Abstract The use of wood is often indicated as a decarbonization strategy for the construction sector. However, the CO 2 footprint of native wood, that is, the emissions during wood harvesting, transportation, and processing, depends on the type of forest management practiced. This study quantifies the CO 2 footprint of native rough sawn lumber from forests with three types of harvesting: sustainable management, conventional management, and conventional selective extraction (deforestation). CO 2 emissions were analyzed from harvesting to the end of wood processing based on data from the literature and the Construction Environmental Performance Information System. The CO 2 footprint of rough sawn lumber varies between 25 and 19,860 kCO 2 /m 3 , with the lowest values for wood from sustainable management and the highest for conventional selective extraction. In addition, managed wood stores temporarily in its cell structure ~353kgC/m 3 . Native wood from sustainable harvesting can contribute to decarbonizing buildings, whereas wood from conventional harvesting and deforestation are relevant sources of CO 2 emissions, considering the wood life cycle.

Resmo O uso da madeira é frequentemente apontado como uma estratégia de descarbonização para a construção. Entretanto, a pegada de CO2 da madeira nativa, ou seja, que são as emissões decorrentes da sua exploração florestal, transporte e beneficiamento, depende do tipo de manejo florestal. Este estudo quantifica a pegada de CO2 da madeira nativa serrada bruta, proveniente de três tipos de exploração florestal: manejo sustentável, manejo convencional e extração seletiva convencional (desmatamento). Analisaram-se as emissões de CO2 da exploração florestal até o término do beneficiamento da madeira, com dados da literatura e do Sistema de Informação do Desempenho Ambiental da Construção. A pegada de CO2 da madeira serrada bruta varia entre 25 e 19.860 kgCO2/m3, com os menores valores para a madeira de manejo sustentável e os maiores para a madeira de extração seletiva convencional. Além disso, a madeira manejada estoca temporariamente, em sua estrutura celular, ~353 kgC/m3. Madeiras nativas de manejo florestal sustentável podem contribuir com a descarbonização dos edifícios, enquanto as madeiras de manejo convencional e, sobretudo, de desmatamentosão fontes expressivas de CO2 dentro do seu ciclo de vida.

Abstract Introduction. Tomato (Solanum lycopersicum L.) is considered one of the most important crops in the world. Genetic improvement of tomatoes has employed different methods to generate variability, and mutation the induction of mutations is one of the techniques used to obtaining improved varieties. The first step in using this tool is studying radiosensitivity to determine the irradiation dose to be used. Objective. To determine the radiosensitivity and the dose of cobalt-60 gamma rays to be used in three tomato varieties. Materials and methods. This research was conducted in January 2020 at the Instituto Nacional de Ciencias Agrícolas of Cuba. Seeds of three tomato varieties were irradiated with cobalt-60 gamma rays, with doses ranging from 100 Gy to 900 Gy, at intervals of 100 Gy; an unirradiated control was also used. The percentage of germination, plant height, and seedling survival were evaluated. Results. It was observed that higher irradiation dose reduced germination, survival, and plant height. The IDIAP T-7 and IDIAP T-9 varieties reduced germination at a dose of 400 Gy, while the DINA RPs cultivar reduced germination at 300 Gy. Genotypes showed survival values below 50 % at a dose of 800 Gy. Height reduction began at doses of 200 Gy for IDIAP T-7, 300 Gy for DINA RPs, and 400 Gy for IDIAP T-9. Conclusion. The DL-50 doses were identified as 692, 588, and 630 Gy, and the GR-50 doses were 407, 467, and 380 Gy for the IDIAP T-7, IDIAP T-9, and DINA RPs varieties, respectively. The GR-50 dose of each variety was selected for the mutation breeding program.

Resumen Introducción. El tomate (Solanum lycopersicum L.) es considerado uno de los cultivos más importantes en el mundo. La mejora genética del tomate ha empleado diferentes métodos para generar variabilidad, la inducción de mutaciones es una de las técnicas empleadas en la obtención de variedades mejoradas. El primer paso, en el uso de esta herramienta, es el estudio de radiosensibilidad para determinar la dosis de irradiación a emplear. Objetivo. Determinar la radiosensibilidad y la dosis de rayos gamma de cobalto-60 a emplear en tres variedades de tomate. Materiales y métodos. Esta investigación se desarrolló en enero del año 2020, en el Instituto Nacional de Ciencias Agrícolas de Cuba. Se irradiaron con rayos gamma de Cobalto-60 semillas de tres variedades de tomate, con dosis entre 100 Gy y 900 Gy, con intervalos de dosis de 100 Gy; también se empleó un control sin irradiar. Se evaluaron el porcentaje de germinación, la altura y la sobrevivencia de las plántulas. Resultados. Se observó que a mayores dosis de irradiación se redujo la germinación, la sobrevivencia y la altura de las plántulas. Las variedades IDIAP T-7 e IDIAP T-9 redujeron su germinación a la dosis de 400 Gy y el cultivar DINA RPs a los 300 Gy. Los genotipos presentaron valores de sobrevivencia por debajo del 50 % a la dosis de 800 Gy. La reducción de altura inició a la dosis de 200 Gy para la variedad IDIAP T-7, 300 Gy para DINA RPs y 400 Gy para IDIAP T-9. Conclusión. Las dosis de DL-50 identificadas fueron 692, 588 y 630 Gy y las dosis deGR-50 fueron 407, 467 y 380 Gy para las variedades IDIAP T-7, IDIAP T-9 Y DINA RPs, respectivamente. Se seleccionó la dosis GR-50 de cada una de las variedades para el programa de mejora por mutaciones.

Resumen: El objetivo de este estudio es evaluar el efecto de la atmósfera, definida como el diseño consciente del ambiente de la tienda para crear ciertas respuestas en los compradores, en los valores de compra, la actitud hacia la compra y las emociones sobre la intención de recompra en una tienda online, basado en el modelo Estímulo-Organismo-Respuesta (S-O-R, por sus siglas en inglés). Aunque estos elementos han sido estudiados ampliamente en el contexto de tiendas físicas, artículos recientes que analizan la influencia de estos elementos en el ambiente online muestran la relevancia de estudios como este en investigaciones académicas actuales de mercadeo. Los resultados de una encuesta realizada a 306 usuarios de una tienda farmacéutica online, residentes de Venezuela y otros países de América Latina, se analizaron usando ecuaciones estructurales. Los hallazgos permiten concluir que el uso del modelo S-O-R es apropiado en la predicción del comportamiento de compra online, y confirman que el valor de compra hedónico tiene un impacto directo significativo tanto en la actitud hacia las compras como en la compra emocional. Por otra parte, el valor de compra utilitario afecta negativamente la compra emocional y el factor informático favorece la actitud hacia las compras. Por último, la actitud hacia las compras y la compra emocional predicen la intención de recompra. Se discuten las implicaciones para los especialistas en marketing.

Abstract: The objective of this study was to evaluate the effect of the online store atmosphere, shopping values, attitude toward online shopping and emotions on the repurchase intention in an online store, based on the Stimulus-Organism-Response model (S-O-R). Although these elements have been studied in the context of brick-and-mortar stores, recent articles that analyze the influence of these elements in the online environment demonstrate the relevance of this study in current marketing research. The results of an online survey conducted with 306 users of an online pharmaceutical store, which included residents of Venezuela and of other Latin American countries, were analyzed using structural equations, evaluating both the measurement model and the relationship model. The findings allow us to conclude that the use of the S-O-R model is appropriate in predicting online purchase behavior, having achieved an adequate fit, and confirm that the hedonic purchase value has a significant direct impact on both the attitude toward online shopping and the emotional purchase. On the other hand, the utilitarian purchase value negatively affects the emotional purchase and the computer factor favors the attitude toward online purchase. Finally, the attitude toward online shopping and the emotional purchase predicts the repurchase intention. Implications for marketers are discussed.

Resumen: La investigación, con enfoque epistemológico cuantitativo y el paradigma positivista, tiene como objetivo definir la relación entre el marco regulatorio del sector financiero ecuatoriano y las condiciones de financiamiento a las pymes. Esta fue de tipo descriptivo-correlacional, permitiendo realizar un análisis descriptivo y factorial de variables vinculadas al conocimiento y aplicación de leyes y códigos regulatorios de 54 oficiales de crédito del sector bancario de El Oro, Ecuador. Se identificaron dos dimensiones: una relacionada con el marco regulatorio monetario y otra con códigos orgánicos. Las encuestas señalan que las leyes más aplicadas son: Ley General de Instituciones del Sector Financiero y Ley de Compañías. La primera regula la creación, funcionamiento y cierre de instituciones financieras privadas para proteger a la población y asegurar la estabilidad financiera; su cumplimiento es supervisado por la Superintendencia de Bancos. La segunda simplifica el proceso de constitución de empresas, permitiendo diversos tipos de compañías y flexibilidad en su estructura. Las regulaciones bancarias ecuatorianas han experimentado reformas para fortalecer la solidez y transparencia del sistema, como la Ley de Mercado de Valores y la Ley de Instituciones del Sistema de Seguros Privados, que contribuyen a la estabilidad, regulación, protección al consumidor financiero y promoción de la competencia, generando condiciones de financiamiento favorables, que incluyen confianza, tasas de interés competitivas y amplias opciones financieras.

Abstract: The research, with a quantitative epistemological approach and the positivist paradigm, aims to define the relationship between the regulatory framework of the Ecuadorian financial sector and the financing conditions for SMEs. This was of a descriptive-correlational type, allowing a descriptive and factorial analysis of variables linked to the knowledge and application of laws and regulatory codes of 54 credit officers from the banking sector of El Oro, Ecuador. Two dimensions were identified: one related to the monetary regulatory framework and another with organic codes. Surveys indicate that the most applied laws are: General Law of Financial Sector Institutions and Companies Law. The first regulates the creation, operation and closure of private financial institutions to protect the population and ensure financial stability; Its compliance is supervised by the Superintendency of Banks. The second simplifies the business incorporation process, allowing various types of companies and flexibility in their structure. Ecuadorian banking regulations have undergone reforms to strengthen the soundness and transparency of the system, such as the Securities Market Law and the Law of Institutions of the Private Insurance System, which contribute to stability, regulation, financial consumer protection and promotion of competition, generating favorable financing conditions, which include confidence, competitive interest rates and broad financial options.

ABSTRACT: This research evaluated different rice genotypes regarding physicochemical and instrumental parameters of grain quality and associated the data with sensory analysis to support the creation of rules for classification of the culinary quality of rice (texture), based on isolated or combined parameters. The combination of amylose content and gelatinization temperature was able to predict the rice quality. According to the sensorial panel, the instrumental stickiness was able to segregate rice with very low amylose content or waxy to the other ones. Regarding pasting properties, rice that presented high final viscosity (310-480 RVU), setback (165-245 RVU), and pasting temperature (78 - 88 °C), and low values for breakdown (15-120 RVU), associated with a high stickiness (>-5N) was desirable by the Brazilian consumers. The classification rules created through the relationship between the physicochemical parameters and the texture profile evaluated by the sensory panel will help to verify the culinary profile of the rice samples (through free software), which makes it easier to predict the probability of rice meeting the desired quality standards.

RESUMO: Este trabalho avaliou diferentes genótipos de arroz quanto a parâmetros físico-químicos e instrumentais de qualidade do grão e associou os dados à análise sensorial para subsidiar a criação de regras de classificação da qualidade culinária do arroz (textura), com base em parâmetros isolados ou combinados. A combinação do teor de amilose e temperatura de gelatinização foi capaz de predizer a qualidade do arroz. De acordo com o painel sensorial, a pegajosidade instrumental foi capaz de segregar arroz com baixo teor de amilose ou ceroso dos demais. Em relação às propriedades de pasta, o arroz que apresentou alta viscosidade final (310-480RVU), retrogradação (165-245RVU) e temperatura de pasta (78-88 °C) e baixos valores de quebra pasta (15-120RVU), associados a uma alta pegajosidade (> -5N) será desejável pelos consumidores brasileiros. As regras de classificação criadas por meio da relação entre os parâmetros físico-químicos e o perfil de textura avaliado pelo painel sensorial ajudarão a verificar o perfil culinário das amostras de arroz (por meio de um software livre), o que torna mais fácil prever a probabilidade de o arroz atender aos padrões de qualidade desejados.

ABSTRACT: Members of the genus Lanius, known as shrikes, are economically important song birds distributed widely in several Asian countries. DNA sequencing, based on a partial segment of the cytochrome oxidase b (Cyt b) gene, was used to determine genetic variations and population genetic structure in four populations of shrike samples from north, east, and west Pakistan. We observed nucleotide diversities in L. isabellinus(= 0.02), L. schach(= 0.005), L. vittatus(= 0.004) and L. lahtora(= 0.008) . FST values were significant (P < 0.05) in all species populations apart from L. isabellinus, which were non-significant. The negative values of Fu’s Fs and Tajima’s D showed significant population expansion in three species, L. schach, L. vittatusand L. Lahtora, whereas they were insignificant in populations of L. isabellinus. Fu’s Fs and Tajima’s D values explain that a strong genetic structure is present among members of L. isabellinus. On this basis, it is inferred that strong genetic structuring in L. isabellinuspopulations within this region was largely shaped by a common origin, with secondary influences from geographical factors and isolation.

RESUMO: Membros do gênero Lanius, conhecidos como picanços, são pássaros canoros economicamente importantes, amplamente distribuídos em vários países asiáticos. O sequenciamento de DNA, baseado em um segmento parcial do gene citocromo oxidase b (Cyt b), foi usado para determinar as variações genéticas e a estrutura genética da população em quatro populações de amostras de picanço do norte, leste e oeste do Paquistão. As diversidades de nucleotídeos em L. isabellinus (= 0,02), L. schach (= 0,005), L. vittatus (= 0,004) e L. lahtora (= 0,008) foram observadas. Os valores de FST foram significativos (P < 0,05) em todas as populações de espécies, exceto L. isabellinus, que não foram significativos. Os valores negativos de Fs de Fu e D de Tajima mostraram expansão populacional significativa em três espécies, L. schach, L. vittatus e L. Lahtora, enquanto foram insignificantes em populações de L. isabellinus. Os valores Fs de Fu e D de Tajima explicam que uma forte estrutura genética está presente entre os membros de L. isabellinus. Com base nisso, infere-se que a forte estruturação genética nas populações de L. isabellinus nessa região foi amplamente moldada por uma origem comum, com influências secundárias de fatores geográficos e isolamento.

Resumo A influência dos média sociais no campo do jornalismo, hoje incontornável, manifesta-se em várias vertentes, criando desafios que não podem ser ignorados pelos profissionais. Enquanto fontes, estão a ser cada vez mais utilizados, contribuindo para a emergência de novas dinâmicas de produção noticiosa, em particular na cobertura de acontecimentos em continuidade, nos quais impera a velocidade de transmissão e o imediatismo constitui um valor em si mesmo, incentivando a extração de conteúdos disponíveis na internet, sem tempo para escrutínio. Neste artigo, o fenómeno é enquadrado numa perspetiva ética. Através da análise de 32 códigos deontológicos - e instrumentos semelhantes - que incorporam esta realidade em partes específicas foram identificados valores e princípios jornalísticos neles inscritos acerca das modalidades de recolha de informação, sobretudo em redes sociais digitais. A exigência de verificação e validação do material e de identificação da fonte, procedimentos tradicionais, é predominante, atentos os potenciais riscos para o rigor de uma narrativa jornalística. Também é detetada, na maioria dos códigos integrados no corpus, a preocupação de acautelar o dano na esfera privada de cidadãos, eventualmente decorrente da difusão de material. Não se trata apenas de proteger a privacidade, em geral, mas de ponderar questões de grande sensibilidade a ela associáveis: a vulnerabilidade e dor em que possam encontrar-se os autores das postagens e a presença nas redes de vítimas ou cidadãos menores de idade.

Abstract The inescapable influence of social media on journalism has introduced a multitude of challenges that professionals in the field cannot afford to overlook. Increasingly used as sources, social media platforms contribute significantly to the evolution of new dynamics in news production. This is particularly evident in the coverage of unfolding events, prioritising speed of transmission and immediacy as inherent values. This emphasis often encourages the rapid extraction of content available on the internet, leaving minimal time for thorough scrutiny. This article delves into the phenomenon from an ethical standpoint. Through an analysis of 32 codes of ethics - and analogous instruments - that specifically address this evolving reality, it identifies journalistic values and principles concerning information-gathering methods, especially pertaining to digital social networks. The primary emphasis remains on the requirement to verify and validate the material while identifying sources following traditional procedures, given the potential risks to the integrity of journalistic narratives. Most codes in the corpus also prioritise safeguarding citizens’ private sphere, possibly stemming from the dissemination of material. This concern extends beyond general privacy protection, encompassing the highly sensitive issues associated with it: the vulnerability and emotional distress experienced by authors of social media posts and the presence of victims or minors on social networks.

Resumo Esta pesquisa tem como objetivo compreender as dinâmicas de participação presentes em veículos informativos produzidos por cidadãos não-jornalistas, no interior de Portugal. A partir de um estudo exploratório, são analisadas duas iniciativas desenvolvidas por comunidades localizadas no interior do país, o Vela Notícias, na região Centro, e o Jornal da Aldeia, na região do Alentejo. Estas são entendidas como objetos empíricos de um fenómeno que reflete o distanciamento e os constrangimentos dos média tradicionais, o desejo das populações destes territórios de partilharem conhecimento de interesse local e a necessidade de os cidadãos se sentirem representados social e culturalmente. As duas iniciativas surgiram em regiões desertificadas, com menos de 1.000 habitantes, e envelhecidas, segundo os Censos 2021 (Instituto Nacional de Estatística, 2021). A fim de compreender e discutir tais questões, além da revisão da literatura pertinente ao tema, realizaram-se entrevistas semiestruturadas, como procedimento metodológico, aos participantes envolvidos na produção informativa dos dois média comunitários. A importância do estudo consiste em compreender dinâmicas comunicacionais de proximidade que envolvem cidadãos não-jornalistas. Os cidadãos das duas freguesias participam na criação de conteúdos, na escolha dos assuntos, na edição e na distribuição dos periódicos. A produção não está submetida às lógicas de seleção, filtragem e hierarquização jornalísticas. Ainda assim, os entrevistados demonstram interesse e confiança nas informações publicadas. O interesse em participar relaciona-se com o desejo de partilha de valores comuns e vínculos culturais, que contam ainda com o sentimento de pertença e de responsabilidade social.

Abstract This research seeks to delve into the dynamics of participation within news platforms curated by non-professional journalists residing in inland Portugal. Through an exploratory study, two initiatives originating from communities located in the country’s inland areas are analysed: Vela Notícias, in the Centre region, and Jornal da Aldeia, in the Alentejo region. These initiatives serve as empirical objects illustrating a phenomenon that reflects the shift away from traditional media, the community’s eagerness to disseminate locally pertinent knowledge, and the citizens’ yearning for social and cultural representation. Both initiatives have emerged in ageing and sparsely populated regions, with fewer than 1,000 inhabitants, according to the 2021 Census (Instituto Nacional de Estatística, 2021). To understand and address these concerns, alongside a thorough review of pertinent literature, semi-structured interviews were conducted as a methodological approach involving participants engaged in information production for the two community media outlets. The significance of this study lies in unravelling the intricacies of proximity communication dynamics spearheaded by non-journalist citizens. The residents of both parishes actively contribute to content creation, topic selection, editing, and distribution of the newspapers. Production operates outside the norms of journalistic selection, filtering, and hierarchy. Nevertheless, interviewees exhibit keen interest and confidence in the published information. The motivation for participation stems from a desire to share common values and cultural connections, fostering a sense of belonging and social responsibility.

RESUMEN Este artículo presenta los resultados de una investigación empírica cuyo objetivo fue identificar factores críticos que contribuyeron para la culminación exitosa de los itinerarios formativos de un grupo de graduados de Educación de Jóvenes y Adultos Integrada con la Formación Profesional en el nivel secundario brasileño. Se aplicó un análisis de contenido a los datos obtenidos a través de entrevistas semidirigidas a diez graduados. Exploramos la noción de posicionamiento, como fenómeno social que circunscribe la posición que ocupa un individuo o grupo en un sistema social determinado (Bernstein, 1996) en línea con las disposiciones socioafectivas y cognitivas relacionadas con los procesos de placer/displacer presentes en el contexto escolar y con las representaciones y concepciones de los contenidos, respectivamente (Bourgeois, 1999). Los resultados apuntan a la elevación del posicionamiento en estructuras jerárquicas circunscritas por la escolaridad, el aprendizaje, el conocimiento, las relaciones sociocognitivas y la perspectiva profesional, que se correlacionan con el desarrollo de disposiciones socioafectivas y cognitivas en las dimensiones motivaciones, aspiraciones, valores apropiados y características curriculares, concretamente aprendizaje colaborativo y metodología de enseñanza.

RESUMO Este artigo apresenta os resultados de uma pesquisa empírica cujo objetivo foi identificar fatores críticos que contribuíram para o sucesso na conclusão dos percursos formativos de um grupo de egressos da Educação de Jovens e Adultos Integrada à Formação Profissional no nível secundário brasileiro. Foi aplicada a análise de conteúdo dos dados obtidos através de entrevistas semi-dirigidas com dez egressos. Exploramos a noção de posicionamento, enquanto fenômeno social que circunscreve a posição que um indivíduo ou grupo ocupa num dado sistema social (Bernstein, 1996) em consonância com as disposições socioafetivas e cognitivas relacionadas com os processos de prazer/desprazer presentes no contexto escolar e com as representações e conceções do conteúdo, respetivamente (Bourgeois, 1999). Os resultados apontam para a elevação do posicionamento em estruturas hierárquicas circunscritas pela escolaridade, aprendizagem, conhecimento, relações sociocognitivas e perspectiva profissional, as quais estão correlacionadas com o desenvolvimento de disposições socioafetivas e cognitivas nas dimensões motivações, aspirações, valores adequados e características curriculares, nomeadamente aprendizagem colaborativas e metodologia de ensino.

Abstract This article presents the results of an empirical study whose aim was to identify critical factors that contributed to the successful completion of the educational trajectories of a group of former students of a Brazilian secondary level course integrating Youth and Adult Education with Vocational Education. Content analysis was applied to the data obtained through semi-directive interviews with ten former students. We explored the notion of positioning, as a social phenomenon that circumscribes the position that an individual or group occupies in a given social system (Bernstein, 1996) in line with the socio-affective and cognitive dispositions related to the processes of pleasure/displeasure present in the school context and with the representations and conceptions of the content, respectively (Bourgeois, 1999). The results point to higher positioning in hierarchical structures circumscribed by schooling, learning, knowledge, socio-cognitive relations, and professional outlook, which are correlated with the development of socio-affective and cognitive dispositions in the dimensions of motivations, aspirations, appropriate values and curricular characteristics, namely collaborative learning, and teaching methodology.

Resumen (Introducción): La vertiente Caribe de América Central se encuentra a barlovento de los vientos alisios asociados con la Alta Subtropical del Atlántico Norte y presenta un ciclo anual de precipitación bimodal, donde se observa un mínimo relativo en los meses de septiembre y octubre. (Objetivo): Caracterizar el descenso observado en las lluvias en esta región en ese bimestre, estimando, para cada evento, las variables asociadas con los valores del día del inicio, día del mínimo, día del final, duración, intensidad y magnitud, en el periodo 1979-2010. (Metodología): Se usaron 31 registros diarios de estaciones pluviométricas. Se examinó, en cada una de ellas, los meses de julio a noviembre, para encontrar los valores del mínimo, la fecha del mínimo, del inicio y del final, duración e intensidad. Se exploró la ocurrencia de alguna tendencia temporal o espacial en las características de los eventos. Por último, se revisaron diferentes índices climáticos y fuentes documentales para identificar las posibles causas sinópticas de los descensos más fuertes en las lluvias. (Resultados): El inicio de los eventos se observó alrededor del 3 de septiembre, su mínimo el 23 de septiembre y el final 12 de octubre, con una duración aproximada de 39 días. Los eventos tienden a suceder primeramente en las estaciones ubicadas al noroeste del istmo. Los eventos más secos sucedieron bajo condiciones propicias para la ocurrencia de vientos con componente suroeste-oeste sobre la región. (Conclusiones): El conocimiento sobre estas características de la precipitación ayuda en la planificación de sectores socioeconómicos claves en América Central ante eventuales eventos hidrometeorológicos adversos.

Abstract (Introduction): The Caribbean slope of Central America is located windward about the trade winds associated with the North Atlantic Subtropical High and the rains present a bimodal annual cycle, observing a relative minimum in the months of September and October. (Objective): Characterize the observed decrease in rainfall in this region for this bimester, estimating for each event, the variables associated with the values of the onset day, minimum day, demise day, duration, intensity, and magnitude, in 1979-2010. (Methodology): A set of 31 daily records from rain gauge stations was used. In each of them, the months from July to November were examined to find the values of the minimum, the date of the minimum, the onset and the demise, duration, and intensity. The occurrence of any temporal or spatial trend in these characteristics of the events was explored. Finally, different climatic indices and documentary sources were reviewed to identify the possible synoptic causes of the strongest decreases in rainfall. (Results): The beginning of the events was observed around September 3rd, their minimum on September 23rd and the end on October 12th, with an approximate duration of 39 days. Events tend to happen earlier at stations located northwest on the isthmus. The driest events occurred under favorable conditions for the occurrence of winds with a southwest-west component over the region. (Conclusions): Knowledge about these characteristics of precipitation helps in the activity planning of key socioeconomic sectors in Central America in case of adverse hydrometeorological events.

Resumen (Introducción): La capacidad productiva de una plantación forestal depende principalmente de las características fisicoquímicas del suelo, así como del manejo silvicultural necesario para un óptimo desarrollo de los árboles. (Objetivo): El objetivo de esta investigación fue la evaluación del efecto de la fertilización sobre plantaciones forestales clonales de Gmelina arborea Roxb. ex Sm., de tres años, en el Pacífico Norte y Sur de Costa Rica. (Metodología): El estudio se realizó en 2 ensayos experimentales del Instituto de Investigación y Servicios Forestales ubicados en La Esperanza, Cóbano (ensayo 1) y en Rancho Quemado, Bahía Drake (ensayo 2). Se establecieron 5 bloques completos, al azar, con 4 tratamientos de fertilización con el abono 19-4-19-2-0,1(B)-1,8(S)-,1(Zn). Se realizó un análisis de varianza y comparación de medias de los incrementos medios anuales del DAP, la altura y el volumen total de los árboles utilizando la prueba de Tukey. (Resultados): Los resultados muestran que el sitio con mayor fertilidad natural presenta aumento en el crecimiento de los árboles; sin embargo, no existen diferencias estadísticamente significativas entre todos los tratamientos aplicados. El sitio de menor fertilidad natural se ubica en Bahía Drake y presentó diferencias estadísticamente significativas en algunos tratamientos en términos de volumen total. (Conclusiones): La fertilización continua tienen un impacto positivo en el crecimiento dasométrico en plantaciones de G. arborea que presenten bajos contenidos de calcio (< 4.5 cmol L-1), valores bajos en capacidad de intercambio catiónico efectiva (< 7.8 cmol L-1) y alta saturación de acidez (> 19.4 %).

Abstract (Introduction): The productive capacity of a forest plantation depends mainly on the physicochemical characteristics of the soil, as well as the necessary silvicultural management for optimal tree development. (Objective): The objective of this research was the evaluation of the effect of fertilization on clonal forest plantations of Gmelina arborea Roxb. ex Sm. 3 years old, in the North and South Pacific of Costa Rica. (Methodology): The study was carried out in 2 experimental trials of the Forestry Research and Services Institute located in La Esperanza, Cóbano (trial 1) and in Rancho Quemado, Drake Bay (trial 2). Five complete blocks were established at random with four fertilization treatments with the fertilizer 19-4-19-2-0.1(B)-1.8(S)-.1(Zn). An analysis of variance and comparison of means of the mean annual increments of DBH, height and total volume of the trees was carried out, using the Tukey test. (Results): The results show that the site with the highest natural fertility presents a greater growth of the trees, however, there are no statistically significant differences between all the treatments applied. The site with the lowest natural fertility is located in Bahía Drake and it did present statistically significant differences in some treatments in terms of total volume. (Conclusions): Continuous fertilization have a positive impact on the dasometric growth in G. arborea plantations that present low calcium contents (< 4.5 cmol L-1), low values of effective cation exchange capacity (<7.8 cmol L-1) and high acidity saturation (> 19.4 %).

Abstract There is a growing interest in reducing energy consumption in the economic sectors, where the residential sector is a substantial consumer of energy in societies and therefore, a focus of attention for efficiency and renewable energy generation policies. In Ecuador, residential consumption represents 1/4 of the total electricity demanded by the socioeconomic system. Household composition has changed due to demographic dynamics, socioeconomic improvements and social justice efforts, which impacts electricity consumption. The aim of this study is to analyze the dynamics of energy consumption in Ecuador´s residential sector based on the construction of household typologies under the hierarchy of demographic, geographic, economic and technical variables using a top-down and bottom-up methodology and the application of MuSIASEM for which statistical information from National Surveys and Censuses was used, which allowed the construction of household typologies and their consumption pattern. The results show heterogeneous electricity consumptions in the 4.5 million households in 2017 hierarchically divided into 240 typologies. The pattern varies from the lowest consumption households with 50 KWh/month to the highest consumption of 350 KWh/month. For example, in the urban area the highest rate is concentrated in households made up of more than 8 people with rates between 150 to 180 KWh/month, while in the rural area the values range from 90 to 120 KWh/month but differ by geographic location and male or female headship. Likewise, the data allowed scaling to aggregate levels where it is shown that, of the total annual electricity consumption of 6,428 GWh, 54% of the consumption was concentrated in the coastal region, which concentrates 51% of the total households in the residential sector of Ecuador.

Resumen Existe un interés creciente por reducir el consumo de energía en los sectores económicos, donde el sector residencial es un consumidor sustancial de energía en las sociedades y por tanto, un foco de atención para las políticas de eficiencia y de generación energética renovable. En Ecuador, el consumo residencial representa un 1/4 del total de electricidad que demanda el sistema socioeconómico. La conformación de los hogares ha cambiado por la dinámica demográfica, mejoras socioeconómicas y los esfuerzos por la justicia social, lo cual impacta en el consumo de electricidad. El objetivo del estudio es analizar la dinámica del consumo de energía en el sector residencial del Ecuador a partir de la construcción de tipologías de hogares bajo la jerarquización de variables demográficas, geográficas, económicas y técnicas utilizando una metodología top-down y bottom-up y la aplicación de MuSIASEM para lo cual se utilizó información estadística de Encuestas y Censos Nacionales, que permitió construir las tipologías de hogares y su patrón de consumo. Los resultados muestran consumos de electricidad heterogéneos en los 4,5 millones de hogares presentes en 2017 divididos jerárquicamente en 240 tipologías. El patrón varía desde los hogares de menor consumo con 50 KWh/mes hasta los de mayor consumo de 350 KWh/mes. Por ejemplo, en la zona urbana la mayor tasa se concentra en los hogares conformados por más de 8 personas con tasas entre 150 a 180 KWh/mes, mientras que en la zona rural los valores oscilan entre 90 a 120 KWh/mes, pero difieren por ubicación geográfica y por su jefatura masculina o femenina. Igualmente, los datos permitieron escalar a niveles agregados donde se muestra que, del total de consumo anual de electricidad de 6,428 GWh, el 54% del consumo se concentró en la región Costa que concentra el 51% del total de hogares del sector residencial del Ecuador.

Abstract The Puerto Pizarro mangrove is part of the Tumbes mangrove, the largest in Peru; it is also the mangrove with the greatest anthropic impact in the region; in this area, no studies have been carried out on the status of its population of Rhizophora mangle, the most important mangrove species in the Peruvian mangroves. The objective of this research was to establish the structural characteristics of R. mangle in the Puerto Pizarro mangrove. The study was carried out by subdividing the research area into three zones (A, B and C), in which 41 plots of 1 ha each were selected, in each plot a sub-area of 0.25 ha (50 m x 50 m) was taken). In these sub-areas, mangrove trees of the species Rhizophora mangle, Laguncularia racemosa and Avicennia germinans were evaluated regarding their structural characteristics: diameter at breast height (DBH), height, basal area, density, frequency, dominance and index value of ecological importance (IVI). It was found that R. mangle had a greater DAP, height and basal area than the other species; also, higher density, frequency, dominance and relative IVI (adjusted to 100%) than the other species with values of 51.5%, 100%, 82.6% and 53.3%, respectively. The research findings allow us to conclude that the population of R. mangle in the Puerto Pizarro mangrove is a mature population, with a predominance of stems and latizales. However, its structural characteristics are not homogeneous throughout the Puerto Pizarro area, since zone A, with less anthropic impact and lower salinity, has R. mangle trees with better structural characteristics than those in zones B and C in which there is greater anthropic activity and greater salinity.

Resumen El manglar de Puerto Pizarro forma parte del manglar de Tumbes, el más grande del Perú; es también el manglar con mayor impacto antrópico en la región; en este no se han realizado estudios sobre el estado de su población de Rhizophora mangle, la especie de mangle más importante de los manglares peruanos. Esta investigación buscaba establecer las características estructurales de R. mangle en el manglar de Puerto Pizarro. El estudio se realizó subdividiendo el área de investigación en tres zonas (A, B y C), en las cuales se seleccionaron 41 parcelas de 1 ha cada una, en cada parcela se tomó una sub-área de 0,25 ha (50 m x 50 m). En estas sub-áreas se evaluaron los árboles de mangle de las especies Rhizophora mangle, Laguncularia racemosa y Avicennia germinans respecto a sus características estructurales diámetro a la altura del pecho (DAP), altura, área basal, densidad, frecuencia, dominancia e índice de valor de importancia ecológica (IVI). Se encontró que R. mangle presentó un mayor DAP, altura y área basal que las otras especies; así también, mayor densidad, frecuencia, dominancia e IVI relativos (ajustados al 100%) que las otras especies con valores de 51,5%, 100%, 82,6% y 53,3%, respectivamente. Los hallazgos de la investigación permiten concluir que la población de R. mangle del manglar de Puerto Pizarro es una población madura, con predominancia de fustales y latizales. En Puerto Pizarro, sus características estructurales no son homogéneas, ya que la zona A, con menor impacto antrópico y menor salinidad, presenta árboles de R. mangle con mejores características estructurales que los de las zonas B y C, donde hay mayor actividad antrópica y mayor salinidad.

Abstract: The paper presents a novel control strategy for islanded Microgrids, based on hierarchical control and modified droop control. The robust control strategy presented allows stability voltage improvement and its transient behavior. Which subscribes to verify the performance of the proposed strategy compared with a conventional PI controller. The implementation of renewable energy sources such as photovoltaics, which introduces variability in generation due to fluctuating factors such as radiation. Due to technological advances demand a huge amount of electricity, therefore Renewable Energy Resources (RES) must be near the electrical demand is huge, in addition they are implemented in rural places, where electric utility is not able to provide the service. However, the implementation of these new systems implies facing new challenges for the correct operation of Microgrid connected or islanded from the conventional system.

Resumen: El constante avance de la tecnología requiere una gran cantidad de energía, por ello se ha propuesto la inclusión de fuentes de energía renovable (RES) cerca de los centros de carga. La implementación de fuentes de energía renovable como la energía fotovoltaica, que introduce variabilidad en la generación debido a factores fluctuantes como la radiación. Estas RES son implementadas también en sectores donde el sistema eléctrico convencional no es capaz de llegar, de esta manera se garantiza el abastecimiento de energía eléctrica a toda la población. El paper presenta una novedosa estrategia de control de Micro-redes aisladas, basado en el control jerárquico y control droop modificado. Esta estrategia robusta permite mejorar la estabilidad de voltaje y su comportamiento transitorio. Se implementa una Micro-red de referencia con dos fuentes fotovoltaicas con valores nominales. Lo que permite verificar el desempeño de la estrategia propuesta comparando con un controlador PI convencional. Sin embargo, la implementación de estos nuevos sistemas implica retos de control para que su funcionamiento sea correcto, indiferente que la Micro-red funcione de forma conectada o aislada a la red convencional.

Abstract: This paper shows an analysis of the overvoltages caused by atmospheric impulses in transmission systems with discontinuities, overhead transmission lines, and insulated cables using the Alternative Transients Program (ATP) software. The analysis is performed considering direct lightning impact on the guard cable or transmission tower and the direct impact on the phase conductor, when shielding failure occurs. In order to determine voltages at the ends of the insulated cable and analyze its potential affectation, a test transmission system has been implemented, and Base Case has been defined; this case is formed by six transmission towers and insulated cable protected in both sides by surge arresters. The effect of varying parameters that affect the magnitude of the voltages at both the input and the output of the insulated cable is analyzed in order to determine the most critical situation that can influence the maximum overvoltage values in the insulated cable. The results confirm the effect that the discontinuities between two components of an electrical system have on the voltage magnitudes that may occur in a system due to atmospheric discharges.

Resumen: El artículo muestra un análisis de los sobrevoltajes ocasionados por impulsos atmosféricos en sistemas de transmisión con discontinuidades, esto es, líneas de transmisión aéreas que se conectan a cables aislados, las simulaciones se hacen mediante el uso del software Alternative Transients Program (ATP). El análisis se realiza considerando descargas atmosféricas directas en el cable de guarda o torre de transmisión, y cuando ocurre una falla del apantallamiento de la línea, esto es un impacto directo del rayo en el conductor de fase. Para la determinación de los voltajes en los extremos del cable aislado y analizar su potencial afectación, se ha implementado un sistema de transmisión de prueba en el cual se ha definido un Caso Base, que está compuesto por seis torres de transmisión y un cable aislado protegido en ambos extremos por dispositivos descargadores de sobretensión, DPS. Se analiza el efecto de variar algunos parámetros que inciden en la magnitud de los voltajes tanto al ingreso del cable aislado como a la salida, con el fin de determinar la situación más crítica que puede influir en los valores máximos de sobrevoltaje en el cable aislado. Los resultados obtenidos permiten confirmar el efecto que tienen las discontinuidades presentes entre dos componentes de un sistema eléctrico en las magnitudes de voltaje que puedan producirse en un sistema debido a descargas atmosféricas.