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The ventilatory response to carbon dioxide (CO2) measured by modified rebreathing (SrVE) is closer to that measured by the steady-state method (SsVE) than is the response measured by Read's rebreathing method. Furthermore, the value estimated by the steady-state method depends upon the number of data points used to measure it. We planned to assess if these observations were also true for cerebral blood flow (CBF), as measured by steady-state (SsCBF) and modified rebreathing (SrCBF) tests. Six subjects undertook two protocols, one in the steadystate and one with modified rebreathing. SsVE depended upon the number of data points used to calculate it, and SsVE and SrVE were similar. However, this was not the case with SsCBF, and SsCBF was much higher than SrCBF. These findings are consistent with the notions that the specific CO2 stimulus differs for CBF control as compared with ventilation (VE) control, and that prior hypocapnia has an effect on CBF and VE for longer than the duration of the hypocapnia. [ABSTRACT FROM AUTHOR]

This study was a systematic review of the anesthetic effect on carotid body response to hypoxia. We undertook a systematic literature search (electronic plus manual) for full-paper articles in English that used methodologies enabling any anesthetic effect to be located to the carotid body. We found just 7 articles that met our inclusion criteria, incorporating 16 separate studies. Anesthetic (mean dose ± SD 0.70 ± 0.33 MAC) significantly depressed carotid body response by 24% (p = 0.041). There were no differences between individual agents (halothane, enflurane, isoflurane) and no influence of the use of neuromuscular blockade or of species (although the data were sufficiently sparse to interpret such sub-group analysis with caution). [ABSTRACT FROM AUTHOR]

Computer modeling can provide insights into the existence, structure, size, and thermodynamic stability of localized raft-like regions in membranes. However, the challenges in the construction and simulation of accurate models of heterogeneous membranes are great. The primary obstacle in modeling the lateral organization within a membrane is the relatively slow lateral diffusion rate for lipid molecules. Microsecond or longer time-scales are needed to fully model the formation and stability of a raft in a membra ne. Atomistic simulations currently are not able to reach this scale, but they do provide quantitative information on the intermolecular forces and correlations that are involved in lateral organization. In this chapter, the steps needed to carry out and analyze atomistic simulations of hydrated lipid bilayers having heterogeneous composition are outlined. It is then shown how the data from a molecular dynamics simulation can be used to construct a coarse-grained model for the heterogeneous bilayer that can predict the lateral organization and stability of rafts at up to millisecond time-scales. [ABSTRACT FROM AUTHOR]

In this article, we consider energy-efficient implementation of the SQL join operation in sensor databases, when the join selection condition is a range predicate. Apart from two simple approaches, we propose distributed hash-join and index-join algorithms for implementation of range-join operations in sensor networks. Through extensive simulations, we show that hash-join as well as index-join approaches significantly outperform the simple approaches, even for moderately sized networks. Our experiments also reveal that although both approach scale well, the index-join algorithm performs better than the hash-join algorithm especially in large sensor networks. [ABSTRACT FROM AUTHOR]

Recently, applications in which relational data is generated in a distributed and streaming manner have emerged from diverse domains. Processing queries on such data has become very important. In-network evaluation of a query is a technique in which the query is evaluated in the network without transferring all the data to a central location. So far, algorithms for in-network of evaluation of a single query have been proposed. They are not designed to exploit common computations across multiple queries. There is a need to develop techniques for efficient in-network evaluation of multiple queries. We consider the problem of in-network evaluation of multiple queries on relational data generated on a distributed network of machines. We present a novel algorithm based on an algorithm for dynamic regrouping of queries. [ABSTRACT FROM AUTHOR]

We discuss the implementation of Ψ-analysis for the structural characterization of protein folding transition states. In Ψ-analysis, engineered bi-histidine metal ion binding sites are introduced at surface positions to stabilize secondary and tertiary structures. The addition of metal ions stabilizes the interaction between the two known histidines in a continuous fashion. Measuring the ratio of transition state stabilization to that of the native state provides information about the presence of the metal binding site in the transition state. Ψ-Analysis uses noninvasive surface mutations and does not require specialized equipment, so it can be readily applied to characterize the folding of many proteins. As a result, this method can provide a wealth of high-resolution quantitative data for comparison with theoretical folding simulations. Additionally, investigations of other biological processes also may utilize metal binding sites and Ψ-analysis to detect conformational events during catalysis, assembly, and function. [ABSTRACT FROM AUTHOR]

We consider the online scheduling problem for sorting buffers on a line metric, motivated by an application to disc scheduling. Input is an online sequence of requests. Each request is a block of data to be written on a specified track of the disc. To write a block on a particular track, the scheduler has to bring the disc head to that track. The cost of moving the disc head from a track to another is the distance between those tracks. A sorting buffer that can store at most k requests at a time is available to the scheduler. This buffer can be used to rearrange the input sequence. The objective is to minimize the total cost of head movement while serving the requests. On a disc with n uniformly-spaced tracks, we give a randomized online algorithm with a competitive ratio of O(log2n) in expectation against an oblivious adversary. We show that any deterministic strategy which makes scheduling decisions based only on the contents of the buffer has a competitive ratio of Ω(k) or Ω(log n/loglog n). [ABSTRACT FROM AUTHOR]

In this paper, we define a network service provider game. We show that the price of anarchy of the defined game can be bounded by analyzing a local search heuristic for a related facility location problem called the k-facility location problem. As a result, we show that the k-facility location problem has a locality gap of 5. This result is of interest on its own. Our result gives evidence to the belief that the price of anarchy of certain games are related to analysis of local search heuristics. [ABSTRACT FROM AUTHOR]

Key challenges in the area of Intrusion Detection are the reduction of false alarms, event correlation & attack prediction. As a part of DIT, MCIT, Govt. of India supported project to carry out research and development in the area of Intrusion Detection System (IDS), we have developed N@G (Network at Guard). While developing N@G, we faced various challenges pertaining to performance, accuracy, analysis, survivability, adaptability and standards. In this paper we discuss these challenges and share our experiences, bringing out our approach towards solving them. Keywords: Challenges in IDS, IDS Architecture, IDS Standards. [ABSTRACT FROM AUTHOR]

Active image processing is an attempt to overcome some limitations of the classical, intuition based approach for developing image processing solutions. It's goals are to allow for intuitive specification of image processing tasks and to take advantage of the ability to influence the scene. The general structure is that of interconnected, self-configuring stages. To formalize communication between these stages conceptual graphs have been found useful to serve for both, as a representation for the scene model as well as for the stage configuration. [ABSTRACT FROM AUTHOR]