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Vapor and Pressure Sensors Based on Cellulose Nanofibers and Carbon Nanotubes Aerogel with Thermoelectric Properties

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Journal of Renewable Materials 2018年第3期6卷 277-287页

作者： Rajendran Muthuraj Abhishek Sachan Mickael Castro jean-francois Feller Bastien Seantier Yves Grohens Dupuy de Lôme Research Institute(IRDL) FRE CNRS 3744University of Southern BrittanyRue de Saint Maudé56321 Lorient CedexFrance

In this work,thermally insulating and electrically conductive aerogels were prepared from cellulose nanofibers(CNF)and carbon nanotubes(CNTs)by environmentally friendly freeze-drying *** thermal conductivity of neat CNF aerogel is 24 mW/(m・K)with a density of 0.025 g/*** the addition of CNTs into CNF aerogel,the electrical conductivity was significantly increased while the thermal conductivity was increased to 38 mW/(m・K).Due to these interesting properties,the Seebeck coefficient and the figure of merit(ZT)of the CNF/CNTs aerogels were measured and showed that CNF/CNTs aerogel thermoelectric properties can be *** compressibility and electrical resistance of the CNF/CNTs aerogel highlighted its pressure-responsive property.A set of volatile organic compounds(VOCs)were exposed to aerogels to monitor the resistance *** CNF/CNTs aerogel showed high sensitivity and good response to both nonpolar and polar vapors due to the absorption by both CNF and CNTs *** prepared CNF/CNTs aerogel is therefore a good candidate for thermal insulation,thermoelectric material,VOCs sensing,and pressure-sensing applications.

关键词： CNF/CNTs aerogel thermal conductivity pressure sensing thermoelectric materials VOCs sensing

Synergistic control of sex hormones by 17β-HSD type 7: a novel target for estrogen-dependent breast cancer

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分子细胞生物学报:英文版 2015年第6期7卷 568-579页

作者： Xiaoqiang Wang Catherine Gérard jean-francois Thériault Donald Poirier Charles J.Doillon Sheng-Xiang Lin Laboratory of Molecular Endocrinology and Oncology Centre Hospitalier Universitaire de Québec Research Center(CHULCHU)and Laval UniversityQuébec CityQuebecG1V4G2Canada

17β-hydroxysteroid dehydrogenase(17β-HSD)type 1 is known as a critical target to block the final step of estrogen production in estrogen-dependent breast *** confirmation of the role of dyhydroxytestosterone(DHT)in counteracting estrogeninduced cell growth prompted us to study the reductive 17β-HSD type 7(17β-HSD7),which activates estrone while markedly *** role ofDHTin breast cancer cell proliferation isdemonstratedby its independent suppression of cell growthin the presence of a physiological concentration of estradiol(E2).Moreover,an integral analysis of a large number of clinical samples in Oncomine datasets demonstrated the overexpression of 17β-HSD7 in breast *** of 17β-HSD7 in breast cancer cells resulted in a lower level of E2 and a higher level of DHT,successively induced regulation of cyclinD1,p21,Bcl-2,and Bik,consequently arrested cell cycle in the G0/G1 phase,and triggered apoptosis and auto-downregulation feedback of the *** inhibition led to significant shrinkage of xenograft tumors with decreased cancer cell density and reduced 17β-HSD7 *** plasma E2 and elevated plasma DHT levels were also ***,the dual functional 17β-HSD7 is proposed as a novel target for estrogen-dependent breast cancer by regulating the balance of E2 *** aconceptual advance on the general belief that the major role of this enzyme is in cholesterol metabolism.

关键词： 17β-hydroxysteroid dehydrogenase type 7 breast cancer xenograft tumor steroid enzyme inhibition

A new friedelane triterpenoid and saponin with moderate antimicrobial activity from the stems of Drypetes laciniata

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Chinese Chemical Letters 2011年第2期22卷 171-174页

作者： Simone Veronique Fannang Victor Kuete Celine Mbazoa Djama Marlise Diane J.Dongfack jean Duplex Wansi francois Tillequin Elisabeth Seguin Elizabeth Chosson jean Wandji Laboratoire de Synthese et de Produits Naturels Departement de Chimie Organique de l'Universite de Yaounde-1Faculte des SciencesP.O.Box 812 YaoundeCameroon Department of Biochemistry University of DschangFaculty of ScienceP.O.Box 67 DschangCameroon Laboratoire de Pharmacognosie de l'Universite Paris Descartes UMR/CNRS No.8638Faculte des Sciences Biologiques et Pharmaceutiques4-Avenue de l'Observatoire75006 ParisFrance Department of Chemistry University of DoualaFaculty of ScienceP.O.Box 24157 DoualaCameroon Laboratoire de Pharmacognosie UFR de Medecine Pharmacie Rouen22-Bld Gambetta76183 Rouen Cedex 1France

A new friedelane-type triterpene named 3β-hydroxyfriedelane-7,12,22-trione,as well as nine known compounds were isolated from the whole stems of Drypetes laciniata Hutch.（Euphorbiaceae）.Their structures were established on the basis of spectroscopic *** new triterpene derivative and a known saponin were tested for antimicrobial and antifungal activities and they appeared to be moderate active.

关键词： Drypetes laciniata Euphorbiaceae Stem Friedelane-type triterpenoid Antimicrobial activity

The Restoration of Kidane Mehret Church in Sen＇afe

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Journal of Sociology Study 2016年第11期6卷 713-720页

作者： jean-francois Breton The French National Center for Scientific Research CCNRS) France

A Follow-Up on Projection Theory: Theorems and Group Action

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Advances in Linear Algebra & Matrix Theory 2019年第1期9卷 1-19页

作者： jean-francois Niglio Department of Mathematics Kingston University London UK

In this article, we wish to expand on some of the results obtained from the first article entitled Projection Theory. We have already established that one-parameter projection operators can be constructed from the unit circle . As discussed in the previous article these operators form a Lie group known as the Projection Group. In the first section, we will show that the concepts from my first article are consistent with existing theory [1] [2]. In the second section, it will be demonstrated that not only such operators are mutually congruent but also we can define a group action on ?by using the rotation group [3] [4]. It will be proved that the group acts on elements of ?in a non-faithful but ∞-transitive way consistent with both group operations. Finally, in the last section we define the group operation ?in terms of matrix operations using the operator and the Hadamard Product;this construction is consistent with the group operation defined in the first article.

关键词： Projection Theory Projection Manifolds Projectors Congruent Projection Matrices

Differential Homological Algebra and General Relativity

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Journal of Modern Physics 2019年第12期10卷 1454-1486页

作者： jean-francois Pommaret CERMICS Ecole des Ponts Paris Tech Paris France

In 1916, F.S. Macaulay developed specific localization techniques for dealing with “unmixed polynomial ideals” in commutative algebra, transforming them into what he called “inverse systems” of partial differential equations. In 1970, D.C. Spencer and coworkers studied the formal theory of such systems, using methods of homological algebra that were giving rise to “differential homological algebra”, replacing unmixed polynomial ideals by “pure differential modules”. The use of “differential extension modules” and “differential double duality” is essential for such a purpose. In particular, 0-pure differential modules are torsion-free and admit an “absolute parametrization” by means of arbitrary potential like functions. In 2012, we have been able to extend this result to arbitrary pure differential modules, introducing a “relative parametrization” where the potentials should satisfy compatible “differential constraints”. We recently noticed that General Relativity is just a way to parametrize the Cauchy stress equations by means of the formal adjoint of the Ricci operator in order to obtain a “minimum parametrization” by adding sufficiently many compatible differential constraints, exactly like the Lorenz condition in electromagnetism. In order to make this difficult paper rather self-contained, these unusual purely mathematical results are illustrated by many explicit examples, two of them dealing with contact transformations, and even strengthening the comments we recently provided on the mathematical foundations of General Relativity and Gauge Theory. They also bring additional doubts on the origin and existence of gravitational waves.

关键词： Homological Algebra Extension Module Torsion-Free Module Pure Module Purity Filtration Involution Electromagnetism General Relativity

Peace, Peace to the Far and the Near： Who Comes First？

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Journal of Philosophy Study 2017年第5期7卷 261-268页

作者： jean-francois REY

The Projective Group as a Topological Manifold

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Advances in Linear Algebra & Matrix Theory 2018年第4期8卷 134-142页

作者： jean-francois Niglio Department of Mathematics Kingston University London UK

In this article, we start by a review of the circle group? [1] and its topology induced [1] by the quotient metric, which we later use to define a topological structure on the unit circle . Using points on? under the complex exponential map, we can construct orthogonal projection operators. We will show that under this construction, we arrive at a topological group, denoted? of projection matrices. Together with the induced topology, it will be demonstrated that? is Hausdorff and Second Countable forming a topological manifold. Moreover, I will use an example of a group action on? to generate subgroups of?.

关键词： Projection Orthogonal Projections Projective Operators Projective Manifolds

The Mathematical Foundations of General Relativity Revisited

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Journal of Modern Physics 2013年第8期4卷 223-239页

作者： jean-francois Pommaret CERMICS Ecole des Ponts ParisTech Marne-la-Vall_ee Cedex 02 France

The purpose of this paper is to present for the first time an elementary summary of a few recent results obtained through the application of the formal theory of partial differential equations and Lie pseudogroups in order to revisit the mathematical foundations of general relativity. Other engineering examples (control theory, elasticity theory, electromagnetism) will also be considered in order to illustrate the three fundamental results that we shall provide successively. 1) VESSIOT VERSUS CARTAN: The quadratic terms appearing in the “Riemann tensor” according to the “Vessiot structure equations” must not be identified with the quadratic terms appearing in the well known “Cartan structure equations” for Lie groups. In particular, “curvature + torsion” (Cartan) must not be considered as a generalization of “curvature alone” (Vessiot). 2) JANET VERSUS SPENCER: The “Ricci tensor” only depends on the nonlinear transformations (called “elations” by Cartan in 1922) that describe the “difference” existing between the Weyl group (10 parameters of the Poincaré subgroup + 1 dilatation) and the conformal group of space-time (15 parameters). It can be defined without using the indices leading to the standard contraction or trace of the Riemann tensor. Meanwhile, we shall obtain the number of components of the Riemann and Weyl tensors without any combinatoric argument on the exchange of indices. Accordingly and contrary to the “Janet sequence”, the “Spencer sequence” for the conformal Killing system and its formal adjoint fully describe the Cosserat equations, Maxwell equations and Weyl equations but General Relativity is not coherent with this result. 3) ALGEBRA VERSUS GEOMETRY: Using the powerful methods of “Algebraic Analysis”, that is a mixture of homological agebra and differential geometry, we shall prove that, contrary to other equations of physics (Cauchy equations, Cosserat equations, Maxwell equations), the Einstein equations cannot be “parametrized”, that is the ge

关键词： General Relativity Riemann Tensor Weyl Tensor Ricci Tensor Einstein Equations Lie Groups Lie Pseudogroups Differential Sequence Spencer Operator Janet Sequence Spencer Sequence Differential Module Homological Algebra Extension Modules Split Exact Sequence