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Dietary methionine sources and levels modulate the intestinal health status of broiler chickens

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Animal Nutrition 2023年第4期15卷 242-255页

作者： Lu Gong Tahir Mahmood Yves mercier Huiping Xu Xiaodan Zhang Yizhu Zhao Yimeng Luo Yuming Guo State Key Laboratory of Animal Nutrition College of Animal Science and TechnologyChina Agricultural UniversityBeijing100193China Adisseo France S.A.S 03600CommentryFrance

Given the key role of methionine in biological processes,adequate methionine should be provided to meet the nutritional ***-2-hydroxy-4-(methylthio)-butanoic acid(DL-HMTBA)has been considered as an important source of ***,the effects of different sources and levels of methionine on the intestinal health status have not been clarified *** experiment was carried out to investigate the effects of different dietary sources and levels of methionine on the intestinal epithelial barrier,inflammatory cytokines expression,ileal morphology,microbiota composition,and cecal short chain fatty acids(SCFA)*** this purpose,720 male Arbor Acre broiler chicks at 1 d old were randomly assigned to a 2×3 factorial arrangement with 2 methionine sources(DL-methionine and DLHMTBA)and 3 total sulfur amino acids(TSAA)levels(80%,100%,and 120%of Arbor Acre recommendation).The results showed that DL-HMTBA supplementation promoted intestinal physical barrier at both gene expression level of claudin-1 and serum diamine oxidase level(P<0.05),and the inflammatory cytokine IL-6 m RNA expression was down-regulated by dietary DL-HMTBA supplementation compared with the DL-methionine group(P<0.05).Meanwhile,an upregulated gene expression of claudin-1 and zonula occluden-1(ZO-1)were observed in the low-TSAA treatment on d 14(P<0.05),whereas this treatment increased the expression of IL-1βand IL-6(P<0.05).Villus height to crypt depth ratio was high(P<0.05)in the middle-level TSAA ***,DL-HMTBA supplementation optimized the microbiota of the ileum especially the relative abundance of Lactobacillus,where the digestion and absorption were completed,and elevated the concentrations of SCFA(acetate,propionate,and butyrate)in the cecal content on d 21(P<0.01).In conclusion,dietary DL-HMTBA supplementation improved the intestinal barrier function,immune homeostasis and optimized the microbiota to promote intestinal health status in broiler chickens.

关键词： Chicken Methionine 2-Hydroxy-4-(methylthio)-butanoic acid Intestinal health Intestinal barrier

Several Ways to Calculate the Universal Gravitational Constant <i>G</i>Theoretically and Cubic Splines to Verify Its Measured Value

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Journal of Modern Physics 2020年第9期11卷 1428-1465页

作者： Claude mercier Independent Researcher Baie-Comeau Canada

In 1686, Newton discovered the laws of gravitation [1] and predicted the universal gravitational constant . In 1798, with a torsion balance, Cavendish [2] measured . Due to the low intensity of gravitation, it is difficult to obtain reliable results because they are disturbed by surrounding masses and environmental phenomena. Modern physics is unable to link G with other constants. However, in a 2019 article [3], with a new cosmological model, we showed that G seams related to other constants, and we obtained a theoretical value of . Here, we want to show that our theoretical value of G is the right one by interpreting measurements of G with the help of a new technique using cubic splines. We make the hypothesis that most G measurements are affected by an unknown systematic error which creates two main groups of data. We obtain a measured value of . Knowing that our theoretical value of G is in agreement with the measured value, we want to establish a direct link between G and as many other constants as possible to show, with 33 equations, that G is probably linked with most constants in the universe. These equations may be useful for astrophysicists who work in this domain. Since we have been able to link G with Hubble parameter H0 (which evolve since its reverse gives the apparent age of the universe), we deduce that G is likely not truly constant. It’s value probably slowl

关键词： Universal Gravitational Constant G Newton Cavendish Einstein Cubic Splines

Kinematic History and Changes in the Tectonic Stress Regime during the Cenozoic along the Qinling and Southern Tanlu Fault Zones

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Acta Geologica Sinica(English Edition) 1999年第3期73卷 264-274页

作者： ZHANG Yueqiao Pierre Vergèly Jacques-Louis mercier WANG Yongmin ZHANG Yong HUANG Dezhi Institute of Geomechanics Chinese Academy of GeologyBeijing 100081China URA-CNRS:Géophysique et Géodynamique Interne Universitéde Parie-SudBatment 509F-91405Orsay-CedexFrance Institute of Geology Bureau of Geology and Mineral Resouces of Anhui ProvinceHefeiChina

Since the mid-late Eocene, North China has been subjected to extensional stress, resulting in the formation and development of basins. The dynamic origin of this crustal extension has long been an issue of debate. This paper presents the results of kinematic analyses of faults obtained from two seperated areas in North China. In the Weihe graben situated on the southernmost margin of the Ordos block, analyses of fault kinematics were coupled with an analysis of the basin's subsidence history. Three successive extensional tectonic phases accompaning the basin's formation and development have been distinguished. The Palaeogene extension was oriented in a WNW-ESE direction; the Neogene extension in a NE-SW direction and the Pliocene-Quaternary extension in a NW-SE direction. Such changes have also been recorded by fault kinematics along the southern Tanlu fault zone. This has been demonstrated by three successive sets of fault striations indicating normal dip slip resulting from NW-SE extension, then left-lateral slip with a normal component resulting from NE-SW extension, and right-lateral slip with a minor normal component, respectively. The kinematic history of faults and their chronological evolution indicate changes in continental dynamics acting in North China over Cenozoic time.

关键词： fault kinematics tectonic stress regime Qinling and Tanlu fault zones

Absorption of methionine sources in animals-is there more to know?

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Animal Nutrition 2023年第1期12卷 159-170页

作者： Philippe Becquet Mercedes Vazquez-Anon Yves mercier Dolores I.Batonon-Alavo Frances Yan Karen Wedekind Tahir Mahmood IMAA BrusselsBelgium Novus International Saint CharlesMissouriUSA Adisseo France SAS AntonyFrance

This literature review evaluates the absorption of methionine (Met) sources such as 2-hydroxy-4-methylthiobutyric acid (HMTBa), its calcium salts (HMTBa-Ca), and DL-methionine (DL-Met) by focusing on the state of knowledge regarding the absorption mechanism, experimental methodology, and factors affecting their absorption. The 2 Met sources differ in mechanism and site of absorption due to differences in their chemical characteristics and enzymatic conversion. This review addresses diffusion- and transport-mediated absorption systems for amino acids and carboxylic compounds, best elucidated by in vitro, ex vivo, and in vivo experimental models. Opportunities and limitations in the use of radioisotopes to depict absorption sites as well as host and microbial metabolism are described. Physiological and environmental conditions that lead to changes in gut absorptive capacity and the impact of Met source absorption are also evaluated. This review concludes that any comparison between HMTBa and DL-Met should consider their different behaviors during the absorption phase. Hence, the chemical characteristics of these 2 molecules entail different absorption sites and mechanisms, from passive absorption in the case of HMTBa and HMTBa-Ca to active transporters for DL-Met, HMTBa, and HMTBa-Ca. In addition, the different conversion modes of these 2 molecules further differentiate their absorption modes. Considering these important differences, it is easier to understand the apparent divergence between the conclusions of existing publications. When comparing these 2 molecules, it is recommended to properly adapt to the conditions under which the absorption of Met sources is evaluated.

关键词： DL-Methionine Hydroxy-analog of methionine 2-Hydroxy-4-methylthiobutyric acid AbsorptionM ethodology

Calculation of the Universal Gravitational Constant, of the Hubble Constant, and of the Average CMB Temperature

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Journal of Modern Physics 2019年第6期10卷 641-662页

作者： Claude mercier Independent Researcher Baie-Comeau Canada

Dirac made the hypothesis that all large, dimensionless numbers that could be constructed from the important natural units of cosmology and atomic theory were connected [1] [2]. Although Dirac did not succeed in exactly matching all these numbers, he suspected that there was a way to unify all of them. Dirac’s hypothesis leads to the N constant which unifies most of physics’ parameters. It represents the maximum number of photons with a wavelength equal to the universe circumference. Using a new cosmological model, we found the β constant which represents the ratio between the expansion speed of matter in the universe and the speed of light. With these constants, we can now calculate accurately several physics parameters, including the universal gravitational constant G, the Hubble constant H0, and the average temperature T of the cosmological microwave background (CMB). Our equations show that G, H0 and T are not really constant over space and time.

关键词： Gravitational Constant Hubble Dirac Large Numbers Hypothesis CMB/CMBR

Calculation of the Mass of the Universe, the Radius of the Universe, the Age of the Universe and the Quantum of Speed

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Journal of Modern Physics 2019年第8期10卷 980-1001页

作者： Claude mercier Independent Researcher Baie-Comeau Canada

The universe is vast and when we look at the sky, its parameters (dimensions, mass, and age) seems limitless. Lemaître proposed that the universe began from a primeval-atom [1] which was later ironically nicknamed by Hoyle “Big Bang” in a BBC broadcast in 1949 [2]. From general relativity, Einstein proposed a cosmological model [3] with a spatially finite universe. He assumed a uniform distribution of matter in a huge 4-D sphere. Even if his equations were showing that the universe was either contracting or expanding, Einstein introduced the “cosmological constant” in his equation to force the universe to be static (being consistent with the general way of thinking of his time). In 1929, from observations of galaxies, Hubble found that the universe was expanding. From that moment, Einstein discarded his cosmological constant as an unnecessary fudge factor. Many cosmological models have been built over time. Each of them excels in explaining some aspects of the universe. We consider that the global topology of the universe is not known, but making the assumptions that it is relatively homogenous and isotropic, its extrapolated local topology leads us to some global “apparent” parameters. From our new cosmological model, we calculate the main parameters of the universe which are its apparent mass mu, its apparent curving radius Ru, its apparent age Tu and the “quantum of speed” εv. The quantum of speed is a new notion in physics. It is the smallest speed increment that may exist. For metrology purposes, we calculate these parameters from the most precise physics’ parameters available.

关键词： Mass of the Universe Hubble Radius Age of the Universe Quantum of Speed Dirac Large Numbers Hypothesis

A systematic review of metabolism of methionine sources in animals:One parameter does not convey a comprehensive story

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Animal Nutrition 2023年第2期13卷 31-49页

作者： Philippe Becquet Mercedes Vazquez-Anon Yves mercier Karen Wedekind Tahir Mahmood Dolores I.Batonon-Alavo Frances Yan International Methionine Analogue Association Regus Brussels City CentreStephanie SquareAvenue Louise65B-1050 BrusselsBelgium Novus International Inc. 20 Research Park DriveSaint CharlesMissouri 63304USA Adisseo France SAS Antony Parc II10 Place Du General de GaulleAntony 92160France

The goal of this review article,based on a systematic literature search,is to critically assess the state of knowledge and experimental methodologies used to delineate the conversion and metabolism of the 2 methionine(Met)sources DL-methionine(DL-Met)and DL-2-hydroxy-4-(methylthio)butanoic acid(HMTBa).The difference in the chemical structures of HMTBa and DL-Met indicates that these molecules are absorbed and metabolized differently in *** review explores the methodologies used to describe the 2-step enzymatic conversion of the 3 enantiomers(D-HMTBa,L-HMTBa and D-Met)to L-Met,as well as the site of conversion at the organ and tissue *** work was published documenting the conversion of HMTBa and D-Met into L-Met and,consequently,the incorporation into protein using a variety of in vitro techniques,such as tissue homogenates,cell lines,primary cell lines,and everted gut sacs of individual *** studies illustrated the role of the liver,kidney,and intestine in the con-version of Met precursors into L-Met.A combination of in vivo studies using stable isotopes and infusions provided evidence of the wide conversion of HMTBa to L-Met by all tissues and how some tissues are net users of HMTBa,whereas others are net secreters of L-Met derived from *** of D-Met to L-Met in organs other than the liver and kidney is poorly *** methodology cited in the literature to determine conversion efficiency ranged from measurements of urinary,fecal,and respiratory excretion to plasma concentration and tissue incorporation of isotopes after intraperitoneal and oral *** observed between these methodologies reflect differences in the metabolism of Met sources rather than differences in conversion *** factors affecting conversion efficiency are explored in this paper and are mostly associated with extreme dietary conditions,such as noncommercial crystalline diets that are very deficient in total sulfur amino a

关键词： DL-Methionine Hydroxy-analog of methionine 2-Hydroxy-4-(methylthio)butanoic acid Conversion Metabolism Methodology

Advanced protection against environmental degradation of silver mirror stacks for space application

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Journal of Materials Science & Technology 2021年第5期64卷 1-9页

作者： Rajendra Kurapati Vincent Maurice Antoine Seyeux Lorena H.Klein Dimitri mercier Gregory Chauveau Catherine Grees-Besset Loic Berthod Philippe Marcus PSL Research University CNRS-Chimie ParisTechInstitut De Recherche De Chimie ParisPhysical Chemistry of Surfaces Group11 Rue Pierre Et Marie Curie75005 ParisFrance CILAS MARSEILLE 600 Avenue De La Roche FourcadePole ALPHA Sud-Saint Mitre13400 AubagneFrance CNES Sous-direction Assurance QualitéService TechnologiesMatériaux Et Procédés18 AvenueÉdouard Belin31401 ToulouseFrance

Protection of silver mirror stacks from environmental degradation before launching is crucial for space ***,we report a comparative study of the advanced protection of silver mirror stacks for space telescopes provided by SiO_(2)and Al_(2)O_(3)coatings in conditions of accelerated aging by *** model silver stack samples were deposited by cathodic magnetron sputtering on a reference silica substrate for optical applications and a surface-pretreated SiC *** aging was per-formed in dry and more severe wet *** micrographic observations,surface and interface analysis by Time-of Flight Secondary Ion Mass Spectrometry(ToF-SIMS)and reflectivity measurements were combined to comparatively study the effects of *** results show a lower kinetics of degradation by accelerated aging of the stacks protected by the alumina coating in comparable test conditions.

关键词： Mirror layers Protection Layers Silver Atmospheric corrosion Accelerated aging Surface analysis Space applications

Role of acetic acid on U(Ⅵ) sorption on silica

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Nuclear Science and Techniques 2015年第1期26卷 127-134页

作者：赵羽佳韦悦周 Florence mercier-Bion Gregory Lefevre School of Nuclear Science and Engineering Shanghai Jiao Tong University Institut de Physique Nucleaire d’Orsay CNRS/IN2P3 Universite Paris-Sud 1115 rue Georges Clemenceau Orsay Cedex 91406 France Institut de Recherche de Chimie Paris CNRS-Chimie ParisTech 11 rue Pierre et Marie Curie Paris 75005 France

The influence of acetate on U(Ⅵ) sorption on silica from aqueous solutions was studied at p H 2–7 by complementary experimental methods of macroscopic measurement, spectroscopic investigation and thermodynamic calculation. Sorption percentage of U(Ⅵ) in the absence and in the presence of different acetate concentrations was determined by batch sorption procedures. Attenuated total reflection Fourier transform infra-red spectroscopy(ATR-FTIR) was used to elucidate the mechanisms of uranyl sorption on silica in the presence of acetate, by investigating, in-situ, the changes in the U(Ⅵ) sorption on silica surface in presence of ligand: the absorption bands of carboxylate ν(COO) in the range 1300–1700 cm-1and those around 850–950 cm-1of uranyl species νas(UO2) are followed. The decrease of U(Ⅵ) sorption with increasing acetate concentration was observed. Sorption of U(Ⅵ)-acetate(U-Ac) species on silica surface was demonstrated for the first ***-FTIR investigations clearly evidenced the absorption bands characteristic of sorbed U-Ac complexes both from the acetate and uranyl spectral regions those the wavenumbers correspond to sorbed species. No sequence effect of acetate and uranyl on the sorption on silica in ternary systems U(Ⅵ)-acetate-silica was observed from the sorption data. From the ATR-FTIR investigations, we can induce that the sorption of U-Ac leads to chemical equilibria and makes possible the modeling of sorption isotherms by surface complexation models. The related thermodynamic constants were modeled using CCM surface complexation modeling.

关键词：吸附作用傅里叶变换红外光谱硅胶 VI 醋酸 ATR-FTIR 表面络合模型 U(Ⅵ)