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In this paper we present a further step in the implementation of a physical phantom designed to generate sets of "true" independent reference data as requested by TG-186, intending to address and mitigate the scarcity of experimental studies on brachytherapy (BT) validation in heterogeneous media. To achieve this, we incorporated well-known heterogeneous materials into the phantom in order to perform measurements of 125I dose distribution. The work aims to experimentally validate Monte Carlo (MC) calculations based on MBDCA and determine the conversion factors from LiF response to absorbed dose in different media, using cavity theory. The physical phantom was adjusted to incorporate tissue equivalent materials, such as: adipose tissue, bone, breast and lung with varying thickness. MC calculations were performed using MCNP6.2 code to calculate the absorbed dose in the LiF and the dose conversion factors (DCF). The proposed heterogeneous phantom associated with the experimental procedure carried out in this work yielded accurate dose data that enabled the conversion of the LiF responses into absorbed dose to medium. The results showed a maximum uncertainty of 6.92 % (k = 1), which may be considered excellent for dosimetry with low-energy BT sources. The presented heterogeneous phantom achieves the required precision in dose evaluations due to its easy reproducibility in the experimental setup. The obtained results support the dose conversion methodology for all evaluated media. The experimental validation of the DCF in different media holds great significance for clinical procedures, as it can be applied to other tissues, including water, which remains a widely utilized reference medium in clinical practice. [ABSTRACT FROM AUTHOR]

In this paper we present a phantom designed to provide conditions to generate set of "true" independent reference data as requested by TG-186, and mitigating the scarcity of experimental studies on brachytherapy validation. It was used to perform accurate experimental measurements of dose of 125I brachytherapy seeds using LiF dosimeters, with the objective of experimentally validating Monte Carlo (MC) calculations with model-based dose calculation algorithm (MBDCA). In addition, this work intends to evaluate a methodology to convert the experimental values from LiF into dose in the medium. The proposed PMMA physical phantom features cavities to insert a LiF dosimeter and a 125I seed, adjusted in different configurations with variable thickness. Monte Carlo calculations performed with MCNP6.2 code were used to score the absorbed dose in the LiF and the dose conversion parameters. A sensitivity analysis was done to verify the source of possible uncertainties and quantify their impact on the results. The proposed phantom and experimental procedure developed in this work provided precise dose data within 5.68% uncertainty (k = 1). The achieved precision made it possible to convert the LiF responses into absorbed dose to medium and to validate the dose conversion factor methodology. The proposed phantom is simple both in design and as in its composition, thus achieving the demanded precision in dose evaluations due to its easy reproducibility of experimental setup. The results derived from the phantom measurements support the dose conversion methodology. The phantom and the experimental procedure developed here can be applied for other materials and radiation sources. [ABSTRACT FROM AUTHOR]

The heat transfer process during the freezing of 600 kg of fruit juice model solutions in common containers (boxes, buckets and metallic drums), and different settings in a freezing tunnel, was studied. The air velocity was measured at several points in the entire tunnel. Thermocouples were installed to monitor the temperature profiles within the solution, at the packaging surface and cooling air. To measure the experimental effective heat transfer coefficients conventional temperature measurements with thermocouples and infrared thermography technology were used to map the distribution of the coefficients throughout the surface. Energy consumption involved in each configuration was evaluated. The higher velocities occurred at greater height (above the stacking and drums), being possible to verify the existence of preferential airflow pathways near the door and at the tunnel bottom. The highest air velocities observed were 2.85 m s −1 ; 2.72 m s −1 , and 2.62 m s −1 for drums, boxes and buckets, respectively. The movement of the freezing front has begun from the outermost containers toward those located in the center of the stacks and the average freezing time was 51 h (plastic boxes), 55 h (plastic buckets) and 102 h for metal drums. The energy consumption for drums has been almost the double when comparing with buckets and boxes. The distribution of the local convective heat coefficients throughout the freezing process was not constant. Variations and different intensities of scatter were observed for the different packaging configurations and for the different periods during the freezing process (precooling, phase change and tempering). Thermal imaging technology proved useful in the study of heat transfer coefficients, allowing their complete mapping on the surface of the packaging, without the necessity of direct contact with the product. [ABSTRACT FROM AUTHOR]

Melatonin is a potential therapeutic intervention for improving sleep quality in people with autistic spectrum disorder (ASD). We investigate the effect of using melatonin as a sleep disorder treatment in people with ASD. Interventionist studies were searched in seven databases. A total of 595 references were identified, 15 of which were eligible for the systemic review and meta-analysis. Melatonin use presented a positive effect on total sleep time (standardized mean difference- SMD = 0.78; 95%CI = 0.35; 1.21; I2 = 91%), on sleep latency (SMD = 1.23; 95%CI = 0.35; 2.11; I2 = 94%), and on sleep efficiency (SMD = −0.70; 95%CI = −1.23; −0.16; I2 = 91%) when comparing the intervention group with the placebo/control group via the global analysis. According to the global analysis, the wake after sleep onset and night awakening parameters were not statistically significant. Melatonin has possible efficacy over total time, latency, and efficiency sleep parameters. • Melatonin is a potential therapeutic for improving sleep quality in autism. • Melatonin use improves total sleep time, sleep latency and sleep efficiency. • Using melatonin on sleep disorders in people with ASD presents good tolerability. • Prolonged-release melatonin is better for maintaining sleep. [ABSTRACT FROM AUTHOR]

In this report, a process for hydrocolloid extraction from Pereskia aculeata Miller (Barbados gooseberry), popularly known in Brazil as Ora-pró-nóbis (OPN), was developed. In the process, several operations, such as extraction, pressing, filtration, precipitation, grinding and drying, were required. The independent variables evaluated to determine the optimum extraction conditions were the ratio of water:raw material and the extraction temperature. The significant results at each stage were analyzed using the response surface method. The conditions that presented the highest precipitate yield, highest pH value, highest hue value (clear product), highest filtrate viscosity and minimum flow rate value were a water:raw material ratio of 2.46–3.70 L/kg and an extraction temperature between 54.6 and 80 °C. Using the optimized process, gums were prepared at different concentrations and the centesimal composition, mineral content, viscosity and emulsion formation capacities were analyzed. The stability of these emulsions was evaluated at room temperature and at 80 °C. The emulsion formation capacity of the product was verified as being proportional to the increase of the powder concentration. The OPN gums obtained at a solution concentration of 1 g/100 mL presented an emulsion formation capacity of 83%, and the increase in temperature reduced emulsion stability. The powdered product obtained was found to be close to yellow in color with high protein content and with functionalities that can be used in the food industry. [ABSTRACT FROM AUTHOR]

Abstract: This paper investigates the extent of socioeconomic inequalities in antenatal care use and related medical procedures in Brazil and India, which represent transition economies with contrasting geographical and sociocultural composition and health care provision. Concentration indices and regression analyses applied on recent Demographic Health Survey data reveal high and proportionate distribution of antenatal coverage in Brazil, whereas the Indian case present problems of both scale and equity. Inequalities in access to four or more antenatal visits are significantly pronounced in India, and in Brazil the differences are significant only for those who had six or more visits. Brazil''s universal healthcare model which proved effective in promoting equitable distribution of antenatal care could be implemented in India. Future interventions should emphasis quality of care in monitoring essential antenatal services especially targeting the poor and deprived communities. [Copyright &y& Elsevier]

• 52 Leptospira isolates recovered from cattle raised in the Brazilian Amazon were characterized. • The isolates belonged to different species and serogroups. • Strains from the Sejroe serogroup were isolated for the first time in Brazilian Amazon. • Some genotypes may represent new strains not yet characterized. In Brazil, there have been few leptospires isolated from cattle, especially in the Amazon, implying that the epidemiology of the disease in this region is still largely unclear. In a previous study, 52 Leptospira isolates were obtained from urine of cattle raised in the Brazilian Amazon and, to achieve a greater understanding of Leptospira infection in cattle of this region, the present study aimed to serologically and molecularly characterizes all these isolates. The laboratory assays used were the microscopic agglutination test (MAT) adopting a panel of polyclonal antisera against Leptospira spp. for serogrouping the isolates, DNA sequencing (secY) and multiple locus variable number tandem repeat analysis (MLVA). The isolates belonged to five species: 20/52 were identified as L. borgpetersenii (38.5 %); 18/52 as L. kirschneri (34.6 %); 9/52 as L. santarosai (17.3 %); 3/52 as L. noguchii (5.8 %) and 2/52 as L. interrogans (3.8 %). With serogrouping, nine different serogroups were detected, with a high frequency of the Sejroe serogroup. MLVA showed that all L. borgpetersenii isolates had a profile compatible with serovar Hardjo; moreover, the other isolates demonstrated a diversity of patterns, and some of them may represent strains not yet characterized. In the Brazilian Amazon, the leptospires circulating in cattle revealed the unique aspects of infections in this area which, in addition to a variety of strains, were characterized by a high frequency of the Sejroe serogroup, highlighting the serovar Hardjo, which has not been reported in other regions of Brazil. [ABSTRACT FROM AUTHOR]