Resumo Um experimento de parcelas subdivididas foi conduzido em um delineamento de blocos completos casualizados com três repetições em dois anos de cultivo no Mazandaran Rice Research Institute para estudar os regimes de cultivo e irrigação. O principal fator são os regimes de irrigação em três níveis, irrigação permanente ao longo do dia (T1), irrigação dois dias após o desaparecimento da água do solo (T2) e saturação permanente do solo (T3); o segundo fator são os métodos de cultivo em três níveis: cultivo sem arado (W1), empilhar 60 cm (W2) e empilhar 80 cm (W3). Com base nos resultados obtidos na análise combinada, o efeito do ano foi significativo em termos de precipitação pluviométrica, produtividade 2, número de perfilhos, número de grãos vazios, peso de 1.000 grãos, porcentagem de grãos triturados e rendimento de arroz branco. O efeito do fator principal foi significativo para todas as características, exceto produtividade 1 e altura de planta. Com base nos resultados da comparação do efeito médio ano x tratamento, quatro tratamentos, sem aração com irrigação permanente ao longo do dia no primeiro e segundo ano do experimento, cultivo sem aração com irrigação dois dias após o desaparecimento da água do solo no segundo ano de experimento e cultivo sem aração com irrigação saturada permanente no primeiro e segundo ano do experimento, foi identificado em termos de produtividade de grãos como métodos de plantio adequados com regimes de irrigação adequados. Com base nos resultados obtidos na visão poligonal em diferentes anos do experimento, os tratamentos T3W1, T3W2 e T1W1 podem ser sugeridos como tratamentos desejáveis em termos de regimes de irrigação e métodos de cultivo nessa cultivar de arroz. De acordo com o diagrama de classificação dos tratamentos baseados em características nos anos de experimentação, T1W1, T2W2 e T1W3 foram introduzidos como os tratamentos mais desejáveis para o cultivo dessa cultivar de arroz.

Abstract A split-plot experiment was conducted in a randomized complete block design with three replications in two cropping years at Mazandaran Rice Research Institute to study cultivation and irrigation regimes. The main factor is three-level irrigation regimes, permanent irrigation throughout the day (T1), irrigation two days after water disappears from the soil (T2) and permanent soil saturation (T3) the second factor is three-level cultivation methods., Plowless cultivation (W1), stack 60 cm (W2), and stack 80 cm (W3). Based on the results obtained from the combined analysis, the effect of the year was significant in terms of rainfall, productivity 2, number of tillers, number of empty grains, 1000-grain weight, percentage of the crushed grain, and white rice yield. The effect of the main factor was significant for all traits except productivity 1 and plant height. Based on the results of comparing the mean effect of year × treatment, four treatments, without plowing with permanent irrigation throughout the day in the first and second year of the experiment, cultivation without plowing with irrigation two days after water disappears from the soil in the second year of experiment and cultivation without Plowing with permanent saturated irrigation in the first and second years of the experiment was identified in terms of grain yield as suitable planting methods with appropriate irrigation regimes. Based on the results obtained from the polygon view in different years of the experiment, T3W1, T3W2, and T1W1 treatments can be suggested as desirable treatments in terms of irrigation regimes and cultivation methods in this rice cultivar. According to the ranking diagram of treatments based on traits in the years of experimentation, T1W1, T2W2 and T1W3 were introduced as the most desirable treatments for cultivating this rice cultivar.

Resumo O processo de manufatura aditiva a arco arame ou WAAM (Wire Additive Arc Welding) é reconhecido como um processo capaz de confeccionar peças de elevada complexidade geométrica, com propriedades mecânicas comparáveis às do material fundido. Entretanto, existem desafios significativos associados ao WAAM, como microestruturas e propriedades mecânicas indesejáveis, elevadas tensões residuais e distorção geométrica. Este estudo visa contribuir com a seleção de parâmetros de deposição do aço VP50IM utilizando WAAM via TIG (Tungsten Inert Gas) pulsado e caracterização do empilhamento gerado, utilizando a metodologia Central Composto Completo, CCC. Neste estudo variou-se a corrente de pico (Cp) e de base (Cb), velocidade de alimentação de arame durante pico (Vap), base (Vab) e velocidade de soldagem (Vs). O parâmetro ideal apresentado foi Cp=200A, Cb=100A, Vap=2,9cm/min, Vab=1,2cm/min e Vs=20cm/min. Ensaios de tração mostraram uma resistência até 15% maior nas amostras na seção longitudinal ao sentido de soldagem em comparação ao sentido transversal. Ensaios de dureza demonstraram uma dureza até 9% menor no centro do empilhamento em comparação ao topo e base. A análise de fratura dos corpos de prova evidenciou fratura dúctil. Wire Welding geométrica fundido Entretanto indesejáveis VPIM VP IM Tungsten Gas gerado Completo CCC variouse variou se Cp (Cp Cb, Cb , (Cb) Vap, Vap (Vap) Vab (Vab Vs. Vs . (Vs) Cp200A CpA 200A Cp=200A Cb100A CbA 100A Cb=100A Vap29cmmin Vapcmmin 2 9cm min cm Vap=2,9cm/min Vab12cmmin Vabcmmin 1 2cm Vs20cmmin Vscmmin 20cm Vs=20cm/min 15 transversal 9 dúctil (Cb (Vap (Vs cmmin

Abstract The wire arc additive manufacturing process or WAAM (Wire Additive Arc Welding) is recognized as a process able of making pieces of high geometric complexity, with mechanical properties comparable to those of the cast material. However, there are significant challenges associated with WAAM, such as undesirable microstructures and mechanical properties, high residual stresses and geometric distortion. This study aims to contribute to the selection of deposition parameters for VP50IM steel using WAAM via pulsed TIG (Tungsten Inert Gas) and characterization of the generated stacking, using the Central Composite Complete methodology, CCC. In this study, the peak (Cp) and base (Cb) current, wire feed speed during peak (Vap), base (Vab) and welding speed (Vs) were varied. The ideal parameter presented was Cp=200A, Cb=100A, Vap=2.9cm/min, Vab=1.2cm/min and Vs=20cm/min. Tensile tests showed up to 15% greater resistance in the samples in the longitudinal section in the welding direction compared to the transverse direction. Hardness tests demonstrated up to 9% less hardness at the center of the stack compared to the top and bottom. The fracture analysis of the specimens showed ductile fracture. Wire Welding complexity material However distortion VPIM VP IM Tungsten Gas stacking methodology CCC Cp (Cp Cb (Cb current Vap, Vap , (Vap) Vab (Vab Vs (Vs varied Cp200A CpA 200A A Cp=200A Cb100A CbA 100A Cb=100A Vap29cmmin Vapcmmin 2 9cm min cm Vap=2.9cm/min Vab12cmmin Vabcmmin 1 2cm Vs20cmmin Vscmmin 20cm Vs=20cm/min 15 9 bottom (Vap cmmin

RESUMO Contexto: O câncer colorretal é uma das patologias mais prevalentes em todo o mundo, cujo prognóstico está ligado à detecção precoce. A colonoscopia é o padrão ouro para triagem, e o diagnóstico geralmente é feito histologicamente a partir de biópsias. Visando reduzir o tempo de inspeção e diagnóstico, bem como as biópsias e recursos envolvidos, outras técnicas estão sendo promovidas para realizar avaliações precisas de colonoscopia in vivo. A biópsia óptica visa detectar tecidos normais e neoplásicos analisando o espectro de autofluorescência com base nas mudanças na distribuição e concentração de moléculas autofluorescentes causadas pelo câncer colorretal. Portanto, a contribuição da autofluorescência analisada por técnicas de processamento de imagem poderia ser uma abordagem para uma caracterização mais rápida do tecido-alvo. Objetivo: Quantificar parâmetros de intensidade por meio do processamento digital de dois conjuntos de dados de imagens de microscopia de autofluorescência em campo amplo tridimensionais, adquiridas por amostras de tecido fresco de cólon de um modelo murino de câncer colorretal. Adicionalmente, analisar os dados de autofluorescência para fornecer uma caracterização em um volume de aproximadamente 50 µm da mucosa do cólon para cada imagem, na segunda (2ª), quarta (4ª) e oitava (8ª) semanas após a indução do câncer colorretal. Método: Desenvolvimento de um modelo murino de câncer colorretal usando indução de azoximetano/sulfato de sódio dextrano, e aquisição de conjuntos de dados de imagens Z-stack por microscopia de autofluorescência em campo amplo, de animais controle e induzidos ao câncer colorretal. Etapas de pré-processamento de ajustes de valores de intensidade seguidas por procedimentos de quantificação e caracterização usando automação de fluxo de trabalho de processamento de imagem por macros do Fiji, e análise estatística de dados. Resultados: A eficácia do modelo de indução de câncer colorretal foi corroborada por uma avaliação histológica para correlacionar e validar a ligação entre as mudanças histológicas e de autofluorescência. A metodologia de processamento digital de imagem proposta foi então realizada nas imagens tridimensionais de camundongos controle e das 2ª, 4ª e 8ª semanas após a indução química do câncer colorretal, para cada conjunto de dados. Análises estatísticas encontraram diferenças significativas nos parâmetros médios, desvio padrão e mínimos entre amostras de controle e aquelas da 2ª semana após a indução em relação à 4ª semana do primeiro estudo experimental. Isso sugere que as características do câncer colorretal podem ser detectadas após a 2ª semana pós-indução. Conclusão: O uso de autofluorescência ainda apresenta níveis de variabilidade que impedem uma maior sistematização dos dados obtidos durante a progressão do câncer colorretal. No entanto, esses resultados preliminares podem ser considerados uma abordagem para a caracterização tridimensional da autofluorescência do tecido colorretal, descrevendo as características de autofluorescência de amostras que vão da displasia ao câncer colorretal. Contexto mundo precoce triagem envolvidos vivo Portanto tecidoalvo. tecidoalvo alvo. alvo tecido-alvo Objetivo Adicionalmente 5 ª , (2ª) (4ª (8ª Método azoximetanosulfato azoximetano sulfato dextrano Zstack Z stack préprocessamento pré Fiji Resultados médios experimental pósindução. pósindução pós indução. pós-indução Conclusão entanto (2ª

ABSTRACT Background: Colorectal cancer is one of the most prevalent pathologies worldwide whose prognosis is linked to early detection. Colonoscopy is the gold standard for screening, and diagnosis is usually made histologically from biopsies. Aiming to reduce the inspection and diagnostic time as well as the biopsies and resources involved, other techniques are being promoted to conduct accurate in vivo colonoscopy assessments. Optical biopsy aims to detect normal and neoplastic tissues analysing the autofluorescence spectrum based on the changes in the distribution and concentration of autofluorescent molecules caused by colorectal cancer. Therefore, the autofluorescence contribution analysed by image processing techniques could be an approach to a faster characterization of the target tissue. Objective: Quantify intensity parameters through digital processing of two data sets of three-dimensional widefield autofluorescence microscopy images, acquired by fresh colon tissue samples from a colorectal cancer murine model. Additionally, analyse the autofluorescence data to provide a characterization over a volume of approximately 50 µm of the colon mucosa for each image, at second (2nd), fourth (4th) and eighth (8th) weeks after colorectal cancer induction. Methods: Development of a colorectal cancer murine model using azoxymethane/dextran sodium sulphate induction, and data sets acquisition of Z-stack images by widefield autofluorescence microscopy, from control and colorectal cancer induced animals. Pre-processing steps of intensity value adjustments followed by quantification and characterization procedures using image processing workflow automation by Fiji’s macros, and statistical data analysis. Results: The effectiveness of the colorectal cancer induction model was corroborated by a histological assessment to correlate and validate the link between histological and autofluorescence changes. The image digital processing methodology proposed was then performed on the three-dimensional images from control mice and from the 2nd, 4th, and 8th weeks after colorectal cancer chemical induction, for each data set. Statistical analyses found significant differences in the mean, standard deviation, and minimum parameters between control samples and those of the 2nd week after induction with respect to the 4th week of the first experimental study. This suggests that the characteristics of colorectal cancer can be detected after the 2nd week post-induction. Conclusion: The use of autofluorescence still exhibits levels of variability that prevent greater systematization of the data obtained during the progression of colorectal cancer. However, these preliminary outcomes could be considered an approach to the three-dimensional characterization of the autofluorescence of colorectal tissue, describing the autofluorescence features of samples coming from dysplasia to colorectal cancer. Background detection screening involved assessments Therefore Objective threedimensional three dimensional Additionally 5 nd , (2nd) th (4th (8th Methods azoxymethanedextran azoxymethane dextran Zstack Z stack animals Preprocessing Pre Fijis Fiji s macros analysis Results set mean deviation study postinduction. postinduction post post-induction Conclusion However (2nd

The static equilibrium of cylindrical wood pieces in a close-packed order is analyzed. By considering the coefficient of static friction μ L between two adjacent logs and the coefficient of static friction μ G between the logs and the ground, it is demonstrated that the more stringent condition for static equilibrium arises from μ L. This holds true for both systems comprising three logs and those with six logs. The value of the lower threshold μ ~ L for equilibrium is greater for a system with six logs compared to three logs. This problem could serve as a study project in Newtonian mechanics for first-year college students or for advanced high-school physics students. closepacked close packed analyzed ground firstyear first year highschool high school

Abstract Ring shape microstrip antenna designs supported via an altered ground plane profile are proposed for multi-band response with wider bandwidth in each band. The impedance bandwidth of a single ring patch supported via a slot cut ground plane on a substrate having a thickness of ~ 0.1λg, is 45.8% and the broadside gain is 5.6 dBi. By employing additional stack patches, dual and triple-band configurations are obtained. In the respective operative frequency bands, maximum 15% of bandwidth is achieved in the suggested antenna, with a maximum broadside gain of more than 5.5 dBi. Through the acquired antenna features, the proposed configuration fulfills the criteria of E-GSM900/Secondary Surveillance Radar/Aeronautical Radio Navigation Applications. multiband multi band 01λg λg 0 1λg 0.1λg 458 45 8 45.8 56 5 6 5. dBi patches tripleband triple obtained bands 15 55 features EGSM900/Secondary EGSM900Secondary EGSMSecondary E GSM900/Secondary GSM900 Secondary GSM RadarAeronautical Radar Aeronautical Applications 4 45. 1 EGSM900 EGSM GSM900Secondary GSMSecondary GSM90 EGSM90 GSM9 EGSM9

Abstract. Recent years have marked a huge increase in worldwide efforts to improve the design and manufacture of miniaturized low- and high- power Polymer Electrolyte Membrane Fuel Cells (PEMFCs) for diverse electronic applications, ranging from stationary backup power to mobile transportation, and even as energy sources for a new generation of drone and hybrid vehicular transportation technologies. This communication compiles recent contributions developed by our group of researchers who has worked in the synthesis and characterization of Pt-based catalysts for oxygen reduction reaction (ORR) and in to address the performance and durability of H2/O2 PEMFC - Li Ion batteries in an electric vehicular transport prototype. We will provide an overview of our current contributions in the design, manufacturing, and development of low temperature, high-energy H2/O2 fuel cells which generated electricity is storage in a set of Li-Ion batteries for a vehicular transport prototype, Cinvestav-Sicarú, with more than an hour and thirty minutes of autonomy.

Resumen. Los últimos años han marcado un aumento sustancial en los esfuerzos mundiales para mejorar el diseño y la fabricación de celdas de combustible de membrana de electrolito de polímero (PEMFC) miniaturizadas de baja y alta potencia para diversas aplicaciones electrónicas, que van desde energía de respaldo estacionaria hasta transporte móvil, e incluso como energía. Fuentes para una nueva generación de tecnologías de transporte de drones y vehículos híbridos. Este trabajo recopila contribuciones recientes desarrolladas por nuestro grupo de investigación que ha trabajado en la síntesis y caracterización de catalizadores basados en Pt para la reacción de reducción de oxígeno (ORR) y para abordar el rendimiento y la durabilidad de una celda de combustible H2/O2 -banco de baterías de Iones de litio en un prototipo de transporte vehicular eléctrico. Proporcionaremos una descripción general de nuestros desarrollos actuales en el diseño, fabricación y desarrollo de celdas de combustible H2/O2 de alta energía y baja temperatura que generan electricidad y se almacenan en un conjunto de baterías de iones de litio para un prototipo de transporte vehicular, con más de una hora y media de autonomía.

Abstract Graphene oxide (GO) is one of the main precursors for the production of graphene and other graphene-based materials. We report a simple, safe, and fast synthesis method to obtain graphene oxide as a functional material for battery-type electrodes. Washing and lyophilization processes were performed to evaluate their effects on exfoliation and removal of functional groups from graphene sheets. Sample GO1 consisted of a 10-layer stack of oxidized graphene, while sample GO2 had 8 stacked layers. The difference between them was an extra washing and lyophilization process in the GO2 sample. The electrochemical performance of graphene oxide-based electrodes, classified as battery-type, indicated an improved specific capacity of 10.15 C.g-1 for GO1 against 4.55 C.g-1 for GO2 at a specific current of 0.5 A.g-1. This superior battery-type behavior of the GO1 electrode, also confirmed by electrochemical impedance spectroscopy, was most likely due to a higher degree of oxygenated groups on its surface, as shown by energy dispersive spectroscopy (EDS) and Fourier transform infrared spectroscopy (FTIR) studies. GO (GO graphenebased based materials simple safe batterytype battery type electrodes sheets 10layer layer 10 layers oxidebased batterytype, type, 1015 15 10.1 C.g1 Cg1 Cg C.g 1 C g C.g- 455 4 55 4.5 05 0 5 0. A.g1. Ag1 Ag A.g 1. A A.g-1 electrode surface EDS (EDS FTIR (FTIR studies 101 10. g1 45 4. A.g1 A.g-

Abstract: Massive amounts of data are generated every day from all kinds of sources, from numerical data generated by sensors to veiled messages on social networks. Transforming these data into properly organized pieces of information and transforming it into resources for decision-making is complicated, not only because of the speed and volume at which it is produced, but due to the fact the high complexity of the context in which it is generated. Often, the first step in analyzing the data is to separate it into categories that correspond to segments of interest in that context. However, in many real cases, the limits of these segments and even the number of existing segments is unknown. Clustering techniques allow defining the classes of entities in a data set with sufficient relevance. However, those techniques usually work only with numerical data. Surveys are a very useful tool for collecting data in ill-defined contexts, but these data usually contain values that are not only numerical but of a very diverse nature. This paper presents a modification to the Isodata method to process data with mixed numerical and categorical values. The resulting algorithm is tested by analyzing the results of the 2021 Stack Overflow developer survey. The results obtained in the clustering of such data are sound and show that the Isodata method, with the proposed adaptations, can be successfully employed to discover patterns in complex mixed data.

Abstract In this paper, the hybrid differential evolution and symbiotic organism search (HDS), is the first-time developed for general solutions of a piezoelectric stack in ultrasonic transducers. The convergence and reliability of the new algorithm are verified through comparison with corresponding data from similar previous publications and differential evolution (DE) algorithm. This study also presents and discusses the calculation results using HDS for commercial piezoelectric stacks. The Matlab HDS programs for a segmented piezoelectric (PZT) model have advanced features including its applicability to any configurations, thickness and arbitrary layer numbers of PZT. Using the novel proposed technique, there is no requirement for initial data guess, no limitations for piezoelectric stacks and the convergence rate is much faster than DE. Therefore, the HDS is promising for direct evaluation of specific aging or degradation mechanisms of ultrasonic transducers. paper HDS, , (HDS) firsttime first time transducers DE (DE PZT (PZT configurations technique guess Therefore (HDS

Abstract Innovation on new materials is strongly associated with different techniques and technological developments used on the growth and characterization of samples. Recent studies suggest that one could increase the preferable orientation of the crystals, while they are being formed on the substance, by applying a strong magnetic field. Uncertainty on the magnetic field magnitude, time of exposure, and temperature requirements, impose a challenge from the technological perspective. An upper boundary of 10 T provides a wide enough range for researching the material’s growth. In this work, we present a preliminary design of a 7 Tesla superconducting solenoid. The solenoid uses NbTi cable-in-conduit technology for the windings. The proposed geometry incorporates an experimentation chamber, thermally isolated from the cryogenic solenoid windings, for magnetic stimulation of samples. The sample could be exposed to a temperature gradient ranging from ambient temperature to 200 C, as required by some substrates. We applied an optimization process to reduce the required superconductor and expand the magnetics field uniform from 3 cm wide x 3.5 cm high to a region 3 cm wide and 10 cm tall, large enough to stack their samples vertically. A magnetic force study assisted in determining the election materials for the support structures.

Resumen Para mejorar la calidad de las aplicaciones web, es necesario implementar estrategias de pruebas automatizadas que permitan evaluar integralmente los atributos de funcionalidad y desempeño, los cuales se ven directamente afectados por el comportamiento del hardware de los servidores donde están alojadas. Así como los equipos de IT monitorean la infraestructura que soporta las aplicaciones, las automatizaciones deberían apoyarse en plataformas de monitoreo con analíticas especializadas de pruebas de software. Este artículo presenta la evaluación de cuatro pilas tecnológicas, lo cual permitirá seleccionar la más adecuada para incluirla en el desarrollo de una plataforma especializada en analíticas de calidad de software. Las cuatro pilas de este estudio son: PALG, TICK, ELK, AM. Este artículo explicará las características y diferencias de las pilas frente a diversos componentes como: base de datos, filtrado de información, recolección de métricas del sistema operativo, sistema de alertas, ingesta y visualización de datos. Luego se describen simulaciones y pruebas realizadas sobre cada una de ellas para evaluar sus capacidades. Finalmente se emiten unas conclusiones que permitirán seleccionar la pila tecnológica que será utilizada en el desarrollo de la plataforma de monitoreo o sistema de analíticas especializadas para soportar la realización de pruebas de software a las aplicaciones.

Abstract To rapidly improve the quality of web applications, it is necessary to implement automated testing strategies that allow you to comprehensively evaluate functionality and performance attributes, which are directly affected by the behavior of the hardware of the servers where they are hosted. Just as IT teams monitor the infrastructure that supports the applications, automations should be supported by monitoring platforms with specialized software testing analytics. This article presents the evaluation of four technology stacks, which will make it possible to select the most appropriate one to be included in the development of a platform specialized in software quality analytics. The four stacks in this study are: PALG, TICK, ELK, AM. This article will explain the characteristics and differences of stacks compared to various components such as: database, information filtering, collection of operating system metrics, alert system, data ingestion and visualization. Then simulations and tests carried out on each of them are described to evaluate their capabilities. Finally, conclusions are issued that will allow to select the technology stack that will be used in the development of the system specialized analytics for software testing.

Abstract We study the electronic, the optical and the transport properties of both bulk materials ErN and Er0.125Ga0.875N, which crystallize in zinc-blind and wurtzite structures, respectively, and are utilized in quantum well devices. The properties are calculated using density functional theory (DFT), by applying the full-potential linearized augmented plane-wave (FP-LAPW) method with a spin-orbit coupling effect. The analysis of the electronic properties shows that ErN and Er0.125Ga0.875N have a band gap at 0.79 and 3.38 eV, respectively. On the other hand, the technology makes it possible to stack these materials for a quantum well heterostructure of Er0.125Ga0.875N/ErN. The optical properties such as optical coefficients, refractive index and extinction coefficient are discussed in detail. The transport properties of alloys are investigated using the semi-classical Boltzmann theory as implemented in the BoltzTraP code in conjunction with ab initio electronic structure calculations. Our findings suggest that Er doping of wide band gap semiconductors could be a viable option for quantum well devices.

SUMMARY: Introduction: The use of button batteries are commonly used today, used in everyday objects such as watches, hearing aids and toys. Its chemicals lead to serious injury. Clinical case: This article describes the case of a 10-year-old boy who threw a battery stack into the fire with explosion and trauma from fragments to the face and paranasal breasts, which evolved into osteomyelitis. The boy underwent several abscess drains that eventually led to the detection of traumatic frontal sinusitis, which was operated on and evolved well. Conclusions: Frontal sinusitis is not common in children and is therefore assumed that there is some foreign body present every time there is a history of trauma.

RESUMEN: Introducción: El uso de baterías de tipo botón es común en la actualidad, utilizada en objetos cotidianos como relojes, audífonos y juguetes. Sus productos químicos conducen a lesiones graves. Caso clínico: Este artículo describe el caso de un niño de 10 años que arrojó una pila de batería al fuego con explosión y traumatismo por fragmentos en la cara y senos paranasales, que evolucionaron hacia osteomielitis. El niño se sometió a varios drenajes de absceso que finalmente condujeron a la detección de una sinusitis frontal de causa traumática, que fue operado y evolucionó bien. Conclusiones: La sinusitis frontal no es frecuente en los niños y, por lo tanto, es suponer que hay algún cuerpo extraño presente cada vez que hay antecedentes de trauma.

ABSTRACT Introduction: Marabú, Dichrostachys cinerea (L.), is expected to be used as biomass for electricity generation in Cuba, as a complementary fuel to sugarcane biomass in sugar industry. For this, large quantities will be required, forcing machines use for harvesting. Fuel properties of marabú biomass, obtained under these conditions, have not been studied in depth. Objective: To determine humidity and temperature of open stacked marabú, and microbial composition, grain size and angle of repose of marabú. harvested with the BMH-480 machine with the H 600 head, pile Materials and Methods: Samples of harvested marabú were obtained, and their properties were determined in several laboratories, as well as field evaluations to determine influential properties in their logistics and combustion. For the assessments, the post-harvest time was mainly taken into account. Results and Discussion: Several of mechanically harvested marabú properties and their dependence with post-harvest time are presented. Conclusions: Moisture of harvested with machines, and open stacked marabú, decreases with time. Initial value is high, but it can decrease to values of 20 % in open drying periods of approximately 12 days. Marabú stack temperature, which is modified with storage time, can reach values of 62 °C. Microbial composition of marabú biomass, its granulometric characteristics and the angle of repose of the stack were also evaluated.

RESUMEN Introducción: El marabú, Dichrostachys cinerea (L.), se ha previsto sea utilizado como biomasa para la generación de electricidad en Cuba, en condición de combustible complementario a la biomasa cañera en la industria azucarera. Para esto se requerirán grandes cantidades, lo que obliga a emplear máquinas para su cosecha. Las propiedades como combustible de la biomasa de marabú, obtenida en esas condiciones, no han sido estudiadas a profundidad. Objetivo: Determinar la humedad y temperatura de la pila de marabú a la intemperie, composición microbiana, granulometría y ángulo de reposo de la pila de marabú cosechado con la máquina BMH-480 con el cabezal H 600. Materiales y Métodos: Se obtuvieron muestras del marabú cosechado y se determinaron sus propiedades en varios laboratorios, además se realizaron evaluaciones de campo para determinar propiedades influyentes en su logística y combustión. Para las evaluaciones se tuvo en cuenta principalmente el tiempo postcosecha. Resultados y Discusión: Se presentan varias de las propiedades del marabú cosechado mecanizadamente y sus dependencias con el tiempo postcosecha. Conclusiones: La humedad del marabú cosechado con máquinas, y apilado a la intemperie, disminuye con el tiempo, la inicial resulta alta, pero puede disminuir a valores del 20 % en períodos de secado a la intemperie de aproximadamente 12 días, y la temperatura de la pila de marabú, que se modifica con el tiempo de almacenamiento, alcanza un valor máximo de 62 °C. Se evaluaron también la composición microbiana de la biomasa de marabú, su granulometría y el ángulo de reposo de la pila.

Abstract The purpose of this paper is to present a shallow-water-type model with multiple inhomogeneous layers featuring variable linear velocity vertical shear and stratification in horizontal space and time. This is achieved by writing the layer velocity and buoyancy fields as linear functions of depth, with coefficients that depend arbitrarily on horizontal position and time. The model is a generalization of Ripa’s (1995) single-layer model to an arbitrary number of layers. Unlike models with homogeneous layers, the present model can represent thermodynamics processes driven by heat and freshwater fluxes through the surface or mixing processes resulting from fluid exchanges across contiguous layers. By contrast with inhomogeneous-layer models with depth-independent velocity and buoyancy, the model derived here can sustain explicitly at a low frequency a current in thermal wind balance (between the vertical vertical shear and the horizontal density gradient) within each layer. In the absence of external forcing and dissipation, energy, volume, mass, and buoyancy variance constrain the dynamics; conservation of total zonal momentum requires also the usual zonal symmetry of the topography and horizontal domain. The inviscid, unforced model admits a formulation suggestive of a generalized Hamiltonian structure, which enables the classical connection between symmetries and conservation laws via Noether’s theorem. A steady solution to a system involving one Ripa-like layer and otherwise homogeneous layers can be proved formally (or Arnold) stable using the above invariants. A model configuration with only one layer has been previously shown to provide: a very good representation of the exact vertical normal modes up to the first internal mode; an exact representation of long-perturbation (free boundary) baroclinic instability; and a very reasonable representation of short-perturbation (classical Eady) baroclinic instability. Here it is shown that substantially more accurate overall results with respect to single-layer calculations can be achieved by considering a stack of only a few layers. Similar behavior is found in ageostrophic (classical Stone) baroclinic instability by describing accurately the dependence of the solutions on the Richardson number with only two layers.