RESUMEN

This work reports the design and development of an efficient sillenite based visible light photoactive Bi24Ga2O39-TiO2 (BGT) heterostructure. Structural and morphological studies based on X-ray diffraction (XRD) and high-resolution scanning electron microscopy (HRSEM) confirm the formation of combined phase as well the overall morphology of composite BGT. Additionally, X-ray photoelectron spectroscopy (XPS) results confirm the presence of Bi3+, Ga3+, Ti4+ & O2-. The composite exhibits a shift in the absorbance edge towards visible region of electromagnetic spectrum when compared to that of TiO2. Suitable band edge positions in the composite facilitate the formation of type-1 heterojunction enhancing visible light photocatalytic property. The photocatalytic activity is evident from photo reduction of Cr (VI) (95% reduction in 180 min). The composite also plays an improved and effective role in the degradation of persistent drug ampicillin-cloxacillin (AMC) with a rate constant of 0.02 min-1. Photocatalytic experiments conducted at different pH values showed higher performance at lower pH ∼3. Trapping experiments performed on the sample confirm the role of holes as the main active species during photocatalysis. Appreciable recyclability of BGT composite was noted with respect to AMC drug degradation.

Asunto(s)

Luz Solar , Titanio , Catálisis , Titanio/química , Ampicilina

RESUMEN

INTRODUCTION: The aim of this study is to evaluate the association of vitamin D deficiency and pelvic floor disorders (PFD) including pelvic organ prolapse (POP) and stress urinary incontinence in postmenopausal women. MATERIALS AND METHODS: This is a prospective case control study on 120 women with or without symptoms of PFD. Relevant history and clinical examination were conducted. Serum 25-hydroxy vitamin D levels were measured in all women. Chi square and student t test were used to test significance of association. Logistic regression was used to adjust for age. Odds ratios and 95% confidence intervals were calculated. RESULTS: Of the 120 postmenopausal women included, 51 had PFD on clinical examination. Of the 51 cases, 28 women had POP and 14 women had stress incontinence (SUI) while nine women had both POP and SUI. The study showed that vitamin D levels were significantly lower in women with PFD than those without PFD. Menopausal status of more than 5 years was also significantly associated with PFD. CONCLUSION: Findings suggest association of vitamin D deficiency and PFD in postmenopausal women. In addition, postmenopausal women have a high prevalence of vitamin D deficiency indicating a need to evaluate vitamin D levels in these women.