On small time asymptotics for rough differential equations driven by fractional Brownian motions

We survey existing results concerning the study in small times of the density of the solution of a rough differential equation driven by fractional Brownian motions. We also slightly improve existing results and discuss some possible applications to mathematical finance.Comment: This is a survey paper, submitted to proceedings in the memory of Peter Laurenc

Whole-Cell Analysis of Low-Density Lipoprotein Uptake by Macrophages Using STEM Tomography

Nanoparticles of heavy materials such as gold can be used as markers in quantitative electron microscopic studies of protein distributions in cells with nanometer spatial resolution. Studying nanoparticles within the context of cells is also relevant for nanotoxicological research. Here, we report a method to quantify the locations and the number of nanoparticles, and of clusters of nanoparticles inside whole eukaryotic cells in three dimensions using scanning transmission electron microscopy (STEM) tomography. Whole-mount fixed cellular samples were prepared, avoiding sectioning or slicing. The level of membrane staining was kept much lower than is common practice in transmission electron microscopy (TEM), such that the nanoparticles could be detected throughout the entire cellular thickness. Tilt-series were recorded with a limited tilt-range of 80° thereby preventing excessive beam broadening occurring at higher tilt angles. The 3D locations of the nanoparticles were nevertheless determined with high precision using computation. The obtained information differed from that obtained with conventional TEM tomography data since the nanoparticles were highlighted while only faint contrast was obtained on the cellular material. Similar as in fluorescence microscopy, a particular set of labels can be studied. This method was applied to study the fate of sequentially up-taken low-density lipoprotein (LDL) conjugated to gold nanoparticles in macrophages. Analysis of a 3D reconstruction revealed that newly up-taken LDL-gold was delivered to lysosomes containing previously up-taken LDL-gold thereby forming onion-like clusters

Macronutrient composition of three cucurbit species cultivated for seed consumption in Côte d’Ivoire

Dry seeds from three indigenous cucurbits [Citrullus lanatus var. citroides (Thumb.) Matsum. & Nakai.,Cucumeropsis mannii Naudin, and Cucumis melo var. agrestis L.] largely cultivated in Côte d’Ivoire andconsumed as sauce thickeners were analyzed for their proximate composition and compared to a locallandrace of peanut (Arachis hypogae L.). The protein contents were 29.23±1.74, 36±2.17, 29.55±2.09, and24.79±0.44% for C. lanatus, C. mannii, C. melo, and A. hypogaea, respectively. The highest estimates offat content was observed with C. lanatus (56.67±4.90%) followed in decreased order by the peanut(48.17±1.60%), C. mannii (45.89±4.73%), and C. melo (42.67±3.43%). The carbohydrate content for C.lanatus was 9.87±3.52% and C. mannii and C. melo had 13.86±3.64 and 23.18±4.80%, respectively. C.melo was then the highest in carbohydrate content whereas A. hypogaea has the lowest value(6.39±2.66%). The crude fibre contents for C. lanatus, C. mannii, and C. melo averaged 2.87±1.07,2.30±0.85, and 2.94±0.75%, respectively. The three cucurbit species were markedly low in fibre value,compared to the analyzed peanut (17.14±3.82%). As expected on the basis of several published data,ash content of seeds from indigenous cucurbits was generally low: 1.33±0.52% (C. lanatus), 2.50±1.38%(C. mannii), and 1.67±0.82% (C. melo)

Heritability and number of genes controlling seed yield in bottle gourd

Bottle gourd [ Lagenaria siceraria (Molina) Standley] is an important tropical specie characterised by a wide diversity and a low yield, mainly due to no selection for improved varieties. Selection for a particular trait depends on the relative importance of genetic and nongenetic factors influencing the expression of phenotypic differences among crop population. The objective of this study was to examine the genetics basis of seed yield and yield components, by crossing oleaginous type and calabash-type of bottle gourd [Lagenaria siceraria (Molina) Standley]. The parental lines (P1 and P2), with the respective hybrids F1 and F2 generations, were grown in two contrasted locations in terms of pedoclimatic conditions. Results showed no significant difference between the two locations for studies traits (P=0.06). For seed yield per plant, 100-seed weight per fruit, and number of seeds per fruit, a positive hypothetical heterosis was observed when calabash type was a maternal parent. Negative real heterosis was observed in all studied traits. For all traits, the genetic variance was higher than the environmental variance in the most of the crosses, implying greatest genes action in the expression of studies traits. Heritability was medium for fruit weight (mean, 42.12%) and seed number per fruit (mean, 47.36%). But for 100-seed weight (mean, 61.00%) and seed yield per plant (mean, 53.28%) high heritability were observed. The minimum number of genes that controlled the expression of 100-seed weight (0.58), seed yield per plant (1.58) and number of seeds per plant (0.98) was low (close to 1). These observations suggest that distinct genotypes for interest characters would be fixed by using a small number of selfing generations (F3 to F4) in West African bottle gourd.La gourde ol\ue9agineuse est une esp\ue8ce tropicale caract\ue9ris\ue9e par une grande diversit\ue9 agromorphologique et un faible rendement qui s\u2019explique par l\u2019absence de s\ue9lection pour les vari\ue9t\ue9s am\ue9lior\ue9es. La s\ue9lection d\u2019un caract\ue8re d\u2019int\ue9r\ueat d\ue9pend de l\u2019importance relative des facteurs g\ue9n\ue9tiques et non g\ue9n\ue9tiques qui influencent l\u2019expression des diff\ue9rences ph\ue9notypiques observ\ue9es dans la population \ue9tudi\ue9. L\u2019objectif de cette \ue9tude est d\u2019examiner les bases g\ue9n\ue9tiques et le nombre de g\ue8nes contr\uf4lant le rendement en graines et ses composantes en croisant quatre accessions de Lagenaria siceraria (Molina) Standley\ua0: deux du type calebasse (NI-CM001 et NI-CSM001) et deux du type ol\ue9agineux (NI-232 et NI-135). Pour se fait, les lign\ue9es parentales (P1 et P2) et les g\ue9n\ue9rations hybrides (F1 et F2) ont \ue9t\ue9 cultiv\ue9s sur deux sites contrast\ue9s (nord et sud de la C\uf4te d\u2019Ivoire). Les r\ue9sultats de l\u2019analyse multivari\ue9 de la variance (MANOVA) n\u2019ont montr\ue9 aucune diff\ue9rence significative entre les deux sites pour l\u2019ensemble des caract\ue8res \ue9tudi\ue9s (F = 2,29; P = 0,06). L\u2019h\ue9t\ue9rosis th\ue9orique (parent moyen) \ue9tait positive lorsque le type de calebasse servait de parent maternel pour le poids de 100 graines par fruit, le rendement des graines par plante et le nombre de graines par fruit, alors que l\u2019h\ue9t\ue9rosis r\ue9elle (meilleur parent) \ue9tait n\ue9gative pour ces caract\ue8res. L\u2019h\ue9ritabilit\ue9 \ue9tait moyenne pour le poids des fruits (42,12%) et le nombre de graines par fruit (47,36%). Cependant, une forte h\ue9ritabilit\ue9 a \ue9t\ue9 observ\ue9e pour le poids de 100 graines (61,00%) et le rendement en graines par plante (53,28%). Un faible nombre g\ue8nes a \ue9t\ue9 observ\ue9 dans l\u2019expression de la masse de 100 graines (0,58), le rendement en graines par plante (1,58) et le nombre de graines par plante (0,98). Ces r\ue9sultats sugg\ue8rent que dans les programmes futurs d\u2019am\ue9lioration de L. siceraria, la s\ue9lection des g\ue9notypes les plus performants pour les composantes du rendement pourrait se faire d\ue8s les g\ue9n\ue9rations d\u2019autof\ue9condation F3 ou F4

Explicit formulae in probability and in statistical physics

We consider two aspects of Marc Yor's work that have had an impact in statistical physics: firstly, his results on the windings of planar Brownian motion and their implications for the study of polymers; secondly, his theory of exponential functionals of Levy processes and its connections with disordered systems. Particular emphasis is placed on techniques leading to explicit calculations.Comment: 14 pages, 2 figures. To appear in Seminaire de Probabilites, Special Issue Marc Yo

Reliability testing of tendon disease using two different scanning methods in patients with rheumatoid arthritis

Objective. To assess the intra- and interobserver reliability of musculoskeletal ultrasonography (US) in detecting inflammatory and destructive tendon abnormalities in patients with RA using two different scanning methods.Methods. Thirteen observers examined nine patients with RA and one healthy individual in two rounds independently and blindly of each other. Each round consisted of two consecutive examinations, an anatomy-based examination and a free examination according to personal preferences. The following tendons were evaluated: wrist extensor compartments 2, 4 and 6, finger flexor tendons 3 and 4 at MCP level, tibialis posterior tendon and both peronei tendons. Overall, positive and negative agreements and \u3ba-values for greyscale (GS) tenosynovitis, peritendinous power Doppler (PPD) signal, intratendinous power Doppler (IPD) signal and GS tendon damage were calculated.Results. Intraobserver \u3ba-value ranges were 0.53-0.55 (P < 0.0005) for GS tenosynovitis, 0.61-0.64 (P < 0.0005) for PPD signal, 0.65-0.66 (P < 0.0005) for IPD signal and 0.44-0.53 (P < 0.0005) for GS tendon damage. For interobserver reliability, substantial overall agreement ranged from 80 to 89% for GS tenosynovitis, 97 to 100% for PPD signal, 97 to 100% for IPD signal and 97 to 100% for GS tendon damage. Results were independent of scanning technique.Conclusion. Intraobserver reliability for tenosynovitis and tendon damage varied from moderate for GS to good for PD. Overall interobserver reliability for tenosynovitis and tendon damage was excellent both for GS and PD. This qualitative scoring system may serve as the first step to a semi-quantitative score for tendon pathology. \ua9 The Author 2012. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved

Reliability testing of tendon disease using two different scanning methods in patients with rheumatoid arthritis

Objective. To assess the intra- and interobserver reliability of musculoskeletal ultrasonography (US) in detecting inflammatory and destructive tendon abnormalities in patients with RA using two different scanning methods.Methods. Thirteen observers examined nine patients with RA and one healthy individual in two rounds independently and blindly of each other. Each round consisted of two consecutive examinations, an anatomy-based examination and a free examination according to personal preferences. The following tendons were evaluated: wrist extensor compartments 2, 4 and 6, finger flexor tendons 3 and 4 at MCP level, tibialis posterior tendon and both peronei tendons. Overall, positive and negative agreements and κ-values for greyscale (GS) tenosynovitis, peritendinous power Doppler (PPD) signal, intratendinous power Doppler (IPD) signal and GS tendon damage were calculated.Results. Intraobserver κ-value ranges were 0.53-0.55 (P < 0.0005) for GS tenosynovitis, 0.61-0.64 (P < 0.0005) for PPD signal, 0.65-0.66 (P < 0.0005) for IPD signal and 0.44-0.53 (P < 0.0005) for GS tendon damage. For interobserver reliability, substantial overall agreement ranged from 80 to 89% for GS tenosynovitis, 97 to 100% for PPD signal, 97 to 100% for IPD signal and 97 to 100% for GS tendon damage. Results were independent of scanning technique.Conclusion. Intraobserver reliability for tenosynovitis and tendon damage varied from moderate for GS to good for PD. Overall interobserver reliability for tenosynovitis and tendon damage was excellent both for GS and PD. This qualitative scoring system may serve as the first step to a semi-quantitative score for tendon pathology. © The Author 2012. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved