Resumo As proporções de areia nas argamassas de tipo II foram analisadas de acordo com a norma N-CMT-2-01-004/02. Foram utilizados três tipos de agregados da região de Morelia, Michoacán para determinar a sua influência nas suas propriedades físico-mecânicas. Considerando a utilização de diferentes materiais cimentícios (CM): cimento Portland mais cimento de alvenaria (B2) e cimento Portland mais cal (B1). Foram preparadas misturas para B1 e B2 com relações areia/MC de 2,25 para 4. Foram determinadas a fluidez, resistência uniaxial à compressão (UCS) e resistividade elétrica úmida (WER). Estudando a relação entre a fluidez e a quantidade de água/MC, concluindo que o tipo de agregado e as proporções modificam a fluidez e a demanda de água no estado fresco com impacto no UCS e no WER.

Abstract The influence of the sand proportion in mortars Type II was studied, according to the standard N-CMT-2-01-004/02, using three fine aggregates from the region of Morelia, in Michoacan, and determining their influence in the physico-mechanical properties, while considering the use of different cementitious materials (CM): Portland cement plus lime (B1), and Portland cement plus construction cement (B2). Mortar mixtures were designed for B1 and B2 with volume ratios of aggregates/CM, from 2.25 to 4, determining the fluency, the uniaxial compressive strength (UCS) and the wet electrical resistivity (WER). The relation between the fluency and the ratio water/CM were studied, concluding that the aggregate type and the proportions employed modify the fluency and the water demand in the fresh state of the mortar, and consequently impact the UCS and WER.

Resumen Se analizó la influencia de la proporción de arena en morteros Tipo II según norma N-CMT-2-01-004/02 empleando tres tipos de áridos de la región de Morelia, Michoacán determinando su influencia en sus propiedades físico-mecánicas, contemplando el uso de diferentes materiales cementantes (MC): el cemento Portland más cal (B1), cemento Portland más cemento de albañilería (B2). Se elaboraron mezclas para B1 y B2 con relaciones en volumen arena/MC, desde 2.25 hasta 4, determinando la fluidez, resistencia a compresión uniaxial (UCS) y resistividad eléctrica húmeda (WER). Se estudió la relación entre la fluidez y la cantidad de agua/MC, concluyendo que el tipo de árido y proporciones modifican la fluidez y demanda de agua en estado fresco impactando en UCS y WER.

ABSTRACT Encapsulation of poly-unsaturated fatty acid (PUFA)is an alternative to increase its stability during processing and storage. Chia (Salvia hispanica L.) oil is a reliable source of both omega-3 and omega-6 and its encapsulation must be better evaluated as an effort to increase the number of foodstuffs containing PUFAs to consumers. In this work chia oil was extracted and encapsulated in stearic acid microparticles by the hot homogenization technique. UV-Vis spectroscopy coupled with Multivariate Curve Resolution with Alternating Least-Squares methodology demonstrated that no oil degradation or tocopherol loss occurred during heating. After lyophilization, the fatty acids profile of the oil-loaded microparticles was determined by gas chromatography and compared to in natura oil. Both omega-3 and omega-6 were effectively encapsulated, keeping the same omega-3:omega-6 ratio presented in the in natura oil. Calorimetric analysis confirmed that encapsulation improved the thermal stability of the chia oil.

ResumenLa especie más importante de la pesquería del río Vaupés es un pez conocido como Warakú tres puntos (Leporinus friderici), un carácido migratorio representativo del departamento del Vaupés, Colombia, de importancia para la seguridad alimentaria de comunidades indígenas. Con el propósito de contribuir en el conocimiento biológico básico de la especie, el presente estudio determinó los hábitos y preferencias alimenticias de Leporinus friderici durante un ciclo hidrobiológico (marzo 2014 a mayo 2015) en el río Vaupés, Colombia. Fueron muestreados tres lugares, dos a lo largo del río Vaupés (comunidades indígenas de Yacayacá y Santa Cruz) y uno en el río Cuduyarí afluente del río Vaupés (comunidad de Piracemo). Se analizaron 316 contenidos estomacales aplicando los métodos de frecuencia de ocurrencia (FO), índice gravimétrico (W), coeficiente de vacuidad (CV) e índice de importancia relativa (IIR). De igual modo, se determinaron parámetros físicos y químicos del agua superficial y profunda. La profundidad del río en época de aguas ascendentes fue de 3.7 ± 0.6 m, aguas altas de 5.9 ± 1.4 m, aguas descendentes 4.6 ± 1.3 m y en aguas bajas 2.4 ± 1.0 m; se registró mayor acidez y turbidez del agua en las ascendentes. El CV fue de 14.5 %; sin embargo, el CV alcanzó un valor del 40 % en aguas ascendentes. En general se observó una mayor FO de material vegetal en los estómagos de los individuos muestreados (44.4-66.7 %), seguido por los insectos (21.1-33.3 %, dietas secundarias). Los índices gravimétricos reflejaron que el material vegetal fue el ítem consumido en mayor cantidad, seguido de los insectos y en casi igual proporción invertebrados y material animal. Las diferencias en la composición de la dieta confirman la naturaleza oportunista de esta especie con predominio de hábitos omnívoros.Este estudio puede ser utilizado como parte integral del conocimiento de la ecología trófica de la especie, con el fin de crear estrategias para la protección del L. friderici en la región del Vaupés.

AbstractThe most important fish species of the Vaupes river is known as a Warakú tres puntos (Leporinus friderici), the most representative migratory Characidae from the Vaupés state, Colombia, with a significant importance in food security of indigenous communities. To contribute with the knowledge of its basic biology, we determined the habits and food preferences of Leporinus friderici, during one hydrobiological cycle (March 2014 to May 2015) in the Vaupés river, Colombia. Three sites were sampled, two of them along the Vaupés river (Yacayacá and Santa Cruz communities) and the other one in the Cuduyarí river, tributary of the Vaupés river (Piracemo community). Physical and chemical water parameters from the surface and depth level of the river were determined. Stomach contents from 316 fish were analyzed by frequency of occurrence (FO), gravimetric index, vacuity index (VI) and relative importance index (RII). Vaupés’s average depth in ascending water period was of 3.7 ± 0.6 m, during rainy season of 5.9 ± 1.4 m, in descending water period of 4.6 ± 1.3 m and during dry season of 2.4 ± 1.0 m. The higher acidity and turbidity were observed during the ascending water period. The average VI was 14.5 % for the period, but it reached 40 % in descending waters. In general, a FO of plant material was the most frequent (44.4-66.7 %), followed by insects (21.1-33.3 %, secondary diets). The gravimetric indices showed that plant material was the most consumed item, followed by insects, and in almost in equal proportion, invertebrates and animal material. The differences in diet composition confirm the opportunistic nature of this species with a predominance of omnivorous habits. This study can be used as an integral part of the feeding ecology of L. friderici knowledge, in order to develop strategies for its protection in the Vaupés region because of its importance for local communities.

ABSTRACT First records of parasitoids attacking the Asian citrus psyllid in Ecuador. The objective of the current study was to investigate the presence of natural enemies of Diaphorina citri (Hemiptera: Liviidae) (the Asian citrus psyllid) in Ecuador. Incidence of parasitoid Diaphorencyrtus aligarhensis (Hymenoptera: Encyrtidae) was assessed between November 2015 and March 2016, in Letamendi, Febres-Cordero and Tarqui, urban districts of Guayaquil. Highest incidence of parasitism occurred in those regions and seasons of the year with the highest temperatures commensurate with increase of citrus plant shoots. Similar to their host, these parasitoids appear to have established in Ecuador by accident, and were not the result of purposeful introduction. This fortuitous introduction is a potentially helpful tool in controlling the Asian citrus psyllid, and potentially Huanglongbing.

Expanded use of fast photography is proposed to characterize laser ablation plasma plumes by the analysis of a set of photographs by means of appropriate mathematical algorithms. The laser ablation plasma plumes studied were generated by ablation of both a multicomponent target of the nominal composition Ni50Mn37Sn13 and a highly pure Cu target (Cu) using a Q-switched Nd-YAG laser system. The experiments were conducted under different background argon pressures. Several photograph parameters such as intensity per unit time of exposure for a pixel, mean intensity per pixel per unit time of exposure, integrated intensity and cross correlation were studied. The intensity per unit time of exposure allowed for identification of the fast component of the triple structure of the expanding plasma into the background gas (that travels at a speed close to the one measured in vacuum). This parameter together with the use of cross correlation enabled the identification of regions of the expanded plasma plume with higher and lower similarities in their optical emission behavior. The mean intensity per pixel per unit time of exposure can be used as a measurement of the amount of light emitted by the plume as a function of time.

Combustion of organic sulfur from fossil fuels can produce acid rain that deteriorates the environment and infrastructure. Sulfur removal by microorganism has appeared as an alternative for this challenge. In this work, biodesulfurization of 50:50 water-kerosene emulsions were carried out at 100 mL scale and in a 0.01 m³ airlift reactor with resting cells of the reference strain ATCC 39327 and Pseudomonas native strains Nº 02, 05 and 06. The reactor conditions were 30°C, pH 8.0 and 0.34 m³ h-1 air flow. After 7 culture days, the mean sulfur removal for the strains Nº 06 and ATCC 39327 was 64 and 53%, respectively, with a mean calorific power loss of 4.5% for both strains. The use of the native strain Nº 06 and the designed airlift reactor is shown as an alternative for biodesulfurization process and constitute a first step for its scale-up to pilot plant.

OBJECTIVE: To assess the diagnostic accuracy of semen and urine culture in the diagnosis of chronic bacterial prostatitis (CBP). MATERIALS AND METHODS: In 70 consecutive men suspected of having chronic bacterial prostatitis along with 17 asymptomatic controls, we obtained urine and semen cultures followed 1 week later by the Meares and Stamey test, our reference standard. The interpretation of each of the cultures was blind to the results of other tests. RESULTS: 139 men were referred for evaluation of chronic bacterial prostatitis and 70 received all tests. Additionally, 17 control men volunteered to participate. The Meares and Stamey Test was positive in 69 (79%) patients. The semen culture had a sensitivity of 45% and a specificity of 94%. The likelihood ratio associated with a positive semen culture was 8.1 (95% confidence interval (CI) 1.2 to 55.3); the likelihood ratio associated with a negative semen culture was 0.6 (95% CI 0.5 to 0.7). The urine culture had a sensitivity of 4% and a specificity of 100%. The likelihood ratio of a positive urine culture was infinity and of a negative urine culture was 0.96 (95% CI 0.9 to 1). CONCLUSIONS: While a positive semen culture in a symptomatic patient may suffice to select and start antibiotic treatment against chronic bacterial prostatitis, a negative culture does not rule out the condition. Urine cultures alone are not useful for diagnosing CBP. The Meares and Stamey test remains important for the diagnosis of CBP in practice.

Uma das principais limitações relacionadas ao processo de retificação de cerâmica é a confiabilidade do material devido aos defeitos introduzidos no processamento. A compreensão dos mecanismos envolvidos na remoção de material durante a retificação e a interação com os parâmetros de processo e microestrutura é fundamental para minimizar estes defeitos. A proposta desta revisão é apresentar os modelos de remoção de material e a forma como afetam as propriedades mecânicas da peça final.

One of the major restrictions in grinding of ceramics is the probability of failure of material due to the damage induced during the process. The understanding of mechanisms of material removal on grinding and the interaction with the process parameters and microstructure is fundamental to minimize these problems. The purpose of this review is to present the models of material removal in ceramics and the way they affect the mechanical properties of the product.

Fat embolism syndrome (FES) is a clinical entity which consists in the occlusion of blood vessels by fat droplets. It is commonly associated to long bone fractures and it's an important source of morbidity and mortality in polytraumatized patients. Although the first descriptions were made in the nineteenth century, nowadays it continues to be an important clinical challenge determining that, sometimes, the first diagnostic is made at autopsy. In this paper, we present a case of FES in a woman 19 years old who died in hospital twelve days after jumping from a bridge suffering polytraumatism with long bone fracture. FES was suspected clinically and diagnosed in the gross autopsy being confirmed microscopically. The clinic-pathological characteristics of this syndrome are also reviewed.

El síndrome de embolia grasa (SEG) es un cuadro clínico debido a la oclusión de los vasos sanguíneos por glóbulos de grasa. Se asocia fundamentalmente a fracturas de los huesos largos y es una importante fuente de morbilidad y mortalidad en pacientes politraumatizados. Aunque las primeras descripciones se realizaron a finales del siglo XIX en la actualidad sigue siendo un desafío para el clínico por lo que, en ocasiones, el diagnóstico inicial se realiza en la autopsia. Presentamos un caso de SEG en una mujer de 19 años que fallece en el hospital doce días después de precipitarse desde un puente con finalidad suicida sufriendo politraumatismo con fractura de huesos largos. El SEG fue sospechado clínicamente y se diagnosticó en la autopsia macroscópica siendo posteriormente confirmado por los estudios histopatológicos. Así mismo se revisan las características clinico-patológicas del SEG.