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1.
Appl Radiat Isot ; 194: 110624, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36774822

RESUMEN

The goal of the current research was to define the impact of individual characteristics on the response of osteoporosis patients to bisphosphonate medication, as well as the influence of gender on changes in the bone mineral density (BMD).The DXA scan was used to assess a group of 647 osteoporosis patients (533 females and 114 males) who visited the St Bartholomew's Hospitals and Royal London osteoporosis clinics. All male subjects received statistically substantial increases in BMD relative to baseline values after two years of therapy. When compared to prior therapy, men's BMD of the lumbar spine (LS) and hip joint (HJ) rose by 0.057 g/cm2 (6.9%, p0.001) and 0.021 g/cm2 (2.48 percent, p0.001), respectively.. Female patients had BMD changes of 0.028 g/cm2 (3.58 percent, p0.001 vs. prior therapy) and -0.006 g/cm2 (-0.78 percent, p0.001 vs. before treatment) in the lumbar spine and hip, respectively. Male patients exhibited a greater increase in BMD than female patients due to ovarian failure and significant oestrogen loss, which speeds up bone resorption by 90% following menopause, according the research findings.


Asunto(s)
Densidad Ósea , Osteoporosis , Humanos , Masculino , Femenino , Densidad Ósea/fisiología , Absorciometría de Fotón/métodos , Vértebras Lumbares , Difosfonatos
2.
Environ Res ; 216(Pt 3): 114706, 2023 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-36336094

RESUMEN

Silver nanoparticles (AgNPs) are often used as antibacterial agents. Here, graphene-silver nanoparticles (G-Ag) and graphene-silver nanoparticles poly-vinylpyrrolidone (G-AgPVPy) were prepared by chemical reduction and in-situ polymerization of vinylpyrrolidone (VPy). The prepared G-Ag and G-AgPVPy composites were characterized using various techniques. The size of the AgNPs on the graphene surface in the prepared G-Ag and G-AgPVPy composites was measured as ∼20 nm. The graphene sheets size in the G-Ag and G-AgPVPy composites were measured as 6.0-2.0 µm and 4.0-0.10 µm, respectively, which are much smaller than graphene sheets in graphite powder (GP) (10.0-3.0 µm). The physicochemical analysis confirmed the formation of G-Ag and G-AgPVPy composites and even the distribution of AgNPs and PVPy on the graphene sheets. The synthesized composites (G-AgPVPy, G-Ag) exhibited a broad-spectrum antibacterial potential against both Gram-negative and Gram-positive bacteria. The lowest minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values were calculated as >40 µg/mL using G-Ag and GP, while G-AgPVPy showed as 10 µg/mL against Staphylococcus aureus. Among GP, G-Ag, and G-AgPVPy, G-AgPVPy disturbs the cell permeability, damages the cell walls, and causes cell death efficiently. Also, G-AgPVPy was delivered as a significant reusable antibacterial potential candidate. The MIC value (10 µg/mL) did not change up to six subsequent MIC analysis cycles.


Asunto(s)
Grafito , Nanopartículas del Metal , Grafito/química , Plata/química , Nanopartículas del Metal/química , Escherichia coli , Pruebas de Sensibilidad Microbiana , Antibacterianos/farmacología , Antibacterianos/química
3.
Environ Res ; 214(Pt 4): 113866, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35952748

RESUMEN

Hierarchical nanostructures play an important role in environmental clean-up and sustainability applications. The magnetic and photocatalytic characteristics of flower-like Mn-doped α-Fe2O3 nanostructures were prepared by using a polyol-assisted hydrothermal method. Crystallite sizes are in the range of 35-42 nm, and the existence of 3D hierarchical nanostructures was observed in FESEM pictures. The optical band gap energy varies between 2.08 and 2.16 eV, while XPS examination exposes the ions' charge states and validates Mn3+ inclusion in the Fe3+ lattice. At room temperature, the addition of Mn to α-Fe2O3 results in a spin disorder ferromagnetism and coercivity of about 600 Oe was achieved. Methylene blue (MB) dye solution degraded by 92% when 2.5% Mn doped with α-Fe2O3 under visible conditions for 120 min irradiation time.

4.
Chemosphere ; 307(Pt 1): 135712, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35843438

RESUMEN

Hydrogen is one of the cleanest renewable and environmentally friendly energy resource that can be generated through water splitting. However, hydrogen evolution occurs at high overpotential, and efficient hydrogen evolution catalysts are desired to replace state-of-the-art catalysts such as platinum. In the present work, a novel molybdenum disulfide decorated banana peel porous carbon (MoS2@BPPC) catalyst has been developed using banana peel carbon and molybdenum disulfide (MoS2) for hydrogen evolution reaction (HER). Banana peel porous carbon (BPPC) was initially synthesized from the banana peel (biowaste) by a simple carbonization method. Subsequently, 20 wt% of bare MoS2 was distributed on the pristine BPPC matrix using the dry-impregnation method. The resulting MoS2@BPPC composites were systematically investigated to determine the morphology and structure. Finally, using a three-electrode cell system, pristine BPPC, bare MoS2, and MoS2@BPPC composite were used as HER electrocatalysts. The developed MoS2@BPPC composite showed greater HER activity and possessed excellent stability in the acid solution, including an overpotential of 150 mV at a current density of -10 mA cm-2, and a Tafel slope of 51 mV dec-1. This Tafel study suggests that the HER takes place by Volmer-Heyrovsky mechanism with a rate-determining Heyrovsky step. The excellent electrochemical performance of MoS2@BPPC composite for HER can be ascribed to its unique porous nanoarchitecture. Further, due to the synergetic effect between MoS2 and porous carbon. The HER activity using the MoS2@BPPC electrode advises that the prepared catalyst may hold great promise for practical applications.


Asunto(s)
Molibdeno , Musa , Carbono , Disulfuros , Electrodos , Hidrógeno/química , Molibdeno/química , Platino (Metal) , Porosidad , Agua
5.
Environ Res ; 212(Pt B): 113273, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35439456

RESUMEN

Natural products derived carbon quantum dots (CQDs) catch huge attention owing to their distinctive properties of smaller size, water dispersibility, high photostability, lower cost, tunable emission, biocompatibility, least toxicity, electrical conductivity, optical and catalytic properties, and easy modification. Herein high fluorescent CQDs were prepared using Borassus flabellifer (ice apple) as a carbon source utilizing the simplistic one-step hydrothermal method. The prepared CQDs possessed excellent photoluminescence, high photostability, and stability in an aqueous solution and harbored large of quantum yield and strong stability in high pH conditions with the characteristic strong blue fluorescence emission. With these superior properties, the CQDs have been used as sensing probes for the detection of Fe3+ ions having excellent selectivity and sensitivity with a 2.01 µM limit of detection. The CQDs decorated probe was found effective in detecting Fe3+ ions in the tap and drinking mineral water, suggesting the applicability of the prepared sensor. The developed sensor exhibited advantages, including simple, low-cost, label-free, rapid, and good sensitivity and selectivity towards Fe3+ ions, with a great application for detection of such ions in real water.


Asunto(s)
Puntos Cuánticos , Carbono/química , Endospermo , Colorantes Fluorescentes/química , Iones , Puntos Cuánticos/química , Agua
6.
Environ Res ; 212(Pt A): 113211, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35367425

RESUMEN

A mesoporous silica hybrid functionalized with aromatic 1,2-phenyl dithiol (PT@MS NPs) was prepared in two steps such as sol-gel co-condensation of VTMS and tetraethyl orthosilicate (TEOS) using Pluronic P123 as a structure directing surfactant, and surface grafting reaction of 1,2-phenyl dithiol with vinyl groups via click-reaction. Surface area, average pore size, and mesopore volume of the produced PT@MS NPs are approximately 546 m2/g, 2.8 nm, and 0.63 cm3/g, respectively. With an adsorption quantity of 252 mg/g and a removal capacity of nearly 95% from the initial metal ion (100 mg/L of Hg2+ ions) solutions, the PT@MS NPs material showed highly selective adsorption of mercury (Hg2+) from a mixture of other competitive metal (Zn2+, Ni2+, Pb2+, Cd2+, and Fe2+) ions. By treating the adsorbent with an acidic aqueous solution (0.1 M HCl), the produced adsorbent can be recycled and reused up to five times. As a result, the PT@MS NPs adsorbent might be used in wastewater treatment as a highly efficient and selective adsorbent for harmful Hg2+ ions.


Asunto(s)
Mercurio , Contaminantes Químicos del Agua , Adsorción , Iones , Mercurio/análisis , Dióxido de Silicio/química , Agua , Contaminantes Químicos del Agua/análisis
7.
Aust Orthod J ; 27(2): 145-54, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22372271

RESUMEN

BACKGROUND: General dental practitioners (GDPs) are key clinicians in the orthodontic referral chain as they complement (and may compete with) orthodontists in providing treatment for the public. OBJECTIVES: To determine the nature and extent of GDPs' involvement in orthodontic treatment provision and to identify influences on GDPs' choice of orthodontist. METHODS: An email survey was conducted of actively-practising GDPs in May-June 2010. Two timelines of contact were followed, with non-responders to the first survey re-contacted three weeks later. RESULTS: Just under one-fifth (19.3 per cent) reported providing forms of orthodontic treatment. This proportion was higher among males, more experienced practitioners, and dentists in rural locations. The percentage involvement ranged from 22.3 per cent in Greater Auckland to 10.5 per cent in Greater Wellington and 11.9 per cent in Christchurch. In the remainder of New Zealand, percentages ranged from 11.5 per cent in urban areas to 37.1 per cent in rural areas. Of those providing treatment, almost half had 1-10 patients under management, and just over one-third had greater numbers. Sixty-one per cent of orthodontically-involved GDPs in Auckland had more than 10 orthodontic patients. The most commonly treated condition was a simple crossbite, while the least commonly treated condition was the severe Class III malocclusion. CONCLUSIONS: The provision of orthodontic treatment by New Zealand GDPs has decreased in recent years to an average of about one in five, but this figure is considerably higher in rural areas and is a notable feature of the greater Auckland area. The findings suggest that the majority of the more complex cases are continuing to be referred to specialist orthodontists.


Asunto(s)
Odontología General , Ortodoncia Correctiva , Pautas de la Práctica en Odontología , Derivación y Consulta , Conducta de Elección , Comunicación , Educación Continua en Odontología , Femenino , Humanos , Relaciones Interprofesionales , Masculino , Maloclusión/terapia , Maloclusión Clase II de Angle/terapia , Maloclusión de Angle Clase III/terapia , Nueva Zelanda , Ortodoncia/educación , Prioridad del Paciente , Ubicación de la Práctica Profesional , Calidad de la Atención de Salud , Población Rural , Factores Sexuales , Encuestas y Cuestionarios , Población Urbana
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