Search results for "Arid"

Efficient boron removal by using mesoporous matrices grafted with saccharides.

2004

Highly efficient boron removal from water was achieved by using mesoporous silica materials functionalised with saccharides. Beltran Porter, Daniel, Daniel.Beltran@uv.es ; Amoros del Toro, Pedro Jose, Pedro.Amoros@uv.es

Thermal restraint of a bacterial exopolysaccharide of shallow vent origin

2018

This is the post-print version of the following article: "Thermal restraint of a bacterial exopolysaccharide of shallow vent origin", which has been published in final form at https://www.sciencedirect.com/science/article/pii/S0141813018308250?via%3Dihub; International audience; To dynamically characterize the thermal properties of the fructose-rich exopolysaccharide (EPS1-T14), produced by themarine thermophilic Bacillus licheniformis T14, the Attenuated Total Reflectance Fourier Transform Infra-Redspectroscopy was coupled to variable temperature ranging from ambient to 80 °C.The spectra were analyzed by the following innovative mathematical tools: i) non-ideal spectral deviation, ii) OHst…

Preparation and Characterization of Gold Nanorods Coated with Gellan Gum and Lipoic Acid

2020

Gold nanorods (AuNRs) can combine therapeutic hyperthermia with diagnostic features, representing a smart choice to address personalized cancer treatments. In this regard, a crucial quest is the selection of the right biocompatible coating agent able to stabilize them in the physiological environment, further endowing the possibility to load bioactive molecules and/or targeting moieties. Therefore, AuNRs optical properties can be successfully merged with advantageous materials features to obtain selective photothermal therapy (PTT) systems. Here, the natural materials lipoic acid (LA) and the polysaccharide gellan gum (GG) were chosen to prepare three types of stabilized gold nanorods, usin…

Polysaccharide remains in Maya mural paintings: is it an evidence of the use of plant gums as binding medium of pigments and additive in the mortar?

2020

A number of monosaccharides characteristic of plant gums were found in paint layers and preparation layers of samples of Maya mural paintings of 10 archaeological sites located in Campeche and Yucatan regions. This finding opens the question about the deliberate use of these organic polymers as additives for improving workability and mechanical properties in the preparation layer mortar and conferring cohesion to the pigments in the paint layer. The study performed by GC-MS has confirmed the presence, in significant amounts, of a series of monosaccharides, being glucose and mannose between the most abundantly found. Nevertheless, the low amount present in most of the samples hindered the qu…

COLLECTIVE DELIBERATION: A CONTEMPORARY CONTRIBUTION OF BRAZILIAN BIOETHICS TO THE SUS' (UNIFIELD HEALTH SERVICE) PRACTICES

2017

Resumo Este ensaio teve por objetivo analisar a necessidade de nova excelência profissional pautada na deliberação coletiva, debatendo a ética aplicada às questões de saúde nas experiências de Brasil e Espanha. O funcionamento prático dos comitês de bioética na Espanha avança na constituição do método deliberativo como participação coletiva na decisão profissional, discutindo a importância da democracia deliberativa para a construção de nova civilidade ética. No Brasil, após as primeiras décadas de construção do Sistema Único de Saúde, amplia-se o leque de participação dos profissionais, primeiramente nos conselhos de saúde e, com a resolução CNS n. 196/96, também nos comitês de ética em pe…

Aridity index, soil erosion and climate drive no-till ecosystem services trade-off in Mediterranean arable land

2021

Abstract Despite the relevant literature on the advantages of no-till (NT) management, the world area under NT is only 10% of the arable land, probably due to several limiting factors as climate, soil types, farming systems and yield. Soil conservation practices and particularly NT soil management are able to provide many ecosystem services (ESs). This paper suggests a framework to determine the area distribution of soil erosion control and food security ESs trade-offs furnished by NT, starting from the potential soil erosion and aridity index maps. The interaction between the potential soil erosion and the aridity index showed that different trade-offs and synergies of multiple ESs may occ…

2018

Abstract. The 4.2 ka BP event is defined as a phase of environmental stress characterized by severe and prolonged drought of global extent. The event is recorded from the North Atlantic through Europe to Asia and has led scientists to evoke a 300-year global mega-drought. For the Mediterranean and the Near East, this abrupt climate episode radically altered precipitation, with an estimated 30 %–50 % drop in rainfall in the eastern basin. While many studies have highlighted similar trends in the northern Mediterranean (from Spain to Turkey and the northern Levant), data from northern Africa and the central-southern Levant are more nuanced, suggesting a weaker imprint of this climate shift on…

Holocene environmental and climatic changes at Gorgo Basso, a coastal lake in southern Sicily, Italy

2009

Abstract We used a new sedimentary record to reconstruct the Holocene vegetation and fire history of Gorgo Basso, a coastal lake in south-western Sicily (Italy). Pollen and charcoal data suggest a fire-prone open grassland near the site until ca 10,000 cal yr BP (8050 cal BC), when Pistacia shrubland expanded and fire activity declined, probably in response to increased moisture availability. Evergreen Olea europaea woods expanded ca 8400 to decline abruptly at 8200 cal yr BP, when climatic conditions became drier at other sites in the Mediterranean region. Around 7000 cal yr BP evergreen broadleaved forests ( Quercus ilex , Quercus suber and O. europaea ) expanded at the cost of open commu…

Sensitivity of extreme rainfall to temperature in semi-arid Mediterranean regions

2019

Abstract Warmer air has the potential to hold more water vapour and, therefore, to provide more water to rainfall events. Studying the relationship between rainfall and temperature represents an emerging issue in hydrology and meteorology, since it can be considered fundamental for evaluating the effects of global warming on future precipitation. Various approaches have been tested across different parts of the world, in many cases observing an intensification of extreme precipitation at higher temperatures consistent with the well-known thermodynamic Clausius-Clapeyron relation (CC-scaling rate of 6–7%°C−1). However, at different locations for hourly time-scales, the temperature-extreme ra…

Start of the dry season as a main determinant of inter-annual Mediterranean forest production variations

2014

Abstract Recent investigations have highlighted the dependence of Mediterranean forest production on spring rainfall. The current work introduces the concept of the start of the dry season (SDS) and performs a three-step analysis to determine the effect of SDS on Mediterranean forest production. Seven forest zones of Tuscany (Central Italy), which present differently pronounced Mediterranean features, are considered. First, a statistical analysis investigates the influence of spring water budget on forest Normalized Difference Vegetation Index (NDVI) inter-annual variations during July–August. The analysis is then extended to assess the impact of inter-annual SDS variability on forest gross…