cancer stem cells (CSCs) as the source of resistance and relapse following conventional cytotoxic therapies. Few studies have examined the response of CSCs to targeted therapies, such as tyrosine kinase inhibitors (TKIs). We hypothesized that TKIs would have differential effects on CSC populations depending on their mechanism of action (anti-proliferative vs. anti-angiogenic).MethodsWe exposed human sarcoma cell lines to sorafenib, regorafenib, and pazopanib and assessed cell viability and expression of CSC markers (ALDH, CD24, CD44, and CD133). We evaluated survival and CSC phenotype in mice harboring sarcoma metastases after TKI therapy. We exposed dissociated primary sarcoma tumors to sorafenib, regorafenib, and pazopanib, and we used tissue microarray (TMA) and primary sarcoma samples to evaluate the frequency and intensity of CSC markers after neoadjuvant therapy with sorafenib and pazopanib. Parametric and non-parametric statistical analyses were performed as appropriate.ResultsAfter functionally validating the CSC phenotype of ALDHbright sarcoma cells, we observed that sorafenib and regorafenib were cytotoxic to sarcoma cell lines (P < 0.05), with a corresponding 1.4 - 2.8 fold increase in ALDHbright cells from baseline (P < 0.05). In contrast, we observed negligible effects on viability and CSC sub-populations with pazopanib. At low doses, there was progressive CSC enrichment in vitro after longer term exposure to sorafenib although the anti-proliferative effects were attenuated. In vivo, sorafenib improved median survival by 11 days (P < 0.05), but enriched ALDHbright cells 2.5 - 2.8 fold (P < 0.05). Analysis of primary human sarcoma samples revealed direct cytotoxicity following exposure to sorafenib and regorafenib with a corresponding increase in ALDHbright cells (P < 0.05). Again, negligible effects from pazopanib were observed. TMA analysis of archived specimens from sarcoma patients treated with sorafenib demonstrated significant enrichment for ALDHbright cells in the post-treatment resection specimen (P < 0.05), whereas clinical specimens obtained longitudinally from a patient treated with pazopanib showed no enrichment for ALDHbright cells (P > 0.05).ConclusionsAnti-proliferative TKIs appear to enrich for sarcoma CSCs while anti-angiogenic TKIs do not. The rational selection of targeted therapies for sarcoma patients may benefit from an awareness of the differential impact of TKIs on CSC populations

    Phonemic Cuing: An Investigation of Subject Variables

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    Comparison of potential growth rates of Ceratium hirundinella with observed population density changes

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    Ceratium hirundinella cells in Lake Constance divided during the second half of the night. Growth rates are calculated from the fraction of cells undergoing cell division. Potential growth rates are compared with observed changes in population density. The discrepancy between both is discussed as a possible function of fungal parasitism

    Exploration of crime-scene characteristics in juvenile homicide in the French-speaking part of Belgium

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    This study explores modeling crime-scene characteristics of juvenile homicide in the French-speaking part of Belgium. Multidimensional scaling analysis was carried out on crime-scene characteristics derived from the court files of 67 individuals under 22 years old, who had been charged with murder or attempted murder (1995-2009). Three thematic regions (Expressive: multiple offenders; Instrumental: theft; Instrumental: sex/forensic awareness) distinguished types of aggression displayed during the offense. These themes reaffirm that the expressive-instrumental differentiation found in general homicide studies is valuable when attempting to discriminate juvenile homicides. The proposed framework was found useful to classify the offenses, as 84% of homicides were assigned to a dominant theme. Additionally, associations between crime-scene characteristics and offenders' characteristics were analyzed, but no associations were found, therefore failing to provide empirical support for the homology assumption. Cultural comparisons, as well as the influence of age on the thematic structure are discussed

    Sinking properties of some phytoplankton shapes and the relation of form resistance to morphological diversity of plankton – an experimental study

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    Form resistance (Phi) is a dimensionless number expressing how much slower or faster a particle of any form sinks in a fluid medium than the sphere of equivalent volume. Form resistance factors of PVC models of phytoplankton sinking in glycerin were measured in a large aquarium (0.6 x 0.6 x 0.95 m). For cylindrical forms, a positive relationship was found between Phi and length/ width ratio. Coiling decreased Phi in filamentous forms. Form resistance of Asterionella colonies increased from single cells up to 6-celled colonies than remained nearly constant. For Fragilaria crotonensis chains, no such upper limit to Phi was observed in chains of up to 20 cells ( longer ones were not measured). The effect of symmetry on Phi was tested in 1 - 6-celled Asterionella colonies, having variable angles between the cells, and in Tetrastrum staurogeniaeforme coenobia, having different spine arrangements. In all cases, symmetric forms had considerably higher form resistance than asymmetric ones. However, for Pediastrum coenobia with symmetric/asymmetric fenestration, no difference was observed with respect to symmetry. Increasing number and length of spines on Tetrastrum coenobia substantially increased Phi. For a series of Staurastrum forms, a significant positive correlation was found between arm-length/cell-width ratio and Phi: protuberances increased form resistance. Flagellates (Rhodomonas, Gymnodinium) had a Phi 1. The highest value ( Phi = 8.1) was established for a 20-celled Fragilaria crotonensis chain. Possible origin of the so-called 'vital component' ( a factor that shows how much slower viable populations sink than morphologically similar senescent or dead ones) is discussed, as is the role of form resistance in evolution of high diversity of plankton morphologies
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