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Experimental investigation and prediction of free fall jet scouring using machine learning models

International Journal of sediment Research 2023年第3期38卷 405-420页

作者： Farzin salmasi Parveen sihag john Abraham Meysam Nouri Department of Water Engineering Faculty of Agriculture University of Tabriz Department of Civil Engineering Chandigarh University school of Engineering University of St.Thomas Minnesota Department of Water Engineering Faculty of Agriculture Urmia University Department of Civil Engineering Saeb University

The current study deals with the depth of scour at the location of impact between a free fall jet and a riverbed. The current study is based on extensive laboratory experiments that were designed to mimic full-scale behavior. The literature review shows that relations among hydraulic parameters for predicting the depth of scour are complex; therefore, six artificial intelligence techniques are used in the current study to capture these complex relation. A total of 120 observations are used for the analysis. Results from the experiments show that with increasing downstream water depth(h), the impinging jet causes increasingly turbulent currents and large vortices that increase the scouring of the riverbed. Increasing discharge per unit width(q) enhances the relative scour depth(D/H) while increasing the average diameter of the riverbed materials(d) decreases D/H, where D is maximum scour depth and H is the height of the falling jet. With increasing(particle Froude number Fr), the relative scour depth *** the current study the prediction accuracy of Gene Expression Programming(GEP), Multivariate Adaptive Regression spline(MARs), M5P Tree, Random Forest(RF), Random Tree(RT), and Reduces Error Pruning Tree(REP Tree) techniques are evaluated using the relative scour depth(D/(H-h)). The performance evaluation indices and graphical methods suggest that the GEP based model is more accurate than other prediction methods for the relative scour depth with a coefficient of determination(R2) equal to 0.8330 and 0.8270, a mean absolute error(MAE) equal to 0.1125 and 0.0902, root mean square error(RMsE) values of 0.1463 and 0.1116, and Willmott’s Index(WI) equal to 0.8998 and 0.9014, for the training and testing stages.

关键词： Free jet scour Gene Expression Programming (GEP) Random Forest (RF) Multivariate Adaptive Regression spline (MARs)

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Holocene initiation and expansion of the southern margins of northern peatlands triggered by the East Asian summer monsoon recession

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Geoscience Frontiers 2023年第2期14卷 256-267页

作者： Mingming Zhang john P.smol Zhaojun Bu Key Laboratory of Geographical Processes and Ecological security in Changbai Mountains Ministry of EducationSchool of Geographical SciencesNortheast Normal UniversityChangchun 130024China state Environmental Protection Key Laboratory of Wetland Ecology and Vegetation Restoration Institute for Peat and Mire ResearchNortheast Normal UniversityChangchun 130024China Jilin Provincial Key Laboratory for Wetland Ecological Processes and Environmental Change in the Changbai Mountains Changchun 130024China Paleoecological Environmental Assessment and Research Laboratory Department of BiologyQueen’s UniversityKingstonON K7L 3N6Canada

Northern peatlands represent one of the largest biospheric carbon reservoirs in the *** southern margins act as new carbon reservoirs,which can greatly influence the global carbon ***,the Holocene initiation,expansion and climate sensitivity of these peatlands remain intensely *** we used a compilation of basal peat ages across six isolated peatlands at the southern margins of northern peatlands to address these *** found that the earliest initiation event of these peatlands occurred after the Younger Dryas(YD,12,800–11,700 years ago)*** second initiation event and rapid expansion occurred since 5 ka *** recession of East Asian summer monsoon(EAsM)during the YD period and at around 5 ka *** likely played a major role in controlling the initiation and expansion of these *** rapid expansion of these peatlands possibly contributed to the significant increases in atmospheric methane concentrations during the late Holocene because of the minerotrophic fens status and rapid expansion of *** ecological processes are different from northern peatlands,indicating the special carbon sink and source implications of these peatlands in the global carbon cycle.

关键词： Initiation and expansion Northern peatlands East Asian summer monsoon recession ENsO activities Atmospheric methane concentrations

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High-Energy Batteries:Beyond Lithium-Ion and Their Long Road to Commercialisation

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Nano-Micro Letters 2022年第6期14卷 116-164页

作者： Yulin Gao Zhenghui Pan Jianguo sun Zhaolin Liu john Wang Department of Materials science and Engineering National University of SingaporeSingapore 117574Singapore sT Engineering Advanced Material Engineering Pte.Ltd. Singapore 619523Singapore Institute of Materials Research and Engineering Agency for ScienceTechnology and Research(A*STAR)Singapore 138634Singapore school of Materials science and Engineering Tongji UniversityShanghai 201804China

Rechargeable batteries of high energy density and overall performance are becoming a critically important technology in the rapidly changing society of the twenty-first *** lithium-ion batteries have so far been the dominant choice,numerous emerging applications call for higher capacity,better safety and lower costs while maintaining sufficient *** design space for potentially better alternatives is extremely large,with numerous new chemistries and architectures being simultaneously *** include other insertion ions(*** and numerous multivalent ions),conversion electrode materials(***,metallic anodes,halides and chalcogens)and aqueous and solid ***,each of these potential“beyond lithium-ion”alternatives faces numerous challenges that often lead to very poor cyclability,especially at the commercial cell level,while lithium-ion batteries continue to improve in performance and decrease in *** review examines fundamental principles to rationalise these numerous developments,and in each case,a brief overview is given on the advantages,advances,remaining challenges preventing cell-level implementation and the state-of-the-art of the solutions to these ***,research and development results obtained in academia are compared to emerging commercial examples,as a commentary on the current and near-future viability of these“beyond lithium-ion”alternatives.

关键词： High energy density Beyond lithium-ion batteries Multivalent-ion batteries Conversion electrode materials Electrolyte

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Key challenges and approaches to addressing barriers in forest carbon offset projects

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Journal of Forestry Research 2022年第4期33卷 1109-1122页

作者： Chunyu Pan Anil shrestha john LInnes Guomo Zhou Nuyun Li Jinliang Li Yeyun He Chunguang sheng john-ONiles Guangyu Wang Faculty of Forestry University of British Columbia2424 Main MallVancouverBC V6T 1Z4Canada Zhejiang Prov Key Lab of Carbon Cycling Forest Ecosystem Zhejiang A&F UniversityLinan 311300People’s Republic of China China Green Carbon Foundation No.18Hepingli DongjieBeijing 100714People’s Republic of China College of Economics and Management Northeast Forestry UniversityHarbin 150040People’s Republic of China University of California San Diego9500 Gilman DriveLa JollaSan DiegoCA 92093USA

Forest carbon offset(FCO)projects play an increasingly important role in mitigating climate change through market mechanisms in both compliance and voluntary ***,there are challenges and barriers to developing an FCO project,such as carbon leakage and cost-eff *** have been few attempts to summarize and synthesize all types and aspects of existing challenges and possible solutions for FCO *** paper systematically reviews and discusses the current challenges involved in developing FCO projects,and then draws on the experience and lessons of existing projects to show how those challenges were addressed in world-leading voluntary carbon standards,namely the Verifi ed Carbon standard,the American Carbon Registry,the Climate Action Reserve,and Plan *** voluntary markets have rich experience in FCO projects and are responsible for a signifi cant share of the *** the 53 publications used in this analysis,three broad thematic categories of challenges *** were related to methodology,socio-economic implications,and *** challenges,particularly additionality,permanence,and leakage,were the focus of 46%of the selected research papers,while socio-economic challenges,including transaction,social,and opportunity costs,were addressed by 35%.The remaining 19%of the research articles focused on implementational challenges related to monitoring,reporting,and verifi *** voluntary standards adequately addressed most of the methodological and implementational barriers by adopting various ***,the standards did not adequately address socio-economic issues,despite these being the second most frequently discussed theme in the papers *** research is clearly needed on the socio-economic challenges involved in the development of FCO *** the development of high-quality forestry carbon off set projects,there are many challenges and no simple,universal recipe for addressi

关键词： Forest carbon Offset schemes Market mechanisms Challenges Opportunities

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Unraveling the Dynamic Role of Microtubules in the HBV Life Cycle

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Journal of Clinical and Translational Hepatology 2022年第3期10卷 383-385页

作者： Urania Georgopoulou john Koskinas Molecular Virology Laboratory Hellenic Pasteur InstituteAthensGreece Department of Internal Medicine Medical SchoolNational and Kapodistrian University of AthensHippokration HospitalAthensGreece

Acute hepatitis B virus(HBV)infection can progress to chronicity and development of cirrhosis and hepatocellular carcinoma(HCC).Current antiviral drugs offer long-term virological and biochemical response in patients with chronic HBV infection but they are unable to cure HBV.1,2 Many viruses,including HBV,exploit the host microenvironment for their efficient replication and *** the dynamic interactions between viruses and host cytoskeletal proteins vary,the microtubular network always provides a mode of directed transport for the invading *** viral entry,the microtubular network undergoes structural reorganization,indicating that invading pathogens not only utilize,but also alter the host cell cytoskeleton during replication and *** network is regulated by several post-translational modifications of tubulin along with microtubule(MT)-associated proteins(MAPs).3 It is well known that MAP1s links autophagic cytoplasmic components to MTs and mitochondria,affecting autophagosome biogenesis and ***,depletion of the MAP1s gene in mice causes deficiencies of both basal autophagy for subsequent clearance of abnormal mitochondria and nutritional stress-induced autophagy for cell longevity and nutrient *** defects that result from oxidative stress can subsequently either suppress tumorigenesis by triggering cell death or,support tumorigenesis if the cells survive the effects of oxidative stress.

关键词： utilize oxidative depletion

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Urban Plant Biomass Residues from the Neotropics and Their Potential for Thermal Energy Generation

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Journal of Renewable Materials 2023年第9期11卷 3547-3566页

作者： john Freddy Gelves Díaz Ludovic Dorkis Richard Monroy-sepúlveda sandra Rozo-Rincón Gabriel de Jesús Camargo Vargas Competitiveness and sustainability for Development Research Group Faculty of EngineeringUniversidad Libre-Cúcuta SectionalCúcutaColombia Catalysis and Nanomaterials Research Group Faculty of MinesUniversidad Nacional de Colombia-Medellín SectionalMedellínColombia Detecal Research Group Faculty of EngineeringUniversidad Libre-BogotáSectionalBogotáColombia

The material associated with tree pruning in a city in the Colombian neotropics was characterized in order to determine its energy *** species studied for their relevance in the territory were Prosopis juliflora,Licania tomentosa,Terminalia catappa,Azadirachta indica,Pithecellobium dulce,Ficus benjamina and Leucaena *** content,bulk density,hygroscopic response,elemental chemical analysis,proximal analysis,calorific value,ease of ignition and combustion,thermogravimetric and heat flow analysis,steam generation capacity,and qualitative analysis of gases(mass spectrometry)were *** results that were obtained show high initial moisture contents that vary between 37%and 67%and a variable density(when dry)between 0.21 and 0.41 g/***,it was shown that all residues have lower carbon and sulfur content compared to a reference mineral ***,the residues of some species have higher nitrogen contents compared to the same *** biomasses are characterized by their high content of volatile fractions and by having a lower content of inorganic matter compared to *** lower calorific values of these residues are between 14170 and 16928 kJ/kg,which are not negligible compared to other *** characteristic would be related to the high presence of hemicellulose in the *** gas monitoring revealed that there are different airflow needs in order to ensure complete *** generation tests showed that the calorific value should not be the most relevant criterion to establish the potential use of the waste,since leucaena leucocephala,despite having the highest calorific value,was the material with the lowest performance in steam generation.

关键词： Calorific value characterization combustion combustible material urban flora

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Free Cyclic Actions on surfaces and the Borsuk-Ulam Theorem

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Acta Mathematica sinica,English series 2022年第10期38卷 1803-1822页

作者： Daciberg Lima GONCALVEs john GUAsCHI Vinicius Casteluber LAAss Departamento de Matematica IMEUniversidade de Sao PauloRua do Matao 1010 CEP:05508-090Sao Paulo-SPBrazil Normandie Univ. UNICAENCNRSLMNO14000 CaenFrance Universidade Federal da Bahia IMEDepartamento de MatematicaAv.Milton SantosS/N Ondina CEP:40170-110Salvador-BABrazil

Let M and N be topological spaces,let G be a group,and letτ:G×M→M be a proper free action of *** this paper,we define a Borsuk-Ulam-type property for homotopy classes of maps from M to N with respect to the pair(G,τ)that generalises the classical antipodal Borsuk-Ulam theorem of maps from the n-sphere s^(n) to R^(n).In the cases where M is a finite pathwise-connected CWcomplex,G is a finite,non-trivial Abelian group,τis a proper free cellular action,and N is either R^(2) or a compact surface without boundary different from s^(2) and RP^(2),we give an algebraic criterion involving braid groups to decide whether a free homotopy class β∈[M,N]has the Borsuk-Ulam *** an application of this criterion,we consider the case where M is a compact surface without boundary equipped with a free actionτof the finite cyclic group *** terms of the orient ability of the orbit space Mof M by the actionτ,the value of n modulo 4 and a certain algebraic condition involving the first homology group of M,we are able to determine if the single homotopy class of maps from M to R^(2) possesses the Borsuk-Ulam property with respect to(Z_(n),τ).Finally,we give some examples of surfaces on which the symmetric group acts,and for these cases,we obtain some partial results regarding the Borsuk-Ulam property for maps whose target is R^(2).

关键词： Borsuk-Ulam theorem cyclic groups braid groups surfaces

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Femtosecond laser-assisted astigmatic keratotomy: a review

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Eye and Vision 2018年第1期5卷 59-69页

作者： john s.M.Chang Department of Ophthalmology Hong Kong Sanatorium&Hospital8/FLi Shu Pui BlockPhase II2 Village RoadHappy ValleyHong KongChina

Background:Astigmatic keratotomy(AK)remains an accessible means to correct surgically induced or naturally occurring *** advantages of femtosecond laser-assisted astigmatic keratotomy(FsAK)over conventional methods have been recognized *** text:This review evaluates the efficacy,complications,and different methods of FsAK for correction of astigmatism in native eyes and those that underwent previous penetrating keratoplasty(PKP).The penetrating and intrastromal FsAK(IFsAK)techniques can reduce post-keratoplasty astigmatism by 35.4%to 84.77%and 23.53%to 89.42%,*** native eyes,the penetrating and IFsAK techniques reduce astigmatism by 26.8%to 58.62%and 36.3%to 58%respectively,implying that the magnitude of the astigmatic reduction is comparable between the two FsAK ***,IFsAK offers the additional advantages of almost no risk of infection,wound gape,and epithelial *** use of nomograms,anterior-segment optical coherence tomography,and consideration of posterior cornea and corneal biomechanics are helpful to enhance the efficacy and safety of *** complications of FsAK in eyes that underwent PKP include overcorrection,visual loss,microperforations,infectious keratitis,allograft rejection,and *** reported difficulties in native eyes include overcorrection,anterior gas breakthrough,and suction ***:In eyes that underwent PKP,FsAK effectively reduces high regular or irregular astigmatism,with rare and manageable ***,the drawbacks of the procedure include the potential loss of visual acuity and low *** native eyes undergoing femtosecond laser-assisted cataract surgery,IFsAK is a good choice to correct low astigmatism(s).The refractive effect of astigmatism from the posterior cornea needs to be considered in the nomograms for native eyes undergoing refractive cataract *** further improve the efficacy of FsAK,more large-scale ra

关键词： Femtosecond laser-assisted astigmatic keratotomy Post-keratoplasty astigmatism Astigmatism correction Refractive surgery

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Can bedside needle arthroscopy of the ankle be an accurate option for intra-articular delivery of injectable agents?

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World Journal of Orthopedics 2022年第1期13卷 78-86页

作者： Tobias stornebrink sjoerd A s stufkens Nathaniel P Mercer john G Kennedy Gino M M J Kerkhoffs Department of Orthopedic surgery Amsterdam UMCUniversity of AmsterdamAmsterdam Movement SciencesAmsterdam 1105AZNetherlands Academic Center for Evidence based sports Medicine Amsterdam 1105AZNetherlands Amsterdam Collaboration for Health and safety in sports International Olympic Committee Research Center Amsterdam UMCAmsterdam 1105AZNetherlands Department of Orthopedic surgery NYU Langone HealthNew YorkNY 10010United States

BACKGROUND Bedside needle arthroscopy of the ankle under local anesthesia has been proposed for intra-articular delivery of injectable *** and tolerability of this approach in the clinical setting–including patients with end-stage ankle pathology and/or a history of prior surgery–is not *** To assess clinical accuracy and tolerability of bedside needle arthroscopy as a delivery system for injectable agents into the tibiotalar *** This was a prospective study that included adult patients who were scheduled for an injection with hyaluronic acid to the tibiotalar *** our center,these injections are used as a last resort prior to extensive *** primary outcome was injection accuracy,which was defined as injecting through the arthroscopic cannula with intra-articular positioning confirmed by a clear arthroscopic view of the joint *** outcome measures included a patientreported numeric rating scale(NRs,0-10)of pain during the procedure and willingness of patients to return for the same *** of ankle pain at rest and during walking was collected at baseline and at 2-wk *** were monitored from inclusion up to a 2-wk control *** We performed 24 ***(46%)participants were male,and mean age was 46.8±14.5 *** was the indication for injection in 20(83%)cases,of which 8(33%)patients suffered from osteoarthritis Kellgren-Lawrence grade IV,and 10(42%)patients from Kellgren-Lawrence grade *** osteochondral defect was the indication for injection in 4(17%)cases.A history of ankle surgery was present in 14(58%)participants and a history of multiple ankle surgeries in 11(46%)*** was possible to confirm accuracy in 21(88%)*** 3(12%)participants where needle arthroscopy did not reach a clear view of the joint space all suffered from Kellgren-Lawrence grade IV *** during the procedure was reported with a median of 1[i

关键词： Ankle arthroscopy Nanoscope Needle arthroscopy Injections Proof of concept Patient experience

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The“Tears of the Virgin”at Lakes Entrance,southeast Australia were made by the intertidal barnacle Chthamalus antennatus(Cirripedia:Thoracica)and cyanobacteria

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Integrative Zoology 2017年第3期12卷 228-236页

作者： john s.BUCKERIDGE William A.NEWMAN Earth&Oceanic systems Group RMIT UniversityMelbourneVictoriaAustralia scripps Institution of Oceanography La JollaCaliforniaUSA

Curious eroded depressions,most resembling an eye shedding an elongate tear,are found in gently sloping,intertidal,carbonate-rich arenite outcropping on the sea coast near Lakes Entrance,Victoria,southeast *** depressions,known locally as“Tears of the Virgin,”are evidently formed by multiple generations of a barnacle,Chthamalus antennatus Darwin,1854 in association with *** the round part of a depression offers the barnacle a modicum of protection from impacts during high tides,it is also partially inhabited by cyanobacteria,which extend into and tend to fill the elongate *** such,this appears to be the first case of mutualism between a higher invertebrate and cyanobacteria,with the cyanobacteria reducing the barnacle’s risk of desiccation while receiving metabolic wastes from it during low *** is also the first record of a balanomorph barnacle eroding calcareous arenite beneath its shell,the net effect of which would be expected to reduce its adhesion to the ***,the siliceous residue,resulting from the barnacle’s dissolution of the more than 80%of the calcite-rich sedimentary rock,is sequestered in delicate folds on the inside of the shell wall as it grows.A brief review of cirripedes capable of excavation includes the first photographic documentation of excavation of a mollusc shell by a verrucomorph.

关键词： burrowing barnacles Chthamalus antennatus Cirripedia cyanobacteria mutualism

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