BACKGROUND Baroreflex buffering is an important mechanism in arterial blood pressure control. The effect of healthy (physiological) aging on tonic baroreflex buffering in humans is unknown. METHODS AND RESULTS Baroreflex buffering was determined in 27 young (aged 25+/-1 years) and 16 older (aged 65+/-1 years) healthy normotensive men by measuring the potentiation of the systolic blood pressur...

In this paper, we discuss the use of fragmented bandwidth to improve the performance of staggered striping in a multimedia system. It is observed that potential disruptions can occur when nonconsecutive idle disks are used for displaying multimedia objects. We have identified useful retrieval patterns and shown that with proper selections of fragmented disks and a simple buffering scheme, disru...

There is increasing evidence that multimedia traffic in a variety of networks including the Internet, exhibits properties of self-similarity such as long-range dependence and a high-degree of correlation between arrivals. The demands of self-similar traffic impose unique new requirements in switch design, especially as far as the buffering strategy is concerned. In this paper, we study buffer s...

Phillipsite tuff samples from Jebal Aritayn (Jordan) was treated chemically by acid, base, and salt and thermally at 200 and 400 oC. Both treated and untreated phillipsite samples were titrated with HCl and NaOH. The potentiometric titration curves showed that Jordanian phillipsite tuff exists in the base form (pH 8.5) and thus has a remarkable buffering capacity toward H. The effect of chemica...

Epistatic interactions, manifested in the effects of mutations on the phenotypes caused by other mutations, may help uncover the functional organization of complex biological networks1–3. Here, we studied system-level epistatic interactions by computing growth phenotypes of all single and double knockouts of 890 metabolic genes in Saccharomyces cerevisiae, using the framework of flux balance an...

The object identifier index of an object-oriented database system is typically 20% of the size of the database itself, and for large databases, only a small part of the index fits in main memory. To avoid index retrievals becoming a bottleneck, efficient buffering strategies are needed to minimize the number of disk accesses. In this report, we develop analytical cost models which we use to fin...

Reliable multicast delivery requires that a multicast message be received by all members in a group. Hence certain or all members need to buffer messages for possible retransmissions. Designing an efficient buffer management algorithm is challenging in large multicast groups where no member has complete group membership information and the delivery latency to different members could differ by o...

We consider an optimization problem motivated by the tradeoff between connectivity and resilience in key predistribution schemes (KPS) for sensor networks that are based on certain types of combinatorial designs. For a specific class of designs, we show that there is no real disadvantage in requiring the underlying design to be regular.

It is rarely the case that an analyst is presented with a sample in a suitable form for injection into an LC/MS system. Often the sample must be manipulated to concentrate the compound of interest, remove interferences, enzymatically digest the sample to generate surrogate peptides with better mass spectrometric properties, and modify the sample matrix or buffering system to achieve compatibili...