153 research outputs found
Ultrasound-enhanced photodegradation of Diclofenac Na
Diclofenac sodium, a non-steroidal anti-inflammatory drug, is an emerging water pollutant that cannot be removed by conventional wastewater treatment plants. Combined processes based on hydrodynamic cavitation (sonolysis) and heterogeneous photocatalysis are highly promising for the degradation and mineralization of refractory drugs [1,2]. Nevertheless, the use of nanoparticles as photocatalyst is not suitable in real applications for environmental and health hazard [3] as well as for the complex photocatalyst retrieval at the end of the process. For this reasons, we studied the photocatalyzed degradation of Diclofenac Na using micrometric titanium dioxide photocatalyst (Kronos 1077, 0.1 g/L), both bare and decorated with silver. Moreover, the synergic effect of pulsed ultrasound was tested. Initial concentrations of diclofenac sodium in the 25-50 ppm range were tested. Tests were performed in a batch jacketed reactor. A UVA lamp set sideway irradiated the solution with a power of 30 W/m2 and an ultrasonic horn (20 kHz) sonicated the solution. HPLC-UV and HPLC-MS determined Diclofenac degradation and the main byproducts. A total organic carbon analyzer (TOC, Shimadzu) calculated the fraction of Diclofenac mineralized. An example of photodegradation run is reported in figure. A positive synergy coupling ultrasounds with photocatalysis is confirmed, mainly with the use of Ag nanoparticles-TiO2. We observed both a faster molecule degradation and its complete mineralization
Sonophotocatalytic degradation of sodium diclofenac using low power ultrasound and micro sized TiO2
The nonsteroidal anti-inflammatory drug sodium diclofenac (DC) is an emerging water pollutant which resists conventional wastewater treatments. Here the sonophotocatalytic degradation of DC was carried out using micrometric TiO2 (both pristine and Ag-decorated), UV-A irradiation and 20 kHz pulsed ultrasound. Sonophotocatalytic tests were compared with photolysis, sonolysis, sonophotolysis, sonocatalysis and photocatalysis data performed in the same conditions. A synergy index of over 2 was determined for tests with pristine TiO2, while values close to 1.3 were observed for Ag-TiO2. Reaction intermediates were studied by HPLC-MS, showing degradation mechanisms activated by hydroxyl radicals. Similar pathways were identified for photocatalytic and sonophotocatalytic tests, although the latter led to more oxidized compounds. Different reactor configurations (static and dynamic set ups) were studied. Sequential and simultaneous application of UV light and ultrasound led to similar performance. The role of water matrix was investigated using ultrapure and drinking water, showing marked detrimental effects of electrolytes on the DC degradation. Overall, the combined treatment proved more efficient than photocatalysis alone especially in demanding working conditions, like in drinking water matrices
Prescribing Nirmatrelvir-Ritonavir: How to Recognize and Manage Drug-Drug Interactions
Nirmatrelvir-ritonavir (NMV/r) is now being used to treat high-risk patients with mild to moderate COVID-19. This article provides advice to clinicians regarding recognition of medications likely to interact with NMV/r and suggests approaches to managing such drug-drug interactions. An algorithm is provided to assist in decision making
LiFePO4 spray drying scale-up and carbon-cage for improved cyclability
The growing market for electrical vehicles requires inexpensive, long-lasting batteries. LiFePO4 (LFP) melt-synthesized from ore concentrate fits this role, but the manufacturing process requires additional steps that includes grinding large ingots into a nanoparticle suspension followed by a dessication step. Spray drying, rather than tray drying, creates a mesopomus powder that enhances wettability. Adding lactose and high-Mw polyvinyl alcohol (PVA) to the suspension of nanostructures followed by pyrolysis, creates a carbon-cage that interconnects the cathode nanoparticles, imparting better capacity (LiFePO4/C: 161 mA h g(-1) at 0.1C), discharge rate (flat plateau, 145 mA h g(-1) at 5C), and cyclability (91% capacity retention after 750 cycles at 1C). Particle size affects battery stability; PVA increases the suspension's viscosity and alters the powder morphology, from spherical to hollow particles. A model describes the non-Newtonian suspension's rheology changing: shear, temperature, LFP and PVA loading. Carbon precursors prevent the nanoparticles from sintering during calcination but lactose gasifies 50% of the carbon, according to the chemical and allotropic composition measurements (CS analyzer, XPS, and Raman). The carbon-cage imparts micmporosity and we correlate the SEM and TEM powder's morphology with N2 physisorption porosimetry. Ultrasonication of the suspension fragments the PVA chain, which is detrimental to the final cathode performance
Respiratory symptoms and chronic bronchitis in people with and without HIV infection
Objectives
High rates of respiratory symptoms and chronic bronchitis (CB) are reported in people with HIV infection (PWH). We investigated the prevalence of respiratory symptoms and CB in PWH and HIVânegative people in the Pharmacokinetic and clinical Observations in PeoPle over fiftY (POPPY) study.
Methods
Assessment of respiratory symptoms and CB was undertaken using the modified form of the St. Georgeâs Respiratory Questionnaire for chronic obstructive pulmonary disease (COPD). Univariate (Ï2 tests, MannâWhitney U tests and Spearmanâs rank correlation) and multivariable (linear and logistic regression) analyses were performed to consider associations of respiratory symptoms with demographic, lifestyle and HIVârelated parameters, and with depressive symptoms and quality of life.
Results
Among the 619 participants, respiratory Symptom scores were higher in older and younger PWH compared to older HIVânegative people, with median (interquartile range) scores of 17.7 (6.2, 39.5), 17.5 (0.9, 30.0) and 9.0 (0.9, 17.5), respectively (P = 0.0001); these differences remained significant after confounder adjustment. Sixtyâthree participants (10.2%) met the criteria for CB [44 (14.0%) older PWH, 14 (9.2%) younger PWH, and five (3.3%) older HIVânegative people; P = 0.002], with these differences also remaining after adjustment for confounding variables, particularly smoking status [older vs. younger PWH: odds ratio (OR) 4.48 (95% confidence interval (CI) 1.64, 12.30); P = 0.004; older PWH vs. HIVânegative people: OR 4.53 (95% CI 1.12, 18.28); P = 0.03]. Respiratory symptoms and CB were both associated with greater depressive symptom scores and poorer quality of life. No strong associations were reported between CB and immune function, HIV RNA or previous diagnosis of any AIDS event.
Conclusions
Respiratory symptoms and CB are more common in PWH than in demographically and lifestyleâsimilar HIVânegative people and are associated with poorer mental health and quality of life
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