Radiation Units Research Articles

Short-Term Photovoltaic Power Generation Prediction Model Based on Improved Data Decomposition and Time Convolution Network

In response to the volatility of photovoltaic power generation, this paper proposes a short-term photovoltaic power generation prediction model (HWOA-MVMD-TPA-TCN) based on a Hybrid Whale Optimization Algorithm (HWOA), multivariate variational mode decomposition (MVMD), temporal pattern attention mechanism (TPA), and temporal convolutional network (TCN). In order to improve the accuracy of photovoltaic power generation forecasting, HWOA-MVMD is used for data decomposition, the Minimum Mode Overlap Component (MMOC) is used as the objective function, the photovoltaic power generation sequence is decomposed into finite Intrinsic Mode Functions (IMFs) according to the optimal solution, and the training set is formed with key meteorological variable data such as total radiation (unit: W/m2), ambient temperature, and humidity. Then, the TPA-TCN model is used to train the sub-sequences, the final predicted values are obtained after superimposing the reconstruction of the prediction results, and finally the prediction error of the photovoltaic power generation data is studied. The proposed method is applied to real photovoltaic power generation data from a commercial center in Tianjin and is compared with HWOA-MVMD-BiLSTM, GWO-MVMD-TPA-TCN, and TPA-TCN prediction models. The simulation results demonstrate that the MAE value of the forecast method proposed in this paper is 1.95 MW and the RMSE value is 2.55 MW, which can be reduced by up to 33.74% and 38.85%, respectively. The HWOA-MVMD-TPA-TCN-based short-term photovoltaic power generation prediction model presented in this paper achieves higher prediction accuracy and superior performance, serving as a valuable reference for related research.

A Multipolarized Traveling-Wave Series-Fed Antenna Array Based on Patch

In this paper, a simple broadband multipolarized traveling-wave series-fed antenna array is proposed. The radiation unit cells are multiple squares. The square unit cell will change between circular polarized (CP) and linear polarized (LP) through a reasonable feeding mode. By adjusting the equivalent length of the unit cell, the Q value of the antenna can be reduced, resulting in the increase of the bandwidth of the array. The array consists of seven-unit cells and dual-port feeding. The unit cells which are connected by a microstrip line are arranged in a circular array. A reasonable layout of unit cells can achieve good port isolation of the array. The polarization performance of the array antenna is the same as that of the unit cell. The antenna is fabricated and measured. The measured results are consistent with the simulated results.

EURADOS project on the impact of the proposed ICRU operational dose quantities.

Following the publication of the joint The International Commissions on Radiation Units and Measurements (ICRU) and on Radiological Protection (ICRP) report on new operational quantities for radiation protection, the European Dosimetry Group (EURADOS) have carried out an initial evaluation. The EURADOS report analyses the impact that the new quantities will have on: radiation protection practice; calibration and reference fields; European and national regulation; international standards and, especially, dosemeter and instrument design. The task group included experienced scientists drawn from across the various EURADOS working groups.

Assessment of the impact on a PADC neutron dosimetry system of the new operational dose quantities proposed in ICRU report 95.

The International Commission on Radiation Units and Measurements, ICRU, have recommended, in ICRU Report 95, the adoption of new operational quantities for use in radiation protection monitoring. Their implementation will pose problems for instrument manufacturers supplying area dosemeters and for individual monitoring services providing personal dosemeters for radiation workers. The problems arise for photon, neutron and beta dosimetry, but this paper deals solely with neutron personal dosemeters based on poly-allyl diglycol carbonate (PADC) plastic. It presents information on the problems to be expected based on data from calibrations of actual personal neutron dosemeters in terms of the existing dose quantities.

New operational quantities (RBE × D p lens/Φ) for eye lens neutron dosimetry as a function of energy and angle of incidence in the ICRU 95 formalism

This paper is a continuation of a study published recently by the authors. It presents and discusses computed personal absorbed dose in the lens of the eye (D p lens/Φ), and a relative biological effectiveness (RBE)-weighted absorbed dose (in terms of an newly proposed operational quantity RBE × D p lens/Φ), conversion coefficients for the lens of the eye for neutron exposure at incident energies from thermal to ∼20 MeV and at angles of incidence from 0° to 90° in 15° increments, at 180° and for rotational incidence irradiation geometry (from 0° to 360° in 5° increments). These conversion coefficients were obtained from a simulation model developed for this study that contains the stylised eye model, embedded in the adult UF-ORNL mathematical phantom, whereby the previously stated RBE-weighted absorbed dose was obtained using the proposed RBE versus neutron energy distribution compiled in a previous paper by the authors. The simulations carried out for this study using the Monte Carlo N-Particle transport code version 6.2, were conducted in a realistic human eye model, for the left and right sensitive and whole volume of the lens of the eye, considering the recent proposed redefinition of the operational quantities for external radiation exposure in International Commission on Radiation Units and Measurements (ICRU) report 95. A comprehensive set of tabulated data for neutron fluence-to-dose conversion coefficients (D p lens/Φ in pGy cm2) and RBE-weighted absorbed dose (RBE × D p lens/Φ in pGy cm2) conversion coefficients is included in this paper as a function of incident neutron energy and angle of incidence. Data for D p lens/Φ (pGy cm2) are compared to similar data from the literature for validation of our model. Data for RBE × D p lens/Φ (in pGy cm2), were also compared to the equivalent operational quantity H p(3,α)/Φ (in pSv cm2) conversion coefficients calculated at 3 mm depth in a cylindrical phantom for different incident neutron energies and angles of incidence from 0° to 75° in 15° increments to demonstrate the relevance of this newly proposed operational quantity for doses resulting in tissue reactions (deterministic effects) which should be quoted in Gray (RBE-weighted absorbed dose, RBE × D (Gy)), rather than Sievert (Sv) which is reserved for stochastic effects. The current neutron weighted absorbed dose (RBE × D p lens) is proposed for the tissue reactions in the eye-lens for neutron radiation as per National Council on Radiation Protection and Measurements report 180 and in line with the recent proposal for the review and revision of the System of Radiological Protection to Keeping the International Commission on Radiological Protection (ICRP) recommendations fit for purpose. This method would bring better alignment between the dose limits in ICRP 118 and the new operational quantity consistent with the units of the new eye-lens dose limits without being overly conservative. The utilization of the proposed new operational quantities, as outlined in ICRU 95, has the potential to address the ongoing challenge in enforcing regulatory limits for neutron eye dose, specifically the use of Gy instead of Sv. It should be noted that the applicability of this will vary from country to country as in many countries the legislation is likely to mandate the use of H p(3) until the regulation is amended. This approach can serve as an interim solution while awaiting the issuance of the new ICRP general recommendations, which is expected to take several years. Implementing the new operational quantities can contribute to enhancing the accuracy and effectiveness of neutron eye dose limit enforcement.

Wedge Filter Variation on Wedge Factor in Patients Cancer Breast in Sub Installation Radiotherapy RSUP Prof. Dr. I.G.N.G Ngoerah

The aim of the study was to determine the effect of irradiation time, the percentage of the maximum dose, the distribution of doses at the center point, and the wedge factor on wedge filter variations. The research method uses a wedge filter to measure irradiation time, maximum dose percentage, dose distribution at the center point, and the wedge factor. Wedge value factor without wedge, wedge 15 , wedge 30, wedge 45and wedge 60of 1.000, 1.0059, 1.0102, 1.0137, and 1.0092 respectively. The results of the maximum dose percentage values without wedge, wedge 15 , wedge 30 , wedge 45and wedge 60were 106.76%, 106.80%, 106.79%, 106.85%, and 106.81%, respectively. Conclusion is the value of the wedge factor does not comply with the ICRU standard but the percentage of the maximum dose is in accordance with the International Commisson on Radiation Units (ICRU) standard, there is a wedge effect factor, and irradiation time on the variation of the wedge filter, but there is no effect of the maximum dose percentage and distribution at the center point on the variation of the wedge filter.

Heavy-ions shielding data for hadrontherapy application with Monte Carlo methods.

In hadrontherapy centers, ion beams are accelerated by a cyclotron or synchrotron through electric and magnetic fields and, once the treatment energy is reached, ions interact with the patient. The interaction of the beam with magnets, other elements of particle accelerator or with the patient generates secondary radiation and the calculation for the design of the shielding is required. A first assessment of the shielding, generally made by concrete, can be performed by using Monte Carlo simulations, in which neutron yields and the ambient dose equivalent, H*(10), spatial distribution are obtained. The aim of this work is to evaluate, with a Monte Carlo approach, ambient dose equivalent values at various concrete depths generated by the secondary radiation. Simulations are performed considering helium, lithium, carbon, oxygen and iron primary beams. For existing facilities that already accelerates carbon ion, an equivalent carbon ratio is introduced to estimate the ion currents to get, in a given point, the same ambient dose equivalent as a carbon ion. Numerical results have been obtained simulating an ion beam that impinges on a thick iron or international commission on radiation units and measurements (ICRU) tissue, respectively, representing magnets and patient. The secondary radiation is transported through a large concrete shielding where ambient dose equivalent values are calculated as function of concrete thickness.

Planning Target Volume Margin Determination for Volumetric Modulated Arc Therapy Planning in Cervix Cancers Using an Empty Bladder Protocol

OBJECTIVE To evaluate the planning target volume (PTV) margin and bladder volume variation of volumetric modulated arc therapy (VMAT) in cervical cancer using an empty bladder protocol. METHODS Ten patients with cervical cancer who had indications to receive whole pelvic radiotherapy and who had been identified to receive whole pelvic irradiation with a dose of 46-55.2 Gy in 23 fractions planned by VMAT were included. International Commission on Radiation Units and Measurements (ICRU) Report 83 was used to report plan parameters. The empty bladder protocol is designed for use with all patients before simulation and irradiation. From June 2020 to February 2021, 215 fractions from the 10 patients were evaluated. The ‘all fraction’ set-up errors were recorded using cone-beam computed tomography (CBCT) and were interpreted as error margins using the Van Herk Formula. RESULTS The calculated PTV margins were 0.75, 0.84, and 0.98 cm on the X, Y, and Z-axes, respectively. The median volume of the bladder before irradiation was 40.6 cc, with an interquartile range of 31.9 to 59.2 cc. The average change in bladder volume from the planning volume was 23.56%. CONCLUSIONS Using the empty bladder protocol, the clinical target volume (CTV) to PTV margin was 1 cm following the Van Herk formula. No patients experienced side effects of grade 3 or greater. The empty bladder protocol is a method which can reduce target placement error and reduce patient discomfort without causing serious side effects. KEYWORDS PTV margin, VMAT, IGRT, Cervix cancer, Empty bladder

Prompt gamma ray activation analysis for determining chemical composition of 3D printing and casting materials used in biomedical applications.

Three-dimensional printing and casting materials were analyzed by prompt gamma-ray activation analysis (PGAA) to determine their suitability as human tissue surrogates for the fabrication of phantoms for medical imaging and radiation dosimetry applications. Measured elemental compositions and densities of five surrogate materials simulating soft tissue and bone were used to determine radiological properties (x-ray mass attenuation coefficient and electron stopping power). When compared with radiological properties of International Commission on Radiation Units and Measurements (ICRU) materials, it was determined that urethane rubber and PLA plastic yielded the best match for soft tissue, while silicone rubber and urethane resin best simulated the properties of bone.

Safety measures among workers occupationally exposed to ionizing radiation in hospitals in AL-Muthanna Governorate, Iraq

Background: Health professionals working in the radiological departments of Al-Muthnia Hospital are at high risk of radiation exposure due to a lack of personal protective equipment (PPE) such as thyroid shields, genital shields, and lead glass in all radiological departments, as well as a lack of staff awareness of the need to use these PPI. A study of the extent of the use of personal protective equipment (PPE) for radiation workers in hospitals. Method: To determine the scope of radiation workers' obligations in hospitals about wearing personal protective equipment, a cross-sectional investigation was carried out among participants in All Radiation Units in Hospitals in the AL-Muthana Governorate. Results: This study involved 95 participants from radiological units 95 people responded overall. Their average age was 37 years, 70.5 percent of them were men, 33.0 percent of them worked as radiographers in x-ray units, the majority of them were married, and 41.1% had diplomas or other credentials. According to the study, only 45.4 percent of staff members wear PPE(lead coat) when dealing with radiation, while 50.9-92 percent of staff members report that additional PPI, including lead glasses, genital shield, and theroid shield, are unavailable. Occupational health and safety training is only provided to 63.2 percent of the staff. At a P value of 0.05, all questions are statistically significant. Study objective: Identify the extent of the obligations of radiation workers in hospitals in terms of wearing personal protective equipment.

Design of a High-Gain Hybrid Slot Antenna Array Based on Bulk Silicon MEMS Process for W-Band Applications

A W-band, high-gain, hybrid slot antenna array based on bulk silicon MEMS technology is proposed in this paper. The high-order-mode cavity is explored to excite the 2 × 2-slot basic unit, so as to reach the low-profile requirement of the bulk silicon MEMS process. To avoid the fragile structure of the large-scale antenna arrays based on the bulk silicon MEMS process, the ridge gap waveguide is employed to build the feed network for a large-scale array. A vertical transition between a rectangular waveguide and a ridge gap waveguide is designed to support the low-loss and low-cost assembling method between the radiation units and the feed network. An 8 × 8-slot hybrid antenna array is simulated and fabricated. The measured results show a relative bandwidth (VSWR < 2) of 8.1% with the first side-lobe level less than −11 dB over the frequency band of 91–97 GHz. A maximum gain of 26.1 dBi with the radiation efficiency of 65.2% is achieved. With high gain and high fabrication efficiency, the proposed hybrid slot antenna array would be valuable for W-band radar applications.

WORKFLOW CHANGES & RESPONSIBILITIES CONCERNING USER APPLICATION OF TOMOTHERAPY OVER LINEAR ACCELERATOR, A RADIATION THERAPIST STANDPOINT

Radiation Therapist's (RTT) role in the driven modern Technology is rapidly evolved day by day, with the new advancement through Articial Intelligence involvement making errors less efcient time effective workow, but at the end of the day, there is a signicant of Radiation Therapist who is responsible for mastering the high Complex Radiation dose Delivery. Linear Accelerator (LA) known as a linear particle accelerator has many applications such as they generate X-rays and high-energy electrons for Radiation therapy, Treatment purposes used directly to achieve the highest kinetic energy for light particles for particle physics. Ionizing in medicine works by damaging the DNA of cells including cancer cells. We can this is the primary radiation Unit for treating cancer patients. Most Radiation Therapists have basic user guidelines to Operate the C-arm Linear accelerator, On the Otherhand, The Tomotherapy System is among the most revolutionary radiotherapy innovations in the history of cancer treatment, completely redening the standard for individualized and precise treatment of tumors anywhere in the body ,while creating a new paradigm for patient comfort and quality of life. Tomotherapy combines integrated CT imaging for exceptional treatment accuracy with a rst-of-its-kind helical treatment delivery platform that uses patented beam-shaping technology to precisely target tumors while minimizing the impact on surrounding healthy tissue. There are various Operational Changes as compared to the traditional LA where Radiation Therapist needs to adapt themselves to these signicant Changes The aim of this paper is to briey describe the new generation of Tomotherapy Radiation Therapists point of view and the changes in the regular workow towards the high-end treatment modality.

Heterogeneous breast phantom for computed tomography and magnetic resonance imaging.

In this article, a heterogeneous multimodal anthropomorphic breast phantom with carcinoma is introduced to meet the response of the natural breast tissue when imaged using ionizing and non-ionizing machines. The skin, adipose, fibroglandular, pectoral muscle, and carcinoma tissue were mimicked. A T1-weighted breast magnetic resonance image with BI-RADS I tissue segmentation was used for molds creation. The tissue-mimicking materials (TMMs) were tailored in terms of their elemental composition weight fractions and their response to ionization radiation parameters. These are the mass attenuation coefficient (MAC), electron density (ne) and effective atomic number (Zeff). The behaviour of the TMMs, when exposed to a wide range of ionization radiation energy, was investigated analytically and numerically using X-COM. The achieved results showed an excellent agreement with the corresponding properties of the natural breast elemental compositions as reported by the International Commission on Radiation Units and Measurements (ICRU). The MAC of the TMMs and the ICRU-based breast tissue were found to be consistent. The maximum percentage of error in ne and Zeff amounts to only 2.93% and 5.76%, respectively. For non-ionizing imaging, the TMMs were characterized in term of T1 and T2 relaxation times. Using our preclinical MRI unit, the TMMs relaxation times were measured and compared to the natural tissue. The fabricated phantom was validated experimentally using CT, MRI, and Mammographic machines. The achieved images of the TMMs were in alignment with the real tissue in terms of CT HU values and grayscale colors. T1W and T2W images on MRI revealed the expected contrast between TMMs as in natural tissue.

Integrated Small Animal PET/CT/RT with Onboard PET/CT Image Guidance for Preclinical Radiation Oncology Research.

We have integrated a compact and lightweight PET with an existing CT image-guided small animal irradiator to enable practical onboard PET/CT image-guided preclinical radiation therapy (RT) research. The PET with a stationary and full-ring detectors has ~1.1 mm uniform spatial resolution over its imaging field-of-view of 8.0 cm diameter and 3.5 cm axial length and was mechanically installed inside the irradiator in a tandem configuration with CT and radiation unit. A common animal bed was used for acquiring sequential dual functional and anatomical images with independent PET and CT control and acquisition systems. The reconstructed dual images were co-registered based on standard multi-modality image calibration and registration processes. Phantom studies were conducted to evaluate the integrated system and dual imaging performance. The measured mean PET/CT image registration error was ~0.3 mm. With one-bed and three-bed acquisitions, initial tumor focused and whole-body [18F]FDG animal images were acquired to test the capability of onboard PET/CT image guidance for preclinical RT research. Overall, the results have shown that integrated PET/CT/RT can provide advantageous and practical onboard PET/CT image to significantly enhance the accuracy of tumor delineation and radiation targeting that should enhance the existing and enable new and potentially breakthrough preclinical RT research and applications.

Implementation of online workshops on image-guided adaptive brachytherapy (interventional radiotherapy) in locally advanced cervical cancer: Experience of BrachyAcademy

PURPOSETo provide educational support to brachytherapy users during the COVID-19 pandemic, online workshops were developed and implemented by BrachyAcademy, non-profit peer-to-peer educational initiative in Elekta. METHODS AND MATERIALSIn 2021–2022 two online workshops were organized. Participating teams had to send a clinical case of locally advanced cervical cancer (LACC) including brachytherapy Digital Imaging and Communications in Medicine (DICOM) files and questions to the faculty. During the workshop, feedback was given to each clinical case by five faculty members (two Radiation Oncologists, one Radiologist, two Medical Physicists). Participants competed a post-workshop questionnaire which included combination of qualitative and quantitative questions via yes/no responses, Likert scale, and 1 to 10 scale. RESULTSTwenty-one teams from eight countries (Europe, Asia, Latin America) participated in two online workshops. The total number of participants was 49. The clinical cases represented LACC with The International Federation of Gynecology and Obstetrics (FIGO) stages from IB3 to IVA. During both, Workshop1 (W1) and Workshop 2 (W2) the following areas of improvement were identified: familiarity with the GEC ESTRO and The International Commission on Radiation Units & Measurements, Report 89 (ICRU 89) recommendations for contouring and planning based on clinical drawings and MRI sequencing choice; appropriate applicator selection; experience with interstitial needles; appropriate applicator reconstruction; dose optimization. The participants rated both workshops with overall scores 8,3 for W1, and 8,5 for W2. In 82% participants the training course fully met expectations for W1, and in 76% in W2. CONCLUSIONSWe successfully implemented the online workshops on image-guided adaptive brachytherapy (IGABT) in LACC. Main performance issues and areas for improvement were identified based on multidisciplinary discussion of participant's clinical cases through all steps of the brachytherapy procedure. We encourage teams to consider online workshops in addition to hands-on training.

Study on Optimization of Copper to Aluminum for Locomotive Finned Tube Radiator

The influence of the improvement of the finned tube radiator unit structure on the fluid flow and heat transfer effect of the locomotive was studied. A saw-toothed fin structure with aluminum instead of copper was proposed to keep the position and size of the flat copper hot water pipe unchanged. CFD simulation analysis was carried out by ICEPAK17.0, under the conditions of an ambient temperature of 24.6 °C, atmospheric pressure of 85,040 Pa and air density ρ = 0.94 kg/m3, to compare the changes of velocity field, temperature field, turbulence field and field synergy angle. The sawtooth structure of the new heat sink increases the turbulence effect of the fluid, reduces the thickness of the outer boundary layer of the water pipe, and strengthens the heat transfer effect of the radiator. Finally, the baffle height, wing window width and sawtooth angle of the sawtooth structure were selected, and the heat transfer coefficient and pressure under three conditions of low, medium and high were used as indexes to analyze the influence of each parameter on the performance of the radiator. The results show that the heat dissipation effect of the serrated aluminum sheet is higher than that of the copper sheet, the heat transfer coefficient is increased by about 1.3%, the average pressure is reduced, the turbulence performance is improved, the synergy angle is reduced by about 2.3°, and the new radiator has better performance. The fin factor has the greatest influence on the heat transfer coefficient and the least influence on the pressure. When the baffle is about 0.15 mm high, the heat transfer coefficient is the largest, and the height change has the highest effect on the pressure. The included Angle factor has the least influence on the heat transfer effect, and the influence on the pressure is higher. By changing the fin window structure, the thermal performance of the finned tube radiator can be improved.

Impact of the implementation of the new radiation quantities recommended by ICRU/ICRP for practical use in interventional radiology: a Monte Carlo study

The International Commission on Radiation Units and Measurements (ICRU) proposed a new set of operational quantities for radiation protection for external radiation in its Report Committee 26 (ICRU 95). The new proposal aims to improve the coherence between the operational quantities and the definitions of the protection quantities in the recommendations of the International Commission on Radiological Protection set out in 2007 (Ann. ICRP 37). It is expected that this change in operational quantities will impact current dosimeter designs. Although for many photon energies, the conversion coefficients from physical field quantities to the new operational quantities will change relatively little, for radiation fields with low energy photon components, such as medical x-ray applications, there will be a significant decrease in the values of the conversion coefficients. This means that the numerical values of the new operational quantities will be much lower for the same radiation field. These values will be closer to the effective dose, but this change can still cause confusion for medical staff. It is important to examine the effect of the new set of dose conversion coefficients on the personal dose in realistic radiation fields. We performed a study to assess the effect of changing the definition of the operational quantity, personal dose equivalent (), in realistic radiation fields in interventional radiology (IR) workplaces. The x-ray tube kilovoltage peak (kVp) in IR ranges between 60 and 120 kV. The medical staff is exposed to the scattered photons which have a wide range of energies depending on the beam configuration and the patient size. The objective of this study is to ‘quantitatively’ estimate the impact of implementing the new ICRU quantities of Report 95 in IR radiation fields using Monte Carlo simulations. Simulations of 560 different configurations in IR were performed using MCNPX to calculate fluence binned per energy and angle of incidence. and were then calculated for each configuration using dose conversion coefficients from fluence given by ICRU Reports 95 and 57, respectively. The results show that the mean of the ratio, , is 1.6 for all simulated scenarios. This reduction will correct the current overestimation of the effective dose and should result in better compliance with the dose limits in IR. However, it may also have negative consequences on the safety culture among the medical staff. Special care will be needed when interpreting these lower doses.

A universal UHF near‐field RFID reader antenna with wide bandwidth and adjustable reading area

AbstractA universal ultrahigh‐frequency (UHF) near‐field radio‐frequency identification (RFID) reader antenna with wide bandwidth and adjustable reading area is proposed in this letter. The antenna consists of an inverting power splitter base on double‐sided parallel stripline and adjustable traveling‐wave near‐field radiation units, which consists of two symmetrical meander microstrips and a complementary open resonant ring loaded on the ground plane. A design example with three radiation units is simulated, fabricated, and tested for verification. The result indicates that the proposed antenna has the 10‐dB impedance bandwidth of 128%, which completely covers the universal UHF RFID band from 840 to 960 MHz. The 100% read–write rate is achieved within the read–write distance of 10 mm according to the reading test. The reading area of 731 × 120 mm2 can be obtained for increasing the number of radiation units to 10. Moreover, the antenna features low far‐field gain, low‐cost, strong and uniform magnetic field distribution. Therefore, the proposed antenna and design method have good application prospects in the Internet of Things.

Assessment of the awareness of radiation protection and related concepts among nursing staff mainly working in diagnostic imaging units, cath-labs and operation theatres in Sri Lanka: A survey-based study

IntroductionThis study was carried out to evaluate the awareness of radiation protection, radiation types, medical imaging equipment and radiation effects among nurses for the first time in Sri Lanka. Since nurses are involved as direct caregivers in diagnostic and therapeutic radiography and radiation treatment procedures, they need to have a good understanding of the areas mentioned above. MethodsA self-administered questionnaire was used to collect data from 391 nurses working in hospitals, clinics, and other healthcare settings. Forwarded questions gathered the participants' demographic details and assessed their awareness of radiation protection, medical imaging equipment, radiation type and radiation effects. The average score per awareness area for each demographic characteristic was calculated based on the responses. Additionally, the percentage of participants who scored above 50 and 75 was calculated for each awareness area. ResultsThe majority were female participants (81.1%) and possessed a diploma in nursing (66.0%) with 10.8 years of average work experience. 92.3%, 74.7%, 69.8% and 22.3% of the participants scored more than 50 marks for the questions related to radiation protection, medical imaging equipment, radiation type and radiation effects, respectively. The level of nursing education and prior training in radiation protection significantly influenced all awareness areas, whereas participants with a graduate qualification in nursing and with prior radiation protection training scored the highest average marks. ConclusionBased on the scores obtained, the Sri Lankan nurses have satisfactory awareness of the essential concepts related to radiation types, medical imaging equipment and radiation protection. However, there is a significant lacking of awareness of radiation effects. This can be attributed to the fact that most participants did not have any formal training in radiation protection. The results implicate that proper training in radiation protection can significantly influence awareness of radiation protection and related concepts. Therefore, it is a timely requirement to initiate short awareness programs and continuing education programs on radiation protection for nurses working in specialised radiation units. Implications for practiceThe study suggests the necessity of initiating continuous education programs for nursing staff radiation protection to overcome the awareness gaps.

Methods of dosimetry-based treatment planning in radiopharmaceutical therapy. Part 2: Planning levels

At the present time three most common approaches are used for the planning of the radionuclide therapy: administration of the fixed activity of radionuclide in radiopharmaceutical, or administration of activity normalized per unit of body mass or body surface. That may lead to significant deviations between the prescribed and real absorbed doses in healthy organs and tissues. These deviations are associated with differences in biodistribution and pharmacokinetics of radiopharmaceutical between models and real patients. That does not allow individual planning of the treatment course for each patient since data on the accumulated activity in source regions and organs at risk is limited and uncertainty is too high for the calculation of absorbed doses. Improvements in the reliability of the absorbed dose calculation can be achieved through the use of different imaging modalities (diagnostic nuclear medicine) for the quantitative assessment of accumulated activity of radionuclides in organs and tissues and distribution of radiopharmaceutical in healthy tissues. Planning of radionuclide therapy should be personalized. The current study was aimed at the analysis of the approaches the dosimetry-based planning of radionuclide therapy presented in the Report of International Commission on Radiation Units and Measurements 96 «Dosimetry-guided radiopharmaceutical therapy», differentiated based on the possibilities of the nuclear medicine departments, including examples of levels of planning for most common radiopharmaceuticals. The results of analysis indicated that most optimal approach for Russian clinical practice is to transit to the requirements of planning level 1: to calculate and report administered activity considering patient body mass, type and stage of disease was well as prescribed clinical task. Requirements of planning level 2 are currently impossible to implement nation-wide, except for several nuclear medicine research facilities. Additionally, it is necessary to focus on the development of the methods of estimation of absorbed doses in major delineable organs.