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Carbon export efficiency is a key indicator of the capacity of biological pump, but the controlling mechanism of the efficiency remains unclear. Our findings revealed that interannual variations in seasonal carbon export efficiency are determined by direct factors including riverine nutrient fluxes, stratification, residence time. These direct factors are finally attributed to two indirect factors (human activities and climate change). We quantified the absolute contributions of direct and indirect factors to carbon export efficiency. The results showed that the carbon export efficiency in the northern Gulf of Mexico in spring (summer; autumn; winter) was driven by human activities, which accounted for an absolute contribution of 16.02% (7.20%; 4.00%; 8.49%, respectively) through riverine nutrient fluxes, and by climate change, which accounted for an absolute contribution of 33.51% (21.43%; 25.73%; 15.80%, respectively) through stratification and water residence time. Moreover, carbon export efficiency could be predicted by MEI of 8 months earlier.

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Our objectives were to study characteristics of the fruit (weight, percentage of husk/grain), to determine the concentration and accumulation of nutrients in the fruits, grain and husk, and to verify the existence of genetic diversity in Coffea canephora genotypes. The experiment was conducted with 20 genotypes in a four-year-old plantation, in a randomized block design with four replications and five plants per plot. The fruits were oven-dried, depulped (husk separated from the grain) and sent to a laboratory for nutritional analysis. Macronutrients N and K were the most accumulated/exported in fruits, respectively. In addition, the different genotype control cycles influenced the accumulation of nutrients in the fruits. There was genetic diversity among the 20 C. canephora genotypes, studied for the characteristics of concentration and percentage of grain/straw nutrients in the fruit. Genotypes 2, 8 and 13 were the ones with the greatest genetic distance, consequently they are the most dissimilar when compared to the other genotypes. Genotypes 8 and 1 stand out for having a higher proportion of fruit weight in relation to grains. Therefore, they are the genotypes that need a smaller amount of fruit to produce 1000 kg of ground coffee.

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Flaviviruses have a cytoplasmic replicative cycle, and crucial events, such as genome translation and replication, occur in the endoplasmic reticulum. However, some viral proteins, such as C, NS1, and NS5 from Zika virus (ZIKV) containing nuclear localization signals (NLSs) and nuclear export signals (NESs), are also located in the nucleus of Vero cells. The NS2A, NS3, and NS4A proteins from dengue virus (DENV) have also been reported to be in the nucleus of A549 cells, and our group recently reported that the NS3 protein is also located in the nucleus of Huh7 and C636 cells during DENV infection. However, the NS3 protease-helicase from ZIKV locates in the perinuclear region of infected cells and alters the morphology of the nuclear lamina, a component of the nuclear envelope. Furthermore, ZIKV NS3 has been reported to accumulate on the concave face of altered kidney-shaped nuclei and may be responsible for modifying other elements of the nuclear envelope. However, nuclear localization of NS3 from ZIKV has not been substantially investigated in human host cells. Our group has recently reported that DENV and ZIKV NS3 alter the nuclear pore complex (NPC) by cleaving some nucleoporins. Here, we demonstrate the presence of ZIKV NS3 in the nucleus of Huh7 cells early in infection and in the cytoplasm at later times postinfection. In addition, we found that ZIKV NS3 contains an NLS and a putative NES and uses the classic import (importin-α/ß) and export pathway via CRM-1 to be transported between the cytoplasm and the nucleus. IMPORTANCE Flaviviruses have a cytoplasmic replication cycle, but recent evidence indicates that nuclear elements play a role in their viral replication. Viral proteins, such as NS5 and C, are imported into the nucleus, and blocking their import prevents replication. Because of the importance of the nucleus in viral replication and the role of NS3 in the modification of nuclear components, we investigated whether NS3 can be localized in the nucleus during ZIKV infection. We found that NS3 is imported into the nucleus via the importin pathway and exported to the cytoplasm via CRM-1. The significance of viral protein nuclear import and export and its relationship with infection establishment is highlighted, emphasizing the development of new host-directed antiviral therapeutic strategies.

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The objective of the present study was to describe the total and fragmented external loads, at different intensities, of soccer referees in European and South American competitions during official matches through a systematic review and meta-analysis of cross-sectional studies. A systematic review was conducted in April, 2020. In all, 32 studies were included, incorporating 578 referees evaluated in 3170 games through video analysis or a global positioning system. Regarding external loads, it was observed that the total average distance covered by the referees was 10,461.74 m, with running speeds predominantly below 13 km.h-1. The total distance covered by the referees in the European competitions was higher and more intense than that of the referees in the South American tournaments, being 11,187.02 m and 9319.61 m, respectively. We suggest that referees' training can be organized according to the distances found at different intensities, in which low-intensity races can be performed below 13 km.h-1 with distances of approximately 4500 m, while high-intensity training can be developed with speeds from 18 to 24 km.h-1 for approximately 800 m. In addition, planning must consider the competition characteristics.

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The aim was to evaluate the agronomic and qualitative attributes of early-cycle common bean cultivars with different grains types grains in response to top-dressing nitrogen (N) doses. The experiment was carried out using a randomized block design, in a split-plot scheme, with 4 replicates. The plots consisted of the cultivars IAC Nuance, IAC 1849 Polaco and IAC Veloz, with speckled, Carioca and black grains, respectively. The subplots were formed by N doses applied as top-dressing: 0 kg ha-1, 60 kg ha-1 (applied in the stage of third trifoliate leaf), 120 kg ha-1 (1/2 applied at third trifoliate leaf stage + 1/2 applied at the floral bud stage) and 180 kg ha-1 (1/3 applied at the first trifoliate leaf stage + 1/3 applied at the third trifoliate leaf stage + 1/3 applied at the floral bud stage). IAC Veloz stood out for grain yield, showing the highest grain yield in the lowest N doses, being classified as efficient to the use of N. The cultivars IAC Nuance and IAC 1849 Polaco reached maximum yields with 155 and 163 kg ha-1 of N. The IAC Nuance was the most responsive, increasing grain yield by up to 25.3% due to nitrogen fertilization. Increasing N doses applied as top-dressing increased the sieve yield and crude protein content of the common bean cultivars, with IAC Nuance standing out. The cultivars showed good grain quality, and IAC 1849 Polaco and IAC Veloz had the shortest cooking time and IAC Veloz also had the fastest hydration.

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This research focuses on the moderation effects of Hofstede's cultural dimension that influence the relation between ambidextrous leadership and export performance in Born Global Firms in two countries with different cultural characteristics, Vietnam and Colombia. We collected the data from 800 exporting firms in two countries, Colombia and Vietnam, that are characterised by their having begun international operations in the first three years of being Born Global. The results demonstrate that ambidextrous leadership has a positive impact on export performance. Additionally, the dimensions of uncertainty avoidance and indulgence moderate the relation between ambidextrous leadership and export performance, while long-term orientation does not affect the relationship.

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The shortest dystrophins, Dp71 and Dp40, are transcribed from the DMD gene through an internal promoter located in intron 62. These proteins are the main product of the DMD gene in the nervous system and have been involved in various functions related to cellular differentiation and proliferation as well as other cellular processes. Dp71 mRNA undergoes alternative splicing that results in different Dp71 protein isoforms. The subcellular localization of some of these isoforms in the PC12 cell line has been previously reported, and a differential subcellular distribution was observed, which suggests a particular role for each isoform. With the aim of obtaining information on their function, this study identified factors involved in the nuclear transport of Dp71 and Dp40 isoforms in the PC12 cell line. Cell cultures were treated with specific nuclear import/export inhibitors to determine the Dp71 isoform transport routes. The results showed that all isoforms of Dp71 and Dp40 included in the analysis have the ability to enter the cell nucleus through α/ß importin, and the main route of nuclear export for Dp71 isoforms is through the exportin CRM1, which is not the case for Dp40.

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Scientific works examining coal-derived nanoparticles (NPs) containing potentially toxic elements (PTEs) confined in marine suspended sediments (MSSs) in port regions worldwide is an understudied topic, despite the fact that coal NPs have tremendous negative impacts on marine estuaries. The general objective of this study is to analyze the NP levels of coal, including PTEs, contained within MSSs in the general vicinity of the largest Caribbean port in Colombia. The morphology, size, chemical composition, and agglomeration states of NPs within MSSs of the sampled beaches were calculated through modern electron microscopy. The methodology used to detect chemical elements, unfortunately with EDS, it is not possible to precisely specify the chemical elements of low atomic weight (e.g. H, O, F, etc.) Therefore, with the EDS available today, it is only possible to have an idea of the chemical composition of each detected particle. Thus, it was possible to obtain the average frequency of the chemical elements identified in the 23 analyzed sampling points. Through the results, more than one thousand particles were detected in the most abundant phases, thus, the most frequent particles in the results of this manuscript were described. Sample point 8, located closest to the coal export port, had a higher concentration of nano-toxic elements (Al, Fe, Si, K, Mg, K) most concerning for human health in addition to being harmful to marine life. This study suggests that public policies dealing with MSS pollution need to be discussed by public managers to avoid further and sustained environmental degradation. The need to create projects will subsidize legacy liabilities generated by coal in seaports in other regions of the world.

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In trypanosomatids, transcription is polycistronic and all mRNAs are processed by trans-splicing, with export mediated by noncanonical mechanisms. Although mRNA export is central to gene regulation and expression, few orthologs of proteins involved in mRNA export in higher eukaryotes are detectable in trypanosome genomes, necessitating direct identification of protein components. We previously described conserved mRNA export pathway components in Trypanosoma cruzi, including orthologs of Sub2, a component of the TREX complex, and eIF4AIII (previously Hel45), a core component of the exon junction complex (EJC). Here, we searched for protein interactors of both proteins using cryomilling and mass spectrometry. Significant overlap between TcSub2 and TceIF4AIII-interacting protein cohorts suggests that both proteins associate with similar machinery. We identified several interactions with conserved core components of the EJC and multiple additional complexes, together with proteins specific to trypanosomatids. Additional immunoisolations of kinetoplastid-specific proteins both validated and extended the superinteractome, which is capable of supporting RNA processing from splicing through to nuclear export and cytoplasmic events. We also suggest that only proteomics is powerful enough to uncover the high connectivity between multiple aspects of mRNA metabolism and to uncover kinetoplastid-specific components that create a unique amalgam to support trypanosome mRNA maturation.

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Ecuador is one of the largest banana exporters in the world. This sector generates wealth and employment in the country. Life cycle method tools support finding critical points and improvement measures in systems. In this study, the Ecuadorian banana is evaluated through life cycle assessment (LCA), including agriculture, packaging, transfer to the Port of Guayaquil, and transport to a foreign port. OpenLCA software was used, applying the Recipe Midpoint (H) V1.13 impact evaluation method and using primary data collected from a local producer and secondary data from Ecoinvent 3.6 databases, Agribalyse 3.0.1, and the literature. Functional units were established at three levels: "1 ton of Banana at-the-farm-gate"; "1 ton of Banana at-the-packaging-stage-gate"; and "1 ton of Banana at-the-port-of-destination". The impact categories evaluated are climate change (GWP100), fossil depletion (FDP), freshwater eutrophication (FEP), marine eutrophication (MEP), ozone layer depletion (ODPinf), particulate matter formation (PMFP), formation of photochemical oxidants (POFP), and terrestrial acidification (TAP100). The carbon footprint (GWP100) of "Banana at-the-farm-gate", "Banana at-the-packaging-stage-gate", and "Banana at-the-foreign-port" ranged from 194 to 220, 342 to 352, and 615.41 to 625.44 kg CO2-Eq/Ton banana, respectively. Hotspots of the system are the fertilizer field emissions, cardboard packaging, rachis disposal, and maritime transport. Improvement measures should focus on reducing the amount of fertilizers and developing circular alternatives for residual biomass valorization.

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Nutrient discharge into rivers and estuaries and the factors that control it need to be further understood to decrease the risk of harmful algae blooms on these ecosystems. Preliminary seasonal physicochemical parameters at six stations along the Negro River Estuary (Argentina) were studied during 2019 (Austral summer, winter, and spring) with high- and low-frequency data. Three of the stations were mainly estuarine-influenced and three were marine-influenced ones. The concentration of phosphate (P), river discharge, meteorological conditions, seasonality, and physicochemical variables were analyzed. Total phosphorus (TP) showed seasonal variations and was higher than previously reported for the upper watershed in all stations in the warmer months, except for the marine control one. Orthophosphate values were also high compared to previous watershed data and changed independently of TP fluctuations. Changing turbidity, water temperature, pH, and conductivity did not appear to have an essential role in phosphorus variations. An unexplained high TP spike in the late spring sample shows the need for further research in the area, while the seawater mixing with P-rich river water could be acting as a dilution agent at the mouth of the river.

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Analisamos comparativamente informes demográficos de qualidade aceitável acerca dos escravizados nascidos na África para Minas Gerais, São Paulo e Maranhão de 1804 a 1848. As parcelas dos nascidos na África em relação aos escravizados e às razões de sexo de todos os cativos, de acordo com as idades, auxiliaram-nos a remontar a dinâmica retrospectiva da chegada dos africanos às regiões. Supondo certas hipóteses e procedimentos, a partir das coortes etárias, estimamos as proporções de africanos e as razões de sexo da população cativa para os períodos anteriores aos das listas nominativas de habitantes. A dinâmica retrospectiva da introdução de africanos reconstruída mostrou-se bastante correlacionada à história econômica das diferentes regiões estudadas.

We compare the surviving enslaved people present in demographic censuses of acceptable quality for Minas Gerais, São Paulo and Maranhão from 1804 to 1848. The share of those born in Africa in relation to slaves and the sex ratio of all captives according to their ages helped us find the retrospective dynamics of the arrival of Africans to these regions. When using age cohorts, we estimate, assuming certain hypotheses and procedures, the proportions of Africans and the sex ratios of the captive population for periods prior to those of the nominative lists of inhabitants. The retrospective dynamics of the reconstructed introduction of these Africans proved to be closely correlated with the economic history of the different regions analyzed.

Analizamos comparativamente a los sobrevivientes esclavizados presentes en los informes demográficos evaluados como de calidad aceptable para Minas Gerais, São Paulo y Maranhão entre 1804 y 1848. La proporción de los nacidos en África en relación con los esclavizados y la proporción de sexos de todos los cautivos, según las edades, nos ayudaron a trazar la dinámica retrospectiva de la llegada de africanos a estas regiones. Utilizando las cohortes de edad, estimamos, asumiendo ciertas hipótesis y procedimientos, las proporciones de africanos y las proporciones de sexos de la población cautiva para períodos anteriores a las listas nominativas de habitantes. La dinámica retrospectiva de la introducción reconstruida de africanos demostró estar altamente correlacionada con la historia económica de las diferentes regiones estudiadas.

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El Perú se considera un país potencia en cuanto a la exportación textil de la alpaca, cuya fibra natural es muy fina, ligera y con alto valor a nivel mundial. Para el año 2019, la exportación total de fibra de alpaca en Perú llegó a un total de 23 países, incluyendo mercados en Europa, Asia y Norteamérica. La tendencia en el comercio exterior incluyendo las empresas textiles de alpaca, se ha dirigido a garantizar el cuidado del medio ambiente y la inocuidad de los productos respecto a la salud humana. Se realizó un estudio desde el paradigma post-positivista, con enfoque cualitativo y el método hermenéutico, para interpretar la situación de exportación y sanitación internacional en empresas peruanas productoras de prendas de alpaca en Huancayo y Lima. Se obtuvo información a partir de cuatro informantes voluntarios de cada empresa acerca de aspectos relacionados con exportación de las prendas de alpaca: competitividad, promoción, proveedores, producción, calidad de producto, valor agregado, calidad de servicio, mercados destino, demanda y herramientas de inteligencia comercial, entre otros. Asimismo, se indagó sobre la concepción y cumplimiento del Reglamento Sanitario Internacional. Las empresas evaluadas, emplean excelente materia prima, garantizan un control de calidad de sus productos ofreciendo textiles competitivos que se distribuyen en diversos mercados internacionales, emplean herramientas de comercialización que favorecen la identificación de regulaciones arancelarias y la capacitación de su personal. No obstante, muestran carencias en el cumplimiento del RSI, requiriendo adoptar medidas que garanticen la salud pública al comercializar sus productos(AU)

Peru is considered a powerful country in terms of alpaca textile exports, whose natural fiber is very fine, light and highly valued worldwide. For the year 2019, the total export of alpaca fiber in Peru reached a total of 23 countries, including markets in Europe, Asia and North America. The trend in foreign trade, including alpaca textile companies, has been aimed at guaranteeing care for the environment and the safety of products with respect to human health. A study was carried out from the post-positivist paradigm, with a qualitative approach and the hermeneutical method, to interpret the export situation and international sanitation in Peruvian companies that produce alpaca garments in Huancayo and Lima. Information was obtained from four volunteer informants from each company about aspects related to the export of alpaca garments: competitiveness, promotion, suppliers, production, product quality, added value, service quality, destination markets, demand and marketing tools. commercial intelligence, among others. Likewise, the conception and compliance with the International Health Regulations were inquired about. The evaluated companies use excellent raw material, guarantee quality control of their products by offering competitive textiles that are distributed in various international markets, use marketing tools that favor the identification of tariff regulations and the training of their personnel. However, they show deficiencies in compliance with the RSI, requiring the adoption of measures that guarantee public health when marketing their products(AU)

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Background: Penile fracture is a pathology of young cattle that perform precocious and disordered breeding. The incompatibility of height between males and females and sodomy between males cause a great pressure on the sigmoid flexure and retractor muscle of the penis, which are the main causes and sites of organ injury. This study aimed to describe the epidemiological and pathological aspects of penile fractures observed in young bulls raised in pre-export feedlots (PEFs) in southern Brazil. Cases: In 2 PEFs located in the municipalities of Pelotas (property 1) and Capão do Leão (property 2), 3 male cattle [1 from property 1 and 2 from property 2] presented subcutaneous edema in the foreskin and perineum, associated with dysuria. The evolution of the clinical picture was approximately 20 days in all cases, with evolution to death. The bovine necropsied on property 1 had an increased volume and inguinal edema, involving the penis and scrotal sac. Necrosis of the subcutaneous tissue and local musculature was also observed. The testicles were surrounded by the necrotic tissue, and the right testis was swollen, with flaccid parenchyma adhering to the tunica albuginea. In the necropsy of 1 bull from property 2, an increase in the inguinal volume was observed, with an extensive area of necrosis and edema extending from the prepuce to the caudal musculature of the scrotal sac. There were also marked varicosis in the sigmoid flexure and necrosis of the adjacent region, without the involvement of the corpus cavernosum. During the necropsy of the 2 young bulls, fragments of organs from the abdominal, thoracic, and brain cavities were collected and fixed in 10% buffered formalin. From the bull of the property 2, an anatomical piece consisting of the penis, prepuce, and testicles was also collected and fixed in 10% buffered formalin. After 48 h, the tissue samples were cleaved, embedded in paraffin, cut into 3-µm-thick sections, and stained using hematoxylin and eosin (HE). A histological evaluation of the penile lesions in both cattle revealed intense hemorrhage, congestion, and necrosis of the muscles and tissues adjacent to the corpus cavernosum. In addition to areas of dystrophic calcification, neutrophil and macrophage infiltration was also observed. In the bull from the property 1, an intense edema and proliferation of fibrous tissue surrounding the urethra were noted. There were also marked tubular degeneration and intense infiltration of neutrophils, lymphocytes, and macrophages in the inner portion of the tunica albuginea. Discussion: In the present cases, the diagnosis was based on epidemiological data associated with clinical signs and pathology. The macroscopic lesions observed were probably due to the involvement of blood vessels adjacent to the penis, which suffered trauma during sodomy mating among cattle. These lesions have been described in other reports of this pathology and in diseases, such as acropostitis-phimosis, fibropapilloma of the glans, preputial abscess, and urolithiasis, and the differential diagnosis of these diseases must be carried out, as they have different etiologies. In the bulls of the present study, no lesions were observed in the corpus cavernosum, and this condition was attributed to the presence of varicosis and accumulation of urine in the prepuce, due to the difficulty in exposing the penis. Histologically, there were intense hemorrhage, congestion, and necrosis of the muscles and tissues adjacent to the corpus cavernosum, with the infiltration of neutrophils and macrophages, and areas of dystrophic calcification. The presence of necrotic lesions in tissues adjacent to the penis may be related to hypoxia, vascular lesions, or the action of chemical elements present in the urine. In both cases, vascular lesions were present, which were attributed to the main triggering factor for the disease.

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The article considers econometric ridge regression models of the risk-sensitive sunflower yield on the example of an export-oriented agricultural crop. In particular, we have proved that despite the functional mulcollinearity of the predictors in the sunflower yield model with respect to risk caused by the algorithm peculiarities of the hierarchy analysis methods, the ridge regression procedure makes it possible to obtain its complete specification and provide biased but stable estimates of the forecast parameters in the case of uncertain input variables. It has been substantiated that the rational value of the displacement parameters is expedient to be established using a graphical interpretation of the ridge wake as the border of fast and slow fluctuations in the estimates of the ridge regression coefficients. Econometric models were calculated using SPSS Statistics, Mathcad and FAR-AREA 4.0 software. The empirical basis for forecast calculations was the assessment of trends in sunflower production in all categories of farms in the Rostov region of Russia for the period of 2008-2018. The calculation results of econometric models made it possible to develop three author's scenarios for the sunflower production in the region, namely, inertial, moderate, and optimistic ones that consider the export-oriented strategy of the agro-industrial complex.(AU)

O artigo considera modelos econométricos de regressão de rendimento de girassol sensível ao risco sobre o exemplo de uma cultura agrícola orientada para a exportação. Em particular, provamos que apesar da multicolinearidade funcional dos preditores no modelo de rendimento de girassol com relação ao risco causado pelas peculiaridades dos algoritmos dos métodos de análise hierárquica, o procedimento de regressão de cristas permite obter sua especificação completa e fornecer estimativas tendenciosas, mas estáveis dos parâmetros de previsão no caso de variáveis de entrada incertas. Foi comprovado que o valor racional dos parâmetros de deslocamento é conveniente de ser estabelecido usando uma interpretação gráfica da esteira da crista como fronteira das flutuações rápidas e lentas nas estimativas dos coeficientes de regressão da crista. Os modelos econométricos foram calculados usando o software SPSS Statistics, Mathcad e FAR-AREA 4.0. A base empírica para os cálculos de previsão foi a avaliação das tendências da produção de girassol em todas as categorias de fazendas na região de Rostov na Rússia para o período de 2008-2018. Os resultados dos cálculos dos modelos econométricos permitiram desenvolver três cenários de autor para a produção de girassol na região, a saber, os cenários inercial, moderado e otimista que consideram a estratégia orientada à exportação do complexo agroindustrial.(AU)

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Resumen Introducción. En el municipio de El Peñol, Antioquia, la incursión de pequeños y medianos productores al mercado agroexportador de la gulupa (Passifflora edulis Sims) es hoy una realidad reconocida, que, asumida como caso de estudio, permite aportar a la comprensión de un fenómeno particular: el tránsito de agricultores tradicionales-locales hacia la producción para el mercado internacional, asunto sobre del que versa el presente estudio. Objetivo. Identificar y analizar las causas y consecuencias de la incursión de pequeños y medianos productores de El Peñol, Antioquia, al mercado agroexportador de la gulupa. Materiales y métodos. La investigación, de índole cualitativa, se centró en analizar las múltiples narrativas expuestas por los propios actores localmente asociados al cultivo de gulupa sobre las causas y consecuencias del fenómeno estudiado. La información se recolectó mediante entrevistas a profundidad, posteriormente analizadas en su contenido. Resultados. Entre las causas de la incursión al mercado global destacan las ventajas ofrecidas por el cultivo ante la inestabilidad de los precios de los productos tradicionales, el conocimiento previo de la especie y la oportunidad de tránsito hacia una agricultura más limpia. Entre las consecuencias, el mejoramiento de las condiciones socioeconómicas familiares, la reafirmación de la vocación agrícola de pequeños y medianos productores y la alta dependencia de la intermediación realizada por las empresas agroexportadoras. Conclusiones. Las causas y consecuencias del cambio productivo presentan un carácter multidimensional y ambivalente, situación que induce a explorar el fenómeno más allá de su dimensión económica, dando cuenta, simultáneamente, de sus bondades y riesgos.

Abstract Introduction. In the municipality of El Peñol, Antioquia, the incursion of small and medium producers to the agricultural export market of gulupa (Passifflora edulis Sims) is currently a recognized reality. Subject which, assumed as a case study, contributes to the understanding of a particular phenomenon: the movement of traditional-local farmers towards production for the international market, an issue addressed by this research. Objective. Identify and analyze the causes and consequences of the incursion of small and medium producers from El Peñol, Antioquia, to the agricultural export market of the gulupa. Materials and methods. The research was qualitative and focused on analyzing the multiple narratives presented by the local actors, associated with the gulupa crops about the causes and consequences of the phenomenon studied. The information was collected through in-depth interviews, subsequently analyzing its content. Results. Among the causes of the global market incursion, the advantages offered by the crop are highlighted due to the instability of the prices of traditional products, the prior knowledge of the gulupa and the opportunity to move towards a cleaner agriculture. Among the consequences are the improvement of family socioeconomic conditions, the reaffirmation of the agricultural vocation of small and medium producers and the high dependence on intermediation carried out by agro-exporting companies. Conclusions. The causes and consequences of productive change have a multidimensional and ambivalent character, a situation that leads to explore the phenomenon beyond its economic dimension, while simultaneously presenting simultaneously its benefits and risks.

Resumo Introdução. No município de El Peñol, Antioquia, a incursão de pequenos e médios produtores no mercado agrícola de exportação da gulupa (Passifflora edulis Sims) é uma realidade hoje reconhecida, que, assumida como estudo de caso, permite contribuir para a compreensão de um fenômeno particular: o trânsito de agricultores tradicionais locais para a produção para o mercado internacional, assunto sobre o qual o estudo trata. Objetivo. Identificar e analisar as causas e consequências da incursão de pequenos e médios produtores de El Peñol, Antioquia, no mercado de exportação agrícola da gulupa. Materiais e métodos. A pesquisa, de ordem qualitativa, teve como objetivo analisar as múltiplas narrativas apresentadas pelos próprios atores associados ao cultivo da gulupa sobre as causas e consequências do fenômeno estudado. As informações foram coletadas por meio de entrevistas em profundidade, posteriormente analisadas em seu conteúdo. Resultados. Entre as causas da incursão no mercado global, destacam-se as vantagens oferecidas pela gulupa, dada a instabilidade dos preços dos produtos tradicionais, o conhecimento prévio da espécie e a oportunidade de avançar para uma agricultura mais limpa. Entre as consequências, estão a melhoria das condições socioeconômicas da família, a reafirmação da vocação agrícola dos pequenos e médios produtores e a alta dependência de intermediação realizada pelas empresas agroexportadoras. Conclusões. As causas e consequências da mudança produtiva têm um caráter multidimensional e ambivalente, situação que leva a explorar o fenômeno além de sua dimensão econômica, percebido, ao mesmo tempo, seus benefícios e riscos.

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A significant contributor to water pollution is increased nutrient concentration that results in eutrophication. Modeling approaches are crucial to understanding the dynamics of nutrients in river basins. This study integrates empirical models into Geographic Information Systems to quantify total nitrogen and phosphorus (TN and TP) load and concentration in watercourses of Brazil's Lobo Stream Hydrographic Basin (LSHB). Land use, topographic, demographic, and hydrological data were used to simulate the load and concentration of nutrients generated by point and nonpoint pollution sources. The results indicate that the simulated TN and TP load is primarily generated by nonpoint sources, 81% and 76%, respectively. The Itaqueri River subbasin is the most critical, yielding more than half of the basin's TN and TP load. About 90% of annual LSHB point pollution load is generated in the Itaqueri River subbasin, principally from the Água Branca Stream. The linear regression between simulated and observed concentration indicates significant relationships (TN, r2 = 0.73 (p < 0.05), TP, r2 = 0.78 (p < 0.05)). The method used was able to simulate TN and TP concentration in watercourses, but was inconsistent for point pollution, indicating it represents the dynamics of nutrients in rural basins more effectively than in urban ones. The study shows that its methodology, despite limitations, enables scientists and managers to understand and predict spatial distribution of nutrient concentration in LSHB watercourses.

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Post-transcriptional gene silencing mediated by microRNAs (miRNAs) modulates numerous developmental and stress response pathways. For the last two decades, HASTY (HST), the ortholog of human EXPORTIN 5, was considered to be a candidate protein that exports plant miRNAs from the nucleus to the cytoplasm. Here, we report that HST functions in the miRNA pathway independent of its cargo-exporting activity in Arabidopsis. We found that Arabidopsis mutants with impaired HST shuttling exhibit normal subcellular distribution of miRNAs. Interestingly, protein-protein interaction and microscopy assays showed that HST directly interacts with the microprocessor core component DCL1 through its N-terminal domain. Moreover, mass spectrometry analysis revealed that HST also interacts independently of its N-terminal domain with the mediator complex subunit MED37. Further experiments revealed that HST could act as a scaffold to facilitate the recruitment of DCL1 to genomic MIRNA loci by stabilizing the DCL1-MED37 complex, which in turn promotes the transcription and proper processing of primary miRNA transcripts (pri-miRNAs). Taken together, these results suggest that HST is likely associated with the formation of the miRNA biogenesis complex at MIRNA genes, promoting the transcription and processing of pri-miRNAs rather than the direct export of processed miRNAs from the nucleus.

Assuntos

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BACKGROUND: The Werner syndrome protein (WRN) belongs to the RecQ family of helicases and its loss of function results in the premature aging disease Werner syndrome (WS). We previously demonstrated that an early cellular change induced by WRN depletion is a posttranscriptional decrease in the levels of enzymes involved in metabolic pathways that control macromolecular synthesis and protect from oxidative stress. This metabolic shift is tolerated by normal cells but causes mitochondria dysfunction and acute oxidative stress in rapidly growing cancer cells, thereby suppressing their proliferation. RESULTS: To identify the mechanism underlying this metabolic shift, we examined global protein synthesis and mRNA nucleocytoplasmic distribution after WRN knockdown. We determined that WRN depletion in HeLa cells attenuates global protein synthesis without affecting the level of key components of the mRNA export machinery. We further observed that WRN depletion affects the nuclear export of mRNAs and demonstrated that WRN interacts with mRNA and the Nuclear RNA Export Factor 1 (NXF1). CONCLUSIONS: Our findings suggest that WRN influences the export of mRNAs from the nucleus through its interaction with the NXF1 export receptor thereby affecting cellular proteostasis. In summary, we identified a new partner and a novel function of WRN, which is especially important for the proliferation of cancer cells.

Assuntos

RESUMO

The estrogen receptor alpha (ERα) is a ligand-activated transcription factor whose activity is modulated by its interaction with multiple protein complexes. In this work, we have identified the protein interferon alpha inducible protein 27 (IFI27/ISG12) as a novel ERα-associated protein. IFI27/ISG12 transcription is regulated by interferon and estradiol and its overexpression is associated to reduced overall survival in ER+ breast cancer patients but its function in mammary gland tissue remains elusive. In this study we showed that overexpression of IFI27/ISG12 in breast cancer cells attenuates ERα transactivation activity and the expression of ERα-dependent genes. Our results demonstrated that IFI27/ISG12 overexpression in MCF-7 cells reduced their proliferation rate in 2-D and 3-D cell culture assays and impaired their ability to migrate in a wound-healing assay. We show that IFI27/ISG12 downregulation of ERα transactivation activity is mediated by its ability to facilitate the interaction between ERα and CRM1/XPO1 that mediates the nuclear export of large macromolecules to the cytoplasm. IFI27/ISG12 overexpression was shown to impair the estradiol-dependent proliferation and tamoxifen-induced apoptosis in breast cancer cells. Our results suggest that IFI27/ISG12 may be an important factor in regulating ERα activity in breast cancer cells by modifying its nuclear versus cytoplasmic protein levels. We propose that IFI27/ISG12 may be a potential target of future strategies to control the growth and proliferation of ERα-positive breast cancer tumors.

Assuntos