Search results for "34"

Formation of secondary carbonates and native sulphur in sulphate-rich Messinian strata, Sicily

2010

Abstract Microbially formed authigenic carbonates accompanied by native sulphur are present in the ‘Calcare Solfifero’ below a thick succession of gypsum deposited during the Messinian salinity crisis in Sicily. We sampled these carbonates and associated sulphur in five former sulphur mines to subject them to a detailed petrographic and geochemical study in order to explore their different modes of formation. Native sulphur formed in conjunction with microbial sulphate reduction, which is reflected in its depletion in 34S (δ34S values as low as − 2‰ vs. V-CDT) and an enrichment of 34S in the residual sulphate (δ34S values as high as + 61‰). The oxidation of organic matter by sulphate reduct…

Agroecological engineering

2015

Earth has recently entered the new era of the Anthropocene, during which the rise of human activities are impacting for the first time ecosystems and climate on the global scale. Since the 1960s the green revolution has improved food production in quantity using industrially-designed agriculture, which has led to global pollution by pesticides and losses of food quality, biodiversity and soil carbon. As a consequence there is a need to implement agroecological practices in order to produce food safely and in a sustainable way. This virtual issue presents principles and applications of agroecological engineering, exemplified in 19 selected review articles from the journal Agronomy for Sustai…

Los usos sociales de la ciencia: tecnologías convergentes y democratización del conocimiento

2009

La globalización neoliberal de las últimas décadas ha traído aparejadas inmensas transforma- ciones económicas, políticas y sociales. La reorganización del sistema capitalista que surge de este periodo se ha concretado en el incremento de la vulnerabilidad y las desigualdades sociales, dando lugar a la emergencia de la llamada 'nueva cuestión social'. El planteamiento que aquí se sigue investiga el papel que el conocimiento científico y la tecnociencia juegan en el capitalismo cognitivo como intensificadores de las formas de desigualdad. Atender esto resulta necesario para entender y completar la comprensión de las diferentes dimensiones de las desigualdades económicas, sociales y culturale…

Co-determination and Merger Incentives from Transfers of Wealth: Firm Owners vs. Workers

2010

When workers can capture rents from their influence on corporate decisions, mergers can become a device to generate transfers of wealth. This paper examines the merger incentives from these transfers of wealth. It is found that worker influence increases merger profitability, in line with the owners’ incentive to use mergers to reduce the rents captured by workers. In contrast, the workers’ merger incentives are shown to be decreasing in their own degree of influence on the merger decision, in line with the view according to which workers can be used by incumbent managers as a defensive instrument in acquisitions.

EU income stabilization tool: potential impacts, financial sustainability and farmer’s risk aversion

2021

AbstractThe Income Stabilization Tool, a risk management scheme introduced within the Common Agricultural Policy (CAP) 2014–2020, could help European Union farmers manage the income risks they face. This study assesses the potential impact of implementing this tool through the maximum level of contribution to the fund which determines an indifference to participate in the fund and its financial sustainability. The study relies on an expected utility approach and assesses the variability of loss ratios over time using a sample of Italian hazelnut farms as a case study. The participation depends on the level of farmers' contributions and their degree of risk aversion. However, the CAP public …

Entretien : pour une intégration des datadéontologues dans les équipes communication

2018

Conversation autour de l’éthique en pratique : une carrière de communicante sous le signe d’une réflexion et de préoccupations éthiques

2017

Ex vivo expansion of umbilical cord blood (UCB) CD34+ cells alters the expression and function of α4β1 and α5β1 integrins

2001

We have investigated the influence of ex vivo expansion of human CD34+ cord blood cells on the expression and function of adhesion molecules involved in the homing and engraftment of haematopoietic progenitors. Ex vivo expansion of umbilical cord blood CD34+ cells for 6 d in the presence of interleukin 3 (IL-3), IL-6 and stem cell factor (SCF) or IL-11, SCF and Flt-3L resulted in increased expression of α4, α5, β1, αΜM and β2 integrins. However, a significant decrease in the adhesion of progenitor cells to fibronectin was observed after the ex vivo culture (adhesion of granulocyte-macrophage colony-forming units (CFU-GM) was 22 ± 4% in fresh cells versus 5 ± 2% and 2 ± 2% in each combinatio…

On critical behaviour in systems of Hamiltonian partial differential equations

2013

Abstract We study the critical behaviour of solutions to weakly dispersive Hamiltonian systems considered as perturbations of elliptic and hyperbolic systems of hydrodynamic type with two components. We argue that near the critical point of gradient catastrophe of the dispersionless system, the solutions to a suitable initial value problem for the perturbed equations are approximately described by particular solutions to the Painlevé-I (P $$_I$$ I ) equation or its fourth-order analogue P $$_I^2$$ I 2 . As concrete examples, we discuss nonlinear Schrödinger equations in the semiclassical limit. A numerical study of these cases provides strong evidence in support of the conjecture.

(Supplement Table S2) Results of 230Th/U-dating

2016

We compared the suitability of two skeletal materials of the Atlantic brain coral Diploria strigosa for 230Th/U-dating: the commonly used bulk material comprising all skeletal elements and the denser theca wall material. Eight fossil corals of presumably Last Interglacial age from Bonaire, southern Caribbean Sea, were investigated, and several sub-samples were dated from each coral. For four corals, both the ages and the activity ratios of the bulk material and theca wall agree within uncertainty. Three corals show significantly older ages for their bulk material than for their theca wall material as well as substantially elevated 232Th content and (230Th/238U) ratios. The bulk material sam…