Mobiele bystandstelsels (MAS) beloof om die personeeltekorte in die operasiesaal wêreldwyd te oorkom. 'n Literatuuroorsig geïnspireer deur die PRISMA 2020 metode bepaal die stand van die kuns van MAS en identifiseer 'n gebrek aan toepassingsareas vir MAS in die operasieteater. Onderhoude met vakkundiges het ten doel om toepassingsareas vir MAS te ondersoek. Die resultate toon dat die meeste operasionele take na materiaalbestuur en pasiëntbestuur verwys. MAS met die potensiaal om die tyd in materiële en pasiëntbestuur te verminder, sowel as fisiese en geestelike spanning in pasiëntbestuur, het groot potensiaal in die operasieteater.

Mobile assistance systems (MAS) promise to overcome personnel shortages in operating theatres worldwide. A literature review inspired by the PRISMA 2020 method determines the state of the art of MAS, and identifies a lack of application areas for MAS in the operating theatre. Interviews with subject-matter experts aim to investigate application areas for MAS. The results show that most operational tasks refer to material management and patient management. MAS, with their potential to reduce the time needed for material and patient management, and the physical and mental strain of patient management, have great potential in the operating theatre.

Litografie-gebaseerde keramiekvervaardiging (LCM) is 'n laagvervaardigingstegnologie (LV) wat pasgemaakte, driedimensionele keramiekonderdele laag vir laag bou. Die vlak van akkuraatheid van die proses maak voorsiening vir die druk van pasgemaakte intern-aaneenlopende roosterstrukture en ontwerpe wat geskik is vir beenimplantate. Hierdie studie het die LCM-veraardigbaarheid van verskeie roosterstrukture ondersoek met die hidroksieapatiet (HA480) verskaf deur Lithoz. Verskillende roosterstrukture is gekarakteriseer. Die mikroskopiese struktuur, die samestelling en die oppervlakrofheid van die toetsmonsters is bepaal. Om die meganiese eienskappe van die strukture te verkry, is druktoetse uitgevoer. Die waargenome mikroporieë van ±3 µm en die makroporieë van ±320 µm was geskik vir beenselgroei. Die gemete mikrohardheid van HA480 was 556±25 HV in die bourigting en 559±27 HV loodreg op die bourigting. Die druksterkte van die rombiese dodekaëderroosterstruktuur was 4±0.5 MPa, en was beter as ander getoetste roosters. Uit die resultate is tot die gevolgtrekking gekom dat roosterstrukture wat deur LCM vervaardig word, die potensiaal het om gebruik te word vir vervaardiging van pasgemaakte beenregenererende steiers.

Lithography-based ceramic manufacturing (LCM) is an additive manufacturing (AM) technology that builds custom-designed, three-dimensional ceramic parts layer by layer. The level of precision of the process allows for the printing of custom-made interconnected lattices and designs suitable for bone implants. This study investigated the LCM printability of various lattice structures with the hydroxyapatite (HA480) supplied by Lithoz. Different lattice structures were characterised. The microscopic structure, the composition, and the surface roughness of the test specimens were determined. To obtain the mechanical properties of the structures, compression tests were performed. The observed micropores of ±3 µm and the macropores of ±320 µm were suitable for bone cell growth. The measured microhardness of HA480 was 556±25 HV in the built direction and 559±27 HV perpendicular to the built direction. The compressive strength of the rhombic dodecahedron lattice structure was 4±0.5 MPa, and was superior to other tested lattices. From the results it was concluded that lattice structures produced through LCM have the potential to be used to produce customised bone-regenerating scaffolds.

In the South African public healthcare sector, 28% of diabetic patients present to primary healthcare clinics with diabetic foot ulcers (DFUs), often presenting in advanced stages of ulcer severity. In this study, we aimed to categorise factors predisposing individuals to developing a DFU and to identify the potential shortcomings in existing treatment plans in the South African healthcare system. In addition, the use of preventative measures in the management of DFUs was examined as well as the influence of past treatment practices. A total minimum sample size of 50 DFUs was required for this study. Participants who were selected for this study had their past records reviewed in order to determine the likelihood of previous DFU infections, as well as to determine the occurrence of co-morbidities. The treatment protocol implemented was recorded. Twelve-month patient records were used to identify the infection frequency and past treatment protocols. A total of 48.9% of patients reported that they did not make use of any preventative measures. The most frequent concurrent medical conditions were hypertension, dyslipidaemia, and peripheral neuropathy. Polypharmacy was prevalent, with 55% of the population prescribed five or more medications. Potential medication interactions were examined and a total of 210 interactions were documented. An analysis of past and current treatment practices revealed that 52.1% of the treatment protocols did not comply with local treatment guidelines. This study highlights the urgent need for updated DFU treatment protocols in relation to the overall management of DFUs, taking into account existing international guidelines. SIGNIFICANCE: We determined that the South African treatment guidelines and DFU classification system do not align to international standards. Furthermore, the use of preventative measures among DFU patients was poor and polypharmacy was present in the patient cohort. We emphasise the need for all members of a healthcare team, including podiatrists, clinicians, microbiologists and pharmacists, to work together in order to identify at-risk patients, prevent possible DFUs and effectively treat existing DFUs in a manner that does not contribute to antimicrobial resistance and provides the best possible outcome for the patient.

INTRODUCTION: The Work Ability Screening Profile (WASP) was conceptualised and developed by occupational therapists at the University of Durban Westville to provide a basic vocational screening assessment. Its purpose was to screen competence in generic work skills which reflected performance in activities essential to workplace participation relevant to the South African context. The assessment was revised in 2005 and renamed the WASP II. It was decided this screening assessment tool would be continuously reviewed using action research with clinicians involved in the ongoing evaluation so ensure validity and reliability for the population with which it is used. This study considered the clinical evaluation, useability and utility of the WASP II in order to inform further revision. METHOD: A cross sectional survey was used to gather data from 70 occupational therapy clinicians familiar with or using the WASP II in clinical practice. RESULTS: A sample of 70 respondents indicated the WASP II was suitable to assess current work ability and production speed with a variety of clients with physical and mental health dysfunction. Ten of the 12 subtests were used by at least 40% of the time by the 28 respondents who used the WASP II frequently. These respondents reported good to adequate useability in terms of cost, sensitivity to clients' educational level and ease of understanding instructions, incorporation into clinical practice contexts while supporting clinical reasoning and judgement. The accommodation of clients' language and provision of standard scores were indicated as inadequate. Utility was considered adequate for all aspects including discrimination of moderate to severe dysfunction, informing the choice of other assessmentsas well as supporting vocational rehabilitation intervention. The WASP II outcomes were also understood by other service providers, employers, referring parties as well asclients. CONCLUSION: While the WASP II was considered appropriate for use in the South African context and has adequate useability and utility, some subtests need to be updated and revised in terms of the standard times and content validity for current practice in the work environment. IMPLICATIONS FOR PRACTICE: The WASP II has useability • aligned with generic work skills of acquiring information or following directions numeracy, conveying information and written communication • for with those with work experience and with scholars and students yet to enter the workplace The WASP II has utility in relation to • cost and clients' educational levels • detailed instructions on the task layout but some standardisation needs to be interpreted with care • sensitivity to all aspects of assessment of generic work skills, except discrimination of mild dysfunction

ABSTRACT Copper is an essential element for beet; however, it needs to be made available in adequate quantities since this nutrient, which is a heavy metal, can cause toxicity to plants and/or humans. This study aimed to evaluate the agronomic performance of beet fertigated with copper in a semi-arid region of Brazil. Two experiments were carried out in complete randomized blocks, with five treatments (0, 1.5, 3.0, 4.0, and 6.0 kg ha-1 of copper) and four replicates. In 2019, the copper content was within the adequate range for beet. In 2021, fertigation with copper above 0.8 kg ha-1 led to contents in the phytotoxicity range, which may explain the reduction in total and tuberous root dry mass accumulation. Fertilization with copper increased marketable yield in 2019 (17.32 t ha-1 at the dose of 3.9 kg ha-1 of copper), while, in 2021, there was no fit of the equations. Copper fertilization altered the tuberous root pH but did not influence the other tuberous root quality components. Plants fertilized with copper accumulated more copper in the leaves than in the tuberous root, with a maximum accumulation of 6.0 kg ha-1 of copper in 2019 and 2021. Fertilization with 3.9 kg ha-1 suits soils with low copper content.

RESUMO O cobre é um elemento essencial à beterraba, no entanto, é necessário disponibilizá-lo em quantidade adequada uma vez que esse nutriente, que é um metal pesado, pode causar toxicidade às plantas e, ou, ao ser humano. Esta pesquisa teve como objetivo avaliar o desempenho agronômico de beterraba fertirrigada com cobre em uma região semiárida do Brasil. Foram conduzidos dois experimentos em delineados em blocos casualizados ao acaso, com cinco tratamentos (0, 1.5, 3.0, 4.5 e 6.0 kg ha-1 de cobre) e quatro repetições. Em 2019, o teor de cobre estava dentro da faixa adequada para a beterraba. Em 2021, a fertirrigação com cobre acima de 0.8 kg ha-1 proporcionou teores na faixa de fitotoxicidade, o que pode explicar a redução no acúmulo de massa seca total e de raízes tuberosas. A adubação com cobre aumentou a produtividade comercial em 2019 (17.32 t ha-1 na dose de 3.9 kg ha-1 de cobre) enquanto que, em 2021, não houve modelo ajustado. A adubação alterou o pH da raiz tuberosa, mas não influenciou nos demais atributos de qualidade pós-colheita da raiz tuberosa. Plantas adubadas com cobre acumularam mais cobre nas folhas do que na raiz tuberosa, com máxima acumulada em 2019 e em 2021, na dose 6.0 kg ha-1 de cobre. A adubação com 3.9 kg ha-1 é adequada para solos com baixo teor de cobre.

ABSTRACT Cowpea is a crop of high socioeconomic importance for the semi-arid region of Brazil, although facing significant yield losses due to drought, requiring management strategies to overcome this scenario. From this perspective, this study aimed to evaluate the growth and yield of cowpea genotypes under drought in different cultivation systems. The statistical design was randomized blocks arranged in a 2 × 4 × 2 factorial scheme corresponding to two cowpea genotypes (BRS Pujante and Costela de Vaca), four levels of crop evapotranspiration (40, 60, 80, and 100%), and two cultivation systems (with and without soil mulching). The BRS Pujante showed a higher leaf area and 100-grain weight than Costela de Vaca under all levels of crop evapotranspiration. The cowpea yield parameters showed the best results at 80 and 100% crop evapotranspiration. Regardless of the genotype, soil mulching provided higher cowpea 100-grain weight values. Soil mulching combined with 80% crop evapotranspiration is an appropriate strategy for cowpea production.

RESUMO O feijão-caupi tem grande importância socioeconômica para o semiárido brasileiro, porém sofre perdas significativas de produção pelo estresse por seca, necessitando de estratégias de manejo para superar esse cenário. Nessa perspectiva, o presente estudo teve como objetivo avaliar o crescimento e a produção de genótipos de feijão-caupi sob estresse hídrico em diferentes sistemas de cultivo. O delineamento estatístico adotado foi o de blocos casualizados, em arranjo fatorial 2 × 4 × 2, correspondendo a dois genótipos de feijão-caupi (BRS Pujante e Costela de Vaca), quatro níveis de evapotranspiração da cultura (40, 60, 80 e 100%) e dois sistemas de cultivo (com e sem cobertura morta do solo). O genótipo de feijão-caupi BRS Pujante apresentou maior área foliar e peso de 100 grãos do que o genótipo Costela de Vaca em todos os níveis de evapotranspiração da cultura. Os parâmetros de produção do feijão-caupi apresentaram os melhores resultados a 80 e 100% da evapotranspiração da cultura. Independentemente do genótipo, a cobertura morta do solo proporcionou maiores valores de peso de 100 grãos de feijão-caupi. A cobertura do solo combinada com 80% da evapotranspiração da cultura é uma estratégia adequada para a produção de feijão-caupi.

ABSTRACT Although soybean is one of the most important agricultural commodities in the world, it has been losing genetic diversity in recent decades, due to the intense breeding process and reproduction method. Thus, the objective of this study was to evaluate the agronomic performance and estimate the genetic diversity among inbred lines, and identify promising crossings. A total of 66 soybean genotypes were evaluated, 61 of which were pre-commercial lines, and five commercial cultivars (AS3797, DESAFIO, M7110, M7739, M8210) as controls. The experimental design consisted of randomized blocks with three replicates. The distance matrix between the inbred lines was calculated by Mahalanobis distance and grouping by the unweighted pair group method with arithmetic mean (UPGMA). The maximum distance was 1,776.26 between cultivar M7110 and the G23 inbred line, and the minimum 1.50 between inbred lines G13 and G36, with an average distance of 364.40, demonstrating genetic diversity. The traits that contributed most to genetic divergence were number of days to flowering (66.7%) and physiological maturation (28.55%). Inbred lines G60 (higher grain yield), G51 and G33 (lower physiological maturation) and cultivar M7110 (greater divergence) stood out. Four groups were formed, with G1 having the highest grain yield and fewest days to flowering and physiological maturation. The indicated crossings are between G60, G57, CD2728, M7110, G33 and G32 (group G1) and G47 (group G4).

RESUMO A soja é uma das mais importantes comodities agrícolas mundiais, no entanto, devido ao intenso processo de melhoramento e sua forma de reprodução, vem perdendo diversidade genética ao longo das últimas décadas. Assim, o objetivo deste estudo foi avaliar o desempenho agronômico, estimar a diversidade genética entre as linhagens e identificar cruzamentos promissores. Para isto, foram avaliados 66 genótipos de soja, sendo 61 linhagens pré-comerciais e cinco cultivares comerciais (AS3797, DESAFIO, M7110, M7739, M8210) como controles. O delineamento experimental foi o de blocos ao acaso com três repetições. A matriz de distância entre as linhagens foi calculada pela distância de Mahalanobis e o agrupamento pelo método da ligação média entre grupos (UPGMA). A distância máxima foi de 1.776,26 entre as linhagens M7110 e G23, e a mínima de 1,50 entre as linhagens G13 e G36, sendo a distância média de 364,40, demonstrando a existência de diversidade genética. Os caracteres que mais contribuíram para a divergência genética foram número de dias para o florescimento (66,7%) e maturação fisiológica (28,55%). As linhagens G60 (maior produtividade de grãos), G51 e G33 (menor maturação fisiológica) e a cultivar M7110 (maior divergência) se destacaram. Formaram-se quatro grupos, sendo o grupo G1 com maior produtividade de grãos e menor número de dias para o florescimento e maturação fisiológica. Os cruzamentos indicados são entre G60, G57, CD2728, M7110, G33 e G32 (grupo G1) com a G47 (grupo G4).

ABSTRACT The semi-arid region faces problems related to water deficit and the presence of brackish water that compromise crop performance. Therefore, irrigation frequency can enhance the growth of agricultural crops of interest even under salt stress conditions. In this context, the objective of the present study was to evaluate different irrigation frequencies with water of higher and lower salinity on the agronomic performance of millet. The experiment was conducted from September to November 2020, in the experimental area of the Auroras Seedling Production Unit, belonging to the Universidade da Integração Internacional da Lusofonia Afro-Brasileira, Redenção, Ceará, Brazil. The experimental design used was completely randomized in a 4 × 2 factorial arrangement, with five repetitions. The first factor corresponded to four irrigation frequencies (F1 - daily irrigation; F2 - irrigation every two days; F3 - irrigation every three days; F4 - irrigation every four days) and the second factor consisted of two levels of electrical conductivity of irrigation water (0.3 and 5.0 dS m-1). Salt stress (5.0 dS m-1) negatively affected leaf area, plant height, stalk diameter, panicle length, and leaf, stem, panicle, and total dry mass of millet, under daily and four-day irrigation frequencies. Increasing the interval in irrigation frequency to beyond two days negatively affects the agronomic performance of millet crop, regardless of the electrical conductivity of water used (0.3 or 5.0 dS m-1). Under salt stress conditions, adopting irrigation frequencies between two and three days can be a viable alternative for irrigation management in pearl millet crop.

RESUMO A região semiárida apresenta problemas relacionados ao déficit hídrico e presença de água salobra que comprometem o desempenho das culturas. Assim, a frequência de irrigação pode promover melhores condições de desenvolvimento das culturas de interesse agrícola mesmo em condições de estresse salino. Neste sentido, objetivou-se avaliar diferentes frequências de irrigação com água de maior e menor salinidade sobre desempenho agronômico do milheto. O experimento foi realizado no período de setembro a novembro de 2020, na área experimental da Unidade de Produção de Mudas Auroras, pertencente a Universidade da Integração Internacional da Lusofonia Afro-Brasileira, Redenção, Ceará. O delineamento experimental utilizado foi inteiramente casualizado em arranjo fatorial 4 × 2, com cinco repetições. O primeiro fator corresponde a quatro frequências de irrigação (F1 - irrigação diária; F2 - irrigação a cada dois dias; F3 - irrigação a cada três dias; F4 - irrigação a cada quatro dias) e o segundo consistiu em dois níveis de condutividade elétrica da água de irrigação (0,3 e 5,0 dS m-1). O estresse salino (5,0 dS m-1) afetou negativamente a área foliar, altura da planta, diâmetro do colmo, comprimento da panícula, massa seca da folha, caule, panícula e total do milheto, sob irrigação diária e cada quatro dias. O aumento do intervalo na frequência de irrigação acima de dois dias afeta o desempenho agronômico do milheto, independente da condutividade elétrica da água (0,3 ou 5,0 dS m-1). Em condições de estresse salino, adotar frequências de irrigação entre dois e três dias pode ser uma alternativa viável para o manejo da irrigação do milheto.

ABSTRACT The need for studies that allow the use of brackish water in irrigated agriculture and the socioeconomic importance of melon cultivation in Brazil, especially for the Northeast region, which concentrates most of the national production and faces problems with the availability of good quality water for irrigation, motivated the present study. In this context, the objective of present study was to evaluate the growth, production and fruit quality of the ‘Goldex’ (yellow-type hybrid F1) melon under salt stress conditions. The experiment was performed in a completely randomized design, with two salinity levels of irrigation water (0.8 and 4.0 dS m-1) and eight evaluation times (52, 54, 56, 58, 60, 62, 64, and 66 days after transplanting). Variables of plant growth and development, production and quality of melon fruits were evaluated throughout the cycle. Plants had delayed growth characteristics and less development with the increase in irrigation water salinity, showing reductions of more than 20% in shoot dry weight, leaf area, number of branches and length of secondary branches and 16.7% in length of the main branch. In addition, salinity caused a delay in fruit development and a 16% reduction in final fruit weight, without significantly modifying carbohydrate and total soluble solids contents. Along the development, there was an increase in the total soluble solids content of the fruits, especially due to the increment of sucrose at the final stages of development.

RESUMO A necessidade de estudos que possibilitem a utilização de águas salobras na agricultura irrigada e a importância socioeconômica da cultura do melão no Brasil, especialmente para a região Nordeste, que concentra a maior parte da produção nacional e apresenta problemáticas com disponibilidade de água de boa qualidade para irrigação, norteou o presente estudo. Nesse contexto, o objetivo do presente estudo foi avaliar o crescimento das plantas, a produção e a qualidade de frutos do híbrido de melão amarelo ‘Goldex’ (híbrido F1 tipo amarelo) sob condições de estresse salino. A pesquisa foi conduzida em delineamento inteiramente casualizado, contendo dois níveis de salinidade da água de irrigação (0,8 e 4,0 dS m-1) e oito épocas de avaliação (52, 54, 56, 58, 60, 62, 64 e 66 dias após o transplantio). Foram avaliadas variáveis de crescimento e desenvolvimento das plantas, de produção e de qualidade dos frutos de melão ao longo do ciclo. As plantas tiveram as características de crescimento retardadas e menor desenvolvimento em função do aumento da salinidade da água de irrigação, apresentando redução superior a 20% para a o peso seco da parte aérea, área foliar, número de ramos, comprimento de ramos secundários e 16,7% para o comprimento do ramo principal. Além disso, a salinidade provocou atraso no desenvolvimento dos frutos e redução de 16% no seu peso final, sem modificar significativamente os teores de carboidratos e sólidos solúveis totais. Ao longo do desenvolvimento houve aumento no teor de sólidos solúveis totais dos frutos, especialmente em função do acréscimo de sacarose nos estádios finais de desenvolvimento.

Abstract Background: Salvia urica Epling is taxonomically and phylogenetically related to Salvia amarissima Ortega. The last species has pharmacological relevance by its contents of bioactive metabolites. Nowadays, Salvia urica has no reports about its chemical constituents and pharmacological activities. Hypothesis: Does the close relationship between S. amarissima and S. urica led both species produce similar specialized metabolites? Does Salvia urica display similar pharmacological effects as S. amarissima? Studied species: Salvia urica Epling (Lamiaceae). Study site and dates: The plant material was collected in Teopisca, Chiapas, Mexico, in December 2021. Methods: Metabolites of the acetone extract from Salvia urica were identified by GC-MS and HPLC-PDA profiling. In parallel, a phytochemical study was conducted, and the individual constituents purified, previously characterized by 1D NMR, were assayed on antihyperglycemic effect in diabetic mice and a charcoal-gum arabic-induced hyperperistalsis model in rats. Results: The volatile compounds identified by GC-MS were alkanes, aromatics and triterpenes. The principal constituents of the acetone extract of Salvia urica were amarissinin A and 5,6-dihydroxy-7,3',4'-trimethoxyflavone, which were also quantified by HPLC-PDA. The extract and both metabolites isolated showed an antihyperglycemic effect on streptozotocin-induced diabetic mice, suggesting a possible synergic effect. In addition, the compound 5,6-dihydroxy-7,3',4'-trimethoxyflavone (IC50 = 0.79 mg/kg) showed a better antipropulsive effect than loperamide (IC50 = 16.6 mg/kg). Conclusions: The phytochemical composition of an acetone extract of Salvia urica was determined by first time. The metabolites isolated from this plant support the phylogenetic relationship of S. urica with Salvia amarissima, and they showed antipropulsive and antihyperglycemic effects.

Resumen Antecedentes: Salvia urica Epling está relacionada taxonómica y filogenéticamente con Salvia amarissima Ortega. Ésta última tiene relevancia farmacológica por su contenido de metabolitos secundarios. A la fecha, Salvia urica no cuenta con reportes de sus constituyentes químicos y de sus actividades farmacológicas. Hipótesis: ¿La relación cercana entre S. amarissima y S. urica permite que ambas especies produzcan metabolitos similares de tipo terpenoide? ¿Salvia urica produce un efecto farmacológico similar a S. amarissima? Especies de estudio: Salvia urica Epling (Lamiaceae) Sitio y años de estudio: El material vegetal fue colectado en Teopisca, Chiapas, México, en diciembre de 2021. Métodos: Los constituyentes de las partes aéreas de Salvia urica, se identificaron por medio del perfilamiento por GC-MS y HPLC-PDA. Paralelamente, se realizó un estudio fitoquímico, y los constituyentes individuales, caracterizados por RMN de 1D, se evaluaron en un ensayo de actividad antihiperglucémica y en un modelo de hiperperistalsis. Resultados: Los componentes volátiles identificados por GC-MS son de tipo alcano, aromático y triterpenoide. Los principales constituyentes no volátiles, son amarissinina A y 5,6-dihidroxi-7,3',4'-trimetoxiflavona. Ambos metabolitos se cuantificaron por HPLC-PDA. El extracto de acetona y los dos metabolitos aislados mostraron efecto antihiperglucémico en ratones diabéticos, sugiriendo que hay un posible efecto sinérgico. El compuesto 5,6-dihidroxi-7,3',4'-trimetoxiflavona (IC50 = 0.79 mg/kg) mostró un mejor efecto antipropulsivo que loperamida (IC50 = 16.6 mg/kg). Conclusiones: Se identificaron por primera vez los metabolitos mayoritarios de Salvia urica. Dos de estos metabolitos se aislaron previamente de Salvia amarissima, apoyando su relación filogénetica. Los dos compuestos mostraron efecto antipropulsivo y antihiperlgucémico.

In many South African universities, full research students receive little support during the research conceptualisation stage of the research journey, other than that provided by their supervisors, who tend to have limited time to engage with their students. Furthermore, during the proposal phase, scant attention is paid to the role of writing in research conceptualisation and scholarly development. In an attempt to address this neglect, the authors of this article worked collaboratively with academic staff from two schools within the Faculty of Commerce, Law, and Management at the University of the Witwatersrand to pilot academic literacies-informed projects aimed at integrating writing in the first year of existing postgraduate research programmes. This article provides insight into factors that constrain and enable such an integration endeavour. Data was collected through focus group discussions with the project teams from the participating schools. Drawing on Margaret Archer's structure, culture, and agency as the analytical framework, five themes emerged from the data: leadership and oversight, supervision and postgraduate pedagogy, supervisor awareness and support, the postgraduate research education curriculum, and student engagement and commitment. The authors discuss these themes in terms of their enabling and constraining dimensions, and conclude with observations that could inform similar initiatives in other postgraduate research programmes.

ABSTRACT This study aimed to calibrate and test the SARRA-H (Système d’Analyse Régionale des Risques Agroclimatologiques) crop model for cowpea, as well as conducting a climate risk zoning for this crop in a region located in Eastern Amazon, allowing the identification of locations and sowing dates that favor the production considering both the water deficit and the probability of occurrence of severe rains during the harvest period. The model was calibrated and validated with data from experiments conducted between 2013 and 2016 in the municipality of Castanhal, PA, Brazil. Low climate risk areas were defined as those that had a water requirement satisfaction index (WRSI) greater than or equal to 0.5 in the reproductive phase combined with the occurrence of rainfall below 20 mm at the harvest for, at least, 80% of the years for which planting was simulated. The model was able to simulate the water balance, growth and development of cowpea under the climate and soil conditions of the studied location with high precision and accuracy. The optimal period for sowing cowpea comprises the interval between June 5th and 25th for regions located above 2° S and between March 25th and April 15th for regions below 2º S.

RESUMO Esta pesquisa teve como objetivo calibrar e testar o modelo de cultura SARRA-H (Système d’Analyse Régionale des Risques Agroclimatologiques) para o caupi, bem como realizar o zoneamento de risco climático para esta cultura em uma região localizada na Amazônia Oriental, a fim de permitir a identificação de locais e datas de semeadura que favoreçam a produção considerando tanto o déficit hídrico como a probabilidade de ocorrência de chuvas severas durante o período da colheita. O modelo foi calibrado e validado com dados de experimentos realizados entre 2013 e 2016 no município de Castanhal, PA. As áreas de baixo risco climático foram definidas como aquelas que apresentaram índice de satisfação da necessidade hídrica (WRSI) maior ou igual a 0,5 na fase reprodutiva combinado com a ocorrência de chuvas abaixo de 20 mm na colheita por, pelo menos, 80% dos anos onde foi simulado o plantio. O modelo foi capaz de simular o balanço hídrico, crescimento e desenvolvimento do feijão-caupi nas condições climáticas e de solo da região estudada com boa precisão e exatidão. O período de ótima semeadura para o feijão-caupi compreende o intervalo entre 5 e 25 de junho para regiões localizadas acima de 2° S, e entre 25 de março e 15 de abril para regiões abaixo de 2º S.

ABSTRACT The occurrence of water with high concentrations of salts hinders the expansion of irrigated agriculture in the semi-arid region of the Brazilian Northeast, making it necessary to adopt strategies capable of minimizing the effects of salt stress on plants. In this context, the objective of present study was to evaluate the effects of hydrogen peroxide application on water relations, gas exchange, photosynthetic pigments, and growth of guava cv. Paluma under irrigation with saline waters in the seedling formation stage. A randomized block design was used, in a 5 × 4 factorial scheme, with three replicates, with five levels of electrical conductivity of water - ECw (0.3, 1.3, 2.3, 3.3, and 4.3 dS m-1) and four concentrations of hydrogen peroxide - H2O2 (0, 25, 50, and 75 µM). Irrigation water salinity above 0.3 dS m-1 increased electrolyte leakage in the leaf blade and reduced the relative water content, synthesis of photosynthetic pigments, gas exchange, and growth of seedlings of guava cv. Paluma, at 80 days after sowing. Foliar application of hydrogen peroxide at concentrations of up to 75 µM reduces the relative water content in the leaf blade of guava seedlings and did not mitigate the effects of salt stress on guava plants in the seedling formation stage.

RESUMO A ocorrência de água com elevadas concentrações de sais dificulta a expansão da agricultura irrigada no semiárido do Nordeste brasileiro, tornando-se necessária a adoção de estratégias capazes de minimizar os efeitos do estresse salino sobre as plantas. Neste contexto, objetivou-se avaliar os efeitos da aplicação de peróxido de hidrogênio nas relações hídricas, nas trocas gasosas, nos pigmentos fotossintéticos e no crescimento de goiabeira cv. Paluma sob irrigação com águas salinas na formação de mudas. Foi utilizado o delineamento em blocos casualizados, em esquema fatorial 5 × 4, com três repetições, sendo cinco níveis de condutividade elétrica da água - CEa (0,3; 1,3; 2,3; 3,3 e 4,3 dS m-1) e quatro concentrações de peróxido de hidrogênio - H2O2 (0; 25; 50 e 75 µM). A salinidade da água de irrigação acima de 0,3 dS m-1 aumentou o extravasamento de eletrólitos no limbo foliar, reduziu o conteúdo relativo de água, a síntese de pigmentos fotossintéticos, as trocas gasosas e o crescimento das mudas de goiabeira cv. Paluma, aos 80 dias após a semeadura. A aplicação foliar de peróxido de hidrogênio em concentrações de até 75 µM, reduz o conteúdo relativo de água no limbo foliar de mudas de goiabeira e não ameniza os efeitos do estresse salino em plantas de goiabeira na fase de formação de mudas.

ABSTRACT Combining refrigeration with packaging is a commonly used technique for fruits intended for export. Thus, the objective of this study was to adapt the post-harvest management of biofortified sweet potato cultivars, using packaging and refrigeration, focused on reaching distant export markets while maintaining the commercial quality. Sweet potatoes of the cultivars BRS-Amélia and Beauregard were selected after harvesting, washed, and packaged. The experimental design used was completely randomized, in a 4 × 7 factorial arrangement consisted of 4 treatments (cultivar BRS-Amélia with and without packaging; and cultivar Beauregard with and without packaging) and 7 evaluations under storage conditions: at 0, 7, 14 (under refrigeration at approximately 8 °C), 17, 20, 23, and 26 days (under room temperature conditions at approximately 25 °C). Each experimental unit contained 500 g of tubbers. The results showed that the refrigerated storage combined with packaging extended the shelf life of the evaluated sweet potatoes: 17 days for BRS-Amélia and 26 days for the cultivar Beauregard. The BRS-Amélia cultivar maintained higher firmness, soluble solids and carbohydrate contents, chroma, and antioxidant activity (FRAP method), and total phenolic contents, in both raw and cooked tissues. The cultivar Beauregard presented less dehydration and greater stability in vitamin C, total phenolic, total carotenoid, soluble carbohydrate, and starch contents in raw and cooked potatoes. Therefore, the combination of packaging and refrigeration preserved the commercial quality of biofortified sweet potatoes for export markets.

RESUMO Combinar refrigeração com embalagem é uma técnica comumente utilizada para frutas destinadas à exportação. Assim, o objetivo deste estudo foi adequar o manejo pós-colheita de cultivares de batata-doce biofortificadas, utilizando embalagem e refrigeração, com foco em atingir mercados de exportação distantes e mantendo a qualidade comercial. As batatas-doces das cultivares BRS-Amélia e Beauregard foram selecionadas após a colheita, lavadas e embaladas. O delineamento experimental utilizado foi inteiramente casualizado, em arranjo fatorial 4 × 7 composto por 4 tratamentos (cultivar BRS-Amélia com e sem embalagem; e cultivar Beauregard com e sem embalagem) e 7 avaliações nas condições de armazenamento: aos 0, 7, 14 (sob refrigeração a aproximadamente 8 °C), 17, 20, 23 e 26 dias (sob condições de temperatura ambiente a aproximadamente 25 °C). Cada unidade experimental continha 500 g de tubérculos. Os resultados mostraram que o armazenamento refrigerado aliado à embalagem prolongou a vida útil da batata-doce avaliada: 17 dias para BRS-Amélia e 26 dias para a cultivar Beauregard. A cultivar BRS-Amélia manteve maior firmeza, solúveis sólidos e teor de carboidratos, croma e atividade antioxidante (método FRAP) e teor de fenólicos totais, tanto nos tecidos crus quanto cozidos. A cultivar Beauregard apresentou menor desidratação e maior estabilidade nos teores de vitamina C, fenólicos totais, carotenóides totais, carboidratos solúveis e amido em batatas cruas e cozidas. Portanto, a combinação de embalagem e refrigeração preservou a qualidade comercial da batata-doce biofortificada para os mercados de exportação.