Multi-level Policy Coalitions An Interpretative Model Of Water Conflicts ιn The Americas

This article proposes an analytical approach to conflicts and policy-making related to urban water management based on multi-level policy coalitions. This is necessary to articulate four main issues. First, the repositioning of social and political struggles for access to water, along with policy variables. Second, the analysis of the effects of ecological transition, including climate change. Third, the reincorporation of these struggles and challenges in a multi-level approach. Finally, the enquiry into the apparent contradiction, in contemporary policymaking. The article proposes a definition of multi-level coalitions as collective preference systems that influence the content of policies (ideas/advocacy, decisions, policy tools) and their implementation, groups of actors that arise from engagement in policy issues. In the first section, the article presents the objectives of research on urban water management in the Americas, within the framework of which this analytical approach by multi-level coalitions is fashioned. In the second section, the article details four analytical issues. In the third section, it gives a definition of multi-level coalitions.19415317

Mõssbauer spectroscopy and dating by fission traces in provenience studies of archaeomaterials: obsidian artefacts

A obsidiana foi urna das matérias primas mais utilizadas na industria lírica pré-histórica; é encontrada em numerosos sitios arqueológicos de regiões vulcânicas, e também, em lugares às vezes distantes de sua origem. A busca de fontes naturais de onde provêm as obsidianas, encontradas em sitios arqueológicos, permite uma melhor compreensão dos sistemas de troca e/ou proveniência destes objetos. Por suas características físico-químicas e de afloramento, a obsidiana é urna das rochas preferidas para este tipo de estudo. Neste artigo, descrevemos brevemente dois métodos físicos atualmente utilizados em estudos de proveniência de obsidianas arqueológicas, a espectroscopia Mõssbauer e a datação por traços de fissão, onde são dados alguns exemplos de aplicação e comentadas as perspectivas oferecidas por esses métodosObsidian was one of the most widely used raw materials of the prehistoric lithic industry. It is present in many archaeological sites from volcanic provinces, but also in sites sometimes very far from any volcano. To look for the natural outcrop from where any particular archaeological obsidian was extracted is of prime importance to contribute to the knowledge of past trade networks and/or procurement strategies. Because of its physico-chemical and outcropping characteristics, obsidian is one of the preferred rocks for provenance studies. In this article, we describe briefly two physical methods presently used in obsidian sourcing, Mõssbauer spectroscopy and fission track dating. A few examples and the research perspectives offered by these approaches are commente

Time window-dependent effect of perinatal maternal protein restriction on insulin sensitivity and energy substrate oxidation in adult male offspring

Epidemiological and experimental evidence suggests that a suboptimal environment during perinatal life programs offspring susceptibility to the development of metabolic syndrome and Type 2 diabetes. We hypothesized that the lasting impact of perinatal protein deprivation on mitochondrial fuel oxidation and insulin sensitivity would depend on the time window of exposure. To improve our understanding of underlying mechanisms, an integrative approach was used, combining the assessment of insulin sensitivity and untargeted mass spectrometry-based metabolomics in the offspring. A hyperinsulinemic-euglycemic clamp was performed in adult male rats born from dams fed a low-protein diet during gestation and/or lactation, and subsequently exposed to a Western diet (WD) for 10 wk. Metabolomics was combined with targeted acylcarnitine profiling and analysis of liver gene expression to identify markers of adaptation to WD that influence the phenotype outcome evaluated by body composition analysis. At adulthood, offspring of protein-restricted dams had impaired insulin secretion when fed a standard diet. Moreover, rats who demonstrated catch-up growth at weaning displayed higher gluconeogenesis and branched-chain amino acid catabolism, and lower fatty acid β-oxidation compared with control rats. Postweaning exposure of intrauterine growth restriction-born rats to a WD exacerbated incomplete fatty acid β-oxidation and excess fat deposition. Control offspring nursed by protein-restricted mothers showed peculiar low-fat accretion through adulthood and preserved insulin sensitivity even after WD-exposure. Altogether, our findings suggest a testable hypothesis about how maternal diet might influence metabolic outcomes (insulin sensitivity) in the next generation such as mitochondrial overload and/or substrate oxidation inflexibility dependent on the time window of perinatal dietary manipulation

Performance improvement of the multicell cavity prototype for proton Linac projects

The CEA-Saclay / IPN-Orsay collaboration allowed to manufacture a multicell superconducting RF cavity prototype for proton linac. Since the first experimental results [1], obtained in a vertical cryostat and the horizontal cryostat CryHoLab, the accelerating field Eacc has been recently increased up to 19 MV/m with a quality factor Q0 = 9.109 and a limitation by quench. However some improvements are still needed, in particular to suppress the field emission above 16 MV/m

Luminescence characteristics of quartz from Brazilian sediments and constraints for OSL dating

This study analyzes the optically stimulated luminescence (OSL) characteristics of quartz grains from fluvial, eolian and shallow marine sands of northeastern and southeastern Brazil, with especial focus on the applicability of the single-aliquot regenerative dose (SAR) dating protocol. All analyzed Brazilian sediments presented relatively high OSL sensitivity and good behavior regarding their luminescence characteristics relevant for radiation dose estimation. However, some samples from the Lençóis Maranhenses region in northeastern Brazil showed inadequate OSL sensitivity correction, hampering the implementation of the SAR protocol and their ability to behave as a natural dosimeter. While the shallow marine and eolian samples showed a narrow and reliable dose distribution, the fluvial sample had a wide dose distribution, suggesting incomplete bleaching and natural doses estimates dependent on age models

Fission track dating workshop

International audienc