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Distribution of stem decay in the beech trees of the Azerbaijan and its impact on the output of commercial wood

Journal of Forestry Research 2019年第3期30卷 1023-1028页

作者： A.b.Yakhyaev V.S.Farzaliyev e.P.Safarova Azerbaijan University of Architecture and Construction Mammad Rahim StreetBaku City 1004Azerbaijan Republic Central botanical Garden of Azerbaijan National Academy of Sciences Mikayil Mushfig 103Baku City 1004 Azerbaijan Republic

To determine the distribution of stem decay in the beech stands of Azerbaijan, we sought to identify the species, number, and height of attachment of fruiting bodies;the extent of decay in tree trunks growing under different conditions;and its influence on the trees’ commercial wood. The research was conducted on three farms representing the most common forest types of the Greater Caucasus within Azerbaijan. examination of the presence of fruiting bodies in the tree trunk revealed that stem decay is the most common infection in beech (Fagus orientalis) stands, especially in fresh, moist areas, with less infection under dry growing conditions. In this work, the length, diameter, and volume of decay were studied by infecting the trunks of 93 model trees affected with mushrooms in 1–4 m cuttings. Our results showed that as the age of the stand increased, extent, diameter, and volume of decay increased significantly: the extent of decay from 1.47 to 6.43 m;the diameter of the decay from 8.15 to 32.7 cm;and the volume of decay from 2.5 to 13.2%. The relationship between age and the specified indicators is presented graphically. Using data obtained from the same sample of trees, we determined the expected and actual yield of commercial wood by age class. We determined that stem decay in beech stands leads to a decrease in the yield of commercial wood on average from 25.1% in the middle-aged to 14.8% in overmature plantations, respectively, with an estimated yield of 40.8–62.7%. Here we present mathematical models of the output of commercial wood from the infected part of the stands by age classes with the use of average data on the extent of decay in model trees.

关键词： beech Wood Infection Forest type Stem decay Output of commercial wood Fruiting bodies

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DeM Fusion using a modified k-means clustering algorithm

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International Journal of Digital earth 2016年第12期9卷 1242-1255页

作者： Colleen e.Fuss Aaron A.berg John b.Lindsay Department of Geography University of GuelphGuelphCanada

Digital elevation models(DeMs)are a necessary dataset for modelling the earth’s surface;however,all DeMs contain *** can reduce this error using DeM fusion techniques since numerous DeMs can be available for a ***,the use of a clustering algorithm in DeM fusion has not been previously *** this study a new DeM fusion algorithm based on a clustering approach that works on multiple DeMs to exploit consistency in the estimates as indicators of accuracy and precision is *** fusion approach includes slope and elevation thresholding,k-means clustering of the elevation estimates at each cell location,as well as filtering and smoothing of the fusion *** of the input DeMs,and the products of each step of the fusion algorithm,with a higher accuracy reference DeM enabled a detailed analysis of the effectiveness of the DeM fusion *** main findings of the research were:the k-means clustering of the elevations reduced the precision which also impacted the overall accuracy of the estimates;the number of final cluster members and the standard deviation of elevations before clustering both had a strong relationship to the error in the k-means estimates.

关键词： DeM fusion k-means clustering DeM error

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ALTeRATIONS IN AUTOFLUOReSCeNCe SIGNAL FROM RAT SKIN eX VIVO UNDeR OPTICAL IMMeRSION CLeARING

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Journal of Innovative Optical Health Sciences 2010年第3期3卷 147-152页

作者： e.V.MIGACHeVA A.b.PRAVDIN V.V.TUCHIN Saratov State University 83 Astrakhanskaya str.410012 SaratovRussia

For the first time,the changes in autofluorescence spectra of ex vivo rat skin have been experimentally investigated using the combination of fluorescence spectroscopy and optical immersion *** glucose,glycerol and propylene glycol solutions were used as clearing *** optical clearing was performed from the dermal side of skin imitating the in vivo injection of clearing agent under the dermal *** this contribution,the common properties of autofluorescence variation during optical immersion clearing were *** tendency of autofluorescence signal to decrease with reduction of scattering in tissue was noticed and discussed in ***,the differences in the shape of spectral curves under application of different clearing agents showed that optical clearing affects the autofluorescence properties of tissue differently depending on the type of clearing *** results obtained are useful for the understanding of tissue optical clearing mechanisms and for improving techniques such as fluorescence spectroscopy.

关键词： Autofluorescence spectra fluorescence spectroscopy rat skin tissue optical clearing clearing agents

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Miniaturized antenna design for communication establishment of peer-to-peer communication in the oil pipelines

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Petroleum Research 2021年第3期6卷 291-302页

作者： e.b.Priyanka S.Thangavel T.Kalavathidevi Department of Automobile engineering Kongu Engineering CollegeErode638060India Department of Mechatronics engineering Kongu Engineering CollegeErode638060India Department of electronics and Instrumentation engineering Kongu Engineering CollegeErode638060India

In the oil pipeline world,wireless automation plays an important role through integrated electronic technology in antenna design for robust *** technology gets evaluated by its power consumption and compactness to afford a better solution to real-world problems with better sophistication to adopt a modernized wireless *** that,the IoT(Internet of Things)technology plays a predominant role by combining with Artificial Intelligence to optimize and revolute the characterization of data *** the data communication is initiated,the main contributor to the transmission is the miniaturized antenna holding different types in its structure and *** acquires the required radio spectrum channel with the advanced multi coding modulating technique by utilizing token ring mesh topology for the data transfer with acquired data *** chapter describes the design and fabrication of a miniaturized antenna using MeMS technology(Micro-electro-Mechanical System)and its different types using INTeLLISUITe software to get suited for better communication in oil *** on the application,it also enumerates the choices of micro or nanoantennas with its specification upholding data adopting techniques with modulation schemes to support IoT applications.

关键词： Antenna MeMS Channel width Optimization Oil pipelines and IoT

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bound in continuum states and induced transparency in mesoscopic demultiplexer with two outputs

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Chinese Physics b 2020年第12期29卷 429-437页

作者： Z Labdouti T Mrabti A Mouadili e H el boudouti F Fethi b Djafari-Rouhani LPMR Dèpartement de PhysiqueFacultèdes SciencesUniversitèMohammed IOujdaMorocco LSTA Dèpartement de PhysiqueFacultèPolydisciplinaire de LaracheUniversitèAbdelmalek EssaadiTètouanMorocco LPMCeR Dèpartement de PhysiqueFacultèdes Sciences et Techniques de MohammediaUniversitèHassan IICasablancaMorocco IeMN UMR CNRS 8520UFR de PhysiqueUniversitède Lille59655 Villeneuve d'AscqFrance

We investigate the electronic transport in a simple mesoscopic cross structure made of two wires(stubs)grafted at the same point along a quantum *** show that the structure may exhibit important phenomena such as bound in continuum(bIC)*** states are transformed into electromagnetically induced transparency(eIT)resonance by detuning slightly the lengths of the *** last phenomenon is used to propose and study a mesoscopic demultiplexer device with an input waveguide and two output *** give closed-form expressions of the geometrical parameters that allow a selective transfer of a given state in the first waveguide without perturbing the second *** effect of temperature on the transmission resonances is also examined by using Landauer-büttiker *** analytical results of the dispersion relation and transmission and reflection coefficient are obtained using the Green's function method.

关键词： mesoscopic structure demultiplexer device bound states in continuum(bIC) eIT resonance

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Logging and topographic effects on tree community structure and habitat associations in a tropical upland evergreen forest,Ghana

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Journal of Forestry Research 2021年第4期32卷 1361-1372页

作者： P.Addo-Fordjour e.K.boakye Z.b.Rahmad Department of Theoretical and Applied biology College of ScienceKwame Nkrumah University of Science and TechnologyKumasiGhana School of biological Sciences Universiti Sains Malaysia11800 USM Pulau PinangMalaysia

We determined the response of tree community structure to logging disturbance and topography,and the patterns of tree-habitat associations in Tano Offin Forest Reserve,*** sampled trees in 27 20 m× 20 m plots randomly and equally distributed in three topographic habitats(slope,valley,and hilltop) in each of two forests:logged and *** topographic features,altitude and degree of slope,were measured and related with species ***,there were significant effects of logging and topographic habitat and their interaction on species diversity and composition,with the unlogged forest and valley habitat supporting higher *** diversity varied among the topographic habitats in the logged but not in the unlogged *** were topographic effects on abundance of individual species but not on tree community abundance and basal *** and its interaction with topographic habitat showed significant effects on tree abundance and basal *** species were associated with specific topographic habitats or a combination in the logged and unlogged ***,the patterns of habitat associations of the species differed between the logged and unlogged forests.

关键词： Altitude Community structure Disturbance Habitat heterogeneity Slope Topographic position

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Concentration Heterogeneity in Structure of Intermetallic Synthesized under Compression

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Journal of Materials Science & Technology 2002年第5期18卷 432-435页

作者： O.b.Perevalova M.b.Fedorischeva V.e.Ovcharenko HuiheSU Inst Strength Phys & Mat Sci Tomsk 634055 Russia Chinese Acad Sci Inst Met Res Shenyang 110016 Peoples R China

by X-ray analysis, TeM and SeM methods the phase composition, microstructure, and deviation from stoichiometric composition were investigated for the Ni3Al intermetallic compound obtained by cast and self-propagation high-temperature synthesis under compression with followed homogenization anneal, with the Al concentration being 24.0 and 25.0 at. pct with and without b (0.5 at. pct). It was discovered that in SHS intermetallic alloys an average local deviation from stoichiometric composition is significantly more than in the cast alloy. Dependence of the local deviation from the stoichiometric composition on the distance has a zig zag nature at the level of the grain groups. Deviation from the stoichiometric composition at the boundaries of the general type is less than at the boundaries of the special type. When the intensity of boundary migrations of the general type decreases, the degree of deviation from the stoichiometric composition increases. There is correlation between the solubility of b in the crystalline lattice of the Ni3Al phase and the value of the deviation from the stoichiometric composition in the grains. When the b concentration in a solid solution increases, the deviation from stoichiometric composition decreases.

关键词： Ni3Al Intermetallic SHS Heterogeneity

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Structural and chemical mechanisms governing stability of inorganic Janus nanotubes

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npj Computational Materials 2021年第1期7卷 380-387页

作者： Felix T.bölle August e.G.Mikkelsen Kristian S.Thygesen Tejs Vegge Ivano e.Castelli Department of energy Conversion and Storage Technical University of DenmarkKgs.LyngbyDenmark Department of Physics Technical University of DenmarkKgs.LyngbyDenmark

One-dimensional inorganic nanotubes hold promise for technological applications due to their distinct physical/chemical properties,but so far advancements have been hampered by difficulties in producing single-wall nanotubes with a well-defined *** this work we investigate,based on Density Functional Theory(DFT),the formation mechanism of 135 different inorganic nanotubes formed by the intrinsic self-rolling driving force found in asymmetric 2D Janus *** show that for isovalent Janus sheets,the lattice mismatch between inner and outer atomic layers is the driving force behind the nanotube formation,while in the non-isovalent case it is governed by the difference in chemical bond strength of the inner and outer layer leading to steric *** our pool of candidate structures we have identified more than 100 tubes with a preferred radius below 35Å,which we hypothesize can display distinctive properties compared to their parent 2D *** descriptors have been identified to accelerate the discovery of small-radius tubes and a bayesian regression approach has been implemented to assess the uncertainty in our predictions on the radius.

关键词： inorganic chemical radius

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Frequency of *** pathotypes in acute diarrhea of children and its related factorsat beassat hospital,Sanandaj

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Asian Pacific Journal of Tropical Medicine 2009年第4期2卷 64-66页

作者： Kalantar e Solatni J Khosravi b Salehi A Kurdistan Digestive and Liver Research Center beasat Hospital Kurdistan University of Medical SciencesSanandajIran Department of Pediatric Beasat HospitalKurdistan University of Medical SciencesSanandajIran Department of Statistic Azad UniversitySanandajIran

Objective:Diarrhea is a leading cause of morbidity and mortality among children in developing *** bacterial pathogen most commonly associated with childhood diarrhea is escherichia coli.A one-year prospective study was carried out in Sanandaj to determine the prevalence and roles of the different *** pathotypes in children less than five years of age with acute ***:Rectal swab were collected prospectively from children with acute diarrhea and transported to the Department of Microbiology,School of Medicine, KUMS,Sanandaj during *** study was approved by the institutional ethics ***:During this study period,rectal swabs were investigated from a total of 466 children 1 to 144 months of age(mean, 29.97 months±S.D) with *** the children,191(41%,191/466) were girls,and 275 (59%,275/466) were *** age-specific incidence rates of acute diarrhea among children 13-24 and 1 - 12 months of age were 37.37%(37/99) and 26.26%(26/99),respectively,during the study period.A total of 99 strains of *** were *** 59(59.59%) and eIeC 22(22.22%),were the most commonly found escherichia coli strains detected in stools from *** diffusion testing showed *** strains resistance to tetracycline(89.89%),chloramphenicol(88.88%),Ampicillin(79.79%),Amoxicillin (75.75%) and Ceficime(75.75%).Among risk factors like age,sex,haemoglubin,fathers and mothers education,food and weight of children only mother's education was significant(P =0.018).Conclusion: In most of the clinical laboratories in Iran,*** does not considered as an etiologic agent responsible for diarrhea. Results in this study revealed that *** should be considered as an etiologic agent causing acute diarrhea among *** therefore,recommend the routine isolation and identification of *** strains in all the clinical laboratories in *** for appropriate use of antibiotics in Sanandaj need updating.

关键词： Prevalence of acute diarrhea Children e.coli strains Sanandaj

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Development of Zeff diagnostic system on the Globus-M（M2） tokamak and the first experimental results

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Plasma Science and Technology 2019年第10期21卷 33-39页

作者： e A TUKHMeNeVA S Yu TOLSTYAKOV G S KURSKIeV V K GUSeV V b MINAeV Yu V PeTROV N V SAKHAROV A Yu TeLNOVA N N bAKHAReV P b SHeGOLeV e O KISeLeV Ioffe Institute

Studying the behavior of effective ion charge Zeff, which indicates the degree of pollution of plasma and can provide valuable information about many processes taking place in plasma, mechanisms of the releasing impurities, transport, etc is of great interest. This paper describes the development of the Zeff diagnostic system for the Globus-M2 tokamak. The effective ion charge is determined on the basis of measurements of the bremsstrahlung intensity and Thomson scattering data-Te and ne profiles. The results of the first Zeff measurements obtained for several discharges on the Globus-M tokamak are presented in this paper. The results have been validated by simulation using the ASTRA transport code for the same discharges, and it has demonstrated a good agreement with the experimental results.

关键词： tokamak effective ion charge magnetic confinement

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