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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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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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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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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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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 s.ntino 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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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 s.ntino 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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Characterization of atmospheric aerosol (PM10 and PM2.5) from a medium sized city in s?o Paulo state,Brazil

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Journal of Environmental sciences 2020年第3期32卷 238-251页

作者： Bruno T.Franzin Filipe C.Guizellini Diego V.de Babos Ossamu Hojo Ieda Ap.Pastre Mary R.R.marchi Fernando L.Fertonani Cristina M.R.R.Oliveira sao Paulo state University(Unesp) Chemistry InstituteAnalytical Chemistry DepartmentAraraquaraSP14800-060Brazil Federal University of sao Carlos-UFsCAr Chemistry DepartmentSao CarlosSP13565-905Brazil Chemistry and Environmental sciences Department BiosciencesLanguages and Exact Sciences InstituteIbilceSaoPaulo State University(Unesp)Sao Jose do Rio PretoSP15054-000Brazil Centro de Quimica Estrutural-Faculdade de Ciencias da Universidade de Lisboa Edif.C8Campo Grande1749-016 LisboaPortugal

Air pollution causes deleterious effects on human health with aerosols being among the most polluting *** objective of this work is the characterization of the PM2.5 and PM10 aerosol mass in the *** methods of analysis include WD-XRF and *** were correlated with meteorological information and air mass trajectories(model HYsPLIT)by multivariate analysis.A morphological structural analysis was also carried out to identify the probable sources of atmospheric aerosols in the city of sao Jose do Rio Preto,*** mean mass concentration values obtained were 24.54 μg/m^3 for PM10,above the WHO annual standard value of 20 μg/m^3 and 10.88 μg/m^3 for PM2.5 whose WHO recommended limit is10 μg/m^***-XRF analysis of the samples revealed si and Al as major components of the coarse *** the fine fraction,the major elements were Al and *** sEM-FEG characterization allowed identifying the morphology of the particles in agglomerates,ellipsoids and filaments in the PM10,besides spherical in the *** analysis by EDs corroborated WD-XRF results,identifying the crustal elements,aluminosilicates and elements of anthropogenic origin in the coarse *** the fine fraction crustal elements were also identified;aluminosilicates,black carbon and spherical particles(C and O) originating from combustion processes were *** use of multivariate analysis to correlate air mass trajectories with the results of the morpho-structural characterization of the particulate matter allowed confirmation of the complex composition of the particles resulting from the combination of both local and long-distance sources.

关键词： Urban aerosol PM10 PM2.5 WD-XRF sEM-EDs

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Hemodynamic monitoring during liver transplantation:A state of the art review

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World Journal of Hepatology 2015年第10期7卷 1302-1311页

作者： Mona Rezai Rudnick Lorenzo De marchi Jeffrey s Plotkin Department of Anesthesiology Georgetown University Hospital

Orthotopic liver transplantation can be marked by significant hemodynamic instability requiring the use of a variety of hemodynamic monitors to aide in intraoperative management. Invasive blood pressure monitoring is essential,but the accuracy of peripheral readings in comparison to central measurements has been questioned. When discrepancies exist,central mean arterial pressure,usually measured at the femoral artery,is considered more indicative of adequateperfusion than those measured peripherally. The traditional pulmonary artery catheter is less frequently used due to its invasive nature and known limitations in measuring preload but still plays an important role in measuring cardiac output(CO) when required and in the management of portopulmonary hypertension. Pulse wave analysis is a newer technology that uses computer algorithms to calculate CO,stroke volume variation(sVV) and pulse pressure variation(PPV). Although sVV and PPV have been found to be accurate predicators of fluid responsiveness,CO measurements are not reliable during liver transplantation. Transesophageal echocardiography is finding an increasing role in the realtime monitoring of preload status,cardiac contractility and the diagnosis of a variety of pathologies. It is limited by the expertise required,limited transgastric views during key portions of the operation,the potential for esophageal varix rupture and difficulty in obtaining quantitative measures of CO in the absence of tricuspid regurgitation.

关键词： Intraoperative monitoring Physiologicmonitoring Liver transplantation

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Role of abdominal ultrasound for the surveillance follow-up of pancreatic cystic neoplasms: a cost-effective safe alternative to the routine use of magnetic resonance imaging

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World Journal of Gastroenterology 2019年第18期25卷 2217-2228页

作者： Luca Morelli simone Guadagni Valerio Borrelli Roberta Pisano Gregorio Di Franco Matteo Palmeri Niccolò Furbetta Dario Gambaccini s.ntino marchi Piero Boraschi Luca Bastiani Alessandro Campatelli Franco Mosca Giulio Di Candio General surgery Unit Department of Surgery Translational and New Technologies in Medicine University of Pisa EndoCAs (Center for Computer Assisted surgery) University of Pisa Diagnostic and Interventional Ultrasound in Transplants Unit Azienda Ospedaliero-Universitaria Pisana Gastroenterology Unit University of Pisa 2~(nd) Radiology Unit Department of Diagnostic Imaging Azienda Ospedaliero-Universitaria Pisana Institute of Clinical Physiology National Council of Research

BACKGROUND Patients with pancreatic cystic neoplasms(PCN), without surgical indication at the time of diagnosis according to current guidelines, require lifetime imagebased surveillance follow-up. In these patients, the current European evidencedbased guidelines advise magnetic resonance imaging(MRI) scanning every 6 mo in the first year, then annually for the next five years, without reference to any role for trans-abdominal ultrasound(Us). In this study, we report on our clinical experience of a follow-up strategy of image-based surveillance with Us, and restricted use of MRI every two years and for urgent evaluation whenever suspicious changes are detected by *** To report the results and cost-efficacy of a Us-based surveillance follow-up for known PCNs, with restricted use of *** We retrospectively evaluated the records of all the patients treated in our institution with non-surgical PCN who received follow-up abdominal Us and restricted MRI from the time of diagnosis, between January 2012 and January 2017. After Us diagnosis and MRI confirmation, all patients underwent Us surveillance every 6 mo for the first year, and then annually. A MRI scan was routinely performed every 2 years, or at any stage for all suspicious Us *** this communication, we reported the clinical results of this alternative followup, and the results of a comparative cost-analysis between our surveillance protocol(abdominal Us and restricted MRI) and the same patient cohort that has been followed-up in strict accordance with the European guidelines recommended for an exclusive MRI-based surveillance *** In the 5-year period, 200 patients entered the prescribed Us-restricted MRI surveillance follow-up. Mean follow-up period was 25.1 ± 18.2 mo. surgery was required in two patients(1%) because of the appearance of suspicious features at imaging(with complete concordance between the Us scan and the on-demand MRI). During the follow-up, Us revealed changes in PCN

关键词： Ultrasound Pancreatic cystic neoplasms Magnetic resonance imaging surveillance

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