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Anthropogenic Threats to Degraded Forest Land in the Savannahs’ Region of Togo from 1984 to 2020, West Africa

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Journal of Geoscience and Environment Protection 2024年第1期12卷 164-179页

作者： Kossi Senyo Ehlui Wouyo Atakpama henrik von Wehrden Alagie bah Edinam Kola Christian Anthony-Krueger Hodabalo Egbelou Kokouvi bruno Kokou Tchaa boukpessi West Africa Science Service Center on Climate Change and Adapted Land Use (WASCAL) University of the Gambia Banjul Gambia Laboratoire de Recherche sur la Dynamique des Milieux et des Sociétés Université de Lomé Lomé Togo Laboratoire de botanique et écologie Végétale Département Botanique Faculté des Sciences Université de Lomé Lomé Togo West Africa Plant Red List Authority (WAPRLA) IUCN Species Survival Commission Gland Switzerland Faculty of Sustainability Center of Methods Leuphana University of Lüneburg Lüneburg Germany Center for International Forestry Research and World Agroforestry (CIFOR-ICRAF) Nairobi Kenya Laboratoire de Recherche sur la Dynamique des Milieux et des Sociétés (LARDYMES) Department of Geography FSHS University of Lomé Lome Togo Department of Science Education University of Cape Coast Cape Coast Ghana Institut Togolais de Recherches Agronomiques (ITRA) Lomé Togo Laboratoire de Recherches biogéographiques et d’Etudes Environnementales Department of Geography University of Lome Lome Togo

This study focuses on the landscape dynamics of the savannahs’ region in the far north of Togo. based on a literature review and satellite images analysis using GIS and remote sensing, the study aims to ascertain the effects of anthropogenic threats on the forest coverage of the Savannahs’ Region between 1984 to 2020. The objective is to clarify the dynamics of land use in the region from 1984 to 2000 and from 2000 to 2020. The findings indicate a significant decline in forest coverage within the region from 1984 to 2020, a trend attributed to land use patterns. Dry forests in the Savannah region are largely converted to farmlands, housing, dry savannahs or agroforestry parks, leading to a steady reduction in forest areas.

关键词： Forest Degradation Land Use Land Cover Savannahs Region Togo

The tensor embedding for a Grothendieck cosmos

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Science China Mathematics 2023年第11期66卷 2471-2494页

作者： henrik Holm Sinem Odabasi Department of Mathematical Sciences University of CopenhagenCopenhagen 02100Denmark Instituto de Ciencias Físicas y Matemáticas Universidad Austral de ChileValdivia 5090000Chile

While the Yoneda embedding and its generalizations have been studied extensively in the literature,the so-called tensor embedding has only received a little *** this paper,we study the tensor embedding for closed symmetric monoidal categories and show how it is connected to the notion of geometrically purity,which has recently been investigated in the works of Enochs et al.(2016)and Estrada et al.(2017).More precisely,for a Grothendieck cosmos,i.e.,a bicomplete Grothendieck category V with a closed symmetric monoidal structure,we prove that the geometrically pure exact category(V,ε■)has enough relative injectives;in fact,every object has a geometrically pure injective *** also show that for some regular cardinalλ,the tensor embedding yields an exact equivalence between(V,ε■)and the category ofλ-cocontinuous V-functors from Presλ(V)to V,where the former is the full V-subcategory ofλ-presentable objects in *** many cases of interest,λcan be chosen to be■0 and the tensor embedding identifies the geometrically pure injective objects in V with the(categorically)injective objects in the abelian category of V-functors from fp(V)to *** we explain,the developed theory applies,e.g.,to the category Ch(R)of chain complexes of modules over a commutative ring R and to the category Qcoh(X)of quasi-coherent sheaves over a(suitably nice)scheme X.

关键词： enriched functor exact category (pre)envelope (pure)injective object purity symmetric monoidal category tensor embedding Yoneda embedding

Fundamental influences of particles on stirred and unstirred venting processes of foaming systems

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Frontiers of Chemical Science and Engineering 2014年第2期8卷 141-148页

作者： henrik LEIMEISTER Jorg STEINbACH Department of Process Engineering Technische Universitat Berlin Strage des 17. Juni 135 10623 Berlin Germany

Venting is the common safety measure to protect plant equipment against excessive overpressure. So far, scenarios in which particles were part of the system and should have been accounted for did ignore their presence; the scenarios were treated like a two-phase system. Current research shows that particles can have a major influence on the venting behaviour. Experimental results indicate that particles affect level swell and relief flow especially of foamy systems. based on those results four different layers of influence of the particle have been identified and are presented in a first model. based on this model recommendations for the development of new and more complex models are given.

关键词： venting multi-phase

Harmonic Analysis for Real Spherical Spaces

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Acta Mathematica Sinica,English Series 2018年第3期34卷 341-370页

作者： bernhard KROTZ henrik SCHLICHTKRULL Universitat Paderborn Institut fiir MathematikWarburger Strafle 10033098 PaderbornGermany University of Copenhagen Department of MathematicsUniversitetsparken 5DK-2100 Copenhagen ODenmark

We give an introduction to basic harmonic analysis and representation theory for homogeneous spaces Z = G/H attached to a real reductive Lie group G. A special emphasis is made to the case where Z is real spherical.

关键词： Real spherical spaces harmonic analysis homogeneous spaces representation theory

A Spectral Coupled-Mode Formulation for Sound Propagation around Axisymmetric Seamounts

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Chinese Physics Letters 2010年第9期27卷 131-134页

作者：骆文于 SCHMIDT henrik State Key Laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences Beijing 100190 Department of Mechanical Engineering Massachusetts Institute of Technology Massachusetts 02139 U.S.A.

A spectral coupled-mode solution of the three-dimensional （319） acoustic field generated by a point source in the presence o[ an axisymmetric seamount is developed. based on the same theoretical foundation as the for- mulation presented by Taroudakis [3. Comput. Acoust. 4 （1996） 101], the present approach combines a spectral decomposition in azimuth with a coupled-mode theory for two-way range-dependent propagation. However, the earlier formulations are severely limited in terms of frequency, size and geometry o[ the seamount, the seabed composition, and the distance between the source and the seamount, and are there/ore severely limited in regard to realistic seamount problems. Without changing the fundamental theoretical foundation, the present approach applies a number of modifications to the formulation, leading to orders of magnitude improvement in numerical efficiency for realistic problems. Therefore, realistic propagation and scattering scenarios can be modeled, including effects of seamount roughness and realistic sedimentary structure.

关键词： Formulations

Three-Dimensional Mode Coupling around a Conical Seamount and the Use of Random Discretization

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Chinese Physics Letters 2010年第11期27卷 137-140页

Three-dimensional mode coupling around a conical seamount in an ocean waveguide is studied. It is shown that strong mode coupling occurs at the edge of a conical seamount for the incident normal modes with significant amplitudes below the top of the seamount. Therefore, mode coupling is critical for the investigation of the acoustic field around a seamount. In addition, we suggest the use of random discretization for representing smoothly varying bathymetry. For the use of uniform discretization, when the horizontal step size is greater than half of the wavelength, artificial diffraction lobes appear due to coherent backscatter. However, by using the random discretization scheme instead, such artificial diffraction lobes are diffused, resulting in a faster convergence rate.

关键词： Environmental and Earth science

Arabidopsis Mutants and the Network of M icrotu bu le-Associated Functions

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Molecular Plant 2008年第6期1卷 888-898页

作者： henrik buschmann Clive W. Lloyd Department of Cell and Developmental biology John Innes Centre 1 Colney Lane Norwich NR4 7UH UK

In early eukaryotes, the microtubule system was engaged in mitosis, intracellular transport, and flagellumbased motility. In the plant lineage, the evolution of a multicellular body involved the conservation of some core functions, the loss of others, and the elaboration of new microtubule functions associated with the multicellular plant habit. This diversification is reflected by the presence of both conserved （animal/fungi-like） and novel （plant-like） sequences encoding microtubule-related functions in the Arabidopsis genome. The collection of microtubule mutants has grown rapidly over recent years. These mutants present a wide range of phenotypes, consistent with the hypothesis of a functional diversification of the microtubule system. In this review, we focus on mutant analysis and, in particular, discuss double mutant analysis as a valuable tool for pinpointing pathways of gene function. A future challenge will be to define the complete network of genetic and physical interactions of microtubule function in plants. In addition to reviewing recent progress in the functional analysis of the ＇MAPome＇, we present an online database of Arabidopsis mutants impaired in microtubule functions.

关键词： cell division cell morphogenesis cytoskeleton genetics development Arabidopsis.

Geometric Counting on Wavefront Real Spherical Spaces

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Acta Mathematica Sinica,English Series 2018年第3期34卷 488-531页

作者： bernhard KROTZ Eitan SAYAG henrik SCHLICHTKRULL Universitat Paderborn Institut Jur MathematikWarburger Strafle 10033098 PaderbornDeutschland Department of Mathematics Ben Gurion University of the NegevP.O.B.653Be'er Sheva 84105Israel Department of Mathematics University of CopenhagenUniversitetsparken 5DK-2100 Copenhagen ODenmark

We provide L^p-versus L~∞-bounds for eigenfunctions on a real spherical space Z of wavefront type. It is shown that these bounds imply a non-trivial error term estimate for lattice counting on Z. The paper also serve... 详细信息

关键词： Homogeneous spaces real spherical spaces lattice counting error term wavefront lemma spectral analysis norm comparison of eigenfunctions

Polymorphisms in NF-κb,PXR,LXR,PPARγ and risk of inflammatory bowel disease

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World Journal of Gastroenterology 2011年第2期17卷 197-206页

作者： Vibeke Andersen Jane Christensen Anja Ernst bent A Jacobsen Anne Tjφnneland henrik b Krarup Ulla Vogel Department of Medical Viborg Regional Hospital Institute of Cancer Epidemiology Danish Cancer Society Department of Clinical biochemistry Aarhus University Hospital Department of Medical Gastroenterology Aarhus University Hospital National Food Institute Technical University of Denmark Institute for Science Systems and ModelsUniversity of Roskilde National Research Centre for the Working Environment

AIM:To investigate the contribution of polymorphisms in nuclear receptors to risk of inflammatory bowel disease(IbD) . METHODS:Genotypes of nuclear factor(NF) -κb(NFKb1) NFκb-94ins/del(rs28362491) ;peroxisome proliferatoractivated receptor(PPAR) -γ(PPARγ) PPARγPro12Ala(rs1801282) and C1431T(rs 3856806) ;pregnane X receptor(PXR) (NR1I2) PXR A-24381C(rs1523127) ,C8055T(2276707) ,and A7635G(rs 6785049) ;and liver X receptor(LXR) (NR1H2) LXR T-rs1405655-C and T-rs2695121-C were assessed in a Danish case-control study of 327 Crohn's disease patients,495 ulcerative colitis(UC) patients,and 779 healthy *** ratio(OR) and 95%CI were estimated by logistic regression models. RESULTS:The PXR A7635G variant,the PPARγPro12Ala and LXR T-rs2695121-C homozygous variant genotypes were associated with risk of UC(OR:1.31,95% CI:1.03-1.66,P=0.03,OR:2.30,95%CI:1.04-5.08,P=0.04,and OR:1.41,95%CI:1.00-1.98,P=0.05,respectively) compared to the corresponding homozygous wild-type *** never smokers,PXR A7635G and the LXR T-rs1405655-C and T-rs2695121-C variant genotypes were associated with risk of IbD(OR:1.41,95%CI:1.05-1.91,P=0.02,OR:1.63,95%CI:1.21-2.20,P=0.001,and OR:2.02,95%CI:1.36-2.99,P=0.0005,respectively) compared to the respective homozygous variant *** A7635G(rs6785049) variant genotype was associated with a higher risk of UC diagnosis before the age of 40 years and with a higher risk of extensive disease(OR:1.34,95%CI:1.03-1.75 and OR:2.49,95%CI:1.24-5.03,respectively) . CONCLUSION:Common PXR and LXR polymorphisms may contribute to risk of IbD,especially among never smokers.

关键词： Crohn's disease Genetic susceptibility Single nucleotide polymorphisms Smoking status Transcription factors Ulcerative colitis