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6. Déflecteur optique pour la réalisation d'un convertisseur analogique-numérique à grande bande passante Principe de fonctionnement du convertisseur analogique-numérique tout optique

Author

Ferchichi, K., P-V, Dugué, Flavie Braud, Halbwax, M., Vilcot, J. P., Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520 (IEMN), Centrale Lille-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF)-JUNIA (JUNIA), Optoélectronique - IEMN (OPTO - IEMN), Centrale Lille-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF)-JUNIA (JUNIA)-Centrale Lille-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF)-JUNIA (JUNIA), Institut d'Électronique et des Technologies du numéRique (IETR), Université de Nantes (UN)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Université de Rennes (UNIV-RENNES)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), Centrale de Micro Nano Fabrication - IEMN (CMNF - IEMN), Renatech Network, ANR-17-ASTR-0004,ADC Poly,Déflecteur à base d'un guide optique à fuite en polymère en vue de la réalisation d'un convertisseur analogique-numérique tout-optique à plus de 40 Giga échantillons par seconde(2017), Université catholique de Lille (UCL)-Université catholique de Lille (UCL), INSA Institut National des Sciences Appliquées Hauts-de-France (INSA Hauts-De-France), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520 (IEMN), Université catholique de Lille (UCL)-Université catholique de Lille (UCL)-Centrale Lille-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF)-JUNIA (JUNIA), Université de Nantes (UN)-Université de Rennes (UR)-Institut National des Sciences Appliquées - Rennes (INSA Rennes), Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), and Nantes Université (NU)-Université de Rennes 1 (UR1)

Subjects
[SPI]Engineering Sciences [physics]
Abstract

National audience; Un concept original de convertisseur analogique-numérique tout optique à grande bande passante repose sur l’utilisation d’un composant d’optique intégrée spécifique consistant en un déflecteur électro-optique hors-plan 1. Celui-ci convertit l’amplitude d’une tension appliquée à ces bornes en une déflexion proportionnelle du faisceau optique défléchi. La technologie retenue pour la fabrication de ce composant utilise les matériaux polymères. Nous présentons ici la mise en place de cette technologie ainsi que son application à la réalisation du déflecteur. De premiers résultats de propagation optique au sein d’un guide ainsi réalisé sont aussi présentés.

Published
2021

13. Kinetics of Ge growth at low temperature on Si(001) by ultrahigh vacuum chemical vapor deposition

Author

Halbwax, M., Bouchier, D., Yam V., Debarre, D., Nguyen, Lam H., Y. Zheng, Rosner, P., Benamara, M., Strunk, H.P., and Clerc, C.

Subjects
Silicon -- Chemical properties, Germanium -- Chemical properties, Chemical vapor deposition -- Research, Electrons -- Diffraction, Electrons -- Research, Physics
Abstract

A study investigates the growth of germanium at low temperature by ultrahigh vacuum chemical vapor deposition on Si(001) by reflection high-energy electron diffraction. A complementarily checking of the observations of these studies is done by Rutherford backscattering spectrometry, transmission electron microscopy, and x-ray diffraction experiments.

Published
2005

18. Passivation Al2O3 par ALD sur p-Si Cz

Author

PAWLIK, M., Vilcot, J.P., Halbwax, M., GAUTHIER, M., Le Quang, N., Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520 (IEMN), Centrale Lille-Institut supérieur de l'électronique et du numérique (ISEN)-Université de Valenciennes et du Hainaut-Cambrésis (UVHC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF), PHOTOWATT, EDF ENR PWT, and EDF (EDF)

Published
2013

19. The PROTERRA project : advanced processes using alternative raw materials for an economic production of high efficiency solar cells and modules

Author

Le Quang, N., Gauthier, M., Gerard, M., Williatte, S., Rambaud, A.M., Goaer, G., Lemiti, M., Blanc-Pélissier, D., Focsa, A., Fourmond, E., Conte, D., Moyroud, J., Vilcot, J.-P., Pawlik, M., Halbwax, M., Auriac, N., Monna, R., Gall, S., Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520 (IEMN), and Centrale Lille-Institut supérieur de l'électronique et du numérique (ISEN)-Université de Valenciennes et du Hainaut-Cambrésis (UVHC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF)

Subjects
WAFER-BASED SILICON SOLAR CELLS AND MATERIALS TECHNOLOGY, 02 engineering and technology, 010402 general chemistry, 021001 nanoscience & nanotechnology, 0210 nano-technology, 7. Clean energy, 01 natural sciences, 0104 chemical sciences, Silicon Solar Cell Improvements
Abstract

28th European Photovoltaic Solar Energy Conference and Exhibition; 1952-1956, The PROTERRA project develops new processes based on techniques that could be transferred into industrial production of high efficiency and low cost c-Si solar cells and modules. Significant solar cell conversion efficiency improvement and reduction of their production cost are expected using a new cell structure favoring both front and rear passivation associated with self-aligned metallization. To achieve this structure, it is essential to incorporate innovative concepts applicable to most key steps of solar cell manufacturing as selective emitter, rear side passivation by dielectric layers, electrolytic metallization, local BSF and rear contacts. The in-line silicone encapsulation process which reduces the absorption of photons in the UV is used for module preparation with the target to ameliorate module performance. Numerous tests with a wide series of crystalline silicon solar cells have been underway in order to release necessary data for process evaluations. Some interesting experimental results have been obtained in an attempt to identify the best candidates to replace standard processes for c-Si solar cell and module production.

Published
2013
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20. Bonobos fall within the genomic variation of chimpanzees

Author

Fischer, A., Prüfer, K., Good, J., Halbwax, M., Wiebe, V., André, C., Atencia, R., Mugisha, L., Ptak, S., and Pääbo, S.

Subjects
Male, Evolutionary Genetics, Evolutionary Processes, Pan troglodytes, Speciation, Science, Animal Phylogenetics, DNA, Mitochondrial, Evolution, Molecular, Genetics, Animals, Humans, Evolutionary Systematics, Biology, Phylogeny, Taxonomy, Evolutionary Biology, Genome, Population Biology, Genetic Drift, Genetic Variation, Genomic Evolution, Sequence Analysis, DNA, Pan paniscus, Phylogenetics, Mammalogy, Animal Taxonomy, Neutral Theory, Genetic Polymorphism, Medicine, Animal Genetics, Zoology, Population Genetics, Research Article
Abstract

To gain insight into the patterns of genetic variation and evolutionary relationships within and between bonobos and chimpanzees, we sequenced 150,000 base pairs of nuclear DNA divided among 15 autosomal regions as well as the complete mitochondrial genomes from 20 bonobos and 58 chimpanzees. Except for western chimpanzees, we found poor genetic separation of chimpanzees based on sample locality. In contrast, bonobos consistently cluster together but fall as a group within the variation of chimpanzees for many of the regions. Thus, while chimpanzees retain genomic variation that predates bonobo-chimpanzee speciation, extensive lineage sorting has occurred within bonobos such that much of their genome traces its ancestry back to a single common ancestor that postdates their origin as a group separate from chimpanzees.

Published
2011

21. Measurement of microwave permittivity of polymer meterials for high speed optical modulator design

Author

Philippe Auguste, K.R., Legier, Jean-François, Paleczny, Erick, Halbwax, M., Mahe, H., Fontadieu, L., Vilcot, J.P., Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520 (IEMN), and Centrale Lille-Institut supérieur de l'électronique et du numérique (ISEN)-Université de Valenciennes et du Hainaut-Cambrésis (UVHC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF)

Published
2010

22. Recent progress in high-speed silicon-based optical modulators [Invited paper]

Author

Marris-Morini, D., Vivien, L., Rasigade, G., Fedeli, J.M., Cassan, E., Le Roux, Xavier, Crozat, P., Maine, S., Lupu, A., Lyan, P., Rivallin, P., Halbwax, M., Laval, S., Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520 (IEMN), and Centrale Lille-Institut supérieur de l'électronique et du numérique (ISEN)-Université de Valenciennes et du Hainaut-Cambrésis (UVHC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF)

Published
2009
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23. Theoretical and experimental study of the antireflection optical properties of TiO2 thin films elaborated by sol-gel method

Author

Arabi, N.H., El Hamzaoui, H., Iratni, A., Capoen, B., Halbwax, M., Vilcot, J.P., Bouazaoui, M., Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520 (IEMN), and Centrale Lille-Institut supérieur de l'électronique et du numérique (ISEN)-Université de Valenciennes et du Hainaut-Cambrésis (UVHC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF)

Published
2009

24. Microstructuration of Silicon Surfaces Using Nanoporous Gold Electrodes

Author

Torralba Penalver, Halbwax, M., El Assimi, T., Magnin, V., Harari, J., J-P, Vilcot, Sylvain Le Gall, Raphaël Lachaume, Cachet-Vivier, C., Stéphane Bastide, LE GALL, Sylvain, Appel à projets générique - Structuration de surface du silicium par un procédé de gravure par contact utilisant des électrodes métalliques - - PATTERN2014 - ANR-14-CE07-0005 - Appel à projets générique - VALID, Institut de Chimie et des Matériaux Paris-Est (ICMPE), Institut de Chimie du CNRS (INC)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS), Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520 (IEMN), Centrale Lille-Institut supérieur de l'électronique et du numérique (ISEN)-Université de Valenciennes et du Hainaut-Cambrésis (UVHC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF), Laboratoire Génie électrique et électronique de Paris (GeePs), Université Paris-Sud - Paris 11 (UP11)-Université Pierre et Marie Curie - Paris 6 (UPMC)-CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), ISE, and ANR-14-CE07-0005,PATTERN,Structuration de surface du silicium par un procédé de gravure par contact utilisant des électrodes métalliques(2014)

Subjects
[CHIM.ANAL] Chemical Sciences/Analytical chemistry, [CHIM.ANAL]Chemical Sciences/Analytical chemistry, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], [CHIM.CATA] Chemical Sciences/Catalysis, [CHIM.CATA]Chemical Sciences/Catalysis, [PHYS.COND.CM-MS] Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci]
Abstract

International audience; Etching is a key process in the fabrication of silicon (Si) microstructures that are essential for several component families used in microelectronics, photonics and photovoltaics, among others. A large variety of microstructuring technologies exists nowadays (e.g. wet/dry etchings based on photo/electron beam lithography patterning). Their remarkable efficacy comes at the expense of several lithography (masking) /etching steps that are not suitable for all industries, i.e. when reduced cost and manufacturing time are key aspects (e.g. Si solar cells manufacturing). Hence, the development of a maskless technique with direct imprinting of patterns would dramatically simplify the fabrication process. However, eliminating the use of masks and move towards micromachining techniques has turned to be extremely challenging. Only a few achievements in the field of (electro)chemistry have been reported in the literature [1-4]. The most recent development is an electrochemical version of the metal assisted chemical etching method used to produce high aspect ratio nanostructures: a noble metal electrode is put in contact with a Si sample in a HF solution and polarized against a counter electrode; in the contacted areas the metal plays the role of etching tool by oxidizing/dissolving Si atoms [2,3]. The major problem encountered with this configuration lies in the intimate Si/metal contact, which hinders electrolyte supply over macroscopic distances. Hence, etching is very slow, starting from the edge of the metal tool and progressing laterally. An efficient pattern transfer has been recently demonstrated in the case of porous Si etching with a gold coated stamp, the porous Si network allowing the electrolyte to reach the Si/Au interface [4]. In this work, we present a new strategy to achieve pattern transfer into Si by a single step electrochemical (EC) contact etching with large dimension metal tools, as schemed in Figure 1a. Figure 1. a) Scheme of the electrochemical contact etching process; b, c) optical and SEM images of a n-type (100) Si surface after imprinting a pattern of inverted pyramids with d) a nanoporous Au electrode. The problematic diffusion of the electrolyte is solved by using for the first time nanoporous metal electrodes, which give access for the electrolyte to the whole Si/metal interface. Thus, etching is achieved with a priori no restriction on the dimensions of the treated surfaces. Our first results demonstrate the transfer of a well-defined array of square inverted pyramids over a treated area of approximately 1 mm 2 (Figure 1b and 1c) in a single step and without any prior lithography or masking process of the substrate. The etched pyramids are not aligned with the [001] and [010] directions of the (100) oriented sample (21° off) which clearly indicate that the pattern transfer is independent of the crystallographic orientation. This is a proof of concept for EC contact etching with nanoporous metal imprints, with a high potential for Si surface texturization (e.g. solar cells) [5].

Published
2004

31. Femtosecond laser for black silicon and photovoltaic cells

Author

Sarnet, T., primary, Halbwax, M., additional, Torres, R., additional, Delaporte, P., additional, Sentis, M., additional, Martinuzzi, S., additional, Vervisch, V., additional, Torregrosa, F., additional, Etienne, H., additional, Roux, L., additional, and Bastide, S., additional

Published
2008
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32. Black silicon recent improvements for photovoltaic cells

Author

Sarnet, T., primary, Torres, R., additional, Vervisch, V., additional, Delaporte, P., additional, Sentis, M., additional, Halbwax, M., additional, Ferreira, J., additional, Barakel, D., additional, Pasquinelli, M., additional, Martinuzzi, S., additional, Escoubas, L., additional, Torregrosa, F., additional, Etienne, H., additional, and Roux, L., additional

Published
2008
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39. Epitaxial growth of Ge on a thin SiO2 layer by ultrahigh vacuum chemical vapor deposition

Author

Halbwax, M., Renard, C., Cammilleri, D., Yam, V., Fossard, F., Bouchier, D., Zheng, Y., and Rzepka, E.

Subjects
*CHEMICAL vapor deposition, *EPITAXY, *GERMANIUM, *SCANNING electron microscopy
Abstract

Abstract: In this work, the growth of germanium by ultrahigh vacuum chemical vapor deposition on a 0.6nm thick SiO2 layer formed on Si(001) is investigated by in situ reflection high-energy electron diffraction, high-resolution transmission electron microscopy, scanning electron microscopy, X-ray diffraction and micro-Raman spectroscopy. Because Ge does not grow from germane on SiO2, nucleation sites were created by exposure of the surface to SiH4 at 650°C prior to the Ge deposition, which is initiated at 600°C. The first stage of Ge growth proceeds via the formation of dots that exhibit the same crystalline orientation as the Si substrate. They are assumed to grow from small apertures opened in the silica layer due to the reduction of SiO2 by Si. For further deposition time, {111}- and {113}-facetted Ge crystals are formed and the growth remains monocrystalline. The so-formed Ge crystals are found to be completely relaxed and contain some emerging defects, identified as stacking faults. No misfit or threading dislocations are observed. Consequently, the interface between Ge and the SiO2 layer remains perfectly sharp and free of defects. This relaxation without misfit dislocation is due to SiO2 layer which acts as a buffer layer that prevents the Si substrate from imposing its lattice parameter on the Ge crystal. [Copyright &y& Elsevier]

Published
2007
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40. Ge growth over thin SiO2 by UHV–CVD for MOSFET applications

Author

Renard, C., Halbwax, M., Cammilleri, D., Fossard, F., Yam, V., Bouchier, D., and Zheng, Y.

Subjects
*GERMANIUM crystals, *CHEMICAL vapor deposition, *SILICA, *METAL oxide semiconductor field-effect transistors, *REFLECTION high energy electron diffraction, *SCANNING electron microscopy, *TRANSMISSION electron microscopy, *SILICON alloys
Abstract

Abstract: The growth of germanium by ultra high vacuum–chemical vapour deposition (UHV–CVD) on a thin SiO2 layer (0.6 nm) formed on Si(001) was investigated by real-time reflection high energy electron diffraction (RHEED), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). It was observed that the growth of Ge at 600 °C on a 2 monolayers thick SiO2 (0.6 nm) film remains perfectly coherent with the Si (001) substrate. The mechanism of reduction of SiO2 is also discussed for higher Ge deposition temperatures. It was found to involve both Si from the substrate and Ge from the gas phase. [Copyright &y& Elsevier]

Published
2008
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41. High Efficiency Process for Industrial Manufacturing of p-Type Crystalline Silicon Solar Cells Developed in the Frame of PROTERRA Project

Author

Le Quang, N., Gall, S., Monna, R., Gauthier, M., Gerard, M., Williatte, S., Rambaud, A.M., Goaer, G., Lemiti, M., Blanc-Pélissier, D., Conte, D., Moyroud, J., Vilcot, J.-P., Pawlik, M., and Halbwax, M.

Subjects
WAFER-BASED SILICON SOLAR CELLS AND MATERIALS TECHNOLOGY, 7. Clean energy, Silicon Solar Cell Improvements
Abstract

29th European Photovoltaic Solar Energy Conference and Exhibition; 1328-1332, New advanced processes have been developed in the frame of the French National PROTERRA Project based on techniques that could be transferred into industrial production of high efficiency and low cost c-Si solar cells and modules. Significant solar cell conversion efficiency improvement was expected using a new cell architecture based on PERC concept (Passivated Emitter and Rear Cell) favoring both front and rear surface passivation. To perform this structure, it is essential to integrate innovative concepts developed on technology platforms of research partners to principal steps of industrial solar cell manufacturing at EDF ENR PWT as selective or homogeneous high-sheet-resistance emitter, advanced front side metallization, rear surface passivation by dielectric, localized BSF and localized back contact. The passivation effects of the dielectric layers were studied in the function of their physicochemical properties and applied thermal treatments. The comparison of different laser sources allowed defining the optimum conditions for the ablation of dielectric layers while limiting induced damages in the underlying silicon substrate. Different aluminum screen printing pastes were also evaluated using different contact configurations for their ability to form an effective localized BSF and a good rear side contact while preserving the high quality of passivation in non-ablated regions. The different methods used to form the front contact as screen printing and electrochemical deposition were evaluated. The implementation of selected technological bricks in a complete manufacturing process of solar cells on p-type crystalline silicon substrates of industrial size 156mm x 156mm yielded a high average conversion efficiency of 19.5 % demonstrating an absolute gain of +0.8 % compared to standard full area Al-BSF process.

42. Femtosecond laser texturization for improvement of photovoltaic cells: Black silicon

Author

Torres, R., Vervisch, V., Halbwax, M., Sarnet, T., Delaporte, P., Sentis, M., Ferreira, J., Barakel, D., Stephane Bastide, Torregrosa, F., Etienne, H., Roux, L., Laboratoire Lasers, Plasmas et Procédés photoniques (LP3), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520 (IEMN), Centrale Lille-Institut supérieur de l'électronique et du numérique (ISEN)-Université de Valenciennes et du Hainaut-Cambrésis (UVHC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF), Optoélectronique - IEMN (OPTO - IEMN), Centrale Lille-Institut supérieur de l'électronique et du numérique (ISEN)-Université de Valenciennes et du Hainaut-Cambrésis (UVHC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF)-Centrale Lille-Institut supérieur de l'électronique et du numérique (ISEN)-Université de Valenciennes et du Hainaut-Cambrésis (UVHC)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)-Université Polytechnique Hauts-de-France (UPHF), Institut des Matériaux, de Microélectronique et des Nanosciences de Provence (IM2NP), Aix Marseille Université (AMU)-Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS), IBS, ibs company, Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU), and Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU)

Subjects
photovoltaics, femtosecond laser, black silicon, [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci], ComputingMilieux_MISCELLANEOUS, texturation
Abstract

International audience

47. Addressing the illegal wildlife trade in the European Union as a public health issue to draw decision makers attention.

Author

Halbwax M

Abstract

The European Union is one of the most important markets for the trafficking of endangered species and a major transit point for illegal wildlife trade. The latter is not only one of the most important anthropogenic drivers of biodiversity loss, it also represents a growing risk for public health. Indeed, wildlife trade exposes humans to a plethora of severe emerging infectious diseases, some of which have contributed to the most dramatic global pandemics humankind has endured. Illegal wildlife trade is often considered as a problem of developing countries but it is first and foremost an international global business with a trade flow from developing to developed countries. The devastating effects of the ongoing SARS-CoV-2 outbreak should thus be an unassailable argument for European decision makers to change paradigm. Rather than deploying efforts and money to combat novel pathogens, mitigating the risk of spreading emerging infectious diseases should be addressed and be part of any sustainable socioeconomic development plan. Stricter control procedures at borders and policies should be enforced. Additionally, strengthening research in wildlife forensic science and developing a network of forensic laboratories should be the cornerstone of the European Union plan to tackle the illegal wildlife trade. Such proactive approach, that should further figure in the EU-Wildlife Action Plan, could produce a win-win situation: the curb of illegal wildlife trade would subsequently diminish the likelihood of importing new zoonotic diseases in the European Union., Competing Interests: The author declares that he has no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2020 Elsevier Ltd. All rights reserved.)

Published
2020
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48. A New Species of Sucking Louse from the Mandrill from Gabon with a Review of Host Associations and Geographical Distributions, and Identification Keys to Members of the Genus pedicinus (Phthiraptera: Anoplura: Pedicinidae).

Author

Durden LA, Kessler SE, Boundenga L, Ngoubangoye B, Tsoumbou TA, Moussadji-Kinga CI, Halbwax M, Setchell JM, Nichols J, and Greiman SE

Subjects
Animals, Anoplura anatomy & histology, Anoplura genetics, Anoplura physiology, DNA chemistry, DNA isolation & purification, Female, Gabon epidemiology, Lice Infestations epidemiology, Lice Infestations parasitology, Male, Monkey Diseases epidemiology, Sequence Alignment veterinary, Sequence Analysis, DNA veterinary, Anoplura classification, Lice Infestations veterinary, Mandrillus parasitology, Monkey Diseases parasitology
Abstract

Members of the sucking louse genus Pedicinus are ectoparasites of cercopithecid primates in Africa, Asia, and Gibraltar. Pedicinus gabonensis n. sp. is described on the basis of adult male and female specimens collected from the mandrill (Mandrillus sphinx) in Gabon. The new species is compared morphologically with other members of the genus Pedicinus, and a nuclear elongation factor 1 alpha gene sequence is provided. Host associations and geographical distributions of the 18 previously recognized species of the genus and of P. gabonensis n. sp. are reviewed. Updated identification keys are provided for males and females of all known valid species of Pedicinus., (© American Society of Parasitologists 2020.)

Published
2020
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49. 3D Patterning of Si by Contact Etching With Nanoporous Metals.

Author

Bastide S, Torralba E, Halbwax M, Le Gall S, Mpogui E, Cachet-Vivier C, Magnin V, Harari J, Yarekha D, and Vilcot JP

Abstract

Nanoporous gold and platinum electrodes are used to pattern n-type silicon by contact etching at the macroscopic scale. This type of electrode has the advantage of forming nanocontacts between silicon, the metal and the electrolyte as in classical metal assisted chemical etching while ensuring electrolyte transport to and from the interface through the electrode. Nanoporous gold electrodes with two types of nanostructures, fine and coarse (average ligament widths of ~30 and 100 nm, respectively) have been elaborated and tested. Patterns consisting in networks of square-based pyramids (10 × 10 μm 2 base × 7 μm height) and U-shaped lines (2, 5, and 10 μm width × 10 μm height × 4 μm interspacing) are imprinted by both electrochemical and chemical (HF-H 2 O 2 ) contact etching. A complete pattern transfer of pyramids is achieved with coarse nanoporous gold in both contact etching modes, at a rate of ~0.35 μm min -1 . Under the same etching conditions, U-shaped line were only partially imprinted. The surface state after imprinting presents various defects such as craters, pores or porous silicon. Small walls are sometimes obtained due to imprinting of the details of the coarse gold nanostructure. We establish that np-Au electrodes can be turned into "np-Pt" electrodes by simply sputtering a thin platinum layer (5 nm) on the etching (catalytic) side of the electrode. Imprinting with np Au/Pt slightly improves the pattern transfer resolution. 2D numerical simulations of the valence band modulation at the Au/Si/electrolyte interfaces are carried out to explain the localized aspect of contact etching of n-type silicon with gold and platinum and the different surface state obtained after patterning. They show that n-type silicon in contact with gold or platinum is in inversion regime, with holes under the metal (within 3 nm). Etching under moderate anodic polarization corresponds to a quasi 2D hole transfer over a few nanometers in the inversion layer between adjacent metal and electrolyte contacts and is therefore very localized around metal contacts.

Published
2019
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50. Significant differentiation in the apolipoprotein(a)/lipoprotein(a) trait between chimpanzees from Western and Central Africa.

Author

Noureen A, Ronke C, Khalifa M, Halbwax M, Fischer A, André C, Atencia R, Garriga R, Mugisha L, Ceglarek U, Thiery J, Utermann G, and Schmidt K

Subjects
Africa, Central, Animals, Congo, Gabon, Humans, Sierra Leone, Apoprotein(a) genetics, Lipoprotein(a) genetics, Pan troglodytes genetics
Abstract

Elevated Lipoprotein(a) (Lp(a)) plasma concentrations are a risk factor for cardiovascular disease in humans, largely controlled by the LPA gene encoding apolipoprotein(a) (apo(a)). Lp(a) is composed of low-density lipoprotein (LDL) and apo(a) and restricted to Catarrhini. A variable number of kringle IV (KIV) domains in LPA lead to a size polymorphism of apo(a) that is inversely correlated with Lp(a) concentrations. Smaller apo(a) isoforms and higher Lp(a) levels in central chimpanzees (Pan troglodytes troglodytes [PTT]) compared to humans from Europe had been reported. We studied apo(a) isoforms and Lp(a) concentrations in 75 western (Pan troglodytes verus [PTV]) and 112 central chimpanzees, and 12 bonobos (Pan paniscus [PPA]), all wild born and living in sanctuaries in Sierra Leone, Republic of the Congo, and DR Congo, respectively, and 116 humans from Gabon. Lp(a) levels were severalfold higher in western than in central chimpanzees (181.0 ± 6.7 mg/dl vs. 56.5 ± 4.3 mg/dl), whereas bonobos showed intermediate levels (134.8 ± 33.4 mg/dl). Apo(a) isoform sizes differed significantly between subspecies (means 20.9 ± 2.2, 22.9 ± 4.4, and 23.8 ± 3.8 KIV repeats in PTV, PTT, and PPA, respectively). However, far higher isoform-associated Lp(a) concentrations for all isoform sizes in western chimpanzees offered the main explanation for the higher overall Lp(a) levels in this subspecies. Human Lp(a) concentrations (mean 47.9 ± 2.8 mg/dl) were similar to those in central chimpanzees despite larger isoforms (mean 27.1 ± 4.9 KIV). Lp(a) and LDL, apoB-100, and total cholesterol levels only correlated in PTV. This remarkable differentiation between chimpanzees from different African habitats and the trait's similarity in humans and chimpanzees from Central Africa poses the question of a possible impact of an environmental factor that has shaped the genetic architecture of LPA. Overall, studies on the cholesterol-containing particles of Lp(a) and LDL in chimpanzees should consider differentiation between subspecies., (© 2017 Wiley Periodicals, Inc.)

Published
2017
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