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Background Williams Beuren Syndrome is a multisystemic disorder manifested by congenital heart defects associated with dysmorphic features, intellectual delay, and a particular behavioural profile due to a microdeletion in 7q11.2. Methods To establish a genotype-phenotype correlation; we carried out a molecular cytogenetic analysis on 31 Tunisian WBS patients using the CGH-array and FISH techniques. Results 6 patients were investigated by CGH-array. All of them had a typical WBS deletion ranging from 1.4Mb to 1.7Mb. Curiously in 2 patients autistic spectrum disorders were noted in contrast to the behavioural profile generally observed in the other patients which are characterized by good contact. If we analyse the distal region of the generally deleted region, we found that the HIP1 gene is included. HIP1 encodes a central nervous system expressed protein and is considered the candidate gene for autism in this region. Conclusion Considering the presence of autism, a CGH analysis is essential to determine the exact etiology of this disorder, which seems strange for this syndrome, but is becoming progressively frequent. We suggest that alteration of the HIP1 gene could be indirectly responsible for autism, but specific environmental factors might act as risk factors triggering the development of this trait...

A finite strain mean-field homogenization (MFH) formulation is proposed for a class of composites where multiple phases of solid inclusions or cavities are embedded in a continuum matrix. Local constitutive equations of each solid phase are based on a multiplicative decomposition of the deformation gradient onto elastic and inelastic parts and hyperelastic-plastic stress-strain relations. For the special situation of hyperelastic constituents, a mixed variational formulation is presented which handles both compressible and quasi-incompressible cases within the same framework. A special emphasis is put on the proper definition of various macroscopic stress measures and tangent operators. For an extended Mori-Tanaka MFH model, numerical algorithms were developed and implemented. The MFH predictions were extensively tested against direct finite element simulations of representative volume elements or unit cells, for several heterogeneous microstructures under various loadings.

The expectations on the material performance have never been higher: lighter, stronger, greener and multifunctional materials are in the midst of the revolution speed-up of many industries. By combining different materials, or different states of the same material, one can greatly improve some particular properties to achieve performance that could not be attained with a single material. Understanding the physical behaviour and predicting accurately the effective properties of heterogeneous materials is essential in order to take full advantage of their functionalities and tailor their properties according to the destined application. To address this challenge, multi-scale modeling approaches with predictive capabilities have been developed and allow to link information about the microstructure of the material with its macroscopic, or engineering, properties. In this thesis, we investigate several issues related to the homogenization of composite and porous materials and try to answer some of the remaining questions via both analytical and numerical approaches. We adopt a mean-field homogenization (MFH) approach, while full-field finite element technique will serve as a tool for evaluating and verifying homogenization models that will be developed. Concretely, we aim at addressing the following issues that are still open in the literature: - To which extent are MFH models able to predict effective behavior of highly porous and cellular solids in linear elasticity and visco-elaticity? - Is it possible to derive a macroscopic yield function accounting for interactions between voids and thus enhance the original Gurson’s model predictions for moderate to high porosities without adding fitting parameters? - For an anisotropic porous matrix material, is there an alternative to the existing literature on analytical derivation of macroscopic yield criterion? - How to generalize MFH schemes from linear elasticity to finite strain elasto-plasticity? (FSA - Sciences de l'ingénieur) -- UCL, 2018

Cells of Fanconi anemia (FA) is characterized by cellular and chromosomal hypersensitivity to DNA cross-linking agents. We tested mitomycin C at 25 ng/mL, 40 ng/mL and diepoxybutane 0.1 μg/mL in order to select a reference technique in the diagnosis of AF. We also studied the mitotic segregation of sex chromosomes. Our study focused on 73 patients with aplastic anemia suspecting AF and also 17 healthy controls. Thus, the MMC 25 ng/mL with a sensitivity to detect AF cells. DEB, by contrast, showed better specificity. FISH study shows the presence of instability in the AF mitotic cells. The association for routine diagnosis of MMC 25 ng/mL and DEB 0.1 mcg/mL, and the search for a mitotic instability by FISH is the best way of cytogenetic diagnosis of AF.

The objective of this paper is the prediction of the macroscopic behaviour of open-cell foams in elasticity and viscoelasticity as function of their microstructure by using a micromechanical approach. Open cellular materials are characterised by remarkable mechanical properties with light weight. Such materials are largely used in various applications mainly in energy absorption. Polyurethane foam is used as an application once its microstructure is majorly described by an open-cell foam. Finite Element computations are performed on a unit cell subjected to periodic boundary conditions. Then, a micromechanical model based on Cosserat homogenisation framework is performed to predict the macroscopic elasticity. The linear viscoelastic behaviour is deduced from elastic results by taking advantage of correspondence principle. Finally, the results are confronted to various models developed in literature.

International audience; The present study deals with a strength criterion for ductile porous materials consisting in a Hill type orthotropic matrix containing spherical voids. The originality of the study lies into an attempt to develop an approximate static Limit Analysis for this class of materials, based on the recent work of Cheng et al. (2014) initially proposed for isotropic von Mises matrix. To this end, we considered, in the framework of a statical limit analysis framework, a trial stress field complying with the boundary conditions of the homogenization problem. Interestingly, the proposed procedure delivers an anisotropic macroscopic criterion which is not only pressure dependent, but exhibits an original sensitivity to the sign of the third invariant of the stress deviator. The obtained results are discussed and compared to existing theoretical models, to numerical bounds and to recently available Finite Element results. Finally, we provide the plastic strain rate equations and the void evolution law which are crucial for formulating the failure of anisotropic ductile metals. The influence of the plastic anisotropy on these constitutive equations is illustrated.

PurposeThe purpose of this paper is to model the relationship between manufacturing parameters, especially finishing treatments and instrumental tactile properties measured by Kawabata evaluation system.Design/methodology/approachTwo soft computing approaches, namely artificial neural network (ANN) and fuzzy inference system (FIS), have been applied to predict the compression and surface properties of knitted fabrics from finishing process. The prediction accuracy of these models was evaluated using both the root mean square error and mean relative percent error.FindingsThe results revealed the model's ability to predict instrumental tactile parameters based on the finishing treatments. The comparison of the prediction performances of both techniques showed that fuzzy models are slightly more powerful than neural models.Originality/valueThis study provides contribution in industrial products engineering, with minimal number of experiments and short cycles of product design. In fact, models based on intelligent techniques, namely FIS and ANNs, were developed for predicting instrumental tactile characteristics in reference to finishing treatments.

In the present study, the effects of structure and process parameters on the tactile properties of cotton-knitted fabrics had been investigated. The examined parameters were elastane plating, count of yarns and English gauge of knitting machine. The tactile quality was measured using sensory analysis and instrumental techniques. The obtained results showed that the variations of the production parameters induce a significant effect on 11 sensory attributes assessed by a French-trained panel. Compression and surface properties, measured by the Kawabata Evaluation System are affected too by these variations. Using principal component analysis, the correlation between instrumental data and sensory scores had highlighted compression resilience, geometrical and frictional roughness as significant parameters. PRACTICAL APPLICATIONS The practical issue of the research presented in this article is to provide to textile and garment manufacturers the existed relationship between production parameters and the tactile properties of knitted fabrics. Although several studies on the tactile properties of woven fabrics were performed, a lack in the investigations intertwining tactile characteristics of knits from instrumental and sensory techniques has been noted. The correlation between the sensory attributes, assessed by a French-trained panel, and the compression and surface properties measured by the Kawabata Evaluation System is established.

Good textile sensory characteristics required by the consumers incites textile industrialists to improve the sensory properties of fabrics. Therefore, several textile finishing processes have been proposed to improve the feel of fabrics. This work investigates the effects of some finishing treatments on the tactile properties using sensory analysis. The studied finishing treatments, namely bleaching, dyeing in different conditions, bio-polishing, softening, emerizing and calendaring, were applied on 100% cotton knitted fabrics. The obtained sensory properties of treated fabrics are in accordance with each finishing treatment aim. Hence, the bio-polishing treatment confers to fabrics a less hairy feeling, softening procures to fabrics a more soft, hairy and elastic feeling and emerizing leads to a more hairy and soft feeling. PRACTICAL APPLICATIONS The practical use of the research presented in this paper is in the sensory evaluation of textile products. The tactile quality of fabrics is an important selling argument. Thus, the textile industrialists try to optimize the production, and especially finishing processes to improve the fabrics tactile feeling. Therefore, it seems necessary to develop tools describing and grading the sensory quality of the produced fabrics for similar consumers' evaluation.

The wear comfort desired by the consumer is leading to increased use of fabrics containing elastane filaments. However, the elastane's ratio is an important factor influencing the fabric's mechanical properties. Thus, we study the effect of elastane's ratio and finishing process on the elasticity of denim whose weft yarns are cotton covered elastane-core spun yarns having the same twist factor and various elastane's ratio.

Composite yarns with elastane have become more and more used to take advantage of the filament properties. Indeed, the elastane filament improves the yarn's elasticity. However, the elastane ratio is an important factor influencing the yarn's strength. Thus, we study the effect of elastane ratio on the mechanical properties of cotton covered elastane-core spun yarns with the same twist factor and various elastane ratios. This study indicates that the elastane ratio is an important factor influencing the tenacity and elongation at break of yarns.

A water sample from the North Sea was used to isolate the abundant heterotrophic bacteria that are able to grow on complex marine media. Isolation was by serial dilution and spread plating. Phylogenetic analysis of nearly complete 16S rRNA gene sequences revealed that one of the strains, HEL-45T, had 97·4 % sequence similarity to Sulfitobacter mediterraneus and 96·5 % sequence similarity to Staleya guttiformis. Strain HEL-45T is a Gram-negative, non-motile rod and obligate aerobe and requires sodium and 1–7 % sea salts for growth. It contains storage granules and does not produce bacteriochlorophyll. Optimal growth temperatures are 25–30 °C. The DNA base composition (G+C content) is 60·1 mol%. Strain HEL-45T has Q10 as the dominant respiratory quinone. The major polar lipids are phosphatidyl glycerol, diphosphatidyl glycerol, phosphatidyl choline, phosphatidyl ethanolamine and an aminolipid. The fatty acids comprise 18 : 1ω7c, 18 : 0, 16 : 1ω7c, 16 : 0, 3-OH 10 : 0, 3-OH 12 : 1 (or 3-oxo 12 : 0) and traces of an 18 : 2 fatty acid. Among the hydroxylated fatty acids only 3-OH 12 : 1 (or 3-oxo 12 : 0) appears to be amide linked, whereas 3-OH 10 : 0 appears to be ester linked. The minor fatty acid components (between 1 and 7 %) allow three subgroups to be distinguished in the Sulfitobacter/Staleya clade, placing HEL-45T into a separate lineage characterized by the presence of 3-OH 12 : 1 (or 3-oxo 12 : 0) and both ester- and amide-linked 16 : 1ω7c phospholipids. HEL-45T produces indole and derivatives thereof, several cyclic dipeptides and thryptanthrin. Phylogenetic analysis of 16S rRNA gene sequences and chemotaxonomic data support the description of a new genus and species, to include Oceanibulbus indolifex gen. nov., sp. nov., with the type strain HEL-45T (=DSM 14862T=NCIMB 13983T).

In the present investigation we are concerned with the anisotropic plastic behavior of porous ductile materials. We consider a Hill type anisotropic matrix containing spherical voids and we aim to account for the overall plastic anisotropy and derive a new yield criterion. The originality of this work is to attempt to develop an approximate lower bound macroscopic criterion. For this purpose we proceed by a statical limit analysis proce- dure in the light of the recent work of Cheng et al. 1 which was initially proposed for isotropic von Mises matrix. A trial stress field is thus used for the derivation of the new yield loci. Interestingly, the obtained quasi-lower bound criterion is macroscopically anisotropic and shows the influence of both the plastic anisotropy of the matrix, the first and second invariants of the macroscopic stress and the sign of the third invariant of the stress deviator (J3). The corresponding yield surface is slightly asymmetric with respect to either the deviatoric (Σm = 0) or hydrostatic (Σe = 0) axis. The obtained results are discussed and compared to existing theoretical models, namely the upper bound yield criterion of Benzerga et al. 2, numerical data given by Pastor et al. 3 and to recent Finite Elements results of Morin et al. 4 . Finally, we provide the plastic strain rate equations and the void evolution law which is crucial for predicting the failure of ductile metals. The influence of the plastic anisotropy on these constitutive equations is shown. In the figure below we compare the yield curves according to the new criterion and corresponding to J3 > 0 and to J3 < 0 with those pertaining to Benzerga et al. for a porosity p = 0.05 and p = 0.1 respectively. The zoom on a portion of the figure displays a slight asymmetry of the yield surface.

In this paper, we focus on the prediction of the elastic and linear viscoelastic properties of porous solids based on their microstructure for the entire range of porosity. Both analytical models, namely Mean Field theory for porous solids and beam theory for cellular solids, and Finite Elements method are used and the corresponding results are compared. For low porosity, Mean Field models yield good predictions. However, when increasing the void concentration and the pores become macroscopically interconnected, only the Differential Method continues to give good estimates. The potential of Mean Field models suitable for highly porous solids to predict the response of cellular materials is also investigated.

We report on the cytogenetic and molecular characterization of a constitutional de novo ring chromosome 22 (r(22)) in 2 unrelated patients with emphasis on different hypotheses proposed to explain the phenotypic variability characterizing this genomic disorder. In both patients, molecular investigations using FISH and array-CGH techniques revealed a 22q terminal deletion involving the 22q13.33 critical region. The size of the deletion was estimated to at least 1.35 Mb in the first proband and to only 300 kb in the second. They both exhibited the major features of r(22) syndrome, but the first patient was more profoundly affected. He had a more severe phenotype, further complicated by behavioral anomalies, autistic-like features with abnormal EEG pattern and brain MRI profile. Haploinsufficiency of the SHANK3 gene, lying in the minimal critical region, is nowadays considered as responsible for most neurobehavioral anomalies. Nevertheless, phenotypic severity and occurrence of additional features in the first patient suggest a potential involvement of one or more specific gene(s) located proximally to SHANK3 (as PLXNB2, PANX2, ALG12 or MLC1), acting either independently of it or by regulating or promoting its expression and thus disrupting its function when deleted.

International audience; The purpose of the present work is to understand physical phenomena o ccurring in roving structures under transverse compression. In order to reach this aim, transverse behavior of prototype rovings featuring a small number of polyamide 6.6 filaments are studied using an experimental device developed in our laboratory. Moreover, the effect of roving characteristics on their transverse compression behavior is examined. The studied characteristics are filament diameter and number, roving twist and tension. It is found that the roving behavior under compression shows plateaus separated by a significant increase of compression force, indicating discontinuous changes in the roving structures. This fact may be attributed to a reorganization of rovings followed by a local slippage between filaments. Transverse properties of rovings are affected by contact-friction inter filaments and the initial filament section fraction. In fact, it is more difficult to compact high-twisted rovings. Rovings with a greater number of filaments require a higher force in order to be compacted. The pre-tension of the rovings has no noticeable effect on their compression behavior

International audience; The purpose of the present work is to understand physical phenomena occurring in roving structure under transverse compression. In order to reach this aim, transverse behavior of prototype rovings featuring a small number of polyamide 6;6 filaments are studied using an experimental device developed in our laboratory. Moreover, the effect of roving characteristics on their transverse compression behavior is examined. The studied characteristics are filament diameter and number, roving twist and tension. it is found tha the roving behavior under compression shows plateaus separated by a significant increase of compression force, indicating discontinuous changes in the roving structure. This fact may be attributed to a reorgganization of roving followed by a local slippage between filaments. Transverse properties of rovings are affected by contact friction inter filaments and the initial filament section fraction. In fact, it is more difficults to compact hight-twisted rovins. Rovings with a greater number of ilaments require a higher force in order to be compacted. The pre-tension of the rovns are no noticeable effect on their compression behavior.

International audience; Current soil water models do not take into account the internal organization of the soil medium and, consequently, ignore the physical interaction between the water film at the surface of solids making the soil structure, and this structure. In that sense they empirically deal with the physical soil properties that are all generated from this soil water – structure interaction. As a result, the thermodynamic state of the soil water medium, which constitutes the local physical conditions, namely the pedo-climate, for biological and geo-chemical processes in soil, is not defined in these models. The omission of soil structure from soil characterization and modeling does not allow for coupling disciplinary models for these processes with soil water models. The objective of the article is to present a soil water structure model, Kamel®, which should be liable to open the deadlocks above-mentioned. This computer model was developed based on a new paradigm in soil physics where the hierarchical soil structure is taken into account allowing for defining its thermodynamic properties. After a review of soil physics principles which forms the basis of the paradigm, we describe the basic relationships and functionality of the model. Kamel® runs with a set of 15 soil input parameters, the pedohydral parameters, which are parameters of the physically-based equations of four soil characteristic curves that can be measured in the laboratory. For cases where some of these parameters are not available, we show how to estimate these parameters from commonly available soil information using published pedotransfer functions. A published field experimental study on the dynamics of the soil moisture profile following a pounding infiltration rainfall event was used as an example to demonstrate soil characterization and Kamel® simulations. The simulated soil moisture profile for a period of 60 days showed very good agreement with experimental field data. Simulations using input data calculated from soil texture and pedotransfer functions were also generated and compared to simulations of the more ideal characterization. The later comparison illustrates how Kamel® can be used and adapt to any case of soil data availability. As physically based model on soil structure, it may be used as a standard reference to evaluate other soil-water models and also pedotransfer functions at a given location or agronomical situation.

Current soil water models do not take into account the internal organization of the soil medium and, a fortiori, the physical interaction between the water film surrounding the solid particles of the soil structure, and the surface charges of this structure. In that sense they empirically deal with the physical soil properties that are all generated from this soil water-structure interaction. As a result, the thermodynamic state of the soil water medium, which constitutes the local physical conditions, namely the pedo-climate, for biological and geo-chemical processes in soil, is not defined in these models. The omission of soil structure from soil characterization and modeling does not allow for coupling disciplinary models for these processes with soil water models. This article presents a soil water structure model, Kamel®, which was developed based on a new paradigm in soil physics where the hierarchical soil structure is taken into account allowing for defining its thermodynamic properties. After a review of soil physics principles which forms the basis of the paradigm, we describe the basic relationships and functionality of the model. Kamel® runs with a set of 15 soil input parameters, the pedohydral parameters, which are parameters of the physically-based equations of four soil characteristic curves that can be measured in the laboratory. For cases where some of these parameters are not available, we show how to estimate these parameters from commonly available soil information using published pedotransfer functions. A published field experimental study on the dynamics of the soil moisture profile following a pounded infiltration rainfall event was used as an example to demonstrate soil characterization and Kamel® simulations. The simulated soil moisture profile for a period of 60 days showed very good agreement with experimental field data. Simulations using input data calculated from soil texture and pedotransfer functions were also generated and compared to simulations of the more ideal characterization. The later comparison illustrates how Kamel® can be used and adapt to any case of soil data availability. As physically based model on soil structure, it may be used as a standard reference to evaluate other soil-water models and also pedotransfer functions at a given location or agronomical situation.

Gene targeting frequencies in Aspergillus niger are often very low and hamper efficient functional genomics in this biotechnologically important fungus. Deletion of the A. niger kusA gene encoding the ortholog of the Ku70 protein in other eukaryotes, dramatically improved homologous integration efficiency and reached more than 80% compared to 7% in the wild-type background, when 500bp homologous flanks were used. Furthermore, the use of the DeltakusA strain resulted in a high frequency of heterokaryon formation (70%) in primary transformants in the case disrupting an essential gene. Deletion of kusA had no obvious effect on the growth of the fungus, but renders the DeltakusA strain 10 times more sensitive to X-ray irradiation and two to three times more sensitive to UV exposure. The highly efficient gene targeting in combination with the A. niger genome sequence allows a systematic approach to generate gene knockouts and will help in improving the capacities of A. niger as producer of commercially interesting proteins and metabolites.