Sabiia Seb
PortuguêsEspañolEnglish
Embrapa
        Busca avançada

Botão Atualizar


Botão Atualizar

Ordenar por: 

RelevânciaAutorTítuloAnoImprime registros no formato resumido
Registros recuperados: 41
Primeira ... 123 ... Última
Imagem não selecionada

Imprime registro no formato completo
Air drying of macauba fruits: maintaining oil quality for biodiesel production Agronomy
Silva, Gutierres Nelson; Grossi, José Antônio Saraiva; Carvalho, Marcela Silva; Kuki, Kacilda Naomi; Goulart, Samuel de Melo; Pimentel, Leonardo Duarte.
Macauba fruits are oil-rich drupes with high moisture content at harvest. This feature can affect the chemical properties of the oil and increase the costs of biodiesel production. Therefore, it is necessary to adopt postharvest strategies to ensure oil quality. The aim of this work was to evaluate the effect of drying macauba fruit on the quality of the pulp oil. Husked and dehusked fruits were dried at 60°C and then stored. At 0, 15, 45, 100, and 180 days after storage, fruit samples were retrieved, and the oil from the pulp was evaluated for physicochemical parameters. The removal of the husk from the fruits considerably reduced the drying time compared to that of the husked fruits. Drying prevented deterioration of the fruit even after 180 days of...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Acrocomia aculeata; Post-harvest; Storage; Bioenergy; Armazenamento de Produtos Agrícolas.
Ano: 2019 URL: http://periodicos.uem.br/ojs/index.php/ActaSciAgron/article/view/43451
Imagem não selecionada

Imprime registro no formato completo
Arbuscular mycorrhizal fungi action on the quality of strawberry fruits Horticultura Brasileira
Cordeiro,Ely Cristina N; Resende,Juliano Tadeu V de; Córdova,Katielle Rosalva V; Nascimento,Daniele Aparecida; Saggin Júnior,Orivaldo José; Zeist,André Ricardo; Favaro,Renata.
ABSTRACT The inoculation of arbuscular mycorrhizal fungi (AMF), increasing the rhizospheric influence, might provide higher levels of bioactive compounds. Thus, the objective was to evaluate the influence of the AMF inoculation on the physicochemical components of fruit’s quality in field. Strawberry fruits from cultivars Camarosa, Aromas, Camino Real, Monterey, Portola, San Andreas and Albion in 2016, and Camarosa, Camino Real, Monterey and Albion in 2017 were either inoculated or non-inoculated with AMF. The analyzed physicochemical components of fruit’s quality were ascorbic acid, titrated acidity, pH, soluble solids, soluble solids/titrated acidity ratio, phenolic compounds, anthocyanins, and firmness. The inoculation with AMF on strawberry plants in...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Fragaria x ananassa; Mycorrhiza; Inoculation; Post-harvest.
Ano: 2019 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-05362019000400437
Imagem não selecionada

Imprime registro no formato completo
CASTOR BEANS QUALITY SUBJECTED TO DIFFERENT STORAGE TEMPERATURES AND PERIODS REA
Goneli,André L. D.; Corrêa,Paulo C.; Oliveira,Ana P. L. R.; Hartmann Filho,Cesar P.; Oba,Guilherme C..
ABSTRACT The control of the temperature of the storage air have the ability to improve a better preservation of some types of agricultural products. However, the most effective temperature for storage as well as the duration of storage varies between products. Therefore, special attention should be concentrated on the storage temperature and its effects on the integrity and longevity of the produce. The objective of the present study was to evaluate the effects of storage temperature and storage period on the quality of castor beans. Castor seeds with a water content of approximately 6.1% (w.b.) were stored for 180 days at temperatures of 15, 25 and 35 °C. The quality of the seeds was evaluated every 45 days throughout the study period by measuring dry...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Armazenability; Ricinus communis L.; Post-harvest.
Ano: 2018 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162018000300361
Imagem não selecionada

Imprime registro no formato completo
CHEMICAL AND PHYSICAL CHARACTERISTICS OF ‘IMPROVED SUNRISE SOLO LINE 72-12’ PAPAYA FRUITS SUBMITTED TO DIFFERENT MECHANICAL DAMAGE Rev. Bras. Frutic.
SALOMÃO,LUIZ CARLOS CHAMHUM; CECON,PAULO ROBERTO; AQUINO,CÉSAR FERNANDES; LINS,LEILA CRISTINA ROSA DE; BRAGA,LUCIANO RIBEIRO.
ABSTRACT This study aimed to evaluate some changes in the metabolism of papaya fruits submitted to damage by impact, abrasion and compression. Injuries were caused in two areas of 15 cm2 each; in diametrically opposite positions in the equatorial region of ‘Improved Sunrise Solo Line 72/12’ papaya fruits in ripening stage 3 (fruits with 25-40% of yellow skin). After damage, fruits were stored at 15 ± 1 °C and 85 ± 5% RH, and samples were taken at intervals of two days to evaluate skin color index, incidence of diseases, loss of fresh weight, leak of solutes, pulp firmness, soluble solids content and pectinmethylesterase and polygalacturonase activities. The respiratory rate was measured at intervals of 4, 8, 12, 24, 48 and 72 hours after damage. The...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Carica papaya L.; Impact; Abrasion; Compression; Post-harvest.
Ano: 2016 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-29452016000400301
Imagem não selecionada

Imprime registro no formato completo
conservation and nutritional quality of blueberry treated with eatable covering Ciência e Agrotecnologia
Stülp,Marcibela; Gnas,Bruna Barbara Bucalão; Clemente,Edmar.
Lengthening the post-harvest life of fruits from temperate climates is one of the greatest challenges of modern agriculture, which aims at diminishing the losses and increasing the offer period of the product in national and international market. The use of eatable pellicles has been explored to cover fruits, since its usage represents an economical advantage, due to its low price and reduction of post-harvest losses. Thus, the aim of this work was to evaluate the quality of blueberry, cultivar Florida M, produced in an organic production system and covered with eatable covering based on kefir grains associated with different storage temperatures. Thus, it was observed that the most efficient treatment to reduce blueberry post-harvest loss was the...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Post-harvest; Blueberry; Kefir.
Ano: 2014 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1413-70542014000400006
Imagem não selecionada

Imprime registro no formato completo
Cultura de helicônias. Infoteca-e
PAIVA, W. O. de.
Processo produtivo; custos com a implantacao; custos operacionais; rendimento; bibliografia consultada.
Tipo: Circular Técnica (INFOTECA-E) Palavras-chave: Cultivo; Heliconias; Culture; Production; Post-harvest; Investment.; Helicônia; Floricultura; Investimento; Pós-Colheita; Rendimento.; Produção; Floriculture; Income..
Ano: 1998 URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/421832
Imagem não selecionada

Imprime registro no formato completo
DEFORMATION OF PEACHES SUBMITTED TO CYCLIC LOADING USING THE DISCRETE ELEMENT METHOD REA
Pinto,Eduardo M.; Ferraz,Antonio C. de O..
ABSTRACT This study aimed to use and validate a simple contact force model that describes the behavior of peaches stored in a wooden box, loaded cyclically, by using the discrete element method. The Kelvin-Voigt contact force model was used and the cyclic loading in the simulation was performed with an amplitude of 1 mm and frequency of 12 Hz for time intervals of 3600, 5400, and 7200 s. The laboratory test was performed with a peach box attached to a vibrating table by applying the same excitation conditions used in the simulation. For validation, model results were compared with those from the laboratory test by using deformation values of fruits in the contact regions. To measure this deformation, we adapted the methodology for determining the radius of...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Modeling; Simulation; Post-harvest; Prunus persica (L.) Batsch.
Ano: 2018 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162018000300434
Imagem não selecionada

Imprime registro no formato completo
Efficiency of boron application in an Oxisol cultivated with banana in the Central Amazon Anais da ABC (AABC)
Moreira,Adônis; Castro,César de; Fageria,Nand K..
In the Amazon region, there is no information on the fertilization of banana plants with boron (B). Besides this, the extractant (hot water) currently used to test B concentrations has many limitations. The aim of this work was to study the effect of B on the fruit yield and quality of banana plants of the Cavendish (AAA) sub-group, grown in dystrophic Yellow Latosol (Oxisol or Xanthic Ferralsol), in the Amazonas State, Brazil. The experimental design was completely randomized split plot in a 4 x 2 factorial scheme, composed of four B rates (0, 4, 8 and 12 kg ha-1) and two harvest cycles (sub-treatments), with four replicates. The B availability in the soil was determined by three extractants: Mehlich 3, hot water and KCl 1.0 mol L-1. The application of B...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Musa spp.; Yield; Methods of soil analysis; Post-harvest.
Ano: 2010 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652010000400030
Imagem não selecionada

Imprime registro no formato completo
Establishment of intercropping of beet and chicory depending on soil management Rev. Ciênc. Agron.
Coutinho,Pablo Wenderson Ribeiro; Oliveira,Paulo Sérgio Rabello de; Echer,Márcia de Moraes; Cadorin,Danielle Acco; Vanelli,Jaqueline.
ABSTRACT This study aimed to evaluate the productivity and quality characteristics of beet and chicory based on management of straw and intercropping period of establishment. The experiment was conducted in the organic horticulture sector of Unioeste, in a design of randomized blocks with four replications, where the treatments were arranged in 2 x 5 and 2 x 8 factorial schemes. The first factorial consisted of the straw mulch management (with and without incorporation of the gray velvet bean straw) and the intercropping period of establishments and beet and chicory monocrops (0; 7; 14 and 21 days after transplanting beet). The second factorial was composed of the straw mulch management (with and without incorporation) and the cultivation of chicory...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Beta vulgaris; Cichorium endívi; Vegetal cover; Yield; Post-harvest.
Ano: 2017 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1806-66902017000400674
Imagem não selecionada

Imprime registro no formato completo
Ethylene and 1-methylcyclopropene action over senescence of nasturtium flowers Horticultura Brasileira
Silva,Tania P; Finger,Fernando L.
ABSTRACT: This work describes ethylene and 1-methylcyclopropene (1-MCP) action on post-harvest shelf life of four development stages of nasturtium flowers. To reach this goal, we carried out three experiments. In the first and second experiments, we studied five ethylene (0; 0.1; 1; 10; 100 and 1000 μL/L) and three 1-MCP concentrations (0.25; 0.5 and 0.75 μL/L), respectively. In the third experiment, 1-MCP was followed by combined with ethylene (only 1-MCP; only ethylene; and 24 hours of exposure to 0.75 μL/L 1-MCP followed by 24 hours of exposure to 100 μL/L ethylene). All experiments had two control treatments, one keeping non-exposed flowers inside and another outside exposure chambers. Experiments were set in factorial design, in complete blocks at...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Tropaeolum majus; Phytohormone; Post-harvest; Phenological stages..
Ano: 2015 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-05362015000400453
Imagem não selecionada

Imprime registro no formato completo
Farmers' Post-Harvest Grain Management Choices under Liquidity Constraints and Impending Risks: Implications for Achieving Food Security Objectives in Ethiopia AgEcon
Gabriel, Abebe H.; Hundie, Bekele.
The purpose of this paper is to explore into the relationships between farmers' post-harvest grain management practices/capacities on the one hand, and liquidity constraints and impending risks on the other, in the context of achieving food security objective at household and national levels. The findings are primarily based on a household survey data from 300 randomly selected major food grain producing peasant households in three rural districts of Ethiopia. Results indicate that farmers perceived post-harvest grain loss as an imminent risk, and that instant sales of grains after harvest are triggered by temporary but immediate liquidity preferences to meet various obligations in the absence of or limited sources of cash other than crops sales, and by an...
Tipo: Conference Paper or Presentation Palavras-chave: Post-harvest; Liquidity; Risk; Grain loss; Grain sales; Price fluctuations; Crop Production/Industries; Food Security and Poverty; Q12; Q13; Q18.
Ano: 2006 URL: http://purl.umn.edu/25716
Imagem não selecionada

Imprime registro no formato completo
Fruit quality of ‘Eva’ e ‘Princesa’ apples grown under nitrogen fertigation in semiarid climate AGRIAMBI
Miranda,João M. de S.; Cavalcante,Ítalo H. L.; Oliveira,Inez V. de M.; Lopes,Paulo R. C.; Assis,Joston S. de.
ABSTRACTThe production of high quality fruits is a necessary factor for the adaptation and production of plant species with economic viability. Thus, an experiment was conducted from July 2012 to January 2013 to evaluate the fruit quality of the ‘Eva’ and ‘Princesa’ apple cultivars as a function of nitrogen fertilization in Petrolina, PE, Brazil. The experimental design consisted of randomized blocks, with treatments distributed in a factorial arrangement 2 x 4, corresponding to apple cultivars (Eva and Princesa) and nitrogen doses (40; 80; 120 and 160 kg of N ha-1), with four replications and three plants in each plot. The fruit characteristics, such as fruit mass, skin color (luminosity, chromaticity, and colour angle), size (width and length), pulp...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Malus domestica; Nitrogen; Post-harvest.
Ano: 2015 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662015001000967
Imagem não selecionada

Imprime registro no formato completo
Gamma radiation in papaya harvested at three stages of maturation Scientia Agricola
Pimentel,Rodrigo Meirelles de Azevedo; Walder,Julio Marcos Melges.
Papaya is a fragile, perishable fruit, highly accepted worldwide. To keep the quality of papaya from harvest to the consumers, conservation techniques are often used; among them is the application of gamma irradiation. The objective of this work was to evaluate gamma irradiation in papayas harvested at three degrees of maturation, in order to increase shelf life. Papayas were harvested in perfect quality conditions and selected by skin coloration into three distinct degrees of maturation: maturation 0, or beginning of yellow coloration; maturation 1, yellow stripes more developed, and maturation 2, one third yellow. Half of them were irradiated with 0.75 kGy, while the other half became control treatment. They were analyzed in four periods of conservation,...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Post-harvest; Food conservation; Gamma irradiation; Tropical fruits; Shelf life.
Ano: 2004 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162004000200004
Imagem não selecionada

Imprime registro no formato completo
Incidence of aflatoxins in pre and post harvested corn Thai Agricultural
Prisnar Hemsuchi; Arunsri Wong-Urai; Dara Buangsuwon.
2 tables
Palavras-chave: Corn; Maize; Aflatoxins; Pre-harvest; Post-harvest; Fungi; ข้าวโพด; อะฟลาทอกซิน; วิทยาการก่อนการเก็บเกี่ยว; วิทยาการหลังการเก็บเกี่ยว; เชื้อรา.
Ano: 1981 URL: http://anchan.lib.ku.ac.th/agnet/handle/001/4051
Imagem não selecionada

Imprime registro no formato completo
Incidência fúngica e contaminações por micotoxinas em grãos de híbridos comerciais de milho em função da umidade de colheita - DOI: 10.4025/actasciagron.v31i4.5690 Agronomy
Marques, Odair José; UEM; Vidigal Filho, Pedro Soares; UEM; Dalpasquale, Valdecir Antoninho; UEM; Scapim, Carlos Alberto; UEM; Pricinotto, Luiz Fernando; UEM; Machinski Júnior, Miguel; UEM.
O objetivo deste trabalho foi avaliar a incidência de fungos dos gêneros Aspergillus, Fusarium e Penicillium e as contaminações com micotoxinas em grãos de cinco híbridos comerciais de milho em função da umidade de colheita. O trabalho foi conduzido em Astorga, Estado do Paraná, durante o período da ‘safrinha’ de 2007 e da safra de ‘verão’ de 2007/2008. As amostras de grãos, colhidas em cinco épocas distintas e em cinco repetições, foram submetidas à determinação de umidade pelo método da estufa a 103 ± 1ºC por 72h. O teste de sanidade Blotter test e a quantificação micotoxinas (método da cromatografia em camada delgada) foram efetuados, utilizando-se um delineamento inteiramente casualizado. Os resultados obtidos foram submetidos à análise de...
Tipo: Pesquisa Empírica de Campo Palavras-chave: 5.01.03.04-0 Produção de Mudas Zea mays L.; Pós-colheita; Qualidade; Aflatoxinas; Zearalenona Fitotecnia Zea mays L.; Post-harvest; Quality; Aflatoxins; Zearalenone.
Ano: 2009 URL: http://periodicos.uem.br/ojs/index.php/ActaSciAgron/article/view/5690
Imagem não selecionada

Imprime registro no formato completo
Isolation and HPLC quantitation of kaurane-type diterpenes and cinnamic acid derivatives of long-term stored leaves of Mikania laevigata and Mikania glomerata Anais da ABC (AABC)
BERTOLUCCI,SUZAN K.V.; PEREIRA,ANA B.D.; PINTO,JOSE E.B.P.; OLIVEIRA,ALAIDE B.; BRAGA,FERNAO C..
The leaves of Mikania laevigata and Mikania glomerata are used in Brazil to treat respiratory affections, being kaurane-type diterpenes and coumarin considered as the bioactive compounds. The present study reports an investigation on the HPLC-DAD profiles and contents of coumarin (1), trans-o-coumaric (2), kaurenoic (3), benzoylgrandifloric (4) and cinnamoylgrandifloric (5) acids in dried leaves of Mikania species stored in dark room under controlled conditions. Excepting 2, the constituents were isolated and purified to be employed as reference compounds. The samples were analyzed at three monthly intervals up to 18 months for M. laevigata and 12 months for M. glomerata. trans-o-Coumaric was not detected in both, whereas 1 occurred only in M. laevigata....
Tipo: Info:eu-repo/semantics/article Palavras-chave: Chemical markers changes; HPLC-DAD analysis; Mikania laevigata; Mikania glomerata; Storage; Post-harvest.
Ano: 2013 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652013000200473
Imagem não selecionada

Imprime registro no formato completo
Jute Retting Process: Present Practice and Problems in Bangladesh CIGR Journal
Ali, Md. Rostom; Kozan, Osamu; Rahman, Anisur; Islam, Khandakar Tawfiq; Hossain, Md. Iqbal.
Jute retting process is one of the important responsible factors for quality of jute fiber. Scarcity of jute retting water in some areas of Bangladesh is one of the major issues. The main purpose of this study was provided information about the status of present jute retting process as well as mentioned the advantages and disadvantages of different jute retting processes. Data about traditional jute retting process and ribbon retting process were collected through personal interview from the jute growers. The farmers are involved in jute cultivation and majority of them use the traditional method and time consuming approach of retting in ponds/canals. The traditional method hampers the quality of the jute fiber, fish cultivation and pollutes the...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Post-harvest; Jute retting; Environment Jute retting; Water shortage; Environment; Ribbon retting; And Quality fiber.
Ano: 2015 URL: http://www.cigrjournal.org/index.php/Ejounral/article/view/3212
Imagem não selecionada

Imprime registro no formato completo
Maintenance pruning in physalis commercial production Bragantia
D’angelo,Jessica Welinski de Oliveira; Bastos,Marília Camotti; Cuquel,Francine Lorena.
ABSTRACT Due to field and literature divergences about the best management of physalis (Physalis peruviana L.), this paper aimed to verify the effect of maintenance pruning on the productivity and quality of its fruit. The plants were submitted to 4 different ways of management during their entire cycle: (i) no stem pruning; (ii) keeping only 4 stems; (iii) keeping 6 stems; and (iv) keeping 8 stems. The sampling began 80 days after transplantation (DAT) of the seedlings and it was executed weekly, totaling 7 evaluations. The results demonstrated that pruned plants produced higher caliber fruits. However, the plants that did not receive pruning were the most productive. Therefore, as long as the price of physalis fruit is a matter of quantity and not of...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Physalis peruviana L.; Post-harvest; Small fruits; Culture management.
Ano: 2017 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87052017000200214
Imagem não selecionada

Imprime registro no formato completo
Manual transportation within the plot and physical damages to bananas Scientia Agricola
Magalhães,Mário Jorge Maia de; Abrahão,Roberto Funes; Leal,Paulo Ademar Martins.
The manual transportation of banana bunches within plots provokes physical damages to fruits compromising their quality. To assess the influence of the distance banana bunches travel on the shoulders of harvesters within the plot, on the incidence of physical damages present on the peel of fruits of the Nanicão cultivar, two experiments were carried out in the Vale do Ribeira region (SP), in sites with slope < 1%. Each experiment divided the plot in different distance bands, two of which were included in this study: one located far away from the collection roads (30-50 m and 80-100 m distance bands) and another in an intermediate position (70-80 m and 130-150 m distance bands). For each distance band, six banana bunches of 36 mm gauged fruits were...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Musa cavendish; Harvesting bananas; Post-harvest; Mechanical damages.
Ano: 2004 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162004000100006
Imagem não selecionada

Imprime registro no formato completo
Modeling of the shrinkage kinetics of coffee berries during drying - doi: 10.4025/actasciagron.v33i3.7080 Agronomy
Oliveira, Gabriel Henrique Horta; Instituto Federal de Brasília; Corrêa, Paulo Cesar; Universidade Federal de Viçosa; Botelho, Fernando Mendes; Universidade Federal de Mato Grosso; Goneli, André Luis Duarte; Universidade Federal da Grande Dourados; Afonso Júnior, Paulo Cesar; Embrapa Café; Campos, Sílvia Carvalho; EMBRAPA Agrosilvipastoril.
The effects of drying conditions on the shrinkage of Coffea Arabica L., cultivar Catuaí Vermelho, were studied. An exponential model derived from the kinetic model was used to describe the shrinkage kinetics. In addition, an equation was proposed to describe the relationship between the superficial areas and weights of the coffee berries. Coffee berries were dried at temperatures (T) of 35, 45, 55 and 65ºC and at relative humidities (φ) of 25, 35, 45 and 55%, forming 16 different sets of conditions, with an initial moisture content for all conditions of 2.27 dry basis (d.b.), dried until 0.11 d.b. Changes in the product dimensions were measured continuously during drying. Surface area-to-volume ratio values increased with moisture content decrease. The...
Palavras-chave: 5.00.00.00-4; 5.03.00.00-8; 5.03.03.02-3 surface area-to-volume ratio; Post-harvest; Activation energy; Coffea arabica L; Shrinkage Ciências Agrárias; Engenharia Agrícola; Armazenamento de Produtos Agrícolas surface area-to-volume ratio; Post-harvest; Activation energy; Coffea arabica L; Shrinkage.
Ano: 2011 URL: http://periodicos.uem.br/ojs/index.php/ActaSciAgron/article/view/7080
Registros recuperados: 41
Primeira ... 123 ... Última
 

Empresa Brasileira de Pesquisa Agropecuária - Embrapa
Todos os direitos reservados, conforme Lei n° 9.610
Política de Privacidade
Área restrita

Embrapa
Parque Estação Biológica - PqEB s/n°
Brasília, DF - Brasil - CEP 70770-901
Fone: (61) 3448-4433 - Fax: (61) 3448-4890 / 3448-4891 SAC: https://www.embrapa.br/fale-conosco

Valid HTML 4.01 Transitional