“Diseño de una cámara de congelación para el almacenamiento de productos cárnicos en el Hotel Baldi Hot Springs durante temporada alta”

Proyecto de Graduación (Licenciatura en Mantenimiento Industrial) Instituto Tecnológico de Costa Rica, Escuela de Ingeniería Electromecánica, 2021El proyecto “Diseño de una cámara de congelación para el almacenamiento de productos cárnicos en el Hotel Baldi Hot Springs durante temporada alta”, se ubica en la Fortuna de San Carlos, Alajuela. El hotel se caracteriza por ofrecer siempre frescos sus productos cárnicos. Previo a la preparación de los platillos en los restaurantes del hotel, los productos cárnicos deben ser almacenado en condiciones que no permitan su degradación; condiciones que se logran mediante sistemas de refrigeración. Esta propuesta consiste en un sistema mecánico de refrigeración por compresión que utilice como sustancia refrigerante el R-507, en los equipos de la cámara frigorífica. El diseño se basó en especificaciones de la norma ASHRAE (2010), la cual incluye las capacidades requeridas por los equipos en función de la carga térmica, la generación de planos constructivos, estimación del costo base del proyecto, distribución y selección de equipos. De lo anterior se determinó la carga térmica en 8.91 TR. Además, de la norma ASHRAE, se encuentran las disposiciones sanitarias que indica la Organización de las Naciones Unidas para la Alimentación y la Agricultura (FAO), disposiciones técnicas del Instituto Nacional de Vivienda y Urbanismos (INVU), Manual de Disposiciones Técnicas generales sobre la seguridad humana y protección contra incendios, utilizado este último por la Unidad de Ingeniería del Benemérito Cuerpo de Bomberos de Costa Rica. Además, para el diseño de la cámara frigorífica se usó el programa SolidWorks para el modelo 3D y la generación de planos constructivos, contemplando las normas y requisitos anteriormente mencionadas. Conjuntamente, se realizó un presupuesto para la puesta en marcha del proyecto, el cual requiere una inversión de $62 192.64 dólares americanos.The project "Freezing machine design, for storing meat products at Hot Springs Hotel during peak season", is located in La Fortuna de San Carlos, Alajuela. The Hotel is characterized by always offering its meat products fresh. Prior to the preparation of the dishes in the Hotel’s restaurant, the meat products must be stored in conditions that do not allow their degradation; conditions obtained through these cooling systems. This proposal consists of a mechanical compression refrigeration system that uses R-507 as a refrigerant substance, used in the cold room equipment. The design was based on specifications from the ASHRAE standard (2010), which includes capacities required by the equipment based on the thermal load, the generation of construction plans, an estimate of the project's base cost, distribution and selection of equipment. From the above, the thermal load was determined at 8.91 TR. In addition to the ASHRAE standard, there are the sanitary provisions indicated by the Food and Agriculture Organization of the United Nations (FAO), technical provisions of the National Institute of Living and Urban Planning (INVU), Manual of General Technical Dispositions on the human safety and fire protection, the latter used by the Engineering Unit of the Meritorious Fire Department of Costa Rica. In addition, for the design of the cold room, the SolidWorks program was used for the 3D model and the generation of construction plans, considering the previous mentioned standards and requirements. Finally, a financial study was done, considering a budget for the start-up of the project, which requires an investment of US$ 62,192.64

Activity-dependent trafficking of lysosomes in dendrites and dendritic spines.

In neurons, lysosomes, which degrade membrane and cytoplasmic components, are thought to primarily reside in somatic and axonal compartments, but there is little understanding of their distribution and function in dendrites. Here, we used conventional and two-photon imaging and electron microscopy to show that lysosomes traffic bidirectionally in dendrites and are present in dendritic spines. We find that lysosome inhibition alters their mobility and also decreases dendritic spine number. Furthermore, perturbing microtubule and actin cytoskeletal dynamics has an inverse relationship on the distribution and motility of lysosomes in dendrites. We also find trafficking of lysosomes is correlated with synaptic α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid-type glutamate receptors. Strikingly, lysosomes traffic to dendritic spines in an activity-dependent manner and can be recruited to individual spines in response to local activation. These data indicate the position of lysosomes is regulated by synaptic activity and thus plays an instructive role in the turnover of synaptic membrane proteins

On the naturalness of Einstein's equation

We compute all 2-covariant tensors naturally constructed from a semiriemannian metric which are divergence-free and have weight greater than -2. As a consequence, it follows a characterization of the Einstein tensor as the only, up to a constant factor, 2-covariant tensor naturally constructed from a semiriemannian metric which is divergence-free and has weight 0 (i.e., is independent of the unit of scale). Since these two conditions are also satisfied by the energy-momentum tensor of a relativistic space-time, we discuss in detail how these theorems lead to the field equation of General Relativity.Comment: 12 pages, added references, corrected typo

Best Available Techniques (BAT) Reference Document for the Production of Chlor-alkali. Industrial Emissions Directive 2010/75/EU (Integrated Pollution Prevention and Control)

The BAT reference document entitled ‘Production of Chlor-alkali’ forms part of a series presenting the results of an exchange of information between EU Member States, the industries concerned, non-governmental organisations promoting environmental protection, and the Commission, to draw up, review and, where necessary, update BAT reference documents as required by Article 13(1) of the Directive 2010/75/EU on industrial emissions. This document is published by the European Commission pursuant to Article 13(6) of the Directive. This BREF for the production of chlor-alkali covers certain industrial activities specified in Sections 4.2(a) and 4.2(c) of Annex I to Directive 2010/75/EU, namely the production of chlor-alkali chemicals (chlorine, hydrogen, potassium hydroxide and sodium hydroxide) by the electrolysis of brine. In particular, this document covers the following processes and activities: - the storage of salt; - the preparation, purification and resaturation of brine; - the electrolysis of brine; - the concentration, purification, storage and handling of sodium/potassium hydroxide; - the cooling, drying, purification, compression, liquefaction, storage and handling of chlorine; - the cooling, purification, compression, storage and handling of hydrogen; - the conversion of mercury cell plants to membrane cell plants; - the decommissioning of mercury cell plants; - the remediation of chlor-alkali production sites. Important issues for the implementation of Directive 2010/75/EU in the chlor-alkali industry are the conversion and decommissioning of mercury cell plants, the conversion of asbestos diaphragm cell plants and the use of non-asbestos diaphragms, electricity consumption, and emissions of chlorine to air and water. The BREF contains seven chapters. Chapters 1 and 2 provide general information on the chlor-alkali industry and on the industrial processes and techniques used within this sector. Chapter 3 provides data and information concerning the environmental performance of installations in terms of current emissions, consumption of raw materials, water and energy, and generation of waste. Chapter 4 describes the techniques to prevent or reduce the environmental impact of installations in the sector. In Chapter 5 the BAT conclusions, as defined in Article 3(12) of the Directive, are presented for the chlor-alkali industry. Chapters 6 and 7 are dedicated to emerging techniques as well as to concluding remarks and recommendations for future work in the sector, respectively.JRC.J.5-Sustainable Production and Consumptio

Stereo Parallel Tracking and Mapping for Robot Localization

This paper describes a visual SLAM system based on stereo cameras and focused on real-time localization for mobile robots. To achieve this, it heavily exploits the parallel nature of the SLAM problem, separating the time-constrained pose estimation from less pressing matters such as map building and refinement tasks. On the other hand, the stereo setting allows to reconstruct a metric 3D map for each frame of stereo images, improving the accuracy of the mapping process with respect to monocular SLAM and avoiding the well-known bootstrapping problem. Also, the real scale of the environment is an essential feature for robots which have to interact with their surrounding workspace. A series of experiments, on-line on a robot as well as off-line with public datasets, are performed to validate the accuracy and real-time performance of the developed method

Patterns of pan-genome occupancy and gene coexpression under water-deficit in Brachypodium distachyon

Natural populations are characterized by abundant genetic diversity driven by a range of different types of mutation. The tractability of sequencing complete genomes has allowed new insights into the variable composition of genomes, summarized as a species pan-genome. These analyses demonstrate that many genes are absent from the first reference genomes, whose analysis dominated the initial years of the genomic era. Our field now turns towards understanding the functional consequence of these highly variable genomes. Here, we analysed weighted gene coexpression networks from leaf transcriptome data for drought response in the purple false brome Brachypodium distachyon and the differential expression of genes putatively involved in adaptation to this stressor. We specifically asked whether genes with variable “occupancy” in the pan-genome – genes which are either present in all studied genotypes or missing in some genotypes – show different distributions among coexpression modules. Coexpression analysis united genes expressed in drought-stressed plants into nine modules covering 72 hub genes (87 hub isoforms), and genes expressed under controlled water conditions into 13 modules, covering 190 hub genes (251 hub isoforms). We find that low occupancy pan-genes are under-represented among several modules, while other modules are over-enriched for low-occupancy pan-genes. We also provide new insight into the regulation of drought response in B. distachyon, specifically identifying one module with an apparent role in primary metabolism that is strongly responsive to drought. Our work shows the power of integrating pan-genomic analysis with transcriptomic data using factorial experiments to understand the functional genomics of environmental respons

New directions for the treatment of adrenal insufficiency

The following funding bodies supported this work: Biotechnology and Biological Sciences Research Council (BBSRC BB/L00267/1, to LG), Rosetrees Trust (to LG), Barts and The London Charity (417/2235, to LG), EU COFUND (PCOFUND-GA-2013-608765, to LG and GRB). IH is supported by a Medical Research Council (MRC, G0802796) PhD studentship

Subretinal delivery of adeno-associated virus serotype 2 results in minimal immune responses that allow repeat vector administration in immunocompetent mice

Background: Adeno-associated virus serotype 2 (AAV2) vectors show considerable promise for ocular gene transfer. However, one potential barrier to efficacious long-term therapy is the development of immune responses against the vector or transgene product. Methods: We evaluated cellular and humoural responses in mice following both single and repeated subretinal administration of AAV2, and examined their effects on RPE65 and green fluorescent protein transgene expression. Results: Following subretinal administration of vector, splenocytes and T-cells from draining lymph nodes showed minimal activation following stimulation by co-culture with AAV2. Neutralizing antibodies (NAbs) were not detected in the ocular fluids of any mice receiving AAV2 or in the serum of mice receiving a lower dose. NAbs were present in the serum of a proportion of mice receiving a higher dose of the vector. Furthermore, no differences in immunoglobulin titre in serum or ocular fluids against RPE65 protein or AAV2 capsid between treated and control mice were detected. Histological examination showed no evidence of retinal toxicity or leukocyte infiltration compared to uninjected eyes. Repeat administration of low-dose AAV.hRPE65.hRPE65 to both eyes of RPE65-/- mice resulted in transgene expression and functional rescue, but re-administration of high-dose AAV2 resulted in boosted NAb titres and variable transgene expression in the second injected eye. Conclusions: These data, which were obtained in mice, suggest that, following subretinal injection, immune responses to AAV2 are dose-dependent. Low-dose AAV2 is well tolerated in the eye, with minimal immune responses, and transgene expression after repeat administration of vector is achievable. Higher doses lead to the expression of NAbs that reduce the efficacy of repeated vector administration

Best Available Techniques (BAT) Reference Document for the Production of Large Volume Organic Chemicals. Industrial Emissions Directive 2010/75/EU (Integrated Pollution Prevention and Control)

The Best Available Techniques (BAT) Reference Document (BREF) for the Production of Large Volume Organic Chemicals is part of series of documents presenting the results of an exchange of information between EU Member States, the industries concerned, non-governmental organisations promoting environmental protection, and the Commission, to draw up, review and – where necessary – update BAT reference documents as required by Article 13(1) of Directive 2010/78/EU on Industrial Emissions (the Directive). This document is published by the European Commission pursuant to Article 13(6) of the Directive. The BREF for the production of Large Volume Organic Chemicals concerns the production of the following organic chemicals, as specified in Section 4.1 of Annex I to Directive 2010/75/EU: a. simple hydrocarbons (linear or cyclic, saturated or unsaturated, aliphatic or aromatic); b. oxygen-containing hydrocarbons such as alcohols, aldehydes, ketones, carboxylic acids, esters and mixtures of esters, acetates, ethers, peroxides and epoxy resins; c. sulphurous hydrocarbons; d. nitrogenous hydrocarbons such as amines, amides, nitrous compounds, nitro compounds or nitrate compounds, nitriles, cyanates, isocyanates; e. phosphorus-containing hydrocarbons; f. halogenic hydrocarbons; g. organometallic compounds; k. surface-active agents and surfactants. This document also covers the production of hydrogen peroxide as specified in Section 4.2 (e) of Annex I to Directive 2010/75/EU; and the combustion of fuels in process furnaces/heaters, where this is part of the abovementioned activities. The production of the aforementioned chemicals is covered by this document when it is done in continuous processes where the total production capacity of those chemicals exceeds 20 kt/yr. While the main aim of the LVOC BREF is to facilitate reduction of emissions from chemical processes, other environmental issues - like energy efficiency, resource efficiency, wastes and residues - are also covered. This BREF contains 14 Chapters. Chapters 1 and 2 provide general information on the Large Volume Organics industrial sector and on generic industrial production processes used in this sector. Chapters 3 to 12 provide general information , applied processes and techniques, current emission and consumption levels, techniques to consider in determination of BAT and emerging techniques for various illustrative processes: lower olefins, aromatics, ethylbenzene and styrene, formaldehyde, ethylene oxide and ethylene glycols, phenol, ethanolamines, toluene diisocyanate and methylene diphenyl diisocyanate, ethylene dichloride and vinyl chloride monomer and hydrogen peroxide. Chapter 13 presents BAT conclusions as defined in Article 3(12) of the Directive. Concluding remarks and recommendations for future work are presented in Chapter 14.JRC.B.5-Circular Economy and Industrial Leadershi

Altered thiol chemistry in human amyotrophic lateral sclerosis-linked mutants of superoxide dismutase 1

Neurodegenerative diseases share a common characteristic, the presence of intracellular or extracellular deposits of protein aggregates in nervous tissues. Amyotrophic Lateral Sclerosis (ALS) is a severe and fatal neurodegenerative disorder, which affects preferentially motoneurons. Changes in the redox state of superoxide dismutase 1 (SOD1) are associated with the onset and development of familial forms of ALS. In human SOD1 (hSOD1), a conserved disulfide bond and two free cysteine residues can engage in anomalous thiol/disulfide exchange resulting in non-native disulfides, a hallmark of ALS that is related to protein misfolding and aggregation. Because of the many competing reaction pathways, traditional bulk techniques fall short at quantifying individual thiol/disulfide exchange reactions. Here, we adapt recently developed single-bond chemistry techniques to study individual disulfide isomerization reactions in hSOD1. Mechanical unfolding of hSOD1 leads to the formation of a polypeptide loop held by the disulfide. This loop behaves as a molecular jump rope that brings reactive Cys-111 close to the disulfide. Using force-clamp spectroscopy, we monitor nucleophilic attack of Cys-111 at either sulfur of the disulfide and determine the selectivity of the reaction. Disease-causing mutations G93A and A4V show greatly altered reactivity patterns, which may contribute to the progression of familial ALS