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Metrics for macroscale invasion and dispersal patterns

Journal of Plant Ecology 2018年第1期11卷 64-72页

作者： Teresa L.Clark basil v.iannoneⅲ Songlin Fei Department of Forestry and Natural Resources Purdue University715 W.State StreetWest LafayetteIN 47907USA School of Forest Resources and Conservation University of Florida1745 McCarty DriveGainesvilleFL 32611USA

Aim The ability to quantitatively measure the continuum of macroscale patterns of species invasion is a first step toward deeper understand-ing of their causal *** took advantage of two centuries worth of herbarium data,to evaluate a set of metrics to measure macroscale patterns,allowing cross-species comparisons of inva-sive expansion across large geographic *** We used herbarium specimens to reconstruct county-level invasion histories for two non-native plants(Alliaria petiolata and Lonicera japonica),with distinct spatiotemporal distribution patterns over the past two *** county centroids from species’ini-tial occurrences,we quantified point pattern metrics from multiple disciplines(*** crime analysis,landscape ecology etc.)that are historically used at smaller spatial scales,to evaluate their abil-ity to detect macroscale spatial diffusion and amount of directional *** were further assessed for their ease of use,data requirements,independence from other metrics and intuitiveness of *** Findings We identified four suitable metrics for distinguishing differences in spatial patterns:(i)standard distance,(ii)number of patches,(iii)Euclidean nearest neighbor summary class statistic coefficient of variation and(iv)mean center that when applied to county-level presence data allowed us to determine the directions by which distributions expanded and if distributions increased via outward expansion,infilling and/or jump dispersal *** metrics when compared during the same invasion phase are capable of quantifying macroscale variability among species in their distri-butional and dispersal *** able to quantify differences among species in these patterns is important in understanding the drivers of species dispersal *** metrics therefore repre-sent a simple yet thorough toolset for achieving this goal.

关键词： Alliaria petiolata diffusion herbarium jump dispersal Lonicera japonica plant invasions

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Tribology of Ti6Al4v: A review

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Friction 2019年第6期7卷 497-536页

作者： Jibin T PHILIP Jose MATHEW basil KURIACHEN Department of Mechanical Engineering National Institute of Technology MizoramAizawl 796012India Department of Mechanical Engineering National Institute of Technology CalicutCalicut 673601India

The deleterious innate attribute of Ti6 Al4 v, the workhorse material among the alloy series of titanium is its incompetent tribo-behavior. Infinite surface modification techniques, viz., the accretion of adherent appendage layers, diffusion hardening, infusion of residual stresses, microstructural evolution, and phase transformations were attempted to enhance the wear resistance of the alloy. The need lies to establish a bridge between the indigenous material properties and the tribo-characteristics of Ti6 Al4 v so that the enforced improvement techniques can raise the barriers of its applicability. A critical review of the microstructural transitions, mechanisms governing tribo-behavior and the parametric conditions leading to material removal at dry sliding conditions of Ti6 Al4 v, falls under the scope of this manuscript. Hence, the prime focus of the approach is to impart a clear-cut perception of the minute variations in mechanical, metallurgical, and tribological characteristics of the alloy at interactive instances with distinct counter-body surfaces.

关键词： Ti6Al4v tribology sliding behavior microstructure

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Electrocatalytic generation of hydrogen peroxide on cobalt nanoparticles embedded in nitrogen-doped carbon

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Chinese Journal of Catalysis 2021年第12期42卷 2296-2305页

作者： basil Sabri Rawah Wenzhen Li Chemical and Biological Engineering Department Biorenewables Research LaboratoryIowa State UniversityAmesIA 50011USA Chemical and Biological Engineering Department University of JeddahJeddah 23890Saudi Arabia

Electrocatalytic reduction of oxygen is a growing synthetic technique for the sustainable production of hydrogen peroxide(H_(2)O_(2)).The current challenges concern seeking low-cost,highly active,and selective ***-nitrogen-doped carbon containing catalytically active cobalt-nitrogen(Co-N_(x))sites is an emerging class of materials that can promote the electrochemical generation of H_(2)O_(2).Here,we report a straightforward method for the preparation of cobalt-nitrogen-doped carbon composed of a number of Co-N_(x)moieties using low-energy dry-state ball milling,followed by controlled *** scalable method uses inexpensive materials containing cobalt acetate,2-methylimidazole,and Ketjenblack EC-600JD as the metal,nitrogen,and carbon precursors,*** measurements in an acidic medium show the present material exhibits a significant increase in the oxygen reduction reaction current density,accompanied by shifting the onset potential into the positive *** current catalyst has also demonstrated an approximate 90%selectivity towards H_(2)O_(2)across a wide range of *** H_(2)O_(2)production rate,as measured by H_(2)O_(2)bulk electrolysis,has reached 100 mmol g_(cat).^(–1)h^(–1)with high H_(2)O_(2)faradaic efficiency close to 85%(for 2 h at 0.3 v ***).Lastly,the catalyst durability has been tested(for 6 h at 0.3 v ***).The catalyst has shown relatively consistent performance,while the overall faradic efficiency reaches approximate 85%throughout the test cycle indicating the promising catalyst durability for practical *** formed Co-N_(x)moieties,along with other parameters,including the acidic environment and the applied potential,likely are the primary reasons for such high activity and selectivity to H_(2)O_(2)production.

关键词： Hydrogen peroxide Two-electron oxygen reduction Carbon catalyst Electrocatalysis

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The Mamfe Basin in the southern Benue trough extension between Cameroon and Nigeria:Gem origin and problem of lithostratigraphic nomenclature and marine transgression

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Acta Geochimica 2023年第3期42卷 495-516页

作者： Milan Stafford Tchouatcha Primus Tamfuh Azinwi Christel Sobdjou Kemteu Augustin Desire Balla Ondoa Leopold Darlus Ngantchu basil Azeh Anong Courage Gabvourta Department of Earth Sciences Faculty of ScienceUniversity of DschangP.O.Box 67DschangCameroon Department of Soil Science Faculty of Agronomy and Agricultural SciencesUniversity of DschangP.O.Box 222DschangCameroon Department of Mining and Mineral Engineering National Higher Polytechnic InstituteUniversity of BamendaP.O.Box 39BambiliCameroon Department of Earth Sciences Faculty of ScienceUniversity of YaoundeIP.O.Box 812Yaounde´Cameroon Department of Earth Sciences Faculty of ScienceUniversity of NgaoundereP.O.Box 454NgaoundereCameroun

The Mamfe Basin has been the subject of many studies,but some debates persist,especially concerning the stratigraphic nomenclature,corundum origin,and marine *** aims of this work are(1)to propose a new lithostratigraphic nomenclature of the Mamfe Basin formation based on new field observations,(2)to determine the source rock distribution and the origin of gem deposits and(3)to correlate the Cameroon section of the Mamfe Basin with the Nigerian *** main results show that the name Manyu River Group is more appropriate as the Manyu River crosses all the facies in the Mamfe sedimentary Basin belonging to the Manyu *** to the facies analysis,the age of deposition,the mineralogic and geochemical data such as the v ***2O3andΣREE ***_(2)O_(3),TiO_(2)MgO,Na_(2)O,P_(2)O_(5),and CaO diagrams,this Group is composed of at least five Formations,including four Cretaceous Formations,from bottom to top:the Etoko Formation(alluvial and fluvial channel to fluvio-lacustrine deposits),the Nfaitok Formation(lagoonal deposits),the Bachuo Ntai Formation(fluvial braided channels or fluvio-deltaic environment)and the Eyumojock/NsanaragatiFormation(fluvio-lacustrine deposits)and the new Cenozoic Formation named Bakebe Formation(fluvio-lacustrine deposits).The gem minerals such as corundum,rutile,or tourmaline in the Cretaceous deposits of the Mamfe Basin are mainly detrital as indicated by the presence of worn shapes and fragments of these *** presence of sapphire in the AlboCenomanian deposits indicates a Precambrian age of the felsic source rock,likely the plutonic rocks such as granite or pegmatite as indicated by the abundance of tourmaline and high LREE/HREE ratios(14.81–34.29)and slightly negative and positive Eu anomalies(0.85–1.15).This marine incursion in the Mamfe Basin was probably from West Nigeria,according to the geographic location of the Mamfe Basin and the general palaeogeographic evolution of the Benue Trough.

关键词： Lithostratigraphy Marine transgression Heavy minerals Sapphires Mamfe Basin Benue Trough

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Comparative Study of Fast Superposition, Superposition Algorithm in Intensity Modulated Radiotherapy Techniques for Prostate Cancer

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International Journal of Medical Physics, Clinical Engineering and Radiation Oncology 2020年第2期9卷 62-72页

作者： Mukesh Zope Deepali Patil Angel Kuriakose P. A. Aslam basil George Abhijeet Mandal Department of Medical Physics State Cancer Institute Indira Gandhi Institute of Medical Sciences Patna India Department of Radiotherapy Mahavir Cancer Sansthan Patna India Speciality of Medical Physics Super Speciality of Cancer Institute and Hospital Lucknow India Department of Radiotherapy Regional Cancer Care Center and Cancer Hospital Siddhpur India Department of Radiotheraphy & Radiation Medicine Institute of Medical Sciences Varansi India

This study aims to compare the dosimetric coverage of the Planning Target volume (PTv) and the dose to main organs at risk (OARs) between two different algorithms fast superposition (FSUP), superposition (SUP) using intensity-modulated radiotherapy (IMRT) techniques for prostate cancer. Ten patients with prostate cancer were selected for this study. For each patient, IMRT plans were created with 6 Mv photon beam quality using CMS XiO treatment planning system. The delivery of IMRT was carried out using the step and shoot techniques. The dose coverage for each patient was designated to an ICRU report 62 reference point in the PTv, medium coverage of the planned target volume to be 95% of the prescribed dose while the maximum dose in the target volume to be not greater than 107% of the prescribed dose. A hypofractionated prescription dose of 70 Gy/28# at 2.5 Gy per fraction was used. Besides we compared the number of MUs and OARs dose to D15%, D25%, D35%, D50% on both algorithm planning sets. For target, this evaluation was made with comparing the conformity index (CI) and homogeneity index (HI). In our study, the results show the OARs got less dose from the SUP algorithm compared to FSUP algorithms. Statistically not significant difference was observed in v107% of PTv, MU/CC, conformity Index (p = 0.057, p = 0.215, p = 0.370) and 95% PTv volume received prescription dose from both Plans. But Homogeneity Index for both algorithms was statistically significant (p = 0.000, p = 0.001). For prostate cancer, the superposition algorithm showed better results in the IMRT plan compared to the fast superposition algorithm.

关键词： Prostate Cancer IMRT Algorithm MUs Conformity Index Homogeneity Index

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β-苯甲基2∶3-内醚-D-同侧醣配醣物及其与苯甲醇钠的反应

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化学学报 1953年第3期 121-128页

作者：张滂李思固北京大学化学系英国剑桥大学

β-苯甲基2:3-内醚-4:6-苯亚甲基-D-同侧醣配醣物(Iv)由β-苯甲基D-葡萄糖配醣物經三步反应制得.它和苯甲醇钠的反应,与相应的α-甲基2:3-内醚-4:6-苯亚甲基-D-同侧醣配醣物相同,但析得的产物只有β-苯甲基2-苯甲基-4:6-苯亚甲基-D-2-... 详细信息

β-苯甲基2:3-内醚-4:6-苯亚甲基-D-同侧醣配醣物(Iv)由β-苯甲基D-葡萄糖配醣物經三步反应制得.它和苯甲醇钠的反应,与相应的α-甲基2:3-内醚-4:6-苯亚甲基-D-同侧醣配醣物相同,但析得的产物只有β-苯甲基2-苯甲基-4:6-苯亚甲基-D-2-异侧醣配醣物(v).以上的转化证明了配醣基的不同和构型的改变,至少在所研究的一个配醣物的结果来看,对于内醚环形成的构型是没有影响的.

关键词：苯甲基苯亚甲基葡萄糖苯甲醇苄基右旋糖己糖苄醇局部麻醉药同侧旋光度反应

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Identifying the occurrence time of an impending mainshock:a very recent case

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Earthquake Science 2015年第3期28卷 215-222页

作者： Panayiotis A.varotsos Nicholas v.Sarlis Efthimios S.Skordas Stavros-Richard G.Christopoulos Mary S.Lazaridou-varotsos Department of Solid State Physics and Solid Earth Physics Institute Faculty of Physics School of Science National and Kapodistrian University of Athens

The procedure by means of which the occurrence time of an impending mainshock can be identified by analyzing in natural time the seismicity in the candidate area subsequent to the recording of a precursory seismic electric signals（SES） activity is reviewed. Here, we report the application of this procedure to an MW5.4 mainshock that occurred in Greece on 17 November 2014. This mainshock（which is pretty rare since it is the strongest in that area for more than half a century） was preceded by an SES activity recorded on 27 July 2014, and the results of the natural time analysis reveal that the system approached the critical point（mainshock occurrence） early in the morning on 15 November 2014.

关键词： Seismic electric signals Natural time analysis Earthquake prediction Critical phenomena

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Genotoxicity of Some Essential Oils Frequently Used in Aromatherapy

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Advances in Bioscience and Biotechnology 2016年第2期7卷 63-73页

作者： Nadya Mezzoug Mohamed Idaomar Dominique Baudoux Pascal Debauche véronique Liemans Abdesselam Zhiri Laboratory of Biology and Health Faculté des Sciences Université Abdelmalek Essa&acircdi Tétouan Morocco S.A. PRANAROM International Ghislenghien Belgium

Genotoxic properties of the essential oils extracted from Artemisia dracunculus (tarragon), Ocimum basilicum (basil), Cinnamomum loureirii (cinnamon), Laurus nobilis (laurel), Satureja montana (savory) and Rosmarinus officinallis (rosemary) are studied by Drosophila melanogaster Somatic Mutation and Recombination Test (SMART). The high bioactivation crossed with a high cytochrome P450-dependent bioactivation capacity is used. This assay is principally based on the loss of heterozygosity of the suitable recessive markers’ multiple wing hairs (mwh) and flare-3 (flr3) which can lead to the formation of mutant clones of larval cells, and which are then going to be expressed as spots on the wings of adult flies. Third-instar larvae are treated for 48 hr with different concentrations of the essential oils dissolved in Tween-80 at 0.2% or 2%. The wings of the emerging adults are analyzed for the occurrence of different types of mutant spots. No statistically significant differences in spot frequencies between negative controls and treated series are observed. These results suggest that the six essential oils at concentrations tested are not genotoxic towards somatic cells of D. melanogaster.

关键词： Essential Oils Genotoxicity Somatic Mutation Mitotic Recombination Drosophila melanogaster

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