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In the stamping of industrial parts, friction and lubrication play a key role in achieving high quality products and reducing scrap. Especially in the start-up phase of new production runs, transient effects can have a significant impact on the product quality. Before a steady-state production run is established, heating up of tools influence tribological conditions. This influences the performance of the forming operation and, consequently, the quality of the formed product. In the development process of new industrial parts, it is therefore crucial to accurately account for these transient effects in sheet metal forming simulations. This paper presents the modeling of the frictional behavior of two tribological systems as developed within the ASPECT project. The first tribology systems consist of a stainless steel with corresponding drawing oil and tool material. The sheet material of the second tribology system is a hot dip galvanized bake hardened steel. Subsequently, it is shown how temperature affects the frictional behavior of these tribology systems. Finally, generated friction models have been applied to a spare wheel well of Opel. The spare wheel well is modelled using a generally applicable approach to account for transient effects under industrial sheet metal forming process conditions. For varying temperature and tribological conditions, the spare wheel well can show cracks and differences in thinning and draw-in. This emphasizes the strong influence of transient effects on both part quality and the overall production stability.

Moumeni L, Gastebois A, Gillmann L, Papon N, Benia F, Bouchara J-P, Bounechada M. 2021. Investigating the prevalence of Bark beetles of Pinus halepensis in the North East semi-arid region of Algeria. Biodiversitas 22: 2755-2762. Aleppo pine is the most common tree in the semi-arid forests of Algeria. Despite its high resistance to drought and adaptability to all types of soils, the effects of climate change are affecting it directly and indirectly. Stressed trees indeed are subject to bark beetle attacks. In this study, we sampled the bark beetles directly from the affected pine trees. Six species belonging to the Scolytinae subfamily were identified. Tomicus detruens and Orthotomicus erosus were widely spread and present in the three studied forests, where they were found to colonize living trees while Crypturgus numidicus, Crypturgus mediterraneus, Hylurgus ligniperda and Hylurgus micklitzi colonized only dead trees. Together with future identification of the microfungi associated with these xylophagous insects, these data may help to define prevention measures to fight the decline of Aleppo pine forests observed in some parts of Eastern Algeria.

The numerical simulation of multi-strokes sheet metal cold forming is very CPU time consuming especially if all relevant physical phenomena are considered. For a single stroke FE simulation, although the process is cold forming, thermo-mechanical coupling should be taken into account. Moreover, friction between the blank and the tools should be correctly modeled. If such complexity is included for the simulation of a single stroke in cold forming, simulating multi-strokes process and maybe multi-steps cold metallic sheet forming, will be extremely CPU time consuming and even unrealistic to be performed. In this work, the authors propose a speed-up method called “jump in strokes method”, which allows a CPU reduction up to 60%. This method was applied for two industrial use cases: the first one was proposed by Philips representing small parts used in shavers and the second one by Opel representing the production of large panels in automotive industry.

International audience; Cystic fibrosis (CF) is the major genetic inherited disease in Caucasian populations. The respiratory tract of CF patients displays a sticky viscous mucus, which allows for the entrapment of airborne bacteria and fungal spores and provides a suitable environment for growth of microorganisms, including numerous yeast and filamentous fungal species. As a consequence, respiratory infections are the major cause of morbidity and mortality in this clinical context. Although bacteria remain the most common agents of these infections, fungal respiratory infections have emerged as an important cause of disease. Therefore, the International Society for Human and Animal Mycology (ISHAM) has launched a working group on Fungal respiratory infections in Cystic Fibrosis (Fri-CF) in October 2006, which was subsequently approved by the European Confederation of Medical Mycology (ECMM). Meetings of this working group, comprising both clinicians and mycologists involved in the follow-up of CF patients, as well as basic scientists interested in the fungal species involved, provided the opportunity to initiate collaborative works aimed to improve our knowledge on these infections to assist clinicians in patient management. The current review highlights the outcomes of some of these collaborative works in clinical surveillance, pathogenesis and treatment, giving special emphasis to standardization of culture procedures, improvement of species identification methods including the development of nonculture-based diagnostic methods, microbiome studies and identification of new biological markers, and the description of genotyping studies aiming to differentiate transient carriage and chronic colonization of the airways. The review also reports on the breakthrough in sequencing the genomes of the main Scedosporium species as basis for a better understanding of the pathogenic mechanisms of these fungi, and discusses treatment options of infections caused by multidrug resistant microorganisms, such as Scedosporium and Lomentospora species and members of the Rasamsonia argillacea species complex.

The design and control of walking robots is a great issue for researchers (high number of DOFs, coupled phenomena). They could benefit to the biomechanics community as testing beds for bio-inspired...

International audience; Histidine kinases (HKs) are primary sensor proteins that act in cell signaling pathways generically referred to as “two-component systems” (TCSs). TCSs are among the most widely distributed transduction systems used by both prokaryotic and eukaryotic organisms to detect and respond to a broad range of environmental cues. The structure and distribution of HK proteins are now well documented in prokaryotes, but information is still fragmentary for eukaryotes. Here, we have taken advantage of recent genomic resources to explore the structural diversity and the phylogenetic distribution of HKs in the prominent eukaryotic supergroups. Searches of the genomes of 67 eukaryotic species spread evenly throughout the phylogenetic tree of life identified 748 predicted HK proteins. Independent phylogenetic analyses of predicted HK proteins were carried out for each of the major eukaryotic supergroups. This allowed most of the compiled sequences to be categorized into previously described HK groups. Beyond the phylogenetic analysis of eukaryotic HKs, this study revealed some interesting findings: 1) characterization of some previously undescribed eukaryotic HK groups with predicted functions putatively related to physiological traits; 2) discovery of HK groups that were previously believed to be restricted to a single kingdom in additional supergroups, and 3) indications that some evolutionary paths have led to the appearance, transfer, duplication, and loss of HK genes in some phylogenetic lineages. This study provides an unprecedented overview of the structure and distribution of HKs in the Eukaryota and represents a first step toward deciphering the evolution of TCS signaling in living organisms.

Cystic fibrosis (CF) is the major genetic inherited disease in Caucasian populations. The respiratory tract of CF patients displays a sticky viscous mucus, which allows for the entrapment of airborne bacteria and fungal spores and provides a suitable environment for growth of microorganisms, including numerous yeast and filamentous fungal species. As a consequence, respiratory infections are the major cause of morbidity and mortality in this clinical context. Although bacteria remain the most common agents of these infections, fungal respiratory infections have emerged as an important cause of disease. Therefore, the International Society for Human and Animal Mycology (ISHAM) has launched a working group on Fungal respiratory infections in Cystic Fibrosis (Fri-CF) in October 2006, which was subsequently approved by the European Confederation of Medical Mycology (ECMM). Meetings of this working group, comprising both clinicians and mycologists involved in the follow-up of CF patients, as well as basic scientists interested in the fungal species involved, provided the opportunity to initiate collaborative works aimed to improve our knowledge on these infections to assist clinicians in patient management. The current review highlights the outcomes of some of these collaborative works in clinical surveillance, pathogenesis and treatment, giving special emphasis to standardization of culture procedures, improvement of species identification methods including the development of nonculture-based diagnostic methods, microbiome studies and identification of new biological markers, and the description of genotyping studies aiming to differentiate transient carriage and chronic colonization of the airways. The review also reports on the breakthrough in sequencing the genomes of the main Scedosporium species as basis for a better understanding of the pathogenic mechanisms of these fungi, and discusses treatment options of infections caused by multidrug resistant microorganisms, such as Scedosporium and Lomentospora species and members of the Rasamsonia argillacea species complex.

A novel gadolinium and cobalt based aluminide, namely Gd3Co4+xAl12−x (x = 0.50(3)) is shown to crystallize in the hexagonal Gd3Ru4Al12 structure-type (space-group P63/mmc, a = 8.6830(1) A, c = 9.3164(2) A at room temperature). The investigation of its magnetic properties revealed a reversible ferromagnetic ordering at TC ≈ 40 K but expanding in a wide temperature range, potentially due to the geometrical magnetic frustrations expected in this structure-type. The magnetocaloric properties of this intermetallic, determined from both magnetization and specific heat data, are dominated by a maximum entropy variation of −3.28 J kg−1 K−1 at 39(1) K and an adiabatic temperature change of about 1.5 K extending from 20 to 40 K, highlighting some interest for low temperature applications.

The opportunistic fungal pathogen Scedosporium boydii is the most common Scedosporium species in French patients with cystic fibrosis. Here we present the first genome report for S. boydii, providing a resource which may enable the elucidation of the pathogenic mechanisms in this species.

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International audience; Histidine kinases (HKs) are among the most prominent sensing proteins studied in the kingdom Fungi. Their distribution and biological functions in early diverging fungi (EDF), however, remain elusive. We have taken advantage of recent genomic resources to elucidate whether relationships between the occurrence of specific HKs in some EDF and their respective habitat/lifestyle could be established. This led to the unexpected discovery of fungal HKs that share a high degree of similarity with receptors for plant hormones (ethylene and cytokinin). Importantly, these phytohormone receptor homologs are found not only in EDF that behave as plant root symbionts or endophytes but also in EDF species that colonize decaying plant material. We hypothesize that these particular sensing proteins promoted the interaction of EDF with plants, leading to the conquest of land by these ancestral fungi.

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International audience; This study investigated miR-148b as a potential physiological actor of physical inactivity-induced effects in skeletal muscle. By using animal and human protocols , we demonstrated that the early phase of transition toward inactivity was associated with an increase in muscle miR-148b content, which triggered the downregulation of NRAS and ROCK1 target genes. Using human myo-tubes, we demonstrated that overexpression of miR-148b decreased NRAS and ROCK1 protein levels, and PKB phosphorylation and glucose uptake in response to insulin. Increase in muscle miR-148b content might thus participate in the decrease in insulin sensitivity at the whole body level during the transition toward physical inactivity.

Aspergillus fumigatus is the most prevalent thermophilic inhabitants of decaying vegetation and one of the most important human opportunistic fungal pathogens. Like other fungi, A. fumigatus cells are covered by a cell wall, which is both a protective, rigid exoskeleton and a dynamic structure, undergoing constant modification depending on its environment. The cell wall, in the majority of fungi, is composed of polysaccharides, and understanding the biochemical organization and biogenesis of an A. fumigatus cell wall is essential as this envelop is continuously in contact with the environment/host cell and acts as a sieve and reservoir for molecules, such as enzymes and toxins that play an active role during infection. This article is intended to give an overview of the biosynthesis of constituent cell wall polysaccharides and their postsynthetic modification in A. fumigatus, it also discusses the antifungal drugs that affect cell wall polysaccharide biosynthesis.

The Ce–Co–Al ternary phase diagram has been reinvestigated at 973 K by means of powder X-ray diffraction, scanning electron microscopy, energy dispersive spectroscopy and differential thermal analyses. It contains 5 ternary phases (CeCo 2 Al 8 , Ce 2 Co 6 Al 19 , CeCoAl 4 , Ce 3 Co 3 Al 4 and CeCoAl) as well as 7 extensions in the ternary field of pseudo-binaries (CeAl 2 − x Co x with 0 ⩽ x ⩽ 0.18; CeCo 2 − x Al x with 0 ⩽ x ⩽ 0.21; CeCo 3 − y Al y with 0 ⩽ y ⩽ 0.20; Ce 2 Co 7 − x Al x with 0 ⩽ x ⩽ 0.73; Ce 5 Co 19 − y Al y with 0 ⩽ y ⩽ 0.20; CeCo 5 − x Al x with 0 ⩽ x ⩽ 0.71 and Ce 2 Co 17 − y Al y with 0 ⩽ y ⩽ 2.2). Two liquid areas are present at the Al and Ce-rich corners of this isothermal section.

International audience; Several omics technologies are underway worldwide with an aim to unravel the pathophysiology of a complex phenotype such as type 2 diabetes mellitus (T2DM). While recent studies imply a clinically relevant and potential biomarker role of circulatory miRNAs in the etiology of T2DM, there is lack of data on this aspect in Indians-an ethnic population characterized to represent 'Asian Indian phenotype' known to be more prone to develop T2DM and cardiovascular disease than Europeans. We performed global serum miRNA profiling and the validation of candidate miRNAs by qRT-PCR in a cohort of subjects comprised of normal glucose tolerance (NGT), impaired glucose tolerance (IGT) and patients with T2DM. Our study revealed 4 differentially expressed miRNAs (miR-128, miR-130b-3p, miR-374a-5p, miR-423-5p) in subjects with IGT and T2DM patients compared to control subjects. They were positively or negatively correlated to cholesterol levels, HbA1C, HOMA-IR and fasting insulin. Interestingly, circulating level of miR-128 and miR-130b-3p were also altered in serum of diet-induced diabetic mice compared to control animals. Among the altered circulating miRNAs, miR-128 had never been described in previous studies/populations and appeared to be a 'New Lead' in Indians. It was positively correlated with cholesterol both in prediabetic subjects and in diet-induced diabetic mice, suggesting that its increased level might be associated with the development of dyslipedemia associated with T2DM. Our findings imply directionality towards biomarker potential of miRNAs in the prevention/diagnosis/treatment outcomes of diabetes.

Scedosporium boydii is a pathogenic filamentous fungus that causes a wide range of human infections, notably respiratory infections in patients with cystic fibrosis. The development of new therapeutic strategies targeting S. boydii necessitates a better understanding of the physiology of this fungus and the identification of new molecular targets. In this work, we studied the conidium-to-germ tube transition using a variety of techniques including scanning and transmission electron microscopy, atomic force microscopy, two-phase partitioning, microelectrophoresis and cationized ferritin labeling, chemical force spectroscopy, lectin labeling, and nanoLC-MS/MS for cell wall GPI-anchored protein analysis. We demonstrated that the cell wall undergoes structural changes with germination accompanied with a lower hydrophobicity, electrostatic charge and binding capacity to cationized ferritin. Changes during germination also included a higher accessibility of some cell wall polysaccharides to lectins and less CH3/CH3 interactions (hydrophobic adhesion forces mainly due to glycoproteins). We also extracted and identified 20 GPI-anchored proteins from the cell wall of S. boydii, among which one was detected only in the conidial wall extract and 12 only in the mycelial wall extract. The identified sequences belonged to protein families involved in virulence in other fungi like Gelp/Gasp, Crhp, Bglp/Bgtp families and a superoxide dismutase. These results highlighted the cell wall remodeling during germination in S. boydii with the identification of a substantial number of cell wall GPI-anchored conidial or hyphal specific proteins, which provides a basis to investigate the role of these molecules in the host-pathogen interaction and fungal virulence.

Current lifestyle changes, notably sedentary behavior, are associated with chronic diseases, while regular activity improves metabolic functions The purpose of my work is to examine the effects of different level of physical activity, until extreme inactivity on cross-talk mediators, such as adiponectine and microRNAs, and on metabolism, notably in muscle or liver. We demonstrate a significant increase of hepatic markers under severe physical inactivity (60d bed-rest), showing the onset of a development of NASH. Our data support that regular exercise can limit these physical inactivity-induced metabolic alterations. We demonstrate that independently of effects of physical activity and inactivity on fat mass, adiponectin plasma concentrations were negatively related to physical activity level. Our data highlight that variations in total plasma adiponectin with physical activity level are mainly due to changes in HMW adiponectin plasma concentrations, and are unlikely explained by variations in expression of adiponectin in adipose tissue and muscle. We also show an inverse relation between fasting insulin plasma concentrations with both adiponectin receptors, and one of its downstream effector (APPL1) in the muscle, suggesting an improvement of adiponectin muscular sensitivity. During a contrasted and moderate physical activity intervention in human and mice, we show that transition from activity toward inactivity results in muscle miR-148b content increase, leading to muscle metabolism alteration. Our study on miR-148b expression modulation in vitro in human myotubes, show its involvement in insulin signaling pathway in muscle, suggesting that miR-148b accumulation in muscle could participate in the whole body insulin sensitivity degradation, which is a feature of persistent sedentary behavior. Altogether, these results demonstrate that the study of cross-talk actors is crucial to understand the mechanisms involved in active and inactive behaviors, and their effects on health, Les travaux de thèse présentés dans ce manuscrit ont pour but d’étudier les effets de différents niveaux d’activité physique, jusqu’à l’inactivité extrême sur des acteurs du dialogue inter-organe comme l’adiponectine et les microARNs, et sur le métabolisme, notamment dans le muscle ou le foie. Nous démontrons que l’inactivité physique extrême, dans le cadre d’un bedrest de 60 jours, augmente les marqueurs de l’inflammation hépatique, prémices du développement d’une stéato-hépatite non alcoolique. Nos données montrent que des exercices réguliers peuvent limiter les altérations métaboliques induites par l’inactivité physique. Nous montrons, ensuite qu’indépendamment des effets de l’activité et l’inactivité physique sur la masse grasse, les concentrations circulantes d’adiponectine sont inversement associées avec le niveau d’activité physique. Nous montrons notamment que les variations des taux circulants d’adiponectine totale avec le niveau d’activité physique sont principalement dû aux variations de la forme de haut poids moléculaire, et ne sont pas expliquées par des variations d’expression de l’adiponectine dans le tissu adipeux ou musculaire. Nous montrons également une relation inverse entre l’insulinémie plasmatique à jeun et les récepteurs de l’adiponectine, et un de ses effecteurs (APPL1) dans le muscle supportant l’amélioration de la sensibilité à l’adiponectine musculaire. Au cours d’une intervention contrastée et modérée sur le niveau d’activité physique chez l’homme et la souris, nous avons pu montrer que la transition d’un statut actif vers inactif augmentait le niveau d’expression de miR-148b dans le muscle, participant à la dégradation du métabolisme. Notre étude de modulation de l’expression de miR-148b in vitro dans les myotubes humains, montre son implication dans la voie de signalisation de l’insuline, et suggère que l’accumulation de miR-148b dans le tissu musculaire peut participer à l’altération de la sensibilité à l’insuline qui est caractéristique des comportements sédentaires persistants. L’ensemble de ces résultats démontrent que l’étude des acteurs de la signalisation inter-organe est cruciale pour comprendre les mécanismes mis en jeu par les comportements actifs et inactifs, et leurs effets sur la santé

International audience; BACKGROUND:SUN proteins are involved in yeast morphogenesis, but their function is unknown.RESULTS:SUN protein plays a role in the Aspergillus fumigatus morphogenesis. Biochemical properties of recombinant SUN proteins were elucidated.CONCLUSION:Both Candida albicans and Aspergillus fumigatus sun proteins show a β-(1,3)-glucanase activity.SIGNIFICANCE:The mode of action of SUN proteins on β-(1,3)-glucan is unique, new, and original. In yeasts, the family of SUN proteins has been involved in cell wall biogenesis. Here, we report the characterization of SUN proteins in a filamentous fungus, Aspergillus fumigatus. The function of the two A. fumigatus SUN genes was investigated by combining reverse genetics and biochemistry. During conidial swelling and mycelial growth, the expression of AfSUN1 was strongly induced, whereas the expression of AfSUN2 was not detectable. Deletion of AfSUN1 negatively affected hyphal growth and conidiation. A closer examination of the morphological defects revealed swollen hyphae, leaky tips, intrahyphal growth, and double cell wall, suggesting that, like in yeast, AfSun1p is associated with cell wall biogenesis. In contrast to AfSUN1, deletion of AfSUN2 either in the parental strain or in the AfSUN1 single mutant strain did not affect colony and hyphal morphology. Biochemical characterization of the recombinant AfSun1p and Candida albicans Sun41p showed that both proteins had a unique hydrolysis pattern: acting on β-(1,3)-oligomers from dimer up to insoluble β-(1,3)-glucan. Referring to the CAZy database, it is clear that fungal SUN proteins represent a new family of glucan hydrolases (GH132) and play an important morphogenetic role in fungal cell wall biogenesis and septation.

MgtC is important for the survival of several bacterial pathogens in macrophages and for growth under magnesium limitation. Among eukaryotes, a gene homologous to mgtC was found only in the pathogenic fungus Aspergillus fumigatus . Our data show that the A. fumigatus MgtC (AfuMgtC) protein does not have the same function as the bacterial MgtC proteins.

The β(1-3)glucanosyltransferase GEL family of Aspergillus fumigatus contains 7 genes, among which only 3 are expressed during mycelial growth. The role of the GEL4 gene was investigated in this study. Like the other Gelps, it encodes a glycosylphosphatidylinositol (GPI)-anchored protein. In contrast to the other β(1-3)glucanosyltransferases analyzed to date, it is essential for this fungal species.

International audience; A new HPLC method was developed to separate linear from beta(1-6)-branched beta(1-3)-glucooligosaccharides. This methodology has permitted the isolation of the first fungal beta(1-6)/beta(1-3)-glucan branching transglycosidase using a cell wall autolysate of Aspergillus fumigatus (Af). The encoding gene, AfBGT2 is an ortholog of AfBGT1, another transglycosidase of A. fumigatus previously analyzed (Mouyna, I., Hartland, R. P., Fontaine, T., Diaquin, M., Simenel, C., Delepierre, M., Henrissat, B., and Latgé, J. P. (1998) Microbiology 144, 3171-3180). Both enzymes release laminaribiose from the reducing end of a beta(1-3)-linked oligosaccharide and transfer the remaining chain to another molecule of the original substrate. The AfBgt1p transfer occurs at C-6 of the non-reducing end group of the acceptor, creating a kinked beta(1-3;1-6) linear molecule. The AfBgt2p transfer takes place at the C-6 of an internal group of the acceptor, resulting in a beta(1-3)-linked product with a beta(1-6)-linked side branch. The single Afbgt2 mutant and the double Afbgt1/Afbgt2 mutant in A. fumigatus did not display any cell wall phenotype showing that these activities were not responsible for the construction of the branched beta(1-3)-glucans of the cell wall.

This facility has been designed to carry out cryogenic RF quality factor (QRF) measurements, cold tuner tests, high order modes coupler tests, main coupler tests and full RF tests of superconducting cavities under real accelerator conditions (pulse mode, feedback loops, etc). The cryostat is built to receive one horizontally positioned cavity equipped with its helium vessel, its tuner and various RF couplers. The maximum heat load is ≈ 58 W (2.5 g/s) at 2 K for high power peak processing and ≈ 6 W (0.25 g/s) under normal conditions. QRF will be obtained from heat load measurements by LHe level variation and gas flow measurement at known temperature and pressure. The calibration is given by a DC electrical heater. The paper describes the design and the preliminary results of cryogenic performance tests of the cryostat itself.

We describe the capture cavity cryostat, for the Tesla Test Facility at DESY in Hamburg, which was designed and is presently under assembly in France. We also discuss the construction of an ancillary feed box which is required for a preliminary cryogenic test prior to delivery.