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Live above-and belowground biomass of a Mozambican evergreen forest:a comparison of estimates based on regression equations and biomass expansion factors

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Forest Ecosystems 2016年第1期3卷 1-12页

作者： Tarquinio Mateus Magalhāes Departamento de Engenharia Florestal Universidade Eduardo MondlaneCampus Universitario

Background： Biomass regression equations are claimed to yield the most accurate biomass estimates than biomass expansion factors （BEFs）. Yet, national and regional biomass estimates are generally calculated based on BEFs, especially when using national forest inventory data. Comparison of regression equations based and BEF-based biomass estimates are scarce. Thus, this study was intended to compare these two commonly used methods for estimating tree and forest biomass with regard to errors and biases. Methods： The data were collected in 2012 and 2014. In 2012, a two-phase sampling design was used to fit tree component biomass regression models and determine tree BEFs. In 2014, additional trees were felled outside sampling plots to estimate the biases associated with regression equation based and BEF-based biomass estimates; those estimates were then compared in terms of the following sources of error： plot selection and variability, biomass model, model parameter estimates, and residual variability around model prediction. Results： The regression equation based below-, aboveground and whole tree biomass stocks were, approximately, 7.7, 8.5 and 8.3 % larger than the BEF-based ones. For the whole tree biomass stock, the percentage of the total error attributed to first phase （random plot selection and variability） was 90 and 88 % for regression- and BEF-based estimates, respectively, being the remaining attributed to biomass models （regression and BEF models, respectively）. The percent bias of regression equation based and BEF-based biomass estimates for the whole tree biomass stock were -2.7 and 5.4 %, respectively. The errors due to model parameter estimates, those due to residual variability around model prediction, and the percentage of the total error attributed to biomass model were larger for BEF models （than for regression models）, except for stem and stem wood components. Conclusions＂ The regression equation based biomass stocks were found to be slightly larg

关键词： Androstachysjohnsonii Prain Mecrusse Root growth Biomass additivity Double sampling Forest biomassinventory Carbon allocation

Proposals of SPT-CPT and DPL-CPT correlations for sandy soils in Brazil

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Journal of Rock Mechanics and Geotechnical Engineering 2017年第6期9卷 1152-1158页

作者： Mirella Dalvi dos Santos Kátia Vanessa Bicalho universidade Federal do Espírito Santo VitóriaBrazil

Field tests in geotechnical engineering are fundamental for identification of the underground *** standard penetration test(SPT) is the most commonly used geotechnical approach. There has been an increase both in the use and application of the in situ tests: cone penetration test(CPT) and dynamic probing(DP). Several empirical SPT-CPT and dynamic probing light(DPL)-CPT correlations for sandy soils have been discussed in the literature. New SPT-CPT and DPL-CPT correlations for the sandy soils of the city of Vitoria, in the southeast of Brazil, are suggested in this paper. Statistical analyses to evaluate the quality of the data used are performed, and the suggested correlations are validated with several previous published datasets. The paper also provides some insights into SPT-CPT correlations and soil characteristics(i.e. the mean particle size and the fines fraction of the soil).

关键词： Standard penetration test(SPT) Cone penetration test(CPT) Dynamic probing light(DPL) Correlations Sands Statistical evaluations

Charged scalar fields in a Kerr-Sen black hole:exact solutions, Hawkingradiation, and resonant frequencies

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Chinese Physics C 2019年第3期43卷 91-98页

作者： H.S.Vieira V.B.Bezerra Departamento de Física Universidade Federal da Paraíba

In this study, we consider charged massive scalar fields around a Kerr-Sen spacetime. The radial and angular parts of the covariant Klein-Gordon equation are solved in terms of the confluent Heun function. From the exact radial solution, we obtain the Hawking radiation spectrum and discuss its resonant frequencies. The massless case of the resonant frequencies is also examined.

关键词： Klein-Gordon equation charged and rotating black hole heterotic string field theory confluent Heun function black hole physics

Enhancing production monitoring: A back allocation methodology to estimate well flow rates and assist well test scheduling

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Petroleum Research 2024年第3期9卷 369-379页

作者： G.S.Chaves V.J.M.Ferreira Filho universidade Federal Do Rio de Janeiro Brazil

Production flow rates are crucial to make operational decisions,monitor,manage,and optimize oil and gas *** rates also have a financial importance to correctly allocate production to fiscal purposes required by regulatory agencies or to allocate production in fields owned by multiple *** its significance,usually only the total field production is measured in real time,which requires an alternative way to estimate wells'*** address these challenges,this work presents a back allocation methodology that leverages real-time instrumentation,simulations,algorithms,and mathe-matical programming modeling to enhance well monitoring and assist in well test *** methodology comprises four modules:simulation,classification,error calculation,and *** modules work together to characterize the flowline,wellbore,and reservoir,verify simulation outputs,minimize errors,and calculate flow rates while honoring the total platform flow *** well status generated through the classification module provides valuable information about the current condition of each well(*** the well is deviating from the latest well test parameters),aiding in decision-making for well testing scheduling and *** effectiveness of the methodology is demonstrated through its application to a representative offshore oil field with 14 producing wells and two years of daily production *** results highlight the robustness of the methodology in properly classifying the wells and obtaining flow rates that honor the total platform flow ***,the methodology supports well test scheduling and provides reliable indicators for well *** uti-lizing real-time data and advanced modeling techniques,this methodology enhances production monitoring and facilitates informed operational decision-making in the oil and gas industry.

关键词： Production estimation Real-time production Production monitoring Back allocation Well test scheduling Flow rate estimation

New exotic charmonium states

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Chinese Physics C 2010年第9期34卷 1157-1162页

作者： M.Nielsen Instituto de Física Universidade de So Paulo

In the last years many states in the charmonium mass region were discovery by BABAR,Belle and CDF collaborations.I discuss some of these discoveries,and how the QCD Sum Rule approach can be used to understand the stru... 详细信息

关键词： non-perturbative methods heavy mesons spectroscopy exotic mesons

Ophthalmic manifestations in patients with inflammatory bowel disease: a review

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World Journal of Gastroenterology 2017年第32期23卷 5836-5848页

作者： Leandro Lopes Troncoso Ana Luiza Biancardi Haroldo Vieira de Moraes Jr Cyrla Zaltman Department of Ophthalmology Universidade Federal do Rio de Janeiro Department of Internal Medicine Gastroenterology DivisionUniversidade Federal do Rio de Janeiro

Clinical manifestations of inflammatory bowel disease(IBD) are not locally restricted to the gastrointestinal tract, and a significant portion of patients have involvement of other organs and systems. The visual system is one of the most frequently affected, mainly by inflammatory disorders such as episcleritis, uveitis and scleritis. A critical review of available literature concerning ocular involvement in IBD, as it appears in Pub Med, was performed. Episcleritis, the most common ocular extraintestinal manifestation(EIM), seems to be more associated with IBD activity when compared with other ocular EIMs. In IBD patients, anterior uveitis has an insidious onset, it is longstanding and bilateral, and not related to the intestinal disease activity. Systemic steroids or immunosuppressants may be necessary in severe ocular inflammation cases, and control of the underlying bowel disease is important to prevent recurrence. Our review revealed that ocular involvement is more prevalent in Crohn's disease than ulcerative colitis, in active IBD, mainly in the presence of other EIMs. The ophthalmic symptoms in IBD are mainly nonspecific and their relevance may not be recognized by the clinician; most ophthalmic manifestations are treatable, and resolve without sequel upon prompt treatment. A collaborative clinical care team for management of IBD that includes ophthalmologists is central for improvement of quality care for these patients, and it is also cost-effective.

关键词： Inflammatory bowel disease Crohn's disease Ulcerative colitis Ocular complications Eye manifestations

Polymeric and biological membranes for organ-ona-chip devices

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Microsystems & Nanoengineering 2023年第4期9卷 19-43页

作者： Kendra Corral-Nájera Gaurav Chauhan Sergio OSerna-Saldívar Sergio OMartínez-Chapa Mohammad Mahdi Aeinehvand School of Engineering and Science Tecnológico de MonterreyAve.Eugenio Garza Sada 2501Monterrey 64849Mexico

Membranes are fundamental elements within organ-on-a-chip(OOC)platforms,as they provide adherent cells with support,allow nutrients(and other relevant molecules)to permeate/exchange through membrane pores,and enable the delivery of mechanical or chemical *** OOC platforms,physiological processes can be studied in vitro,whereas OOC membranes broaden knowledge of how mechanical and chemical cues affect cells and *** with membranes are in vitro microfluidic models that are used to replace animal testing for various applications,such as drug discovery and disease *** this review,the relevance of OOCs with membranes is discussed as well as their scaffold and actuation roles,properties(physical and material),and fabrication methods in different organ *** purpose was to aid readers with membrane selection for the development of OOCs with specific applications in the fields of mechanistic,pathological,and drug testing *** stimulation from liquid flow and cyclic strain,as well as their effects on the cell’s increased physiological relevance(IPR),are described in the first *** review also contains methods to fabricate synthetic and ECM(extracellular matrix)protein membranes,their characteristics(e.g.,thickness and porosity,which can be adjusted depending on the application,as shown in the graphical abstract),and the biological materials used for their *** discussion section joins and describes the roles of membranes for different research purposes and their advantages and challenges.

关键词： testing replace porosity

Proposal of a fireproof design code for dwellings against the action of wildland fires

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Resilient Cities and Structures 2023年第3期2卷 104-119页

作者： M.R.T.Arruda A.R.A.Bicelli P.Cantor E.B.Assis F.Branco CERIS Instituto Superior TécnicoUniversidade de LisboaPortugal Escola de Engenharia de São Carlos Universidade de São PauloBrazil Instituto Superior Técnico Universidade de LisboaPortugal

This study proposes a concept for the development of a fireproof design code for the verification of dwellings susceptible to wildfire *** are currently structural codes for the design of buildings when subjected to indoor fires,outside fires that grow on the facade of buildings,and even fires in an accident situation due to ignitions with hydrocarbons or transportation *** of these security verification specifications are described in EC1:*** current regulation in Portugal uses safety criteria and risk categories that are for indoor fires,therefore is very conservative and may not present an economic fireproof design against the action of *** aim of this work is a straight verification based on natural temperature characteristic curves that simulate wildfire heat flow by convection,radiation,and the deposits of firebrands.

关键词： Structural safety verification Wildfires in dwellings Nominal fires vs natural fires Fireproof construction guidelines

U-Pb provenance fingerprints of metavolcanic-sedimentary successions of the Mineiro belt:Proxies for the continuity of plate tectonics through the Paleoproterozoic

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Geoscience Frontiers 2022年第5期13卷 309-335页

作者： W.Teixeira C.A.Ávila I.A.Dussin E.Bongiolo Instituto de Geociências Universidade de São PauloBrazil Museu Nacional Universidade Federal do Rio de JaneiroBrazil Faculdade de Geologia Universidade do Estado do Rio de JaneiroBrazil Programa de Pós-graduação em Geociências Instituto de GeociênciasUniversidade Federal do Rio Grande do SulBrazil

We document new U-Pb detrital zircon LA-MC-ICP-MS data for seven metavolcanic-sedimentary successions and metasedimentary sequences and reassess additional dates of five siliciclastic samples toward their tectonic significance in the context of the Mineiro belt,Southern São Francisco *** belt represents a crustal segment of the 2.47–2.00 Ga Minas Orogen,classically known by its Siderian and Rhyacian juvenile rocks with important implications in the Earth’s *** new and compiled detrital provenance constraints unravel the long-lived magmatic and sedimentary history of the studied basins,lasting ca.230–220 *** maximum depositional dates around 2.1 Ga reflect the renewed sediment budget with the subsequent metamorphic episode ca.2.0 *** of the unmixed relative probability diagrams are consistent with sourcing from the Siderian and Rhyacian arcs of the Mineiro belt,determining a detrital provenance change in time and space for the precursor *** potential sources could be the youngest rocks of the Mantiqueira and Juiz de Fora terranes that constitute the other segments of the Minas Orogen,given the age *** overall detrital fingerprints determine the study basins resumed mainly in Rhyacian fore-arc and/or back-arc settings,i.e.,akin to a subductionrelated system that evolved to a collisional(foreland)*** samples show fingerprints of primary extensional settings,determined by major Archean detrital populations sourced from areas outside the Mineiro belt beside the Paleoproterozoic *** working model considers the collage between the Mineiro belt and the ancient foreland around 2.10 Ga and eventual interaction with other crustal segments of the Minas Orogen,generating the ca.2.0 Ga metamorphism over the metasedimentary *** more complete isotopic repository in detrital and igneous zircon grains for the studied supracrustal successions and the associated rocks allows new insights into the Rhyacian–Oro

关键词： Paleoproterozoic São Francisco Craton Detrital zircon geochronology Metavolcanic-sedimentary basin