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A novel quantitative methodology to determine the partition coefficients of neutral weak bases is developed. This new electrochemical approach is based on the measurement of the total transferred charge across the oil | water interface under forced hydrodynamic conditions. The complete procedure has been validated by computational simulations and experimental results (Tylosin A). In addition, flow pattern caused inside the electrochemical cell was simulated with computational fluid dynamics using finite element methods and correlated with experimental results obtained by magnetic resonance imaging. [ABSTRACT FROM AUTHOR]

The main aspects related to the charge transfer reactions occurring at the interface between two immiscible electrolyte solutions (ITIES) are described. The particular topics to be discussed involve simple ion transfer. Focus is given on theoretical approaches, numerical simulations, and experimental methodologies. Concerning the theoretical procedures, different computational simulations related to simple ion transfer are reviewed. The main conclusions drawn from the most accepted models are described and analyzed in regard to their relevance for explaining different aspects of ion transfer. We describe numerical simulations implementing different approaches for solving the differential equations associated with the mass transport and charge transfer. These numerical simulations are correlated with selected experimental results; their usefulness in designing new experiments is summarized. Finally, many practical applications can be envisaged regarding the determination of physicochemical properties, electroanalysis, drug lipophilicity, and phase-transfer catalysis. [ABSTRACT FROM AUTHOR]

Introduction: The Early Career Medical Physicists Special Interest Group (SIG_FREC) that operates within EFOMP aims to represent individuals with less than 10 years of experience working as medical physics professionals. The purpose of this survey was to better understand the specific needs and expectations of early-career medical physicists across Europe. The aim of this study was to allow these early-career professionals to voice their ideas within EFOMP and provide insights into their challenges and opportunities while also providing them with the possibility of making suggestions for the growth of the SIG. Doing this, the members can be better equipped to be future leaders of the Medical Physics profession in their own country and in Europe., Methods: The Steering Committee of SIG_FREC developed a questionnaire and distributed it to its members., Results: Out of the total number of members of the SIG_FREC at the time of the questionnaire (97 members), 42 of them responded to the survey yielding a response rate of 43%. These provided valuable insights based on their experiences about medical physics in their country., Conclusion: The responses to the questionnaire provided a snapshot of the opinion of early-career medical physicists, representing a wide geographical distribution across Europe. The feedback from SIG_FREC members highlighted potential future operations within EFOMP., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Associazione Italiana di Fisica Medica e Sanitaria. Published by Elsevier Ltd. All rights reserved.)

The fate and degradation of 28 multiple-class veterinary pharmaceuticals in an on-farm pig slurry treatment plant based on solid-liquid separation and a nitrification-denitrification (NDN) sequence batch reactor (SBR) were evaluated for the first time. The pharmaceuticals detected at the highest concentrations in raw pig slurries belonged to the group of tetracycline antibiotics. Fluoroquinolone, lincosamide and pleuromutilin antibiotics and other drugs such as flubendazole and flunixin were also frequently detected. After solid-liquid separation, target compounds were distributed in an average of 64% onto the liquid fraction. Pharmaceuticals distributed in this fraction were removed in an average of almost 50% after being treated in NDN-SBR. Lincomycin was the compound with the highest removal percentage, reaching 100% reduction, while tetracyclines and fluoroquinolones showed moderate removal percentages (50 and 40%, respectively). Regarding nitrogen removal, NDN-SBR reduced a 77% of the content of this nutrient in the liquid slurry fraction., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

1. Indomethacin was administered alone or in addition to either diuretic or propranolol therapy to three groups of patients with essential hypertension on a free sodium diet. 2. Indomethacin administration reduced renin secretion by about 30% in untreated uncomplicated hypertensive patients and by about 75% in those whose renin secretion had either been stimulated or suppressed by maintained diuretic or beta-adrenoreceptor-blockade therapy. 3. Indomethacin administration produced no net effect on blood pressure in untreated patients with uncomplicated hypertension but it blunted or reversed the antihypertensive effect of either diuretic or propranolol therapy. 4. Salt and water retention may be an important factor in the blood pressure-raising effect of indomethacin during diuretic or propranolol therapy: In addition, prostaglandin synthesis may be important in counteracting increased alpha-adrenergic tone, which may limit the blood pressure-lowering effect of beta-adrenoreceptor-blockade. 5. Because of these interactions and their pressor potential indomethacin should be used with caution when combined with either diuretics or beta-adrenoreceptor blockers.

Blood pressure, heart rate, plasma renin activity, plasma norepinephrine and plasma epinephrine were determined in 11 patients with essential hypertension at rest before and 15, 30, 45, and 60 minutes after an intravenous infusion of 0.12 mg./Kg. propranolol given over five minutes. After propranolol mean blood pressure was unchanged; heart rate decreased by 14 per cent within 15 minutes and showed no further changes. Plasma renin activity decreased progressively by 48 per cent 60 minutes after propranolol, whereas plasma norepinephrine and epinephrine were always higher after propranolol than control values. Increases in norepinephrine were statistically significant at 30, 45, and 60 minutes (respectively 49, 39, and 45 per cent, P less than 0.005 at least) and those of epinephrine even at 15 minutes (respectively 60, 82, 62, and 94 per cent P less than 0.01 for all). These results indicate that acute beta blockade with propranolol incudes increases in circulating plasma norepinephrine and epinephrine which might be consequent to rapidly induced hemodynamic changes. This augmented sympathetic activity might explain why propranolol, when acutely infused, does not decrease blood pressure despite effective cardiac and renin blockade.

In 79 patients with essential hypertension, treatment with propranolol hydrochloride and chlorthalidone together produced significantly greater falls in both systolic and diastolic blood pressures than were obtained with either drug alone. There were no differences between patients in the high, normal, and low renin subgroups in their responsiveness to this combination. Although plasma renin level during combined treatment was twice as high as it was in the untreated control, aldosterone excretion actually decreased. These divergent changes may have been influenced by the renin-raising and aldosterone-lowering effects of the marked hypokalemia observed during combined treatment. By comparison with patients whose blood pressures fell, treatment in nonresponding patients produced even greater body weight reductions and significantly higher renin and aldosterone values. It is possible that increased activity of the renin axis, triggered by excessive volume depletion and perhaps by changes in potassium balance, were responsible for sustaining the high levels of blood pressure in those patients failing to respond to treatment.