Resumo Objetivo: O propósito desta pesquisa é explorar como a manutenção do relacionamento com prestadores de serviço durante a pandemia da Covid-19 afeta o bem-estar do consumidor e sua intenção de compra no período pós-pandemia. Originalidade/valor: Este artigo usa dados empíricos coletados durante a pandemia de Covid-19, para compreender como indivíduos podem melhorar seu bem-estar durante eventos estressantes por meio do uso de serviços e também como empresas podem aumentar suas possibilidades de recuperação durante essa situação. Design/metodologia/abordagem: Dados foram coletados através de questionário no Brasil durante o período intermediário da pandemia de Covid-19. Para executar a análise, foram feitas modelagens de equações estruturais. Resultados: Resultados mostram que quanto mais forte era a confiança no prestador de serviço antes do período estressante, maior será a manutenção do relacionamento com ele durante esse período. A manutenção do relacionamento entre consumidor e prestador de serviços durante a pandemia de Covid-19 melhora a satisfação com a vida e a saúde (i.e., bem-estar) do indivíduo (mesmo quando o serviço não é prestado da forma combinada previamente, e.g., aulas on-line de yoga). Os efeitos positivos no bem-estar são explicados por uma maior percepção de controle e sensação de estar ajudando o prestador de serviço durante um período de crise. Adicionalmente, a manutenção do relacionamento com o prestador de serviços durante esse período aumenta a intenção de recompra futura (i.e., após a pandemia) do consumidor junto a esse prestador de serviços.

Abstract Purpose: This research aims to explore how the maintenance of customers’ relations with service providers during the Covid-19 pandemic affects customers’ well-being and repurchase intentions for the post-pandemic period. Originality/value: This paper uses empirical data collected during the Covid-19 pandemic to shed light on how individuals can improve their well-being during stressful life events through service provisions and how businesses can increase chances of recovery after stressful situations such as a pandemic. Design/methodology/approach: Data were collected during the pandemic with Brazilian consumers. Structural equations models (SEM) techniques were used. Findings: Results show that the stronger the customer’s trust in the service provider before the stressful event, the higher the maintenance of the provider’s relationship during this period. More importantly, this relationship maintenance with the service provider during the Covid-19 pandemic (even when the service is not being provided as previously agreed, e.g., online yoga classes) improved the individual’s satisfaction with life and health (i.e., well-being). These positive effects on well-being are explained by perceptions of control and the feeling of helping the service provider during a crisis (i.e., a pandemic). Furthermore, maintaining the relationship with the service provider during this period increased customers’ future repurchase intentions with the business.

The optimized analytical methodology described herein is based on an ion exchange column and an H3PO4 solution (pH 2.24) as the mobile phase, with a flow rate of 0.4 mL min-1 and refractive index detection (RID). On applying the methodology, it was possible to identify 7 products obtained from the oxidation of glycerol with an analysis time of 27 min. The developed method was validated through the evaluation of a series of analytical parameters. The results obtained were evaluated considering the peak area and peak height. The analytical curves showed a correlation coefficient of ≥ 0.986. The coefficient of variation values obtained were ≤ 3.60% for instrumental precision, ≤ 19.36% for intermediate precision in LOQ (1.25 µg mL-1) and ≤ 17.93% for repeatability in LOQ (1.25 µg mL-1) and different days. The limit of quantification established for all compounds was 1.25 µg mL-1 obtained through the parameters of the analytical curve. The accuracy of the method showed recovery values of 85.6 to 112.3% for real fortified sample at 3 concentration levels. Two different samples of glycerol oxidation products were applied to the validated methodology; one obtained from AuNP/SiO2 as catalyst (conversion of 62.42%), and other using AuNP/MWCNT (conversion of 89.5%).

Abstract: Authentication of cell lines is of paramount importance to validate the results from their use in biomedical research. Although isoenzyme polymorphism is the standard method, molecular methods based on mitochondrial DNA (mtDNA) have been developed to replace it. The aim of this study was the improvement of our isoenzyme electrophoretic analysis and the validation of one molecular technique targeted at mtDNA for the authentication of our animal cell lines. The combined method of cellular lysing through osmotic shock, followed by freezing-thawing in N2 to obtain isoenzyme extracts, and with 42 × 106 cells maintained the best efficiency. The superior electrophoretic conditions were PAGE run at 200 V. All cell lines had isoenzymatic mobility corresponding to their species to lactate dehydrogenase, malate-dehydrogenase, and glucose-6-phosphate dehydrogenase isoenzymes, and could be distinguished from each other. Two molecular techniques based on mtDNA were tested, one on the cytochrome b gene and other on cytochrome c oxidase I subunit gene. Due to difficulties in distinguishing all cell lines using only one these techniques, we merged the primers of two methods in such a way that there was a sufficient differentiation of all DNA fragments. The sequencing of these PCR products was also performed to validate these data.

Abstract The constant demand for new antibiotic drugs has driven efforts by the scientific community to prospect for peptides with a broad spectrum of action. In this context, antimicrobial peptides (AMPs) have acquired great scientific importance in recent years due to their ability to possess antimicrobial and immunomodulatory activity. In the last two decades, plants have attracted the interest of the scientific community and industry as regards their potential as biofactories of heterologous proteins. One of the most promising approaches is the use of viral vectors to maximize the transient expression of drugs in the leaves of the plant Nicotiana benthamiana. Recently, the MagnifectionTM expression system was launched. This sophisticated commercial platform allows the assembly of the viral particle in leaf cells and the systemic spread of heterologous protein biosynthesis in green tissues caused by Agrobacterium tumefaciens “gene delivery method”. The system also presents increased gene expression levels mediated by potent viral expression machinery. These characteristics allow the mass recovery of heterologous proteins in the leaves of N. benthamiana in 8 to 10 days. This system was highly efficient for the synthesis of different classes of pharmacological proteins and contains enormous potential for the rapid and abundant biosynthesis of AMPs.

ABSTRACT Enzymatically crossliked gelatin hydrogel was submitted to two different drying methods: air drying and freeze drying. The resulting polymeric tridimensional arrangement (compact or porous, respectively) led to different thermal and swelling properties. Significant differences (p < 0.05) on thermal and mechanical characteristics as well as swelling in non-enzymatic gastric and intestinal simulated fluids (37 ºC) were detected. Water absorption data in such media was modelled according to Higuchi, Korsmeyer-Peppas, and Peppas-Sahlin equations. Freeze dried hydrogel showed Fickian diffusion behavior while air dried hydrogels presented poor adjustment to Higuchi model suggesting the importance of the relaxation mechanism at the beginning of swelling process. It was possible to conclude that the same gelatin hydrogel may be suitable to different applications depending on the drying process used.

Atividades de cultivo de camarão tendem a aumentar a taxa de sedimentação de matéria orgânica nos corpos hídricos receptores de seus efluentes, devido à excessiva produção de produtos de excreção e sobras de ração. Dependendo das condições ambientais, o sistema pode não apresentar condições de autodepuração, gerando um grande acúmulo de nutrientes ao longo da camada sedimentar e intensificação do metabolismo bêntico levando, muitas vezes, o ambiente a um processo de eutrofização e possível situação de anoxia. Utilizaram-se, no presente estudo, incubações in situ com câmaras bentônicas transparentes e opacas, para avaliar o metabolismo bêntico em uma área de cultivo de camarão no estuário da Lagoa dos Patos, RS. Ficou evidente a existência de uma clara interferência do cultivo nos processos de regeneração bêntica de nutrientes, incrementando os fluxos de nitrogênio (na forma de amônio) e fósforo (fosfato). Embora a interferência desta atividade se tenha mostrado de abrangência local e temporária (apenas 4 a 5 meses do ano), é conveniente salientar que ela ganha maior importância em locais rasos e de circulação restrita, como é o caso de baías e enseadas, locais em que o cultivo de camarão é desenvolvido no estuário da Lagoa dos Patos.

Shrimp farming activities tend to increase the organic matter sedimentation rate, by extreme inputs of excreta products and shrimp food (commercial shrimp diet) into the environment. In certain environmental conditions, the auto-depuration system can be surpassed, generating a high production of nutrients at the sedimentary layer as a result of benthic metabolism intensification. Consequently the system can be induced to a eutrophication processes and anoxia. In the present study, in situ incubations with transparent and opaque chambers have been used to evaluate the benthic metabolism in semi-intensive shrimp farming areas in the Patos Lagoon Estuary (pen enclosures). Existence of clear interference of the cultivation in the processes of benthic regeneration of nutrients was evident, resulting in increases of phosphorus (phosphate) and nitrogen (in the ammonium form) fluxes. Even considering that this activity has a local and temporary distribution (only 4 to 5 months of the year), it is important to call attention to the sediment oxygen consumption and the input of nutrients deriving from the regeneration of organic matter, which is enhanced in shallow waters and restricted circulation areas (such as small bays), locations where shrimp cultivation is developed in the Patos Lagoon Estuary.

Objetivou-se com este trabalho verificar a quebra de dormência, utilizando ácido sulfúrico (H2SO4) e escarificação mecânica, e o efeito da luz na germinação das espécies Euphorbia heterophylla, Ipomoea nil, Sida glaziovii e Brachiaria plantaginea. Para avaliar a germinação, os tratamentos foram realizados no escuro e no claro. Não foram constatadas diferenças entre eles nas condições avaliadas, indicando que as espécies em estudo germinam em ambiente com diferentes luminosidades. Quanto a quebra de dormência, observou-se que o tratamento submetido à quebra de dormência aumentou a porcentagem de germinação em algumas espécies. Desse modo, concluiu-se que a quebra de dormência viabiliza condições para germinação de algumas espécies de plantas daninhas e, sob qualquer condição de luminosidade, há germinação das sementes das espécies estudadas.

This research evaluated dormancy break using sulfuric acid (H2SO4), mechanical scarification and the effect of light on the seed germination rate of Euphorbia heterophylla, Ipomoea nil, Sida glaziovii and Brachiaria plantaginea. To evaluate the germination rate, treatments were performed in the dark and light; no differences were observed between both treatments under these conditions, indicating that these species germinate under different light conditions. Dormancy break increases the percentage of germination rate in some species. Thus, dormancy break makes the germination of some species viable. The germination can occur both under light or dark conditions.

Nas áreas de colheita de cana-de-açúcar sem queima prévia (cana-crua), a presença da palha afeta a germinação de plantas daninhas e a dinâmica dos herbicidas. O presente trabalho foi conduzido com o objetivo de avaliar os efeitos do sulfentrazone e imazapic, associado à palha de cana-de-açúcar, com chuva após a aplicação dos herbicidas, no controle de Cyperus rotundus. O delineamento experimental adotado foi o de blocos casualizados no esquema fatorial 3 x 3 x 2 x 2, com quatro repetições, totalizando 144 parcelas. Os tratamentos foram conseqüência da combinação fatorial entre três níveis do fator palha de cana-de-açúcar (20, 10 t ha-1 e ausência de cobertura morta sobre o solo); três níveis do fator herbicida (sulfentrazone a 800 g ha-1, imazapic a 147 g ha-1 e ausência de herbicida); dois níveis do fator intensidade de chuva (10 e 20 mm); e dois níveis do fator épocas em que foram simuladas as chuvas após a aplicação dos herbicidas (24 e 168 horas). Avaliou-se o número de plantas por vaso, a massa seca da parte aérea e das estruturas do sistema subterrâneo e o número de tubérculos e bulbos sadios. Constatou-se que, no caso do herbicida sulfentrazone, a presença de 20 t ha-1 de palha de cana-de-açúcar diminuiu-lhe a eficácia. O herbicida imazapic teve bom desempenho tanto na ausência quanto na presença de palha e causou redução das variáveis estudadas, independentemente da intensidade de chuva. A intensidade de chuva de 10 mm não foi suficiente para transpor o herbicida sulfentrazone na quantidade de 20 t ha-1 de palha. Já a intensidade de 20 mm foi suficiente para lixiviar o herbicida até mesmo na maior quantidade de palha. O herbicida sulfentrazone suportou mais a permanência na palha, pois apresentou melhor eficácia em relação ao imazapic, quando a chuva foi simulada 168 horas após a aplicação dos herbicidas.

In the raw sugarcane harvest areas, straw affects weed germination and herbicide dynamics. Thus, this work was developed to evaluate the effects of applying sulfentrazone and imazapic, associated with sugarcane straw and simulated rain for Cyperus rotundus control. The experiment was arranged in a randomized block design in a 3 x 3 x 2 x 2 factorial scheme with four repetitions, totaling 144 plots. The treatments were the result of a factorial combination of three levels of the factor sugarcane straw (20, 10 t ha-1 and no dead cover on the soil); three levels of the factor herbicide (sulfentrazone at 800 g ha-1, imazapic at 147 g ha-1 and no herbicide); two levels of the factor intensity of rainfall (10 and 20 mm); and two levels of the factor simulated rain after herbicide application (24 and 168 hours). Number of plants per pot, dry mass of the aerial parts and underground system structures, and number of healthy tubers and bulbs were evaluated. Based on the results obtained, it was concluded that the presence of 20 t ha-1 of sugar cane straw reduced the efficacy of the herbicide sulfentrazone while the herbicide imazapic had a good performance with and without straw, causing a reduction in the varieties studied regardless of intensity of the rain. Rain intensity of 10 mm, was not sufficient to surpass the herbicide sulfentrazone in the amount of 20 t ha-1 of straw. However, 20 mm rain intensity was sufficient to cause herbicide leaching even at the largest amount of straw. The herbicide sulfentrazone showed a good resistance to straw since it was more efficacious than imazapic, when rain was simulated 168 hours after the application of the herbicides