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The Cygnus Dual Beam Radiographic Facility consists of two identical radiographic sources with the following specifications: 4-rad dose at 1 m, 1-mm spot size, 50-ns pulse length, 2.25-MeV endpoint energy. The facility is located ...
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The Cygnus Dual Beam Radiographic Facility consists of two identical radiographic sources with the following specifications: 4-rad dose at 1 m, 1-mm spot size, 50-ns pulse length, 2.25-MeV endpoint energy. The facility is located in an underground tunnel complex at the Nevada Test Site. Here SubCritical Experiments (SCEs) are performed to study the dynamic properties of plutonium. The Cygnus sources were developed as a primary diagnostic for these tests. Since SCEs are single-shot, high-value events - reliability and reproducibility are key issues. Enhanced reliability involves minimization of failure modes through design, inspection, and testing. Many unique hardware and operational features were incorporated into Cygnus to insure reliability. Enhanced reproducibility involves normalization of shot-to-shot output also through design, inspection, and testing. The first SCE to utilize Cygnus, Armando, was executed on May 25, 2004. A year later, April - May 2005, calibrations using a plutonium step wedge were performed.
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Definitions of virus species based on biological (gene pools), ecological(niches), evolutionary (lineages), or phenetic (morphology) criteria were considered and rejected. The concept of the polythetic species, on the other hand, ...
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Definitions of virus species based on biological (gene pools), ecological(niches), evolutionary (lineages), or phenetic (morphology) criteria were considered and rejected. The concept of the polythetic species, on the other hand, found general favor since it can accommodate the inherent variability of viruses and it does not depend on the existence of a unique diagnostic feature. A polythetic class is distinguished from an ordinary class in that the members of the former need not have any single property in common. Each member of a polythetic class is defined by more than one property, and no single property is necessary or sufficient for membership of a polythetic class.
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These guidelines for the treatment of patients who have sexually transmitted diseases (STDs) were developed by the Centers for Disease Control and Prevention (CDC) after consultation with a group of professionals knowledgeable in ...
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These guidelines for the treatment of patients who have sexually transmitted diseases (STDs) were developed by the Centers for Disease Control and Prevention (CDC) after consultation with a group of professionals knowledgeable in the field of STDs who met in Atlanta on September 2628, 2000. The information in this report updates the 1998 Guidelines for Treatment of Sexually Transmitted Diseases (MMWR 1998;47(No. RR-1)). Included in these updated guidelines are new alternative regimens for scabies, bacterial vaginosis, early syphilis, and granuloma inguinale; an expanded section on the diagnosis of genital herpes (including type-specific serologic tests); new recommendations for treatment of recurrent genital herpes among persons infected with human immunodeficiency virus (HIV); a revised approach to the management of victims of sexual assault; expanded regimens for the treatment of urethral meatal warts; and inclusion of hepatitis C as a sexually transmitted infection. In addition, these guidelines emphasize education and counseling for persons infected with human papillomavirus, clarify the diagnostic evaluation of congenital syphilis, and present information regarding the emergence of quinolone-resistant Neisseria gonorrhoeae and implications for treatment. Recommendations also are provided for vaccine-preventable STDs, including hepatitis A and hepatitis B.
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During the past decade, Cryptosporidium has become acknowledged as an importanthuman pathogen. Although the first two human cases were only described in 1976 with a half dozen more reported during the next six years, the onset of ...
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During the past decade, Cryptosporidium has become acknowledged as an importanthuman pathogen. Although the first two human cases were only described in 1976 with a half dozen more reported during the next six years, the onset of the acquired immunodeficiency syndrome (AIDS) pandemic led to recognition of Cryptosporidium as an agent of fulminant and potentially life-threatening diarrhea (1-6). Now, there are over 300 scientific publications on human cryptosporidiosis many of which focus on areas of current research: refining diagnostic techniques, understanding pathogenesis and evaluating promising therapies.
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This report summarizes the papers published in various journals and technical reports supported by the project (stated above) undertaken by the Office of Naval Research.
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Comparative analysis is the problem of predicting how a system will react to perturbations in its parameters, and why. For example, comparative analysis could be asked to explain why the period of an oscillating spring/block syste...
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Comparative analysis is the problem of predicting how a system will react to perturbations in its parameters, and why. For example, comparative analysis could be asked to explain why the period of an oscillating spring/block system would increase if the mass of the block were larger. This thesis formalizes the task of comparative analysis and presents two solution techniques: differential qualitative (DQ) analysis and exaggeration. Both techniques solve many comparative analysis problems, providing explanations suitable for use by design systems, automated diagnosis, intelligent tutoring systems, and explanation based generalization. This thesis explains the theoretical basis for each technique, describes how they are implemented, and discusses the difference between the two. Although exaggeration does occasionally produce misleading answers, it solves a larger class of problems than DQ analysis and frequently results in simpler explanations. (kr)
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My long-term goal is to contribute to the advancement of the observations, structural analysis, dynamical diagnosis, and numerical prediction of the life cycles of synoptic-scale and mesoscale weather systems. This includes the in...
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My long-term goal is to contribute to the advancement of the observations, structural analysis, dynamical diagnosis, and numerical prediction of the life cycles of synoptic-scale and mesoscale weather systems. This includes the influence of planetary-scale, inter-annual and intra-seasonal variability on their evolution. These weather systems include: mid-latitude and arctic oceanic and land-falling cyclones, fronts and their associated cloud, wind, and precipitation systems; upper-level jet streams and clear-air turbulence, extreme topographic flows and their interactions with the ocean.
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How do we know how many opinions are required to make a diagnosis with necessary accuracy. One way is by examining how often physicians agree on the diagnosis. This Note discusses statistical techniques that can be used to analyze...
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How do we know how many opinions are required to make a diagnosis with necessary accuracy. One way is by examining how often physicians agree on the diagnosis. This Note discusses statistical techniques that can be used to analyze agreement data to address this and related questions. Specifically, these methods make it possible to determine from the opinions of panels of diagnosticians in an agreement study the following: (1) the probable accuracy of an individual diagnosis; (2) the probability of disease presence or absence given unanimous or conflicting opinions by several diagnosticians; and (3) how many opinions should be required to make the diagnosis. The methods discussed include two related techniques, which differ in assumptions about disease subtypes and associated differences among cases in their ability to be correctly diagnosed. These techniques have many applications in addition to that of medical diagnosis.
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Understanding group and intergroup relations in living human systems takes three orders of conceptual framework. The first pertains to those aspects of groups that share properties with all living systems. The second deals with pr...
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Understanding group and intergroup relations in living human systems takes three orders of conceptual framework. The first pertains to those aspects of groups that share properties with all living systems. The second deals with properties of three levels of human systems--individuals, groups, and organizations. And the third uses concepts uniquely suited to the phenomena of group and intergroup relations in organizations. The concept of parallel processes explains interdependence of phenomena at the different levels of analysis and provides a means to relate dynamic processes in human systems and in the diagnostic process itself. As presented in chapter one, the philosophy of clinical social science dictates that investigators examine themselves as well as the phenomena they study. Therefore the concepts presented here are intended for use not only by investigators to understand groups and social systems but also to observe and change themselves, if appropriate, as they conduct research. The theory applies to the researched and to the researcher.
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This report presents different approaches to data based organizational diagnosis (in particular, distance function, discriminant function, decision tree, and a Bayesian approach) and their effectiveness when applied to approximate...
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This report presents different approaches to data based organizational diagnosis (in particular, distance function, discriminant function, decision tree, and a Bayesian approach) and their effectiveness when applied to approximately 6,000 work groups. In particular, several different criteria are used to evaluate the classification techniques: proportion of correct classification, ability to reproduce the typology, a zero-one closeness measure, severity of misclassification, the information required to make classifications, the amount of data required to develop the procedure, and the ease of implementing the procedure. Discussion of these issues, and, as a consequence, suggestions for further investigation are included. (Author)
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