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FANT (Fuente Ampliada de Neutrones Térmicos; in Spanish) is a thermal neutron irradiation facility with an extended and very uniform irradiation area, which has been developed by the Neutron Measurement Laboratory of the Energy Engineering Department at Universidad Politécnica de Madrid (LMN-UPM). In FANT, an isotopic neutron source ( 241 Am/ 9 Be) produces the primary neutrons. The design and facility optimization were carried out by extensive Monte Carlo calculations. In addition, Monte Carlo methods were used to evaluate the facility's performance to produce a constant and uniform thermal neutron field; these results were validated through experimental methods. FANT is designed to have two neutron sources; the objective of this work is to estimate the ambient dose equivalent due to neutrons and gamma-rays by Monte Carlo methods, and to compare these values with measured experimental doses. Thus, the performance of FANT with the two 241 Am/ 9 Be sources of LMN-UPM, with regard to the ambient dose equivalent H*(10) produced by both neutrons and photons around the facility, is analyzed in this work. The results are compared with those previously obtained in the framework of the results obtained with the LB6411 device around FANT., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Objective: To determine 5-year survival in patients with colorectal cancer (CRC) according to patient and tumor characteristics., Methods: Longitudinal study based on incident cases of invasive CRC between 2008 and 2017 captured by the Manizales Population-based Cancer Registry (n=850). Patients were followed up to August 24th, 2021. Cause-specific survival and net survival were calculated for sociodemographic and tumor characteristics, and Cox multivariate was fitted., Results: Fifty-five percent of cases occurred in women. The most frequent histological type was adenocarcinoma (78.2%). The most frequent locations were rectum (32.0%), ascending colon (16.6%), and sigmoid (16.2%). Twenty-five percent of cases were diagnosed in stage IV. There were 567 deaths due to CRC. The 5-year specific survival was 45.8% (95%CI 42.4-49.3), with independent effects for age (HR=1.83; 95%CI 1.26-2.65 age >75 years vs. <50 years) and advanced clinical stage (HR=2.5 and HR 5.7 for stages III and IV vs. stage I, respectively). Lower survival was observed in patients of medium socioeconomic status compared with higher socioeconomic status (HR=1.52; 95%CI 1.08-2.14), but not in patients of low socioeconomic status. No independent effects were observed for the health insurance regime., Conclusions: In Manizales, approximately 5 out of 10 patients with invasive CRC die in the first five years after diagnosis, with a lower survival in patients older than 75 years, from medium socioeconomic level and diagnosed in advanced clinical stages.

The thermal neutron irradiation device (FANT), developed at the Neutron Measurements Laboratory of the Energy Engineering Department at Universidad Politécnica de Madrid, is a high-density polyethylene regular parallelepiped, with a rather uniform neutron fluence inside its irradiation chamber. It uses a Am95241/Be49 neutron source aiming to provide thermal neutron fluence rates. Neutron spectra and neutron fluences were estimated with Monte Carlo methods in the FANT irradiation chamber when a Cf98252 neutron source is used and were compared with the results obtained with the Am95241/Be49 source. Regardless of the neutron source, the largest contribution is due to thermal neutrons, producing also epithermal and fast neutrons. Per neutron emitted by the source, the use of Cf98252 produces a larger amount of neutrons., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Proton therapy is an external radiotherapy using proton beams with energies between 70 and 230 MeV to treat some type of tumours with outstanding benefits, due to its energy transfer plot. There is a growing demand of facilities taking up small spaces and Compact Proton Therapy Centers (CPTC), with one or two treatment rooms, supposing the technical response of manufacturers to this request. A large amount of stray radiation is yielded in the interaction of proton beam used in therapy, neutrons mainly, hence, optimal design of shielding and verifications must be carried out in commissioning phases. Currently, almost 50 proton centers are under construction and start up in several countries, including ten in Spain. In the present work the effectiveness of shielding in two CPTC was verified with the Monte Carlo code MCNP6 by calculating the ambient dose equivalent, H*(10) due to secondary neutrons, outside the enclosures and walls of the center. The facilities modelled were the two centers currently operating in Spain, the first, since December 2019, with a superconductor synchrocyclotron, and the second, since March 2020, with a compact synchrotron. The geometry and materials are based on dimensions proposed a priori by the vendors, therefore, the paper is focused on check the suitability of the materials and thickness of the walls of the centers. Several models of the radiation sources were simulated, starting from a conservative assumptions, followed by more realistic scenarios. In all cases, the results reached for the ambient dose equivalent, H*(10), were below 1 mSv/year, which is the legal limit considered for the public in international references. Finally, considering that the recent ICRU Report 95 proposes changes in the operational quantities, the dose outside shieldingt has been evaluated in terms of the new next area surveillance quantity, H*, known as ambient dose, in the process of implementation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Neutron area monitors do not often have a good adjustment of their dose response functions to the ICRP74 neutron fluence-to-H*(10) conversion function between 10 and 20 MeV. The objective of this work is to establish a methodology to combine the dose response functions of Berthold LB6411 and WENDI-II, adjusting this combined function to the ICRP74 conversion function: this combination shows an almost perfect adjustment between 0.5 and 20 MeV. Thus, this article presents an easy and cheap alternative to the recalibration in D-T generators., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Atomic and radiological crises can be caused by accidents, military activities, terrorist assaults involving atomic installations, the explosion of nuclear devices, or the utilization of concealed radiation exposure devices. Direct damage is caused when radiation interacts directly with cellular components. Indirect effects are mainly caused by the generation of reactive oxygen species due to radiolysis of water molecules. Acute and persistent oxidative stress associates to radiation-induced biological damages. Biological impacts of atomic radiation exposure can be deterministic (in a period range a posteriori of the event and because of destructive tissue/organ harm) or stochastic (irregular, for example cell mutation related pathologies and heritable infections). Potential countermeasures according to a specific scenario require considering basic issues, e.g., the type of radiation, people directly affected and first responders, range of doses received and whether the exposure or contamination has affected the total body or is partial. This review focuses on available medical countermeasures (radioprotectors, radiomitigators, radionuclide scavengers), biodosimetry (biological and biophysical techniques that can be quantitatively correlated with the magnitude of the radiation dose received), and strategies to implement the response to an accidental radiation exposure. In the case of large-scale atomic or radiological events, the most ideal choice for triage, dose assessment and victim classification, is the utilization of global biodosimetry networks, in combination with the automation of strategies based on modular platforms.

A study was conducted to describe the cases of thyroid cancer in Manizales, Colombia. This study describes the characteristics of patients; and tumors according to size, laterality, focalization, nodal involvement, contiguous invasion, metastasis and TNM staging. A total of 672 cases were analyzed, 84.8% of which were women between 40 and 64 years of age. From the population, 34.1% were cases diagnosed in early stages and 15% of the tumors were >20 mm in size. Nodal and adjacent tissue involvement was present in 33% and 3% of the cases, respectively. Distant metastasis was documented in 1% of the cases. Papillary carcinoma was present in 82% of cases. Thyroid cancer in Manizales is more frequent in adult women. Tumor size and being at the early stages are factors that suggest improvement in early detection.

Neutron techniques to characterize materials have a wide range of applications, one of the major developments being the identification of terrorist threats with chemical, biological, radiological, nuclear and explosives (CBRNE) materials. In this work, a thermal neutron irradiation system, using a 241 Am/ 9 Be source of 111 GBq inside polyethylene cylindrical moderators, has been designed, built and tested. The geometry of moderator and the neutron source position were fixed trying to maximize the thermal neutrons flux emitted from the system. Therefore, the system is in fact a thermalized neutron source taking advantage of the backscattered neutrons, achieving thermal fluence rates of up to 5.3x10 2  cm -2  s -1 , with dominantly thermal spectra. Samples can be placed there for several hours and thereafter be measured to identify their component elements by NAA (Neutron Activation Analysis). Through Monte Carlo techniques employing the MCNP6 code (Pelowitz et al., 2014), four different configurations with polyethylene cylinders were simulated to choose the most adequate geometry. The theoretical model was then replicated in the neutronics hall of the Neutron Measurements Laboratory of the Energy Engineering Department of Universidad Politécnica de Madrid (LMN-UPM), carrying out experimental measurements using a BF 3 neutron detector. A high agreement between MCNP6 results and the experimental values measured was observed. Consequently, the system developed could be employed in future laboratory experiments, both for the identification of trace substances by NAA and for the calibration of neutron detection equipment., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

A thermal neutron system intended to be used in neutron activation analysis has been designed by Monte Carlo methods. The device is based on a 241 Am/ 9 Be neutron source of 111 GBq, placed inside a cylindrical cavity open inside a parallelepiped of moderator material. Three different moderator materials, water, graphite and high-density polyethylene (HDPE), were simulated to check what is the most suitable for the detection system, concluding that HDPE reach the better performance. The device achieves an increased thermal neutron flux by taking advantage of neutron moderation in the polyethylene and the neutron scattering in the irradiation chamber walls. The thermal fluence rates obtained were 904 cm -2   s -1 , i.e. 8.144 cm -2  s -1 GBq -1 , with a fraction of thermal neutrons at the best point of 83% of pristine fast neutrons emitted by the source. The device has been designed by Monte Carlo techniques using the MCNP6 code, and the main tasks developed were to select the moderator material and to maximize the thermal neutrons flux in the irradiation chamber., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

During the International Conference on Radiation Protection in Medicine held in Bonn in 2012, several areas for improvement were identified, including specific actions related with justification, optimization, role of manufacturers, radiation protection education and training, strategic research, data collection on medical and occupational exposures, prevention of incidents and accidents, radiation safety culture, risk-benefit dialogue and implementation of the radiation safety standards. The outcomes of the Bonn Conference were summarized in the so-called 'Bonn Call for Action', identifying 10 priority actions to enhance RP in medicine. Trying to analyse the progress in the implementation of this 'Call for Action' in the Ibero-American region, several international organizations organized the 'Ibero-American Conference on Radiation Protection in Medicine' (Conferencia Iberoamericana sobre Protección Radiológica en Medicina, CIPRaM) held in Madrid, in October 2016. CIPRaM was structured in eight thematic sessions dealing with: diagnostic and dental radiology, image guided interventional radiology, nuclear medicine, radiation therapy, health authorities and radiation protection regulators, professional associations of technologists and nurses, professional associations of medical physicists and radiation protection experts, and universities and researchers in radiation protection in medicine. This paper summarizes the main results of that Conference based on the consensus achieved about main problems, solutions, and indicators to evaluate the implementation of the proposed solutions.

The response of a scintillation neutron detector of ZnS(Ag) with 10 B was calculated, using the MCNPX Monte Carlo Code. The detector consists of four panels of polymethyl methacrylate (PMMA) and five thin layers of ~0.017cm thick 10 B+ZnS(Ag) in contact with the PMMA. The response was calculated for the bare detector and with different thicknesses of High Density Polyethylene, HDPE, moderator for 29 monoenergetic sources as well as 241 AmBe and 252 Cf neutrons sources. In these calculations the reaction rate 10 B(n, α) 7 Li and the neutron fluence in the sensitive area of the detector 10 B+ZnS(Ag) was estimated. Measurements were made at the Neutron Measurements Laboratory, Universidad Politécnica de Madrid, LMN-UPM, to quantify the detections in counts per second in response to a 252 Cf neutron source separated 200cm. The MCNPX computations were compared with measurements to estimate the efficiency of ZnS(Ag) for detecting the α that is created in the 10 B(n, α) 7 Li reaction. After validating new models with different geometries it will be possible to improve the detector response trying to achieve a sensitivity of 2.5cps-ng 252 Cf comparable with the response requirements for 3 He detectors installed in the Radiation Portal Monitors, RPMs. This type of detector can be considered an alternative to the 3 He detectors for detection of Special Nuclear Material, SNM., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Background and Objectives: Screening colonoscopy with polipectomy reduces colonorectal cancer incidence and mortality. An adequate bowel cleansing is one of the keys to achieving best results with this technique. Oral sodium phosphate solution (OSP) had a widespread use in the 90s decade. Its efficacy was similar to polyethylene glycol (PEG) solution, but with less cost and convenient administration. Series of patients with acute renal failure due to OSP use have been reported. However, large cohorts of patients found no difference in the incidence of renal damage between these two solutions., Methods: From 2006 to 2009 we identified twelve cases of phosphate nephropathy after colonoscopy prepared with OSP. All patients were followed up to six months. All patients had received just a single dose., Results: We analyzed 12 cases with phosphate nephropathy; three patients debuted with AKI and nine patients had chronic renal injury. Four cases were confirmed with renal biopsy. One patient with AKI needed hemodialysis at diagnosis without subsequent recovery. Two patients (both with chronic damage) fully recovered their previous renal function. The remaining patients (nine) had an average loss of estimated glomerular filtration rate of 24ml/min/1.73m(2)., Conclusions: The use of OSP can lead to both acute and chronic renal damage. However, chronic injury was the most common pattern. Both forms of presentation imply a significant and irreversible loss of renal function. Further studies analyzing renal damage secondary to bowel cleaning should consider these two different patterns of injury., (Copyright © 2016 Sociedad Española de Nefrología. Published by Elsevier España, S.L.U. All rights reserved.)

When linacs operate above 8MV an undesirable neutron field is produced whose spectrum has three main components: the direct spectrum due to those neutrons leaking out from the linac head, the scattered spectrum due to neutrons produced in the head that collides with the nuclei in the head losing energy and the third spectrum due to room-return effect. The third category of spectrum has mainly epithermal and thermal neutrons being constant at any location in the treatment hall. These neutrons induce activation in the linac components, the concrete walls and in the patient body. Here the induced radioisotopes have been identified in concrete samples located in the hall and in one of the wedges. The identification has been carried out using a gamma-ray spectrometer., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

The neutronics hall of the Nuclear Engineering Department at the Polytechnical University of Madrid has been characterized. The neutron spectra and the ambient dose equivalent produced by an (241)AmBe source were measured at various source-to-detector distances on the new bench. Using Monte Carlo methods a detailed model of the neutronics hall was designed, and neutron spectra and the ambient dose equivalent were calculated at the same locations where measurements were carried out. A good agreement between measured and calculated values was found., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Phytopathogenicity was assessed of 55 isolates of Pythium spp. from the irrigation water of the district of the Poniente Almeriense (Almería, south-eastern Spain). The isolates were 16 of Pythium catenulatum, two of Pythium diclinum, two of Pythium paroecandrum and 35 of asexual forms with filamentous sporanges. Each Pythium isolate was tested with three types of damping-off phytopathogenicity tests with cucumber var. Ashley, in pots at 25 degrees C, varying the inoculation time (pre-seeding, pre-emergence and post-emergence). 83.64% of the isolates were found to be phytopathogenic. Phytopathogenic isolates were detected in all of the identified species. Mortality rates (%) decreased with the delay in inoculation time after the seeding. The isolates showing most growth in vitro were the most phytopathogenic.

Population density (number of propagules/l) of Pythium in the irrigation water has been studied in the reservoirs of the Poniente Almeriense (Almería, Spain). These reservoirs are habitually used in the watering of the greenhouse crops of the district. From October 1994 to August 1997, 17 sampling campaigns were carried out, 23 reservoirs were visited and three of them were sampled during three years. 300 ml of superficial water were sampled and analyzed in the laboratory by means of filtration with paper Whatman number 1, placed on Ponchet selective medium and incubated at 20 degrees C. Data of the physical-chemical characteristics of the water (temperature, pH, CE, anions and cations) were taken. The geographical and seasonal distributions of the population were correlated with the analyzed characteristics. The more frequent densities were among 0-100 propagules/l. A population's seasonality was observed, with a maximum in winter and a minimum in summer. When Cl- concentration was higher, the number of propagules/l was smaller.