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Use of the Nitrogen Index to assess nitrate leaching and water drainage from plastic-mulched horticultural cropping systems of Florida

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International Soil and Water Conservation Research 2016年第4期4卷 237-244页

作者： Edilene C.S.marchi Lincoln Zotarelli Jorge A.Delgado Diane L.Rowland giuliano marchi Instituto Federal de Educacao Ciencia e Tecnologia de BrasiliaCampus PlanaltinaDFRodovia DF-128-21-Zona Rural de PlanaltinaBrasilia-DF 73380-900Brazil University of Florida-Horticultural Science Department 1241 Fifield HallGainesvilleFL 32611USA USDA-ARS Soil Management and Sugar Beet Research Unit2150 Centre Ave.Building DSuite 100Fort CollinsCO 80526USA Agronomy Department University of FloridaGainesvilleFLUSA Embrapa Cerrados Rod.BR 020km 18CP 08223CEP73310-970 Planaltina DFBrazil

Water quality in Florida is significantly impacted by nitrate(NO_(3)-N)leaching losses from agriculture in a large part of the *** crops are planted across large areas of Florida on coarse sandy soils with low soil water retention and soil organic matter,increasing the potential for NO_(3)-N *** leaching losses from the root zone of vegetable cropping systems can negatively impact *** tools such as the Nitrogen Index(N-Index)are able to quickly assess N use efficiency and losses via NO_(3)-N leaching from agricultural ***,the N-Index provides technical information about N losses pathways tied to agricultural management practices with a great level of confidence;this information has been used by researchers,growers and policymakers as a decision support ***,the current version of the NIndex that has been used for different field crops has not been calibrated to be used in plastic-mulched horticultural cropping *** aim of this work was to calibrate and validate the N-Index for plasticmulched horticultural cropping systems of *** study found that the N-Index tool accurately identified and ranked the risk of N losses in the evaluated horticultural *** N-Index was calibrated for Florida's plastic-mulched horticultural cropping systems using a sensitivity *** adjusted N-Index was validated using compiled data of vegetables grown under plastic mulching systems during three consecutive *** from these studies suggest that the N-Index can be an easy-to-use tool capable of assessing nitrogen management practices for vegetable *** tool can be used to guide nutrient managers in the implementation of best nitrogen management practices that could contribute to reduced NO_(3)-N leaching losses from vegetable systems in Florida,contributing to a smaller environmental footprint and conservation of water quality.

关键词： Florida,nitrogen management Nitrate leaching Water leaching,vegetables,plastic mulch

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Nonlinear versus linearised model on stand density model fitting and stand density index calculation: analysis of coefficients estimation via simulation

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Journal of Forestry Research 2019年第5期30卷 1595-1602页

作者： Maurizio marchi CREA-Research Centre for Forestry and Wood geoLAB-Laboratory of Forest Geomatics Department of Agriculture Food Environment and Forestry Università degli Studi di Firenze

The stand density index,one of the most important metrics for managing site occupancy,is generally calculated from empirical data by means of a coefficient derived from the“self-thinning rule”or stand density model.I undertook an exploratory analysis of model fitting based on simulated data.I discuss the use of the logarithmic transformation(i.e.,linearisation)of the relationship between the total number of trees per hectare(N)and the quadratic mean diameter of the stand(QMD).I compare the classic method used by Reineke(J Agric Res 46:627–638,1933),i.e.,linear OLS model fitting after logarithmic transformation of data,with the“pure”powerlaw model,which represents the native mathematical structure of this relationship.I evaluated the results according to the correlation between N and *** OLS and nonlinear fitting agreed in the estimation of coefficients only for highly correlated(between-1 and-0.85)or poorly correlated([-0.39)*** average correlation values(i.e.,between-0.75 and-0.4),it is probable that for practical applications,the differences were relevant,especially concerning the key coefficient for Reineke’s stand density index *** introduced a non-negligible bias in SDI *** linearised log–log model always estimated a lower slope term than did the exponent of the nonlinear function except at the extremes of the correlation *** the logarithmic transformation is mathematically correct and always equivalent to a nonlinear model in case of prediction of the dependent variable,the difference detected in my studies between the two methods(i.e.,coefficient estimation)was directly related to the correlation between N and QMD in each simulated/disturbed *** general,given the power law as the“natural”structure of the N versus QMD relationship,the nonlinear model is preferred,with a logarithmic transformation used only in the case of violation of parametric assumptions(*** distributed non-normally).

关键词： Ordinary least squares Power law Reineke function Silviculture Ecological mathematics Forest mathematics

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Past,present and future of industrial plantation forestry and implication on future timber harvesting technology

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Journal of Forestry Research 2020年第2期31卷 339-351页

作者： Andrew McEwan Enrico marchi Raffaele Spinelli Michal Brink Department of Agriculture Food and Forest SystemsFlorence UniversityVia San Bonaventura1350145 FlorenceItaly School of Natural Resource Management Nelson Mandela Metropolitan UniversityGeorge CampusGeorgeSouth Africa Consiglio Nazionale delle Ricerche Istituto per la BioEconomiaVia Madonna del Piano 10Sesto FiorentinoItaly Australian Forest Operations Research Alliance University of the Sunshine CoastLocked Bag 4Maroochydore DCQLD 4558Australia University of Pretoria Private Bag X20HatfieldPretoria 0028South Africa

Plantation forests are established,and expanding,to satisfy increasing global demand for timber *** societal values,such as safety,productivity,environmental,quality and social are influencing the plantation forestry *** is primarily driven through an ever increasing world population,which in turn influences the way nations view the value systems by which they *** people require more resources-also forest ***,the availability of information is influencing the pace of technological *** changes could result in a difference in the management of plantations that could affect the forest engineering systems of the *** review aimed to summarize the current status of plantation forests;summarize future developments and possible scenarios in forest plantation management for the various products;and assess whether these developments in a plantation environment could affect the harvesting systems *** influencing the form of plantations include the type and nature of the plantation owner;the change in demand for different and new forest products;climate change factors,including the use of biomass for energy,carbon sequestration and trading;ecosystem services and other products and services;and sustainability certification of forest *** impact and influence of these factors were summarised into a series of key drivers that will influence the technology used in harvesting machines,as well as the choice of harvesting machines,systems and *** drivers were the effect of variations in tree size,the expansion of plantation areas onto more difficult terrain,diversity in plantation design,increased attention towards site impacts and the increased use of biomass for *** information is provided regarding how the harvesting systems could be affected.

关键词： Plantations Forest products Biomass Harvesting system Mechanization Trends Technology

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Douglas-fir climate sensitivity at two contrasting sites along the southern limit of the European planting range

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Journal of Forestry Research 2020年第6期31卷 2193-2204页

作者： Cristiano Castaldi Maurizio marchi Giorgio Vacchiano Piermaria Corona CREA-Research Centre for Forestry and Wood Viale S.Margherita 8052100 ArezzoItaly Universitàdegli Studi di Milano DISAAVia Celoria 220133 MilanItaly

Douglas-fir(Pseudotsuga menziesii(Mirb.)Franco)is an important exotic tree species that was planted across a large part of Europe during the last *** both experimental trials and conventional forest plantations,the trees grow at a high rate and produce high-quality *** present study investigated climate-growth relationships of Douglas-fi r at two Italian sites that contrast in climate:a Mediterranean area in southern Italy(Mercurella site)and a cooler,moister site in the northern Apennines without summer aridity(Acquerino).The relationship between tree-ring chronologies and monthly climatic variables was evaluated by a moving average and correlation *** showed that the minimum temperature in February and in March play a key role for Douglas-fi r at both sites,with a positive eff ect on *** the northern site,it is also highly sensitive to late summer temperatures(negative correlation)and spring–summer precipitation(positive correlation).Growth rates in southern latitudes were high even in Europe and in the Mediterranean environment,with low sensitivity to climatic fl *** the basis of our results,further common garden experiments should test adaptation and the interaction between genetics and environment of second-or third-generation seeds from old stands across Europe such as done by the old International Union of Forest Research Organizations(IUFRO)or the European Douglasfi r Improvement Research Cooperative(EUDIREC)experimentation programmes.

关键词： Pseudotsuga menziesii Tree ring analysis Dendroclimatology Forest plantations Exotic forest species

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The peripheral T-cell lymphoma:can we pivot from the chemotherapy-predicated paradigm?

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Journal of Cancer Metastasis and Treatment 2022年第1期8卷 345-364页

作者： Helen Ma Enrica marchi Section of Hematology/Oncology VA Long Beach Healthcare SystemLong BeachCA 90822USA Division of Hematology/Oncology University of CaliforniaIrvineOrangeCA 92868USA Division of Hematology/Oncology University of VirginiaCharlottesvilleVA 22903USA

Peripheral T-cell lymphomas(PTCL)are uncommon and aggressive diseases that are difficult to *** chemotherapy such as cyclophosphamide,doxorubicin,vincristine,and prednisone has been the mainstay of treatment for almost 30 years,but outcomes remain *** development of new targeted therapies is changing the landscape of how we treat patients with these difficult *** instance,the addition of brentuximab vedotin to combination chemotherapy enhanced the outcomes in patients with CD30-positive anaplastic large cell lymphomas,but there is still a need for better therapies in the other numerous *** we discuss the data for the existing treatment paradigm of PTCL as well as the merits of shifting toward a chemotherapy-free approach.

关键词： Peripheral T-cell lymphomas PTCL chemotherapy-free epigenetics targeted therapy

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GIS tools for preliminary debris-flow assessment at regional scale

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Journal of Mountain Science 2017年第12期14卷 2498-2510页

作者： cavalli marco crema stefano trevisani sebastiano marchi lorenzo consiglio nazionale delle ricerche istituto di ricerca per la protezione idrogeologicaCorso Stati Uniti 435127 PadovaItaly universitàdi padova dipartimento territorio e sistemi agro-forestaliVia dell’Universita 1635020 Legnaro(PD)Italy universitàiuav di venezia dipartimento di architettura costruzione conservazioneDorsoduro 220630123 VeneziaItaly

The assessment of the areas endangered by debris flows is a major issue in the context of mountain watershed management. Depending on the scale of analysis, different methods are required for the assessment of the areas exposed to debris *** 2-D numerical models are advised for detailed mapping of inundation areas on individual alluvial fans, preliminary recognition of hazard areas at the regional scale can be adequately performed by less data-demanding methods, which enable priority ranking of channels and alluvial fans at risk by debris flows. This contribution focuses on a simple and fast procedure that has been implemented for regionalscale identification of debris-flow prone channels and prioritization of the related alluvial fans. The methodology is based on the analysis of morphometric parameters derived from Digital Elevation Models(DEMs). Potential initiation sites of debris flows are identified as the DEM cells that exceed a threshold of slope-dependent contributing area. Channel reaches corresponding to debris flows propagation, deceleration and stopping conditions are derived from thresholds of local slope. An analysis of longitudinal profiles is used for the computation of the runout distance of debris flows. Information on erosion-resistant bedrock channels and sediment availability surveyed in the field are taken into account in the applications. A set of software tools was developed and made available(https://***/Hydrogeomorphology Tools) to facilitate the application of the procedure. This approach, which has been extensively validated by means of field checks, has been extensively applied in the eastern Italian Alps. This contribution discusses potential and limitations of the method in the frame of the management of small mountain watersheds.

关键词： Debris flow Geographic information system Digital elevation models Runout Alluvial fan Watershed management Geomorphometry

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Differential diagnosis between functional and organic intestinal disorders:Is there a role for non-invasive tests?

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World Journal of Gastroenterology 2007年第2期13卷 219-223页

作者： Francesco Costa Maria Gloria Mumolo Santino marchi Massimo Bellini Section of Gastroenterology Department of Internal MedicineUniversity of Pisa Pisa Italy

Abdominal pain and bowel habits alterations are common symptoms in the general population. The investigation to differentiate organic from functional bowel disorders represents a considerable burden both for patients and public health service. The selection of patients who should undergo endoscopic and/or radiological procedures is one of the key points of the diagnostic process, which should avoid the abuse of invasive and expensive tests as well as the underestimation of potentially harmful diseases. Over the cominci years,dinidans and researchers will be challenged to develop strategies to increase the patient＇s compliance and to reduce the economic and social costs of the intestinal diseases.

关键词： Intestinal diseases Intestinal inflammation Functional bowel disorders Faecal markers

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Weakly Admissible Meshes and Discrete Extremal Sets

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Numerical Mathematics(Theory,Methods and Applications) 2011年第1期4卷 1-12页

作者： Len Bos Stefano De marchi Alvise Sommariva Marco Vianello Department of Computer Science University of VeronaStrada Le Grazie 15-37134 VeronaItaly Department of Pure and Applied Mathematics University of PaduaVia Trieste 63-35121 PaduaItaly

We present a brief survey on (Weakly) Admissible Meshes and corresponding Discrete Extremal Sets, namely Approximate Fekete Points and Discrete Leja *** provide new computational tools for polynomial least squares and interpolationon multidimensional compact sets, with different applications such as numerical cubature, digital filtering, spectral and high-order methods for PDEs.

关键词： Weakly admissible meshes Approximate Fekete points Discrete Leja points

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REFERENCE FUNCTIONAL AND CHARACTERISTIC SPACE FOR LAGRANGE AND BERNSTEIN OPERATORS

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Analysis in Theory and Applications 1995年第4期11卷 6-14页

作者： S.De marchi M.Morandi Cecchi Dept. of Pure and Applied Math. Via Belzoni 7-Padova ItalyDept. of Pure and Applied Math. Via Belzoni 7-Padova Italy

This paper deals with the description and the representation of polynomials defined over n-simplices, The polynomials are computed by using two recurrent schemes: the Neville-Aitken one for the Lagrange interpolating operator and the De Casteljau one for the Bernstein-Bezier approximating operator. Both schemes fall intothe framework of transformations of the form where the F iare given numbers (forexample, at the initial step they coincide with the values of the function on a given lattice), and the coefficients (x) are linear polynomials valued in x and x is fixed. A general theory for such sequence of transformations can be found in [2] where it is also proved that these tranformations are completely characterized in term of a linear functional, reference functional. This functional is associated with a linear space., characteristic *** concepts of reference functionals and characteristic spaces will be used and we shall prove the existence of a characteristic space for the reference functional: associated with these operators.

关键词： REFERENCE FUNCTIONAL AND CHARACTERISTIC SPACE FOR LAGRANGE AND BERNSTEIN OPERATORS

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Irritable bowel syndrome: a disease still searching for pathogenesis, diagnosis and therapy

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World Journal of Gastroenterology 2014年第27期20卷 8807-8820页

作者： Massimo Bellini Dario Gambaccini Cristina Stasi Maria Teresa Urbano Santino marchi Paolo Usai-Satta Gastrointestinal Unit Department of Gastroenterology University of Pisa 56124 Pisa Italy Department of Experimental and Clinical Medicine University of Florence 50134 Florence Italy Epidemiological Observatory Health Agency of Tuscany 50141 Florence Italy Gastrointestinal Unit P. Brotzu Hospital09124 Cagliari Italy

Irritable bowel syndrome (IBS) is the most frequently diagnosed functional gastrointestinal disorder in primary and secondary care. It is characterised by abdominal discomfort, pain and changes in bowel habits that can have a serious impact on the patient’s quality of life. The pathophysiology of IBS is not yet completely clear. Genetic, immune, environmental, inflammatory, neurological and psychological factors, in addition to visceral hypersensitivity, can all play an important role, one that most likely involves the complex interactions between the gut and the brain (gut-brain axis). The diagnosis of IBS can only be made on the basis of the symptoms of the Rome III criteria. Because the probability of organic disease in patients fulfilling the IBS criteria is very low, a careful medical history is critical and should pay particular attention to the possible comorbidities. Nevertheless, the severity of the patient’s symptoms or concerns sometimes compels the physician to perform useless and/or expensive diagnostic tests, transforming IBS into a diagnosis of exclusion. The presence of alarming symptoms (fever, weight loss, rectal bleeding, significant changes in blood chemistry), the presence of palpable abdominal masses, any recent onset of symptoms in patient aged over 50 years, the presence of symptoms at night, and a familial history of celiac disease, colorectal cancer and/or inflammatory bowel diseases all warrant investigation. Treatment strategies are based on the nature and severity of the symptoms, the degree of functional impairment of the bowel habits, and the presence of psychosocial disorders. This review examines and discusses the pathophysiological aspects and the diagnostic and therapeutic approaches available for patients with symptoms possibly related to IBS, pointing out controversial issues and the strengths and weaknesses of the current knowledge.

关键词： Irritable bowel syndrome Pathogenesis Diagnosis Therapy

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