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Geriatric assessments have now been recommended as part of the standard evaluation of an older adult considering cancer therapy. While the need for a more in-depth performance status evaluation of an older person with cancer was identified over 20 years ago, completion of a comprehensive geriatric assessment (CGA) is time-consuming and not frequently performed as part of the standard assessment of older cancer patients. Evidence suggests that incorporating such an evaluation could be useful for potentially determining the patient's chemotherapy tolerability or treatment completion, toxicity, and survival, as age alone has been shown to poorly predict treatment failure, and performance status assessments commonly used in oncology practice may lack predictability. This review describes the increasing role of the CGA and geriatric assessment screening tools as well as their pertinent domains across various settings in the evaluation of the older adult with cancer who is considering cancer treatment.

Accumulating evidence shows a critical role of the complement system in facilitating attachment of prions to both B cells and follicular dendritic cells and assisting in prion replication. Complement activation intensifies disease in prion-infected animals, and elimination of complement components inhibits prion accumulation, replication and pathogenesis. Chronic wasting disease (CWD) is a highly infectious prion disease of captive and free-ranging cervid populations that utilizes the complement system for efficient peripheral prion replication and most likely efficient horizontal transmission. Here we show that complete genetic or transient pharmacological depletion of C3 prolongs incubation times and significantly delays splenic accumulation in a CWD transgenic mouse model. Using a semi-quantitative prion amplification scoring system we show that C3 impacts disease progression in the early stages of disease by slowing the rate of prion accumulation and/or replication. The delayed kinetics in prion replication correlate with delayed disease kinetics in mice deficient in C3. Taken together, these data support a critical role of C3 in peripheral CWD prion pathogenesis.

We discuss update scheduling in streaming data warehouses, which combine the features of traditional data warehouses and data stream systems. In our setting, external sources push append-only data streams into the warehouse with a wide range of interarrival times. While traditional data warehouses are typically refreshed during downtimes, streaming warehouses are updated as new data arrive. We model the streaming warehouse update problem as a scheduling problem, where jobs correspond to processes that load new data into tables, and whose objective is to minimize data staleness over time (at time t, if a table has been updated with information up to some earlier time r, its staleness is t minus r). We then propose a scheduling framework that handles the complications encountered by a stream warehouse: view hierarchies and priorities, data consistency, inability to preempt updates, heterogeneity of update jobs caused by different interarrival times and data volumes among different sources, and transient overload. A novel feature of our framework is that scheduling decisions do not depend on properties of update jobs (such as deadlines), but rather on the effect of update jobs on data staleness. Finally, we present a suite of update scheduling algorithms and extensive simulation experiments to map out factors which affect their performance.

Data warehouses collect masses of operational data, allowing analysts to extract information by issuing decision support queries on the otherwise discarded data. In many application areas (e.g. telecommunications), the warehoused data sets are multiple terabytes in size. Parts of these data sets are stored on very large disk arrays, while the remainder is stored on tape-based tertiary storage (which is one to two orders of magnitude less expensive than on-line storage). However, the inherently sequential nature of access to tape-based tertiary storage makes the efficient access to tape-resident data difficult to accomplish through conventional databases.In this paper, we present a way to make access to a massive tape-resident data warehouse easy and efficient. Ad hoc decision support queries usually involve large scale and complex aggregation over the detail data. These queries are difficult to express in SQL, and frequently require self-joins on the detail data (which are prohibitively expensive on the disk-resident data and infeasible to compute on tape-resident data), or unnecessary multiple passes through the detail data. An extension to SQL, the extended multi feature SQL (EMF SQL) expresses complex aggregation computations in a clear manner without using self-joins. The detail data in a data warehouse usually represents a record of past activities, and therefore is temporal. We show that complex queries involving sequences can be easily expressed in EMF SQL. An EMF SQL query can be optimized to minimize the number of passes through the detail data required to evaluate the query, in many cases to only one pass. We describe an efficient query evaluation algorithm along with a query optimization algorithm that minimizes the number of passes through the detail data, and which minimizes the amount of main memory required to evaluate the query. These algorithms are useful not only in the context of tape-resident data warehouses but also in data stream systems which require similar processing techniques.

Traffic, usage, and performance measurements are crucial to the design, operation and control of Internet protocol networks. This article describes a prototype infrastructure for the measurement, storage, and correlation of network data of different types and origins from AT&T's commercial IP network. We focus first on some novel aspects of the measurement infrastructure, then describe analyses that illustrate the power of joining different measured data sets for network planning and design.

Software maintenance is difficult and costly because the maintainer must understand the existing relationships in the maintained code. The maintainer's job can be made considerably easier if the objects in the code (related groups of types, data, and procedures) are identified. In this paper, we discuss methods for identifying objects in programs, and present a new approach that relies on these key features. First, our internal program representation (IPR) lets us make a more precise identification of objects than previous methods allowed. Second, we introduce the idea of receiver-based object identification. Third, we introduce the idea of two-step object identification, which gives the user greater control in precisely identifying objects. Our object finding tool can be used with the other tools our IPR provides to create an integrated software maintenance environment.

Nonblocking algorithms for concurrent objects guarantee that an object is always accessible, in contrast to blocking algorithms in which a slow or halted process can render part or all of the data structure inaccessible to other processes. A number of algorithms have been proposed for shared FIFO queues, but nonblocking implementations are few and either limit the concurrency or provide inefficient solutions. The authors present a simple and efficient nonblocking shared FIFO queue algorithm with O(n) system latency, no additional memory requirements, and enqueuing and dequeuing times independent of the size of the queue. They use the compare & swap operation as the basic synchronization primitive. They model their algorithm analytically and with a simulation, and compare its performance with that of a blocking FIFO queue. They find that the nonblocking queue has better performance if processors are occasionally slow, but worse performance if some processors are always slower than others. >

In many scientific fields, three dimensional surfaces must be reconstructed from a given collection of its surface points. Applications for surface reconstruction exist in medical research and diagnosis as well as in design intensive disciplines. Fuchs, Kedem, and Uselton and Keppel show that surface reconstruction via triangulation can be reduced to the problem of finding a path in a toroidal graph. This paper presents a parallel algorithm to find the minimum cost acceptable path in an m by n toroidal graph. We then show an implementation of the parallel algorithm on a parallel architecture, using a message passing approach. Results are shown, along with suggestions for future enhancements.

This paper examines a previously unanalyzed bistability phenomenon with respect to the number of threads that are doing useful work. This phenomenon is illustrated by a single work queue on a shared-memory machine. An analysis of designs that use two separate memory accesses to lock and unlock critical sections (split transaction) and that employ a first come/first serve queuing mechanism for shared-memory locations is presented. A bistability in the number of threads working, brought about by these conditions, is analyzed and experimentally demonstrated. A simple analysis is presented which predicts the throughput at a critical section of code as a function of the number of applied threads. The study concludes that the mean size of the work items that can be executed in parallel without the possibility of stalling is proportional to the square of the number of threads applied.

Many concurrent B-tree algorithms have been proposed, but their performances have not yet been analyzed satisfactorily. When transaction processing systems require high levels of concurrency, a restrictive serialization technique on the B-tree index can cause a bottleneck. In this paper we present a framework for constructing analytical performance models of concurrent B-tree algorithms. The models can predict the response time and maximum throughput. We analyze a variety of locking algorithms including naive lock-coupling, optimistic descent, two-phase locking, and the Lehman-Yao algorithm. The analyses are validated by simulations of the algorithms on actual B-trees, as well as by simulations done by other researchers