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Low-cost instrument to carry out automated colorimetric analysis.

A lab-made device was built to analyse phosphate in four different matrices using a smartphone as a capturing device.

The characterization of red pigments in frescoes wall paintings has been of great interest for researchers to better understand raw material procurement dynamics, pigment receipts, stylistic evolution and to assess their conservation state. In this study a non-destructive colorimetric approach implementing a smartphone-based method was developed in order to be able to distinguish between three pigments made from minium, haematite and cinnabar minerals, and also mixed pigments, preparing frescoes mock-ups following the roman receipt described by Vitruvius. Portable FT-IR, Raman spectroscopy, portable XRF and visible reflectance spectra analyses were carried out as reference methods for smartphone colorimetry results validation. Employing a reference colour sheet to control changing lighting conditions, different chemometric approaches have been developed and tested, cross-referencing standard analytical results with the data obtained by smartphone. Overall, using only colour parameters from the smartphone, a Linear Discriminant Analysis and a Support Vector Classifier were tested to efficiently classify each sample based on the red pigment used, with low prediction errors. This work shows the potential of smartphones as cheap, fast and user-friendly analytical devices for the screening of frescoes, and as a prior selective step before carrying out further more expensive and specialized analyses.

The present study describes the behavior of mood states in high performance athletes belonging to a University team in the national championship. For this purpose, twenty-five athletes were surveyed using the “Profile of Mood States” (POMS) instrument, in their adapted version, before (pretest) and immediately after (post-test) competing in the national final of the University Sports Leagues of Chile. The test consisted of 51 adjectives, grouped into five big factors: tension, depression, anger, vigor and fatigue. In the pretest, the factors that presented a higher score on the scale of 0-4 were: vigor (2.59), tension (1.57), followed by fatigue (.99), anger (.43) and depression (.34). In the posttest: vigor (1.66) and fatigue (1.39), followed by anger (.66), tension (.64) and depression (.33). Significant differences were found (on the basis of the value p≤.05) in the pretest vs. post-test for tension and vigor, with higher values in both cases than in the pretest. In conclusion, the tension and vigor factors are higher before to the competition, decreasing after the competition. These results could help coaches and professionals in the athletes’ preparation for important competitions.

In this work, a colorimetric analysis of adulterated tuna samples is carried out using both a spectroradiometer and a smartphone as capture devices. Yellowfin tuna (Thunnus albacares) slices were treated with nitrate and nitrite salts, as well as with two different vegetable extracts (beetroot and radish), and the resulting NO

Introduction and objectives The COVID-19 outbreak has had an unclear impact on the treatment and outcomes of patients with ST-segment elevation myocardial infarction (STEMI). The aim of this study was to assess changes in STEMI management during the COVID-19 outbreak. Methods Using a multicenter, nationwide, retrospective, observational registry of consecutive patients who were managed in 75 specific STEMI care centers in Spain, we compared patient and procedural characteristics and in-hospital outcomes in 2 different cohorts with 30-day follow-up according to whether the patients had been treated before or after COVID-19. Results Suspected STEMI patients treated in STEMI networks decreased by 27.6% and patients with confirmed STEMI fell from 1305 to 1009 (22.7%). There were no differences in reperfusion strategy (> 94% treated with primary percutaneous coronary intervention in both cohorts). Patients treated with primary percutaneous coronary intervention during the COVID-19 outbreak had a longer ischemic time (233 [150-375] vs 200 [140-332] minutes, P

A microporous material made of cyclodextrin units covalently immobilized into a silica network has found an innovative bioanalytical application in the sample clean-up and simultaneous isolation of three synthetic cannabinoids (ADB-CHMICA, MMB-CHMICA, and MDMB-CHMCZCA) from human oral fluid through solid-phase extraction. The subsequent quantitation is carried out using liquid chromatography coupled to fluorescence detection. The optimized experimental procedure gives recoveries ranging from 76% to 96% in oral fluid samples spiked with the studied cannabinoids at the µg L-1 level. High selectivity is obtained through the extraction procedure due to the presence of cyclodextrin in the silica network of the solid phase and thanks to the use of fluorescence detection in the separation technique. It is precisely the type of detection chosen that also gives the developed method a great sensitivity. The limits of detection of the proposed analytical method range from 0.11 to 0.73 µg kg−1 and high repeatability is observed, with variations lower than 6%. The obtained results demonstrate the versatility and high potential of cyclodextrin-silica porous materials for the sorption of the studied substances, contributing in a novel way to the proper determination of third-generation synthetic cannabinoids in biological samples.

Fil: Cruz, Rosa. Universidad Nacional del Nordeste. Facultad de Ciencias Económicas; Argentina. Fil: De Castro, Idalia Gabriela. Universidad Nacional del Nordeste. Facultad de Ciencias Económicas; Argentina. Fil: Sáez, Roberto. Universidad Nacional del Nordeste. Facultad de Ciencias Económicas; Argentina. En el Chaco se conjugan, la importancia económica del cultivo de soja con la significación social de las pequeñas empresas agrícolas, predominantemente familiares. Éstas, necesitan una planificación económico–financiera ya que el alto valor de los activos permanentes extiende el período de recupero de la inversión; la mayor exposición al riesgo e incertidumbre y la naturaleza de su proceso productivo generan costos diferentes en cada campaña; y la falta de correlación temporal entre cobros y pagos compromete permanentemente su flujo de fondos. El objetivo de este trabajo es identificar y analizar la composición de la estructura de costos de producción de una pequeña explotación sojera ubicada en la Provincia del Chaco. Siendo este un paso necesario para –en un trabajo posterior– avanzar en la valoración de la eficiencia y la evaluación de la rentabilidad de estas empresas agrícolas. Se adoptó un enfoque clásico de investigación cuantitativa, su diseño metodológico responde a las características de un estudio técnico, descriptivo, retrospectivo, transversal y predominantemente teórico. Los instrumentos de observación se correspondieron con la naturaleza de los elementos del costo y el protocolo agronómico indicado permitiendo, a partir de datos provenientes de fuentes secundarias: un análisis detallado de los componentes físicos y monetarios, un modelo empírico para determinar el costo de producción y la construcción del indicador: costo de producción por hectárea los cuales podrán actualizarse periódicamente. Los resultados obtenidos se consideran una importante contribución a la asistencia técnica de este grupo de empresas. The economic importance of soybean production in the province of Chaco is frequently linked to the social importance of small agricultural enterprises, mainly family-owned ones. They need an economic-financial planning since the continuous high assets prices extend the period of recovery of the investment; the higher exposure to risk and the uncertainty of the nature of the production process generate different expenses for each cropyear. Besides, the lack of temporal correlation between payments and collections constantly compromises their cashflow. The aim of this study is to identify and analyze the structure of production-cost of a smallscale soybean production in the province of Chaco. It is necessary to carry out this work so that, in a subsequent research study, we will be able to deal with the efficiency assessment and the evaluation of cost-effectiveness of these agricultural companies. In this quantitativestudy a classical approach was used and the methodology applied was technical, descriptive, retrospective and transversal and, mainly, theoretical. The observation instruments used were consistent with the nature of the cost elements and the indicated agronomic protocol, which allowed, considering the data coming from secondary sources, a detailed analysis of the physical and financial components, an empirical model to determine the production costs, and the construction of the following indicator: production cost by hectare, which could be periodically updated. The results that have been obtained constitute a significant contribution for the technical assistance for this group of enterprises.

The aim of this study is to propose national diagnostic reference levels (DRL) for updating in the field of interventional cardiology and to include technical details to help plan optimization. Medical physics experts and interventional cardiologists from 14 hospitals provided patient dose indicators from coronary angiography and percutaneous coronary interventions. Information about X-ray system dose settings and image quality was also provided. The dose values from 30,024 procedures and 26 interventional laboratories were recorded. The national DRLs proposed for coronary angiography and percutaneous coronary interventions were respectively 39 and 78 Gy·cm2 for air kerma area product (PKA), 530 and 1300 mGy for air kerma at reference point (Ka,r), 6.7 and 15 min of fluoroscopy time and 760 and 1300 cine images. 36% of the KAP meters required correction factors from 10 to 35%. The dose management systems should allow these corrections to be included automatically. The dose per image in cine in reference conditions differed in a factor of 5.5. Including X-ray system dose settings in the methodology provides an insight into the differences between hospitals. The DRLs proposed for Spain in this work were similar to those proposed in the last European survey. The poor correlation between X-ray systems dose settings and patient dose indicators highlights that other factors such as operation protocols and complexity may have more impact in patient dose indicators, which allows a wide margin for optimization. Dose reduction technology together with appropriate training programs will be determinant in the future reduction of patient dose indicators.

OBJECTIVES There is a wealth of published data on blood pressure (BP) and physical activity in adults of European descent, but less information is available for Amerindian schoolchildren. The aim of this study was to investigate whether BP and other cardiometabolic risk factors differ by physical activity levels in schoolchildren from different ethnic backgrounds. METHODS This was a cross-sectional study of 540 schoolchildren (6-13 years) from two ethnic backgrounds (n = 119 Mapuche Amerindians and n = 421 of European descent). Physical activity was measured using international physical activity recommendations and a standard questionnaire, and ethnicity was classified according to previous methods using surnames. The population was divided into the following four groups: (a) physically active Mapuches (n = 45) and of European descent (n = 101); and (b) physically inactive Mapuches (n = 74) and of European descent (n = 320). RESULTS In physically inactive schoolchildren, significant differences were found between schoolchildren of Mapuche and European descent in systolic (134 ± 3 mmHg vs 130 ± 5 mmHg, respectively, P = .034) and diastolic BP (85 ± 13 mmHg vs 81 ± 3 mmHg, P = .029). For other cardiometabolic risk factors, schoolchildren with Mapuche surnames were significantly less likely to be classified with normal weight (5 [6.8%] vs 85 [26.6%]), and more likely to be obese (30 [40.5%] vs 76 [26.6%]) at P

The main objective of this study was to evaluate the effect of incorporating polyphenolic-enriched fractions from murta leaves on the oxidative stability of linseed oil microencapsulated by spray drying. For this purpose, polyphenol-enriched fractions from murta leaves were separated by gel permeation chromatography and chemically characterized. The oxidative stability of microencapsulated linseed oil (MLO) with antioxidants was evaluated in storage conditions at 25°C for 40 days. The antioxidant effects of the polyphenolic fractions and commercial antioxidants (BHT and trolox) on microencapsulated oil were evaluated by the value of conjugated dienes, peroxide, and p-anisidine. In the initiation step of the oxidation, no significant oxidation delay (p>0.05) in MLO containing fractions F6, F8, or BHT and trolox was observed. However, in the termination step of the oxidation, the addition of fractions F6, F8, and BHT and trolox decreases significantly (p ≤ 0.05) the rancidity in MLO. Furthermore, the results of this study demonstrated the importance of the addition of natural antioxidants such as fractions of murta leaf extract in microencapsulated linseed oil to increase its resistance to oxidation. Practical applications: For incorporating linseed oil, a source of omega-3 fatty acids, in the diet it is necessary to protect it against oxidative rancidity, the main cause of deterioration that affects food with a high unsaturated fat content. Microencapsulation is effective in retarding or suppressing the oxidation of unsaturated fatty acids and natural plants extracts are effective in inhibiting the lipid oxidation of microencapsulated oil. The use of process technology and a natural additive is expected to increase storage stability and enable its use in dry foods such as instant products. Linseed oil can be used in human nutrition as well as in animal feed as a replacement for fish oil.

The presence of a right-atrium thrombus is considered as an unusual form of thromboembolic disease, with a prevalence of 10-18%. Most of them are located in the right-atria. Its mortality is about 45%. Echocardiography is very important to detect them and to control the effectiveness of the treatment, which can be either conservative or surgical. We present a case of a man to show the importance of echocardiography in this pathological diagnosis, what is essential for a right-treatment.