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Background: Treatment of hypertension should be continuous, and patients should be closely monitored for treatment adherence. However, non-compliance still exists globally. This study aimed to determine treatment adherence among patients aged ≥60 years with hypertension and its associated factors in an urban district of Ho Chi Minh City, Vietnam. Methods: A cross-sectional study evaluated treatment adherence in two areas: medication and non-pharmacological adherence. Medication adherence was measured using the 8-item Morisky Medication Adherence Scale. Non-pharmacological adherence was based on the Ministry of Health guidelines for hypertension treatment and assessed by lifestyle changes, including smoking cessation, alcohol consumption restriction, reduced salt intake, increased physical activity, and regular follow-up visits. Results: A total of 537 people participated in the study, of whom females accounted for the majority (63.7%), and patients aged 60–70 years old accounted for 50%. The proportion of patients with medication adherence was 11.7%. The percentages of patients who adhered to non-smoking and limited alcohol intake were 93.5% and 92.9%, respectively. A total of 76.9% of patients underwent regular check-ups. The proportion of patients who adhered to moderate and high levels of physical activity was 64.3%. Patients who were compliant with salt intake reduction accounted for 63.1%. Factors related to antihypertensive drug adherence included disease duration and chronic comorbidities. Factors associated with non-drug adherence included health insurance, comorbidities, and nutritional status. Conclusions: Intervention programs to increase hypertension treatment adherence among elderly patients should focus on educating drug adherence and salt reduction, especially in long-standing and comorbidities patients.

The present work is a continuing study on anomalous properties of the ferroelectric nanocomposite from triglycine sulfate (TGS) and oxidized multiwalled carbon nanotubes (OMWCNT). In this study, the nature of frequency response in a region of 102–107 Hz at low temperatures (63–273 K) will be clarified by analyzing structural changes when reducing temperature. It was found that the interaction between TGS and OMWCNT inhibited the switching of SO4- groups, leading to a significant increase in relaxation time, activation energies and coercive fields. Consequently, the domain – wall freezing occurred at higher temperatures than those in pure TGS. [ABSTRACT FROM AUTHOR]

The present study is devoted to analyzing effects of high contents (85 wt.%) of dielectric inclusions, including nanocellulose and silicon dioxide nanoparticles, on ferroelectricity of composites which are made by combining dimethylammonium aluminum sulfate hexahydrate with each of them. The obtained results revealed that in the case of using nanocellulose, the ferroelectricity was not detected in fresh composite samples, but then gradually appeared over time. Meanwhile, the ferroelectricity was not observed in the composite with silicon dioxide during the observation time. [ABSTRACT FROM AUTHOR]

For the first time, a composite based on a ferroelectric metal-organic framework of [NH4][Zn(HCOO)3] combined with nanocellulose at different cellulose concentrations from 0 to 75 wt% was synthesised to investigate the changes over time in phase transition and ferroelectric switching. A comparative study for fresh samples and the samples after 288 h was conducted. Electrophysical parameters were measured in a temperature range of 140 to 245 K under a weak electric field with an amplitude of 2 V.cm−1 at a frequency of 1 kHz. The results indicated that the increase in cellulose content led to increasing the phase transition temperature from 190.1 to 238.5 K. Besides, the coercive field was also found to increase from 3.78 to 14.12 kV.cm−1 along with the reduction of dielectric permittivity and maximum polarisation. After 288 h, this phase transition decreased significantly over time even to 231.6 K in the case of highest cellulose content (75 wt%). Meanwhile, the coercive field was found to decrease from 14.12 to 10.57 kV.cm−1. Remarkable changes were detected for samples with cellulose content of higher 25 wt%. The weaker interaction between ferroelectric part and cellulose over time due to the softness of cellulose was responsible for the obtained phenomena. [ABSTRACT FROM AUTHOR]

For the first time, a composite based on a ferroelectric metal-organic framework of [NH4][Zn(HCOO)3] combined with nanocellulose at different cellulose concentrations from 0 to 75 wt% was synthesised to investigate the changes over time in phase transition and ferroelectric switching. A comparative study for fresh samples and the samples after 288 h was conducted. Electrophysical parameters were measured in a temperature range of 140 to 245 K under a weak electric field with an amplitude of 2 V.cm−1 at a frequency of 1 kHz. The results indicated that the increase in cellulose content led to increasing the phase transition temperature from 190.1 to 238.5 K. Besides, the coercive field was also found to increase from 3.78 to 14.12 kV.cm−1 along with the reduction of dielectric permittivity and maximum polarisation. After 288 h, this phase transition decreased significantly over time even to 231.6 K in the case of highest cellulose content (75 wt%). Meanwhile, the coercive field was found to decrease from 14.12 to 10.57 kV.cm−1. Remarkable changes were detected for samples with cellulose content of higher 25 wt%. The weaker interaction between ferroelectric part and cellulose over time due to the softness of cellulose was responsible for the obtained phenomena. [ABSTRACT FROM AUTHOR]

The work provides a joint theoretical and experimental approach to explore the structural contributions to ferroelectricity for an amino acid-based ferroelectric of glycine silver nitrate (GSN). The experiments included Fourier-transform infrared spectroscopy (FTIR) and dielectric spectroscopy. The theoretical analysis was conducted by using hyperbolic law (HL). Unlike the published works, the obtained results indicated that the origin of structural changes when reducing temperature in GSN is related to the N-H deformation of glycine due to the enhanced role of defects. [ABSTRACT FROM AUTHOR]

The present work reports the experimental results of studying linear and nonlinear dielectric properties of a ferroelectric nanocomposite from RbNO3 embedded in pores of an Al2O3 matrix. The dielectric relaxation times were determined above and below the phase transition temperature of pure RbNO3 (436 K). It was shown that for RbNO3 incorporated into nanosized pores of the Al2O3 matrix, a decrease in the phase transition temperature and a change in relaxation times were observed. [ABSTRACT FROM AUTHOR]

For the first time, the dielectric relaxation and domain-wall freezing are reported for the single crystal of (CH3NH3)5Bi2Cl11 ferroelectric, which was tested in wide ranges of frequency (1 Hz–1 GHz) and temperature (50–350 K). The results demonstrated two relaxation regions obeying the Arrhenius and Vogel-Fulcher-Tammann laws. The freezing temperature was estimated at 86,3 K using extrapolation method. [ABSTRACT FROM AUTHOR]

For the first time, a composite from cellulose nanoparticles (CNP) and a classical ferroelectric of glycine silver nitrate (G-Ag-N) were synthesized for investigation of structural contributions to ferroelectricity using experimental methods (X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), dielectric spectroscopy) and theoretical analysis with hyperbolic law (HL). It was figured out that the presence of cellulose inhibited the formation of G-Ag-N crystals in the composite and dragged the Curie point toward higher temperatures. Besides, the increase in CNP content led to reducing the contributions of lattice and reversible domain-wall motion to dielectric permittivity; and enhanced the role of defects. [ABSTRACT FROM AUTHOR]