Análisis de la distribución del tamaño de partícula de agregados de porfirinas por dispersión dinámica de luz

Porphyrins are essential compounds involved in a variety of processes,the formation of its aggregates received considerable interest dueto the different optical and electronic applications. The distribution of theparticle size is a critical property for characterizing systems of particlesin suspension of molecular aggregates. In this paper we studied the distributionof the particle size of aggregates of tetracarboxyphenylprophyrinsof Zn (TCPPZn) and Cu (TCPPCu). Compounds were synthesized usingthe methodology developed by Achar. Compounds were characterized byUV-Vis spectrophotometry and the particle size in solution was determinedthrough Photon Correlation Spectroscopy. Spectrophotometry resultsshowed typical signals to tetracarboxyphenylprophyrins, furthermore, thestudy of aggregate size showed a mean value of 5419 nm for aggregatesof TCPPZn while for TCPPCu was 5560 nm.La formación de sus agregados recibe considerable interésdebido a las distintas aplicaciones ópticas y electrónicas. La distribucióndel tamaño de partícula es una propiedad fundamental para caracterizarsistemas de partículas en suspensión de agregados moleculares. En estetrabajo se estudió la distribución del tamaño de partícula de agregados detetracarboxifenilporfirinas de Zn (TCPPZn) y Cu (TCPPCu) en solución.Los compuestos fueron sintetizadas utilizando la metodología desarrolladapor Achar. Las tetracarboxifenilporfirinas fueron caracterizadas porespectrofotometría y el tamaño de partícula en solución fue determinadopor Espectroscopia de Correlación Fotónica (ECF). Los resultados deespectro fotometría mostraron las señales características de tetracarboxifenilporfirinas;adicionalmente el estudio del tamaño de agregados mostróun valor promedio de 5419 nm para los agregados de TCPPZn, mientrasque para la TCPPCu fue de 5560 nm

The management of social networks in the news on national TV in Ecuador

La investigación está enfocada en la gestión de las redes sociales en los programas informativos de la televisión de Ecuador. La metodología empleada es cualitativa y cuantitativa a tra- vés de fichas de análisis y encuestas, en lo referente al uso de redes sociales en espacios informativos se encuestó a presentadores y directores de noticias delas estaciones Ecuavisa, Teleamazonas y Ecuador TV; respecto al bajo impacto de las cadenas de televisión nacionales en redes sociales se encuestó a presentadores y directores de noticias deRTU y Telerama. Se complementó la investiga- ción con entrevistas semi-estructuradas a directores de noticias.Las redes sociales forman parte de la actividad periodística de comunicadores y directores de noticias. Las redes sociales y la TV se complementan. Las conversaciones suscitadas a través de plataformas digitales influyen y en algunos casos determinan la agenda temática. En Ecuador aún existen canales que no tienen una cuenta dedicada exclusivamente a las emisiones informativas, por lo que usan la cuenta general del canal para transmitir informaciónThe research is focused on the management of social networks in television news pro- grams of Ecuador. The methodology is qualitative and quantitative profiles through analysis and sur- veys regarding the use of social networks news programs presenters and news directors of the Ecuavisa, Teleamazonas and Ecuador TV stations were surveyed; from the low impact of national television presenters social networks and news directors surveyed RTU and Telerama. Research was supplemented with semi-structured interviews news directors. Social networks are part of jour- nalism communicators and news directors. Social networks and TV complement. The talks raised through digital platforms influence and in some cases determine the thematic agenda. In Ecuador there are still channels that do not have an account dedicated to news broadcasts, so they use the general account of the channel to transmit informatio

The Strategy of Combining Antidepressants in the Treatment of Major Depression: Clinical Experience in Spanish Outpatients

Introduction. The combination of antidepressants is a useful tool in the treatment of major depression, especially in cases where there is a partial response to antidepressant monotherapy. However, the use of this strategy is a matter of controversy, and its frequency of use in clinical practice is not clear. The aim of our study is to assess the use of antidepressants combination in Spain by reviewing three databases used between 1997 and 2001. Methods. Databases pertain to patients who are study subjects of major depression treatment. These databases are a result of studies performed in Spain and in which 550 psychiatrists participated. The total studied sample was comprised of N = 2, 842 patients, aged over 18, fitting DSM-IV criteria for Major Depressive Episode. The percentage of patients who received more than one antidepressant and the types of combinations used was described. Subsequently, a comparative study between the group which received a combination of antidepressants (N = 64) and the group which received antidepressant monotherapy (N = 775) was performed. Results. 27.1% of patients were on antidepressive monotherapy treatment, and 2.2% were on combination therapy. In the comparison of patients on combination therapy and monotherapy, there were significant differences only in episode duration (P = 0.001). The most frequent combinations are SSRIs and tricyclic antidepressants. The active principle most widely combined is fluoxetine. Conclusions. The prevalence of use of antidepressant combination therapy is 2.2% of the global sample and 8.3% of treated patients. Other than duration of the depressive episode, no clinical characteristics exclusive to patients who received combination rather than monotherapy were found. Our study found that the most frequent combination is SSRIs + TCAs, also being the most studied

Estudio de la actividad antioxidante de la naringina extraida de la cascara de Citrus aurantium contra radicales libres /

In this work we determined free radical scavenging of the Citrus aurantium peel (orange peel) extract. Naringin was isolated from the fruit peel from Citrus aurantium for using liquid-liquid solvent extraction method; it was characterized by spectroscopic techniques (UV-vis and FT-IR analysis). The scavenging free radical of naringin was evaluated by monitoring radical cation bleaching of ABTS•+ by visible spectroscopy at 734 nm. Assays were compared to reference antioxidants BHT, α-tocopherol and Trolox. Results indicated a minimal extract concentration of 5.0x103 was required to present antioxidant activity; furthermore, results also showed the extract from the peel of citrus aurantium has antioxidant activity against free radicals, under our experimental conditions, naringin extract had scavenging free radicals of 43.06 % and best reference antioxidant had scavenging free radicals of 50.36 %.En este trabajo determinamos la actividad antioxidante del extracto obtenido de la cáscara de Citrus aurantium (cáscara de naranja). El extracto de naringina fue separada de la cáscara de la fruta de la Citrus aurantium utilizando la extracción líquido-líquido como método de separación; el compuesto obtenido fue caracterizado por medio de espectrofotometría UV-Vis y espectroscopía infrarroja con transformada de Fourier (FT-IR). La actividad antioxidante de la naringina fue determinada monitoreando el cambio en la concentración del catión radical ABTS•+ por espectrofotometría a una longitud de onda de 734 nm; como patrones de referencia se utilizó el BHT, α-tocoferol y el Trolox. Los resultados mostraron que el extracto de la cáscara de la Citrus aurantium presenta actividad antioxidante contra radicales; bajo nuestras condiciones experimentales, el extracto presentó un actividad antioxidante del 43.1 %, en comparación el mejor resultado para los antioxidantes de referencia fue del 50.4 %

Cyanobacterial biomass pigments as natural sensitizer for tio2 thin films

In this work, we studied the effect of TiO2 sensitization with dry biomass extracted of cyanobacteria on the degradation of methylene blue dye (AM). Cyanobacterial cultures isolated from water samples were collected from the swamp of Malambo in Colombia; two main genera of cyanobacteria were identified, and they were cultivated with BG-11 culture medium. The concentrations of chlorophyll a in the exponential and stationary phases of growth were measured; the phycobilin content was quantified by spectrophotometry. Thin films of TiO2 were deposited by a doctor blade method, and they were sensitized by wet impregnation. Furthermore, a methylene blue (MB) photodegradation process was studied under visible light irradiation on the cyanobacterial biomass sensitized TiO2 material (TiO2/sensitizer); besides, the pseudo-first-order model was used to obtain kinetic information about photocatalytic degradation. The results showed that the BG-11+ treatment reported a higher amount of dry biomass and phycobiliproteins. After the sensitization process, the TiO2/sensitizer thin films showed a significant red shift in the optical activity; besides the thin film roughness decreasing, the TiO2/sensitizer showed photocatalytic activity of 23.2% under visible irradiation, and besides, the kinetic () constant for TiO2/sensitizer thin films was 3.1 times greater than the value of TiO2 thin films. Finally, results indicated that cyanobacterial biomass is a suitable source of natural sensitizers to be used in semiconductor sensitization.Universidad del Atlántico, Universidad de la Costa, Institución Universitaria Politécnico Gran Colombiano, Universidad Central, Universidad Minuto de Dios, Pontificia Universidad Católica de Chile, Millennium Nuclei on Catalytic Processes towards Sustainable Chemistry

Análisis del contenido de metales pesados en pastos ganaderos por medio de Espectroscopia Dispersiva de Fluorescencia de Rayos-X

En este trabajo se muestra un método analítico práctico y sencillo para cuantificar el contenido de metales pesados en pastos utilizados para alimentar ganado localizado en áreas próximas a zonas con flujo vehicular. La técnica utilizada en este trabajo mostró ser útil, de fácil implementación, amplio rango dinámico y gran rendimiento. Los análisis fueron realizados en un Espectrofotómetro de Fluorescencia de Energía Dispersa de Rayos-X (EDX). El método de parámetros fundamentales fue utilizado como método analítico. El análisis de los pastos mostró un elevando contenido de Fe y Mn. Además, los resultados indicaron que el contenido de metales pesados fue mayor para los pastos que se crecieron cerca de la carretera; el Fe fue el elemento que presentó la mayor concentración mientras que el Cu presentó el menor contenido, finalmente se determinó la distancia mínima de la carretera requerida para asegurar un contenido mínimo de metales pesados.Abstract: In this work, we show an easy and practical analytical method to quantify the content of heavy metals in grass used to feed cattle located in areas of high vehicle traffic flow. Technique used in this work proved to be useful, easy sample preparation, wide dynamic range, and high performance. Analyzes were performed on a Fluorescence Spectrometer Energy Dispersive X- Ray (EDX). Quantification of metals was performed using the method of fundamental parameters. The analysis of the grass showed high content of elements such as Fe and Mn. Along, results indicated heavy metals concentration was highest in the proximity to the vehicle road, element Fe had highest concentration and element Cu had the lowest concentration, finally we determined minimal distance to the road vehicles to ensure the heavy metals concentration was minimal

Characterizing the limited use of point-of-care ultrasound in Colombian emergency medicine residencies

Background: Emergency medicine (EM) is a growing specialty in Colombia with five residency programs in the country. EM leadership is interested in incorporating point-of-care (POC) ultrasound into a standardized national EM residency curriculum. This study is a nationwide survey of Colombian EM residents designed to explore the current state of POC ultrasound use within EM residencies and examine specific barriers preventing its expansion. Methods: We conducted a mix-methodology study of all available current EM residents in the five EM residencies in Colombia. The quantitative survey assessed previous ultrasound experience, current use of various applications, desire for further training, and perceived barriers to expanded use. Focus group discussions (FGDs) were conducted with current EM residents to gather additional qualitative insight into their practice patterns and perceived barriers to clinician-performed ultrasound. Results: Sixty-nine EM residents completed the quantitative survey, a response rate of 85% of all current EM residents in Colombia; 52% of resident respondents had previously used ultrasound during their training. Of these, 58% indicated that they had performed 40 scans. The most frequently used applications indicated by respondents were trauma, obstetrics, and procedures including vascular access. A quarter indicated they had previously received some ultrasound training, but almost all expressed an interest in learning more. Significant barriers included lack of trained teachers (indicated by 78% of respondents), absence of machines (57%), and limited time (41%). In FGDs, the barriers identified were inter-specialty conflicts over the control of ultrasonography, both institutionally and nationally, and program-specific curriculum decisions to include POC ultrasound. Conclusion: While currently limited in their access, EM residents in Colombia have a strong interest in integrating POC ultrasound into their training. Current barriers to expanded use include traditional barriers such as a lack of equipment seen in many developing countries, as well as inter-specialty conflicts typical of developed countries. Further collaboration is underway to help overcome these obstacles and integrate POC ultrasound into Colombian EM residency training

Variaciones interanuales en las capturas de tiburones pelágicos en el

Pelagic migrating sharks are by-caught incidentally in longline fisheries. Some of these species have been catalogued as threatened or vulnerable by several Regional Fisheries Organizations and International Conservational NGOs. Alboran Sea is an important area for pelagic migrating sharks because it is the natural and unique communication way between the Atlantic Ocean and Mediterranean Sea. This area is considered by several authors as a hot-spot of Climate Oscillation, such as the North Atlantic Oscillation (NAO) and the Arctic Oscillation (AO). In addition, Alboran Sea is an important fishing ground where the longline fisheries targeting swordfish operates. Recent studies concluded that historical landing of pelagic sharks from harbours of Alboran Sea and Balearic Sea were mediated for atmospheric oscillations. The main aim of the present study was to assess the effect of atmospheric oscillation on the Catch per Unit Effort (CPUE) of vulnerable sharks thresher shark, Alopias vulpinus (Bonnaterre, 1788) and shortfin mako, Isurus oxyrinchus (Rafinesque, 1810) by-caught in the traditional longline fisheries. The atmospheric oscillations tested in this study were the North Atlantic Oscillation (NAO) and the Arctic Oscillation (AO). We found a significant positive correlation between the NAO and AO indexes of the previous year to the CPUE tested.En prens

Análisis preliminar del efecto de las oscilaciones climáticas sobre la condición física de la melva (Auxis rochei) post-reproductora en el Mar de Alborán

The Mediterranean Sea is considered by several authors as a hot-spot of Climate Oscillation, such as the North Atlantic Oscillation (NAO) and the Arctic Oscillation (AO). However, information about the effect of the climate oscillations on the fitness of the species is still scarce. In this context, bullet tuna is an important migratory species with a substantial socio-economical value, whose fisheries might be affected by the effect of certain climatological conditions. In fact, these atmospheric oscillations trigger a chain of hydrodynamic events, leading a change on the timing, destinations, and success of the migratory species in their search for spawning grounds. This study relies on the hypothesis of a correlation between the physical condition of the post-spawning bullet tuna and climate oscillation indexes. For that purpose, 151 individuals of bullet tuna, Auxis rochei, were collected in the traps of Ceuta (Alboran Sea) during three different years, (1983, 1984 and 2014). The physical condition index was calculated, and later statistically correlated with the climate oscillation indexes proposed. Significant differences were found between the physical condition of A. rochei and the average accumulated NAO index. Moreover, for age class 3+ we obtained a significant correlation with atmospheric oscillations.Postprin

Characteristics of emergency medicine residency programs in Colombia

Introduction: Emergency medicine (EM) is in different stages of development around the world. Colombia has made significant strides in EM development in the last two decades and recognized it as a medical specialty in 2005. The country now has seven EM residency programs: three in the capital city of Bogotá, two in Medellin, one in Manizales, and one in Cali. The seven residency programs are in different stages of maturity, with the oldest founded 20 years ago and two founded in the last two years. The objective of this study was to characterize these seven residency programs. Methods: We conducted semi-structured interviews with faculty and residents from all the existing programs in 2013-2016. Topics included program characteristics and curricula. Results: Colombian EM residencies are three-year programs, with the exception of one four-year program. Programs accept 3-10 applicants yearly Only one program has free tuition and the rest charge tuition. The number of EM faculty ranges from 2-15. EM rotation requirements range from 11-33% of total clinical time. One program does not have a pediatric rotation. The other programs require 1-2 months of pediatrics or pediatric EM. Critical care requirements range from 4-7 months. Other common rotations include anesthesia, general surgery, internal medicine, obstetrics, gynecology, orthopedics, ophthalmology, radiology, toxicology, psychiatry, neurology, cardiology, pulmonology, and trauma. All programs offer 4-6 hours of protected didactic time each week. Some programs require Advanced Cardiac Life Support, Pediatric Advanced Life Support and Advanced Trauma Life Support, with some programs providing these trainings in-house or subsidizing the cost. Most programs require one research project for graduation. Resident evaluations consist of written tests and oral exams several times per year. Point-of-care ultrasound training is provided in four of the seven programs. Conclusion: As emergency medicine continues to develop in Colombia, more residency programs are expected to emerge. Faculty development and sustainability of academic pursuits will be critically important. In the long term, the specialty will need to move toward certifying board exams and professional development through a national EM organization to promote standardization across programs. © 2017 Patiño et al