Search results for "MACRO"

Response of soil bacteria to Hg (II) in relation to soil characteristics and cell location

2006

The response of indigenous bacterial communities to the addition of inorganic mercury (50 μM of Hg(II)) was compared over a 30 day period in four soils of contrasting properties. Hg(II) impact was estimated by following population dynamics of viable heterotrophic bacteria (VH) and mercury resistant bacteria (HgR) by indirect enumeration in unfractionated soil and in the inner and outer parts of soil aggregates obtained by successive washings. Numbers of VH bacteria in unfractionated soils were not affected by mercury in any of the studied soils, whereas an increase in resistant bacteria was observed in all of them. The lag phase before the increase of HgR bacteria and the magnitude of the e…

GrassPlot v. 2.00 : first update on the database of multi-scale plant diversity in Palaearctic grasslands

2019

Abstract: GrassPlot is a collaborative vegetation-plot database organised by the Eurasian Dry Grassland Group (EDGG) and listed in the Global Index of Vegetation-Plot Databases (GIVD ID EU-00-003). Following a previous Long Database Report (Dengler et al. 2018, Phyto- coenologia 48, 331–347), we provide here the first update on content and functionality of GrassPlot. The current version (GrassPlot v. 2.00) contains a total of 190,673 plots of different grain sizes across 28,171 independent plots, with 4,654 nested-plot series including at least four grain sizes. The database has improved its content as well as its functionality, including addition and harmonization of header data (land use,…

1972

The present paper demonstrates theoretically as well as experimentally, that the gravitational field of the earth produces very pronounced changes in the equilibrium concentration of dissolved macromolecules with height, under near critical conditions. Thus it could be observed for the system polystyrene/cyclohexane that the equilibrium concentration at the bottom of a tube is approximately three times that at a height of 10 cm, under such conditions. In the case of polymolecular samples the sedimentation is associated with a corresponding fractionation. Die vorliegende Arbeit zeigt sowohl theoretisch als auch experimentell, das das Schwerefeld der Erde unter annahernd kritischen Bedingunge…

New approach for synthesis of poly(ethylglyoxylate) using Maghnite-H + , an Algerian proton exchanged montmorillonite clay, as an eco-catalyst

2017

International audience; In this works, we have explored a new method for a green synthesis of poly(ethylglyoxylate) (PEtG). This method consists on using a montmorillonite clay called Maghnite-H+ as an eco-catalyst to replace triethylamine which is toxic. Cationic polymerization experiments are performed in bulk conditions at three temperatures (-40 degrees C, 25 degrees C, 80 degrees C) and in THF solutions at room temperature (25 degrees C). At 25 degrees C, an optimum ratio of 5 wt% of catalyst leads to molar masses up to 22000 g/mol in THF solutions. Polymerizations in bulk conditions lead to slightly lower masses than experiments conducted in THF solutions. However, bulk polymerization…

Quantifying Excess Deaths Related to Heatwaves under Climate Change Scenarios: A multicountry time series modelling study

2018

Background: Heatwaves are a critical public health problem. There will be an increase in the frequency and severity of heatwaves under changing climate. However, evidence about the impacts of climate change on heatwave-related mortality at a global scale is limited. Methods and findings: We collected historical daily time series of mean temperature and mortality for all causes or nonexternal causes, in periods ranging from January 1, 1984, to December 31, 2015, in 412 communities within 20 countries/regions. We estimated heatwave–mortality associations through a two-stage time series design. Current and future daily mean temperature series were projected under four scenarios of greenhouse g…

Economic feasibility study for intensive and extensive wastewater treatment considering greenhouse gases emissions

2013

Economic feasibility assessments represent a key issue for selecting which wastewater treatment processes should be implemented. The few applications that exist focus on the positive economic value of externalities, overlooking the existence of negative externalities. However, wastewater treatment plants (WWTPs) consume a significant amount of energy, contributing to climate change. In this context, as a pioneering approach, greenhouse gas emissions (GHG) have been incorporated as a negative externality of wastewater treatment. Within this framework, this study aims to compare the economic feasibility of five technologies, both intensive and extensive, for small communities. The results sho…

Ab initio determination of the electron affinities of DNA and RNA nucleobases

2008

High-level quantum-chemical ab initio coupled-cluster and multiconfigurational perturbation methods have been used to compute the vertical and adiabatic electron affinities of the five canonical DNA and RNA nucleobases: uracil, thymine, cytosine, adenine, and guanine. The present results aim for the accurate determination of the intrinsic electron acceptor properties of the isolated nucleic acid bases as described by their electron affinities, establishing an overall set of theoretical reference values at a level not reported before and helping to rule out less reliable theoretical and experimental data and to calibrate theoretical strategies. Daniel.Roca@uv.es Manuela.Merchan@uv.es Luis.Se…

In vitro synthesis of factor B of the alternative pathway of complement activation by mouse peritoneal macrophages

1976

Factor B of the alternative pathway of complement activation was shown to be synthesized and secreted by unstimulated mouse peritoneal macrophages. The activity of B in the culture supernatants from macrophage monolayers was detected by consumption of C3 in reaction mixtures containing supernatant and guinea pig factors C3, D and insoluble C3b. Using a monospecific antiserum, factor B in concentrated culture supernatants was shown by immunodiffusion and immunoelectrophoresis to be identical to factor B in mouse plasma and to form a characteristic complex with cobra venom factor in the presence of D. A steady rate of factor B secretion was observed for 4 days providing the medium was changed…

Influence of Macrophage Activation on the Synthesis of Complement Components C2, C3, C4

1982

Macrophages are a major site of complement synthesis. In the guinea pig production of complement components C1, C2, C4, C3, D, B, and P by peritoneal macrophages has been demonstrated (reviewed in Ref. 1). Whereas marked differences exist in biological activity between resident, elicited and activated macrophages (2), we investigated whether this holds true for the synthesis and secretion of complement components C2, C3, and C4.

Standard international recommendations for gestational weight gain: suitability for our population

2020

Background: gestational weight gain (GWG) is one of the most commonly used indicators in prenatal care, and probably the most influential factor in perinatal outcomes. Objective: to determine the extent to which the GWG of pregnant women from the Ribera Health Department (Valencia) meets GWG international standards as recommended by the U.S. Institute of Medicine (IOM). Methods: a retrospective observational study of a sample of 4,361 women who gave birth at Hospital Universitario de la Ribera between January 1, 2010 and December 31, 2015. Pregnant women were classified according to GWG international recommendations: adequate weight gain, above and below. Results: a higher GWG increases the…