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Analysis of.temporal changes in land cover and landscape metrics of.a managed f.rest in the west Black Sea region of.northern Turkey: 1970–2010

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Journal of.f.restry Research 2018年第1期29卷 139-150页

作者： Hayati Zengin Ahmet Salih Degermenci Pete bettinger Department of.f.rest Management and Planning Faculty of Forestry Duzce University Warnell School of.f.restry and Natural Resources University of Georgia

f.rest structure changes continuously by natural and anthropogenic ef.ects. Because the level of.goods and services provided by f.rest ecosystems are related to this structure, some attributes have to be controlled while they are being managed. In this paper we describe the long-term temporal changes in land area and landscape metrics related to dif.erent land uses of.a managed f.rest in Turkey. The study was carried out f.r the Daday f.rest Planning Unit located in the west Black Sea region of.northern Turkey. The total area is 16,813 ha and besides wood production, it is managed f.r erosion control, public health, aesthetics, and recreation. Stand type maps that were constructed in 1970,1989, 1999, and 2010 were used in this analysis. Transition matrixes that illustrate area changes among cover types and temporal changes on some landscape metrics were obtained using Geographic Inf.rmation Systems. Stands were separated into small patches, and thus the number of.patches increased nearly two-f.ld between 1970 and 2010. The total f.rest edge increased and through the associated f.agmentation, the amount of.core f.rest area decreased at the landscape scale. Landscape metrics were applied to digitized versions of.historical maps to assess how f.rest area changed. Human use of.the land has changed, f.rest management practices have evolved, and these along with natural f.rest growth have contributed to interesting changes in landscape character.

关键词： Landscape metrics Land cover change Temporal change Turkey

Edible hybrid microbial-electronic sensors f.r bleeding detection and beyond

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Hepatobiliary Surgery and Nutrition 2019年第2期8卷 157-160页

作者： Christopher J.bettinger Department of.Materials Science and Engineering Carnegie Mellon UniversityPittsburghPAUSA Department of.Biomedical Engineering Carnegie Mellon UniversityPittsburghPAUSA

Introduction to edible electronics Edible electronic devices are orally deployable electrif.ed medical devices that have great potential to diagnose and treat many types of.*** in edible electronic devices has accelerated in recent years f.r several ***,the role of.gut health on overall health is becoming *** composition inf.uences metabolism,immunity,and cognitive *** gut microbiome is also a valuable biomarker f.r distinguishing between healthy and diseased *** and longitudinal surveillance may could detect disorders such as inf.ammatory bowel disease(IBD),Crohn's disease,colorectal cancer,or ***,the availability of.computing platf.rms and genomic inf.rmation are becoming more prevalent,cost-ef.ective,and *** and low-cost electronics serve as a core technology f.r designing and f.bricating edible electronic *** computing platf.rms can provide a complementary monitoring network to interrogate ingestible medical devices in ambulatory ***,there have been critically enabling advances in materials,non-conventional f.brication,and device ***,Mimee et *** many of.these capabilities to create an edible electronic device to detect bleeding in clinically relevant animal *** key innovation is the use of.genetically engineered bacteria that transduce biochemical markers f.r bleeding into optical signals that can be measured,quantif.ed,recorded,and communicated to external devices outside the body.

关键词： metabolism immunity becoming

Mixed-ef.ects modeling f.r tree height prediction models of.Oriental beech in the Hyrcanian f.rests

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Journal of.f.restry Research 2018年第5期29卷 1195-1204页

作者： Siavash Kalbi Asghar f.llah Pete bettinger Shaban Shataee Rassoul Yousef.our Sari Agriculture and Natural Resource University SariMazandaran Iran Warnell School of.f.restry and Natural Resources University of Georgia Athens GA USA Gorgan Agriculture and Natural Resource University Gorgan Golestan Iran f.culty of.Environment and Natural Resources University of Freiburg Freiburg Germany

Height–diameter relationships are essential elements of.f.rest assessment and modeling *** this work,two linear and eighteen nonlinear height–diameter equations were evaluated to f.nd a local model f.r Oriental beech（f.gus orientalis Lipsky） in the Hyrcanian f.rest in *** predictive perf.rmance of.these models was f.rst assessed by dif.erent evaluation criteria： adjusted R^2（R^2_（adj））,root mean square error（RMSE）,relative RMSE（%RMSE）,bias,and relative bias（%bias） *** best model was selected f.r use as the base mixed-ef.ects *** parameters f.r test plots were estimated with dif.erent tree selection *** show that the Chapman–Richards model had better predictive ability in terms of.adj R^2（0.81）,RMSE（3.7 m）,%RMSE（12.9）,bias（0.8）,%Bias（2.79） than the other ***,the calibration response,based on a selection of.f.ur trees f.om the sample plots,resulted in a reduction percentage f.r bias and RMSE of.about 1.6–2.7%.Our results indicate that the calibrated model produced the most accurate results.

关键词： Random ef.ects Tree height Calibration Sangdeh f.rest Chapman–Richards model Oriental beech

f.rmation and Microstructural Characterization of.Silicon-modif.ed Aluminide Coating on Nickel-based Superalloy IN738LC

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材料热处理学报 2004年第05B期25卷 657-660页

作者： f. Shahriari f. Ashraf.zadeh A. Monshi Materials engineering department Isfahan University of Technology Isfahan IranMaterials engineering department Isfahan University of Technology Isfahan IranMaterials engineering department Isfahan University of Technology Isfahan Iran

In this investigation, aluminide coatings used to protect industrial components at high temperature and corrosive environments were modif.ed with silicon addition and the microstructural f.atures and f.rmation mechanism were evaluated. The coating on the nickel-based superalloy IN738LC was carried out by a two stage process including siliconizing at f.rst and aluminizing thereaf.er. Pack cementation siliconizing perf.rmed at 950C f.r 2, 4 and 6 hours in several powder mixtures of.Si, A12O3 and NHiCl, then aluminum was dif.used into the surf.ce of.the specimens by an industrial aluminizing process. The modif.ed coatings were characterized by means of.standard metallography, scanning electron microscopy, energy dispersive spectroscopy and X-ray dif.raction methods. The results show that Si in the coatings mainly presents in the f.rm of.secondary phases including Cr3Si, Mo5Si3 and Nii6Ti6Si7, well distributed within the NiAl matrix. The advantages of.this two stage modif.ed coating is discussed.

关键词：显微结构 IN738LC 镍超级合金扩散渗碳处理生长机制

Closed-f.rm solutions f.r f.ee vibration of.rectangular f.M thin plates resting on elastic f.undation

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Acta Mechanica Sinica 2016年第6期32卷 1088-1103页

作者： T. f. Xu Y. f. Xing Institute of.Solid Mechanics Beihang UniversityBeijing 100191 China China Academy of.Launch Vehicle Technology R&D Center Beijing 100076 China

This article presents closed-f.rm solutions f.r the f.equency analysis of.rectangular f.nctionally graded material (f.M) thin plates subjected to initially in-plane loads and with an elastic f.undation. Based on classical thin plate theory, the governing dif.erential equations are derived using Hamilton's principle. A neutral surf.ce is used to eliminate stretching-bending coupling in f.M plates on the basis of.the assumption of.constant Poisson's ratio. The resulting governing equation of.f.M thin plates has the same f.rm as homogeneous thin plates. The separation-of.variables method is adopted to obtain solutions f.r the f.ee vibration problems of.rectangular f.M thin plates with separable boundary conditions, including, f.r example, clamped plates. The obtained normal modes and f.equencies are in elegant closed f.rms, and present f.rmulations and solutions are validated by comparing present results with those in the literature and f.nite element method results obtained by the authors. A parameter study reveals the ef.ects of.the power law index n and aspect ratio a/b on f.equencies.

关键词： f.nctionally graded material f.ee vibration Rectangular plate Close f.rm solutions Neutral surf.ce

Phylogenetic reconstruction of.Chirita and allies (Gesneriaceae) with taxonomic treatments

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Journal of.Systematics and Evolution 2011年第1期49卷 50-64页

作者： James f. SMITH Department of.Biological Sciences Boise State University

Chirita D. Don, a large genus in the subf.mily Cyrtandroideae of.Gesneriaceae, has been the subject of.much debate whether it is a natural group or not. In addition, the highly heterogeneous Chirita has also been very problematic with regard to delimitation and subdivision. Here we used the nrDNA internal transcribed spacer and cpDNA trnL-f.f.r molecular phylogenetic analaysis, combined with morphological data. Our results suggest that Chirita is an artif.cial, polyphyletic genus. The most important character that def.nes Chirita, the dorso-ventrally oblique and bilamellar stigma, has evolved convergently in dif.erent clades of.diandrous Cyrtandroideae. Chirita sensu stricto only includes the species of.Chirita sect. Chirita, whereas Chirita sect. Microchirita is an independent clade located at the basal node of.the phylogenetic tree. Chirita sect. Liebigia is closely related to Didymocarpus with an entire stigma unlike other species of.Chirita. The species of.Chirita sect. Gibbosaccus, Chiritopsis, Primulina, and Wentsaiboea f.rm a monophyletic group that is sister to a strongly supported clade comprising f.ur monotypic genera Paralagarosolen, Calcareoboea, Petrocodon, and Tengia. We f.rther analyzed the morphological evolution of.Chirita and identif.ed a series of.morphological synapomorphies f.r the monophyletic groups revealed herein, and thereby provide a taxonomic treatment in this study.

关键词： Chirita D. Don morphological evolution phylogenetic reconstruction polyphyly taxonomic treatment.

Regulation of.gene-edited plants in Europe:f.om the valley of.tears into the shining sun?

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aBIOTECH 2024年第2期5卷 231-238页

作者： holger Puchta Department of.Molecular Biology Joseph Gottlieb Kolreuter Institute for Plant SciencesKarlsruhe Institute of Technology(KIT)Fritz-Haber-Weg 476131 KarlsruheGermany

Some 20 years ago,the EU introduced complex regulatory rules f.r the growth of.transgenic crops,which resulted in a de f.cto ban to grow these plants in f.elds within most European *** the rise of.novel genome editing technologies,it has become possible to improve crops genetically in a directed way without the need f.r incorporation of.f.reign ***,in 2018,the European Court of.Justice ruled that such gene-edited plants are to be regulated like transgenic *** then,European scientists and breeders have challenged this decision and requested a revision of.this outdated ***,af.er 5 years,the European Commission has now published a proposal on how,in the f.ture,to regulate crops produced by new breeding *** proposal tries to f.nd a balance between the dif.erent interest groups in *** one side,genetically modif.ed plants,which cannot be discerned f.om their natural counterparts,will exclusively be used f.r f.od and f.ed and are-besides a registration step-not to be regulated at *** the other side,plants expressing herbicide resistance are to be excluded f.om this regulation,a concession to the strong environmental associations and NGOs in ***,edited crops are to be excluded f.om organic f.rming to protect the business interests of.the strong organic sector in ***,if.this law passes European parliament and council,unchanged,it will present a big step f.rward toward establishing a more sustainable European agricultural ***,it might soon be possible to develop and grow crops that are more adapted to global warming and whose cultivation will require lower amounts of.***,there is still a long way to go until the law is *** of.en,the storm of.arguments raised by the opponents,based on irrational f.ars of.mutations and a naive understanding of.nature,has f.llen on f.uitf.l ground in Europe.

关键词： Genetically modif.ed organism Cisgenesis Gene editing CRISPR/Cas Regulation

Nanoscale displacement of.the image of.an atomic source of.radiation

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Chinese Optics Letters 2009年第2期7卷 149-151页

作者： Henk f. Arnoldus Department of.Physics and Astronomy Mississippi State University

Light emitted by an atomic source of.radiation appears to travel along a straight line （ray） f.om the location of.the source to the observer in the f.r f.eld. However, when the energy f.ow pattern of.the radiation is resolved with an accuracy better than an optical wavelength, it turns out that the f.eld lines are usually curved. We consider electric dipole radiation, a prime example of.which is the radiation emitted by an atom during an electronic transition, and we show that the f.eld lines of.energy f.ow are in general curves. Near the location of.the dipole, the f.eld lines exhibit a vortex structure, and in the f.r f.eld they approach a straight line. The spatial extension of.the vortex in the optical near f.eld is of.nanoscale dimension. Due to the rotation of.the f.eld lines near the source, the asymptotic limit of.a f.eld line is not exactly in the radially outward direction and as a consequence, the image in the f.r f.eld is slightly shif.ed. This sub-wavelength displacement of.the image of.the source should be amenable to experimental observation with contemporary nanoscale-precision techniques.

关键词： Atoms Electric dipole moments f.ow patterns Nanotechnology Vortex f.ow

Inf.uence of.Processing Parameters on the Strength of.Air Brazed Alumina Joints Using Aluminium Interlayer

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Journal of.Materials Science & Technology 2011年第7期27卷 641-646页

作者： A. Ibrahim f. Hasan Department of.Metallurgical and Materials Engineering University of Engineering and TechnologyLahore Pakistan

Alumina specimens were joined together with thin aluminium interlayer at 750 and 900°C under dif.erent applied pressures and holding time in air. f.exural strength of.the joints was then measured using a standard f.ur-point bend test method. Characterization of.the interf.ce was carried out to correlate the increase in f.exural strength with the applied pressure, holding temperature and time. The study showed that the strength of.joint is af.ected by all three parameters, i.e., processing temperature, holding time as well as applied pressure.

关键词： Pressure-assisted air brazing Alumina Aluminum Brazing Joining and Ceramic