Radiation In Region Research Articles

Non-steroidal anti-inflammatory drugs (NSAIDs) in cancer pain: A database analysis to determine recruitment feasibility for a clinical trial

Background: Insufficient evidence exists to support or refute use of NSAIDs for managing cancer pain. Palliative physicians support a placebo-controlled trial of NSAIDs as strong opioid adjuncts for cancer-induced bone pain as the most pragmatic design to benefit clinical practice. Aim: We aimed to determine patient numbers receiving palliative radiotherapy for cancer-induced bone pain, estimate the suitability of NSAID prescription and determine survival, guiding future trial feasibility. Design: A retrospective observational database analysis was undertaken using 5 years of routinely collected regional radiotherapy and healthcare data, filtered to achieve a cohort with cancer-induced bone pain. Demographics and survival were linked to available serology and co-morbidity data. Setting/participants: Data was sourced from the regional Leeds Cancer Centre, a tertiary care setting. Patients who underwent palliative single fraction 8 gray (Gy) radiotherapy treatment for cancer-induced bone pain were included, totalling 2411 over 5 years. Results: A mean of 478 patients received palliative radiotherapy for cancer-induced bone pain annually. Median age (IQR) was 70 (62–77); negatively skewed (−0.69). 65.3% died within 1 year of radiotherapy; 48.0% within 6 months. Age was not associated with survival on univariable analysis (HR 0.999 (95% CI 0.996–1.003)). Serology from 1063 patients (44.2%) were available; eGFR was ⩾60 mL/min/1.73 m2 in 83.0%. From available data (1352 pts; 51.6% of sample), 20.2% had a coded co-morbidity contra-indicating NSAIDs. Combining serology and co-morbidities, 68.5% could be considered for NSAID prescription. Conclusions: Patient numbers at a regional radiotherapy centre support the feasibility of trial recruitment. Available serology and co-morbidity data suggest two-thirds may be suitable for NSAID prescription.

Optical Soldering of MoS2 Layers for Defect Structure Formation with Induced Photoluminescence

AbstractLocal manipulation of the defect structures in 2D semiconducting transition metal dichalcogenide (2D TMD) opens rich research avenues harnessing their unique optoelectronic properties, where reliable defect structure formation methods are highly desirable. Here, the concept of optical soldering (OS) on few‐layer MoS2 to form site‐selective defect structures with induced photoluminescence (PL) is proposed and demonstrated. OS is initiated by optical heating of the top MoS2 layer to elevate the local temperature above the melting point of the underlying indium‐tin‐oxide nanoparticles (ITO‐NPs). In turn, thermally deformed ITO‐NPs pull the top MoS2 layer down to the substrate, forming the OS‐induced defect structure on the optically irradiated region. The OS‐induced defect structures on a few‐layer MoS2 show bright PL, which can be manipulated in peak positions by varying the incident optical power and irradiation time. OS is a facile method for local defect structure patterning on few‐layer MoS2 and manipulation of their optoelectronic properties while requiring low incidence optical power (≈2.5 mW) and fast process time (≈1 s), which are beneficial in the development of 2D TMD material‐based applications.

7: Rates of Regional Radiotherapy Receipt Over Time in Low-Risk, Node Positive Breast Cancer

7: Rates of Regional Radiotherapy Receipt Over Time in Low-Risk, Node Positive Breast Cancer

Nanoindentation experiment and crystal plasticity study on the mechanical behavior of Fe-ion-irradiated A508-3 steel

This study investigates the mechanical properties of A508-3 steel irradiated with Fe ions to 0.1, 0.4, 2.0, and 5.0 dpa at 20, 100, and 300 °C using a nanoindentation experiment and crystal plasticity finite element model (CPFEM). The Nix–Gao model is applied to obtain the hardness H0 based on the measured data. The hardness of the steel increases with increasing radiation damage at all temperatures. The simulations of the nanoindentation process by CPFEM loaded in the [001], [110], [111], [112], and [123] directions concurred with the corresponding experimental data in all the studied cases, validating the CPFEM results. The dislocation loop expedites the increase of mobile dislocation and retards the decrease of immobile dislocation, resulting in larger von Mises stresses of the irradiated samples with a flatter shape, especially near the irradiated region. Furthermore, the area of the von Mises stress shrinks with an increase in temperature. This study could help understand the macroscopic deformation behavior of irradiated steel based on experimental and microstructural analyses.

Site-selective low-temperature growth of Au nanowires on Si substrates irradiated with low-energy Ar ions

We demonstrated the site-selective growth of freestanding single-crystalline Au NWs at a low temperature (approximately 573 K) by pretreating a silicon substrate with low-energy ion beams, followed by thermal evaporation of Au. Using this method, Au NWs with aspect ratios up to 1000 or more, that is, 50–200 nm in diameter and lengths ranging from several hundred nanometers to approximately 100 μm, were fabricated. Au NWs could only be grown at the boundary between the ion-irradiated and unirradiated regions on the Si substrates during the deposition of Au. Furthermore, patterning the Si substrate by masking it with a fine mesh during ion irradiation creates more boundaries between the irradiated and unirradiated regions, increasing the number of Au NWs. Transmission electron microscopy and selected-area electron diffraction revealed that the NWs were single crystals and grew along the [110] direction.

Kinetic regularities of the formation of composite electrolytic coatings containing ultradispersed diamond particles

The paper formulates the problem of joint electrolytic co-deposition of metal ions and ultradispersed diamond particles into a metal matrix. It presents the developed mathematical model that describes the mechanism and kinetics of the cathode process, mass transfer of metal ions and ultradispersed diamond particles. A satisfactory correlation with experimental data was obtained. The contribution of the thermal action of laser radiation to the intensification of the process of co-deposition of dispersed particles and metal ions was determined. It was found that the more intense penetration of dispersed phase particles into the forming coating during the laser stimulation of the electrodeposition process is due to the presence of a temperature gradient, which provides an additional supply of metal ions in the irradiation region. Based on the theoretical and experimental studies, we established the regularities of the influence of the number and size of nanoparticles on the strengthening properties of composite metal coatings. It was found that an increase in the temperature of an aqueous electrolyte solution in the cathode region during a laser-stimulated deposition process leads to an increase in the flux density of ultradispersed diamond particles, and, as a result, to an increase in the concentration of the dispersed phase in nickel composite coatings, which contributes to the formation of a finer crystalline structure of coatings, an improvement in adhesion, strength properties and increased wear resistance of coatings.

A New Model for Predicting Nonsentinel Lymph Node Metastasis in Early-Stage Breast Cancer Using MMP15.

Background In early-stage breast cancer (BC) patients, 40–70% of lymph node metastases are limited to the sentinel lymph nodes (SLNs). Patients at low risk for nonsentinel lymph node (NSLN) metastasis should be exempt from axillary lymph node dissection (ALND) or regional lymph node radiotherapy (RNI). Methods The present study included 237 female early-stage BC patients with positive SLNs who received ALND. Based on the clinicopathological factors of the 158 patients in the training cohort, multivariate analysis was used to determine the independent risk factors for NSLN metastasis, which were used to establish the NSLN metastasis prediction model. The calibration and discrimination of this model were tested with the training and validation cohorts and compared to the Memorial Sloan Kettering Cancer Center (MSKCC) model. Results Tumor size, neural invasion, lymphovascular invasion, expression of matrix metalloproteinase 15 (MMP15) in the cytoplasm, and the number of positive SLNs were statistically significant by multivariate analysis (P < 0.05), which were used to establish the new model. The MSKCC model was verified by the training cohort, and the area under the receiver-operating characteristic (ROC) curve was 0.733 (95% CI: 0.650–0.816), which was less than that of the new model (0.824; 95% CI: 0.760–0.889). The area under the ROC curve in the validation cohort for the new model was 0.773 (95% CI: 0.669–0.877), and the calibration performed well. The false-negative rates were 3.2%, 6.5%, and 14.5% for the predicted probability cut-offs of 50%, 60%, and 70%, respectively. Conclusions The new model included five variables: tumor size, neural invasion, lymphovascular invasion, cytoplasmic MMP15 expression, and the number of positive SLNs. The model with a cut-off of 60% could accurately identify low-risk patients with NSLN metastasis.

Spatial Gene Expression Changes in the Mouse Heart After Base-Targeted Irradiation

Radiation cardiotoxicity (RC) is a clinically significant adverse effect of treatment for patients with thoracic malignancies. Clinical studies in lung cancer have indicated that heart substructures are not uniformly radiosensitive, and that dose to the heart base drives RC. In this study, we aimed to characterize late changes in gene expression using spatial transcriptomics in a mouse model of base regional radiosensitivity. An aged female C57BL/6 mouse was irradiated with 16 Gy delivered to the cranial third of the heart using a 6×9 mm parallel opposed beam geometry on a small animal radiation research platform, and a second mouse was sham-irradiated. After echocardiography, whole hearts were collected at 30 weeks for spatial transcriptomic analysis to map gene expression changes occurring in different regions of the partially irradiated heart. Cardiac regions were manually annotated on the capture slides and the gene expression profiles compared across different regions. Ejection fraction was reduced at 30 weeks after a 16 Gy irradiation to the heart base, compared with the sham-irradiated controls. There were markedly more significant gene expression changes within the irradiated regions compared with nonirradiated regions. Variation was observed in the transcriptomic effects of radiation on different cardiac base structures (eg, between the right atrium [n=86 dysregulated genes], left atrium [n=96 dysregulated genes], and the vasculature [n=129 dysregulated genes]). Disrupted biological processes spanned extracellular matrix as well as circulatory, neuronal, and contractility activities. This is the first study to report spatially resolved gene expression changes in irradiated tissues. Examination of the regional radiation response in the heart can help to further our understanding of the cardiac base's radiosensitivity and support the development of actionable targets for pharmacologic intervention and biologically relevant dose constraints.

Self-powered waveguide-integrated photodetector based on a defect-engineered WSe2/graphene heterojunction

With integration capability and excellent photoelectronic, two-dimensional materials have attracted increasing interest in photonic circuits as waveguide-integrated photodetectors. Here, we report a waveguide-integrated self-powered photodetector based on a defect-engineered WSe2/graphene (WSe2/G) heterostructure. The WSe2 side of the heterostructure is locally irradiated by the Ga+ ion beam generating S-vacancies (WSe2-0.18/G). The boundary of the irradiated and non-irradiated regions (WSe2/G-WS2-0.18/G) construct a Schottky-metal junction with the photovoltaic property. This WSe2/G-WS2-0.18/G heterostructure exhibits a broad spectral photoresponse from 450 nm to 1550 nm at 0 bias with on/off ratio of 104. As a self-powered photodetector, WSe2/G-WS2-0.18/G heterostructure is integrated with a polymer waveguide. It directly reads optical signal (100 kHz @ 1550 nm) in the waveguide. Our work paves a novel avenue to prepare the self-powered 2D photodetector for integration with photonic circuits.

EP-276 Tall Cell Carcinoma with Reverse Polarity (TCCRP) of the breast; a rare form of breast cancer

Abstract Aim A case report on the diagnosis and treatment of this rare low grade triple negative breast cancer. Case Report A 41 year old female presented with a palpable left breast lump. Family history includes a sister with a rare myeloproliferative disorder. On examination, a left breast lower outer quadrant 2–3 cm hard irregular lump was palpable. Mammography and ultrasound revealed a 25 mm suspicious lesion (which was biopsied), with normal appearing lymph nodes. Results Biopsy revealed a grade 2 invasive apocrine carcinoma. Oestrogen and Herceptin receptors negative. Breast conserving surgery with sentinel lymph node biopsy was performed. Histology revealed a 22 mm well circumscribed tumour with nests of epithelial cells in micropapillary pattern with apocrine like appearance. The most striking feature was that the nuclei were at the apical rather than the basal poles of the epithelial cells (reverse polarity). No lymphovascular invasion present. Lymph nodes were negative (0/3). Diagnosis was then confirmed by molecular testing. Conclusion Tall cell carcinoma with reverse polarity (TCCRP)1, a rare cancer resembling tall cell variant of papillary thyroid carcinoma, was first reported by Eusebi et al in 20032. Although morphologically similar to metastatic papillary thyroid cancer, neither the immunohistochemical markers nor genetic profiles have established any connection3. Accurate diagnosis of TCCRP is important as it carries an excellent prognosis. Treatment is local regional radiotherapy. There is no indication for systemic therapy in this case, due to its indolent low metastatic potential.

De-escalation of radiotherapy after primary chemotherapy in cT1–2N1 breast cancer (RAPCHEM; BOOG 2010–03): 5-year follow-up results of a Dutch, prospective, registry study

Primary chemotherapy in breast cancer poses a dilemma with regard to adjuvant locoregional radiotherapy, as guidelines for locoregional radiotherapy were originally based on pathology results of primary surgery. We aimed to evaluate the oncological safety of de-escalated locoregional radiotherapy in patients with cT1-2N1 breast cancer treated with primary chemotherapy, according to a predefined, consensus-based study guideline. In this prospective registry study (RAPCHEM, BOOG 2010-03), patients referred to one of 17 participating radiation oncology centres in the Netherlands between Jan 1, 2011, and Jan 1, 2015, with cT1-2N1 breast cancer (one to three suspicious nodes on imaging before primary chemotherapy, of which at least one had been pathologically confirmed), and who were treated with primary chemotherapy and surgery of the breast and axilla were included in the study. The study guideline comprised three risk groups for locoregional recurrence, with corresponding locoregional radiotherapy recommendations: no chest wall radiotherapy and no regional radiotherapy in the low-risk group, only local radiotherapy in the intermediate-risk group, and locoregional radiotherapy in the high-risk group. Radiotherapy consisted of a biologically equivalent dose of 25 fractions of 2 Gy, with or without a boost. During the study period, the generally applied radiotherapy technique in the Netherlands was forward-planned or inverse-planned intensity modulated radiotherapy. 5-year follow-up was assessed, taking into account adherence to the study guideline, with locoregional recurrence rate as primary endpoint. We hypothesised that 5-year locoregional recurrence rate would be less than 4% (upper-limit 95% CI 7·8%). This study was registered at ClinicalTrials.gov, NCT01279304, and is completed. 838 patients were eligible for 5-year follow-up analyses: 291 in the low-risk group, 370 in the intermediate-risk group, and 177 in the high-risk group. The 5-year locoregional recurrence rate in all patients was 2·2% (95% CI 1·4-3·4). The 5-year locoregional recurrence rate was 2·1% (0·9-4·3) in the low-risk group, 2·2% (1·0-4·1) in the intermediate-risk group, and 2·3% (0·8-5·5) in the high-risk group. If the study guideline was followed, the locoregional recurrence rate was 2·3% (0·8-5·3) for the low-risk group, 1·0% (0·2-3·4) for the intermediate-risk group, and 1·4% (0·3-4·5) for the high-risk group. In this study, the 5-year locoregional recurrence rate was less than 4%, which supports our hypothesis that it is oncologically safe to de-escalate locoregional radiotherapy based on locoregional recurrence risk, in selected patients with cT1-2N1 breast cancer treated with primary chemotherapy, according to this predefined, consensus-based study guideline. Dutch Cancer Society. For the Dutch translation of the abstract see Supplementary Materials section.

Effect of native carbon vacancies on evolution of defects in ZrC1- under He ion irradiation and annealing

The dynamic study of radiation-induced defects with annealing is critical for the material design for next-generation nuclear energy systems. The native vacancy could affect the development of defects, which lacks study. In the present work, the as-hot pressed ZrC1-x (x=0, 0.15, 0.3) ceramics which comprised crystallites of a few microns in size with different amounts of carbon vacancies were irradiated by 540 keV He2+ ions at room temperature with a fluence of 1 × 1017/cm2. The radiation-induced lattice expansion was found to be a common phenomenon in a sequence of ZrC0.85≥ZrC1.0>ZrC0.7. Both X-ray and electron diffractions confirmed maintenance of structural integrity without amorphization after irradiation. Inside the irradiated region, only “black-dot” type defects, i.e., clusters of point defects were observed while no helium-induced cavities, cracks, or extended dislocations were detected. The as-irradiated ZrC1-x were then annealed at different high temperatures. Upon annealing at 800 °C, very tiny helium-induced cavities were found to be generated and the crystal lattice recovered to a great extent, especially for the sub-stoichiometric samples. While annealed at 1500 °C, all the samples almost fully recovered the crystal lattices close to those of as-hot pressed ones. Meanwhile, large cavities and extended dislocations were generated. With increasing amount of native carbon vacancies, the size of cavities increased while the length and density of extended dislocations decreased. Inverse changes of lattice parameters during irradiation and annealing processes have been interpreted by the kinetics of defects. Finally, the correlation between native vacancies and damage behavior is discussed.

Measuring Indirect Radiation-Induced Perfusion Change in Fed Vasculature Using Dynamic Contrast CT.

Recent functional lung imaging studies have presented evidence of an “indirect effect” on perfusion damage, where regions that are unirradiated or lowly irradiated but that are supplied by highly irradiated regions observe perfusion damage post-radiation therapy (RT). The purpose of this work was to investigate this effect using a contrast-enhanced dynamic CT protocol to measure perfusion change in five novel swine subjects. A cohort of five Wisconsin Miniature Swine (WMS) were given a research course of 60 Gy in five fractions delivered locally to a vessel in the lung using an Accuray Radixact tomotherapy system with Synchrony motion tracking to increase delivery accuracy. Imaging was performed prior to delivering RT and 3 months post-RT to yield a 28–36 frame image series showing contrast flowing in and out of the vasculature. Using MIM software, contours were placed in six vessels on each animal to yield a contrast flow curve for each vessel. The contours were placed as follows: one at the point of max dose, one low-irradiated (5–20 Gy) branching from the max dose vessel, one low-irradiated (5–20 Gy) not branching from the max dose vessel, one unirradiated (<5 Gy) branching from the max dose vessel, one unirradiated (<5 Gy) not branching from the max dose vessel, and one in the contralateral lung. Seven measurements (baseline-to-baseline time and difference, slope up and down, max rise and value, and area under the curve) were acquired for each vessel’s contrast flow curve in each subject. Paired Student t-tests showed statistically significant (p < 0.05) reductions in the area under the curve in the max dose, and both fed contours indicating an overall reduction in contrast in these regions. Additionally, there were statistically significant reductions observed when comparing pre- and post-RT in slope up and down in the max dose, low-dose fed, and no-dose fed contours but not the low-dose not-fed, no-dose not-fed, or contralateral contours. These findings suggest an indirect damage effect where irradiation of the vasculature causes a reduction in perfusion in irradiated regions as well as regions fed by the irradiated vasculature.

TEM characterization of irradiation-induced dislocation loops and voids in ion-irradiated pure chromium

Chromium (Cr) based coatings have been proposed for Zircaloy fuel rods to enhance the accident tolerance in water-cooled reactors. However, the response of Cr to irradiation has received limited attention in prior studies. To get a better understanding of radiation damage in Cr for future nuclear applications, in the present study, the irradiation-induced microstructure evolution of dislocation loops and voids was studied in pure Cr subjected to 2.8 MeV iron ions irradiation at 550 °C (belonging to stage III, intermediate-temperature). TEM observation results show that the distribution of dislocation loops extends the SRIM simulated irradiation depth to 3.5 µm, while voids were only formed in the irradiated region up to a depth of 1.3 µm. A rigorous method with combined consideration of edge-on view and inside-outside analysis was proposed to determine the habit plane. With this method, what has normally considered as an unsafe zone becomes a favored zone for determining the nature of dislocation loops. The nature of dislocation loops was determined including both interstitial and vacancy types with ½<111> Burgers vector in all regions. Within the irradiation region, the loops are approaching half interstitial and half vacancy, while beyond the irradiated region interstitial loops became dominant. The irradiation-induced swelling was quantified by the void size and density. The swellings are mostly corresponding well with the irradiation dose distribution which is simulated by SRIM. The swelling rate close to the peak region is around 0.3%/dpa. Results demonstrate that Cr tends to experience some similarities in irradiation loop evolution to W-based, Mo-based materials, as they are in the same group in the periodic table, despite the discrepancy in the characteristic of loops such as the irradiation temperature-dependent dislocation loop formation was observed as well. The present study is significant not only for supplementing the fundamental knowledge of irradiation damage in Cr but also for the application of Cr coating to the accident tolerant fuel claddings or other nuclear structure materials.

Investigation on laser forming of open cell aluminum foam

Open cell aluminum foam having high porosity has the potential to increase the efficiency of a heat exchanger and also to be used for diverse other functions. However, being prone to fail easily under tensile mechanical load, their thermal forming using a laser has been proposed in the literature. This work investigates the effect of laser parameters, orientation-position-curvature of scan path, the number of scans, and foam thickness on the bending angle achieved while forming 95% porous pure aluminum (99.7% aluminum) open cell foam plates using a diode laser. Furthermore, the capability of laser forming to produce developable and nondevelopable surfaces out of this foam has been demonstrated. Higher line energy gave a higher bending angle. Under the same line energy, the combination of higher power-higher scan speed produced a higher bending angle. In contradiction to laser forming of the sheet metal, no saturation or reduction in bending angle per scan pass was observed with an increase in scan pass number. This observation could be explained with the help of cell densification by previous scan passes leading to an increase in the coupling of more thermal energy for subsequent scan passes. Scan paths with increased curvature (or less radius) also produced higher bending due to a higher amount of cell collapse in the irradiated region.

Prediction of breast cancer-related lymphedema by dermal backflow detected with near-infrared fluorescence lymphatic imaging

PurposeMild breast cancer-related lymphedema (BCRL) is clinically diagnosed as a 5%–10% increase in arm volume, typically measured no earlier than 3–6 months after locoregional treatment. Early BCRL treatment is associated with better outcomes, yet amid increasing evidence that lymphedema exists in a latent form, treatment is typically delayed until arm swelling is obvious. In this study, we investigated whether near-infrared fluorescence lymphatic imaging (NIRF-LI) surveillance could characterize early onset of peripheral lymphatic dysfunction as a predictor of BCRL.MethodsIn a prospective, longitudinal cohort/observational study (NCT02949726), subjects with locally advanced breast cancer who received axillary lymph node dissection and regional nodal radiotherapy (RT) were followed serially, between 2016 and 2021, before surgery, 4–8 weeks after surgery, and 6, 12, and 18 months after RT. Arm volume was measured by perometry, and lymphatic (dys) function was assessed by NIRF-LI.ResultsBy 18 months after RT, 30 of 42 study subjects (71%) developed mild–moderate BCRL (i.e., ≥ 5% arm swelling relative to baseline), all manifested by “dermal backflow” of lymph into lymphatic capillaries or interstitial spaces. Dermal backflow had an 83% positive predictive value and 86% negative predictive value for BCRL, with a sensitivity of 97%, specificity of 50%, accuracy of 83%, positive likelihood ratio of 1.93, negative likelihood ratio of 0.07, and odds ratio of 29.00. Dermal backflow appeared on average 8.3 months, but up to 23 months, before the onset of mild BCRL.ConclusionBCRL can be predicted by dermal backflow, which often appears months before arm swelling, enabling early treatment before the onset of edema and irreversible tissue changes.

Assessment of Tissue Oxygenation and Radiation Dermatitis Pre-, During, and Post-Radiation Therapy in Breast Cancer Patients.

Over 95% of breast cancer patients treated with radiation therapy (RT) undergo an adverse skin reaction known as radiation dermatitis (RD). Assessment of severity or grading of RD is clinically visual and hence subjective. Our objective is to determine sub-clinical tissue oxygenation (oxygen saturation) changes in response to RT in breast cancer patients using near-infrared spectroscopic imaging and correlate these changes to RD grading. A 4-8 week longitudinal pilot imaging study was carried out on 10 RT-treated breast cancer patients. Non-contact near-infrared spectroscopic (NIRS) imaging was performed on the irradiated ipsilateral and the contralateral breast/chest wall, axilla and lower neck regions before RT, across the weeks of RT, and during follow-up after RT ended. Significant changes (p < 0.05) in oxygen saturation (StO2) of irradiated and contralateral breast/chest wall and axilla regions were observed across weeks of RT. The overall drop in StO2 was negatively correlated to RD scaling (in 7 out of 9 cases) and was higher in the irradiated regions when compared to its contralateral region. Differences in the pre-RT StO2 between ipsilateral and contralateral chest wall is a potential predictor of the severity of RD. The subclinical recovery of StO2 to its original state was longer than the visual recovery in RD grading scale, as observed from the post-RT assessment of tissue oxygenation.

Histopathological Examination of an Explanted Heart in a Long-Term Responder to Cardiac Stereotactic Body Radiotherapy (STereotactic Arrhythmia Radioablation).

Cardiac stereotactic body radiotherapy is an emerging treatment method for recurrent ventricular tachycardia refractory to invasive treatment methods. The single-fraction delivery of 25 Gy was assumed to produce fibrosis, similar to a post-radiofrequency ablation scar. However, the dynamics of clinical response and recent preclinical findings suggest a possible different mechanism. The data on histopathological presentation of post-radiotherapy hearts is scarce, and the authors provide significantly different conclusions. In this article, we present unique data on histopathological examination of a heart explanted from a patient who had a persistent anti-arrhythmic response that lasted almost a year, until a heart failure exacerbation caused a necessity of a heart transplant. Despite a complete treatment response, there was no homogenous transmural fibrosis in the irradiated region, and the overall presentation of the heart was similar to other transplanted hearts of patients with advanced heart failure. In conclusion, our findings support the theorem of functional changes as a source of the anti-arrhythmic mechanism of radiotherapy and show that durable treatment response can be achieved in absence of transmural fibrosis of the irradiated myocardium.

Electronic energy loss and ion velocity correlation effects in track production in swift-ion-irradiated LiNbO3: A quantitative assessment between structural damage morphology and energy deposition

• Essential factors including electronic energy loss and ion velocity co-affect latent track damage. • Damage morphologies from spherical defects to discontinuous and continuous tracks are confirmed. • Atomic energy deposition and temperature evolution are determined by inelastic thermal spike model. • A quantitative relationship between ion irradiation condition and track damage response is proposed. • The work provides a deeper insight for understanding ion-solid interactions and damage behaviors. The primary motivation for studying how irradiation modifies the structures and properties of solid materials involves the understanding of undesirable phenomena, including irradiation-induced degradation of components in nuclear reactors and space exploration, and beneficial applications, including material performance tailoring through ion beam modification and defect engineering. In this work, the formation mechanism of latent tracks with different damage morphologies in LiNbO 3 crystals under 0.09–6.17 MeV/u ion irradiation with an electronic energy loss from 2.6–13.2 keV/nm is analyzed by experimental characterizations and numerical calculations. Irradiation-induced damage is preliminarily evaluated via the prism coupling technique to analyze the correlation between the dark-mode spectra and energy loss profiles of irradiated regions. Under the irradiation conditions of different ion velocities and electronic energy losses, different damage morphologies, from individual spherical defects to discontinuous and continuous tracks, are experimentally characterized. During ion penetration process, the ion velocity determines the spatiotemporal distribution of deposited irradiation energy induced by electronic energy loss, meaning that the two essential factors including electronic energy loss and ion velocity co-affect the track damage. The inelastic thermal spike model is used to numerically calculate the spatiotemporal evolutions of energy deposition and the corresponding atomic temperature under different irradiation conditions, and a quantitative relationship is proposed by comparison with corresponding experimentally observed track damage morphologies. The obtained quantitative relationship between irradiation conditions and track damage provides deep insight and guidance for understanding the damage behavior of crystal materials in extreme radiation environments and selecting irradiation parameters, including ion species and energies, for ion beam technique application in atomic-level defect manipulation, material modification, and micro/nanofabrication.

4D dual-mode staring hyperspectral-depth imager for simultaneous spectral sensing and surface shape measurement.

A 4D dual-mode staring hyperspectral-depth imager (DSHI), which acquire reflectance spectra, fluorescence spectra, and 3D structural information by combining a staring hyperspectral scanner and a binocular line laser stereo vision system, is introduced. A 405 nm laser line generated by a focal laser line generation module is used for both fluorescence excitation and binocular stereo matching of the irradiated line region. Under the configuration, the two kinds of hyperspectral data collected by the hyperspectral scanner can be merged into the corresponding points in the 3D model, forming a dual-mode 4D model. The DSHI shows excellent performance with spectral resolution of 3 nm, depth accuracy of 26.2 µm. Sample experiments on a fluorescent figurine, real and plastic sunflowers and a clam are presented to demonstrate system's with potential within a broad range of applications such as, e.g., digital documentation, plant phenotyping, and biological analysis.