Determinación de la Eficiencia de Campo para el Sistema de Máquinas de alza y transporte en el Ingenio Pantaleón utilizando diagramas cíclicos, en la zafra azucarera 2010/2011

The agricultural engineering, related to the mechanized processes, is not limited to estimate the machines performance in a fixed state of the system. Indeed, it tries to predict the exact state of the system at any time with the purpose of identifying the activities of the machine system, and find the field efficiencies of the system, and labor efficiency. Furthermore, conduct an analysis of the cycle times in real-time. This study helped to find in practice, at a pilot level, the field efficiencies; labor efficiency, and the machines performance. Moreover, we identified the factors that restrict the machine system in the process of rise and transport of sugar cane harvest of Ingenio Pantaleón in El Viejo, Chinandega, Nicaragua DOI: http://dx.doi.org/10.5377/nexo.v25i2.676La ingeniería agrícola relacionada con los procesos mecanizados, no se limita a estimar sólo la operación de las máquinas agropecuarias en un estado fijo del sistema, sino que trata de predecir el estado exacto del sistema en cualquier instante, no solo con el objetivo de identificar las actividades de todo el sistema de máquinas, sino también encontrar las eficiencias de campo del sistema, la eficiencia de mano de obra y además, realizar un análisis de los tiempos de los ciclos en tiempo real. Este estudio permitió determinar -a nivel piloto-, en la práctica las eficiencias de campo; mano de obra, el rendimiento de las maquinas, así como identificar los factores que restringen el sistema de máquinas en el proceso de Alza y Transporte de Cosecha de la caña de azúcar en el Ingenio Pantaleón, ubicado en El Viejo, Chinandega, Nicaragua.DOI: http://dx.doi.org/10.5377/nexo.v25i2.676

Determinación de la Eficiencia de Campo para el Sistema de Máquinas de alza y transporte en el Ingenio Pantaleón utilizando diagramas cíclicos, en la zafra azucarera 2010/2011

La ingeniería agrícola relacionada con los procesos mecanizados, no se limita a estimar sólo la operación de las máquinas agropecuarias en un estado fijo del sistema, sino que trata de predecir el estado exacto del sistema en cualquier instante, no solo con el objetivo de identificar las actividades de todo el sistema de máquinas, sino también encontrar las eficiencias de campo del sistema, la eficiencia de mano de obra y además, realizar un análisis de los tiempos de los ciclos en tiempo real. Este estudio permitió determinar -a nivel piloto-, en la práctica las eficiencias de campo; mano de obra, el rendimiento de las maquinas, así como identificar los factores que restringen el sistema de máquinas en el proceso de Alza y Transporte de Cosecha de la caña de azúcar en el Ingenio Pantaleón, ubicado en El Viejo, Chinandega, Nicaragua. DOI: http://dx.doi.org/10.5377/nexo.v25i2.67

Tracing Water Sources and Fluxes in a Dynamic Tropical Environment: From Observations to Modeling

Código de proyecto: Isotope Network for Tropical Ecosystem Studies (ISONet). Producción relacionada con el Observatorio del Agua y Cambio Global (OACG).Tropical regions cover approximately 36% of the Earth’s landmass. These regions are home to 40% of the world’s population, which is projected to increase to over 50% by 2030 under a remarkable climate variability scenario often exacerbated by El Niño Southern Oscillation (ENSO) and other climate teleconnections. In the tropics, ecohydrological conditions are typically under the influence of complex land-ocean-atmosphere interactions that produce a dynamic cycling of mass and energy reflected in a clear partition of water fluxes. Here, we present a review of 7 years of a concerted and continuous water stable isotope monitoring across Costa Rica, including key insights learned, main methodological advances and limitations (both in experimental designs and data analysis), potential data gaps, and future research opportunities with a humid tropical perspective. The uniqueness of the geographic location of Costa Rica within the mountainous Central America Isthmus, receiving moisture inputs from the Caribbean Sea (windward) and the Pacific Ocean (complex leeward topography), and experiencing strong ENSO events, poses a clear advantage for the use of isotopic variations to underpin key drivers in ecohydrological responses. In a sequential approach, isotopic variations are analyzed from moisture transport, rainfall generation, and groundwater/surface connectivity to Bayesian and rainfall-runoff modeling. The overarching goal of this review is to provide a robust humid tropical example with a progressive escalation from common water isotope observations to more complex modeling outputs and applications to enhance water resource management in the tropics.UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Básicas::Centro de Investigaciones Geofísicas (CIGEFI)UCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de FísicaUCR::Vicerrectoría de Docencia::Ciencias Sociales::Facultad de Ciencias Sociales::Escuela de Geografí

Hydrological dataset of a sub-humid continental plain basin (Buenos Aires, Argentina)

The Chaco-Pampean Plain (Argentina) is the strongest economic region and the most inhabited in the country, comprising approximately 66% of the country's population (26,500 million). In this region, surface slopes are very low (<0.1%) and due to the current climatological features, floods and droughts alternate over time. Salinity and alkalinity of water and soil increase towards the flattest sector of the basin, as well as the contents of arsenic and fluoride, which restrict their human use. Worldwide, population growth and global warming, in addition to political decisions, are leading to abrupt land use changes. Under this premise, identifying and quantifying the hydrological processes that control water quantity and its chemical quality become an imperative task. This data article provides a long-term hydrological dataset from a sector of the Chaco-Pampean Plain, the Del Azul creek basin. Hydrological data such as flow rates and piezometric levels, and physical–chemical (i.e., major and minor solutes, and trace elements) and isotopic (δ18O, δ2H; and d-excess) data from rainwater, surface (creek and wetland) and groundwater (at two depths) are available. Rainwater samples are derived from three precipitation collectors installed at different altitudes (monitoring period: 2010–2019; n = 57). Surface water samples were collected at three sampling sites located along the Del Azul Creek and six wetlands (monitoring period: 2018–2019; n = 12). Groundwater samples were collected from 17 piezometers with depths ranging between 3 and 10 m, and from 12 piezometers of 30 m depth, all located throughout the entire basin (monitoring period: 2018–2019; n = 115). Sampling campaigns were performed during the austral dry (summer) and wet (spring) seasons. This dataset provides useful information to understand a) how water moves from recharge to discharge areas, b) how water acquires salinity, and c) how particular solutes of concern, such as arsenic and fluoride, are distributed in space and time across in an extensive plain.Fil: Zabala, Maria Emilia. Comisión de Investigaciones Científicas de la Provincia de Buenos Aires. Instituto de Hidrología de Llanuras "Dr. Eduardo Jorge Usunoff". - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Instituto de Hidrología de Llanuras "Dr. Eduardo Jorge Usunoff". - Universidad Nacional del Centro de la Provincia de Buenos Aires. Instituto de Hidrología de Llanuras "Dr. Eduardo Jorge Usunoff"; ArgentinaFil: Sánchez Murillo, Ricardo. Universidad Nacional de Costa Rica; Costa RicaFil: Dietrich, Sebastián. Comisión de Investigaciones Científicas de la Provincia de Buenos Aires. Instituto de Hidrología de Llanuras "Dr. Eduardo Jorge Usunoff". - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Instituto de Hidrología de Llanuras "Dr. Eduardo Jorge Usunoff". - Universidad Nacional del Centro de la Provincia de Buenos Aires. Instituto de Hidrología de Llanuras "Dr. Eduardo Jorge Usunoff"; ArgentinaFil: Gorocito, Martin. Universidad Nacional del Centro de la Provincia de Buenos Aires. Instituto de Hidrología de Llanuras "Dr. Eduardo Jorge Usunoff"; ArgentinaFil: Vives, Luis Sebastián. Universidad Nacional del Centro de la Provincia de Buenos Aires. Instituto de Hidrología de Llanuras "Dr. Eduardo Jorge Usunoff"; ArgentinaFil: Manzano, Marisol. Universidad Politécnica de Cartagena. Departamento de Ingeniería Minera y Civil; EspañaFil: Varni, Marcelo Raúl. Universidad Nacional del Centro de la Provincia de Buenos Aires. Instituto de Hidrología de Llanuras "Dr. Eduardo Jorge Usunoff"; Argentin

Neurorrestauración tras la isquemia cerebral: papel de los neurotransmisores en la neurogénesis postisquémica

Introduction. Brain ischemia and reperfusion produce alterations in the microenvironment of the parenchyma, including ATP depletion, ionic homeostasis alterations, inflammation, release of multiple cytokines and abnormal release of neurotransmitters. As a consequence, the induction of proliferation and migration of neural stem cells towards the peri-infarct region occurs. Development. The success of new neurorestorative treatments for damaged brain implies the need to know, with greater accuracy, the mechanisms in charge of regulating adult neurogenesis, both under physiological and pathological conditions. Recent evidence demonstrates that many neurotransmitters, glutamate in particular, control the subventricular zone, thus being part of the complex signalling network that influences the production of new neurons. Conclusion. Neurotransmitters provide a link between brain activity and subventricular zone neurogenesis. Therefore, a deeper knowledge of the role of neurotransmitters systems, such as glutamate and its transporters, in adult neurogenesis, may provide a valuable tool to be used as a neurorestorative therapy in this pathology.Peer Reviewe

The forgotten habitats in conservation: early successional vegetation

Conservation efforts in terrestrial environments have focused on preserving patches of natural habitats and restoring disturbed habitats, with the main goal of transforming them into forests or habitats that resemble the original conditions. This approach tends to overlook the importance of conserving early successional vegetation (e.g., riverside vegetation, natural regeneration, young secondary forests), which often includes a large number of species (e.g., plants and animals) associated with or restricted to these habitats. In this paper we want to bring to attention the importance of preserving early successional vegetation, and to encourage scientists to investigate, e.g., the diversity, distribution, and species interactions occurring in these habitats. To address these goals, we focus on two main objectives: (1) to identify the common types of early successional vegetation in the Costa Rican Central Valley; and (2) to use some case studies to draw attention to the importance that such areas have as reservoirs of a large portion of the diversity unique to early successional stages. We first include an example to show the diversity of plants in small forest patches immersed in a large urbanized area. We provide general information on the insects that occur in early successional vegetation in urban areas, and in further detail examples of butterflies. Additionally, we provide examples of birds and mammals that are restricted to early successional vegetation, and how the reduction of this vegetation type affects species conservation. Finally, we encourage scientists to investigate these early successional habitats, particularly those species exclusive to early successional stages. Special attention should be paid to endemic species and those with a restricted distribution. Information of this type will make conservation of the diversity contained in these habitats possible.Los hábitats olvidados en conservación: la vegetación de estados sucesionales tempranos. Los esfuerzos de conservación en ambientes terrestres se han centrado principalmente en la preservación de ambientes naturales y la restauración de diferentes hábitats, con la meta principal de transformar estos ambientes en bosques maduros o hábitats que asemejen las condiciones originales. Este enfoque tiende a pasar por alto la importancia de conservar la vegetación de estados de regeneración temprana (e.g., vegetación riparia, regeneración natural, bosque secundario joven), la cual incluye un gran número de especies (e.g., plantas y animales) asociadas o restringidas a estos hábitats. Con este artículo queremos llamar la atención sobre la importancia de preservar áreas cubiertas con vegetación de sucesión temprana, e instar a científicos y naturalistas a investigar, e.g., la diversidad, distribución, e interacciones entre las especies presentes en estos ambientes. Para apoyar esta meta, nos enfocamos en dos objetivos principales: (1) identificar los tipos más comunes de vegetación pionera en el Valle Central de Costa Rica; y (2) utilizar algunos casos de estudio para llamar la atención sobre la importancia que tales áreas tienen como reservorio de gran parte de la diversidad, mucha de la cual es única de los estados de sucesión temprana. Primero se incluye un ejemplo particular en el cual se muestra la diversidad de plantas en pequeños fragmentos de bosque y matorral inmersos en una gran área urbanizada. Después se presenta una revisión general de los insectos que habitan en la vegetación de sucesión temprana en áreas urbanas, para luego discutir en mayor detalle ejemplos de mariposas. Además, proporcionamos ejemplos de especies de aves y mamíferos que están restringidos a vegetación de sucesión temprana, y cómo la reducción de este ambiente afecta su conservación. Finalmente, instamos a los científicos de diferentes áreas a investigar los diversos procesos ecológicos e interacciones biológicas inherentes a los estados de regeneración temprana. Especial atención requieren aquellas especies exclusivas o endémicas de estos ambientes. Sin esta información es imposible conservar la diversidad de estos hábitats.UCR::Vicerrectoría de Docencia::Ciencias Básicas::Facultad de Ciencias::Escuela de Biologí

Fertilização orgânica do solo e foliar do milho (Zea mays) no litoral equatoriano: Edaphic and foliar organic fertilization of corn (Zea mays) in the Ecuadorian Littoral

O objetivo desta pesquisa foi avaliar o efeito da fertilização do solo e foliar na cultura do milho. A pesquisa foi realizada nas terras da fazenda "Elvira", de propriedade do Sr. Segundo Murillo Bermeo, localizada na paróquia de Pimocha, Babahoyo. As coordenadas geográficas são 79° 60' de longitude oeste e 01° 83' de latitude sul e uma altitude de 8 metros acima do nível do mar. O solo é argiloso, com drenagem e topografia regulares. O híbrido Somma foi usado como material de plantio. Os tratamentos estudados foram: Bioshield na dose de 1,0 L/ha; Extrato de algas marinhas 1,0 L/ha; Biol 2,0 L/ha; Humus la florida 800 kg/ha; Zeolite 635 kg/ha; Sulpomag 300 kg/ha e Nitrogênio (controle convencional) 70 kg/ha. Foi usado um projeto experimental de bloco completo aleatório, com sete tratamentos e três réplicas. O teste de Tukey a 95% de probabilidade foi usado para comparar as médias. Os dados avaliados foram dias de floração e maturação da espiga, altura da planta, altura de inserção da espiga, comprimento da espiga, número de grãos por espiga, rendimento e análise econômica. A partir dos resultados, foi determinado que os tratamentos que aplicaram fertilização edáfica floresceram e amadureceram em um tempo maior; a maior altura de planta foi obtida com a aplicação de Sulpomag na dose de 300 kg/ha e o uso de Humus la florida na dose de 800 kg/ha superou as médias em termos de altura de inserção da espiga; o maior comprimento de espiga e número de grãos/espiga foi observado no tratamento com Sulpomag na dose de 300 kg/ha e o melhor rendimento foi registrado com Sulpomag na dose de 300 kg/ha

Tracer-aided ecohydrological modelling across climate, land cover, and topographical gradients in the tropics

Funding Information: We thank the Leverhulme Trust funded ISOLAND (RPG‐2018‐375) project, the IAEA‐CRP F31005 contract 22904, the IAEA‐CRP F31006, and the IAEA‐CRP F31006 and UCR C1038 funded the IsoRSM project. We also acknowledge the many suggestions by two anonymous reviewers that improved this paper. Funding Information: We thank the Leverhulme Trust funded ISOLAND (RPG-2018-375) project, the IAEA-CRP F31005 contract 22904, the IAEA-CRP F31006, and the IAEA-CRP F31006 and UCR C1038 funded the IsoRSM project. We also acknowledge the many suggestions by two anonymous reviewers that improved this paper. Publisher Copyright: © 2023 The Authors. Hydrological Processes published by John Wiley & Sons Ltd.Peer reviewedPublisher PD

Divulgación en tiempos de pandemia: el poder de las webs

Trabajo presentado en el simposio Micromundo Aprendizaje-Servicio para el descubrimiento de antibiótico

List of Species as recorded by Canadian and EU Bottom Trawl Surveys in Flemish Cap

A list of species has been prepared with all records in each haul of both Canadian (1977-1985) and EU (1988-2002 and 2003-2012) bottom trawl surveys. Even though sampling intensity and taxonomic interest changed with time, the three periods can be considered almost homogeneous. Main change occurred when the EU survey increased the depth range, from 730 to 1460 meters depth, and all invertebrates were recorded