The role of land and water for trade and food production in Latin America: Environmental trade-offs of agricultural intensification versus extensification

One of humanity’s major challenges of the 21st century will be meeting future food demands on an increasingly resource constrained-planet. Global food production will have to rise by 70 percent between 2000 and 2050 to meet effective demand which poses major challenges to food production systems. Doing so without compromising environmental integrity is an even greater challenge. This study looks at the interdependencies between land and water resources, agricultural production and environmental outcomes in Latin America and the Caribbean (LAC), an area of growing importance in international agricultural markets. Special emphasis is given to the role of LAC’s agriculture for (a) global food security and (b) environmental sustainability. We use the International Model for Policy Analysis of Agricultural Commodities and Trade (IMPACT)—a global dynamic partial equilibrium model of the agricultural sector—to run different future production scenarios, and agricultural trade regimes out to 2050, and assess changes in related environmental indicators. Results indicate that further trade liberalization is crucial for improving food security globally, but that it would also lead to more environmental pressures in some regions across Latin America. Contrasting land expansion versus more intensified agriculture shows that productivity improvements are generally superior to agricultural land expansion, from an economic and environmental point of view. Finally, our analysis shows that there are trade-offs between environmental and food security goals for all agricultural development paths

Electron effective mass and mobility in heavily doped n-GaAsN probed by Raman scattering

We investigate inelastic light scattering by longitudinal optic phonon-plasmon coupled modes LOPCMs in a series of heavily Se-doped, n-type GaAs1−xNx epilayers with x 0.4%. We perform a line shape analysis of the LOPCM spectra to estimate the optical effective mass, mopt , and the scattering time of the conduction electrons in GaAsN. We use these results to evaluate an effective carrier mobility for our samples. The values thus obtained, which we compare with measured electron Hall mobilities, indicate that the x-dependence of the mobility in GaAs1−xNx is dominated by the scattering time, rather than by the variation of the electron effective mass. The Raman analysis yields mopt values that are lower than those obtained from the band anticrossing model. © 2008 American Institute of Physics.This work is supported by the Spanish Government Projects MAT 2004-0664 and MAT2007-63617, and Ramon y Cajal Program and the EPSRC, United Kingdom. 1M. Henini, Dilute Nitride Semiconductors Elsevier Science, AmsterdamPeer reviewe

Optical emission from Si O2 -embedded silicon nanocrystals: A high-pressure Raman and photoluminescence study

© 2015 American Physical Society. We investigate the optical properties of high-quality Si nanocrystals (NCs)/SiO2 multilayers under high hydrostatic pressure with Raman scattering and photoluminescence (PL) measurements. The aim of our study is to shed light on the origin of the optical emission of the Si NCs/SiO2. The Si NCs were produced by chemical-vapor deposition of Si-rich oxynitride (SRON)/SiO2 multilayers with 5- and 4-nm SRON layer thicknesses on fused silica substrates and subsequent annealing at 1150°C, which resulted in the precipitation of Si NCs with an average size of 4.1 and 3.3 nm, respectively. From the pressure dependence of the Raman spectra we extract a phonon pressure coefficient of 8.5±0.3cm-1/GPa in both samples, notably higher than that of bulk Si(5.1cm-1/GPa). This result is ascribed to a strong pressure amplification effect due to the larger compressibility of the SiO2 matrix. In turn, the PL spectra exhibit two markedly different contributions: a higher-energy band that redshifts with pressure, and a lower-energy band which barely depends on pressure and which can be attributed to defect-related emission. The pressure coefficients of the higher-energy contribution are (-27±6) and (-35±8)meV/GPa for the Si NCs with a size of 4.1 and 3.3 nm, respectively. These values are sizably higher than those of bulk Si(-14meV/GPa). When the pressure amplification effect observed by Raman scattering is incorporated into the analysis of the PL spectra, it can be concluded that the pressure behavior of the high-energy PL band is consistent with that of the indirect transition of Si and, therefore, with the quantum-confined model for the emission of the Si NCs.Work supported by the European Community’s Seventh Framework Programme (FP7/2007-2013) under grant agreement No. 245977 (project NASCEnT). Financial support by the Spanish Government through projects LEOMIS (TEC2012-38540-C02-01) and MAT2012-38664-C02-02 is also acknowledgedPeer Reviewe

Borehole image techniques applied to identification of chert and dolomite layers in lacustrine sediments

Geophysical logging tools, particularly ultrasonic acoustic borehole image techniques, are applied on two different wells (CP1 and CP2) to identify and characterize the lacustrine interval (40m) of the Camp dels Ninots maardiatreme infill (Pliocene, Catalan Coastal Ranges). The CP1 well was cored and also geophysical logs and oriented borehole images were acquired. CP2 hole was partially cored but logging (geophysics and borehole images) was fully undertaken. Continuous core recovery in CP1 is compared with oriented images and is further used to identify and characterize highly reflective signals in a section of CP2 borehole that was not cored. These signals are related to silicified zones and belong to discontinuous centimetric chert nodules, while indurated massive carbonates are characterized as intervals of continuous reflectance. Despite opal nodules (chert) can be relatively small, they have a distinctive response in the ultrasonic borehole images.Peer Reviewe

A spatially stabilized TDG based finite element framework for modeling biofilm growth with a multi-dimensional multi-species continuum biofilm model

We consider a model for biofilm growth in the continuum mechanics framework, where the growth of different components of biomass is governed by a time dependent advection–reaction equation. The recently developed time-discontinuous Galerkin (TDG) method combined with two different stabilization techniques, namely the Streamline Upwind Petrov Galerkin (SUPG) method and the finite increment calculus (FIC) method, are discussed as solution strategies for a multi-dimensional multi-species biofilm growth model. The biofilm interface in the model is described by a convective movement following a potential flow coupled to the reaction inside of the biofilm. Growth limiting substrates diffuse through a boundary layer on top of the biofilm interface. A rolling ball method is applied to obtain a boundary layer of constant height. We compare different measures of the numerical dissipation and dispersion of the simulation results in particular for those with non-trivial patterns. By using these measures, a comparative study of the TDG–SUPG and TDG–FIC schemes as well as sensitivity studies on the time step size, the spatial element size and temporal accuracy are presented. The final publication is available at Springer via http://dx.doi.org/10.1007/s00466-017-1388-1State of Lower Saxon

Real-Time Online Monitoring of the Ion Range by Means of Prompt Secondary Radiations

International audiencePrompt secondary radiations such as gamma rays and protons can be used for ion-range monitoring during ion therapy either on an energy-slice basis or on a pencil-beam basis. We present a review of the ongoing activities in terms of detector developments, imaging, experimental and theoretical physics issues concerning the correlation between the physical dose and hadronic processe

Cardiovascular risk factors and cognitive decline in older people with type 2 diabetes

AIMS/HYPOTHESIS: The aim of this work was to assess the role of well-established cardiovascular risk factors in the late-life cognitive decline of patients with type 2 diabetes. METHODS: Data from 831 participants (aged 60-75 years) attending the 4 year follow-up of the Edinburgh Type 2 Diabetes Study (ET2DS) were used. Smoking history (pack-years), BP, HbA1c, plasma glucose and cholesterol were determined at baseline clinics (single time measurements) and/or from serial data recorded on a clinical management database from diagnosis until recruitment ('historical' data). Principal component analysis derived a factor, g, of general ability from seven cognitive tests. Linear regression models of follow-up g were adjusted for baseline g to represent 4 year cognitive change. 'Accelerated late-life cognitive decline' was defined as scoring in the lowest tertile of '4 year cognitive change' regression scores. Analyses controlled for age and sex. RESULTS: A baseline history of moderate/heavy smoking (>/= 10 pack-years) and a 1% increased historical HbA1c (equivalent to an increase by 11 mmol/mol) predicted a 64% (OR 1.64; 95% CI 1.14, 2.34; p = 0.007) and 21% (OR 1.21; 95% CI 1.00, 1.45; p = 0.046) increased risk of accelerated cognitive decline, respectively. When treated as continuous measures, higher pack-years, historical HbA1c and historical BP emerged as significant independent predictors of 4 year decline in g (standardised beta range -0.07 to -0.14; all p </= 0.05). CONCLUSIONS/INTERPRETATION: Increased smoking and poorer glycaemic control (with relatively weaker findings for BP) during the life-course were independently associated with accelerated late-life cognitive decline. Where possible, evaluation is warranted of these risk factors as targets for intervention to reduce the burden of cognitive impairment in diabetes

Évolution de la contribution française à l'upgrade de LHCb

Ce document décrit l'évolution de la contribution française à l'upgrade de LHCb. Il s'inscrit dans le prolongement de la Lettre d'Intention [1], du Framework TDR [2], du document soumis au Conseil scientifique de l'IN2P3 le 21 juin 2012 [3], et des Technical Design Reports soumis au LHCC en novembre 2013 [4, 5]. Ces derniers concernent le détecteur de vertex et les détecteurs utilisés dans l'identification des particules. La contribution française s'est cristallisée autour de quatre grands projets : l'électronique front-end des calorimètres et du trajectographe à fibres scintillantes, le système de déclenchement de premier niveau et la carte de lecture à 40MHz commune à l'ensemble des sous-systèmes. Dans ce document nous décrivons les contributions envisagées et les ressources nécessaires pour mener à bien ces projets

2012 Activity Report of the Regional Research Programme on Hadrontherapy for the ETOILE Center

2012 is the penultimate year of financial support by the CPER 2007-2013 for ETOILE's research program, sustained by the PRRH at the University Claude Bernard. As with each edition we make the annual review of the research in this group, so active for over 12 years now. Over the difficulties in the decision-making process for the implementation of the ETOILE Center, towards which all our efforts are focussed, some "themes" (work packages) were strengthened, others have progressed, or have been dropped. This is the case of the eighth theme (technological developments), centered around the technology for rotative beam distribution heads (gantries) and, after being synchronized with the developments of ULICE's WP6, remained so by ceasing its activities, coinciding also with the retirement of its historic leader at IPNL, Marcel Bajard. Topic number 5 ("In silico simulations") has suffered the departure of its leader, Benjamin Ribba, although the work has still been provided by Branka Bernard, a former postdoctoral fellow in Lyon Sud, and now back home in Croatia, still in contract with UCBL for the ULICE project. Aside from these two issues (and the fact that the theme "Medico-economical simulations" is now directly linked to the first one ("Medical Project"), the rest of the teams are growing, as evidenced by the publication statistics at the beginning of this report. This is obviously due to the financial support of our always faithful regional institutions, but also to the synergy that the previous years, the European projects, the arrival of the PRIMES LabEx, and the national France Hadron infrastructure have managed to impulse. The Rhone-Alpes hadron team, which naturally includes the researchers of LPC at Clermont, should also see its influence result in a strong presence in France Hadron's regional node, which is being organized. The future of this regional research is not yet fully guaranteed, especially in the still uncertain context of ETOILE, but the tracks are beginning to emerge to allow past and present efforts translate into a long future that we all want to see established. Each of the researchers in PRRH is aware that 2013 will be (and already is) the year of great challenge : for ETOILE, for the PRRH, for hadron therapy in France, for French hadrontherapy in Europe (after the opening and beginning of treatments in the German [HIT Heidelberg, Marburg], Italian [CNAO, Pavia] and Austrian [MedAustron, Wien Neuerstadt]) centers. Let us meet again in early 2014 for a comprehensive review of the past and a perspective for the future ..