Batteryless NFC dosimeter tag for ionizing radiation based on commercial MOSFET

This paper reports the development, evaluation and validation of DosiTag, a dosimetric platform based on Near Field Communication (NFC) technology. The designed system comprises two main parts: a passive NFC sensing tag as the dosimeter unit, which includes a commercial P-channel MOSFET transistor as radiation sensor; and an NFC-enabled smartphone running a custom-developed application as the reader unit. Additionally, a cloud service based on the messaging protocol Message Queue Telemetry Transport (MQTT) has been implemented using a broker/client architecture to allow the storage and classification of the patient’s data. The dosimeter tag was designed using commercial low-power integrated circuits (ICs) and it can operate without any external power supply or battery, being supplied by the smartphone through the radio frequency (RF) energy harvested from the NFC link. The radiation dose is measured through the increase of the DMOS transistor source voltage using the smartphone as the reader unit. Two tag prototypes have been characterized with a 6 MV photon beam and radiation doses up to 57 Gy and 42 Gy, respectively. The achieved average sensitivity is (4.37 ± 0.04) mV/ Gy with a resolution of 2 cGy, which goes beyond the state-of-the-art of previous NFC dosimeters and places DosiTag as a low-cost promising electronic platform for dose control in radiotherapy treatments.Junta de Andalucía (Spain), projects numbers PI-0505–2017 FEDER/Junta de Andalucía- Consejería de Economía y Conocimiento Project B-TIC-468-UGR18Proyecto del Plan Nacional I + D: PID2019–104888GB-I00 and Proyectos I + D + i Junta de Andalucía 2018: P18-RT-3237H2020 ELICSIR project (grant No. 857558)Grant IJC2020-043307-I funded by MCIN/AEI/ 10.13039/501100011033European Union NextGenerationEU/ PRT

A radiobiological study of the schemes with a low number of fractions in high-dose-rate brachytherapy as monotherapy for prostate cancer

Purpose Schemes with high doses per fraction and small number of fractions are commonly used in high-dose-rate brachytherapy (HDR-BT) for prostate cancer. Our aim was to analyze the differences between published clinical results and the predictions of radiobiological models for absorbed dose required in a single fraction monotherapy HDR-BT. Material and methods Published HDR-BT clinical results for low- and intermediate-risk patients with prostate cancer were revised. For 13 clinical studies with 16 fractionation schedules between 1 and 9 fractions, a dose-response relation in terms of the biochemical control probability (BC) was established using Monte Carlo-based statistical methods. Results We obtained a value of α/β = 22.8 Gy (15.1-60.2 Gy) (95% CI) much larger than the values in the range 1.5-3.0 Gy that are usually considered to compare the results of different fractionation schemes in prostate cancer radiotherapy using doses per fraction below 6 Gy. The doses in a single fraction producing BC = 90% and 95% were 22.3 Gy (21.5-24.2 Gy) and 24.3 Gy (23.0-27.9 Gy), respectively. Conclusions The α/β obtained in our analysis of 22.8 Gy for a range of dose per fraction between 6 and 20.5 Gy was much greater than the one currently estimated for prostate cancer using low doses per fraction. This high value of α/β explains reasonably well the data available in the region of high doses per fraction considered.Spanish Ministerio de Ciencia y Competitividad FPA2015-67694-PEuropean Union (EU)Junta de Andalucía FQM038

Variabilidad en radiobiología

Tesis Univ. Granada. Departamento de Física Atómica, Molecular y Nuclear. Departamento de Radiología y Medicina Física. Leída el 15 de junio de 201

Data from: Vitellogenin-like A–associated shifts in social cue responsiveness regulate behavioral task specialization in an ant

Division of labor and task specialization explain the success of human and insect societies. Social insect colonies are characterized by division of labor with workers specializing on brood care early and foraging later in life. Theory posits that this task switching requires shifts in responsiveness to task-related cues, yet experimental evidence is weak. Here we show that a Vitellogenin (Vg) ortholog identified in a RNAseq study on the ant Temnothorax longispinosus is involved in this process: Using phylogenetic analyses of Vg and Vg-like genes, we firstly show that this candidate gene does not cluster with the intensively studied honey bee Vg, but falls into a separate Vg-like A cluster. Secondly, an experimental knockdown of Vg-like A in the fat body caused a reduction in brood care and an increase in nestmate care in young ant workers. Nestmate care is normally exhibited by older workers. We demonstrate experimentally that this task switch is at least partly based on Vg-like-A-associated shifts in responsiveness from brood to worker cues. We thus reveal a novel mechanism leading to early behavioral maturation via changes in social cue responsiveness mediated by Vg-like A and associated pathways, which proximately play a role in regulating division of labor