The topological structure of scaling limits of large planar maps

We discuss scaling limits of large bipartite planar maps. If p is a fixed integer strictly greater than 1, we consider a random planar map M(n) which is uniformly distributed over the set of all 2p-angulations with n faces. Then, at least along a suitable subsequence, the metric space M(n) equipped with the graph distance rescaled by the factor n to the power -1/4 converges in distribution as n tends to infinity towards a limiting random compact metric space, in the sense of the Gromov-Hausdorff distance. We prove that the topology of the limiting space is uniquely determined independently of p, and that this space can be obtained as the quotient of the Continuum Random Tree for an equivalence relation which is defined from Brownian labels attached to the vertices. We also verify that the Hausdorff dimension of the limit is almost surely equal to 4.Comment: 45 pages Second version with minor modification

Novel deletions causing pseudoxanthoma elasticum underscore the genomic instability of the ABCC6 region

Mutations in ABCC6 cause pseudoxanthoma elasticum (PXE), a heritable disease that affects elastic fibers. Thus far, >200 mutations have been characterized by various PCR-based techniques (primarily direct sequencing), identifying up to 90% of PXE-causing alleles. This study wanted to assess the importance of deletions and insertions in the ABCC6 genomic region, which is known to have a high recombinational potential. To detect ABCC6 deletions/insertions, which can be missed by direct sequencing, multiplex ligation-dependent probe amplification (MLPA) was applied in PXE patients with an incomplete genotype. MLPA was performed in 35 PXE patients with at least one unidentified mutant allele after exonic sequencing and exclusion of the recurrent exon 23-29 deletion. Six multi-exon deletions and four single-exon deletions were detected. Using MLPA in addition to sequencing, we expanded the ABCC6 mutation spectrum with 9 novel deletions and characterized 25% of unidentified disease alleles. Our results further illustrate the instability of the ABCC6 genomic region and stress the importance of screening for deletions in the molecular diagnosis of PXE. Journal of Human Genetics (2010) 55, 112-117; doi: 10.1038/jhg.2009.132; published online 15 January 201

Tangling clustering of inertial particles in stably stratified turbulence

We have predicted theoretically and detected in laboratory experiments a new type of particle clustering (tangling clustering of inertial particles) in a stably stratified turbulence with imposed mean vertical temperature gradient. In this stratified turbulence a spatial distribution of the mean particle number density is nonuniform due to the phenomenon of turbulent thermal diffusion, that results in formation of a gradient of the mean particle number density, \nabla N, and generation of fluctuations of the particle number density by tangling of the gradient, \nabla N, by velocity fluctuations. The mean temperature gradient, \nabla T, produces the temperature fluctuations by tangling of the gradient, \nabla T, by velocity fluctuations. These fluctuations increase the rate of formation of the particle clusters in small scales. In the laboratory stratified turbulence this tangling clustering is much more effective than a pure inertial clustering that has been observed in isothermal turbulence. In particular, in our experiments in oscillating grid isothermal turbulence in air without imposed mean temperature gradient, the inertial clustering is very weak for solid particles with the diameter 10 microns and Reynolds numbers Re =250. Our theoretical predictions are in a good agreement with the obtained experimental results.Comment: 16 pages, 4 figures, REVTEX4, revised versio

Electrodeposition of In2S3 buffer layer for Cu(In,Ga)Se2 solar cells

AbstractThe electrochemical deposition of In2S3 thin films was carried out from an aqueous solution of InCl3 and Na2S2O3. The effect of the potential of deposition was studied on the cell parameters of CIGSe based solar cells. The obtained films depending on the deposition potential and thickness exhibited complete substrate coverage or nanocolumnar layers. XPS measurements detected the presence of indium sulphide and hydroxide depending on the deposition parameters. Maximum photoelectric conversion efficiency of 10.2% was obtained, limited mainly by a low fill factor (56%). Further process optimization is expected to lead to efficiencies comparable to CdS buffer layers

Random trees between two walls: Exact partition function

We derive the exact partition function for a discrete model of random trees embedded in a one-dimensional space. These trees have vertices labeled by integers representing their position in the target space, with the SOS constraint that adjacent vertices have labels differing by +1 or -1. A non-trivial partition function is obtained whenever the target space is bounded by walls. We concentrate on the two cases where the target space is (i) the half-line bounded by a wall at the origin or (ii) a segment bounded by two walls at a finite distance. The general solution has a soliton-like structure involving elliptic functions. We derive the corresponding continuum scaling limit which takes the remarkable form of the Weierstrass p-function with constrained periods. These results are used to analyze the probability for an evolving population spreading in one dimension to attain the boundary of a given domain with the geometry of the target (i) or (ii). They also translate, via suitable bijections, into generating functions for bounded planar graphs.Comment: 25 pages, 7 figures, tex, harvmac, epsf; accepted version; main modifications in Sect. 5-6 and conclusio

Coping with citizen demands: a field study of suckling processes in dairy herds

In dairy farms calves and cows are usually separated shortly after birth but this practice raises the question of animal welfare. This social concern may lead to bring back dairy calves to their mother. Even though suckling is quite seldom in dairy production, some farmers are using such a practice for many years. The present study aims to better know farmer’s motivations, practical implementation and farmer’s perception of the impact of suckling on performance and animal behaviour. In January 2018 a semi-quantitative survey was performed on 44 farms where calves suckle at least 24 hours their mother or a nurse cow. The farming systems differed on the size (20 to 140 cows), the type (19 conventional, 25 organic farms), the suckling (28 by the mothers, 16 by nurses), and the breed. Results indicate that main farmers’ motivations are calves’ health (52%), better working conditions (41%) and saving time (34%), with little consideration on animal welfare (7%). Numerous practices were found in terms of allowance of daily cow-calf contact and suckling duration with a difference between male and female calves. According to farmers, these practices were efficient to improved calves’ health (70%), save time (75%) and improved working conditions (52%). Weaning was considered as a stressful situation, especially after long suckling periods. Cow mooing usually stopped 2.5 d after weaning. At least 34 farmers are fully satisfied with this practice. The main challenge appears to be the management of the wildness of future heifers, by investing time to manipulate calves before weaning. The results of this survey could help to propose solutions to farmers who want to cope with the societal demand of keeping calves with dams in dairy herds

Bioactivity and structural properties of chimeric analogs of the starfish SALMFamide neuropeptides S1 and S2

The starfish SALMFamide neuropeptides S1 (GFNSALMFamide) and S2 (SGPYSFNSGLTFamide) are the prototypical members of a family of neuropeptides that act as muscle relaxants in echinoderms. Comparison of the bioactivity of S1 and S2 as muscle relaxants has revealed that S2 is ten times more potent than S1. Here we investigated a structural basis for this difference in potency by comparing the bioactivity and solution conformations (using NMR and CD spectroscopy) of S1 and S2 with three chimeric analogs of these peptides. A peptide comprising S1 with the addition of S2's N-terminal tetrapeptide (Long S1 or LS1; SGPYGFNSALMFamide) was not significantly different to S1 in its bioactivity and did not exhibit concentration-dependent structuring seen with S2. An analog of S1with its penultimate residue substituted from S2 (S1(T); GFNSALTFamide) exhibited S1-like bioactivity and structure. However, an analog of S2 with its penultimate residue substituted from S1 (S2(M); SGPYSFNSGLMFamide) exhibited loss of S2-type bioactivity and structural properties. Collectively, our data indicate that the C-terminal regions of S1 and S2 are the key determinants of their differing bioactivity. However, the N-terminal region of S2 may influence its bioactivity by conferring structural stability in solution. Thus, analysis of chimeric SALMFamides has revealed how neuropeptide bioactivity is determined by a complex interplay of sequence and conformation

Déléguer l'allaitement des veaux laitiers aux vaches ? Résultats d'enquêtes auprès des éleveurs

La séparation précoce mère-veau est une pratique courante dans la plupart des élevages laitiers, mais est sujette à de nombreuses interrogations tant chez les éleveurs (coûts engendrés, travail) que dans la société (bien-être animal). Des pratiques alternatives mises en place par certains éleveurs permettent aux veaux d'être allaités par leur mère ou une autre vache, appelée « nourrice ». Quoiqu’anciennes, ces pratiques demeurent peu connues et leur intégration aux conditions d’élevages modernes questionne. Des enquêtes ont ainsi été réalisées en 2018 pour connaître la motivation des éleveurs, la diversité et les conséquences de ces pratiques sur les résultats techniques. Cent deux élevages, identifiés par des réseaux divers (conseil en élevage, chambres d’agriculture, coopératives…), ont été enquêtés dans le Grand Ouest (n = 50), le Grand Est (n = 41) et le Massif central (n = 11), par téléphone (n = 56) ou sur place (n = 46). La taille médiane des troupeaux est de 60 vaches laitières (8 à 210), principalement constitués de vaches de race Montbéliarde et Holstein. Les élevages sont pour moitié en agriculture biologique (56%), avec une grande diversité de systèmes de traite et de logement (salle de traite en épi, robot, stabulation entravée, libre à logettes…). Trois grandes conduites d'allaitement des veaux, de la naissance à la vente ou au sevrage, ont été identifiées : 1/ les veaux sont allaités exclusivement par leur mère ; 2/ les veaux sont élevés par leur mère puis reçoivent une alimentation lactée artificielle (poudre ou lait entier) ; 3/ les veaux sont élevés par leur mère puis sous une vache nourrice. Elles diffèrent souvent au sein d’un même élevage (n = 62) entre les veaux destinés à la vente (mâles ou femelles) et les velles de renouvellement. La diversité des systèmes d'allaitement se retrouve dans tous les types d'élevages, quelle que soit leur taille ou leur localisation géographique. L'amélioration de la santé des animaux (n = 52), la diminution du temps de travail (n = 47) et des coûts d’élevage (n = 32) sont les principales motivations des éleveurs à mettre en place ces pratiques. Pour 80% d’entre eux, ces pratiques alternatives ont entrainé une diminution de la fréquence des diarrhées des veaux et une amélioration de leur croissance. La séparation tardive vache-veau demeure le point négatif de ces pratiques, avec des périodes de meuglements de 2,4 jours en moyenne. Certains éleveurs, ayant utilisé puis abandonné ces pratiques, pointent aussi d’autres limites (problèmes sanitaires, bâtiments inadaptés). Cette enquête, qui a permis de mieux connaître les pratiques d'allaitement des veaux laitiers par leur mère et sous nourrice, va être complétée par des enquêtes similaires et des expérimentations en fermes, au niveau européen, afin d’avoir une vision plus large de ces pratiques et de leurs impacts

Preparation of Cu(In,Ga)Se2 photovoltaic absorbers by an aqueous metal selenite co-precipitation route

In this paper, we report a novel and simple solution-based approach for the fabrication of chalcopyrite Cu(In,Ga)Se2 thin film solar cells. An aqueous co-precipitation method based on metal selenites, M2(SeO3)x (M = Cu, In, Ga) precursors was investigated. The resulting powder, dispersed in a binder to form an ink, was coated on a substrate by doctor blade technique. A soft annealing treatment allowed the reduction of metal selenites into selenides. Further rapid thermal processing (RTP) achieved crystalline chalcopyrite absorber. The obtained layer provides good compositional control and adequate morphology for solar cell applications. The water-based synthesis is a sustainable and simple procedure, and together with doctor blade printing, provides a potential cost-effective advantage over conventional fabrication processes (vacuum-based deposition techniques). The short circuit current (JSC), open circuit voltage (VOC), fill factor (FF), and total area power conversion efficiency (Eff.) of the device are 26 mA/cm2, 450 mV, 62%, and 7.2%, respectively. The effective band gap of 1.12 eV confirmed Ga-incorporation in the CIGS crystal lattice.This work was supported by the Spanish Ministry of Science and Competiveness under INNPACTO Program (IPT-2011-0913- 920000). The authors would like to thanks to Manuel Ocana Jurado ~ (ICMS-CISC) for his help in the XPS measurements. L. Oliveira would like to thank the support of the National Council for Scientific and Technological Development (CNPq) e Brazil