Role of Peritoneal Equilibration Test in Assessing Folate Transport During Peritoneal Dialysis.

OBJECTIVES: Low plasma folate levels have been reported in patients undergoing hemodialysis and peritoneal dialysis (PD) in clinical studies. However, folate transport has never been mentioned as a factor contributing to low plasma folate levels in patients undergoing PD. The peritoneal equilibrium test (PET) assesses the plasma creatinine level and glucose transport abilities. This study aimed to evaluate the association between plasma folate levels and folate transport during PD based on PET grades. METHODS: This study recruited 50 patients who underwent PD for ≥3 months and were categorized according to PET grades. Data regarding plasma folate levels and dialysate folate were collected. The primary outcomes were the relationship between the PET grade and plasma folate level and between the PET grade and dialysate-to-plasma folate concentration ratio (D/P folate). Furthermore, the difference in the plasma folate level and D/P folate between men and women was assessed. RESULTS: The plasma folate level and the D/P folate significantly differed among the 4 PET groups (both P < .001). PET grade was significantly negatively correlated with plasma folate levels (r = -0.56, P < .001) and positively correlated with D/P folate (r = 0.686, P < .001). In subgroup analysis, neither the plasma folate level nor the D/P folate significantly differed between men and women. CONCLUSIONS: Our study provides clinical evidence that the PET grade is associated with the plasma folate level and D/P folate, regardless of sex. Larger cohort studies are warranted to assess the importance of folate supplementation during PD based on PET grades.

Effects of Lethal Bronzing Disease, Palm Height, and Temperature on Abundance and Monitoring of Haplaxius crudus.

Insect vector feeding preference and behavior play important roles in pathogen transmission, especially for pathogens that solely rely on insect vector transmission. This study aims to examine the effects of the 16SrIV-D phytoplasma, the causal agent of lethal bronzing (LB) disease of palms, on associated auchenorrhynchan insects. The numbers of auchenorrhynchans collected during weekly surveys during a yearlong study using yellow sticky traps were analyzed. The cumulative number of H. crudus was 4.5 times greater on phytoplasma-infected relative to non-infected palms. Other auchenorrhynchans showed no difference between phytoplasma-infected and non-infected palms or were greater on non-infected rather than on infected palms. Furthermore, we examined the effects of LB, palm height, temperature, and the interactive effects of these factors on H. crudus abundance. When the palms were infected with LB, at low temperature, H. crudus was more abundant on shorter than taller palms; however, H. crudus was more abundant on taller than shorter palms at the median and higher temperatures. These results may indicate that H. crudus prefers LB-infected palms over non-infected palms. The interactive effects of LB, palm heights, and temperature further suggest that vector monitoring and disease management should be optimized according to seasonal variation in temperature.

Comparative study of audio spatializers for dual-loudspeaker mobile phones.

MPEG-1, layer 3 handsets equipped with dual loudspeakers and three-dimensional audio modules have received much attention in the market of consumer electronics. To create spatial impression during audio reproduction, the head-related transfer function (HRTF) and the crosstalk cancellation system (CCS) are key elements in many audio spatializers. However, there are many factors that one should take into account during the design and implementation stages of an audio spatializer in the handset application. In the paper, a comprehensive study was undertaken to compare various audio spatializers for use with dual-loudspeaker handsets, in the context of inverse filtering strategies. Two deconvolution approaches, the frequency-domain method and the time-domain method, are employed to design the required inverse filters. Different approaches to design audio spatializers with the HRTF, CCS, and their combination are compared. In particular, two modified CCS approaches are suggested. Issues in the implementation phase such as regularization, complex smoothing, and structures of inverse filters are also addressed in the paper. Comprehensive objective and subjective tests were conducted to investigate the aforementioned aspects of audio spatializers. The data obtained from the subjective tests are processed by using the multianalysis of variance to justify statistical significance of the results.

Objective and subjective analysis of effects of listening angle on crosstalk cancellation in spatial sound reproduction.

A comprehensive study was conducted to explore the effects of listening angle on crosstalk cancellation in spatial sound reproduction using two-channel stereo systems. The intention is to establish a sustainable configuration of crosstalk cancellation system (CCS) that best reconciles the separation performance and the robustness against lateral head movement, not only in theory but also in practice. Although crosstalk can in principle be suppressed using multichannel inverse filters, the CCS does not lend itself very well to practical application owing to the fact that the sweet spot is being so small. Among the parameters of loudspeaker deployment, span angle is a crucial factor that has a profound impact on the separation performance and sweet spot robustness achievable by the CCS. This paper seeks to pinpoint, from a more comprehensive perspective, the optimal listening angle that best reconciles the robustness and performance of the CCS. Two kinds of definitions of sweet spot are employed for assessment of robustness. In addition to the point source model, head related transfer functions (HRTF) are employed as the plant models in the simulation to emulate more practical localization scenarios such as the high-frequency head shadowing effect. Three span angles including 10, 60, and 120 deg are then compared via objective and subjective experiments. The Friedman test is applied to analyze the data of subjective experiments. The results indicate that not only the CCS performance but also the panning effect and head shadowing will dictate the overall performance and robustness. The 120-deg arrangement performs comparably well as the standard 60-deg arrangement, but is much better than the 10-deg arrangement.

Optimal design of loudspeaker arrays for robust cross-talk cancellation using the Taguchi method and the genetic algorithm.

An optimal design technique of loudspeaker arrays for cross-talk cancellation with application in three-dimensional audio is presented. An array focusing scheme is presented on the basis of the inverse propagation that relates the transducers to a set of chosen control points. Tikhonov regularization is employed in designing the inverse cancellation filters. An extensive analysis is conducted to explore the cancellation performance and robustness issues. To best compromise the performance and robustness of the cross-talk cancellation system, optimal configurations are obtained with the aid of the Taguchi method and the genetic algorithm (GA). The proposed systems are further justified by physical as well as subjective experiments. The results reveal that large number of loudspeakers, closely spaced configuration, and optimal control point design all contribute to the robustness of cross-talk cancellation systems (CCS) against head misalignment.