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Litter decomposition and nutrient release for two tropical N-fixing species in Rio de Janeiro,Brazil

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Journal of Forestry Research 2022年第2期33卷 487-496页

作者： David Pessanha Siqueira Giovanna Campos Mamede Weiss de Carvalho joséGabriel de souza Silva Marcos Vinicius Winckler Caldeira deborah Guerra Barroso Laboratório de Fitotecnia Universidade Estadual do Norte Fluminense Darcy RibeiroAvenida Alberto Lamego2000Campos dos GoytacazesRio de JaneiroBrazil departamento de Ciências Florestais e da Madeira Universidade Federal do Espírito SantoAvenida Governador Lindenberg316Jerônimo MonteiroEspírito SantoBrazil department of Geosciences and Natural Resources Management University of CopenhagenRolighedsvej 23Frederisksberg CDenmark

Litter production and decomposition are critical to forest productivity,nutrient cycling,and carbon seques-tration in tropical woody ***,nutrient release and leaf litter stoichiometry in tropical legume tree plantations over the long term after outplanting are poorly understood or even *** improving our under-standing of the pattern of changes in the decomposition of N-fixing leaf litters and their possible impact on carbon stor-age,we measured litter production,mass loss and nutrient release for 240 d during litter decomposition for two tropical legume tree species(Plathymenia reticulata and Hymenaea courbaril),in Rio de Janeiro,*** production for *** was 5.689 kg ha^(−1) a^(−1) and 3.231 kg ha^(−1) a^(−1) for *** patterns of mass loss rates were similar;however,nutrient release was greater for ***,while *** showed immobilization of nutrients,especially for N,which increased by almost 20%in the early phase of decomposition followed by gradual *** from the N-fixing species did differ in nutrient chemistries over time,which was not surprising given that initial nutrient concentrations varied broadly,except for C and *** of the nutrient concentrations increased as the remaining litter mass decreased in both species,except for C and *** C:N and N:P ratios differed between the species,but N:P did not correlate to mass *** species had N-rich leaves,but *** decomposition was very likely P-limited,while *** seemed to be co-limited by N and *** results showed different patterns in nutrient release and the stoichi-ometry involved in the decomposition dynamics of the two tropical N-fixing species,even though they have similar litter decay *** species,but especially ***,may help re-establish nutrient cycling in disturbed ecosystems.

关键词： Nutrient dynamics Legume species Litter chemistry Ecological stoichiometry Tropical forest

Vegetative propagation of Apuleia leiocarpa(Vogel)***

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Journal of Forestry Research 2022年第2期33卷 455-462页

作者： joséGabriel de souza Silva Diêgo Faustolo Alves Bispo David Pessanha Siqueira Giovanna Campos Mamede Weiss de Carvalho deborah Guerra Barroso Laboratório de Fitotecnia Universidade Estadual do Norte Fluminense Darcy RibeiroAvenida Alberto LamegoCampos dos GoytacazesRJ 2000Brazil

Apuleia leiocarpa is an environmentally and economically significant Atlantic Forest species threat-ened by ongoing *** vegetative propagation of the species could be a step forward to enable implanta-tion of clonal seed orchards and multiplication of selected trees but remains unknown to *** study assessed the mini-cutting technique for propagation of *** and determined the time required for rooting and viable mini-cutting type and *** results show that it is possible to propagate *** with mini-cuttings derived from mini-stumps produced with seeds;the mini-stumps pre-sented regrowth capacity and remained constantly produc-tive for 1 year;10-cm *** mini-cuttings should remain under misting conditions for at least 40 days,and the vegetative propagation of *** with intermediate 7-to 10-cm mini-cuttings resulted in more vigorous clonal seedlings than smaller mini-cuttings.

关键词： Mini-cutting Tropical woody species Adventitious rooting Fabaceae

Near-infrared leaf reflectance modeling of Annona emarginata seedlings for early detection of variations in nitrogen concentration

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Journal of Forestry Research 2023年第1期34卷 269-282页

作者： Rafaela Lancas Gomes Marília Caixeta Sousa Felipe Girotto Campos Carmen Sílvia Fernandes Boaro josé Raimundo de souza Passos Gisela Ferreira Bioestatistic Plant BiologyParasitology and Zoology DepartmentBioscience Institute(IBB)Universidade Estadual Paulista(UNESP)BotucatuSao PauloBrazil

Nitrogen(N)monitoring is essential in nurseries to ensure the production of high-quality *** spectroscopy(NIRS)is an instantaneous,nondestructive method to monitor *** data such as NIRS can also provide the basis for developing a new vegetation spectral index(VSI).Here,we evaluated whether NIRS combined with statistical modeling can accurately detect early variations in N concentration in leaves of young plants of Annona emargiaata and developed a new VSI for this *** were grown in a hydroponics system with 0,2.75,5.5or 11 mM N for 45 *** we measured gas exchange,chlorophylla fluorescence,and pigments in leaves;analyzed complete leaf nutrients,and recorded spectral data for leaves at 966 to 1685 nm using *** a statistical learning approach,the dimensionality of the spectral data was reduced,then models were generated using two classes(N deficiency,N)or four classes(0,2.75,5.5,11 mM N).The best combination of techniques for dimensionality reduction and classification,respectively,was stepwise regression(PROC STEPDISC)and linear discriminant *** was possible to detect N deficiency in seedlings leaves with 100%precision,and the four N concentrations with93.55%accuracy before photosynthetic damage to the plant ***,NIRS combined with statistical modeling of multidimensional data is effective for detecting N variations in seedlings leaves of ***.

关键词： Mineral nutrition of plants Near-infrared spectroscopy Spectral vegetation index Digital signature Statistical learning Fluorescence of chlorophylla

Tribologically induced nanostructural evolution of carbon materials: A new perspective

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Friction 2024年第1期12卷 144-163页

作者： Guilherme Oliveira NEVES Nicolás ARAYA Diego Berti SALVARO Thiago de souza LAMIM Renan Oss GIACOMELLI Cristiano BINdeR Aloisio Nelmo KLEIN joséDaniel Biasoli de MELLO Laboratório de Materiais Universidade Federal de Santa CatarinaSanta Catarina 88040-900Brazil departamento de Ingeniería Mecánica Facultad de IngenieríaUniversidad del Bío-BíoConcepcion 4070-386Chile Universidad de Concepción Concepcion 4070-386Chile SENAI Innovation Institute for Laser Processing Santa Catarina 89218-153Brazil Universidade Federal de Uberlândia Minas Gerais 38408-100Brazil

Carbon-based solid lubricants are excellent options to reduce friction and wear,especially with the carbon capability to adopt different allotropes *** the macroscale,these materials are sheared on the contact along with debris and contaminants to form tribolayers that govern the tribosystem *** a recently developed advanced Raman analysis on the tribolayers,it was possible to quantify the contactinduced defects in the crystalline structure of a wide range of allotropes of carbon-based solid lubricants,from graphite and carbide-derived carbon particles to multi-layer graphene and carbon *** addition,these materials were tested under various dry sliding conditions,with different geometries,topographies,and solid-lubricant application *** of the initial tribosystem conditions and allotrope level of atomic ordering,there is a remarkable trend of increasing the point and line defects density until a specific saturation limit in the same order of magnitude for all the materials tested.

关键词： carbon nanostructures tribology Raman spectroscopy defects quantification tribolayer solid lubrication

A numerical assessment of two geometries for reducing elbow erosion

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Particuology 2020年第2期18卷 117-133页

作者： Carlos Antonio Ribeiro Duarte Francisco joséde souza Diego Nei Venturi Martin Sommerfeld department of Engineering Federal University of Goiás-Regional Catal(a)oAv.Dr.Lamartine Pinto de Avelar1120Catal(a)oGoiásBrazil School of Mechanical Engineering Federal University of Uberl(a)ndiaAv.Joāo Naves de(A)vila2121 Bloco 5PUberl(a)ndiaMinas GeraisBrazil Multiphase Flow Systems(MPS) Otto-von-Guericke-University MagdeburgZeppelinstraβe 1D-06130 Halle(Saale)Germany

Elbows in pneumatic conveying systems are normally prone to the erosive effects of conveyed *** are a number of solutions available to reduce such damage.A widely used geometric alternative for replacing the 90°elbow and reducing erosive wear is the plugged *** option,although less commonly used,is the vortex-chamber *** both cases,the effective reduction in erosion brought about is unclear,as it strongly depends on the operating *** present study assesses relative erosion among the plugged tee,vortex-chamber elbow,and standard elbow for a dilute gas-solid multiphase flow.A numerical model is employed to predict the penetration ratio and validated using experimental data for the plugged *** are run for the standard and vortex-chamber elbows and plugged tee under the same conditions to compare the mechanics involved and the relative erosion *** analysis uses variables relating to particle-wall interactions(impact angle,impact velocity,impact frequency)to illustrate the nature of the erosive process in each pipe *** general,the geometric configurations of both the plugged tee and vortex-chamber elbow promote changes in particle dynamics that reduce the rate of *** the basis of the relative erosion of the standard elbow,the plugged tee proves to be an interesting option in cases of a low mass loading,while the vortex-chamber elbow demonstrates its erosion reduction potential for higher mass loading ***,the advantages and disadvantages of each fitting are highlighted.

关键词： Relative erosion Plugged tee Erosion reduction Pipe fitting Computational fluid dynamics

Starch Orodispersible Film Loaded with Melatonin for Human Supplementation

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Journal of Renewable Materials 2024年第7期12卷 1343-1354页

作者： Fabio Tamanini Tatiane Zucchini de souza Creusa Sayuri Tahara Amaral Antônio joséFelix Carvalho Eliane Trovatti department of Health and Biological Sciences University of Araraquara(UNIARA)São Paulo14801-340Brazil department of Materials Engineering São Carlos School of EngineeringUniversity of São PauloSão Paulo13563-120Brazil

An innovative pharmaceutical form for administering melatonin,based on starch orodispersibleﬁlm(ODF),was designed and *** composition of the ODF included starch as the polymer matrix,the active drug melatonin,and a ***,a natural hormone produced by the pineal gland in the brain,can be absorbed by passive diffusion across the mucous membrane,resulting in improved bioavailability when compared to conventional oral *** study shows a simple and efﬁcient method for preparing melatonin-loaded orodispersibleﬁlms with a physically stable and commercially viable matrix,suitable for use in the pharmaceutical ***ﬁlms were prepared by treating the starch with microwave irradiation,followed by plasticization with glycerol,melatonin loading and drying by solvent *** tests showed theﬁlms’robustness,with a modulus of approximately 97 MPa,indicating good handling *** uptake analysis showed fast water absorption,reaching about 150%within 2 min,indicating its fast oral disintegration *** tests in artiﬁcial saliva and dissolution studies indicated the release of the drug in min-utes,indicating the potential properties of theﬁlm for oral drug *** the best of our knowledge,there is no melatonin ODF based on starch described in the literature.

关键词： Starch orodispersibleﬁlm melatonin drug delivery

Gain of transcription factor binding sites is associated to changes in the expression signature of human brain and testis and is correlated to genes with higher expression breadth

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Science China(Life Sciences) 2019年第4期62卷 526-534页

作者： Vandeclécio Lira da Silva André Mauricio Ribeiro dos Santos Wilfredo Blanco Sandro josé de souza Bioinformatics Multidisciplinary Environment (BioME) Universidade Federal do Rio Grande do Norte (UFRN) Programa de Pós-Gradua??o em Genética e Biologia Molecular (PPGBM) Universidade Federal do Pará (UFPA) department of Computer Science Universidade Estadual do Rio Grande do Norte (UERN) Brain Institute Universidade Federal do Rio Grande do Norte (UFRN)

The gain of transcription factor binding sites(TFBS) is believed to represent one of the major causes of biological *** we used strategies based on comparative genomics to identify 21,822 TFBS specific to the human lineage(TFBS-HS),when compared to chimpanzee and gorilla genomes. More than 40%(9,206) of these TFBS-HS are in the vicinity of 1,283 genes.A comparison of the expression pattern of these genes and the corresponding orthologs in chimpanzee and gorilla identified genes differentially expressed in human tissues. These genes show a more divergent expression pattern in the human testis and brain, suggesting a role for positive selection in the fixation of TFBS gains. Genes associated with TFBS-HS were enriched in gene ontology categories related to transcriptional regulation, signaling, differentiation/development and nervous ***, genes associated with TFBS-HS present a higher expression breadth when compared to genes in general. This biased distribution is due to a preferential gain of TFBS in genes with higher expression breadth rather than a shift in the expression pattern after the gain of TFBS.

关键词： TFBS transcript factor human evolution expression breadth

Dynamics in the emergence of dormant and non-dormant herbaceous species from the soil seed bank from a Brazilian dry forest

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Journal of Plant Ecology 2020年第3期13卷 256-265页

作者： josé Djalma de souza Bruno Ayron de souza Aguiar Danielle Melo dos Santos Vanessa Kelly Rodrigues de Araujo Júlia Arruda Simões Juliana Ramos de Andrade Elcida de Lima Araújo departamento de Biologia Universidade Federal Rural de PernambucoRecifePernambucoBrazil2Universidade Federal de Pernambuco-Centro Acadêmico de VitóriaPernambucoBrazil

在干旱的热带森林中,草本植物可能具有休眠机制,并在土壤中形成持续和短暂的种子库。这一由进化而获得的机制对草本植物的建植和生存,特别是在气候不可预测的森林生态系统中,具有重要生态适应意义。因此,本研究的目的是验证草本植物是... 详细信息

在干旱的热带森林中,草本植物可能具有休眠机制,并在土壤中形成持续和短暂的种子库。这一由进化而获得的机制对草本植物的建植和生存,特别是在气候不可预测的森林生态系统中,具有重要生态适应意义。因此,本研究的目的是验证草本植物是否具备物理休眠机制,以及这些植物是如何克服这些自然屏障的,并最终理解巴西干旱热带森林土壤种子库中种子萌发时间动态。本研究选择巴西Caatinga森林中的5种本地草本植物的种子,经过发芽前处理来验证是否存在物理休眠。连续4年在雨季和旱季收集土壤样品,并监测这些草本植物种子在温室中的萌发动态。利用广义线性模型验证种子萌发和出苗率的差异。研究结果表明Caatinga森林中的草本植物种子存在着物理休眠和非物理休眠;而且草本植物从土壤种子库中出苗的种内和种间存在着年份和季节的差异。对于多年生草本植物,不同季节和年份频繁出现不出苗的现象,这可能与物理休眠机制和克服种皮障碍所需的环境条件有关。在这些物种中,种子的二态性和休眠可能给它们的生存带来额外的优势。此外,在一年生植物中出现中等水平的物理休眠可能是对降雨不可预测性的进化调整。相比之下,我们发现没有休眠的一年生草本植物对季节和年际气候变化更敏感,这可以从土壤种子库中其出苗率的增加和显著减少得到证明。这些通过进化获得的种子休眠差异有利于那些分布在气候变化无常的半干旱地区草本植物种群的建立。

关键词：草本植物半干旱种子萌发植株建立物理休眠

What is the effect of Tribulus terrestris on testicular morphology and sperm production?An experimental study in the rat model

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Asian Journal of Andrology 2024年第1期26卷 67-70页

作者： Marcello Henrique Araujo Da Silva Gabriela Faria Buys-Goncalves Joao Henrique Duque Reis Estrada Francisco jose Barcellos Sampaio Diogo Benchimol de souza Urogenital Research Unit Rio de Janeiro State UniversityRio de Janeiro 20551-030RJBrazil

The objective of this study was to investigate whether treatment with Tribulus terrestris(Tt)has any impact on the testicular morphology and function in a rodent *** male rats were divided into a control group and a group receiving 100 mg kg^(-1) body weight of Tt *** 4o days of experiment,the animals were submitted to euthanasia;epididymal tail spermatozoa were collected;and spermatozoa concentration,motility,and viability were *** addition,testicles were collected and processed for histomorphometrical *** were compared using the Student's t-test and considered significant when Pdensity,seminiferous epithelium surface density,and intertubular compartment surface density were statistically similar between the ***,seminiferous epithelium height and tubular lumen surface density were augmented in animals treated with *** with Tt does not cause a major impact on testicular morphology,promoting only subtle *** difference on spermatozoa parameters was observed.

关键词： morphometry testicle Tribulus terrestris