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  • Miniatura
    Item type: Artículo ,
    Macroscopic modelling and parameter estimation of blueberries freeze-drying
    (Institution of Chemical Engineers, 2025-07)
    Schenck, S.
    ;
    Barrios, S.
    ;
    Ferrari, A.
    ;
    Lema, P.
    ;
    Goñi, Sandro Mauricio
    This work aimed to enhance comprehension of the processes involved in the primary stage of blueberry freeze-drying by applying and evaluating two mathematical models to whole fruits, assuming spherical geometry. This approach represents a novel contribution to the modeling of whole solid plant foods. Blueberries were modeled as spheres with dried and icy layers delimited by the icy core radius. Two models were proposed, to predict the evolution of key state variables - interface temperature, internal temperature, interface pressure, surface pressure and total sublimation time during the process. Model 1 includes five parameters and a detailed representation of heat and mass transfer resistances, and assumes spherical symmetry, neglects shrinkage and desorption, and describes a one-dimensional heat and mass transfer in series. Model 2 is a simplified version of Model 1, represented with three parameters, by unifying mass and heat transfer coefficients. Experimental data from pressure rise tests (PRT) at 20 Pa chamber pressure (P_vc) and shelf temperatures (T_s) of -20, 0, 10 and 20 °C were used for parameter estimation and validation. Particle swarm optimization was employed to determine heat and mass transfer parameters by minimizing mean square error (MSE) and mean absolute percentage error (MAPE). Performance metrics including MSE, MAPE and coefficient of determination (R^2) were considered to evaluate the models. The two models achieved errors below 10% for PRT. Skin appears to dominate overall mass transfer resistance. When models were used to predict sublimation rate, Model 2 significantly outperformed Model 1 in predicting the initial slope of PRT curves (R^2 = 0.96 vs. 0.73). Model 2 was used to simulate the effects of control variables (P_vc and T_s) and blueberry initial radius on sublimation time. This work enhances the understanding of heat and mass transfer mechanisms in blueberry freeze-drying, providing a valuable tool for process optimization.
  • Miniatura
    Item type: Artículo ,
    Core data set para la generación de datos de la vida real en esclerosis múltiple: adaptación de una iniciativa global para América Latina
    (Revista de Neurologia, 2024-04)
    Rojas, Juan Ignacio
    ;
    Gracia, Fernando
    ;
    Parciak, Tina
    ;
    Alonso, Ricardo
    ;
    Becker, Jefferson
    Introduction: The primary objective of the core data set is to reduce heterogeneity and promote harmonization among data sources in EM, thereby reducing the time needed to execute real life data collection efforts. Recently, a group led by the Multiple Sclerosis Data Alliance has developed a core data set for collecting real-world data on multiple sclerosis (MS) globally. Our objective was to adapt this global data set to the needs of Latin America, so that it can be implemented by the registries already developed and in the process of development in the region.Material and methods: A working group was formed regionally, the core data set created globally was adapted (translation process into Spanish, incorporation of regional variables and consensus on variables to be used). Consensus was obtained through the remote Delphi methodology of a round of questionnaires and remote discussion of the core data set variables.Results: A total of 25 professionals from Latin America carried out the adaptation process between November 2022 and July 2023. Agreement was established on a core data set of nine categories and 45 variables, version 2023 to suggest its implementation in developed or developing registries, and MS cohorts in the region.Conclusion: The core data set seeks to harmonize the variables collected by registries and cohorts in MS in Latin America in order to facilitate said collection and allow collaboration between sources. Its implementation will facilitate real life data collection and collaboration in the region.
  • Miniatura
    Item type: Artículo ,
    Lymphoid Peritoneal Fluid as a Variant of Chylous-Like Effluent in Peritoneal Dialysis: Proposal for a New Diagnostic Term
    (Italian Society of Nephrology, 2025-04)
    Fernandez Carlos, Nigel
    ;
    Ocampo, Maria Laura
    ;
    Musso, Carlos Guido
    ;
    Cristiano, Fabrizio
    ;
    Aroca Martinez, Gustavo
    The cloudy bag in peritoneal dialysis is generally associated with infectious peritonitis and non-infectious etiologies. These cloudy bags may have increased cellularity or low/acellular counts. In the case of low cell count, the concomitant detection of fibrin or fat can provide guidance on its etiology. The cloudy peritoneal bag with a whitish appearance is usually due to its high fat content (chyloperitoneum). The etiologies include pharmacological, traumatic or inflammatory causes. The elevated fatty component in chyloperitoneum may be triglycerides (chylous), cholesterol (pseudochylous) or lymph. We present the case of a patient with stage 5 chronic kidney disease (CKD). He starts continuous ambulatory peritoneal dialysis and presents turbid but acellular peritoneal effluent with chylous appearance, negative cultures, and low levels of triglycerides and cholesterol on physicochemical evaluation. It doesn´t meet the criteria for chylous or pseudochylous fluid, which is why the term lymphoid fluid is here proposed to describe it, because of its resemblance to lymphatic fluid in color. To our knowledge, this is the first case in the literature to report this effluent (milky-looking fluid without high levels of triglycerides or cholesterol) and to propose a specific term to describe it.
  • Miniatura
    Item type: Artículo ,
    Resilience of the sea urchin Arbacia dufresnii to a shrimp wastewater spill: Recovery after a disease outbreak
    (Elsevier, 2025-05)
    Crespi Abril, Augusto Cesar
    ;
    Rubilar Panasiuk, Cynthia Tamara
    In the summer of 2023, Arbacia dufresnii populations in Golfo Nuevo, Patagonia, faced a significant environmental stressor due to a wastewater spill from local fishing industry operations. This study explores the resilience of sea urchins to this stressor and their recovery following a disease outbreak linked to the spill. Prior to the spill, sea urchin densities varied across different sites with no signs of infection. However, following the spill, over 90 % of the sea urchins at the affected site exhibited symptoms such as severe epidermal damage and bacterial infections. Remarkably, within less than a year, the populations demonstrated considerable resilience; disease rates plummeted, and population density returned to pre-spill levels without significant changes in size distribution. This recovery, primarily through the migration of mature individuals rather than juvenile recruitment, underscores the profound impact of chemical pollutants in triggering marine diseases. Furthermore, this study serves as a significant example of how population density and health estimates can be effectively conducted through a non-lethal research approach, adhering to ethical standards, and ensuring the well-being of the sea urchins. These findings highlight the necessity of continuous environmental monitoring to effectively manage and mitigate the impacts of such stressors.
  • Miniatura
    Item type: Artículo ,
    Spatiotemporal faunal connectivity across global sea floors
    (Nature Publishing Group, 2025-07)
    O'Hara, Timothy D.
    ;
    Hugall, Andrew F.
    ;
    Haines, Margaret L.
    ;
    Weber, Alexandra A. T.
    ;
    Eichsteller, Angelina
    Our knowledge of biogeographic patterns and processes in the deep sea has been limited by the lack of integrated datasets that cover its vast extent1. Here we analyse a new global dataset of genomic DNA sequences, spanning an entire taxonomic class of benthic invertebrates (Ophiuroidea), to obtain a broad understanding of phylogenetic divergence and biotic movement across all oceans, from coastal margins down to the abyssal plains. We show that regional faunas on the continental shelf are phylogenetically divergent, particularly at temperate and tropical latitudes. By contrast, assemblages in the deep sea are much more connected. Many temperate deep-sea lineages have achieved distribution ranges across the planet, including over the Quaternary period. A close relationship exists between deep-sea faunas of the northern Atlantic and, on the opposite side of the globe, southern Australia. Bathymetric interchange is not only reliant on vertical migration through isothermal polar waters but also occurs across the thermal depth gradients of tropical regions. The connected nature of deep-sea life should be an important consideration in marine conservation assessments.