检索结果-南通市图书馆

Archaea and the human gut:New beginning of an old story

World Journal of Gastroenterology 2014年第43期20卷 16062-16078页

作者： Nadia Gaci Guillaume Borrel William Tottey paul William O’Toole jean-Fran?ois Brugère EA-4678 CIDAM Clermont UniversitéUniversité d’AuvergneF-63000 Clermont-FerrandFrance School of Microbiology and Alimentary Pharmabiotic Centre University College CorkCorkIreland

Methanogenic archaea are known as human gut inhabitants since more than 30 years ago through the detection of methane in the breath and isolation of two methanogenic species belonging to the order Methanobacteriales, Methanobrevibacter smithii and Methanosphaera stadtmanae. During the last decade, diversity of archaea encountered in the human gastrointestinal tract (GIT) has been extended by sequence identification and culturing of new strains. Here we provide an updated census of the archaeal diversity associated with the human GIT and their possible role in the gut physiology and health. We particularly focus on the still poorly characterized 7th order of methanogens, the Methanomassiliicoccales, associated to aged population. While also largely distributed in non-GIT environments, our actual knowledge on this novel order of methanogens has been mainly revealed through GIT inhabitants. They enlarge the number of final electron acceptors of the gut metabolites to mono- di- and trimethylamine. Trimethylamine is exclusively a microbiota-derived product of nutrients (lecithin, choline, TMAO, L-carnitine) from normal diet, from which seems originate two diseases, trimethylaminuria (or Fish-Odor Syndrome) and cardiovascular disease through the proatherogenic property of its oxidized liver-derived form. This therefore supports interest on these methanogenic species and its use as archaebiotics, a term coined from the notion of archaea-derived probiotics.

关键词： Human gut microbiota Methanogens Methanomassiliicoccus Methanomethylophilus Trimethylaminuria Trimethylamine Methane Cardiovascular disease Archaebiotics Probiotics

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Reducing loss of significance in the computation of Earth-based two-way Doppler observables for small body missions

引用

Research in Astronomy and Astrophysics 2021年第8期21卷 75-90页

作者： Wei-Tong Jin Fei Li Jian-Guo Yan Xuan Yang Mao Ye Wei-Feng Hao Thomas paul Andert jean-Pierre Barriot State Key Laboratory of Information Engineering in Surveying Mapping and Remote SensingWuhan UniversityWuhan 430079China State Key Laboratory of Satellite Navigation System and Equipment Technology Shijiazhuang 050200China Chinese Antarctic Center of Surveying and Mapping Wuhan UniversityWuhan 430079China Universitat der Bundeswehr München NeubibergBayern85579Germany University of French Polynesia BP 6570F-98702 Faa'aTahitiFrench Polynesia

Two-way Doppler measurement is a typical Earth-based radiometric technique for interplanetary spacecraft navigation and gravity science *** most widely used model for the computation of two-way Doppler observables is Moyer’s differenced-range Doppler(DRD) formula,which is based on a Schwarzschild approximation of the Solar-System ***,the computation of range difference in DRD formula is sensitive to round-off errors due to approximate numbers defined by the norm IEEE754 in all *** paper presented two updated models and their corresponding detailed instructions for the computation of the two-way Doppler observables so as to impair the effects of this type of numerical *** two models were validated by two case studies related to the Rosetta mission—asteroid Lutetia flyby and comet 67 P/Churyumov-Gerasimenko orbiting *** these two cases,the numerical noise from the updated models can be reduced by two orders-of-magnitude in the computed two-way Doppler *** results showed an accuracy from better than 6 × 10^(-3) mm s^(-1) at 1 s counting time interval to better than 3 × 10^(-5) mm s^(-1) at 60 s counting time interval.

关键词： methods:numerical space vehicles planets and satellites:general

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Phase coexistence properties of liquid mercury:a simulation study

引用

Rare Metals 2006年第5期25卷 567-571页

作者： jean-Louis Bretonnet jean-Marc Bomont Laboratoire de Physique des Milieux Denses Université Paul Verlaine1bd F.D.Arago57078 MetzCedex 3France

The thermophysical properties of expanded liquid mercury have been investigated along the liquid-vapor coexistence curve by using Monte Carlo and Molecular Dynamic simulations. For the purpose, an empirical state dependent interatomic potential for the region of dense metallic liquid is used, while the state dependence is not necessary near the cliffcal point. In order to test the validity of this potential, we determine the surface layering and the sound velocity, two properties very sensitive to the choice of the potential. Our results are in quite good agreement with other theoretical results and to the experimental data available in the literature.

关键词： mercury simulation phase coexistence liquid state

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Depositional age and tectonic environment of the Gouap banded iron formations from the Nyong group,SW Cameroon:Insights from isotopic,geochemical and geochronological studies of drillcore samples

引用

Geoscience Frontiers 2021年第2期12卷 549-572页

作者： Landry Soh Tamehe Chongtao Wei Sylvestre Ganno Carlos Alberto Rosiere jean paul Nzenti Chesther Gatse Ebotehouna Guanwen Lu Key Laboratory of CBM Resources and Reservoir Formation Process Chinese Ministry of EducationChina University of Mining and TechnologyXuzhouJiangsu221116China Department of Earth Sciences University of Yaounde IP.O.Box 812YaoundeCameroon Department of Geology Universidade Federal de Minas Gerais31270-901Belo HorizonteMinas GeraisBrazil School of Civil and Environmental Engineering University of Science and Technology BeijingBeijing 100083China

The discovery of the Gouap banded iron formations(BIFs)-hosted iron mineralization in the northwestern of the Nyong Group(Ntem Complex)in southwestern Cameroon provides unique insights into the geology of this *** this contribution,we firstly report detailed study of geochemistry,isotopic and geochronology of well preserved samples of the Gouap BIFs collected from diamond *** Gouap BIFs consist mainly of amphibole BIFs and amphibole-pyrite BIFs characterized by dominant Fe_(2)O_(3)+SiO_(2)contents and variable contents of CaO,MgO and SO_(3),consistent with the presence of amphibole,chlorite,epidote and pyrite,formed during amphibolite facies metamorphism and overprinted hydrothermal *** amphibole–pyrite BIFs are typically enriched in trace and rare earth elements(REE)compared to the amphibole BIFs,suggesting the influence of detrital materials as well as secondary hydrothermal *** Post Archean Australian Shale(PAAS)-normalized REE–Y profiles of the Gouap BIFs display positive La,Eu anomalies,weak negative Ce anomalies,indicating a mixture of low-temperature hydrothermal fluids and relatively oxic conditions probably under relative shallow *** present here the first isotopic data of BIFs within the Ntem ***δ^(30)Si_(NBS28)values of the quartz from the Gouap BIFs vary from-1.5‰to-0.3‰and from-0.8‰to-0.9‰for the amphibole BIFs and amphibole–pyrite BIFs,*** quartz hasδ^(18)OV-SMOW values of 6.8‰–9.5‰(amphibole BIFs)and 9.2‰–10.6‰(amphibole–pyrite BIFs).The magnetite from the Gouap BIFs showsδ^(18)O values ranging from-3.5‰to-1.8‰and from-3‰to-1.7‰for the amphibole BIFs and amphibole–pyrite BIFs,***,the pyrite grains in the amphibole–pyrite BIFs displayδ34S values of 1.1‰–1.8‰.All isotopic data of the Gouap BIFs confirm that they might have precipitated from low-temperature hydrothermal fluids with detrital input distant from the volcanic *** to their geochemical and isotop

关键词： Gouap Banded iron formations Isotope geochemistry Zircon geochronology Ryacian period Brasiliano-Congo orogeny

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Balance control during gait initiation: State-of-the-art and research perspectives

引用

World Journal of Orthopedics 2017年第11期8卷 815-828页

作者： Eric Yiou Teddy Caderby Arnaud Delafontaine paul Fourcade jean-Louis Honeine Laboratoire CIAMS Université Paris-Sud Université Paris-Saclay Laboratoire CIAMS Université d’Orléans Laboratoire IRISSE UFR des Sciences de l’Homme et de l’Environnement Université de la Réunion Ecole Nationale de Kinésithérapie et Rééducation Department of Public Health Experimental and Forensic Medicine University of Pavia

It is well known that balance control is affected by aging, neurological and orthopedic conditions. Poor balance control during gait and postural maintenance are associated with disability, falls and increased mortality. Gait initiation-the transient period between the quiet standing posture and steady state walking-is a functional task that is classically used in the literature to investigate how the central nervous system(CNS) controls balance during a whole-body movement involving change in the base of support dimensions and center of mass progression. Understanding how the CNS in able-bodied subjects exerts this control during such a challenging task is a prerequisite to identifying motor disorders in populations with specific impairments of the postural system. It may also provide clinicians with objective measures to assess the efficiency of rehabilitation programs and better target interventions according to individual impairments. The present review thus proposes a state-of-the-art analysis on:(1) the balance control mechanisms in play during gait initiation in able bodied subjects and in the case of some frail populations; and(2) the biomechanical parameters used in the literature to quantify dynamic stability during gait initiation. Balance control mechanisms reviewed in this article included anticipatory postural adjustments, stance leg stiffness, foot placement, lateral ankle strategy, swing foot strike pattern and vertical center of mass braking. Based on this review, the following viewpoints were put forward:(1) dynamic stability during gait initiation may share a principle of homeostatic regulation similar to most physiological variables, where separate mechanisms need to be coordinated to ensure stabilization of vital variables, and consequently; and(2) rehabilitation interventions which focus on separate or isolated components of posture, balance, or gait may limit the effectiveness of current clinical practices.

关键词： Balance control Anticipatory postural adjustments Leg stiffness Foot placement Lateral ankle strategy Foot strike pattern Vertical center of mass braking Dynamic stability Gait initiation Biomechanics

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Quantum Meteorites: An Extemporaneous Description of the System of the World

引用

Journal of Modern Physics 2015年第7期6卷 878-889页

作者： jean-paul Auffray Courant Institute of Mathematical Sciences New York University New York NY USA

We extemporaneously summarize the theoretical scheme we have introduced recently in this note to account for the (hidden) functioning of the System of the World at the quantum level. We further explore the relevance, the pertinence and the potential validity of this scheme. We obtain new fundamental results, bearing notably on the nature and the origin of the “virtual particles” conventionally called upon in quantum field theories to explain the Casimir Effect. We define the concept of quantum meteorites in this context. We disable the Heisenberg Uncertainty Principle, judged to be a (mis) interpretation of otherwise legitimate observations, and we replace it with our new XQP Absolute Certainty Principle.

关键词： Xonic Quantum Physics Casimir Effect Virtual Photons Uncertainty Principle Planck Length Quantum Meteorites

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

The Production of the Sequence -UI- by Francophone Learners of English

引用

Sino-US English Teaching 2017年第4期14卷 262-271页

作者： jean-paul Kouega University of Yaounde I Yaounde Cameroon

This paper considers the renderings of the sequence -UI- by Cameroonian, Gabonese, and native French users learning English with the view to finding out whether French users speaking different L 1s pronounce this sequence in different or similar ways. The data were recordings of items containing -UI- and the contrastive method of analysis was used. It was found that this sequence is rendered in two ways by the learners. Besides, different L2 French-speaking learners tend to pronounce it in the same ways and so do L2 and L1 French-speaking learners. It can therefore be hypothesised that Francophone speakers tend to draw more from French when they speak English than from their respective L 1s.

关键词： L3 English learner France Cameroon Gabon consonant vowel

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

E-Infinity Dualities, Discontinuous Spacetimes, Xonic Quantum Physics and the Decisive Experiment

引用

Journal of Modern Physics 2014年第15期5卷 1427-1436页

作者： jean-paul Auffray Courant Institute of Mathematical Sciences New York University New York USA

Using powerful concepts and tools borrowed from the seminal arsenal connecting physics fundamentals with esoteric set theoretical operations developed in recent years by Alexandria E-infinity theoretician M. S. El Naschie, this paper explores the deep implications of some of the dualities Dr El Naschie has identified and analyzed in his exposes, connecting them with our own Xonic Quantum Physics (XQP) which places dynamical action rather than spacetime and energy at the core of the System of the World.

关键词： E-Infinity El Naschie Space Time Spacetime Topology Cantor Sets Energy Xon Xonic Quantum Physics Planck Scale Dirac Electron

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

<i>E</i>Infinity, the Zero Set, Absolute Space and the Photon Spin

引用

Journal of Modern Physics 2015年第5期6卷 536-545页

作者： jean-paul Auffray ex: Courant Institute of Mathematical Sciences New York University New York USA ex: American Institute of Physics New York USA

As defined and used in General Relativity calculations, spacetime is a strictly classical construct which does not incorporate in any way, shape or form the concept of quantum. While reviewing the efforts that Alexandria theoretician M. S. El Naschie has made to resolve the dichotomy, we discovered that his E infinity theory contains a Cantor set which has characteristics specified by Isaac Newton for Absolute space. We show that this unexpected connection leads to an understanding of the mysterious origin of the one and only attribute that all particles listed in the Standard Model of Elementary Particles possess—including notably the photon—and which has remained unexplained hitherto: spin. This most rewarding result reinforces our belief in the relevance of the E infinity basic concepts in relation to our own Xonic Quantum Physics (XQP) which places dynamical action rather spacetime and energy at the core of the System of the World.

关键词： Quantum Foam E Infinity Xonic Quantum Physics Newton Absolute Space Photon Spin

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

On an Intriguing Invention Albert Einstein Made Which Has Gone Unnoticed Hitherto

引用

Journal of Modern Physics 2015年第11期6卷 1478-1491页

作者： jean-paul Auffray ex: Courant Institute of Mathematical Sciences New York University New York USA

We retrieve three mysterious sentences Albert Einstein wrote in the early years of his wondrous scientific career. We examine their implications and we suggest that they provide a surprising new basis for Quantum Phys... 详细信息

关键词： Einstein Absolute Measurements Electromagnetic Energy m = E/c2 Space Points Dark Energy M. S. El Naschie Quantum Meteorites

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：