Aspects of the conformal operator product expansion in AdS/CFT correspondence

We present a detailed analysis of a scalar conformal four-point function obtained from AdS/CFT correspondence. We study the scalar exchange graphs in AdS and discuss their analytic properties. Using methods of conformal partial wave analysis, we present a general procedure to study conformal four-point functions in terms of exchanges of scalar and tensor fields. The logarithmic terms in the four-point functions are connected to the anomalous dimensions of the exchanged fields. Comparison of the results from AdS graphs with the conformal partial wave analysis, suggests a possible general form for the operator product expansion of scalar fields in the boundary CFT.Comment: 31 pages, LaTeX, accepted for publication in ATM

Telehealth methods to deliver multifactorial dietary interventions in adults with chronic disease: A systematic review protocol

Background: The long-term management of chronic diseases requires adoption of complex dietary recommendations, which can be facilitated by regular coaching to support sustained behaviour change. Telehealth interventions can overcome patient-centred barriers to accessing face-to-face programs and provide feasible delivery methods, ubiquitous and accessible regardless of geographic location. The protocol for this systematic review explains the methods that will be utilised to answer the review question of whether telehealth interventions are effective at promoting change in dietary intake and improving diet quality in people with chronic disease. Methods/design: A structured search of Medline, EMBASE, CINAHL, and PsychINFO, from their inception, will be conducted. We will consider randomised controlled trials which evaluate complex dietary interventions in adults with chronic disease. Studies must provide diet education in an intervention longer than 4 weeks in duration, and at least half of the intervention contact must be delivered via telehealth. Comparisons will be made against usual care or a non-telehealth intervention. The primary outcome of interest is dietary change with secondary outcomes relating to clinical markers pre-specified in the methodology. The process for selecting studies, extracting data, and resolving conflicts will follow a set protocol. Two authors will independently appraise the studies and extract the data, using specified methods. Meta-analyses will be conducted where appropriate, with parameters for determining statistical heterogeneity pre-specified. The GRADE tool will be used for determining the quality of evidence for analysed outcomes. Discussion: To date, there has been a considerable variability in the strategies used to deliver dietary education, and the overall effectiveness of telehealth dietary interventions for facilitating dietary change has not been reviewed systematically in adults with chronic disease. A systematic synthesis of telehealth strategies will inform the development of evidence-based telehealth programs that can be tailored to deliver dietary interventions specific to chronic disease conditions. Systematic review registration: PROSPERO CRD42015026398

Hydrological connectivity inferred from diatom transport through the riparian-stream system

Funding for this research was provided by the Luxembourg National Research Fund (FNR) in the framework of the BIGSTREAM (C09/SR/14), ECSTREAM (C12/SR/40/8854) and CAOS (INTER/DFG/11/01) projects. We are most grateful to the Administration des Services Techniques de l’Agriculture (ASTA) for providing meteorological data. We also acknowledge Delphine Collard for technical assistance in diatom sample treatment and preparation, François Barnich for the water chemistry analyses, and Jean-François Iffly, Christophe Hissler, Jérôme Juilleret, Laurent Gourdol and Julian Klaus for their constructive comments on the project and technical assistance in the field.Peer reviewedPublisher PD

N-mineralisation and Phosphorous: Important Elements in Decision Support for Grassland Systems

Leaching of N and P from extensively managed grasslands on organic soils varies considerably. In environmentally sensitive areas it is important to diminish leaching by appropriate agricultural management. In Denmark low grazing intensity and management without fertilisation have been given a high priority. The type of soil has not been equally in focus, and it seems that the effect of cutting, compared with grazing, results in a higher removal of nutrients (e.g. Benke et al., 1992) can be used more strategically. The objective of this case study was to combine data from management strategies with data from leaching studies on organic soils to elucidate the differences between type of management and type of soil for the potential leaching of N and P

Grande potencial.

Embora ainda pouco conhecido, o mirtilo é uma fruta muito apreciada no exterior, com crescimento de consumo de cerca de 20% ao ano. No Brasil, representa uma oportunidade de diversificação devido a seu elevado valor agregado.Número especial. Contém orientações gerais de como produzir mirtilo

Analytic structure of solutions to multiconfiguration equations

We study the regularity at the positions of the (fixed) nuclei of solutions to (non-relativistic) multiconfiguration equations (including Hartree--Fock) of Coulomb systems. We prove the following: Let {phi_1,...,phi_M} be any solution to the rank--M multiconfiguration equations for a molecule with L fixed nuclei at R_1,...,R_L in R^3. Then, for any j in {1,...,M} and k in {1,...,L}, there exists a neighbourhood U_{j,k} in R^3 of R_k, and functions phi^{(1)}_{j,k}, phi^{(2)}_{j,k}, real analytic in U_{j,k}, such that phi_j(x) = phi^{(1)}_{j,k}(x) + |x - R_k| phi^{(2)}_{j,k}(x), x in U_{j,k} A similar result holds for the corresponding electron density. The proof uses the Kustaanheimo--Stiefel transformation, as applied earlier by the authors to the study of the eigenfunctions of the Schr"odinger operator of atoms and molecules near two-particle coalescence points.Comment: 15 page

Comparaison de différents protocoles de spéciation séquentielle du phosphore dans des sédiments de rivière

Trois méthodes classiques de spéciation séquentielle du phosphore ont été appliquées aux sédiments de la rivière Sûre, à une sélection de ses affluents de taille variable, ainsi qu'aux sédiments du prébarrage Misère, un petit réservoir eutrophe situé sur la Sûre. Les protocoles comparés sont ceux de HIELTJES et LIJKLEMA (H et L), de PALUDAN et JENSEN (P et J) et de GOLTERMAN et BOOMAN (G et B).Le phosphore total des sédiments étudiés s'élève à 0,6 mg·P·g-1 séd. sec pour les petits sous-bassins expérimentaux (de l'ordre de 1 km2), à 0,8-1,0 mg·P·g-1 séd. sec pour les bassins de taille moyenne (20 à 320 km2) et à 1,8 mg·P·g-1 séd. sec pour le prébarrage Misère. Les schémas de (H et L) et de (P et J) reproduisent de façon similaire les différences qualitatives existant entre les sédiments. Toutefois les parts relatives des différentes fractions varient selon le protocole utilisé. Les rendements d'extraction obtenus avec le schéma de (G et B) sont sensiblement supérieurs aux deux autres méthodes et sont très liés aux teneurs en phosphore total des mêmes échantillons.Pour le P-labile, une bonne corrélation est obtenue entre les concentrations extraites selon les protocoles de (H et L) et (P et J) (R2 =0,84, P < 0,001) ; cependant les valeurs absolues sont 40 % supérieures pour le premier (H et L) qui utilise NH4Cl comme extractant au lieu de H2O. La fraction P- (Fe+Al) de (H et L) et la somme des fractions P-Fe et P-Al de (P et J) sont également bien corrélées (R2 =0,90, P < 0,001), mais avec des valeurs 30 % supérieures pour le second protocole (P et J) qui réalise l'extraction en deux étapes. La fraction P-Fe de (G et B) est moins bien corrélée à la fraction P-Fe de (P et J) (R2 =0,74, P < 0,01), et les résultats obtenus selon ces deux protocoles sont très éloignés en valeur absolue. Quant à la fraction P-Ca, les résultats du protocole de (G et B) ne sont ni corrélés ni similaires à ceux des deux autres schémas, en raison de la nature complètement différente des extractants appliqués.The Haute-Sûre river, with a rural watershed of 428 km2 is the principal entry of the Esch-sur-Sûre reservoir, which is mainly used for drinking-water supply. The role of particulate phosphorus (suspended matter and sediments) is important to maintain the trophic level of lakes, and in particular of reservoirs, often receiving higher external nutrient loads than natural lakes. Indeed, phosphorus flux in the Haute-Sûre basin occurs mainly in particulate form, closely linked to the hydrological and morphological conditions of its drainage basin. Several authors have shown that the fractionation of sedimentary phosphorus is strongly correlated with its bioavailability.This study was carried out in the framework of a larger project concerning the characterisation of the phosphorus from the sediments of the Sûre river watershed. The choice among the fractionation procedures described in literature and the comparison of the different results remains often difficult because of the different nature of the proposed extracting solutions, but also because of variable solid: liquid ratios, or the different exposure times proposed. Three traditional fractionation methods, HIELTJES and LIJKLEMA (H and L) (1980), PALUDAN and JENSEN (P and J) (1995) and GOLTERMAN and BOOMAN (G and B) (1988), were thus tested in the present study and applied to sediments from the Sûre river bed and a selection of its tributaries of variable size as well as to the Misère predam sediments, a small reservoir located upstream from the main reservoir.The first protocol (H and L) classes the sedimentary phosphorus in four fractions: labile-P obtained with a NO4C1 1M solution, (Fe+Al)-P with NaOH 0.1M as reagent, Ca-P with a HCl 0.5 M solution and residual-P obtained by difference of the three precedent fractions with total P. The second (P and J) separates sedimentary phosphorus in 6 fractions: labile-P extracted with H2O, Fe-P with a dithionite-bicarbonate solution (NaHCO3 0.11 M and Na2 S2 O4 0.11 M), Al-P with a NaOH 0.1 M solution after acidification of the supernatant to pH=1 and separation of the resultant precipitate, AH-P (humic acids - P) obtained after mineralisation (H2 SO4 /K2 SO4 sat. at 400°C) of the previous precipitate, Ca-P with a HCl 0.5 M solution, and finally residual-P after drying and mineralisation of the sediment having undergone all the previous steps (H2 SO4 /K2 SO4 sat. at 400°C). The third tested protocol (G and B) proposes chelates as extracting solutions: the fraction Fe-P with Ca-NTA/dithionite (CaCO3 0.04 M + NTA 0.02 M - Na2 S2 O4 0.045 M), and the Ca-P fraction with Na-EDTA 0.05 M at pH=8.The obtained results demonstrate a substantial difference between the sampled sediments. The total phosphorus content of the sampled sediments varied between 0.6 mg·P·g-1 dw for the small experimental basins (around 1 km2), 0.8 to 1.0 mg·P·g-1 dw for the medium-sized basins (20 to 320 km2) and 1.8 mg·P·g-1 dw for the Misère predam (lentic system). As regards the phosphorus fractionation, the (H and L) and the (P and J) procedures are concordant from the qualitative point of view, the relative importance of the different fractions varying nevertheless according to the used scheme. With the (G and B) method the extracted P fractions were highest. In relative terms (% P-fraction in relation to total-P), the sampled sediments have a very similar behaviour according to (G and B), the quantitative differences between samples being strongly correlated to their total phosphorus content.A good correlation was found between the labile-P fractions determined according to (H and L) and according to (P and J) (R2=0.84, P < 0.001) with however 40% higher values for (H and L). The P-(Fe+Al) fraction of (H and L) and the sum of the fractions P-Fe + P-Al of (P and J) are correlated as well (R2=0.90, P < 0.001) with 30% higher values for (P and J). Regarding the P-Fe fraction, the results obtained with the (G and B) and (P and J) protocols are correlated (R2=0.74, P < 0.01), but results are quantitatively quite different. The P-Ca fraction of the (G and B) protocol is badly correlated and very different from the two other procedures, because of the completely different nature of the extracting solutions