Studies on physico-mechanical behaviour of kenaf/glass fiber reinforced epoxy hybrid composites

In this study, various treated, untreated, and treated kenaf/glass fiber composites were fabricated using epoxy resin. A portion of kenaf fibers were subjected to treatment with alkali, sub-portion was taken for benzoyl peroxide and potassium permanganate prior to composite fabrication. This treatment on the composite material was undertaken to achieve improved modification of the interface between the matrix and fiber bond. A portion of the glass fiber was used for enhancing the mechanical properties of the hybrid composite. The tensile strength, flexural, density, water absorption and chemical resistance of the composites were analyzed using standard methods. FTIR was conducted on the fiber to ascertain the chemical treatment on the fibers, FESEM was used for the morphological study. The results obtained showed that the tensile and flexural strength improved from 46.45-298.3 kgf, and 10.5-54.7 kgf, respectively, in the composite samples. Chemical resistance of the kenaf fiber treated potassium permanganate composite improved compared to the untreated fiber composite in both cases. The density and water absorption properties of the composites were found to decrease in the treated fibers compared to untreated fiber composites, this treated composites showed less water absorption and density. The FTIR result revealed that reaction has taken place between the fiber and the treatment reagent. Hence, fiber modification has improved the properties of the composites due to increase in fiber-matrix interaction.                     KEY WORDS: Chemical properties, Epoxy resin, Hybrid, Kenaf, Mechanical strength, Natural fiber   Bull. Chem. Soc. Ethiop. 2021, 35(1), 171-184. DOI: https://dx.doi.org/10.4314/bcse.v35i1.15

Assessment of metal availability in dumpsite soil using neutron activation analysis

No Abstract.

Impact of adherence to treatment with tiotropium and fluticasone propionate/salmeterol in chronic obstructive pulmonary diseases patients

OBJECTIVE

Poor adherence to treatment may contribute to the treatment gap in chronic obstructive pulmonary diseases (COPD). The aim of the current study was to describe the association between adherence to treatment and the risk of COPD moderate (ME) and severe (SE) exacerbations, and health care utilization.

RESEARCH DESIGN AND METHODS

Observational single cohort study utilizing the Quebec Provincial Health Insurance databases. All patients older than 40 years with a diagnosis of COPD between 2001 and 2010 were entered in the study cohort at the time of their first prescription for tiotropium (TIO) alone or co-administered with fluticasone propionate/salmeterol (TIO + FSC). Follow-up continued to the last known claim or death. Adherence was measured by the medication possession ratio (MPR) ≥80% and persistence defined as no treatment gap ≥30 days.

MAIN OUTCOME MEASURES

ME was defined as use of an oral corticosteroid or antibiotic, SE as COPD related hospitalization or an emergency room (ER) visit. COPD related health care resource utilization ascertained was prescription of rescue medications, ER visits, hospitalizations, intensive care unit (ICU) admissions, intubations, and general practitioner (GP) and respirologist visits.

RESULTS

There were 23,707 patients included in this study. Compliance and persistence with TIO for monotherapy patients were 61.1% and 47.6% respectively. For patients treated with TIO + FSC, compliance and persistence for TIO were 62.9% and 45.3% respectively, and for FSC they were 35.4% and 33.0%. Multivariate analyses showed a significant (P < 0.001) adjusted odds ratios for ME (OR(ME)) and SE (OR(SE)) for TIO compliant vs. non-compliant patients (TIO: OR(ME) = 0.543, OR(SE) = 0.712; TIO + FSC: OR(ME) = 0.436, OR(SE) = 0.570). Similarly for FSC compliance: OR(ME) = 0.546; OR(SE) = 0.749. Similar results were observed for persistence. Compliance and persistence with TIO and FSC were associated with significantly reduced rates of health care utilization.

CONCLUSIONS

Despite the typical limitations of an administrative database study, the results of this large population-based study have shown that reduced adherence to treatment with TIO and FSC is associated with increased risk for exacerbations and higher health care utilization in COPD patients.

Impact of adherence to treatment with fluticasone propionate/salmeterol in asthma patients

OBJECTIVE

Low adherence with asthma treatment may be associated with suboptimal outcomes and hence create a treatment gap in the real-life setting. The objective of this study was to assess the long-term association between adherence to treatment with fixed-dose fluticasone propionate/salmeterol (FSC) and the risk of exacerbations and health care utilization in patients with asthma.

RESEARCH DESIGN AND METHODS

Observational single cohort study utilizing the Quebec Health Insurance databases. All patients (age >12 years) with a diagnosis of asthma (ICD9-CM 493.xx) between 2001 and 2010 were entered into the study cohort at the time of their first prescription for FSC at any dose. Follow-up continued to the last known claim or death. Adherence to treatment was ascertained as compliance (medication possession ratio ≥80%) and persistence (absence of treatment gap ≥30 days).

MAIN OUTCOME MEASURES

Outcomes assessed were exacerbations defined as one of the following: use of oral corticosteroid (OCS), emergency room (ER) visit for asthma or hospitalization for asthma. Asthma related health care resource utilizations ascertained were number of prescription claims for rescue medications, ER visits, hospitalizations, intensive care unit (ICU) stay, intubations, and general practitioner (GP) and respirologist visits.

RESULTS

A total of 19,126 patients were included in the study. The proportion of compliant and persistent patients were 42.7% and 29.3% respectively. Multivariate logistic regression analyses showed a significantly reduced adjusted odds of exacerbations for compliant (OR = 0.48; 95% CI: 0.44-0.54) and persistent patients (OR = 0.42; 95% CI: 0.38-0.48). Similarly, significantly lower rates of health care utilization were observed for compliant and persistent patients.

CONCLUSIONS

The results of this large population-based study have shown that increased adherence to treatment with FSC is associated with lower risk for exacerbations, lower rescue medication use and lower health care utilization in asthma patients. Despite the typical limitations of an administrative database study including validity of the diagnosis, the fact that compliance and persistence are calculated based on filled claims which does not guarantee that the patients actually took their medications, and the absence of clinical and laboratory data, the findings have implications for physician and patient awareness of the importance of adherence in the management of asthma.