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1.
Amar A. DESAI Allen NISSENSON Glenn M. CHERTOW Mary FARID Inder SINGH Martijn G. H. VAN OIJEN Eric ESRAILIAN Matthew D. SOLOMON Brennan M. R. SPIEGEL 《Hemodialysis international. International Symposium on Home Hemodialysis》2009,13(3):347-359
Despite data that traditional laboratory-based outcome measures in dialysis are improving over time, population-based data indicate that mortality rates are not improving in parallel. With increased focus on performance measures based on laboratory-based outcomes (e.g., hematocrit, albumin, and parathyroid hormone), less emphasis has been placed on other markers, some of which may be stronger predictors of mortality. We performed a systematic review to interpret the predictive value of laboratory-based outcome measures in dialysis. We identified studies with data regarding the predictive value of laboratory-based outcomes for mortality in dialysis. We calculated the sample size-weighted pooled relative risk of death with dichotomized "high" vs. "low" levels of each measure. We rank-ordered predictors by scaling the pooled relative risk of each measure by its pooled standard deviation. There were 5171 titles, of which 128 (representing 44 laboratory-based outcomes) were selected. Nine were significantly associated with mortality, in order of decreasing scaled effect size: (1) tumor necrosis factor-α, (2) hematocrit, (3) interleukin-6, (4) troponin T, (5) Kt/Vurea , (6) prealbumin, (7) urea reduction ratio, (8) serum albumin, and (9) C-reactive protein. Other oft-cited measures such as calcium phosphate product and parathyroid hormone were not significantly associated with mortality in pooled analysis. Quality improvement efforts to improve traditional laboratory-based outcomes in end-stage renal disease are necessary, but likely insufficient, to improve overall mortality in dialysis. Renewed consideration of cardiovascular, inflammatory, and nutritional markers that are especially strong predictors of mortality may have important implications for risk stratification and targeted therapeutic interventions. 相似文献
2.
The idea of information improvement was introduced by Thiel [3]. This idea was further extended by the first author to information improvement due to 2 and N revisions and specifically states that different experimenters (a finite number) are required to proceed with given distributions P and U and are permitted to choose a suitable revision. We attempted to provide a measure of information corresponding to Theil's measure which reflected the effect of all revisions. In this paper, the authors have studied a joint characterization of information improvement of N revisions and its generalization by considering a suitable functional equation. 相似文献
3.
High levels of reliability can be predicted and achieved as far as the hardware portions of modern large and complex real-time computer-based control systems are concerned but software is a critical part and plays a vital role in influencing the overall system reliability. This paper presents a comparative study between hardware reliability and software reliability from three definitions: top level, intermediate level and low level based on user's point of view, system designer's point of view and quantitative measurement point of view, respectively. Also discussed is the hardware reliability theory vs software reliability theory on the basis of analysis of malfunctions and prevailing reliability trends. 相似文献
4.
5.
Concentrations of native and gold defects in HgCdTe from first principles calculations 总被引:1,自引:0,他引:1
We have studied the defect formation energies of the various native (vacancies, interstitials, and antisites) and Au defects
in Hg1−xCdxTe using density functional-based total energy calculations with ultrasoft pseudo-potentials. These studies are important
for infrared (IR) detection technology where the device performance can be severely degraded because of defects. To calculate
formation energies, we modeled the neutral and charged defects using supercells containing 64 atoms. From the formation energies,
we have determined the defect concentrations as a function of stoichiometry and temperature. We find the prevalent neutral
defects to be Au at the Hg site (AuHg
), Hg vacancies (VHg
), and Te antisites (TeHg
). We have also explicitly studied charged defects and have found Te
Hg
2+
, Au
Hg
1−
, V
Hg
1−
, V
Hg
2−
, and V
Te
2+
to have low formation energies. We have identified AuHg
to be the prevalent Au defect, having concentrations several orders of magnitude greater than the other Au defects. We find
that the charge state of VHg is primarily (1−) or (2−) depending on the electronic chemical potential. 相似文献
6.
7.
Inder M. Soi 《Microelectronics Reliability》1985,25(2):229-233
One of the main advantages of distributed databases is their inherent reliability but also associated are problems that must be overcome before it can be achieved. In this paper, we attempt to discuss major design alternatives faced by the designer of a reliable fully replicated distributed database. 相似文献
8.
Factors influencing the use of infant car restraints 总被引:1,自引:0,他引:1
Over a six-week period 100 mothers in Dunedin, New Zealand obtained General Motors infant car seats from a rental scheme. In interviews conducted in the maternity hospital, before the seats had been used, the mother's perceptions of the comfort and ease of use of the seat were recorded. All mothers rated the seats as very safe. From details of 2,830 car trips undertaken by these mothers while their infants were 0-3 months old and from a further 687 journeys by 85 of those mothers when their infants were 4-6 months old we found that an infant car seat was used for only 72% of journeys with the younger infant compared to 91% of journeys with the older infant. Those mothers who had rated the seat--before ever using it--as appearing uncomfortable or difficult to use were less likely to make use of it. The seat was least likely to be used when the mother was going out for more than two hours in the evening for some purpose that involved only a short car journey. 相似文献
9.
Inder Jeet Taneja 《Information Sciences》1979,18(3):223-233
The idea of information improvement was introduced by Theil in 1967. This idea is further extended in this paper to information improvement due to 2 and N revisions. These measures are characterized by a generalized functional equation. Some related properties of information improvement due to N revisions are also mentioned. 相似文献
10.
The various mechanisms by which radium can be retained by uranium mill tailings are discussed. These include coprecipitation (solid solutions), adsorption on silica and hydroxides, ion exchange in clay minerals, and retention in pores. Previous work on radium removal from mill tailings and on radioactive disequilibrium in uranium deposits is critically reviewed in relation to these mechanisms. Fresh data are presented, indicating the roles of charge-depressant ions and of organic complexing agents in radium removal. The addition of reducing agent has been found effective in the presence of complexing agents because it can convert some low-solubility metal hydroxides to their more soluble, lower valency form, thereby eliminating radium adsorption sites. A radium level of 30 pCi/g in the tailings is concluded to be environmentally safe for surface disposal of tailings. 相似文献