External Radiation Research Articles

Ultracold atomic spin mixtures in ultrastable magnetic field environments

Ultracold atomic spin mixtures develop rich and intriguing magnetic properties when external radiation coherently couples different spin states. In particular, the coupled mixture may acquire a critical behavior when the spin interactions equal the coupling energy. However, atomic mixtures generally feature a relatively high sensitivity to magnetic fields that can set a limitation to the observable phenomena. In this article, we present an overview of experimental studies of magnetism based on superfluid multicomponent gases in an ultrastable magnetic field environment, which recently became available.

The spatial pattern and association network of green finance development: Empirical evidence from China

AbstractGreen finance is a market‐driven approach to achieve the “double carbon” goal. However, the existing research predominantly focuses on the connotations and empowerment aspects of green finance. Notable regional disparities exist in China's financial markets and resource endowments, resulting in uneven levels of green finance development among various areas, significantly impeding the overall green transformation of the economy and society. In light of this, our paper explores the spatial patterns and association network of green finance development in China. The research findings indicate that: (1) The development of green finance in China exhibits an “east high, west low” spatial distribution pattern, with significant spatial clustering observed among neighboring provinces. The eastern region displays a “H‐H” clustering, while the western region shows an “L‐L” clustering. (2) The spatial correlation distribution of provincial green finance in China demonstrates an eastward concentration and westward dispersion trend, with strong correlation areas gradually expanding. Notably, Jiangsu, Zhejiang, Shanghai, and the Beijing‐Tianjin‐Hebei urban agglomerations lead nationally in attractiveness. (3) The external radiation capability of provincial green finance is progressively improving, with provinces such as Beijing, Hebei, Hubei, and Sichuan likely to occupy strategic structural positions, possessing greater development advantages. This study not only expands the theoretical scope of existing green finance research but also provides a practical reference for coordinating and achieving the high‐quality development of regional green finance from a practical perspective.

Distance‐Driven Terahertz Metallic Metasurface Supporting QGM in the Continuum

AbstractThe metasurfaces that support high‐Q resonances can provide ultra‐sharp resonance and achieve strong light‐matter interaction, which promotes their application in various fields such as sensing, lasing, and imaging. Bound modes, unable to radiate into free space, can be transformed into quasi‐bound modes and coupled with external radiation, achieving high‐Q resonances. For periodic structures, by introducing appropriate periodic perturbations, the guided modes (GMs) below the light line can be exposed above the light line, forming the high‐Q quasi‐guide modes (QGMs). Herein, a metallic metasurface is designed that supports the QGM in the continuum by introducing the Brillouin zone folding strategy. The simulation and experiment demonstrate that the GM below the light line can be transformed into the QGM in the continuum by tuning the distance parameter, and a typical “electromagnetic‐induced transparency‐like (EIT‐like)” spectrum is observed. The design unlocks additional degrees of freedom for generating high‐Q metallic metasurface. The advantage of avoiding the production of asymmetric defects contributes to releasing the strict requirement on manufacturing precision. The combination of the metallic metasurface supporting QGM resonance with high‐Q factors and the flexible substrate can improve the performance of the flexible devices and broaden its application in terahertz optoelectronic devices.

Monocentric Retrospective Study: Efficacy, Feasibility, and Prognostic Factors of Single-Insertion High-Dose-Rate Brachytherapy With 4 Sessions for Locally Advanced Cervical Cancer

ObjectiveThis study aims to assess the feasibility and efficacy of high-dose-rate (HDR) brachytherapy (BT) administered in a single insertion with four treatment sessions for locally advanced cervical cancer (LACC), and to identify the prognostic factors influencing outcomes. MethodsWe retrospectively analyzed the clinical data of cervical cancer patients with locally advanced disease (International Federation of Gynecology and Obstetrics 2018 (FIGO) IB-IVB), treated at our institution from January 2014 through December 2021. Each patient received definitive radiotherapy with an external irradiation dosage between 45-50.4 Gy along with concurrent chemotherapy (CCRT). HDR-BT (24 Gy) was prescribed to a high-risk clinical target volume (HR-CTV). Results139 patients were included and HDR-BT program could be fully performed in 136 patients (98%). Over a median follow-up duration of 40.5 months, the two-year local control (LC), overall survival (OS), and disease-free survival (DFS) rates stood at 79.4%, 77.7%, and 61.7% respectively, with five-year rates at 78.2%, 61.6%, and 55.7%. Multivariate analysis revealed the primary determinant of LC as the tumor's response to external beam radiotherapy (EBRT) as determined via magnetic resonance imaging (MRI) prior to BT. Parametrial involvement demonstrated a significant multivariate association with DFS (p = 0.04). Regarding OS, parametrial invasion (p = 0.01) and the tumor's response post-chemoradiotherapy (p = 0.02) emerged as significant factors. Regarding chronic toxicities, 18% (25 patients) experienced grade 3 complications. An optimal D2cc (Bowel) threshold of 70 Gy (p = 0.001) was identified to limit chronic digestive complications of grade 3 or higher. ConclusionThe implementation of single-insertion, four-session HDR-BT could be performed in 98% of the patients. It yields favorable LC and OS rates, coupled with tolerable toxicity in patients with LACC. Response to initial chemoradiotherapy evaluated on pre-BT MRI is an important prognostic factor and could help to individualized therapeutic strategies.

Plasma confinement by an optoelectronic system

Plasma confinement was succeeded by an optoelectronic system with the aid of a vacuum ultraviolet (VUV) light source, called the photoemission-assisted plasma system. The photoemission-assisted plasma was generated by utilizing photoelectrons from the substrate cathode. The photoelectrons were emitted from the substrate by external VUV irradiation via the photoelectric effect and then worked as initial electrons triggering the plasma generation. The photoemission-assisted plasma was confined with bright luminescence in an argon atmosphere by controlling the flow rate and pressure. The plasma confinement survived at up to 6400 Pa, which was much higher than the pressure estimated from the current–voltage characteristics. These results suggested that the area exhibiting luminescence dominated by the γ regime becomes small as the argon flow rate increases; however, the area does not vanish because the VUV-excited photoelectrons are sufficiently supplied. The residual area is dominated by the α regime without luminescence. Thus, the photoemission-assisted plasma seems to be confined on the balance between α and γ regimes. Because the current in the α-regime area is one hundredth in magnitude compared with that in the γ-regime area, the actual current density results in over 40 times with strong luminescence. This confined plasma with certain voltage and current condition may be expected for developing a new plasma reaction system and for application in semiconductor engineering.

Photoresponsive Janus microfibers array film with tunable electrical anisotropy

A new kind of photoresponsive film is produced by integrating photoconductive material into the type-II anisotropic conductive film. This film consists of orderly arranged Janus microfibers, with each Janus microfiber is comprised of a conductive region and an insulating region. Copper phthalocyanine, as the photoconductive material, is introduced into the conductive regions of these Janus microfibers, and thus the electrical conduction of the conductive regions can be enhanced by applying appropriate external light irradiation, while the insulating regions are basically unaffected. Based on this property, the electrical conduction along with the length direction of the Janus microfibers in the film is adjustable by light, the perpendicular direction along the film surface remains constantly insulating, and thus the electrical anisotropy of the resulting Janus microfibers array film can be tuned under light irradiation. The products have potential applications in flexible electronic devices and control systems.

Investigation of the stability in the performance of triple GEM detectors for High Energy Physics experiments

Gas Electron Multiplier (GEM) is one of the mostly used technologies in the High Energy Physics (HEP) experiments. GEMs are widely used as tracking devices due to their high-rate handling capability and good position resolution.An initiative is taken to study the stability in performance of the GEM chamber prototypes in the laboratory using external radiation for Argon/CO2 gas mixture in 70/30 volume ratio. The effect of ambient parameters on the gain and energy resolution are studied. Very recently some behavioural changes in the performance of a single-mask GEM chamber is observed. The details of the experimental setup, methodology and results are reported here.

Radiation Therapy for Non-Melanoma Skin Cancer: A Study of 63 Cases

Cutaneous carcinomas are the most common skin cancers. Our work aims to identify the epidemiological and clinicopathological characteristics of cutaneous carcinomas, especially squamous cell carcinomas and basal cell carcinomas, treated and monitored at the Oncoradiotherapy Department of the Mohammed VI University Hospital of MARRAKECH, treated with radiotherapy, and to evaluate their efficacy and tolerance. Our study is retrospective and descriptive. We collected data from 63 patients treated and monitored between 2019 and 2022 at the Marrakech University Oncohematology Hospital. For each patient, we collected epidemiological, clinicopathological, therapeutic, and evolutionary data using an exploitation form. The age of the patients ranged from 27 to 95 years, with a peak between 61 and 70 years and a median of 64.32. Males predominated (74.6%). The matte skin phenotype was the most common, present in more than half of the patients. Among 63 patients surveyed, 69.8% had a history of prolonged sun exposure. Tumors of the head and neck were found in 65% of cases, with clinical appearance varying: 36.5% ulcerative-budding, 31.7% budding, 22.2% nodular, 6.4% sclerodermiform, and 3.2% ulcerated. Recurrences accounted for only 27% of consultations, and precancerous lesions were found in only 16% of patients. Most patients consulted at locally advanced stages (68.2%). Histologically, squamous cell carcinoma was confirmed in 63.5% of patients. External radiotherapy was performed in all patients, using three-dimensional conformal technique, adjuvant in 77.7% of cases, exclusive definitive in 19%, and palliative in 3.2% of cases. No patient received brachytherapy. Acute complications were observed in 52% of cases and late complications in 8%. After an average follow-up of 2 years, 76% of patients are still being followed in good disease control status with a complete response in 83% of them, 11% local recurrence, and 6% distant metastases. The incidence of cutaneous ........

Surgical management of rectal cancer with synchronous treatment of prostate cancer.

To assess the safety and efficacy of synchronous treatments for rectal (RC) and prostate (PC) cancers. Single-center retrospective study (2007-2021) of patients treated with neoadjuvant radiotherapy (RT) and total mesorectal excision (TME) for RC with synchronous PC treatment. The endpoints were 30-day postoperative severe complications, R0 resection rates, 3-year disease-free survival (DFS) and 3-year overall survival (OS). Among the 16 patients, 15 (93.7%) received neoadjuvant pelvic RT (40-50.4 Gray) followed by either transperineal high dose rate prostate brachytherapy (62.5%), prostate external RT boost (25.0%), or androgen deprivation therapy (ADT) alone (6.3%). One (6.3%) patient received neoadjuvant rectal brachytherapy and ADT. Pelvic RT was combined with chemotherapy in 87.5% of cases. TME was performed in all patients with low anterior resection (87.5%) or abdominoperineal resection (12.5%), primarily using minimally invasive surgery (87.5%). The R0 resection rate was 93.8%. Six (37.5%) patients experienced 30-day Clavien-Dindo grade IIIb complications, including one (7.1%) anastomotic leak. After a median follow-up of 39.0months, 63.6% of diverting ileostomies were reversed. Three-year DFS from RC was 71.4% (CI 40.2-88.3) and 3-year OS was 84.4% (CI 95% 50.4-95.9). No PC recurrence or death occurred. Synchronous management of RC and PC with pelvic RT followed by curative prostate RT doses and TME showed acceptable morbidity and oncologic results. Prostate brachytherapy, the most commonly used treatment modality, allowed avoidance of prostatectomy and additional external RT to the rectum. PC should not limit the curative intent of RC, as all recurrences were from rectal origin.

Current status of reference location in the basic model for assessment of external radiation doses to the population living in radioactively contaminated areas after the Chernobyl accident

An open plot of virgin land is the reference location in the basic model used to date to estimate the effective dose of external exposure to the population living in a radioactively contaminated area. As our field observations in the Bryansk region of Russia have shown, at present it is very difficult to find truly reference plots of virgin land due to the fact that many virgin meadows were plowed or reclaimed for more than 30 years after the Chernobyl accident. Without special instrumental survey, such disturbed meadow areas can easily be confused with areas of virgin soil. Therefore, the situation with the use of open areas of virgin soil as the reference location has changed dramatically since the first years after the Chernobyl accident. It requires a change in the approach to choosing such a location for the model and/or some revision of the structure of the model itself. Firstly, we propose and justify the use of a permanently cultivated kitchengarden plot as the reference location. The second way to resolve the current difficult situation with the presence of a sufficient number of the virgin soil sites could be excluding the very concept of “reference location” from the model. In this case, when calculating the effective dose of external radiation, it is proposed to directly use the values of the gamma radiation dose rate in the air normalized to the 137Cs contamination density of soil. The values of the normalized dose rate should be experimentally determined in the required time period for each of the locations taken into account in the model.

Anti-PD-1 antibody in combination with radiotherapy as first-line therapy for unresectable intrahepatic cholangiocarcinoma

BackgroundUnresectable intrahepatic cholangiocarcinoma (iCCA) has a poor prognosis despite treatment with standard combination chemotherapy. We aimed to evaluate the efficacy and safety of radiotherapy in combination with an anti-PD-1 antibody in unresectable iCCA without distant metastases.MethodsIn this phase II study, patients with histopathologically confirmed unresectable primary or postoperative recurrent iCCA without distant metastases were enrolled. Patients received external radiotherapy with a dose of ≥45 Gy (2-2.5 Gy per fraction), followed by anti-PD-1 immunotherapy (camrelizumab 200 mg once, every 3 weeks) initiated within 7 days after completion of radiotherapy as first-line therapy. The primary endpoint was 1-year progression-free survival (PFS) rate. The secondary end points included safety, objective response rate (ORR), disease control rate (DCR), and overall survival (OS).ResultsFrom December 2019 to March 2021, 36 patients completed radiotherapy and at least one cycle of immunotherapy and were included in efficacy and safety analyses. The median follow-up was 19.0 months (IQR 12.0-24.0), and the one-year PFS rate was 44.4% (95% CI, 30.8-64.0). The median PFS was 12.0 months (95% CI, 7.5-not estimable); the median OS was 22.0 months (95% CI, 15.0-not estimable). The ORR was 61.1% and the DCR was 86.1%. Seventeen of 36 (47.2%) patients experienced treatment-related adverse effects (AEs) of any grade. The most common AE was reactive cutaneous capillary endothelial proliferation (25.0%). Five (13.9%) patients experienced grade ≥3 treatment-related AEs, including decreased lymphocyte (5.6%), bullous dermatitis (2.8%), decreased platelet count (2.8%), and deep-vein thrombosis (2.8%).ConclusionsExternal radiotherapy plus camrelizumab, as first-line therapy, met its primary endpoint and showed antitumor activity and low toxicity levels in patients with unresectable iCCA without distant metastases, warranting further investigation.Trial registrationNCT03898895. Registered 2 April 2019.

Changes of the Vagina After Concurrent Radiochemotherapy and Brachytherapy in Cervical Cancer Anatomical and Physiological Changes

The objective of the study: The aim of our study was to highlight the anatomical and physiological changes of the vagina after external radiotherapy and brachytherapy in cervical cancer. Materials and Methods: This was a prospective descriptive study conducted over a period of 6 months, from March to August 2022. A total of 123 women with cervical cancer, treated with concurrent radiochemotherapy and uterovaginal brachytherapy, who reported having had sexual intercourse in the six months prior, were included in the study. Patients were interviewed and examined during post-therapeutic follow-up consultations. Results and Statistical Analysis: The age of the patients (n=123) ranged from 33 to 67 years, with a mean of 49.35 ± 9.84 years. The post-therapeutic follow-up duration ranged from 6 months to 7 years. The most common histological type was squamous cell carcinoma, and the most common FIGO stage was stage II. Treatment consisted of concurrent radiochemotherapy and uterovaginal brachytherapy. Interviews revealed several changes related to the vagina after treatment. More than 65% of patients (n=81) reported the onset or worsening of vaginal dryness, over 50% (n=63) reported the onset or worsening of dyspareunia. Nearly 70% (n=83) reported a decrease in sexual desire frequency or dissatisfaction, and over 60% (n=78) became indifferent to sexual life. Gynecological examination revealed a vaginal length ranging from 2 to 10 cm with a mean of 5.66 ± 2.09 cm, the presence of synechiae and/or stenosis in nearly 43% (n=53), and bleeding in nearly 40% (n=47). In univariate analysis, vaginal dryness and dyspareunia significantly increased with age. Resumption of sexual activity was slower in younger and older women. Among patients followed for two years or less, there was a significant increase in synechiae or stenosis, as well as bleeding. Conversely, the prevalence of vaginal dryness and dyspareunia increased with follow-up duration, especially in those exceeding two years. In groups with vaginal dryness or dyspareunia, a large proportion of patients reported a decrease in sexual desire and indifference to their sexual life. Conclusion: This study revealed that patients with cervical cancer experienced significant anatomical and physiological changes in the vagina after treatment with concurrent radiochemotherapy and uterovaginal brachytherapy, leading to chronic sequelae and sexual disorders. It is therefore essential to implement measures to prevent or limit certain side effects associated with these treatments.

Applicability of an Ionising Radiation Measuring System for Real-Time Effective-Dose-Optimised Route Finding Solution during Nuclear Accidents

The reduction in the effective dose of evacuated injured persons through contaminated areas of nuclear accidents is an essential emergency services requirement. In this context, there appeared a need to develop a dose-optimised route finding method for firefighting rescue vehicles, which includes the development of a real-time decision support measurement and evaluation system. This determines and visualises the radiation exposure of possible routes in a tested area. The system inside and outside of the vehicle measures the ambient dose equivalent rate, the gamma spectra, and also the airborne radioactive aerosol and iodine levels. The method uses gamma radiation measuring NaI(Tl) scintillation detectors mounted on the outside of the vehicle, to determine the dose rate inside the vehicle using the previously recorded attenuation conversation function, while continuously collecting the air through a filter and using an alpha, beta, and gamma radiation measuring NaI(Tl)+ PVT + ZnS(Ag) scintillator to determine the activity concentration in the air, using these measured values to determine the effective dose for all routes and all kinds of vehicles. The energy-dependent shielding effect of the vehicle, the filtering efficiency of the collective protection equipment, and the vehicle’s speed and travel time were taken into account. The results were validated by using gamma point sources with different activity and energy levels. The measurement results under real conditions and available real accident data used in our simulations for three different vehicles and pedestrians proved the applicability of the system. During a nuclear accident based on our model calculations, the inhalation of radioactive aerosols causes a dose almost an order of magnitude higher than the external gamma radiation caused by the fallout contamination. The selection of the appropriate vehicle and its route is determined by the spectrum that can be measured at the accident site but especially by the radioactive aerosol concentration in the air that can be measured in the area. In the case of radiation measuring detectors, the shielding effect of the carrier vehicle must be taken into account, especially in the case of heavy shielding vehicles. The method provides an excellent opportunity to reduce the damage to the health of accident victims and first responders during rescue operations.

Inclined surface mixed convection flow of viscous fluid with porous medium and Soret effects

Abstract The combined heat and mass transfer phenomenon is a significant aspect of engineering and industrial processes. This phenomenon finds applications in various areas such as air conditioning, cooling and heating control of electronic devices, reactors, chemical systems, and emission processes. This research model focuses on the analysis of mixed convection flow of a viscous fluid with heat and mass transfer on an inclined surface with porous medium characteristics. The study also considers external heat transfer effects, radiation, Soret influence, and chemical reactions. A perturbation solution is derived in closed form, and the impact of various parameters on the thermal behavior is investigated. A comparative analysis of the heating and cooling regimes in plate flow is conducted, revealing a reduction in velocity in the heated plate regime with changes in the permeability parameter and an increase in concentration phase due to the Soret number.

Shortwave infrared polarization characteristics simulation of solid rocket plume with self-emission and external incident radiation

Polarization optical detection has been widely used in the detection and identification of particle containing media such as clouds, aerosols, fire plumes, and volcanic smoke. Solid rocket plume is a typical high-temperature gas–solid two-phase medium. Polarization optical detection of solid rocket plume has attracted much attention in recent years. The polarized radiation transfer mechanism of solid rocket plume is complex, especially in the infrared band, with both the scattering radiation transfer from external incident light and the scattering radiation transfer from the high-temperature region inside the jet flame to the outside. The research on the polarization scattering characteristics of solid jet flame still needs to be further developed. Therefore, this study focuses on modeling the infrared polarization scattering mechanism and the simulation of polarization transfer characteristics of a solid rocket gas–solid two-phase plume, which can guide the usability analysis of solid rocket plume polarization detection. A novel model based on Semi-analytic Monte Carlo Method is proposed to simulate polarized radiation transfer of solid rocket plume. The wavelength and angle dependence of the self-radiation polarization characteristic of a solid rocket plume is simulated based on the proposed model. Note that the overall polarization degree of the plume shows wavelength selectivity and angle sensitivity at different wavelengths. The spatial distribution of polarization degree at 1.55 μm, 2.2 μm, and 2.75 μm shows that the plume edge's polarization degree is higher than the plume center. The findings suggest that the ratios of the relative contribution of self-radiation, direct solar radiation, and background polarization radiation components to the total polarization characteristics are 0.47 %, 70.50 %, 29.03 % at 1.55 μm and 20.43 %, 79.55 %, 0.02 % at 2.75 μm.

Investigation of Photodynamic Therapy Promoted by Cherenkov Light Activated Photosensitizers-New Aspects and Revelations.

This work investigates the proposed enhanced efficacy of photodynamic therapy (PDT) by activating photosensitizers (PSs) with Cherenkov light (CL). The approaches of Yoon et al. to test the effect of CL with external radiation were taken up and refined. The results were used to transfer the applied scheme from external radiation therapy to radionuclide therapy in nuclear medicine. Here, the CL for the activation of the PSs (psoralen and trioxsalen) is generated by the ionizing radiation from rhenium-188 (a high-energy beta-emitter, Re-188). In vitro cell survival studies were performed on FaDu, B16 and 4T1 cells. A characterization of the PSs (absorbance measurement and gel electrophoresis) and the CL produced by Re-188 (luminescence measurement) was performed as well as a comparison of clonogenic assays with and without PSs. The methods of Yoon et al. were reproduced with a beam line at our facility to validate their results. In our studies with different concentrations of PS and considering the negative controls without PS, the statements of Yoon et al. regarding the positive effect of CL could not be confirmed. There are slight differences in survival fractions, but they are not significant when considering the differences in the controls. Gel electrophoresis showed a dominance of trioxsalen over psoralen in conclusion of single and double strand breaks in plasmid DNA, suggesting a superiority of trioxsalen as a PS (when irradiated with UVA). In addition, absorption measurements showed that these PSs do not need to be shielded from ambient light during the experiment. An observational test setup for a PDT nuclear medicine approach was found. The CL spectrum of Re-188 was measured. Fluctuating inconclusive results from clonogenic assays were found.

The Influence of the Heat Transfer Mode on the Stability of Foam Extinguishing Agents

The mass loss mechanisms of an aqueous film-forming foam (AF foam), an AR/AFFF water-soluble film-forming foam extinguishing agent (AR foam), and a Class A foam extinguishing agent (A foam) at different levels of thermal radiation, thermal convection, and heat conduction intensity were studied. At a relatively low thermal radiation intensity, the liquid separation rate of the AF, AR, and A foams is related to the properties of the foam itself, such as viscosity and surface/interface tension, which are relatively independent of the external radiation heat flux of the foam. At low radiation intensity (15 kW/m2 and 25 kW/m2), the liquid separation rate of the AF and A foams is relatively stable. When the heat flux intensity is 35 kW/m2, the liquid separation rate of the AF and A foams increases notably, which may be mainly due to the rapid decrease in foam viscosity. And the mass loss behavior is dominated by liquid separation in the AF, AR, and A foams under the influence of thermal radiation and thermal convection. Under the same experimental conditions, the liquid separation rate of AF is the fastest. There is no significant difference in the evaporation rates of the three kinds of foam in the same heat conduction condition. In addition, the AR and A foams usually have a 25% longer liquid separation time (t) under thermal radiation and thermal convection, and the thermal stability is better than AF foam. The temperature reached by the AF foam layer under thermal convection was lower than that of the AR and A foams, and the time for the foam layer to reach the highest temperature under heat conduction was longer than that of the AR and A foams.

Trends and distribution of external radiation therapy facilities in Japan based on Survey of Medical Institutions from the Ministry of Health, Labour and Welfare.

This study aimed to explore the distribution of external radiation therapy (RT) facilities, the status of related device installations and the adoption of high-precision RT using Survey of Medical Institutions from the Ministry of Health, Labour and Welfare in Japan. Analysis, categorized by the hospital size and prefecture, provides specific insights into the trends in treatment facility healthcare capabilities. Data on the number of RT facilities, high-precision RT facilities, RT devices and treatment planning systems (TPS) categorized by the number of beds and prefecture from 1996 to 2020 were analyzed. In addition, the study examined the correlation between the high-precision implementation rate and the number of TPSs or radiation oncologists and other medical staff. High-precision RT exceeded 95% in large facilities (800+ beds) but remained <50% in medium-sized facilities (300-499 beds). In a prefecture-by-prefecture analysis, calculation of the maximum-minimum ratio of RT facilities per million population and per 30km2 revealed a disparity of 3.7 and 73.1 times in the population ratio and the density ratio, respectively. Although a correlation was found between the number of TPSs per RT device or the number of medical physicists per million population and the rate of high-precision RT implementation, no correlation was found among other professions. Detailed analysis based on the hospital size and prefecture provided more specific information on the medical functions of RT facilities in Japan. These findings can potentially contribute to the future development of RT, including the standardization of treatment techniques and optimal resource allocation.

Activity concentration of NORM at reclaimed ex-coal mines in South Sumatra, Indonesia

Unbeknownst to us, natural radiation is in close proximity to human existence. Post-mining practices can generate naturally occurring radionuclides that have the potential to cause radiological effects on human health. This study utilized soil samples obtained from ex-mining reclamation land in Banko Barat, South Sumatra Province, to assess the concentration of natural radioactivity and the corresponding radiation dose. Eight composite soil samples were collected from reclaimed land. The samples underwent processing and analysis through gamma spectrometry in order to ascertain the activity concentration of the radionuclides 226Ra, 232Th, and 40K. The RESRAD-ONSITE 7.2 software utilizes the activity concentration of soil samples as an input parameter to accurately predict the dose rate for workers. The projected dose rate was determined by considering four routes of exposure: external gamma radiation, inhalation, radon, and ingestion of soil. The measured activity values of soil samples from reclamation land for 226Ra ranged from 25.6704 ± 0.5082 to 58.8555 ± 0.6917 Bq/kg. The activity values for 232Th ranged from 30.5546 ± 0.1757 to 42.53020.3004 Bq/kg. Lastly, the activity values for 40K ranged from 533.902 ± 6.4023 to 988.081 ± 9.6948 Bq/kg. The total effective dose rate measured in the reclaimed land falls between 0.08673 and 0.1469 millisieverts per year. The value does not surpass the maximum limit set by BAPETEN, which is one mSv/year. Therefore, no additional protective measures are required for workers.

Granulomatous Slack Skin With Lung and Esophagus Involvement: A Case Report and Molecular Analysis.

Granulomatous slack skin (GSS) is a rare subtype of mycosis fungoides, and few cases have been known to spread to the blood, lymph nodes, or viscera. We present a case with early dissemination to the lung. A 27-year-old woman, previously healthy, presented with scattered disseminated scaly patches, associated with vulvar and intergluteal firm swelling and groin-skin induration for 1 year. She also reported mild fatigue and breathlessness on moderate exertion. The patient underwent blood tests, skin biopsies, and computed tomography scan. The skin biopsy showed a mildly atypical T-cell lymphoid infiltrate involving the dermis/hypodermis, with focal epidermotropism, associated with a granulomatous infiltrate and elastophagocytosis. The computed tomography scan revealed bilateral ground-glass lung nodular opacities. Positron emission tomography showed an increased signal in the skin and subcutis around the buttocks, inguinal and mediastinal lymph nodes, and lungs. The lung biopsy confirmed a dense T-cell infiltrate with numerous multinucleated giant cells. Subsequently, esophageal involvement was also observed following biopsy. Molecular analyses demonstrated identical T-cell clones in the skin and lung. After 6 cycles of chemotherapy/localized external radiotherapy, the patient had a partial skin response and stable lung disease. A preferred diagnosis of GSS with systemic spread was made based on clinical/histologic/molecular findings, after considering granulomatous mycosis fungoides and peripheral T-cell lymphoma, not otherwise specified. This case highlights the frequent diagnostic difficulty in distinguishing GSS from an inflammatory granulomatous dermatitis. Pulmonary and esophageal involvements are rare in GSS, and the simultaneous presentation of characteristic cutaneous GSS with systemic disease poses an additional classification challenge.