19 research outputs found
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Incremental Evaluation of Ordered Attribute Grammars for Asynchronous Subtree Replacements
Incremental algorithms for evaluating attribute grammars (AGs) have been extensively studied in recent years, primarily because of their application in language-based environments. Ordered attribute grammars are a subclass of AGs for which efficient evaluators can be constructed. Previous incremental algorithms for ordered attribute grammars only allowed one modification to the program at a time, requiring attribute evaluation due to one change to quiesce before another one due to a second change can start. This article presents new incremental evaluation algorithms for ordered attribute grammars that can handle asynchronous program modifications in an optimal manner. Support for asynchronous changes is necessary in environments for multiple users, where different programmers may be making changes to different parts of the program simultaneously. The key to the optimality of the algorithm is an ordering of the attribute evaluations so that an attribute affected by more than one change will only be evaluated once if the changes happen concurrently
Extending Attribute Grammars to Support Programming-in-the-Large
Attribute grammars add specification of static semantic properties to context-free grammars, which in turn describe the syntactic structure of program units. However, context-free grammars cannot express programming-in-the-large features common in modern programming languages, including unordered collections of units, included units and sharing of included units. We present extensions to context-free grammars, and corresponding extensions to attribute grammars, suitable for defining such features. We explain how batch and incremental attribute evaluation algorithms can be adapted to support these extensions, resulting in a uniform approach to intra-unit and inter-unit static semantic analysis and translation of multi-unit programs
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Incremental Attribute Evaluation for Multi-User Semantics-Based Editors
This thesis addresses two fundamental problems associated with performing incremental attribute evaluation in multi-user editors based on the attribute grammar formalism: (1) multiple asynchronous modifications of the attributed derivation tree, and (2) segmentation of the tree into separate modular units. Solutions to these problems make it possible to construct semantics-based editors for use by teams of programmers developing or maintaining large software systems. Multi-user semantics based editors improve software productivity by reducing communication costs and snafus. The objectives of an incremental attribute evaluation algorithm for multiple asynchronous changes are that (a) all attributes of the derivation tree have correct values when evaluation terminates, and (b) the cost of evaluating attributes necessary to reestablish a correctly attributed derivation tree is minimized. We present a family of algorithms that differ in how they balance the tradeoff between algorithm efficiency and expressiveness of the attribute grammar. This is important because multi-user editors seem a practical basis for many areas of computer-supported cooperative work, not just programming. Different application areas may have distinct definitions of efficiency, and may impose different requirements on the expressiveness of the attribute grammar. The characteristics of the application domain can then be used to select the most efficient strategy for each particular editor. To address the second problem, we define an extension of classical attribute grammars that allows the specification of interface consistency checking for programs composed of many modules. Classical attribute grammars can specify the static semantics of monolithic programs or modules, but not inter-module semantics; the latter was done in the past using ad hoc techniques. Extended attribute grammars support programming-in-the-large constructs found in real programming languages, including textual inclusion, multiple kinds of modular units and nested modular units. We discuss attribute evaluation in the context of programming-in-the-large, particularly the separation of concerns between the local evaluator for each modular unit and the global evaluator that propagates attribute flows across module boundaries. The result is a uniform approach to formal specification of both intra-module and inter-module static semantic properties, with the ability to use attribute evaluation algorithms to carry out a complete static semantic analysis of a multi-module program
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Generation of Distributed Programming Environments
This technical report consists of three related papers in the area of distributed programming environments. Incremental Attribute Evaluation in Distributed Language-Based Environments presents algorithms that extend existing technology for the generation of single-user language-based editors from attribute grammars to the cases of multiple-user concurrent and distributed environments. Multi-User Distributed Language-Based Environment, an extended abstract, provides additional information on how to apply the algorithms. Reliability in Distributed Programming Environments presents additional algorithms that extend our results to unreliable networks
Audit on testosterone therapy in adult males with testosterone deficiency
Introduction: Hypogonadism is estimated to affect between 2.1 and 12.8% of the adult male population. Method: A review of 235 patients suffering from hypogonadism was undertaken. Local standards of care were compare to the Endocrine Society Clinical Practice Guideline of 2010 (ESCG). Results: Patients complained of 0, 1-4, 5-8 symptoms suggestive of hypogonadism in 17%, 67% and 16% respectively. 76.5% of the patients had repeatedly low testosterone. 20% suffered from primary hypogonadism. 77% suffered from secondary hypogonadism secondary. Karyotype was obtained in 35% and 5% of the patients suffering from primary and secondary hypogonadism respectively. Patients suffering from secondary hypogonadism had serum TSH (94%), prolactin (92%), cortisol (91%), GH levels (89%) and iron studies (43%) analysed. 77% of patients suffering from secondary hypogonadism had an MRI of the pituitary, with an abnormality reported in 53% of the patients. Prior to starting treatment 7% of the patients were assessed for prostate nodules and PSA was taken in 39% of the patients. Only 33% of the patients had bone mineral density (BMD) taken prior to starting testosterone treatment. Patients were reviewed 3-6 months (35%) and then annually (88%) after treatment was initiated. Conclusion: The study identifies the need for documentation of signs and symptoms. Testosterone levels should be repeated prior to starting treatment. It also highlights the need for karyotyping in patients with primary hypogonadism as well as the need to measure BMD and PSA before and after prescribing testosterone. Patients need review at 3-6months after initiation of testosterone supplementations.peer-reviewe
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MERCURY: Distributed Incremental Attribute Grammar Evaluation
This technical report consists of the two most recent papers from the MERCURY project Multiuser, Distributed Language-Based Environments explains the application of incremental attribute grammar evaluation algorithms to generation of distributed programming environments and describes the implementation of the MERCURY system. Version and Configuration Control in Distributed Language-Based Environments presents new algorithms that permit MERCURY to support multiple versions and configurations of modules and to more efficiently propagate changes to aggregate attributes
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Reliable Network Communications
This technical report consists of three papers from the INTERCOMS project. A Network Architecture for Reliable Distributed Computing introduces the view section model, a network layer for exception handling in response to disruptions in communication channels due to failures of network links or nodes. Remote Exception Handling discusses for a network layer for exception handling among cooperating application processes. Demand-Driven Parameter Passing in Remote Procedure Call describes how remote exception handling solves the problem of passing referential data types (pointers) as parameters to remote procedures
Fludarabine, cytarabine, granulocyte colony-stimulating factor, and idarubicin with gemtuzumab ozogamicin improves event-free survival in younger patients with newly diagnosed aml and overall survival in patients with npm1 and flt3 mutations
Purpose
To determine the optimal induction chemotherapy regimen for younger adults with newly diagnosed AML without known adverse risk cytogenetics.
Patients and Methods
One thousand thirty-three patients were randomly assigned to intensified (fludarabine, cytarabine, granulocyte colony-stimulating factor, and idarubicin [FLAG-Ida]) or standard (daunorubicin and Ara-C [DA]) induction chemotherapy, with one or two doses of gemtuzumab ozogamicin (GO). The primary end point was overall survival (OS).
Results
There was no difference in remission rate after two courses between FLAG-Ida + GO and DA + GO (complete remission [CR] + CR with incomplete hematologic recovery 93% v 91%) or in day 60 mortality (4.3% v 4.6%). There was no difference in OS (66% v 63%; P = .41); however, the risk of relapse was lower with FLAG-Ida + GO (24% v 41%; P < .001) and 3-year event-free survival was higher (57% v 45%; P < .001). In patients with an NPM1 mutation (30%), 3-year OS was significantly higher with FLAG-Ida + GO (82% v 64%; P = .005). NPM1 measurable residual disease (MRD) clearance was also greater, with 88% versus 77% becoming MRD-negative in peripheral blood after cycle 2 (P = .02). Three-year OS was also higher in patients with a FLT3 mutation (64% v 54%; P = .047). Fewer transplants were performed in patients receiving FLAG-Ida + GO (238 v 278; P = .02). There was no difference in outcome according to the number of GO doses, although NPM1 MRD clearance was higher with two doses in the DA arm. Patients with core binding factor AML treated with DA and one dose of GO had a 3-year OS of 96% with no survival benefit from FLAG-Ida + GO.
Conclusion
Overall, FLAG-Ida + GO significantly reduced relapse without improving OS. However, exploratory analyses show that patients with NPM1 and FLT3 mutations had substantial improvements in OS. By contrast, in patients with core binding factor AML, outcomes were excellent with DA + GO with no FLAG-Ida benefit
Incremental Attribute Evaluation with Applications to Multi-User Language-Based Environments
The proposed research addresses three problems associated with performing incremental evaluation of attribute grammars: (1) multiple asynchronous subtree replacements in the parse tree that are initiated by external agents, (2) segmentation of the parse tree according to granularity of access rights with respect to these agents, and (3) distribution of the segments across a reliable network. The research focuses on one exemplary application, distributed multi-user language-based environments, where the parse tree represents a program being developed, the subtree replacements are changes to the program, the external agents are programmers, the granularity of segments corresponds to the modularization of the program, and the nodes of the network are the programmers' workstations
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Extending the MERCURY System to Support Teams of Ada Programmers
We present a model-based vision system that automatically plans the placement and optical settings of vision sensors in order to meet certain generic task requirements common to most industrial machine vision applications. From the planned viewpoints, features of interest on an object will satisfy particular constraints in the image. In this work, the vision sensor is a CCD camera equipped with a programmable lens (i.e. zoom lens) and the image constraints considered are: visibility, resolution and field of view. The proposed approach uses a geometric model of the object as well as a model of the sensor. in order to reason about the task and the environment The sensor planning system then computes the regions in space as well as the optical settings that satisfy each of the constraints separately. These results are finally combined to generate acceptable viewing locations and optical settings satisfying all constraints simultaneously. Camera planning experiments are described in which a robot-arm positions the camera at a computed location and the planned optical settings are set automatically. The corresponding scenes from the candidate viewpoints are shown demonstrating that the constraints are indeed satisfied. Other constraints, such as depth of focus, as well as other vision sensors can also be considered resulting in a fully integrated sensor planning system