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Preclinical studies represent an important step towards a deep understanding of the biological response to ionizing radiations. The effectiveness of proton therapy is higher than photons and, for clinical purposes, a fixed value of 1.1 is used for the relative biological effectiveness (RBE) of protons considered 1.1. Recent in vitro studies have reported that the RBE along the spread-out Bragg peak (SOBP) is not constant and, in particular, the RBE value increases on the distal part of SOBP. The present work has been carried-out in the perspective of a preclinical hadrontherapy facility at LNS-INFN and was focused on the experimental preparation of an in vivo study concerning the RBE variation along the SOBP. The main purpose of this work was to determine, using GEANT4-based Monte Carlo simulations, the best configuration for small animal treatments. The developed GEANT4 application simulates the proton-therapy beam line of LNS-INFN (CATANA facility) and allows to import the DICOM-CT images as targets. The RBE will be evaluated using a deterministic radiation damage like myelopathy as end-point. In fact, the dose at which the 50% of animals will show the myelopathy is supposed to be LET-dependent. In this work, we studied different treatment configurations in order to choose the best two that maximize the LET difference reducing as much as possible the dose released to healthy tissue. The results will be useful to plan hadrontherapy treatments for preclinical in vivo studies and, in particular, for the future in vivo RBE studies.

Considerable research has been conducted analyzing how demographic characteristics influence the public’s attitudes toward wildlife; however, less research of this type has been conducted in locations having long-standing species conservation efforts. Questionnaires were completed by residents living adjacent to such a location, the Archie Carr National Wildlife Refuge (ACNWR), to investigate which demographics explained residents’ knowledge of, attitudes toward, willingness to act for, and participation in sea turtle conservation. Residents who had a non-governmental organization (NGO) or government agency as their sea turtle information source had stronger positive attitudes toward sea turtles. Residents who possessed strong positive attitudes were more willing to engage in pro–sea turtle conservation behaviors. Overall, this research demonstrated that ACNWR residents’ source of sea turtle information being an NGO or government agency played a significant role in increasing residents’ knowledge ...

A worldwide radionuclide network of 80 stations, including 40 with noble-gas-detection capability forming part of the International Monitoring System, has been designed to monitor compliance with the Comprehensive Nuclear-Test-Ban Treaty. Pending entry into force of the Treaty, the certified stations are operating provisionally and so far an experience of over 100 station-years has been acquired for particulate stations. Noble gas systems are still under testing, though the operational experience is fast growing. A maintenance strategy is being developed on the basis of the experience acquired so far and the analysis of equipment failure.

Objective: This study was undertaken to assess the prevalence of obsessive-compulsive symptoms in a population of Italian adolescents. Method: A sample of 2877 high-school students, 1463 males (51%) and 1414 females (49%), aged 16–21 years were assessed with the Leyton Obsessional Inventory — Child Version (LOI-CV). Two groups of subjects were defined as ‘positive’ on the screen: the high interference (HI) (i.e. all subjects who scored 25 or more in the interference score), and the supernormals (Sn). Results: Females scored higher than males both on yes and interference scores. One hundred and nineteen (4.1%) and 87 (3.0%) constitute, respectively, the HI and the Sn groups. The most interfering symptoms were obsessions linked to dirt phobia, rumination and nail biting. Conclusion: The prevalence estimates of OCD symptoms confirmed the recent data of the literature that adolescent OCD symptoms are more frequent than was believed previously. Females showed more symptoms and more interference on personal functioning than males.

Int. J. Radiat. Oncol. Biol. Phys. 57 (2003) 732-738

PURPOSE: At the high dose-per-pulse rates used by some intraoperative radiotherapy (IORT) units, the employment of ionization chambers for dose measurements needs an appropriate correction (k(sat)) for ion recombination. Through a revision of the existing literature, the authors compared different methods for the determination of the recombination correction factor and their impact on clinical dosimetry. METHODS: A dosimetric characterization of IORT electron beams from a Linac Hitesys Novac7 (Aprilia-Latina, Italy) was performed. Dose-to-water (D(w)) values were measured with dose-per-pulse independent chemical dosimeters (operated by the Italian Primary Standard Dosimetry Laboratory, ENEA) and compared to doses obtained by two different parallel-plate ionization chamber models (Markus and Advanced Markus, PTW, Freiburg, Germany). For dose measurements using ionization chambers, the authors applied two different methods for the determination of the ion recombination correction factor (k(sat)), as suggested in previous articles. The first method is based on the experimental estimation of the free-electron fraction values p; the second one is based on the "nonstandard" two-voltage analysis including the free-electron component. RESULTS: For a Markus type chamber, there is a good agreement between the results on k(sat) and those reported in the literature for both methods, while for the Advanced Markus chamber, no data are available for comparison. CONCLUSIONS: Comparing values of D(w) obtained by dose-per-pulse independent dosimeters and by ionization chambers measurements corrected using the two different approaches, the authors can conclude that the k(sat) factor determination is very critical and that only an experimental protocol using ionization chamber intercalibration can be considered reliable.

Epithelioid leiomyosarcoma (EL) is a rare malignant tumor of mesenchymal origin. The Authors review the literature and report a case of gingival epithelioid leiomyosarcoma in a 40-year-old patient. In this case the leiomyosarcoma was located in the lower front dental group and invaded the symphysis menti. A segmentary mandibolectomy was performed with reconstruction using a non-revascularized autologous iliac bone graft. The differential diagnosis of primary EL is quite complex and it is grouped with other sarcomas, sarcomatoid carcinoma, myoepithelioma, amelanotic melanoma and metastases from gastrointestinal EL. Anatomopathological examination and immunohistochemical study enabled a definitive diagnosis of primary EL of gingiva. The follow-up calls for clinical-radiological check-ups every three months for the first year and every six months thereafter. One year after surgery there were no signs of recurrence.

Inverse planning and intensity modulated (IM) X-ray beam treatment techniques can achieve significant improvements in dose distributions comparable to those obtained with forward planned proton beams. However, intensity modulation can also be applied to proton beams and further optimization in dose distribution can reasonably be expected. A comparative planning exercise between IM X-rays and IM proton beams was carried out on two different tumor cases: a pediatric rhabdomyosarcoma and a prostate cancer. Both IM X-rays and IM protons achieved equally homogenous coverage of the target volume in the two tumor sites. Predicted NTCPs were equally low for both treatment techniques. Nevertheless, a reduced low-to-medium dose to the organs at risk and a lesser integral non-target mean dose for IM protons in the two cases favored the use of IM proton beams.

This study was undertaken to assess the prevalence of obsessive-compulsive symptoms in a population of Italian adolescents.A sample of 2877 high-school students, 1463 males (51%) and 1414 females (49%), aged 16-21 years were assessed with the Leyton Obsessional Inventory--Child Version (LOI-CV). Two groups of subjects were defined as 'positive' on the screen: the high interference (HI) (i.e. all subjects who scored 25 or more in the interference score), and the supernormals (Sn).Females scored higher than males both on yes and interference scores. One hundred and nineteen (4.1%) and 87 (3.0%) constitute, respectively, the HI and the Sn groups. The most interfering symptoms were obsessions linked to dirt phobia, rumination and nail biting.The prevalence estimates of OCD symptoms confirmed the recent data of the literature that adolescent OCD symptoms are more frequent than was believed previously. Females showed more symptoms and more interference on personal functioning than males.

Ball lie on a golf course fairway can impact a golfer's ability to control a shot. At present, there is no quantitative method to accurately measure golf ball lie (the amount of the ball exposed above the turfgrass canopy) on short-cut fairway turf. The objective of this work was to develop an instrument capable of accurately and quantitatively measuring golf ball lie on short-cut (1.27 cm) fairway turf. In previous work, a device (Lie-N-Eye) that measured golf ball lie on high-cut fairway turf (1.6-2.5 cm) was developed and tested on 25 Kentucky bluegrass (Poa pratensis L.) cultivars. That device lacked the sensitivity required to make measurements on short-cut turf. An improved device (Lie-N-Eye II) was developed to measure golf ball lie on short-cut (1.27 cm) bentgrass (Agrostis spp.) fairway turfgrasses. In October 2000, Lie-N-Eye II was tested on three creeping bentgrass [Agrostis stolonifera var. palustris (Huds.) Farw.] and three colonial bentgrass (A. capillaris L.) cultivars and adequately measured ball lie differences among bentgrass cultivars and species. Ball lies ranged from 38.7 mm to 40.7 mm of the ball exposed above the canopy (90.7 to 95.4% of the golf ball). Power curves generated from 18 measurements on each of six bentgrass cultivars indicate Lie-N-Eye II was able to detect a 1.65-mm difference between ball lies with a probability of approximately 90%.

Dans ce travail, on a etudie l'influence du cepage, du porte-greffe, du mode de conduite et de l'annee, sur les attaques de pourriture grise. II a ete constate que les cepages consideres presentent un comportement different; les cepages les plus sensibles sont, dans l'ordre, Carignan et Bovale, suivis par Monica et Nuragus, alors qu'Ugni-Blanc s'est revele plus resistant. Parmi les porte-greffe examines, 1103 Paulsen et 140 Ruggeri sont sujets aux attaques les plus importantes, tandis que le 420 A ou le 779 Paulsen se sont reveles moins sensibles. Les modes de conduite peuvent creer des conditions microclimatiques favorables aux attaques de Botrytis cinerea. Parmi les modes de conduite examines, le « tendone » et le « cordon » sont vulnerables, alors que le systeme « Guyot » permet de limiter les attaques. Ces essais montrent egalement les differences existant dans le degre des attaques de pourriture grise selon les annees.

Estimated age-adjusted incidence rates for cancer during 1971--77 among Kaiser Foundation Health Plan (KFHP) members living in a portion of the San Francisco Bay area (SFBA) characterized by a heavy concentration of petroleum and chemical industries were compared to estimated rates among KFHP members in the remainder of the SFBA. One hundred fifty-four comparisons were done for 41 selected cancer sites. The number of significant differences did not appear inconsistent with what might be expected by chance alone; furthermore, in most of these instances the so-called exposed area showed the lower rate. These findings provided some assurance that place of residence near petrochemical industries is not associated with increased cancer risk.

Estimated age-adjusted incidence rates for cancer during 1971--77 among Kaiser Foundation Health Plan (KFHP) members living in a portion of the San Francisco Bay area (SFBA) characterized by a heavy concentration of petroleum and chemical industries were compared to estimated rates among KFHP members in the remainder of the SFBA. One hundred fifty-four comparisons were done for 41 selected cancer sites. The number of significant differences did not appear inconsistent with what might be expected by chance alone; furthermore, in most of these instances the so-called exposed area showed the lower rate. These findings provided some assurance that place of residence near petrochemical industries is not associated with increased cancer risk.