Overhydration measured by bioimpedance analysis and the survival of patients on maintenance hemodialysis: a single-center study

AbstractBackgroundBioimpedance analysis (BIA) helps measuring the constituents of the body noninvasively. Prior studies suggest that BIA-guided fluid assessment helps to predict survival in dialysis patients. We aimed to evaluate the clinical usefulness of BIA for predicting the survival rate of hemodialysis patients in Korea.MethodsWe conducted a single-center retrospective study. All patients were diagnosed with end-stage renal disorder and started maintenance hemodialysis between June 2009 and April 2014. BIA was performed within the 1st week from the start of hemodialysis. The patients were classified into 2 groups based on volume status measured by the body composition monitor (BCM; Fresenius): an overhydrated group [OG; overhydration/extracellular water (OH/ECW) >15%] and a nonoverhydrated group (NOG; OH/ECW ≤15%).ResultsA total of 344 patients met the inclusion criteria. Of these, 252 patients (73.3%) were categorized into the OG and 92 patients (26.7%) into the NOG. Age- and sex-matching patients were selected with a rate of 2:1. Finally, 160 overhydrated patients and 80 nonoverhydrated patients were analyzed. Initial levels of hemoglobin and serum albumin were significantly lower in the OG. During follow-up, 43 patients from the OG and 7 patients from the NOG died (median follow-up duration, 24.0 months). The multivariate-adjusted all-cause mortality was significantly increased in the OG (odds ratio, 2.569; P = 0.033) and older patients (odds ratio, 1.072/y; P < 0.001). No significant difference of all-cause or disease-specific admission rate was observed between the 2 groups.ConclusionThe ratio of OH/ECW volume measured with body composition monitor is related to the overall survival of end-stage renal disorder patients who started maintenance hemodialysis

Extended Synchronous Dataflow for Efficient DSP System Prototyping

Though synchronous dataflow (SDF) graph has been a successful input specification language for digital signal processing (DSP) applications, lack of support for global states makes it unsuitable for multimedia signal processing applications that need global states for efficient implementation. In this paper, we propose synchronous piggybacked dataflow (SPDF), an extension of SDF model to accommodate global states without side effects. Global states are accessed by a special block that piggybacks the global state update request on data samples. Such an extension enlarges the domain of application where dataflow representation can be used for rapid system prototyping. The only penalty it incurs is scheduling complexity since the scheduler now considers control dependency as well as data dependency. We present the static analysis of the SPDF model and an implementation technique for memory efficient code synthesis. Finally, we show experimental results with a real life example, MPEG-audio decoder, to present the novelty and usefulness of our approach.This research was supported in part by the Korean Ministry of Information and Communication(MIC) under the program of University Research, the Brain Korea 21 Project, and the National Research Laboratory(NRL) grant. The RIACT at Seoul National University provides research facilities for this study

Fast memory snapshot for concurrent programming without synchronization

The industry-wide turn toward chip-multiprocessors (CMPs) provides an increasing amount of parallel resources for commodity systems. However, it is still difficult to harness the available parallelism in user applications and system software code. We propose MShot, a hardware-assisted memory snapshot for concurrent programming without synchronization code. It supports atomic multi-word read operations on a large dataset. Since modern processors support atomic access only to a single word, programmers should add synchronization code to process a multiword dataset concurrently in multithreading environment. With snapshot, programmers read the dataset atomically and process the snapshot image without synchronization code. We implement MShot using hardware resources for transactional memory and reduce the storage overhead from 2.98% to 0.07%. To demonstrate the usefulness of fast snapshot, we use MShot to implement concurrent versions of garbage collection and call-path profiling. Without the need for synchronization code, MShot allows such system services to run in parallel with user applications on spare cores in CMP systems. As a result, the overhead of these services is minimized, approaching that of an ideal implementation. Copyright 2009 ACM

Efficient Dataflow Representation Of Mpeg-1 Audio (Layer III) . . .

We present an efficient dataflow representation of MPEG-1 Audio (Layer III) Decoder (MP3) algorithm with controlled global states. Although dataflow graph has been a successful representation language for DSP applications, lack of global states makes it unsuitable to some applications that require periodic parameter update and dynamic behavior of function blocks. We show the global states can solve these problems and be fused into dataflow graph without any side effect. With a reallife example such as MP3 decoder, we present the novelty and usefulness of our approach

Efficient Dataflow Representation of MPEG-1 Audio (Layer III) Decoder Algorithm with Controlled Global States

We present an efficient dataflow representation of MPEG-1 Audio (Layer III) Decoder (MP3) algorithm with controlled global states. Although dataflow graph has been a successful representation language for DSP applications, lack of global states makes it unsuitable to some applications that require periodic parameter update and dynamic behavior of function blocks. We show the global states can solve these problems and be fused into dataflow graph without any side effect. With a reallife example such as MP3 decoder, we present the novelty and usefulness of our approach. INTRODUCTION Dataflow graph has been a successful representation for DSP algorithms since dataflow semantics is well matched with algorithmic function flow in DSP applications [1][2]. In a dataflow graph, a node represents a function block such as an FIR filter or a Gain, and an arc between nodes represents the flow dependency as shown in figure 1. A function block may contain states inside, called local states or param..

Extended Synchronous Dataflow for Efficient DSP System Prototyping

Though dataflow graph has been a successful input specification language for DSP system prototyping, lack of support for global states makes it unsuitable to some important applications that need global states for efficient implementation. In this paper, we propose an extension of synchronous dataflow graph to accommodate global states without side effects. Global states are accessed by a special block that piggybacks the state update request on data samples. Such an extension enlarges the domain of application where dataflow representation can be used for rapid system prototyping. Only penalty it incurs is scheduling complexity since the scheduler now considers the control dependency as well as data dependency. We show experimental results with real-life examples such as MPEG-audio decoder and 3D graphics pipeline to present the novelty and usefulness of our approach. 1 Introduction Dataflow graph (DFG) has been a successful representation for DSP algorithms since dataflow semantics ..