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Radiation risk perception must be studied by communication and radiological protection specialists, taking account of engineering, social and cultural variables. An anonymous and voluntary survey was peformed to enquire about the radiation risk perception among university students and radiological protection experts from Argentina, and to become aware of how it is perceived compared to other health risks. A fifteen-question dedicated questionnaire was designed including socio-demographic variables and questions about work environment, risk perception and risk communication. A five-point Likert-type scale was used for most of the questions. Surveyed people were asked to compare radiological risks in medicine with other risks (i.e.: smoking, sports, leisure activities, stress). The research involved 10 (38.5%) experts, 25 (45%) physics and engineering students and 40 (100%) bio-images production bachelor students. The results were analysed based on the professional or academic background. Although participants considered the radiation exposure in medicine as a low-risk activity, the results showed a disagreement about the radiation risk perception in particular situations (i.e.: living near a nuclear power plant, training in radiological protection while at college) and about radiation risk communication strategies. There is neither right nor wrong risk perception; however, a lot of work must be done to build an agreement between radiological risk perception and risk assessment due to radiation exposure in medicine. It should include working on the design of public policies focused on radiological protection training for health staff and clinical research training for medical physicists and radiological protection specialists, while strengthening communication skills and channels.

Mammography is a radiation medical exam, which makes detection of mammary microcalcifications possible at an early stage. The dose received by the patient’s breast is known as the average glandular dose, which is considered a quality control indicator. Estimation of this parameter implies knowing the effective energy of the x-ray beam delivered. This is the case when thermoluminescent dosimetry is the method of choice. The algorithm developed to discriminate the x-ray energy the mammography patient has been exposed to while undergoing routine procedures, applies two thermoluminescent dosimeters, one of them filtered by a 1 mm thick aluminum layer. The effective energy of the x-ray beam and the correction factor are obtained by knowing the relation between the filtered and non-filtered dosemeters readout. This algorithm was then used to estimate the average glandular dose following the IAEA TRS 457 protocol. The dose values computed were compared with the international diagnostic reference levels suggested by the technical literature.

ABSTRACT: Sinonasal neoplasms represent approximately 1% of all neoplasms and represent a major challenge for treatment. The treatment of nasal tumors must be local, and radiotherapy can be a good option in these cases. This study evaluated the therapeutic response of canine sinonasal neoplasms to megavoltage radiotherapy, and consequently, its influence on the survival and quality of life of these animals. We included 26 dogs with sinonasal neoplasms through histopathological and cytological examination. Dogs were treated with radiotherapy at total doses of 42-54 Gy (for carcinomas) and 45 Gy (for sarcomas) in 15-18 fractions of 2.8-3.0 Gy. Tumor staging was performed based on skull tomography. The most frequent clinical signs of sinonasal neoplasms were sneezing, nasal noise, and epistaxis. Acute side effects were mild and more frequent. Survival was evaluated based on tumor stage, obtaining a mean overall survival of 329 days (95% confidence interval, 229-428) and a median of 252.5 days. The survival time in animals in stage T3/T4 was significantly shorter than that in those in stage T1/T2 (P < 0.05). Moreover, 86.4% of the treated animals showed clinical improvement. Radiotherapy was well tolerated by dogs and effective in controlling sinonasal neoplasms.

ABSTRACT This study aimed to estimate the heat flux through sensitive mechanisms and respiratory evaporation of Japanese quails kept in thermoneutral and warm environments, using simple environmental and physiological measures. 192 nine-week-old quails were used, distributed in a completely randomized design at two temperatures (T1 = 24°C and T2 = 32°C), with 12 replicates of eight birds each, with an experimental period of 63 days, divided into three 21-day periods. Physiological measurements of respiratory rate (RR), cloacal temperature (TC), and body surface temperature (TS) were measured twice a week. The behavior of the energy balance in the climatic chambers was obtained using the total thermal energy exchanges per unit surface area of the birds, derived from the sum of sensible (radiation and convection) and latent heat exchanges. Respiratory rate (P

Copyright of Arquivos de Ciências da Saúde da UNIPAR is the property of Associacao Paranaense de Ensino e Cultura and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Nativa is the property of Revista Nativa and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

ABSTRACT The great advances in using new devices and imaging systems in surgeries aim to reproduce an ideal and safe scenario for the surgeon, the team, and the patient. New systems and devices are constantly available to demonstrate and facilitate intraoperative navigation, thereby reducing errors and avoiding complications for the patient and staff. This study evaluates and compares using the O-arm® system and radioscopy in the freehand technique in spine surgeries. For this, searches were conducted in PubMed and Embase for randomized and non-randomized studies using the O-arm® system and radioscopy in spine surgery. Twenty-four studies were included and compared regarding procedure time, accuracy of implant positioning, effective radiation dose, safety, and efficacy. In one study, the O-arm® group showed a shorter surgical time when compared to the freehand technique (222.5 min. [SD=38.0] vs. 255.2 min. [SD=40.3], p=0.011, respectively). In two studies, the freehand technique resulted in a lower effective radiation dose for patients. In 12 studies, a higher incidence of complications was observed among patients undergoing surgery with the freehand technique. It was concluded that using the O-arm® is associated with a reduction in malposition of implants and more safety for instrumented procedures. Still, no evidence exists that its use can result in less surgical time. Level of Evidence I; Diagnostic Analysis and Studies, Investigation of a Diagnostic Test.

Copyright of GeSec: Revista de Gestao e Secretariado is the property of Sindicato das Secretarias e Secretarios do Estado de Sao Paulo (SINSESP) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction – Surface guided radiotherapy (SGRT) is a technique that uses technology in the 3D detection of the patient’s surface, which helps the radiation therapists in the daily repositioning and monitoring of intra and interfraction movements of the patient. It is a non-invasive technique and does not use ionising radiation. Objectives – It is intended to study if the SGRT technique could replace the use of skin markers and the use of verification/Image- -guided radiation therapy (IGRT) imaging protocols, without compromising the reproducibility of the treatment. Methods – A systematic review was performed in the Scopus and MEDLINE databases, where articles published in the last five years were analysed. After combining the search terms and according to the inclusion and exclusion criteria, ten articles were included in this review. Results/Discussion – The SGRT technique reduced positioning deviations compared to positioning based on skin markers. On the other hand, it allows a dose reduction resulting from IGRT verification, due to the lower frequency of its use, when combined with SGRT. Conclusion – SGRT proved to be feasible in ensuring accurate positioning when compared to conventional repositioning based on the conjugation of skin markers and lasers. A significant reduction in intrafraction and interfraction errors was also observed. However, it was not considered sufficiently feasible to replace IGRT to its full extent. IGRT still has an important role in confirming anatomical positioning and in monitoring PTV and adjacent organs. [ABSTRACT FROM AUTHOR]

The teaching of medical physics evolves every year in Brazil. The need for didactic and interactive methods grows proportionally, aiming at greater motivation and better learning on the students' behalf. In undergraduate courses in medical physics in Brazil, the discipline of radiation physics is fundamental for the student's professional formation. The purpose of this work is to utilize the TOPAS Monte Carlo to simulate experiments that allow the discussion over covered contents on the discipline of radiation physics related to medical physics. The tool may be used by teachers to minister this discipline and by students that may want to deepen their knowledge and be introduced to the Monte Carlo method. Initially, it was done the code validation for the photon spectra used through the comparison with literature. Therefore, it was possible to elaborate the input archives and perform the output archives data analysis for different irradiation setups covered by the academic community in order to evince factors influence, such as: curves statistics by the number of histories; irradiation field size; homogeneous and heterogeneous medium; different incident beams natures. The obtained results show that the performed simulations allow a correct and dynamic analysis of the radiation interaction processes with matter approached in radiation physics. [ABSTRACT FROM AUTHOR]

The State of Alagoas dedicates 1o,95% of its area to the cultivation of sugar cane (Saccharums sp.). Soil heat flux (SHF) is a crucial component of net radiation (Rn), which also varies due to changes in vegetation cover. This experiment was carried out in an area of experimental sugar cane cultivation in the municipality of Rio Largo (09°28'03" S, 35°49'49" W) from November 2017 to November 2018. The aim was to characterize SHF and Rn under different degrees of soil vegetation cover in the Coastal Tablelands of the Alagoas state, Brazil. Net radiation components were measured using a Kipp and Zonen CNR1 net radiometer, whereas SHF was measured using three HFT-3 plates (REBS, Campbell Scientific Inc., USA), which were installed at a depth of 0.05 meters. The predominant atmospheric transmittance (Kt) classification was partly cloudy (54.70%). Precipitation, along with cloudiness, incident solar radiation, and land cover, influenced the seasonal cycle of net radiation (Rn) and soil heat flux (SHF). On average, the removal of vegetation cover had a negligible impact on Rn, whereas it led to a 437% increase in SHF during the day and a 240% increase during the night. [ABSTRACT FROM AUTHOR]

Copyright of Revista de Atencao Primaria a Saude is the property of Revista de Atencao Primaria a Saude and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Nuclear energy divides public opinion with its “good” and “bad” applications. Almost immediately after the discovery of radiation, radioactive elements purified by the Curies were used in health treatments, but with the nuclear bombs of Hiroshima and Nagasaki, the subject was marked by bad public opinion, being related to death and destruction. Nowadays, nuclear physics is used in many important fields, such nuclear medicine for the diagnosis and treatment of various types of diseases, but the prejudice and lack of knowledge of the general public has not yet improved its “fame”. This work proposes to change a little of this paradigm. Through a questionnaire, the public perception of radioactivity was evaluated. The most important result obtained is that the public is interested in learning about radiation and nuclear energy and is willing to change their negative views.

ABSTRACT Objective: to assess the need of computed tomography (CT) for the definition of management in pediatric abdominal trauma. Methods: observational retrospective study with patients under 18 years old victims of blunt or penetrating abdominal trauma that underwent CT of the abdomen and pelvis at admission. We evaluated CT scan findings, indications and management. We calculated the sensitivity, specificity, positive predictive value and negative predictive value of clinical variables and energy of trauma for findings on CT. Results: among the 236 patients included in our study, 72% (n=170) did not present abnormal findings on CT. It was performed surgical treatment in 15% (n=10), conservative treatment in 54,5% (n=36) and 27% (n=18) did not receive treatment for abdominal injuries. In the assessment of CT indications, 28,8% (n=68) presented no justifications. In this group, 91% (n=62) did not show any abnormal findings. Among the six patients with positive findings, half were selected for conservative treatment, while the rest did not need any treatment for abdominal injuries. The presence of abdominal pain, hemodynamic alterations and high energy blunt trauma had low positive predictive values when isolated, whereas the negative predictive values were higher. Conclusion: although CT is necessary in some instances, there is a possible high number of exams that did not make any difference in the management of the pediatric population.

Abstract Urbanization, pollution and the modification of natural landscapes are characteristics of modern society, where the change in human relations with the environment and the impact on biodiversity are environmental determinants that affect the health-disease relationship. The skin is an organ that has a strong interface with the environment and, therefore, the prevalence patterns of dermatoses may reflect these environmental changes. In this article, aspects related to deforestation, fires, urbanization, large-scale agriculture, extensive livestock farming, pollution and climatic changes are discussed regarding their influence on the epidemiology of skin diseases. It is important that dermatologists be aware of their social responsibility in order to promote sustainable practices in their community, in addition to identifying the impacts of environmental imbalances on different dermatoses, which is essential for the prevention and treatment of these diseases.

ABSTRACT In this study, we present computational procedures to solve problems for the maximization of production and net income from crops or trees in a randomly generated agroforestry system with limited inputs, based on the Logarithmic Barrier Method. The results obtained showed numerical consistency for viability and optimality of both problems in the agroforestry scenarios tested, as well as promoted conditions to solve the problems with real data.

Monte Carlo (MC) simulation can be used in teaching the physics of ionizing radiation with applications in medical physics. However, the free MC codes available are not user-friendly for new and inexperienced users, limiting their use as an educational tool. This study focuses on the development of a user-friendly graphical interface for MC simulations with a focus on learning the interaction of ionizing radiation applied to Medical Physics. The interface is an executable file developed in Python 3.9. The interface serves as a frontend for the simulations performed by the PENELOPE v. 2014 code with the penEasy v. 2015 extension. Two types of simulations are available: (i) Particle tracking and (ii) Dose deposition. The results obtained in case (i) are presented graphically as three figures that show the trajectory of electrons, photons and positrons, respectively. For case (ii), the result is the dose as a function of the depth of a box-shaped volume. In summary, this interface, with simple geometry and fast simulations, in an interactive environment, offers a wide range of possibilities for understanding the interaction of radiation with matter, which is the basis of medical physics. [ABSTRACT FROM AUTHOR]

The article describes the reports of expeditions to Guarapari and other publications (1956-1967) written by Father Francisco Xavier Roser S.J. with the aim of characterizing his scientific production on environmental radiation We try to elucidate his scientific network. Our contribution also discusses the radiometric surveys of areas with high soil radioactivity, the dosimetric exams of the local population, and the measurements of atmospheric radioactivity carried out on the south coast of Espírito Santo. Finally, we explain the techniques, the research methods employed by the group of scientists, gathered around Roser, the research results and the inter-institutional collaborations. [ABSTRACT FROM AUTHOR]

Abstract Background Neuroimaging is widely used for diagnosis and treatment of stroke. However, little is known about whether the radiation doses received by patients comply with international safety guidelines. Objectives The aim of this study was to evaluate the effective radiation dose received while in hospital for stroke and analyze its safety according to current guidelines. Methods This cross-sectional study included 109 patients who were hospitalized and diagnosed with ischemic stroke. The National Institutes of Health Stroke Scale was used to evaluate stroke severity, the Bamford clinical classification was used for topography, and the TOAST classification was used for etiology. The computed tomography dose index and size-specific dose estimates were used to calculate the effective radiation dose (ERD) received while in hospital. A Mann-Whitney test was used to compare the ERD received by thrombolysed and non-thrombolysed patients. Non-parametric statistics were used to analyze the data with a 95% confidence interval. Results During the study period, the median ERD received was 10.9 mSv. Length of stay was not associated with radiation exposure. No differences were demonstrated in ERD according to stroke etiology or Bamford clinical classification. Patients who had CT perfusion (only or in addition to CT or angiotomography) received the highest ERD (46.5 mSv) and the difference compared to those who did not (10.8 mSv) was statistically significant (p

Much of the biological effects caused by radiation appear due to prolonged exposure. Each cell in the organism has it own tolerance threshold, in this way the dangers may appear in different degrees. The effects of ionizing radiation in the tissues depends of the type of radiation and the tissue that will be infiltrated. The effects ranging from hematopoietic system, which can course with anemia, to nervous central system, which can result in death for collapse, for example. Each imaging method emits a different amount of radiation, thus, radiologist’s physicians and techniques in this area are trained to limit the patient exposure for a safe dose to make the correct diagnosis. If the radiation is used indiscriminately, the excess of radiation exposure may have a carcinogenic effects and mainly teratogenic in pregnant women. Regardless of the harm caused by exposure to radiation its benefits are important for the diagnosis of many diseases and to the advancement of medicine if used consciously and within regulatory standards. This literature review aims to evaluate the impact of radiation on patients undergoing imaging exams. [ABSTRACT FROM AUTHOR]

In order to study the safety aspects connected with the permanent increase of the maximum steady state power of the IPR-R1 Triga Reactor of the Nuclear Technology Development Center (CDTN), experimental measurements were done with the reactor operating at power levels of 265 kW and 105 kW, with the pool forced cooling system turned off. A number of parameters were measured in real-time such as fuel and water temperatures, radiation levels, reactivity, and influence of cooling system. Information on all aspects of reactor operation was displayed on the Data Acquisition System (DAS) shown the IPR-R1 online performance. The DAS was developed to monitor and record all operational parameters. Information displayed on the monitor was recorded on hard disk in a historical database. This paper summarizes the behavior of some operational parameters, and in particular, the evolution of the temperature in the fuel element centerline positioned in the core hottest location. The natural circulation test was performed to confirm the cooling capability of the natural convection in the IPR-R1 reactor. It was confirmed that the IPR-R1 has capability of long-term core cooling by natural circulation operating at 265 kW. The measured maximum fuel temperature of about 300 oC was lower than the operating limit of 550 oC. It has been proven that without cooling in the primary the gamma dose rate above reactor pool at high power levels was rather high.

Hydrogels are cross-linked polymer networks, which are of interest in biomedical applications such as drug delivery system. To achieve successful results in this kind of application it is essential to understand the diffusion mechanisms which are generated in the hydrogel during the swelling process. For this reason, this work consists in carrying out an analysis of the swelling kinetics in hydrogels elaborated through gamma radiation and the combination of gamma radiation with thermal cycling processes. The hydrogels were synthesized using biocompatible polymers irradiating their solution at different doses. A swelling test was performed and the diffusion coefficient and the diffusional exponent were calculated, making an analysis of the kind of diffusion mechanism in the hydrogel matrix. This test showed that the higher radiation absorbed used to get the gels, the lower the swelling percentage, as well as the diffusion coefficient of the water molecules in the hydrogel. The results of the kinetic analysis showed an anomalous diffusion mechanism for the gels obtained at 25 kGy. For those gels of 30 kGy, the diffusion was Fickian. Finally since those gels of 35 kGy was not possible to classify it according to the Fick's law of diffusion. Furthermore, we could observe that the hydrogels that had been obtained by thermal cycling and by irradiation had higher swelling percentages compared to those that were only cross-linked by irradiation. This analysis allowed us to understand the intrinsic behavior of the polymer / solvent mesh system at different doses and under two different crosslinking conditions.

All tissue banking activities are depending on tissue donors. The donor rate is still low in Argentina, and the tissue demanding is still not fulfilled. For this reason, tissue engineering has become a necessary discipline to be investigated. Our project is conducted to obtain a 3D resorbable printed scaffold seeded with mesenchymal stem cell (MSC), to conduct real bone. We produced three polylactic acid (PLA) filaments with different loads of hydroxyapatite (HA): 3%, 5% and 10%. The mixtures were homogenous and the three filaments were suitable for 3D printing and were used to print 3D scaffolds samples. The scaffolds were irradiated with range doses of 15 kGy to 25 kGy for sterilization purposes and to evaluate if the degradation polymer rate is regulated with the irradiation dose. The elaborated filaments were optimally printable. In addition they turned out to be not cytotoxic (cell viability greater than 70%) and whit good cellular adherence. In this way, our biomaterial seems to be good for scaffolds for bone replacement.

ABSTRACT Objective: To evaluate the radiation dose received by staff in spine surgeries, including those who are not considered occupationally exposed workers. Methods: All spinal surgeries performed in the same department during a period of 12 months were evaluated with regard to the exposure of surgeons, scrub nurses, and auxiliary personnel working in the operating room to radiation from C-arm fluoroscopy. Radiation was measured by 15 film badge dosimeters placed on the professionals’ lapels, gloves, and room standardized sites. The films were analyzed in the dosimetry laboratory by collections per period. Results: During the 12 months, 81 spinal surgeries were performed by the same team, with surgical times ranging from 1 to 6 hours. The total radiation dose ranged from 0.16 mSv to 2.29 mSv depending on the dosimetry site. The most exposed site was the wrist of the main surgeon. Conclusion: The results showed that in the spinal surgeries in our setting, the radiation doses are low and within legal limits. Nevertheless, constant training of professionals is essential for radiation protection of medical staff and patients. Level of evidence I/b, exploratory cohort study.

The analysis of variance is the statistical test most used for comparison of three or more means simultaneously. Its application requires, however, the compliance to some assumptions, with main emphasis on normality of the data and homoscedasticity of variances. When such requirements are not met, one of the alternatives is the data transformation to enable the continuity of the experimental evaluation. With the proposition of the Tukey’s data transformation system, understood as a power transformation system, i.e. the application of nth root on a data set (X⅟n) this statistical procedure has methodologically evolved to ensure such solutions. In the present research we proposed a complement to this system, denominated here as transformation in four steps, with inclusion of two hypothesis tests to evaluate normality and homoscedasticity. This was applied on experimental data to evaluate the amount of radiation available at soil level within stands of Acacia mearnsii De Wild. We have proposed a model for data transformation to simultaneously obtain homoscedasticity and normality. The methodology was appropriate to ensure these two statistical aspects on the experimental data, allowing comparison of eight treatments by conventional analysis of variance. Index terms: Analysis of variance, homoscedasticity, normality.

It is shown that, although Einstein and Compton's arguments were fundamental for the acceptance of the corpuscular character of electromagnetic radiation, there are other approaches able to explain the photoelectric and Compton effects, without using the photon concept. In this context, radiation is treated as a classic electromagnetic wave that interacts with the electron. [ABSTRACT FROM AUTHOR]

In this article, we investigate the dynamics of a charged particle when subjected to an electric field generated by two dielectric and homogeneous disks. We analyzed the construction of the motion equation for the accelerated charge, which in the linear approximation of the electric force results in a Simple Harmonic Oscillator (SHO). Subsequently, the Abraham-Lorentz radiation force is incorporated into the motion equation because the accelerated movement of the load results in the emission of energy radiation and, in this situation, behaves like a Damped Harmonic Oscillator (DHO). And we calculated Larmor's radiation power for this damped particle motion. [ABSTRACT FROM AUTHOR]

Introduction: The action of ultraviolet rays can cause several damages to the human being, being skin cancer and photoaging the most studied. Ultraviolet rays facilitate gene mutations and suppress the skin's immune system. Objective: to carry out a literature review on the characteristics of sunscreens and their mechanism of action. Development: The application of photoprotectors as a direct method of protection has been widely discussed in the literature, being suggested for the care of all skin neoplasms. Intrinsic factors influence the existence of these or not, but the geographic location and some precautions such as the use of sunscreen and the appropriate time to receive the incidence of sunlight contribute directly to the appearance or not of cancer and photoaging. Final considerations: the present study made it possible to verify the relationship between the increased incidence of skin cancer cases and other related problems caused by excessive sun exposure, with sunscreen being the main barrier to prevent these damages. [ABSTRACT FROM AUTHOR]

Copyright of Latin-American Journal of Physics Education is the property of Latin-American Physics Education Network and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This article deals with "radiação" or radiation as a process that creates bond and distance between people and spiritual entities -- souls, spirits, and "caboclos" -- and between these entities themselves. Drawing on ethnographic research conducted in Andaraí, a city in the Chapada Diamantina region, located in the northeast of Brazil, it presents a range of variations around the radiation in two contexts: in the "jarê", an African-based religion, and in the mourning ritual called "terno das almas". The radiation is often defined as a stage prior to possession, being an experience underlined by ambivalence and uncertainty of the entities' presence in people's bodies and practices. In this paper, I will argue that the radiation experience can also be thought of as a way of being in a relationship with these entities, demanding attention, knowledge, and zeal. [ABSTRACT FROM AUTHOR]

Childhood cancer is currently one of the leading causes of illness in children. The diagnosis of a posterior fossa tumors triggers a series of invasive treatments that abruptly alter the biopsychosocial context in which the child is adapted. Therefore, cognitive deficits appear as direct consequences of this process and significantly reflect on poor school performance and intellectual impairments. Considering these observations, the present work aims to investigate, through an integrative literature review, the advances in scientific production about the neuropsychological impact, especially the late effects of treatment, involved in the diagnosis of children with pediatric tumors of the posterior fossa. Articles indexed in the MEDLINE databases (PubMed) were searched; LILACS; SciELO (Scientific Electronic Library Online), Google Scholar and Cochrane Library were searched. 163 articles were found and analyzed using their title and abstract. After meeting the inclusion and exclusion criteria, a total of 55 articles were read in full version and finally a total of 22 original articles were selected for interpretation, discussion and presentation of data. It was observed difficulties of consensus in the literature as to which specific cognitive skills are impaired, despite consistent global intellectual decline and evidence of changes in brain white matter that are commonly related to processing speed. In addition, there are important risk factors for low intellectual performance, such as: early age at diagnosis, sex, radiotherapy treatment or combined with chemotherapy, post-surgical neurological complications and ataxia. Finally, it is concluded that there is a implicite necessity for formulating a more consensual methodology in the literature, through more careful analysis in the inclusion of patients in the studies and especially considering the risk factors indicated by the literature. It is also suggested the implementation of longitudinal neuropsychological assessments in order to identify both preoperative effects of tumor growth and late effects of cancer treatment, which seem to extend even 10 years after the child's clinical stabilization. Moreover, with these advances, it can be possible to obtain sufficient data to develop strategies for specific cognitive interventions that can promote better academic and intelelectual performance, as well as the children's quality of life adaptation, both during and after cancer treatment. [ABSTRACT FROM AUTHOR]

The Brazilian solar energy potential presents an annual average considerably high compared with Germany, which receives 40% less radiation than the least sunny place in Brazil and, even so, is at an advanced stage of research and facilities. The cooperation between Brazil and Germany promotes important results for the development of solar energy in the country. [ABSTRACT FROM AUTHOR]

Copyright of Ciencia, Cuidado e Saude is the property of Universidade Estadual de Maringa and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Anuario do Instituto de Geociencias is the property of Universidade Federal do Rio de Janeiro, Instituto de Geociencias and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abdominal aortic aneurysm (AAA) is a cumbersome pathology, with catastrophic consequences when not properly diagnosed and treated. Nowadays, EVAR became an established treatment option for AAA, with better perioperative outcomes when compared to open surgery, and is quickly gaining a position of preference among the patients. However, the occurrence of endoleaks is described as the most common adverse event associated to EVAR. Consequently, we review the definition and classification of endoleaks as well as their potential risks and management. Nonetheless, according to the current follow-up protocols of ESVS, this technique requires an extensive imaging follow-up, usually by means of computed tomographic angiography (CTA), which carries increased economic cost and leads us to discuss related great radiation hazards. Concerning the latter, we also review the selected studies and we concluded that the first month CTA is the single most important imaging exam for patients’ prognosis and, once no complications are found, other reviewed imaging follow-up strategies should be undertaken to minimize radiation exposure and yet further risks for the patients. Therefore, this article establishes an overview about the current evidence and future strategies on EVAR imaging follow-up.

Ionizing radiation has been applied in several areas of knowledge, among them the study of the radiomodifier activity of natural substances. These substances can modify the cellular response to the damage induced by the radiation. Therefore, this work aimed to evaluate the radiomodifier action of Pityrocarpa moniliformis extract on Biomphalaria glabrata embryos exposed to 60Co gamma radiation. Initially, toxicity tests were performed on the extract against the B. glabrata embryos for the choice of concentration that did not cause death and embryonic malformation. Then, the antioxidant activity of the P. moniliformis extract with flavonoids and phenolic compounds was evaluated by means of the ABTS method. To evaluate the radiomodifier activity of the extract, embryos were selected in the blastula stage and irradiated with 7.5 Gy in a 60Co source (gammacell-Co60). Then, the embryos were exposed for 24 h to the extract of P. moniliformis at a concentration of 250 μg/mL. The results showed that the extract of P. moniliformis presents flavonoids and enzymatic inhibition by ABTS, which demonstrates the presence of antioxidant compounds. However, the tests of the radiomodifier activity did not present radioprotective effect for embryos exposed to ionizing radiation.

The micronucleus assay is an important technique used to evaluate genotoxic damage of chemical or physical agents (as ionizing radiations) on cells, based on quantification of cells bearing micronuclei, which are fragments derived from damage (breakage) of the DNA. Currently, this technique was updated to an automated approach that relies on plasma membrane dissolution to analyze fluorescent dye-labelled nuclei and micronuclei by flow cytometry. Cell suspensions were irradiated in PBS by a 60Co source in doses between 0 and 16 Gy, and incubated by 72h. Cell membranes were lysed in the presence of SYTOX Green and EMA dyes, so EMA-stained nuclei could be discriminated as from dead cells, and nuclei and micronuclei could be quantified. Amounts of micronuclei (percent of events) in the samples, were found to be proportional to radiation doses, and could be fitted to a linear-quadratic model (R² = 0.993). Only higher doses (8 and 16 Gy) and positive control could induce relevant increases in micronucleus amounts. The incorporation EMA showed an increase in irradiated cells. Mid- to high doses (4, 8 and 16 Gy) induced reduction of cell proliferation. Experiments showed the suitability of the technique to replace traditional microscopy analysis in evaluation of the effects of ionizing radiations on cells, with possibility to use in biological dosimetry.

Micronucleus assay is a test used to evaluate genotoxic damage in cells, which can be caused by various factors, like ionizing radiation. Interactions between radiation energies and DNA can cause breakage, leading to use chromosomal mutations or loss of genetic material, important events that could be induced in solid tumors to mitigate its expansion within human body. Melanoma has been described as a tumor with increased radio resistance. This work evaluated micronuclei percentages (%MN) in human melanoma cells (SK-MEL-37), irradiated by gamma radiation, with doses between 0 and 16Gy. Cell suspensions were irradiated in PBS by a 60Co source in doses between 0 and 16Gy, and incubated by 48h. Then cell membranes were lysed in the presence of SYTOX Green and EMA dyes, preserving nuclear membranes. Using this method, EMA-stained nuclei could be discriminated as those derived from dead cells, and SYTOX nuclei and micronuclei could be quantified. Micronuclei percentages were found to be proportional to dose, (R2 = 0.997). Only the highest dose (16Gy) could induce statistically significant increase of MN (p

The intracellular production of nitric oxide is studied as a relevant phenomenon in exposure to ionizing radiation. There is evidence of local nitric oxide production in solid tumours. Its effects were observed on the relationship between their presence with tumor progression, linked to the emergence of potential genotoxic or cytotoxic damage, or loss of proliferative capacities of tumour cells. The study evaluated the effects of the administration of aminoguanidine, a selective inhibitor of an isoform of nitric oxide synthase on the frequency of genotoxic damage, loss of clonogenic potential, induction of cytotoxicity and nitrite production after exposure to ionizing radiation in radiotherapeutic doses. Human breast tumor (MCF7) cells were treated with aminoguanidine (1 or 2 mM) and irradiated by gamma radiation at doses between 0.5 and 8Gy. The study used a well stablished technique with some modifications for evaluation of genotoxic damage by frequency of micronuclei in binucleated cells. In cultures treated with 1 mM, we observed increased cytotoxicity and genotoxicity, and reduction of the clonogenic potential of the colonies. Alternatively, 2 mM aminoguanidine produced the opposite effect, apparently protecting cultures from the effects of exposures. The experiments suggested that the administration of aminoguanidine may reduce the in vitro radiossensitivity of tumors due to the increase of the frequency of genotoxic damage.

Physalis peruviana L. is a species of commercial interest belonging to the Solanaceae family, cultivated preferentially in shaded environment, which still has cultivation restricted to small areas in Brazil and therefore requires further studies. Plants are directly affected by environmental factors such as drought, temperature, radiation, among others. These factors affect not only the vegetative organs, but also reproductive structures, which may cause damage to agronomically explored plants. With the need for shading presented by the crop, the present work aimed to characterize the pollen grain and to verify the influence of shade nets used in shading on the morphology of pollen grains of this species. The work was developed at the Lavras Federal University, where three replications of two plants were cultivated under full sun and under shadenets white, blue, red and black. Flower anthesis pollen was collected, processed and photographed by scanning electron microscope (SEM). Polar diameter, equatorial diameter and pollen area were measured in ten pollen grains. The results showed that P. peruviana pollen grains are isopolar, radial, prolato-spheroidal in shape and medium in size. There was also an increase in pollen grain area when cultivated in shading with white shade net and in full sun. [ABSTRACT FROM AUTHOR]

The objective of this study was to measure the intensity of photosynthetically active radiation (PAR), ultraviolet A (UVAR) and ultraviolet B (UVBR) for one year (May to December 2013 and January to April 2014) in Florianópolis. Measurements were performed every Monday, Wednesday and Friday at 1-hour intervals from 10:00 a.m. to 2:00 p.m. The highest intensities of PAR were observed in January, followed by February, November and December. The highest intensities of UVAR occurred from September to February, and for UVBR, from November to February. Taking into account the time, the incidences of PAR showed no statistical difference, UVAR intensities were higher than those of UVBR during all months and at all times. For UVAR the incidence peaks occur at noon, while the UVBR was more constant during measured times. Seasonally, it was noted that the highest indices of PAR, UVAR and UVBR occurred in summer. [ABSTRACT FROM AUTHOR]

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The tomato easily deteriorates post-harvest, even under refrigeration. The aim of this work therefore was to evaluate the effect of levels of ultraviolet radiation (UVC) for different periods of storage, on refrigerated ‘Pitenza’ tomatoes. The fruit were harvested and immediately transported to the laboratory where they were kept at 12 ± 1 °C for 12 hours. The fruit were sorted, and later subjected to levels of UVC radiation: 0 (control), 2.27, 4.54 and 7.19 kJ m-2. They were then stored under refrigeration at 12 ± 1 °C and 90-95% RH for 21 days. Every 7 days for a period of 21 days, an analysis was made of the hydrogen ion potential, ascorbic acid, peroxidase, lycopene and lipoxygenase. The experimental design was completely randomised, in a 4x4 factorial (level x time), with three replications. For enzyme activity, as well as for lycopene and ascorbic acid levels, no interaction was seen between the factors level x time, with a statistical difference only being noted for the level of radiation. By the end, it could be seen that fruits submitted to levels of 2.27 and 4.54 kJ m-2 displayed a positive effect on the quality of the tomatoes from the UVC radiation. = O tomate se deteriora facilmente em pós-colheita, até mesmo quando submetido à refrigeração. Assim, objetivou-se com este trabalho avaliar o efeito de doses de radiação ultravioleta (UV-C) em diferentes tempos de conservação de tomates ‘Pitenza’ refrigerados. Os frutos foram colhidos e imediatamente transportados ao laboratório, onde foram mantidos a 12 ± 1 0C, por 12 horas. Posteriormente, os frutos foram padronizados, sendo submetidos às doses de radiação UV-C 0 (controle); 2,27; 4,54 e 7,19 kJ m-2 e armazenados sob refrigeração a 12 ± 1 oC e 90-95% de UR, por 21 dias. Realizaram-se análises a cada 7 dias, em um período de 21 dias, quanto ao potencial hidrogeniônico, ácido ascórbico, peroxidase, licopeno e lipoxigenase. O delineamento experimental foi inteiramente casualizado, em esquema fatorial 4x4 (dose x tempo), com 3 repetições. Na atividade enzimática, bem como nos teores de licopeno e ácido ascórbico, não foi verificada a ocorrência da interação entre os fatores dose x tempo, somente sendo evidenciada a diferença estatística nas doses de radiação. Ao final, observou-se que os frutos submetidos às doses de 2,27 e 4,54 kJ m-2 demonstraram efeito positivo da radiação UV-C sobre a qualidade dos tomates.

Biodegradable films from whey proteins have a great potential for application on packaging, due to their excellent mechanical and optical properties. However, some processes, such as the use of gamma radiation, can affect the physical, mechanical and color properties of films produced from these proteins. This study aimed to produce biodegradable films from irradiated whey protein concentrate (50 kGy) and evaluate their efficiency for packaging apple. The use of films prepared with irradiated whey proteins was not a good barrier to moisture loss, when subjected to a temperature of 25 ºC and relative humidity of 55 %, but it is a great alternative for color preservation, slowing the browning of apples after cutting.

The article discusses estimates of risks associated with ionizing radiation, especially related to nuclear medicine. The study conducted by the authors quantified the radiation exposure of patients injected with radioisotopes, using a calibrated Geiger-Müller meter. The results showed that the radiation dose values received by patients and the general public are below the limits established by international standards of radiological protection. The article highlights the importance of communicating radiation levels in terms of environmental dose to facilitate public understanding. [Extracted from the article]

Radiation dosimetry for medical and industrial purposes has increasingly evolved over the last few decades with the introduction of various new detectors. Depending on the properties exhibited for radiation dosimetry, some detectors present their applications in a specific area. From a physics point of view, an ideal dosimeter should be able to measure absorbed dose. In this work, synthetic materials based on polybutadiene rubbers (PBR) were proposed as a new class of radiation detectors. The influence of radiation dose on their properties has been investigated for application in radiation dosimetry. The rubber samples were exposed to absorbed doses from 10 Gy up to 250 Gy, using a 60Co Gamma Cell-220 system. Their responses were carried out with a Fourier Transform Infrared (FTIR) Spectrometer to investigate the presence of absorbance peaks. The results suggested the existence of a relationship between the absorbed doses and the absorbance peaks associated with stretching (1300-1200 cm-1), deformation (1450-1340 cm-1) and vibration (1500-1400 cm-1) processes in the material.