Abstract: In the Amazonian forests of Perú a large variety of native wood species can be found, of which only a few are commercially exploited. Exploitation is focused on high density durable hardwoods for flooring applications. After selective logging of a few valuable trees the forests often are considered being “unproductive” because there is no market for most of the remaining trees. Having a long-term sustainable forest management and utilization plan in mind, a continuous extraction of more tree species is desirable. For opening out new markets for lesser-used species a concise knowledge of their physical and mechanical properties is essential. Fifteen lesser-used Peruvian wood species were investigated to characterize their wood/water relations. Density, shrinkage behavior, and sorption characteristics were determined. In addition, the functional relation between electrical resistance and moisture content was determined to provide a sound basis for non-destructive moisture content measurements.

Resumen: El objetivo de este estudio es determinar la frecuencia de eventos adversos de la vacunación contra el COVID-19 en pacientes con LES que son atendidos en centros médicos de referencia en Paraguay. Este es un estudio observacional, transversal, descriptivo. Se incluyeron 52 pacientes con LES que recibieron al menos una dosis de la vacuna anticovid. De los cuales el 100% recibieron la primera dosis, el 92,3% la segunda dosis y el 15,38% la tercera dosis; el 44,6% recibió Sputnik-V; 16% Moderna; 12,5% Pfizer, 7,1% AstraZeneca, 3,6% Covaxin y 2,1% Hayat Vax, 8 pacientes recibieron su tercera dosis correspondiente a 3 de Pfizer, 3 de Moderna, 2 de AstraZeneca. En las 108 dosis aplicadas se registraron un total de 43 evento advserso, el 95,3% dentro de los primeros 5 días y el resto a los 5 días. El 51,2% presentó el evento advserso tras la primera dosis, el 39,5% tras la segunda dosis y el 9,3% tras la tercera dosis. La duración media de los síntomas fue de 2,3 días ±1,4. El efecto adverso más importante fue el dolor en el sitio de inyección, seguido de fiebre y fatiga. La exacerbación del LES también se registró como evento advserso en el 8,3%. Se registraron efectos adversos leves, se concluye que vacunación contra COVID-19 es segura para pacientes con LES.

Abstract: The aim of this study is to determine the frequency of adverse events of COVID-19 vaccination in patients with SLE who are attended at referral medical centers in Paraguay. This is an observational, cross-sectional, descriptive study. Fifty-two patients with SLE who received at least one dose of anticovid vaccine were included. Of which 100% received the first dose, 92.3% the second dose and 15.38% the third dose; 44.6% received SputnikV; 16% Moderna; 12.5% Pfizer, 7.1% AstraZeneca, 3.6% Covaxin and 2.1% Hayat Vax, 8 patients received their third dose corresponding to 3 from Pfizer, 3 from Moderna, 2 from AstraZeneca. In the 108 doses applied, a total of 43 adverse events were recorded, 95.3% within the first 5 days and the rest at 5 days. A total of 51.2% presented the adverse event after the first dose, 39.5% after the second dose and 9.3% after the third dose. The mean duration of symptoms was 2.3 days ±1.4. The most important adverse effect was pain at the injection site, followed by fever and fatigue. Exacerbation of SLE was also recorded as an adverse event in 8.3%. Mild adverse effects were recorded, it is concluded that vaccination against covid 19 is safe for patients with SLE.

RESUMEN El objeto del estudio fue adelantar la revisión y actualización de la lista de especies de copépodos del Caribe colombiano. El método utilizado se basó en la recopilación crítica de registros en artículos publicados y no publicados, y en resultados propios obtenidos en el estudio del zooplancton recolectado durante el desarrollo de un proyecto en bioinvasiones de aguas costeras en 2010. Veinte especies registradas únicamente en tesis de pregrado requieren comprobación taxonómica y fueron excluidas del inventario. El modelo base de la lista de especies fué aquel publicado por Medellín-Mora y Navas (2010). Diez especies recolectadas durante el proyecto mencionado constituyen nuevos registros. Trece especies registradas en publicaciones de otros investigadores después de 2010 enriquecieron el inventario. Un total de 214 especies de copépodos (158 Calanoida, 38 Cyclopoida, 15 Harpacticoida, 2 Mormonilloida y 1 Monstrilloida) conforman actualmente la lista de especies. La mayoría de especies son de hábitos planctónicos (201), pocas son bentónicas (10) o epibentónicas (3). Se actualizó la nomenclatura de los taxones. La mayor diversidad corresponde a la ecorregión Colombia Oceánica (127 especies), seguida por Tayrona (94), Magdalena (82) y Morrosquillo (78). El menor número corresponde al Archipiélago de San Andrés y Providencia (49). La baja información existente sobre copépodos bentónicos y parásitos sugiere incrementar el estudio de esos grupos, la mayoría de ellos pertenecientes a los órdenes Harpacticoida y Siphonostomatoida.

ABSTRACT The aim of the study was to obtain a revised and updated checklist of the species of copepods of the Colombian Caribbean. Methods for updating included a critical compilation of records in published and unpublished articles, and our own results of a study of zooplankton in a project on bioinvasions of coastal waters, conducted in 2010. Twenty taxa reported solely in undergraduate thesis need taxonomical comprobation and were excluded from the inventory. As a baseline, we used the most recent inventory published by Medellín-Mora and Navas (2010). Ten species recorded in the already mentioned project are new records. Thirteen species reported by other researchers in publications after 2010 increased the species list. The inventory totals 214 species of copepods (158 Calanoida, 38 Cyclopoida, 15 Harpacticoida, 2 Mormonilloida and 1 Monstrilloida). Most species are planktonic (201), while only a few are benthic (10) or epibenthic (3). Nomenclature of the taxa was revised and updated as well. The highest copepod diversity corresponds to the ecoregion Colombian Oceanic (127 species), followed by Tayrona (94), Magdalena (82) and Morrosquillo (78). The lowest number corresponds to San Andrés and Providencia Archipelago (49). The limited information existing about benthic and parasitic copepods warrants an increment on the study these groups. Most of them belong to orders Harpacticoida and Siphonostomatoida.

Abstract Although computer-aided engineering (CAE) software has been used for many years in the plastic industry, identifying the most appropriate mesh geometry and density remains a challenge. It can affect the accuracy of the simulation, the time and the costs. The evaluation of the most suitable mesh is not easy because the difficulties to obtain the real the values of the pressure and temperature inside the mold. The current work investigates this issue. A mold was manufactured and sensors were installed in its interior. CAE simulations using different mesh geometries and densities were evaluated against the experimental data. The results showed that the computational time was mostly influenced by the mesh geometry. The use of 2D mesh and lower density can lead to a faster and more precise simulation of pressure inside the mold and 3D mesh with lower density can provide a faster and precise simulation of the temperature.

OBJECTIVE: To describe the clinical course of critically ill children with confirmed pandemic influenza A(H1N1)pdm09 (H1N1) infection in a southern African paediatric intensive care unit (PICU), and to compare them with a similar group with respiratory virus infections other than H1N1 admitted to the same PICU during the same period. METHODS: A retrospective descriptive study of all patients admitted to a PICU in Cape Town, South Africa, who tested positive for H1N1 and other respiratory viruses from 1 August to 30 September 2009. RESULTS: A total of 19 children in 20 PICU admissions tested positive for H1N1 (Group 1). Of these, 14 (70%) had major comorbidities and 4 tested positive for another respiratory virus. Five (26.3%) children in this group died and seven (36.8%) had nosocomial infection. Eight patients in nine PICU admissions who tested H1N1-negative (Group 2), tested positive for other respiratory viruses. Of these, five (55.6%) had major comorbidities. None in this group died. Children in Group 1 had significantly longer ICU. stays, ventilator days and worse indices of organ dysfunction than those in Group 2. CONCLUSIONS: Children admitted to the PICU with confirmed H1N1 tended to have longer ICU stays, prolonged ventilation, more severe organ dysfunction and higher mortality than those with other respiratory viruses. Hospitalisation was identified as a major risk factor for chronically ill children to acquire H1N1 infection requiring intensive care in our setting.

Con el fin de cuantificar el porcentaje de carbón mineral en playas del departamento del Magdalena, (Colombia) se llevó a cabo un procedimiento sencillo para separar el sedimento en fracciones sedimentológicas de acuerdo a su densidad. Se utilizaron sedimentos provenientes de seis playas del departamento colectadas de dos niveles mareales en noviembre de 2012 y febrero de 2013, antes y después de un derrame de una barcaza de carbón, que ocurrió el 12 de enero de 2013. Los sedimentos fueron secados, suspendidos en una solución de sodio politungstato (densidad: 2,0 g*cm-3) y centrifugados. Ya que el carbón tiene una densidad menor (1,2-1,9 g*cm-3) que otros minerales inorgánicos, cualquier partícula de carbón presente en una muestra se concentró en la fracción ligera, mientras que las partículas más densas se sedimentaron. Para eliminar materia orgánica no correspondiente a carbón mineral, se sometió la fracción ligera después a una oxidación leve con peróxido de hidrógeno. Adicionalmente, para estimar un límite máximo del contenido de carbón mineral, se determinó la pérdida de peso de sedimentos enteros a partir de combustión a 550 °C. En las seis playas evaluadas, la pérdida máxima de peso por combustión fue de 2,4 % y el porcentaje máximo de la fracción ligera (densidad < 2 g*cm-3) y resistente a oxidación por H2O2 fue de 0,07 % para noviembre 2012 y el 0,02 % para febrero 2013. No se observaron diferencias significativas en el porcentaje de carbón mineral entre los dos muestreos, sugiriendo que el derrame de carbón que ocurrió en el área en enero 2013 no resultó en un aumento del carbón en las playas, muy probablemente debido a la baja densidad que caracteriza al carbón. Se concluye que el porcentaje de carbón en todas las playas examinadas es menor al 0,1 % y que el aspecto negro en los sedimentos se debe a minerales inorgánicos, poco combustibles a 550 °C, con densidad >3 g*cm-3 y que constituyen entre 10 y 70 % del peso seco total de las muestras.

To quantify the percentage of unburnt coal in beach sediments from the department of Magdalena (Colombia) a simple procedure was devised to separate the sediment mineral phases according to their density. Sediments were collected from six beaches, at two tidal heights, in November 2012 and February 2013, before and after a spill from a coal barge that occurred on 12 January 2013. Sediments were dried, suspended in an aqueous solution of sodium polytungstate (density: 2.0 g*cm-3) and centrifuged. Because coal has a lower density (1.2-1.9 g*cm-3) than other inorganic minerals and rocks, any coal particle present in a sample concentrated in the suspended fraction, whereas more dense particles settled. To remove organic matter not corresponding to coal, the light fraction was subsequently subjected to a weak oxidation with hydrogen peroxide. To estimate an upper limit for any coal present, weight loss on ignition at 550 °C was determined for whole sediments. For the six beaches examined, the maximum weight loss on ignition was 2.4 % and the weight percentage of the light fraction (with a density < 2 g*cm-3) and resistant to oxidation by H2O2 was 0.07 % in November 2012 and 0.02 % in February 2013. No significant differences in coal content were found between the two sampling events, suggesting that the coal spill that occurred in January 2013 did not result in an increase in coal accumulation on the beaches, probably due to coal's characteristic low density. We conclude that the weight percentage of carbon in the six beaches investigated is less than 0.1 % and that sediments owe their black appearance to inorganic minerals, poorly-combustible at 550 °C, with a density > 3 g*cm-3, which comprise between 10-70 % of the total sediment dry weight.

This paper reports the detection of Pseudothyone belli on submerged hard substrates at three sites in Santa Marta during port surveys conducted in March and October 2010. Owing to its high adaptive and competitive capability, it appears likely that the species has established itself in the Colombian Caribbean.

O surgimento das tecnologias de prototipagem rápida (RP) e de ferramental rápido (RT) tem despertado interesse da indústria de moldes de injeção. O vazamento de termofixos com cargas metálicas possibilita a construção de moldes usando materiais compósitos, os quais apresentam maior resistência que os utilizados por outras técnicas RT. Neste trabalho foi estudado o comportamento térmico de moldes fabricados em epóxi/alumínio durante a injeção de polipropileno através de avaliações da estrutura e de propriedades mecânicas utilizando difração de raio X e ensaios de dureza e de tração. Os corpos-de-prova injetados no molde em compósito epóxi/alumínio apresentaram pequenas diferenças no grau de cristalinidade das superfícies analisadas e propriedades mecânicas semelhantes aos corpos-de-prova injetados em molde de aço. O estudo mostrou um razoável desempenho térmico do molde compósito durante a injeção de polipropileno evidenciando a viabilidade de utilização destes moldes na produção de pequenas séries de protótipos e de produtos neste termoplástico.

rapid prototyping (RP) and rapid tooling (RT) technologies are gaining increasing importance in the injection molding industry. Casting of resin/metal composites allows the construction of molds with greater resistance than those manufactured by other RT techniques such as Stereolithography. In this work, the thermal behavior of molds manufactured in epoxy/aluminum during the injection molding of polypropylene specimens was investigated. Structural and mechanical characterization of the molded specimens included X ray analysis, hardness and tensile testing. The samples presented small differences in the degree of crystallinity and similar mechanical properties in comparison with samples injected into steel molds. This study showed a reasonable thermal performance of the epoxy/aluminum mold during the injection molding of polypropylene, thus demonstrating the viability of using these molds to produce a few number of prototypes or products with this thermoplastic.

Currently, miniaturization is a major trend in the manufacturing and commercialization of new industrial products. When small-sized objects should be manufactured with dimensions of only a few millimeters or less, many difficulties can appear using traditional processes. An alternative to study these new requirements is through the use of rapid prototyping technologies. Stereolithography (SL) has established itself as one of the most popular and reliable process allowing the rapid manufacturing of complex parts. This paper investigates the SL process, which directly produces small parts by rapid manufacturing, and also indirectly by rapid tooling. The processability of small parts was investigated using two different shapes. The POM and ABS materials were used in the indirect manufacturing. The dimensional accuracy, precision and tolerance of micro parts were evaluated using metrological techniques. Results showed accuracy and precision greater than 97% when small-parts are manufactured directly by Stereolithography.

In this study HDPE specimens were fabricated by selective laser sintering using different particle sizes to obtain controlled variations in the porosity. Electron microscopy, density measurements and mechanical analyses were conducted for the characterization of the specimens. Parts with controlled pore gradients were also manufactured and characterized. The specimens with larger particle sizes had a high sintering degree and a significant level of close pores, as shown by microscopy and density analyses. However, the mechanical properties of specimens prepared with large particles had low values due to the limited density of union points, i.e., low neck number/area. HDPE parts with pore gradients were prepared by selective laser sintering demonstrating that this technique can be used to easily control the structure and the properties of the parts manufactured. This technology may have applications in areas such as drug delivery devices and scaffolds for tissue engineering.

A fabricação de moldes por técnicas de prototipagem rápida, como a estereolitografia (SL), é considerada uma importante tecnologia no auxílio ao desenvolvimento de produtos de plástico moldados por injeção. Embora esta tecnologia se mostre vantajosa, a vida útil dos moldes pode ser bastante reduzida em decorrência, por exemplo, de forte adesão entre o polímero injetado e o material do molde SL. Neste trabalho é investigado o uso da técnica de recobrimento metálico com Ni-P por deposição electroless sobre moldes de injeção, fabricados por SL com a resina DSM SOMOS 7110®. Foram comparados resultados de moldagem de PA6.6 em moldes fabricados com e sem recobrimento metálico evidenciando a possibilidade de utilizar a técnica de metalização como alternativa para a moldagem deste material em moldes SL, uma vez que a vida útil foi superior.

Manufacturing of moulds by rapid prototyping processes, such as stereolithography (SL), is considered an important technology to aid the development of injection moulding plastic products. Although this technology shows significant advantages, the lifetime of moulds may be drastically be reduced due to strong adhesion between the injected polymer and the material of the SL mould. This work investigates the use of Ni-P metal coating obtained by electroless deposition on SL moulds manufactured with the resin DSM SOMOS 7110. Specimens of PA6.6 have been injected into SL moulds manufactured with and without metal coating. The results showed that the electroless metal coating process can be an appropriate alternative to allow moulding of small series of PA6.6 parts in SL moulds.

O objetivo deste trabalho foi verificar a qualidade física e fisiológica das sementes de trigo em função da utilização de gás liquefeito de petróleo (GLP) na secagem estacionária e determinar a curva de secagem em comparação à secagem estacionária em estufa. Sementes de trigo, cultivar OR-I, com teor de água inicial de 15,3%, foram secas até 12,6%, em um secador estacionário de tubo central horizontal perfurado. A amostragem das sementes foi realizada em intervalos de 45 minutos durante a secagem, em três posições diferentes do cilindro central (proximal, mediana e distal da fonte de calor). A qualidade física da semente foi avaliada pelo teor de água, peso de mil sementes e temperatura da massa de semente em pontos distintos. A qualidade fisiológica foi avaliada por testes de vigor e germinação. A velocidade média obtida na secagem a gás foi de 0,9 pontos percentuais por hora (pph-1). O tempo dispendido para a redução do teor de água de 15,3% para 12,6%, foi de três horas, além de mais uma hora usada para o resfriamento da semente. A velocidade de secagem reduz a medida que aumenta a distância das sementes ao cilindro central (no ponto proximal à fonte de calor 1,00pph-1 e no ponto distal 0,73pph-1), em função da temperatura da massa de sementes ser maior no ponto proximal. A temperatura na massa de semente aumenta gradativamente nos pontos mais próximos à fonte de calor durante a secagem. A temperatura de secagem permanece estável durante o processo com a utilização de gás liquefeito de petróleo. Os resultados dos testes de germinação e vigor mostram a possibilidade de utilização do gás liquefeito de petróleo como combustível na secagem estacionária de sementes de trigo.

The purpose of this study was to verify wheat seed physiological and physical quality while using petroleum liquified gas (LPG) for stationary drying and to determine the drying curve in comparison to the stationary drying in an oven. Wheat seeds, variety OR-I, with 15,3% initial water contents were dried down to 12,6%, in a stationary dryer with a perforated horizontal central tube. Samples were taken at 45 min. intervals of the seeds set in three different positions from the central cylinder (proximal, median and distal from the heat source), during the drying process. The physical seed quality was evaluated by water contents, weight of one thousand seeds, temperature of the seeds mass at different points. The physiological seed quality was evaluated by germination and vigor. The average speed obtained in the drying by gas was 0,9 percent points per hour (pph-1). The seeds were dried down from 15,3% to 12,6%, taking three hours, plus one more hour for cooling. The drying speed was reduced as the distance of the seeds from the central cylinder increased (at the proximal point to the heat source 1,00pph-1 and at the distal point 0,73pph-1) because the temperature of the seed mass was higher at the proximal point. The temperature of the seed mass increased gradually in the points closer to the heat source during the drying process. The seed physiological quality was assessed by tests of germination and vigor, which demonstrated the possibility of using petroleum liquefied gas in the drying process with the temperatures applied.

Paper dryer surface contamination can influence the severity of fiber picking, result in increased adhesion of the paper web to the surface, and impact the severity of cockle (out-of-plane deformation), a paper quality issue. The Web Adhesion and Drying Simulator (WADS) is a unique apparatus designed for investigation of paper sticking and fiber picking. Using the WADS, it has been found that the work of separation and amount of picking depend on roll surface material, contamination and temperature, and on the composition, moisture content and temperature of the web, and contact time. The WADS was also found to be convenient for studying the effect of drying conditions on severity of cockle. Cockle was found to depend on ingoing sheet solids content, surface temperature and degree of heat transfer non-uniformity.

Os processos de prototipagem rápida (Rapid Prototyping - RP) e ferramental rápido (Rapid Tooling - RT) surgiram para reduzir os tempos de desenvolvimento de produtos na fase de projeto diminuindo a necessidade de retrabalhos e, conseqüentemente, antecipando a entrada de novos produtos no mercado. Neste trabalho foi utilizada uma das tecnologias de prototipagem rápida, denominada Modelagem por Fusão e Deposição (FDM), na construção de moldes em ABS com o objetivo de investigar sua aplicação na moldagem por injeção de termoplásticos. Amostras das peças injetadas foram submetidas a ensaios de difração de raios X, dureza Shore D e tração. Os resultados mostraram a viabilidade de fabricar pequenos lotes de peças em PEBD e PP com propriedades mecânicas bastante similares às encontradas em peças moldadas em moldes metálicos.

Rapid Prototyping and Rapid Tooling are aimed at reducing the development time of products in the design phase by minimizing re-workings and, consequently, reducing the time to launch new products. In this work one of the technologies of rapid prototyping, called Fused Deposition Modeling (FDM), was used in the construction of ABS molds with the objective of investigating its application in the injection molding of thermoplastics. Specimens of the molded parts were characterized with X-ray diffraction, Shore D hardness and tensile tests. The results demonstrated the viability to manufacture small batches of LDPE and PP parts with mechanical properties similar to those molded parts in metallic molds.