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Background This cross-sectional analytical study aimed to assess the level of knowledge on dietary management of chronic kidney disease (CKD) among patients undergoing hemodialysis in a tertiary care hospital in Puducherry, South India. Methodology The study was conducted among 86 inpatients diagnosed with CKD and undergoing hemodialysis in the dialysis unit. They were selected by simple random sampling. The self-administered, validated, self-structured questionnaire was used to collect the data. The study was conducted from May to September 2019. Descriptive statistics (frequency, percentage, mean, and standard deviation) and inferential statistics (chi-square) were used to find out the relationship between the level of knowledge and background variables using IBM SPSS Statistics for Windows, Version 25.0 (Released 2017; IBM Corp., Armonk, New York, United States). Results The findings indicated that the majority of patients were in the 20-30 age range (36, 41.9%), male (58, 67.4%), from nuclear families (58, 66.3%), with mixed dietary habits (60, 69.8%), and undergoing thrice-weekly hemodialysis (34, 53.5%). Additionally, 59 (68.6%) were hypertensive and 14 (16.3%) were diabetic. Most patients exhibited a moderate level of knowledge (74, 86%), while a small percentage had inadequate (6, 7%) and adequate (6, 7%) knowledge, with a mean (SD) value of 2.00 (0.376). The study identified statistically significant associations between knowledge levels and age, occupation, food habits, duration of dialysis, pre-existing co-morbid illnesses, and treatment of hemodialysis with a p-value <0.05. Conclusions In conclusion, this study highlights that the majority of the CKD patients undergoing hemodialysis exhibit moderately adequate knowledge of dietary management. However, a notable need remains for further education and support in this area. Addressing these knowledge gaps is crucial, as it can empower nursing students and healthcare professionals to educate these patients on their dietary needs effectively. By providing comprehensive education and support, we can enhance the quality of care and improve outcomes for hemodialysis patients.
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The composite processing technique and nanofiller concentration and its functionalization significantly alter the properties of polymer nanocomposites. To realize this, multi-walled carbon nanotubes (CNT) were dispersed in a poly(vinylidene fluoride) (PVDF) matrix at carefully selected CNT concentrations by two illustrious methods, such as solution-cast and melt-mixing. Notwithstanding the processing method, CNTs induced predominantly the γ-phase in PVDF, instead of the commonly obtained ß-phase upon nanofiller incorporation, and imparted significant improvements in dielectric properties. Acid-treatment of CNT improved its dispersion and interfacial adhesion significantly with PVDF, and induced a higher γ-phase content and better dielectric properties in PVDF as compared to pristine CNT. Further, the γ-phase content was found to be higher in solution-cast composites than that in melt-mixed counterparts, most likely due to solvent-induced crystallization in a controlled environment and slow solvent evaporation in the former case. However, interestingly, the melt-mixed composites showed a significantly higher dielectric constant at the onset of the CNT networked-structure as compared to the solution-cast composites. This suggests the possible role of CNT breakage during melt-mixing, which might lead to higher space-charge polarization at the polymer-CNT interface, and in turn an increased number of pseudo-microcapacitors in these composites than the solution-cast counterparts. Notably, PVDF with 0.13 vol% (volume fraction, f c = 0.0013) of acid-treated CNTs, prepared by melt-mixing, displayed the relative permittivity of â¼217 and capacitance of â¼5430 pF, loss tangent of â¼0.4 at 1 kHz and an unprecedented figure of merit of â¼10(5). We suggest a simple hypothesis for the γ-phase formation and evolution of the high dielectric constant in these composites. Further, the high-dielectric composite film showed marked improvements in mechanical and thermal properties over the neat PVDF film. These composites with exceptional dielectric properties and concomitant improvement in mechanical and thermal properties offer a great promise for use in flexible and mechanically robust charge storage devices.
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Electromagnetic interference (EMI) shielding properties in the 1-18 GHz frequency range for multi-walled carbon nanotube (MWNT)-poly(vinylidene fluoride) (PVDF) composites are reported. A simple and gentle acid-treatment of MWNT showed a percolation threshold (PT) of 0.15 wt% in the PVDF matrix as against 0.35 wt% for unfunctionalized MWNT. Acid-treatment of MWNT significantly improves dispersion, interfacial adhesion with the matrix and the EMI shielding properties of PVDF composites. Further, the EMI shielding properties are correlated with the electrical properties. Using composite films of 0.3 mm thickness, the maximum shielding effectiveness (SET) values for 4 wt% unfunctionalized MWNT composites are found to be about 110, 45, 30, 26, and 58 dB for L (1-2 GHz), S (2-4 GHz), C (4-5.8 GHz), J (5.8-8 GHz), and X (8-12 GHz) bands, while the corresponding values for only 0.5 wt% acid functionalized MWNT composites are about 98, 45, 26, 19, and 47 dB, respectively. The electrical conductivity for both the cases is â¼10(-3) S cm(-1) and the weight contents of CNTs are higher than the PT for the respective composites. The comparable EMI SE and electrical conductivity values for both the composites at different weight fractions of CNTs suggest that there is a critical electrical conductivity above which the composites attain improved EMI shielding properties. Further, the shielding mechanism was found to be dominated by absorption loss. Therefore, the composites may also serve as a radar absorbing material.
