415 research outputs found
SimWorx: An ADA Distributed Simulation Application Framework Supporting HLA and DIS
This research consisted of the analysis, design, and implementation of a reusable application framework for distributed simulation which is compliant with both the DoD High Level Architecture (HLA) for Modeling and Simulation and the Distributed Interactive Simulation (DIS) standards. The goal was to create an Ada-based system for experimentation in distributed simulation. A subsidiary goal was to integrate the system with an existing Air Force Institute of Technology (AFIT) application framework for virtual simulations, Easy_Sim. The application framework was designed using object oriented techniques to enable experimenters to customize it via inheritance extension. The application framework, named SimWorx, consists of two sections: an HLA Federate skeleton, and a surrogate HLA Run Time Infrastructure (RTI) which has an HLA \u27front end and a DIS \u27back end\u27 to provide DIS compatibility. The SimWorx framework was successfully integrated with Easy_Sim to provide an Ada based joint simulation system for distributed virtual simulations
Se découvrir en se racontant
Ce travail de recherche consiste à analyser ce que produit la participation d’un groupe d’adolescents, vivant des difficultés personnelles, familiales, scolaires et sociales, à un atelier de création basé sur le récit de vie dans lequel la question du « Qui suis-je ? » est prédominante. L’objectif de ce Travail de Bachelor est de comprendre comment les adolescents en question se définissent afin d’avoir des pistes d’intervention en fonction de leurs représentations d’eux-mêmes
STM Studies of Synthetic Peptide Monolayers
We have used scanning probe microscopy to investigate self-assembled
monolayers of chemically synthesized peptides. We find that the peptides form a
dense uniform monolayer, above which is found a sparse additional layer. Using
scanning tunneling microscopy, submolecular resolution can be obtained,
revealing the alpha helices which constitute the peptide. The nature of the
images is not significantly affected by the incorporation of redox cofactors
(hemes) in the peptides.Comment: 4 pages, 3 figures (4 gifs); to appear in the Proceedings of the
XIIth Int. Winterschool on Electronic Properties of Novel Materials
"Molecular Nanostructures", Kirchberg/Tyrol, Febr. 199
Perceptions of Race and Ancestry in Teaching, Research, and Public Engagement in Biological Anthropology
The concept of race has a complex history in the field of biological anthropology. Despite increased recognition of the racist origins of the discipline, there remains little agreement about what the concept means, how it is used, or how it is discussed. The present study presents the results of a survey of biological anthropologists to investigate the relationship of biological anthropology/ists with race and ancestry. The survey focuses on the areas of research, public engagement, and teaching as related to these concepts. Results indicate that a large majority of biological anthropologists argue for the separation of race (as a social not biological concept) from ancestry. The majority of respondents argued that ancestry categories should be based on geography (e.g., Asian, European, and African), and more anthropologists thought the terms “Hispanic/Latino” were inappropriate ancestry categories. While the majority of respondents felt that discussions of these terms were not matters of “political correctness,” nearly a quarter of respondents suggested that concerns over the moral and ethical implications of research (e.g., photos, terminology, ancestry, etc.) result in the silencing of anthropological research. Overwhelmingly, respondents felt that anthropologists have a responsibility to ensure the avoidance of misappropriation of their work in race science and by white nationalists/supremacists. Some differences in survey responses were found among respondents in relation to sub-discipline, educational level, location of respondents, age, self-identified racial/ethnic categories, and gender. In regard to teaching, survey results indicate that these concepts are minimally covered in university classrooms. When taught, topics focused on the colonialist/racist history of anthropology, the presence of white privilege/supremacy, and racism. Based on the results of this survey, we argue for greater public engagement on these concepts, a standardized system of teaching race and ancestry, and a disciplinary conversation about practice and terminology. In this way, biological anthropologists can best place themselves to combat racism in a socially responsible way
Structures de déformation alpines dans le synclinal de Permo-Carbonifère de Salvan-Dorénaz (massif des Aiguilles Rouges, Valais)
A new structural interpretation of the Salvan-Dorénaz syncline (Aiguilles Rouges massif) is proposed; it proves that this syndine, filled with Permo-Carboniferous sediments, is mainly an alpine structure. The geologic evolution comprises the following stages :
a) Stephanian A - unknown date (Upper Stephanian, Autunian (?)): continental detrital sediments fill a NNE-SSW intramountainous trough in subsidence. Red layers define long alluvial fans imbricated in a dark sequence of sandstones and mudstones, with coals and lacustrine limestones.
b) Weak deformations occur during the «Saalic» tectonic phase (Permian). They correspond to the readjustment of relatively "plastic" sedimentary layers to brittle deformations that affect the underlying pre-Stephanian basement.
The progressive cessation of these movements during late Permian is followed by a "peneplanation" stage. The Permo-Carboniferous beds are eut by the transgressive Triassic deposits along a low-angle unconformity.
c) Alpine deformations start during Upper Eocene times; a first phase records the formation of the "parautochtonous slices" and the emplacement of the Morcles nappe (large recumbent fold). The separation of the "parautochtonous slices" is probably connected with early deformations of the basement-cover contact.
d) During a second phase, the pre-Triassic basement of the Aiguilles Rouges massif is affected by deformation (large-scale folding) and the more ductile Permo-Carboniferous sediments are strongly folded (formation of the Salvan-Dorénaz syncline).
For two reasons, (a) the continuation of the translation towards the NW of the Morcles nappe, (b) the disharmonie folds that appear in the Triassic rocks of the autochtonous cover, the folding of the Permo-Carboniferous only affects moderately the basal thrust of the Morcles nappe.
The metamorphic grade reaches the anchizone-epizone limit
Scientific Integrity in the Forensic Sciences: Consumerism, Conflicts of Interest, and Transparency
The goal of this paper is to discuss scientific integrity, consumerism, conflicts of interest, and transparency within the context of forensic science. Forensic scientists play crucial roles within the legal system and are constantly under various pressures when performing analytical work, generating reports based on their analyses, or testifying to the content of these reports. Maintaining the scientific integrity of these actions is paramount to supporting a functional legal system and the practice of good science. Our goal is to discuss the importance of scientific integrity as well as the factors it may compromise, so that forensic practitioners may be better equipped to recognize and avoid conflicts of interest when they arise. In this discussion we define terms, concepts, and professional relationships as well as present three case studies to contextualize these ideas
A comparison of in vivo 13C MR brain glycogen quantification at 9.4 and 14.1 T.
The high molecular weight and low concentration of brain glycogen render its noninvasive quantification challenging. Therefore, the precision increase of the quantification by localized (13) C MR at 9.4 to 14.1 T was investigated. Signal-to-noise ratio increased by 66%, slightly offset by a T(1) increase of 332 ± 15 to 521 ± 34 ms. Isotopic enrichment after long-term (13) C administration was comparable (≈ 40%) as was the nominal linewidth of glycogen C1 (≈ 50 Hz). Among the factors that contributed to the 66% observed increase in signal-to-noise ratio, the T(1) relaxation time impacted the effective signal-to-noise ratio by only 10% at a repetition time = 1 s. The signal-to-noise ratio increase together with the larger spectral dispersion at 14.1 T resulted in a better defined baseline, which allowed for more accurate fitting. Quantified glycogen concentrations were 5.8 ± 0.9 mM at 9.4 T and 6.0 ± 0.4 mM at 14.1 T; the decreased standard deviation demonstrates the compounded effect of increased magnetization and improved baseline on the precision of glycogen quantification
Extended endoscopic mucosal resection in the esophagus and hypopharynx: a new rigid device
We present a new device allowing for the diagnosis and treatment of extended superficial lesions of the esophagus and hypopharynx such as early squamous cell carcinoma, intestinal metaplasia with high grade intraepithelial neoplasia or early adenocarcinoma arising in Barrett's esophagus. A new modified rigid esophagoscope (Karl Storz GmbH, Germany) has been designed. A large mucosal area is sucked against a transparent and perforated hemi-cylindrical window. Mucosal resection is performed by an electrical wire loop at a constant depth of 1±0.1mm. The resected surface varies from 4 to 12cm2. Circumferential resection consists of two opposite individual hemi-circumferential resections. We performed three series of animal trials: hemicircumferential mucosectomies; circumferential resections of variable (2 to 6cm) length and long-segment mucosectomies with follow-up. Hemi- and circumferential resections could be done in one or two specimens only which allowed precise histological studies. This facilitated easy orientation and analysis of the surgical margins. The deep resection margin was precisely located at the submucosal level, a prerequisite for a safe resection of superficial cancers of the esophagus and hypopharyn
Fluorine-19 magnetic resonance angiography of the mouse.
PURPOSE: To implement and characterize a fluorine-19 ((19)F) magnetic resonance imaging (MRI) technique and to test the hypothesis that the (19)F MRI signal in steady state after intravenous injection of a perfluoro-15-crown-5 ether (PCE) emulsion may be exploited for angiography in a pre-clinical in vivo animal study.
MATERIALS AND METHODS: In vitro at 9.4T, the detection limit of the PCE emulsion at a scan time of 10 min/slice was determined, after which the T(1) and T(2) of PCE in venous blood were measured. Permission from the local animal use committee was obtained for all animal experiments. 12 µl/g of PCE emulsion was intravenously injected in 11 mice. Gradient echo (1)H and (19)F images were obtained at identical anatomical levels. Signal-to-noise (SNR) and contrast-to-noise (CNR) ratios were determined for 33 vessels in both the (19)F and (1)H images, which was followed by vessel tracking to determine the vessel conspicuity for both modalities.
RESULTS: In vitro, the detection limit was ∼400 µM, while the (19)F T(1) and T(2) were 1350±40 and 25±2 ms. The (19)F MR angiograms selectively visualized the vasculature (and the liver parenchyma over time) while precisely coregistering with the (1)H images. Due to the lower SNR of (19)F compared to (1)H (17±8 vs. 83±49, p<0.001), the (19)F CNR was also lower at 15±8 vs. 52±35 (p<0.001). Vessel tracking demonstrated a significantly higher vessel sharpness in the (19)F images (66±11 vs. 56±12, p = 0.002).
CONCLUSION: (19)F magnetic resonance angiography of intravenously administered perfluorocarbon emulsions is feasible for a selective and exclusive visualization of the vasculature in vivo
- …