Search results for "USA"
showing 10 items of 3178 documents
Segmentando el mercado de internautas atendiendo a su nivel de afinidad: (I)fuerte, (II)medio y (III)débil
2017
Esta investigación pretende confrontar el Marketing con Causa con el Marketing de Afinidad. Para ello se descompone la audiencia de una campaña de Marketing con Causa viral en segmentos de internautas con distinto nivel de afinidad: i) fuerte (con experiencia previa de marca y de causa); ii) medio (con experiencia previa o de marca o de causa); iii) débil (sin experiencia previa ni de marca ni de causa). El objetivo es justificar la utilidad de este criterio como vía para optimizar el resultado de la comunicación segmentada. Con dicho fin, se ha estudiado un caso real planteado de forma experimental midiendo las actitudes de una muestra de 276 internautas antes y después de visualizar un sp…
Involvement of enniatins-induced cytotoxicity in human HepG2 cells.
2012
Enniatins (ENNs) are mycotoxins found in Fusarium fungi and they appear in nature as mixtures of cyclic depsipeptides. The ability to form ionophores in the cell membrane is related to their cytotoxicity. Changes in ion distribution between inner and outer phases of the mitochondria affect to their metabolism, proton gradient, and chemiosmotic coupling, so a mitochondrial toxicity analysis of enniatins is highly recommended because they host the homeostasis required for cellular survival. Two ENNs, ENN A and ENN B on hepatocarcinoma cells (HepG2) at 1.5 and 3 μM and three exposure times (24, 48 and 72 h) were studied. Flow cytometry was used to examine their effects on cell proliferation, t…
Identification of Patulin from Penicillium coprobium as a Toxin for Enteric Neurons
2019
The identification and characterization of fungal commensals of the human gut (the mycobiota) is ongoing, and the effects of their various secondary metabolites on the health and disease of the host is a matter of current research. While the neurons of the central nervous system might be affected indirectly by compounds from gut microorganisms, the largest peripheral neuronal network (the enteric nervous system) is located within the gut and is exposed directly to such metabolites. We analyzed 320 fungal extracts and their effect on the viability of a human neuronal cell line (SH-SY5Y), as well as their effects on the viability and functionality of the most effective compound on primary ent…
DNA barcoding reveals different cestode helminth species in northern European marine and freshwater ringed seals
2021
Three subspecies of the ringed seal (Pusa hispida) are found in northeastern Europe: P. h. botnica in the Baltic Sea, P. h saimensis in Lake Saimaa in Finland, and P. h. ladogensis in Lake Ladoga in Russia. We investigated the poorly-known cestode helminth communities of these closely related but ecologically divergent subspecies using COI barcode data. Our results show that, while cestodes from the Baltic Sea represent Schistocephalus solidus, all worms from the two lakes are identified as Ligula intestinalis, a species that has previously not been reported from seals. The observed shift in cestode communities appears to be driven by differential availability of intermediate fish host spec…
Sécheresse et inconfort thermique : Le changement climatique se fait ressentir
2023
Biodiversité, rendements agricoles, élevage, pêche… Rien n’est épargné par le changement climatique. Zoom sur deux effets en passe de devenir tristement familiers.
ChemInform Abstract: Supported Proline and Proline-Derivatives as Recyclable Organocatalysts
2008
In the last eight years, L-proline and L-proline derivatives, such as substituted prolinamides or pyrrolidines, have been successfully used as organocatalysts in several reactions. In this critical review we summarize the immobilization procedures of such organocatalysts highlighting their application, recoverability and reusability (86 references).
Walking Children Through a Minefield: How Professionals Experience Exploring Adverse Childhood Experiences
2017
Understanding the challenges of professionals in addressing child adversity is key to improving the detection, protection, and care of exposed children. We aimed to synthesize findings from qualitative studies of professionals’ lived experience of addressing child adversity. Through a systematic search, we identified eight qualitative studies and synthesized them using metaethnography. We generated three themes, “feeling inadequate,” “fear of making it worse,” and “facing evil,” and one overarching metaphor, “walking children through a minefield.” The professionals felt that they lacked the means necessary to explore child adversity, that they were apprehensive of worsening the child’s situ…
Sustainable Development and Energy Policy: Actual CO2 Emissions in the European Union in the Years 1997–2017, Considering Trade with China and the USA
2020
One of the ways of implementing the concept of sustainable development by the European Union is their energy policy. Among the three main objectives in its energy policy is a reduction in greenhouse gases (mainly CO2) emissions to at least 20% below 1990 levels by 2020. This study aims to assess the impact of international trade on actual CO2 emission in the EU, China and the USA for the period 1997–2017. For this aim, the Actual-Open CO2 emissions were calculated, taking into account the transfer of CO2 in exported products and services from China and the USA to the EU and vice versa. It is concluded that the actual CO2 emissions in China, the USA, and the EU differed from the traditionall…
Volatile components from flower-heads of Centaurea nicaeensis All., C. parlatoris Helder and C. solstitialis L. ssp. schouwii (DC.) Dostál growing wi…
2008
The volatile constituents of the flowerheads of Centaurea nicaeensis All., C. parlatoris Helder and C. solstitialis L. ssp. schouwii (DC.) Dostal were extracted by hydrodistillation and analysed by GC and GC-MS. Altogether 113 components were identified. Fatty acids and hydrocarbons were the most abundant components in the oils. Caryophyllene and caryophyllene oxide were the main compounds of the sesquiterpene fraction. The study on the biological activity of the oils shows no significant activity.
A rapid and sensitive method for the control of selected regulated and emerging mycotoxins in beer
2018
A fast method using automated online solid-phase extraction (SPE) coupled to liquid-chromatography/high resolution mass spectrometric (LC-HRMS) detection for the determination of 12 mycotoxins in beer was developed and fully validated according to the performance criteria set in the European Union (EU) guidelines. Mycotoxin detection was achieved by full-scan HRMS with electrospray ionisation in positive ion mode within 13 min. No significant matrix interferences were observed. The lowest limits of detection (LODs) were achieved for emerging mycotoxins (beauvericin and enniatins) and ochratoxin A at levels between 0.01 and 0.02 μg/l, while the overall LODs were in the range of 0.01-0.30 μg…