Apropriação dos espaços urbanos na infância e na velhice em Brasília (DF) / Occupation of urban spaces in childhood and old age in Brasilia, Brazil / Apropiación de espacios urbanos en la infancia y en la vejez en Brasília, Brasil

Os estudos sobre as relações mútuas entre as pessoas e o ambiente buscam subsidiar melhorias no contexto urbano a partir de métodos e técnicas pautados na compreensão do uso de espaços públicos e privados. A crescente demanda pela promoção de ambientes amigáveis para idosos e crianças nos cenários urbanos direcionou esta pesquisa e elencou dois componentes: o panorama relativo à população local e o arcabouço teórico da psicologia ambiental. Para tanto, buscou-se identificar as principais atividades realizadas por crianças e idosos em seus respectivos locais de moradia. Foram avaliados os principais usos e atividades desses dois grupos, em duas vizinhanças, diferenciando-os de acordo com suas especificidades em termos de demandas individuais e ambientais. As observações sistemáticas a partir da técnica de mapeamento comportamental centrado no lugar (MCCL) ocorreram na cidade de Brasília, Distrito Federal (DF) e permitiram compreender o processo de apropriação dos espaços na infância e na velhice e suas repercussões em termos da congruência pessoa-ambiente. Cada um destes setores organizados a partir de elementos específicos direciona as ações dos participantes para determinados tipos de comportamentos, observados de maneira a compor um roteiro em que a brincadeira (lazer ativo) surge como central na infância e a caminhada (circulação) como mais potente para a população idosa. Os resultados demonstram que o diálogo entre a psicologia ambiental e a ciência do desenvolvimento humano tem sido bastante profícuo e tem contribuído para a compreensão de aspectos da relação pessoa-ambiente em diferentes momentos do ciclo de vida.(AU)

Studies on the mutual relations between people and the environment seek to support improvements in the urban context from methods and techniques based on understanding the use of public and private spaces. The growing demand for the promotion of friendly urban environments for older people and children guided this research, with two notable components: the panorama related to the local population and the theoretical framework of Environmental Psychology. Therefore, we sought to identify the main activities carried out by children and older people in their respective dwellings. The main uses and activities of these two groups were evaluated in two neighborhoods, differentiating them according to their specificities in terms of individual and environmental demands. Systematic observations using the place-centered behavioral mapping technique took place in the city of Brasília, Federal District, and allowed us to understand the process of appropriation of spaces in childhood and old age and its repercussions in terms of person-environment congruence. Each of these sectors, organized from specific elements, directs the participants' actions towards certain types of behavior, observed in order to compose a script in which playing (active leisure) emerges as central in childhood and walking (circulation) as more potent for the older people. The results demonstrated that the dialogue between environmental psychology and the science of human development has been very fruitful and has contributed to the understanding of aspects of the person-environment relationship at different times in the life cycle.(AU)

Los estudios sobre las relaciones mutuas entre las personas y el medio ambiente buscan aportar mejoras en el contexto urbano mediante métodos y técnicas basados en la comprensión del uso de los espacios públicos y privados. La creciente demanda de la promoción de ambientes amigables para las personas mayores y los niños en entornos urbanos guio esta investigación y enumeró dos componentes: el panorama relacionado con la población local y el marco teórico de la Psicología Ambiental. En este contexto, buscamos identificar las principales actividades que realizan los niños y las personas mayores en sus respectivas viviendas. Se evaluaron los principales usos y actividades de estos dos grupos en dos barrios, diferenciándolos según sus especificidades en cuanto a las demandas individuales y ambientales. Las observaciones sistemáticas utilizando la técnica de mapeo conductual centrado en el lugar (MCCL) ocurrieron en la ciudad de Brasília, Distrito Federal (Brasil) y nos permitieron comprender el proceso de apropiación de espacios en la infancia y la vejez y sus repercusiones en la congruencia persona-ambiente. Cada uno de estos sectores, organizados a partir de elementos específicos, orienta las acciones de los participantes hacia determinados comportamientos, observados para componer un guion en el que el juego (ocio activo) emerge como central en la infancia y el caminar (circulación) como el más potente para las personas mayores. Los resultados demuestran que el diálogo entre la Psicología Ambiental y la ciencia del desarrollo humano ha sido muy fructífero y ha contribuido a la comprensión de aspectos de la relación persona-entorno en diferentes momentos del ciclo de vida.(AU)

Occupational Radiation Protection Aspects of Alkaline Leach Uranium in Situ Recovery (ISR) Facilities in the United States.

In situ recovery or in situ leach (ISR/ISL) uranium facilities, also referred to in the past as "uranium solution mining" have operated since the late 1960s in the US and in recent years have accounted for over 70% of US production and, internationally, approximately half of worldwide uranium supplies. Note that throughout this paper, the uranium in situ recovery process, also known as in situ leach, will be abbreviated as "ISR." This paper presents a summary of the occupational radiation protection aspects of typical ISR processes being employed in the United States today that have traditionally used alkaline-based uranium recovery solutions known as lixiviants. The paper describes the health physics and associated monitoring programs necessary to adequately measure and control radiological doses to workers based on the radiological character of these processes. Although many radiological characteristics are similar to that of conventional mills, conventional-type tailings as such are not generated. However, liquid and solid by-product materials may be generated and impounded, which can result in sources of occupational exposure. Some special monitoring considerations are required due to the manner in which Rn gas is involved in the process. The major aspects of the health physics and radiation protection programs that have been developed at these facilities over many years are discussed and listed in the Conclusion section of the paper.

Hands-on Physics Education of Residents in Diagnostic Radiology.

RATIONALE AND OBJECTIVES: The American Board of Radiology Core Examination integrates assessment of physics knowledge into its overall testing of clinical radiology, with an emphasis on understanding image quality and artifacts, radiation dose, and patient safety for each modality or subspecialty organ system. Accordingly, achieving a holistic approach to physics education of radiology residents is a huge challenge. The traditional teaching of radiological physics-simply through didactic lectures-was not designed for such a holistic approach. Admittedly, time constraints and clinical demands can make incorporation of physics teaching into clinical practice problematic. We created and implemented a week-long, intensive physics rotation for fledgling radiology residents and evaluated its effectiveness. MATERIALS AND METHODS: The dedicated physics rotation is held for 1 week during the first month of radiology residency. It comprises three components: introductory lectures, hands-on practical clinical physics operations, and observation of clinical image production. A brief introduction of the physics pertinent to each modality is given at the beginning of each session. Hands-on experimental demonstrations are emphasized, receiving the greatest allotment of time. The residents perform experiments such as measuring radiation dose, studying the relationship between patient dose and clinical practice (eg, fluoroscopy technique), investigating the influence of acquisition parameters (kV, mAs) on radiographs, and evaluating image quality using computed tomography, magnetic resonance imaging, ultrasound, and gamma camera/single-photon emission computed tomography/positron emission tomography phantoms. Quantitative assessment of the effectiveness of the rotation is based on an examination that tests the residents' grasp of basic medical physics concepts along with written course evaluations provided by each resident. RESULTS: The pre- and post-rotation tests show that after the physics rotation, the average correct score of 25 questions improved from 13.6 ± 2.4 to 19 ± 1.2. The survey shows that the physics rotation during the first week of residency is favored by all residents and that 1 week's duration is appropriate. All residents are of the opinion that the intensive workshop would benefit them in upcoming clinical rotations. Residents acknowledge becoming more comfortable regarding the use of radiation and providing counsel regarding radiation during pregnancy. CONCLUSIONS: An immersive, short-duration, clinically oriented physics rotation is well received by new or less experienced radiology trainees, correlates basic physics concepts with their relevance to clinical imaging, and more closely parallels expectations of the American Board of Radiology Core Examination.

The role of the health physicist in nuclear security.

Health physics is a recognized safety function in the holistic context of the protection of workers, members of the public, and the environment against the hazardous effects of ionizing radiation, often generically designated as radiation protection. The role of the health physicist as protector dates back to the Manhattan Project. Nuclear security is the prevention and detection of, and response to, criminal or intentional unauthorized acts involving or directed at nuclear material, other radioactive material, associated facilities, or associated activities. Its importance has become more visible and pronounced in the post 9/11 environment, and it has a shared purpose with health physics in the context of protection of workers, members of the public, and the environment. However, the duties and responsibilities of the health physicist in the nuclear security domain are neither clearly defined nor recognized, while a fundamental understanding of nuclear phenomena in general, nuclear or other radioactive material specifically, and the potential hazards related to them is required for threat assessment, protection, and risk management. Furthermore, given the unique skills and attributes of professional health physicists, it is argued that the role of the health physicist should encompass all aspects of nuclear security, ranging from input in the development to implementation and execution of an efficient and effective nuclear security regime. As such, health physicists should transcend their current typical role as consultants in nuclear security issues and become fully integrated and recognized experts in the nuclear security domain and decision making process. Issues regarding the security clearances of health physics personnel and the possibility of insider threats must be addressed in the same manner as for other trusted individuals; however, the net gain from recognizing and integrating health physics expertise in all levels of a nuclear security regime far outweighs any negative aspects. In fact, it can be argued that health physics is essential in achieving an integrated approach toward nuclear safety, security, and safeguards.

Annual committed effective dose from olive oil (due to 238U, 232Th, and 222Rn) estimated for members of the Moroccan public from ingestion and skin application.

Olive oil is traditionally refined and widely consumed by Moroccan rural populations. Uranium (238U), thorium (232Th), radon (222Rn), and thoron (220Rn) contents were measured in various locally produced olive oil samples collected in rural areas of Morocco. These radionuclides were also measured inside various bottled virgin olive oils consumed by the Moroccan populations. CR-39 and LR-115 type II solid state nuclear track detectors (SSNTDs) were used. Annual committed effective doses due to 238U, 232Th, and 222Rn from the ingestion of olive oil by the members of the general public were determined. The maximum total committed effective dose due to 238U, 232Th, and 222Rn from the ingestion of olive oil by adult members of Moroccan rural populations was found equal to 5.9 µSv y-1. The influence of pollution due to building material dusts and phosphates on the radiation dose to workers from the ingestion of olive oil was investigated, and it was found that the maximum total committed effective dose due to 238U, 232Th, and 222Rn was on the order of 0.22 mSy y-1. Committed effective doses to skin due to 238U, 232Th, and 222Rn from the application of olive oil masks by rural women were evaluated. The maximum total committed effective dose to skin due to 238U, 232Th, and 222Rn was found equal to 0.07 mSy y-1 cm-2.

The history of radiation use in medicine.

INTRODUCTION: Radiation was discovered just slightly more than a century ago, with a profound effect on both industry and medicine. Several notable scientists were key in bringing radiation to the forefront. METHODS: Historical review of scientists who played key roles in the discovery of radiation and its use in medicine are reviewed. RESULTS: Wilhelm Roentgen, Henri Becquerel, and Marie and Pierre Curie's work is reviewed. The field of radiation safety was born to protect those handling radiation in addition to patients who received radiation for medical purposes. CONCLUSION: Radiation use in medicine continues to evolve after notable discoveries by Nobel Prize-winning scientists.

Evaluation of radiological versus chemical toxicity limits for varying enrichments of uranium for Department of Energy facilities.

On 8 June 2007, the Department of Energy amended its occupational radiation protection rule Title 10 Code of Federal Regulations Part 835, Occupational Radiation Protection. The Department of Energy revised the radiation weighting factors, tissue weighting factors, and most of the dosimetric terms used in Title 10 Code of Federal Regulations Part 835 to reflect the recommendations for assessing dose and associated terminology from ICRP Publication 60, 1990 Recommendations of the ICRP on Radiological Protection. In support of the amendment, the Department of Energy is revising its guidance documents on evaluation of radiological vs. chemical toxicity limits for varying enrichments of uranium. The revised guidance is based on the updated dosimetric models and provides a useful tool for evaluating when either radiological or chemical toxicity concerns are more limiting.

Spatial distribution of beta extremity doses in nuclear medicine: a feasibility study with thin alpha-Al2O3:C TLDs.

Exposures to the extremities have increased due to new therapeutic protocols involving beta sources. In this study, thermoluminescent dosimeters based on alpha-Al(2)O(3):C were used to map the dose distribution to the extremities of physicians and paramedical personnel handling beta emitters. The results showed a strong inhomogeneous dose distribution between different phalanxes, fingers and hands of all the investigated subjects, without an indication of systematic trends in the dose patterns. Consequently, conventional dosimetric practices, based on the use of wrist or ring dosimeters, may be not suitable for providing reliable assessments of the inhomogeneous doses received at the fingertip.

Molecular imaging and the unification of multilevel mechanisms and data in medical physics.

Molecular imaging (MI) constitutes a recently developed approach of imaging, where modalities and agents have been reinvented and used in novel combinations in order to expose and measure biologic processes occurring at molecular and cellular levels. It is an approach that bridges the gap between modalities acquiring data from high (e.g., computed tomography, magnetic resonance imaging, and positron-emitting isotopes) and low (e.g., PCR, microarrays) levels of a biological organization. While data integration methodologies will lead to improved diagnostic and prognostic performance, interdisciplinary collaboration, triggered by MI, will result in a better perception of the underlying biological mechanisms. Toward the development of a unifying theory describing these mechanisms, medical physicists can formulate new hypotheses, provide the physical constraints bounding them, and consequently design appropriate experiments. Their new scientific and working environment calls for interventions in their syllabi to educate scientists with enhanced capabilities for holistic views and synthesis.

Revisión del plan de estudio de la asignatura Física Médica: problemática existente en su adecuación dentro de la estructura curricular de la oncología / Review of the Medical Physics subject curriculum: current problems in its adjustment to the curricular structure of oncology

Se revisó el plan de estudio de la asignatura Física Médica en el proceso de formación de los especialistas en oncología, con vista a proponer los cambios indispensables en la problemática existente para lograr la adecuación de su contenido dentro de la estructura curricular de la cancerología(AU)

The curriculum of the Medical Physics subject in the training of oncology specialists was reviewed, with the view of proposing essential changes in the current problems to achieve the adjustment of its contents to the curricular structure of cancerology(AU)

Revisión del plan de estudio de la asignatura Física Médica: problemática existente en su adecuación dentro de la estructura curricular de la oncología / Review of the Medical Physics subject curriculum: current problems in its adjustment to the curricular structure of oncology

Se revisó el plan de estudio de la asignatura Física Médica en el proceso de formación de los especialistas en oncología, con vista a proponer los cambios indispensables en la problemática existente para lograr la adecuación de su contenido dentro de la estructura curricular de la cancerología.

The curriculum of the Medical Physics subject in the training of oncology specialists was reviewed, with the view of proposing essential changes in the current problems to achieve the adjustment of its contents to the curricular structure of cancerology.

New ICRP recommendations.

This paper provides a review of the 2007 recommendations of the International Commission on Radiological Protection (ICRP). These new recommendations take account of the latest biological and physical information and consolidate the additional guidance provided by ICRP since 1990. The changes to the scientific data are not substantial. ICRP has retained its fundamental hypothesis for the induction of stochastic effects of linearity of dose and effect without threshold and a dose and dose-rate effectiveness factor (DDREF) of 2 to derive nominal risk coefficients for low doses and low dose rates. While the overall detriment from low radiation doses has remained unchanged, ICRP has made adjustments to the values of the radiation and tissue weighting factors. In particular, the tissue weighting factor for breast has increased while that for gonads has decreased. There are some presentational changes to the system of protection. While ICRP has maintained the three fundamental principles--justification, optimisation of protection, and dose limitation-it has attempted to develop a more holistic approach to radiological protection covering all exposure situations--planned, existing and emergency--and all radiation sources, whether of natural or artificial origin. This approach should ensure that attention is focused on those exposures that can reasonably be controlled. It has also strengthened the principle of optimisation of protection with a particular emphasis on the use of constraints for planned exposure situations and reference levels for existing and emergency exposure situations. Dose constraints and reference levels are categorised into three bands which should assist in rationalising the many values of dose restrictions given in earlier ICRP publications. There are no changes to the dose limits. ICRP also indicates its intentions with respect to the development of further guidance on the protection of the environment. The fact that these new recommendations are more a matter of consolidation of previous ICRP recommendations and guidance should provide confidence that the system of protection established by and large in its present form several decades ago has reached a certain level of maturity. As such, no major changes to radiological protection regulations based on the 1990 recommendations should be necessary.

New recommendations from the International Commission on Radiological Protection--a review.

For almost half a century, the International Commission on Radiological Protection (ICRP) has revised its recommendations on radiological protection with an average frequency of about 10 years, building on the experience gained in their implementation. This has ensured that the recommendations remain up to date and fit for purpose and it is this that has led in turn to their wide acceptance internationally. Indeed, the 1990 version of the recommendations forms the basis of the international radiological protection standards and the systems of control of exposure to ionizing radiation in many countries throughout the world. This version introduced new concepts and a more holistic approach to radiological protection but marrying the different exposure situations into one coherent framework has proved not to be straightforward and further reflection seemed necessary in order to satisfy both those who are responsible for the development of the control systems as well as a broader audience. Review of the 1990 recommendations started around 1998 and, since then, many ideas have been explored and avenues followed. Eventually, new recommendations were agreed by the Commission at its meeting in Essen in March 2007. This paper provides a review of these new recommendations and their possible implications.

Hyperthermia, a modality in the wings.

Hyperthermia is a heat-treatment. It is widely used in various medical fields and has a well-recognized effect in oncology. Its effect is achieved by overheating of the targeted tissues. It is an ancient treatment and a promising physical approach with lack of acceptance by the serious medical use. To accept the method we need strong proofs and stable, reproducible treatment quality, but we are limited by biological, physical/technical and physiological problems. However, the main point--I believe--is the incorrect characterization and unrealistic expectations from this capable method. The temperature concept of the quality assurance guidelines has to be replaced by the heat-dose sensitive characterization, pointing the essence of the hyperthermia method.

The contribution of medical physics to the development of psoralen photochemotherapy (PUVA) in the UK: a personal reminiscence.

Psoralen photochemotherapy (PUVA) is the combined treatment of skin disorders with a photosensitizing drug (Psoralen) and UltraViolet A radiation. The introduction of PUVA therapy has arguably been the most important development in dermatology over the past 30 years and from the first days of the treatment being introduced in the UK, British medical physicists were an integral part of the effort to establish it. Medical physicists have contributed to this development in a number of ways, from designing irradiation units in the early days of the technique, through to collaborating with dermatologists in prosecuting clinical and experimental studies aimed at improving patient outcomes. That the dose of UVA radiation is administered quantitatively, and not qualitatively, has probably been the single most important contribution made by several medical physicists over this period. However, despite concerns that were expressed almost 30 years ago about the accuracy with which UVA doses are administered to patients, the medical physics community still has some way to go before we can be satisfied that statements about UVA irradiance and dose can be made with confidence.

Radionuclides in the terrestrial ecosystem near a Canadian uranium mill--Part I: Distribution and doses.

Soils, vegetation, small mammals, and birds were measured for uranium series radionuclides at three sites near the operating Key Lake uranium mill in northern Saskatchewan. Sites, impacted by windblown tailings and mill dust, had significantly higher concentrations of uranium, 226Ra, 210Pb, and 210Po in soils, litter, vegetation, tree needles and twigs, small mammals, and birds, compared to a control site. Samples were collected from both upland jackpine and black spruce bog habitats in triplicate at each site. Both habitats were similar in radionuclide accumulation. Absorbed doses averaged 0.92, 8.4, and 4.9 mGy y(-1) to small mammals and 2.0, 5.8, and 2.8 mGy y(-1) to Lincoln's sparrows at the control, tailings, and mill sites, respectively. These doses do not include doses from short-lived radon progeny. The majority of the dose increment at the tailings and mill sites was due to 226Ra, whereas it was 210Po at the control site. Thus, use of a radiation weighting factor of 20 for alpha radiation raised equivalent doses (in mSv y(-1)) by nearly a factor of 20.