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Improving wood volume predictions in dry tropical forest in the semi-arid Brazil

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Journal of Arid Land 2020年第6期12卷 1046-1055页

作者： Robson B de LIMA Patrícia A B BARRETO-GARCIA Alessandro de PAULA Jhuly E S PEREIRA flávia F de carvalho Silvio H M gomes Department of Forest Engineering State University of AmapáMacapá68900070Brazil Department of Forest Science State University of Southwest BahiaVitória da Conquista 45083900Brazil Universidade Federal de Lavras Lavras 37200900Brazil Universidade de São Paulo Piracicaba 13418900Brazil

The volumetric variability of dry tropical forests in Brazil and the scarcity of studies on the subject show the need for the development of techniques that make it possible to obtain adequate and accurate wood volume estimates.In this study,we analyzed a database of thinning trees from a forest management plan in the Contendas de SincoráNational Forest,southwestern Bahia State,Brazil.The data set included a total of 300 trees with a trunk diameter ranging from 5 to 52 cm.Adjustments,validation and statistical selection of four volumetric models were performed.Due to the difference in height values for the same diameter and the low correlation between both variables,we do not suggest models which only use the diameter at breast height(DBH)variable as a predictor because they accommodate the largest estimation errors.In comparing the best single entry model(Hohenald-Krenn)with the Spurr model(best fit model),it is noted that the exclusion of height as a predictor causes the values of 136.44 and 0.93 for Akaike information criterion(AIC)and adjusted determination coefficient(R2 adj),which are poorer than the second best model(Schumacher-Hall).Regarding the minimum sample size,errors in estimation(root mean square error(RMSE)and bias)of the best model decrease as the sample size increases,especially when a larger number of trees with DBH≥15.0 cm are randomly sampled.Stratified sampling by diameter class produces smaller volume prediction errors than random sampling,especially when considering all trees.In summary,the Spurr and Schumacher-Hall models perform better.These models suggest that the total variance explained in the estimates is not less than 95%,producing reliable forecasts of the total volume with shell.Our estimates indicate that the bias around the average is not greater than 7%.Our results support the decision to use regression methods to build models and estimate their parameters,seeking stratification strategies in diameter classes for the sample trees.Volume estimates with valid confidence intervals

关键词： volume modeling minimal sample size Caatinga Spurr model forest management

Sticky-MARTINI as a reactive coarse-grained model for molecular dynamics simulations of silica polymerization

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npj Computational Materials 2022年第1期8卷 467-479页

作者： AndréP.carvalho Sérgio M.Santos Germán Pérez-Sánchez JoséD.Gouveia JoséR.B.gomes Miguel Jorge CICECO-Aveiro Institute of Materials Department of ChemistryUniversity of AveiroCampus Universitário de Santiago3810-193AveiroPortugal Department of Chemical and Process Engineering University of Strathclyde75 Montrose StreetGlasgowG11XJUK

We report a molecular modeling paradigm to describe silica polymerization reactions in aqueous solutions at conditions that are representative of realistic experimental processes like biosilicification or porous silica synthesis–i.***.at close to ambient temperatures and over a wide range of pH.The key point is to describe the Si-O-Si chemical bond formation and breakage processes through a continuous potential with a balance between attractive and repulsive interactions between suitably placed virtual sites and sticky particles.The simplicity of the model,its applicability in standard parallelized molecular dynamics codes,and its compatibility with the widely used MARTINI coarse-grained force-field allows for the study of systems containing millions of atoms over microsecond time scales.The model is calibrated to match experimental results for the temporal evolution of silica polymerization in aqueous solution close to the isoelectric point,and can describe silica polymerization and self-assembly processes during encapsulation of a surfactant micelle.

关键词： silica polymerization dynamics

Ecophysiology and multivariate analysis for production of Tachigali vulgaris in Brazil:Influence of rainfall seasonality and fertilization

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林业研究:英文版 2023年第5期34卷 1289-1305页

作者： Pedro Henrique Oliveira Simoes Candido Ferreira de Oliveira Neto Manoel Tavares de Paula Dênmora gomes de Araújo Rodrigo Silva do Vale Joao Olegário Pereira de carvalho Universidade Federal de Mato Grosso Campus Universitario de SinopSinop 78550728Mato GrossoBrazil Universidade Federal Rural da Amazonia Campus BelemBelem 66077830ParaBrazil Universidade do Estado do Para Centro de Ciencias Naturais e TecnologiaBelem 66095015ParaBrazil Universidade Federal Rural da Amazonia Campus Capitao-PocoCapitao Poco 68650000ParaBrazil

Studies on fertilization management of species native to the Amazon for energy plantations contribute to the diversity of species use and reduce biological risk due to the excessive use of clones or hybrids of Eucalyptus.This study evaluates the effect of precipitation seasonality and phosphorus and potassium fertilization on gas exchange in a Tachigali vulgaris plantation.Three levels of P(zero,65.2,130.4 kg ha^(-1))and three of K(zero,100.0,200.0 kg ha^(-1))were applied in a 3×3 factorial randomized block design.Gas exchange measurements were conducted in April and November 2018.In low rainfall,high irradiance period,photo synthetic rates were up to four times higher than in the high rainfall period,reaching 20.3μmol m^(-2)s^(-1)in the treatment with 130.4 g kg^(-1)of P and 100.0 g kg^(-1)of K.Factor analysis and principal component analysis reduced the initial eight gas exchange variables to two and three principal components in periods of high and low rainfall,respectively.The multivariate method used in this study readily identified variations in the variables as a function of rainfall,with high reliability in explaining the data set.

关键词： Photosynthesis rate Stomatal conductance Principal component analysis Factor analysis Tachigali vulgaris

Supergiant Barocaloric Effects in Acetoxy Silicone Rubber over a Wide Temperature Range:Great Potential for Solid-state Cooling

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Chinese Journal of Polymer Science 2020年第9期38卷 999-1005,I0008页

作者： William Imamura Erik Oda Usuda Lucas Soares Paixao Nicolau Molina Bom Angelo Marcio gomes Alexandre Magnus gomes carvalho Faculdade de Engenharia Mec(a)nica UNICAMPCEP 13083-860CampinasSPBrazil Universidade Federal de Sāo Paulo UNIFESPCEP 09913-030DiademaSPBrazil Instituto de Física Gleb Wataghin UNICAMPCEP 13083-859CampinasSPBrazil Catalan Institute of Nanoscience and Nanotechnology ICN208860 BelaterraBarcelonaSpain The Institute of Photonic Sciences ICFO08193 CastelldefelsBarcelonaSpain Instituto de Física UFRJCEP 21941-972Rio de JaneiroRJBrazil Departamento de Engenharia Mec(a)nica UEMCEP 87020-900MaringáPRBrazil

Solid-state cooling based on caloric effects is considered a viable alternative to replace the conventional vapor-compression refrigeration systems.Regarding barocaloric materials,recent results show that elastomers are promising candidates for cooling applications around room-temperature.In the present paper,we report supergiant barocaloric effects observed in acetoxy silicone rubber—a very popular,low-cost and environmentally friendly elastomer.Huge values of adiabatic temperature change and reversible isothermal entropy change were obtained upon moderate applied pressures and relatively low strains.These huge barocaloric changes are associated both to the polymer chain rearrangements induced by confined compression and to the first-order structural transition.The results are comparable to the best barocaloric materials reported so far,opening encouraging prospects for the application of elastomers in near future solid-state cooling devices.

关键词： Solid-state cooling Barocaloric effect Elastomer Silicone rubber Crystalline-amorphous transition

Antinociceptive and anti-inflammatory activities of leaf extracts from Annona tomentosa R.E.Fr

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Journal of Integrative Medicine 2017年第5期15卷 379-387页

作者： Lilian Uchoa Carneiro Ilna gomes da Silva Mirian Eliza Alves de Souza Wellington da Silva Cortes Mário Geraldo de carvalho Bruno Guimaraes Marinho Postgraduate Program in Physiological Sciences Institute of Biological and Health SciencesFederal Rural University of Rio de JaneiroRio de Janeiro 23890-000Brazil Laboratory of Pharmacology Department of Physiological SciencesInstitute of Biological Sciences and HealthFederal Rural University of Rio de JaneiroRio de Janeiro 23890-000Brazil Postgraduate Program in Chemistry Department of ChemistryInstitute of Exact SciencesFederal Rural University of Rio de JaneiroRio de Janeiro 23890-000Brazil

OBJECTIVE：Annona tomentosa R.E.Fr is a species not endemic to Brazil that belongs to the phytogeographic areas of the Amazon,Cerrado and Pantanal.Popularly known as“araticum rasteiro”or“araticum de moita”,A.tomentosa is edible and tea made from the leaves has been used as an antiinflammatory by native communities.There is no scientific evidence for these uses of A.tomentosa,especially those related to the control of pain and inflammation.For this reason,in the present study we evaluated the antinociceptive and anti-inflammatory activities of partitions from the methanolic extract of A.tomentosa leaves（A.tomentosa leaf methanolic extract（ATFM）in hexane partition：ATFM-H;ATFM in dichloromethane partition：ATFM-D;ATFM in ethyl acetate partition：ATFM-Ac;ATFM in butanol partition：ATFM-B）in mice.METHODS：The antinociceptive effects of leaf extracts from A.tomentosa were evaluated by abdominal writhing and tail-flick tests,while the anti-inflammatory effects were evaluated by paw oedema and air-pouch tests.The locomotor activity was evaluated with the open-field test.Furthermore,we evaluated the possible action mechanism of A.tomentosa,using naloxone,nitro-L-arginine methyl ester,glibenclamide,atropine,naltrindole and norbinaltorphimine in tail-flick tests.The productions of tumor necrosis factorα（TNF-α）and interleukin（IL）-1βwere also evaluated.RESULTS：The chromatographic fractionation of the partitions of the methanolic extract from the leaves of A.tomentosa revealed the presence of diterpenes,flavonoids,and steroids compounds.From the analysis of the hexane partition kaurenoic acid was identified as the major component.ATFM-H and ATFM-D had a significant antinociceptive effect in acute pain models in mice.The ATFM-H showed central antinociceptive effect from the involvement of theδopioid receptors,without causing alterations in the locomotor activity of the mice,while ATFM-D was effective in decreasing paw oedema and TNF-α and IL-1β production.CONCLUSION：These results demonstrate that leaf extracts from A.tomentosa prese

关键词： Annona tomentosa cytokines opioid nociception

Effects of Five Years Adoption of No-Tillage Systems for Vegetables Crops in Soil Organic Matter Contents

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Agricultural Sciences 2018年第1期9卷 117-128页

作者： Carlos E. P. Lima ítalo M. R. Guedes Juscimar da Silva flávia A. alcantara Nuno R. Madeira Agnaldo D. F. carvalho Mariana R. Fontenelle Embrapa Hortaliç as CNPH Brasília Brazil

Vegetables productions systems are done normally with intense soil tillage causing a strong decline of soil quality. Use of conservation systems can be an alternative to recover this quality. In order to evaluate the effects of such systems on soil organic matter, an experiment has been conducted in randomized blocks design and factorial scheme 3 × 2: three soil management systems (no-tillage;reduced tillage and conventional tillage) and two cover crops (maize single;and intercropping maize with gray velvet bean—Stizolobium niveum);and repeated measures over time. Soil samples were collected before the implementation of the experiment and at the end of each crop cycle until the fifth crop cycle. Carbon associated with humic substances is also determined in 0 - 5 cm, 5 - 10 cm and 10 - 30 cm at the end of the last crop cycle. The SOM content was higher in RT (48.34 g·kg-1) than in the CT (39.48 g·kg-1) at the end of the fifth crop cycle. SOM content in NT (44.92 g·kg-1) was statistically equal to RT and CT, during the same period. In 0 - 5 cm, carbon contents associated to the humic substances present the same behavior of SOM contents in 0 - 10 cm. Probably these results are associated with the capacity of each system to improve superficial contents of SOM stable fractions. It follows that the conservation systems used are alternatives to the cultivation vegetables in order to improve soil organic matter contents.

关键词： No-Tillage Reduced Tillage Soil Conservation Soil Management

Mesenchymal stem cell secretome and nanotechnology:Combining therapeutic strategies

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BIOCELL 2022年第8期46卷 1807-1813页

作者： ADRIANA L.FERREIRA GUSTAVO C.PARIS ALINE DE A.AZEVEDO ERIKA A.C.CORTEZ SIMONE N.carvalho LAIS DE carvalho ALESSANDRA A.THOLE Laboratory of Stem Cell Research Roberto Alcantara Gomes Biology InstituteRio de Janeiro State UniversityRio de Janeiro20540170Brazil

Mesenchymal stem cells(MSC)have pushed the field of stem cell-based therapies by inducing tissue regeneration,immunosuppression,and angiogenesis mainly through vesicles and soluble factors release(paracrine signaling).MSC-extracellular vesicles(MSC-EV)adaptable secretome and homing to injured sites allowed researchers to unlock a new era of cell-free based therapy.In parallel,nanoparticles(NP)have been explored in contributing to transport and drug delivery systems,giving drugs desired physical-chemical properties to exploit cell behavior.However,NPs can be quickly recognized by immune cells and cleared from circulation.In this viewpoint,we explore how combining both therapeutic strategies can improve efficacy and circumvent limitations of both therapies.MSCEV benefit from the potent MSC membrane composition,guiding chemotaxis to tumor sites,a very restricted microenvironment.MSC-EV has low immunogenicity,high stability,long half-life and can explore tissue targeting ligands as a precise drug carry,even across biological barriers.Those properties promote enhanced targeted drug delivery that can be combined with NP,exploring biological membrane production through:1.direct cell therapy with NP-infused MSC;2.NP-containing MSC-EV generated by NP-infused MSC;3.by coating NP in MSC membrane(“MSC NanoGhosts”),allowing precise cargo definition without losing targeting.Therefore,nanotechnology combined with cell-based therapeutic resources can greatly improve targeted drug delivery,improving efficacy and opening a new venue of therapeutic possibilities.

关键词： Mesenchymal stem cells Nanoparticles Secretome Exosome Targeted drug delivery

CYP1A1,CYP2E1 and EPHX1 polymorphisms in sporadic colorectal neoplasms

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World Journal of Gastroenterology 2016年第45期22卷 9974-9983页

作者： Glaucia Maria M Fernandes Anelise Russo Marcela alcantara Proenca Nathalia Fernanda Gazola Gabriela Helena Rodrigues Patrícia Matos Biselli-Chicote Ana Elizabete Silva Joao gomes Netinho érika Cristina Pavarino Eny Maria Goloni-Bertollo Genetics and Molecular Biology Research Unit-UPGEM Department of Molecular Biology Sao José do Rio Preto Medical School FAMERP Departament of Biology UNESP-Sao Paulo State University Departament of Surgery and Coloproctology Service Sao José do Rio Preto Medical School FAMERP

AIM To investigate the contribution of polymorphisms in the CYP1A1, CYP2E1 and EPHX1 genes on sporadic colorectal cancer(SCRC) risk. METHODS Six hundred forty-one individuals(227 patients with SCRC and 400 controls) were enrolled in the study. The variables analyzed were age, gender, tobacco and alcohol consumption, and clinical and histopathological tumor parameters. The CYP1A1 *2A, CYP1A1 *2C CYP2E1 *5B and CYP2E1 *6 polymorphisms were analyzed by polymerase chain reaction-restriction fragment length polymorphism(PCR-RflP). The EPHX1 Tyr113 His, EPHX1 His139 Arg and CYP1A1 *2C polymorphisms were detected by real-time PCR. Chisquared test and binary logistic regression were used in the statistical analysis. Haplotype analysis was conducted using the Haploview program, version 2.05.RESULTS Age over 6 2 years was a risk factor for SCRC development(OR = 7.54, 95%CI: 4.94-11.50, P < 0.01). Male individuals were less susceptible to SCRC(OR = 0.55, 95%CI: 0.35-0.85, P < 0.01). The CYP2E1*5B polymorphism was associated with SCRC in the codominant(heterozygous genotype: OR = 2.66, 95%CI: 1.64-4.32, P < 0.01), dominant(OR = 2.82, 95%CI: 1.74-4.55, P < 0.01), overdominant(OR = 2.58, 95%CI: 1.59-4.19, P < 0.01), and log-additive models(OR = 2.84, 95%CI: 1.78-4.52, P < 0.01). The CYP2E1*6 polymorphism was associated with an increased SCRC risk in codominant(heterozygous genotype: OR = 2.81, 95%CI: 1.84-4.28, P < 0.01; homozygous polymorphic : OR = 7. 3 2, 9 5 % C I : 1.85-28.96, P < 0.01), dominant(OR = 2.97, 95%CI: 1.97-4.50, P < 0.01), recessive(OR = 5.26, 95%CI: 1.35-20.50, P = 0.016), overdominant(OR = 2.64, 95%CI: 1.74-4.01, P < 0.01), and log-additive models(OR = 2.78, 95%CI: 1.91-4.06, P < 0.01). The haplotype formed by the minor alleles of the CYP2E1*5B(C) and CYP2E1*6(A) polymorphisms was associated with SCRC(P = 0.002). However, the CYP1A1 *2A, CYP1A1 *2C, EPHX1 Tyr113 His and EPHX1 His139 Arg polymorphisms were not associated with SCRC.CONCLUSION In conclusion, the results demonstrated that CYP2E1*5B and CYP2E1*6

关键词： Single-nucleotide polymorphisms Colorectal neoplasms Cytochrome P-450 CYP2E1 Cytochrome P-450 CYP1A1 Epoxide hydrolases 1

Waste Tire Rubber-based Refrigerants for Solid-state Cooling Devices

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Chinese Journal of Polymer Science 2020年第7期38卷 769-775,I0007页

作者： Nicolau Molina Born Erik Oda Usuda Mariana da Silva Gigliotti Denílson JoséMarcolino de Aguiar William Imamura Lucas Soares Paixao Alexandre Magnus gomes carvalho Catalan Institute of Nanoscience and Nanotechnology(ICN2) 08860BellaterraBarcelonaSpain The Institute of Photonic Sciences(ICFO) 08193CastelldefelsBarcelonaSpain Universidade Federal de Sāo Paulo(UNIFESP) 00972-270DiademaSPBrazil Instituto de Física"Gleb Wataghin" Universidade Estadual de Campinas(UNICAMP)13083-970CampinasSPBrazil Universidade Tecnológica Federal do Paraná(UTFPR) 84017-220Ponta GrossaPRBrazil Faculdade de Engenharia Mec(a)nica Universidade Estadual de Campinas(UNICAMP)13083-860CampinasSPBrazil Departamento de Engenharia Mec(a)nica Universidade Estadual de Maringá(UEM)870-900MaringáPRBrazil

Management of discarded tires is a compelling environmental issue worldwide.Although there are several approaches developed to recycle waste tire rubbers,their application in solid-state cooling is still unexplored.Considering the high barocaloric potential verified for elastomers,the use of waste tire rubber(WTR)as a refrigerant in solid-state cooling devices is very promising.Herein,we investigated the barocaloric effects in WTR and polymer blends made of vulcanized natural rubber(VNR)and WTR,to evaluate its feasibility for solid-state cooling technologies.The adiabatic temperature changes and the isothermal entropy changes reach giant values,as well as the performance parameters,being comparable or even better than most barocaloric materials in literature.Moreover,pure WTR and WTR-based samples also present a faster thermal exchange than VNR,consisting of an additional advantage of using these discarded materials.Thus,the present findings evidence the encouraging perspectives of employing waste rubbers in solid-state cooling based on barocaloric effects,contributing to both the recycling of polymers and the sustainable energy technology field.

关键词： Waste tire rubber Solid-state cooling Barocaloric effect Tire recycling Sustainable energy