Adsorption of fluoride on a green adsorbent derived from wastepaper: Kinetic, isotherm and characterisation study

The excessive concentration of fluoride (F−) in water represents a grave problem for several countries, especially those that depend on groundwater as a main source of drinking water. Therefore, many treatment methods, such as chemical precipitation and membrane, were practised to remove F− from water. However, the traditional methods suffer from many limitations, such as the high cost and the slowness. Hence, many studies have been directed towards developing novel and effective water defluoridation methods. In this context, the current study investigates the development of an eco-friendly adsorbent by extracting Ca, Al, and Fe from industrial by-products, precipitating them on sand particles, and using this new adsorbent to remove F− from water. The removal experiments were commenced under different pH levels (3-10), contact times (0–240 minutes) and concentrations of F− (7.5–37.5 mg/L). X-ray fluorescence (XRF), X-ray diffraction Investigator (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray Spectroscopy (EDX) methods were used to characterise the green adsorbent. Adsorption isotherm and kinetic studies were also conducted to define the adsorption type. The results confirmed that the new adsorbent could remove as high as 86% of F− at pH, contact time, agitation speed and adsorbent dose of 10, 180 minutes, 200 rpm and 15 mg/L, respectively. The characterisation studies prove the occurrence of the sorption process and the suitability of the morphology of the adsorbent for F− removal. Adsorption kinetics follow better with a pseudo-first-order model that indicates the predominance of physisorption, which agrees with the FTIR results. The isotherm study indicated that Langmuir isotherm is more suitable for representing data with an R2 value of 0.992, which means the adsorption of F− occurs as monolayer adsorption on homogeneous sites on the surface of the new adsorbent. In summary, it can be concluded that the developed adsorbent in this study could be a promising alternative to the traditional F− removal methods

Sphingomyelin phosphodiesterase-1 (SMPD1) coding variants do not contribute to low levels of high-density lipoprotein cholesterol

<p>Abstract</p> <p>Background</p> <p>Niemann-Pick disease type A and B is caused by a deficiency of acid sphingomyelinase due to mutations in the sphingomyelin phosphodiesterase-1 (<it>SMPD1</it>) gene. In Niemann-Pick patients, <it>SMPD1 </it>gene defects are reported to be associated with a severe reduction in plasma high-density lipoprotein (HDL) cholesterol.</p> <p>Methods</p> <p>Two common coding polymorphisms in the <it>SMPD1 </it>gene, the G1522A (G508R) and a hexanucleotide repeat sequence within the signal peptide region, were investigated in 118 unrelated subjects of French Canadian descent with low plasma levels of HDL-cholesterol (< 5^thpercentile for age and gender-matched subjects). Control subjects (n = 230) had an HDL-cholesterol level > the 25^thpercentile.</p> <p>Results</p> <p>For G1522A the frequency of the G and A alleles were 75.2% and 24.8% respectively in controls, compared to 78.6% and 21.4% in subjects with low HDL-cholesterol (<it>p </it>= 0.317). The frequency of 6 and 7 hexanucleotide repeats was 46.2% and 46.6% respectively in controls, compared to 45.6% and 49.1% in subjects with low HDL-cholesterol (<it>p </it>= 0.619). Ten different haplotypes were observed in cases and controls. Overall haplotype frequencies in cases and controls were not significantly different.</p> <p>Conclusion</p> <p>These results suggest that the two common coding variants at the <it>SMPD1 </it>gene locus are not associated with low HDL-cholesterol levels in the French Canadian population.</p

Predictors of Leadership Competencies Among Nurse Executives in the Kingdom of Saudi Arabia

Yousef A Alshamlani,1,&ast; Naif H Alanazi,2,&ast; Sami A Alhamidi,2,&ast; Raeed A Alanazi,2,&ast; Atallah Alenezi,3,&ast; Norisk M Adalin,1,&ast; Seham M Alyousef,2,&ast; Regie B Tumala2,&ast; 1Nursing Department, King Saud University Medical City, Diriyah, Riyadh, Kingdom of Saudi Arabia; 2College of Nursing, King Saud University, Diriyah, Riyadh, Kingdom of Saudi Arabia; 3Nursing Department, College of Applied Medical Sciences, Shaqra University, Shaqra, Kingdom of Saudi Arabia&ast;These authors contributed equally to this workCorrespondence: Regie B Tumala, College of Nursing, King Saud University, Diriyah, Riyadh, 11421, Kingdom of Saudi Arabia, Tel +966554773976, Email [email protected]: Awareness and development of nurse executives’ leadership competencies has been considered a key strategy for the success of healthcare organizations. However, only a few studies about nurse executives’ leadership competencies are available in the literature, and no study has been conducted about the topic within Saudi Arabian context. The aim of this study was to assess the leadership competencies of nurse executives and the predictors of these competencies.Methods: This quantitative study used a descriptive, cross-sectional, and correlational design. The study recruited a total convenience sample of 136 nurse executives who voluntarily consented to participate. The respondents self-rated the online survey, “Leadership Competency Assessment Tool: Self-Assessment.” Data collection was conducted between September 2022 and November 2022. Test of correlation and multiple regression analyses were conducted.Results: The overall mean score of nurse executives’ leadership competencies was 3.38 out of 5.0, which was below the level of having excellent leadership competencies. Four dimensions had mean scores below the level of having excellent leadership competencies, namely, communication and relationship building (3.48), knowledge of the healthcare environment (3.29), leadership (3.45), and business skills (3.15), while nurse executives had excellent leadership competencies only in the professionalism dimension (3.51). Age (p=0.04), highest educational attainment (p=0.01), current role (p< 0.01) and length of experience (p=0.02) as nurse executive, monthly salary (p=0.03), nationality (p=0.04), and having seminars/trainings in leadership and management (p=0.01) were considered predictors of the leadership competencies of nurse executives.Conclusion: Nurse executives reported a low level of leadership competencies, thus implying necessary actions for improvement. There were personal factors that influenced the level of nurse executives’ leadership competencies. To achieve quality outcomes and maintain a high level of nursing care in hospital organizations, these findings must be considered in planning strategies related to the improvement of the leadership competencies of nurse executives.Keywords: assessment, leadership competencies, nurse executives, predictors, Saudi Arabi