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Charcoal production through selective logging leads to degradation of dry woodlands:a case study from Mutomo district,Kenya

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Journal of Arid Land 2016年第4期8卷 618-631页

作者： Geoffrey M NdEGWA Udo NEHREN Friederike GRüNINGER Miyuki IIYAMA dieter ANHUF department of Physical Geography University of PassauPassau 4094036Germany Institute for Technology and Resources Management in the Tropics and Subtropics TH Ko1n University of Applied SciencesCologne 250679Germany The World Agroforestry Centre Nairobi 30677-00100Kenya The Japan I-nternational Research Center for Agricultural Sciences(JIRCAS)1-1 Owashi Tsukubalbaraki Prefecture 305-0851Japan

Provision of woodfuel is an important ecosystem service of dry forests and woodlands. However, charcoal production through selective logging of preferred hardwood species has the potential to alter the physiognomic composition of the residual or re-growth woodlands and may lead to their deterioration and degradation. This study, conducted through forest inventory in Mutomo district in Kenya, assessed the impact of charcoal production on unprotected dry woodlands in terms of tree density, targeted species basal area, species richness, evenness and Shannon diversity. The parameters of the disturbed woodlands were evaluated for significant differences with those of the neighbouring protected Tsavo East National Park, which served as a reference for an ecologically undisturbed ecosystem. By evaluating a consequence of tree harvesting for charcoal production, this study confirmed the overall significant differences between the protected and unprotected woodlands in all the tested parameters. To confirm if the differences in the land-covers of the woodlands had any influence on their degradation, all mentioned parameters were compared between the four differentiated classes and their respective control plots in the protected areas. At the ＂land-cover level＂, the statistically significant difference in the basal area of tree species preferred for charcoal production between the protected and unprotected open trees confirms that the class with a high density of large mature trees is the prime target of charcoal producers. In addition, there seems to be a general trend of lower values of tree species richness, evenness and Shannon diversity for the unprotected woodlands subjected to charcoal production. On the other hand, the disturbed woodlands display the potential to recover through their comparably high saplings density. The findings make an important contribution to the discourse on the impact of charcoal production in dry woodlands, a topic that is highly controversial

关键词： charcoal burning forest degradation selective harvesting Acacia-Commiphora bushland coppicing

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A Cambrian micro-lobopodian and the evolution of arthropod locomotion and reproduction

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Chinese Science Bulletin 2007年第24期52卷 3385-3392页

作者： Andreas Maas Georg Mayer Reinhardt M. Kristensen dieter Waloszek Section for Biosystematic documentation University of Ulm Helmholtzstrasse 20 D-89081 Ulm Germany department of Anatomy and Cell Biology University of Melbourne Victoria Australia 3010 Zoological Museum University of Copenhagen 15 Universitetsparken DK-2100 Copenhagen Denmark

The evolutionary success of arthropods, the most abundant and diverse animal group, is mainly based on their segmented body and jointed appendages, features that had evolved most likely already before the Cambrian. The first arthropod-like animals, the lobopodians from the Early Cambrian, were unsclerotized and worm-like, and they had unjointed tubular legs. Here we describe the first three-dimensionally preserved Cambrian lobopodian. The material presented of Orstenotubulus evamuellerae gen. et sp. nov. is the smallest and youngest of a lobopodian known. O. evamuellerae shows strikingly detailed similarities to Recent tardigrades and/or onychophorans in its cellular-structured cuticle and the telescopic spines. It also shows similarities to other, longer known lobopodians, but which are ten times as large as the new form. These similarities include the finely annulated body and legs, which is characteristic also for Recent onychophorans, and paired humps continuing into spines situated dorsally to the leg insertions, a feature lacking in the extant forms. The morphology of O. evamuellerae not only elucidates our knowledge about lobopodians, but also aids in a clearer picture of the early evolution of arthropods. An example is the single ventral gonopore between a limb pair of O. evamuellerae, which indicates that a single gonopore, as developed in onychophorans, tardigrades, pentastomids, myriapods and insects, might represent the plesiomorphic state for Arthropoda, while the paired state in chelicerates and crustaceans was convergently achieved. Concerning life habits, the lateral orientation of the limbs and their anchoring spines of the new lobopodian imply that early arthropods were crawlers rather than walkers.

关键词：寒武纪节足动物门进化发展史生殖系统移动力

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Between Scylla and Charybdis:The role of the human immune system in the pathogenesis of hepatitis C

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World Journal of Gastroenterology 2013年第44期19卷 7852-7866页

作者： Ulrich Spengler Hans dieter Nischalke Jacob Nattermann Christian P Strassburg department of Internal Medicine 1 University of Bonn 53105 Bonn Germany

Hepatitis C virus(HCV)frequently elicits only mild immune responses so that it can often establish chronic *** this case HCV antigens persist and continue to stimulate the immune *** persistence then leads to profound changes in the infected host’s immune responsiveness,and eventually contributes to the pathology of chronic *** topic highlight summarizes changes associated with chronic hepatitis C concerning innate immunity(interferons,natural killer cells),adaptive immune responses(immunoglobulins,T cells,and mechanisms of immune regulation(regulatory T cells).Our overview clarifies that a strong anti-HCV immune response is frequently associated with acute severe tissue *** chronic hepatitis C,however,the effector arms of the immune system either become refractory to activation or take over regulatory *** together these changes in immunity may lead to persistent liver damage and ***,effector arms of the immune system will not only be considered with respect to antiviral defence but also as pivotal mechanisms of inflammation,necrosis and progression to ***,avoiding Scylla-a strong,sustained antiviral immune response with inital tissue damage-takes the infected host to virus-triggered immunopathology,which ultimately leads to cirrhosis and liver cancerthe realm of Charybdis.

关键词： Natural killer cells Cd4+ T helper cells Regulatory T cells Interferon Hepatitis C Hepatic stellate cells Hepatocytes Immunoglobulin Retinoic acid inducible gene-I Toll like receptors

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MAPPING THE dAMAGEd ZONE AROUNd THE CRACK TIP IN HIGH dENSITY POLYETHYLENE WITH SYNCHROTRON MICROFOCUS SMALL ANGLE X-RAY SCATTERING TECHNIQUE

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Chinese Journal of Polymer Science 2010年第2期28卷 165-170页

作者： Hans-Friedrich Enderle dieter Lilge Stephan V.Roth Rainer Gehrke Jens Rieger 门永锋 Basell Polyolefine GmbH R&D65926 FrankfurtGermany HASYLAB am dESY Notkestr.8522607 HamburgGermany BASF SE Polymer Research67056 LudwigshafenGermany State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of Sciences

The structural changes around a crack tip in a high density polyethylene were investigated by means of scanning synchrotron microfocus small-angle X-ray scattering technique. The scattering data confirm the process of craze structure development near a crack tip based on the evolution of voids. In addition, it was found that the main stress in the plastic zone near a crack tip exhibited a gradient distribution with respect to its strength and direction. The whole damaged area showed a strain distribution indicating a flow behavior toward the crack tip.

关键词： High density polyethylene Microfocus SAXS Crack tip Voids.

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Wheat yield convergence and its driving factors in countries along the Belt and Road

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Ecosystem Health and Sustainability 2020年第1期6卷 709-723,708页

作者： Xiaoheng Zhang Zhina Wang Ping Qing dieter Koemle Xiaohua Yu College of Economics and Management Huazhong Agricultural UniversityWuhanP.R.China Leibniz-Institute of Freshwater Ecology and Inland Fisheries(IGB) BerlinGermany department of Agricultural Economics and Rural development University of GottingenGöttingenGermany

Improving the wheat yield of countries along the Belt and Road(BR)plays a core role in ensuring global food ***,little attention has been paid to the wheat yield variation and the determinants across these *** paper analyzes wheat yield convergence in countries along the BR using the club-convergence *** empirical results show that instead of one convergence for all countries along the BR,the wheat yields are converging into three ***,we investigate the impact of climate change and agricultural production technology on wheat yield convergence,and find that countries along the BR with a one degree Celsius increase in temperature are 36.5%(32.7%)more likely to converge to the high-level yield *** may be related to the lower frequency of frost and higher photosynthetic capacity of *** also find that a one kilogram increase in fertilizer application per hectare will result in a 0.4%(0.5%)higher probability of countries along the BR converging to the high-level yield *** along the BR should pay more attention to coordinating production technologies and climate change to ensure food security.

关键词： Club convergence countries along the BR wheat yield temperature intensity of fertilizer use

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Problems of drinking water treatment along Ismailia Canal Province, Egypt

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第3期9卷 232-242页

作者： Mohamed H.GERIESH Klaus-dieter BALKE Ahmed E.EL-RAYES Geology department Faculty of ScienceSuez Canal UniversityP.C.41522IsmailiaEgypt Institute of Geosciences Teubingen University72076 TeubingenGermany

The present drinking water purification system in Egypt uses surface water as a raw water supply without a preliminary filtration *** the other hand,chlorine gas is added as a disinfectant agent in two steps,pre-and *** to these reasons most of water treatment plants suffer low filtering effectiveness and produce the trihalomethane(THM) species as a chlorination *** Ismailia Canal represents the most distal downstream of the main Nile *** its water contains all the proceeded pollutants discharged into the *** addition,the downstream reaches of the canal act as an agricultural drain during the closing period of the High dam gates in January and February every ***,the wide industrial zone along the upstream course of the canal enriches the canal water with high concentrations of heavy *** obtained results indicate that the canal gains up to 24.06×106 m3 of water from the surrounding shallow aquifer during the closing period of the High dam gates,while during the rest of the year,the canal acts as an influent stream losing about 99.6×106 m3 of its water *** reduction of total organic carbon(TOC) and suspended particulate matters(SPMs) should be one of the central goals of any treatment plan to avoid the disinfectants *** combination of sedimentation basins,gravel pre-filtration and slow sand filtration,and underground passage with microbiological oxidation-reduction and adsorption criteria showed good removal of parasites and bacteria and complete elimination of TOC,SPM and heavy ***,it reduces the use of disinfectants chemicals and lowers the treatment ***,this purification system under the arid climate prevailing in Egypt should be tested and modified prior to application.

关键词： drinking water treatment Hazardous by-products Natural attenuation Ismailia Canal Egypt

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The Impact of Brand Loyalty on Variables Influencing Customer Satisfaction and Online Reviews in the Hospitality Industry

The Impact of Brand Loyalty on Variables Influencing Custome...

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作者： Maximilian dieter Wolfgang Busse 上海交通大学

学位级别：硕士

The purpose of this paper is to investigate the diverging expectations of customer groups in the hospitality industry based on loyalty towards a *** the aim to understand how these expectations and attitudes transform,this paper utilizes user-generated content from more than 5000 unique online reviews of 14 hotels around New York Times Square sourced from ***.A research framework proposes a direct positive relationship between the six independent variables(Cleanliness,dining,Location,Service,Amenities,Value for the Money)assessed in the online reviews and the dependent variable ‘Total Score'.Furthermore,four levels of loyalty(No,Low,Medium,High)are assumed to be moderators of these *** research findings suggest that ‘Service' is the strongest predictor of the dependent variable,followed by ‘Value for the Money'.‘dining' is the only factor that fails to moderate the ‘Total Score' for the customer groups with loyalty levels of Medium and ***,a content-based analysis supports the crucial findings revealed by the *** results of this paper emphasize the significance of loyalty and its impact on satisfaction while providing valuable suggestions to find strategies supporting the production of positive user-generated content and stimulating e-Word-of-Mouth.

关键词： Brand Loyalty Consumer Behavior Hospitality Industry User-Generated Content e-Word-of-Mouth

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A phylogeographic break and bioacoustic intraspecific differentiation in the Buff-barred Warbler(Phylloscopus pulcher)(Aves:Passeriformes,Phylloscopidae)

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Chinese Birds 2014年第1期5卷 3-14页

作者： Martin Packert Yue-Hua Sun Balduin S Fischer dieter Thomas Tietze Jochen Martens Senckenberg Natural History Collections Museum of ZoologyKonigsbrücker Landstraβe 159D-01109 DresdenGermany Key Laboratory of Animal Ecology and Conservation Institute of ZoologyChinese Academy of Science Institute of Ecology Evolution and DiversityGoethe UniversityMax-von-Laue-Straβe 1360439 Frankfurt am MainGermany Institute of Pharmacy and Molecular Biotechnology University of HeidelbergIm Neuenheimer Feld 36469120 HeidelbergGermany Institut für Zoologie Johannes Gutenberg-Universitat55099 MainzGermany

Background: According to current taxonomy only three out of 27 Sinohimalayan leaf warbler species(Phylloscopidae) are considered genetically uniform across their entire breeding range along the Southeastern margin of the Qinghai-Tibetan Plateau, the Buff-barred Warbler(Phylloscopus pulcher) being one of them. Because marked differentiation among Himalayan and Chinese populations has been recently demonstrated for a number of Phylloscopus species(or sister species) we investigated the intraspecific variation of a mitochondrial gene, songs and morphology of P. pulcher in a phylogeographic ***: We sequenced a fragment of the mitochondrial cytochrome b, reconstructed haplotype networks and analyzed dNA polymorphism among Himalayan and Chinese populations. We measured time and frequency parameters of two distinct song types and analyzed among population-differentiation in a principal component analysis and a discriminant analysis. We also compared measurements of body size dimensions taken from museum ***: The mitochondrial haplotype network(cytb) was divided into two distinct clusters corresponding to geographic origin of samples. Pairwise genetic distances among Himalayan and Chinese mt dNA lineages account for 1.3% which coincides with Pleistocene lineage separation at roughly 650,000 years ago. Genetic diversity is slightly higher in the Chinese part of the species' range with respect to haplotype and nucleotide diversity while the less diversified Himalayan population lineage shows signs of recent range expansion. The vocal repertoire of P. pulcher comprises two distinct verse types that are combined with short interspersed click notes to long continuous song displays. Trill verse types showed significant differences among regions in almost all measured frequency and time parameters: Chinese males displayed more rapid and more broad-banded trills at a lower pitch. In contrast,warbling verse types showed a distinctively different structure

关键词： Phylloscopidae Phylogeography East–west divide Territorial songs Phylloscopus pulcher vegetus

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Modeling hydraulic fracture in heterogeneous rock materials using permeability-based hydraulic fracture model

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Underground Space 2020年第2期5卷 167-183页

作者： Ming Li Peijun Guo dieter F.E.Stolle Li Liang Yitao Shi department of Civil Engineering Northeastern UniversityBox 265 N3-11Wenhua RoadHeping DistrictShenyang 110819PR China department of Civil Engineering McMaster University1280 Main Street WestHamiltonOntario L8S 4L8Canada

Hydraulic fracturing is one of the most important techniques for enhancing oil/gas *** permeability-based hydraulic fracture(PHF)model,which is based on the smeared-crack method and considers the interaction between the pore pressure and solid phase,is adopted in the present study for a fully-coupled simulation of the hydraulic fracture in a heterogeneous rock *** level set method(LSM),which is used to describe the distribution of material properties of heterogeneous rocks,is coupled with the PHF *** the coupled PHF–LSM model,a series of finite element method(FEM)simulations are carried out to investigate the characteristics of a hydraulic fracture(e.g.,the breakdown pressure and fracture propagation)in heterogeneous *** types of heterogeneous rocks are examined:layered rock,rock with distributed inclusions,and rock with random spatial variations in the material *** results of the numerical simulations show that the coupled PHF–LSM model can describe the material interface without changing the FEM mesh used to discretize the physical ***,the model effectively simulates hydraulic-fracturing problems for various heterogeneous rocks.

关键词： Hydraulic fracture Heterogeneous rock material Smeared-crack method Level set method

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PET imaging in ischemic cerebrovascular disease:current status and future directions

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Neuroscience Bulletin 2014年第5期30卷 713-732页

作者： Wolf-dieter Heiss Max Planck Institute for Neurological Research

Cerebrovascular diseases are caused by interruption or significant impairment of the blood supply to the brain, which leads to a cascade of metabolic and molecular alterations resulting in functional disturbance and morphological damage. These pathophysiological changes can be assessed by positron emission tomography （PET）, which permits the regional measurement of physiological parameters and imaging of the distribution of molecular markers. PET has broadened our understanding of the flow and metabolic thresholds critical for the maintenance of brain function and morphology： in this application, PET has been essential in the transfer of the concept of the penumbra （tissue with perfusion below the functional threshold but above the threshold for the preservation of morphology） to clinical stroke and thereby has had great impact on developing treatment strategies. Radioligands for receptors can be used as early markers of irreversible neuronal damage and thereby can predict the size of the final infarcts; this is also important for decisions concerning invasive therapy in large （＂malignant＂） infarctions. With PET investigations, the reserve capacity of blood supply to the brain can be tested in obstructive arteriosclerosis of the supplying arteries, and this again is essential for planning interventions. The effect of a stroke on the surrounding and contralateral primarily unaffected tissue can be investigated, and these results help to understand the symptoms caused by disturbances in functional networks. Chronic cerebrovascular disease causes vascular cognitive disorders, including vascular dementia. PET permits the detection of the metabolic disturbances responsible for cognitive impairment and dementia, and can differentiate vascular dementia from degenerative diseases. It may also help to understand the importance of neuroinflammation after stroke and its interaction with amyloid deposition in the development of dementia. Although the clinical application of PET

关键词： stroke dementia PET brain metabolism brain ischemia

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