Antimicrobial activity of nine extracts of sechium edule (Jacq) swartz

The antimicrobial properties of Sechium edule (Jacq) Swartz alcoholic extracts obtained according to the Farmacopea Argentina (6th edn) were tested against bacteria of clinical relevance as nosocomial pathogens. To evaluate antibacterial activity, the disc diffusion assay was carried out with several gram-positive bacteria (Enterococcus faecalis, Staphylococcus aureus, coagulase-negative staphylococci, Streptococcus pyogenes, Streptococcus agalactiae, Staphylococcus aureus ATCC 29213, Enterococcus faecalis ATCC 29212). This assay was suitable for the screening of a large number of extracts at one time. All ethanolic extracts showed activity against gram-positive bacteria. Minimal inhibitory concentration (MIC) values were determined with a microdilution assay. The highest activity was obtained with the 80% aqueous-ethanolic leaf extract (MIC values of 4.16/8.32 mg/ml against staphylococci and enterococci) and with the 96% ethanolic seed extract (MIC values of 8.32/16.64 mg/ml and /8.32 mg/ml against staphylococci and enterococci, respectively). The results indicate that both fluid extract and tincture have very good antimicrobial efficacy against all strains of multiresistant staphylococci and enterococci. In this study the minimal bactericidal concentration (MBC) values were identical to the MIC values or twofold higher than the corresponding MIC. This may indicate a bactericidal effect. Stored extracts have similar anti-staphylococcal and anti-enterococcal activity to recently obtained extracts. The results obtained might be considered sufficient to warrant further studies aimed at isolation and identification of the active principle.Fil: Ordoñez, Alicia Lucia. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; ArgentinaFil: Gómez, José D.. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; ArgentinaFil: Cudmani, Norma Mercedes. Gobierno de la Provincia de Tucumán. Ministerio de Salud. Sistema Provincial de Salud. Hospital de Clínicas "Dr. Nicolás Avellaneda"; Argentina. Gobierno de la Provincia de Tucumán. Ministerio de Salud. Departamento Bioquímico; ArgentinaFil: Vattuone, Marta Amelia. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Estudios Vegetales; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; ArgentinaFil: Isla, Maria Ines. Universidad Nacional de Tucumán. Instituto de Bioprospección y Fisiología Vegetal. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet Noa Sur. Instituto de Bioprospección y Fisiología Vegetal; Argentina. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Estudios Vegetales; Argentin

A simple methodology to estimate plant volume in nitrous oxide emission studies

Closed-chamber methodology is widely used for the estimation of greenhouse gas (GHG) emissions in agricultural systems. The volume displaced by plants inside chambers influences GHG flux estimation, although generally it is not discounted from chamber headspace in the calculation. A novel image analysis–based procedure is proposed to estimate plant volume and to assess its impact on nitrous oxide (N2O) flux estimations in a wheat (Triticum aestivum L. ‘Rimbaud’) crop. A maximum of 2.2% of the 13-L chambers was displaced by plants, leading to a systematic 0.9% overestimation in cumulative N2O emissions if plant volume was not considered. Thus, plant canopy volume should be taken into account for improving the accuracy of emissions

Utility of stabilized nitrogen fertilizers to reduce nitrate leaching under optimal management practices

Background: The inadequate application of nitrogen (N) to crops has increased the reactive N in the atmosphere and in the surface and ground waters. Stabilized N-fertilizers with nitrification (NI) and urease (UI) inhibitors have been proposed to reduce these environmental problems without affecting or even increasing crop productivity. Aim: The objective of this study was to evaluate, in a maize–maize–wheat rotation, if the use of the NI 3, 4-dimethylpyrazole phosphate (DMPP) and the UIs N-(n-butyl) thiophosphoric triamide (NBPT) and monocarbamide dihydrogen sulfate (MCDHS) reduces N leaching without compromising yield under optimal management of N and water. Methods: The experiment was conducted in 24 drainage lysimeters with two soil types with contrasting water holding capacity under Mediterranean irrigated conditions. The fertilizer treatments were urea, urea with DMPP, urea with NBPT, and urea with MCDHS. For the maize crop, conventional fertilizer application was split into 6- and 13-leaf stages, whereas stabilized fertilizers were applied as a single application at the 6-leaf stage. All fertilizer treatments were applied at late tillering in the wheat crop. Results: The soil mineral N was measured at the beginning and the end of each crop season, but no differences were found among fertilizer treatments. Differences in the volume of water drained or the cumulative mass of nitrate depending on the fertilizer were not significant (three-year treatment average of 200 L m-2 and 22 kg N ha-1 in the Deep soil, and 334 L m-2 and 40 kg N ha-1 in the Shallow type, respectively). No consistent significant differences were found in agronomic parameters (chlorophyll measurements, yield, and total N uptake) between the fertilizer treatments. Conclusion: Based on the results, the use of stabilized N-fertilizer could be recommended to reduce the number of N applications in maize without compromising grain yield but with no advantages to reduce nitrate-leaching losses if N rates are managed properly under efficient irrigation management practices

Agronomic and environmental implications of substituting pig slurry for synthetic nitrogen in mediterranean wheat systems

Using slurries as fertilizers is a promising strategy for the reuse of nutrients and striving towards a circular economy. This study aims to assess the agronomic productivity and the environmental effects on Mediterranean sprinkler-irrigated wheat during three consecutive years of (1) the use of pig slurry (PS) as a substitute for a synthetic fertilizer (urea, U) and (2) the addition of a urease inhibitor (monocarbamide dihydrogen sulfate, MCDHS) to pig slurry (PSI). A nitrogen (N) target rate of 120 kg NH4+-N ha-1 as U, PS, or PSI (main factor) was applied at tillering, and it was supplemented with N application at stem elongation (secondary factor). Grain yield, nitrogen use efficiency indexes, and nitrous oxide emissions were not significantly affected by the N source, U, or PS; in contrast to grain protein that was affected by the N source (lower protein content in PS). The higher unaccounted N from soil balance in PS compared to U fertilization could be associated with higher ammonia volatilization, although additional studies should confirm this hypothesis. Our study suggests that, under the considered cropping conditions, PS does not affect productivity or N2O losses compared to U. The addition of MCDHS to pig slurry did not display agronomic or environmental benefits under the evaluated agro-environmental conditions

How, when, and why is social class linked to mental health and wellbeing? A systematic meta-review.

Meta-reviews synthesising research on social class and mental health and wellbeing are currently limited and focused on specific facets of social class (e.g., social capital) or mental health and wellbeing (e.g., mental health disorders), and none sought to identify mechanisms in this relationship. The present meta-review sought to (1) assess the overall relationship between social class and mental health and wellbeing, (2) determine the mechanisms that act in this relationship, and (3) evaluate the strength of evidence available. The protocol was prospectively registered on PROSPERO (CRD42021214731). We systematically searched twelve databases in September 2022 and identified 149 eligible reviews from 38,257 records screened. Quality of evidence was assessed with the JBI levels of evidence and risk of bias with the ROBIS tool. A large but low-quality evidence base points to class-based inequalities in mental health and wellbeing, with the strongest available evidence linking lower social positions to an increased risk of depression. In terms of different facets of stratification, the best available evidence suggests that deprivation (e.g., poverty), socioeconomic status, income, and subjective social status are consequential for individuals' mental health and wellbeing. However, high-quality evidence for the roles of education, occupation, other economic resources (e.g., wealth), and social capital is currently limited. Most reviews employed individual-level measures (e.g., income), as opposed to interpersonal- (e.g., social capital) or community-level (e.g., neighbourhood deprivation) measures. Considering mechanisms, we found some evidence for mediation via subjective social status, sense of control, and experiences of stress and trauma. There was also some evidence that higher socioeconomic status can provide a buffer for neighbourhood deprivation, lower social capital, and lower subjective social status. Future research employing experimental or quasi-experimental methods, and systematic reviews with a low risk of bias, are necessary to advance this area of research. [Abstract copyright: Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.

Formulation and conservation of a pharmaceutical form with leaf extracts from Acacia aroma Gill. ex Hook et Arn

Leaf fluid extracts of Acacia aroma GILL. ex Hook et Arn showed antibacterial activity against antibiotic multi-resistant bacteria isolated from clinical samples, antioxidant and antiinflammatory activities. Toxicological studies carried out on Artemia salina and Allium cepa attested none toxicity potential. The aim of this work was to elaborate a formulation of topical antibacterial hydrogel with Carbopol acrylic acid polymer containing an A. aroma fluid extract in order to compare with a hydrogel containing commercial antibiotic. The optimal extract concentration in this formulation was determined according to the values of minimal inhibitory concentration and minimal bactericidal concentration for Staphylococcus aureus, methicillin-resistant (F7) and Pseudomonas aeruginosa (F352) . Physical, chemical, rheological and microbiological stability was observed at least during one year. The hydrogel containing Acacia leaves fluid extract shows remarkable antibacterial effect with a broad-spectrum efficacy against Gram positive and Gram negative bacteria at low concentration.Fil: Arias, M. E.. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; ArgentinaFil: Gomez, J. D.. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; ArgentinaFil: Vatuone, M. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia; ArgentinaFil: Isla, Maria Ines. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Química del Noroeste. Universidad Nacional de Tucumán. Facultad de Bioquímica, Química y Farmacia. Instituto de Química del Noroeste; Argentin

One size fits ball: Macrocyclic hosts for fullerenes with micromolar affinity

Date du colloque : 25/03/2012International audienc

Echolocation detections and digital video surveys provide reliable estimates of the relative density of harbour porpoises

Acknowledgements We would like to thank Erik Rexstad and Rob Williams for useful reviews of this manuscript. The collection of visual and acoustic data was funded by the UK Department of Energy & Climate Change, the Scottish Government, Collaborative Offshore Wind Research into the Environment (COWRIE) and Oil & Gas UK. Digital aerial surveys were funded by Moray Offshore Renewables Ltd and additional funding for analysis of the combined datasets was provided by Marine Scotland. Collaboration between the University of Aberdeen and Marine Scotland was supported by MarCRF. We thank colleagues at the University of Aberdeen, Moray First Marine, NERI, Hi-Def Aerial Surveying Ltd and Ravenair for essential support in the field, particularly Tim Barton, Bill Ruck, Rasmus Nielson and Dave Rutter. Thanks also to Andy Webb, David Borchers, Len Thomas, Kelly McLeod, David L. Miller, Dinara Sadykova and Thomas Cornulier for advice on survey design and statistical approache. Data Accessibility Data are available from the Dryad Digital Repository: http://dx.doi.org/10.5061/dryad.cf04gPeer reviewedPublisher PD

Broad-Scale Responses of Harbor Porpoises to Pile-Driving and Vessel Activities During Offshore Windfarm Construction

This study was partly funded by Beatrice Offshore Wind Ltd. and Moray Offshore Wind Farm (East) Ltd. using equipment previously purchased by UK Department of Energy & Climate Change, Scottish Government, Oil and Gas UK, COWRIE and Moray Offshore Renewables Ltd.. P.T. and I.G. were core funded by University of Aberdeen. A.B. was core funded by the collaboration between University of Aberdeen and Marine Scotland Science through the MarCRF PhD studentship. N.M. was core funded by Centre for Environment, Fisheries and Aquaculture Science.Peer reviewedPublisher PD