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Boron neutron capture therapy (BNCT) is a physiologically focused radiation therapy that relies on nuclear capture and fission processes. BNCT is regarded as one of the most promising treatments due to its excellent accuracy, short duration of therapy, and low side effects. The creation of novel boron medicines with high selectivity, ease of delivery, and high boron‐effective load is a current research topic. Herein, boron‐containing carbon dots (BCDs) and their human serum albumin (HSA) complexes (BCDs‐HSA) are designed and synthesized as boron‐containing drugs for BNCT. BCDs (10B: 7.1 wt%) and BCDs‐HSA exhibited excitation‐independent orange fluorescent emission which supported the use of fluorescence imaging for tracking 10B in vivo. The introduction of HSA enabled BCDs‐HSA to exhibit good biocompatibility and increased tumor accumulation. The active and passive targeting abilities of BCDs‐HSA are explored in detail. Subcutaneous RM‐1 tumors and B16‐F10 tumors both significantly decrease with BNCT, which consists of injecting BCDs‐HSA and then irradiating the area with neutrons. In short, this study provides a novel strategy for the delivery of boron and may broaden the perspectives for the design of boron‐containing carbon dots nanomedicine for BNCT. [ABSTRACT FROM AUTHOR]

Scientists in Nazi Germany attempted but failed to build an atomic bomb or working nuclear reactor during the years of the Second World War, 1939-1945. Can philosophical meaning be drawn from this history? The history of the Nazi scientists and nuclear fission raises important issues concerning the alleged value-neutrality of scientific research and technological development. We can also ask whether there is an ethical dimension to the failure of the Nazi bomb project. Did the scientists who worked in the Third Reich make a moral decision not to complete the development of a working nuclear reactor and/or a usable nuclear explosive device? In this essay, I argue that Werner Heisenberg and other Nazi scientists fell victim to a value-neutral conception of science that led them to make unethical choices in support of the Nazi regime. The story of the Nazi bomb project exemplifies a more general philosophical point: if scientists fail to understand the social, political, and cultural context of their research they will be vulnerable to ethically wrong decisions. [ABSTRACT FROM AUTHOR]

Atmospheric traces of radioactive xenon can be a strong indicator for underground nuclear fission reactions. 131mXe, 133Xe, 133mXe and 135Xe are the primary gaseous isotopes/isomers currently used to identify and classify nuclear events. During decay, each of these radioactive species produces a unique beta-gamma energy spectra, which can be measured using beta-gamma coincidence counting. Current operational Xe beta-gamma spectrum analysis software relies on Region of Interest (ROI) counting (Bowyer et al. in J Environ Radioact 59(2):139–151, 2002). This algorithm occasionally produces mismeasurements, especially when quantifying meta-stable isomers, due to overlapping ROIs and shifts in detector calibration in fielded systems over time (Ringbom and Axelsson in Appl Radiat Isot 156:108950, 2020). In an attempt to better de-convolve overlapping isotope spectra we have developed a technique that applies a supervised neural-network implemented in TensorFlow with Keras to classify and quantify the isotopes and mixtures of isomers based on their beta-gamma spectra—similar to image recognition. From this, we have improved upon the false-positive rate for classification and regression models, however challenges remain with dealing with differing detector energy calibrations and with estimating measurement uncertainty. [ABSTRACT FROM AUTHOR]

The article discusses the challenges and delays in achieving commercial nuclear fusion as a viable energy source, despite optimistic projections in the past. Various experts highlight the technical difficulties in containing high-energy neutrons released during the fusion process and the scarcity of tritium fuel needed for fusion reactors. Governments and private investors continue to fund fusion research for scientific understanding, technological advancements, and potential military applications, although the commercialization of fusion energy remains uncertain. The article also explores China's significant investment in fusion research and the motivations behind private sector investments in this field. [Extracted from the article]

The incidence and prevalence of breast cancer in Iraq are alarming. Breast cancer is one of the most common cancers among Iraqi women, and its rates have been steadily increasing over the years. The exact reasons for the high incidence are not yet fully understood, but it is believed to be influenced by a combination of genetic, environmental, and lifestyle factors. The research objectives of this study revolve around two main goals. Firstly, the study aims to establish baseline values for the amount of uranium present in blood samples. Secondly, the study aims to assess the potential relationship between uranium levels in blood and the development of cancer. The investigation includes 16 blood samples from women diagnosed with breast cancer and 20 blood samples from women without breast cancer. The nuclear fission track analysis method using CR-39 solid-state nuclear track detectors will be employed to analyze the uranium contents in women's cancer blood (CB) samples. The methodology adopted for this study involved utilizing the SPSS program to conduct a comprehensive statistical analysis. The results of the study indicate that there is a variation in uranium concentration among both the patient women and healthy women. The uranium concentration among patient women ranged from 3.259 ppb to 1.918 ppb, while among healthy women, it varied from 2.105 ppb to 0.59 ppb. These findings suggest that there may be a correlation between the presence of certain health issues and higher uranium levels. [ABSTRACT FROM AUTHOR]

Materials applied in nuclear environments such as fission or fusion power-plants face severe conditions. The irradiation by neutrons induces thermal loads and irradiation damage. Furthermore, coolants in contact with the materials induce corrosion, which is particularly challenging for liquid salts intended for the next generation of fission reactors. A new device (DICE) is installed at the 3.5 MV accelerator at DIFFER for the accelerated testing of such materials under combined irradiation and corrosion conditions. The DICE enables irradiation of samples at temperatures of up to 1050 K and in contact with liquid salts. An integrated shielding and a low power temperature control concept based on radiation cooling enables high-duty cycle application in a standard accelerator laboratory. Ion currents of up to 30 µA are possible with continuous irradiation. This work outlines the technical concept of the device and presents the first data. [ABSTRACT FROM AUTHOR]

The correlation between the variations of multiplicity of prompt fission neutrons and the total kinetic energy of fission fragments was studied using a double ionization chamber in combination with a prompt fission neutron detector. An estimate was made of the systematic errors introduced by crosstalk caused by the multi-module structure of the neutron detector. [ABSTRACT FROM AUTHOR]

There are profound connections between neutrino physics and nuclear experiments. Exceptionally precise measurements of single and double beta-decay spectra illuminate the scale and nature of neutrino mass and may finally answer the question of whether neutrinos are their own anti-matter counterparts. Neutrino–nucleus scattering underpins oscillation experiments and probes nuclear structure, neutrinos offer a rare vantage point into collapsing stars and nuclear fission reactors and techniques pioneered in neutrino nuclear physics experiments are advancing quantum sensing technologies. In this article, we review current and planned efforts at the intersection of neutrino and nuclear experiments. This article is part of the theme issue 'The liminal position of Nuclear Physics: from hadrons to neutron stars'. [ABSTRACT FROM AUTHOR]

Although the principal physical behaviour of a material is inherently connected to its fundamental crystal structure, the behaviours observed in the real-world are often driven by the microstructure, which for many polycrystalline materials, equates to the size and shape of the constituent crystal grains. Here we highlight a cutting edge synthesis route to the controlled engineering of grain structures in thin films and the simplification of associated 3-dimensional problems to less complex 2D ones. This has been applied to the actinide ceramic, uranium dioxide, to replicate structures typical in nuclear fission fuel pellets, in order to investigate the oxidation and subsequent transformation of cubic UO2 to orthorhombic U3O8. This article shows how this synthesis approach could be utilised to investigate a range of phenomena, affected by grain morphology, and highlights some unusual results in the oxidation behaviour of UO2, regarding the phase transition to U3O8. [ABSTRACT FROM AUTHOR]

The propagation of online rumors is rapid, and its propagation mechanism has always been a research difficulty. In this paper, the network rumors are compared to the nuclear fission process, and a network rumors propagation model is constructed. First, the initial online rumors are compared to neutrons, uranium nuclei are compared to individual rumor receivers, and fission barriers are compared to individual active propagation thresholds. Second, the process of nuclear fission is analyzed and the degree of energy accumulation is used to compare the social impact of online rumors. Finally, the online rumor propagation model based on nuclear fission is constructed. Through experimental simulation, it has been shown that compared to classic infectious disease models, this model can better describe the propagation process of rumors in social networks. Through research and analysis, suggestions for suppressing rumors have been proposed, providing new ideas and references for future researchers. [ABSTRACT FROM AUTHOR]

The total fission energy released in a criticality accident involving fissile solution boiling tends to be high because the relatively high fission power continues during boiling. Simulating fission power change correctly during boiling seems essential to estimate the total fission energy. Fission power during boiling changes depending on fissile concentration and volume as the solution evaporates. In this study, we investigated the effect of concentration and volume change on estimated total fission energy for a long time of boiling. We introduced a model calculating the evaporation of fissile solution into the modified quasi-steady-state method to simulate power change during boiling. Three CRAC experiments and the Idaho Chemical Processing Plant (ICPP) criticality accident in 1959 were analyzed. As a result, the calculated energy considering concentration and volume change during boiling reproduced the measured energy well. [ABSTRACT FROM AUTHOR]

To validate the nuclear data in JENDL-4.0 and obtain information to improve their accuracy, the analysis of the measured nuclide inventories of the high-burnup PWR UO2 and BWR MOX fuels in the REBUS program was performed by using MVP-BURN with the nuclear library and burnup chain based on JENDL-4.0, and the ratios of the calculated and measured inventories (C/Es) were compared with the previous results obtained with JENDL-3.2 or JENDL-3.3. As a result, an improvement in the accuracy of the neutron cross-sections and cumulative fission yields (CFYs) in JENDL-4.0 was confirmed for the inventories of 236U, 238Pu, 239Pu, 241Pu, 242Pu, 241Am, 243Cm, 244Cm, 133Cs, 145Nd, 148Sm, 149Sm, 151Sm, and 153Eu of the PWR UO2 fuel and 239Pu, 241Pu, 242Pu, 241Am, 243Am, 243Cm, 244Cm, 246Cm, 134Cs, 144Ce, 145Nd, 147Sm, and 154Eu of the BWR MOX fuel. Based on the C/Es obtained with JENDL-4.0, the directions to improve the neutron cross-sections and CFYs were tentatively proposed. They included the neutron capture cross-sections of 234U, 236U, 237Np, 238Pu, 241Am, 242Cm, 245Cm, 143Nd, 147Pm, 154Eu, and 155Eu, the fission cross-sections of 243Cm and 245Cm, and the CFYs of 144Nd, 147Pm, and 155Eu. [ABSTRACT FROM AUTHOR]

Objective: Lung adenocarcinoma poses a major global health challenge and is a leading cause of cancer-related deaths worldwide. This study is a review of three molecular biomarkers screened by machine learning that are not only important in the occurrence and progression of lung adenocarcinoma but also have the potential to serve as biomarkers for clinical diagnosis, prognosis evaluation and treatment guidance. Methods: Differentially expressed genes (DEGs) were identified using comprehensive GSE1987 and GSE18842 gene expression databases. A comprehensive bioinformatics analysis of these DEGs was conducted to explore enriched functions and pathways, relative expression levels, and interaction networks. Random Forest and LASSO regression analysis techniques were used to identify the three most significant target genes. The TCGA database and quantitative polymerase chain reaction (qPCR) experiments were used to verify the expression levels and receiver operating characteristic (ROC) curves of these three target genes. Furthermore, immune invasiveness, pan-cancer, and mRNA-miRNA interaction network analyses were performed. Results: Eighty-nine genes showed increased expression and 190 genes showed decreased expression. Notably, the upregulated DEGs were predominantly associated with organelle fission and nuclear division, whereas the downregulated DEGs were mainly associated with genitourinary system development and cell-substrate adhesion. The construction of the DEG protein-protein interaction network revealed 32 and 19 hub genes with the highest moderate values among the upregulated and downregulated genes, respectively. Using random forest and LASSO regression analyses, the hub genes were employed to identify three most significant target genes.TCGA database and qPCR experiments were used to verify the expression levels and ROC curves of these three target genes, and immunoinvasive analysis, pan-cancer analysis and mRNA-miRNA interaction network analysis were performed. Conclusion: Three target genes identified by machine learning: BUB1B, CENPF, and PLK1 play key roles in LUAD development of lung adenocarcinoma. [ABSTRACT FROM AUTHOR]

Because of the neutron's special properties, neutron diffraction may be considered one of the most powerful techniques for structure determination of crystalline and related matter. Neutrons can be released from nuclear fission, from spallation processes, and also from low-energy nuclear reactions, and they can then be used in powder, time-of-flight, texture, single crystal, and other techniques, all of which are perfectly suited to clarify crystal and magnetic structures. With high neutron flux and sufficient brilliance, neutron diffraction also excels for diffuse scattering, for in situ and operando studies as well as for high-pressure experiments of today's materials. For these, the wave-like neutron's infinite advantage (isotope specific, magnetic) is crucial to answering important scientific questions, for example, on the structure and dynamics of light atoms in energy conversion and storage materials, magnetic matter, or protein structures. In this primer, we summarize the current state of neutron diffraction (and how it came to be), but also look at recent advances and new ideas, e.g., the design of new instruments, and what follows from that. [ABSTRACT FROM AUTHOR]

The nature of the spin distribution (SD) of fragments of low-energy induced and spontaneous double fission of nuclei is described theoretically. For two deformed fission prefragments, a mechanism for pumping large values of their relative orbital momenta and spins , due to the combined influence of bending and wriggling vibrations, is established, and analytical formulas for describing SP within the framework of such a mechanism are obtained for the first time. It is emphasized that for this mechanism the nucleus remains "cold" in the fission process, while in the statistical model it heats up to temperatures of MeV. A comparison of the calculated SDs for forced double fission of actinide nuclei and with the available experimental data showed reasonable agreement both in terms of the magnitude of the average spin values and in the sawtooth shape of the dependence of SP on the atomic number of fragments, which confirms the reliability of the pumping mechanism of large spin values of deformed fission fragments. For spontaneous double fission of the nucleus , possible reasons for the discrepancy between the theoretical SD and the experiment are indicated. [ABSTRACT FROM AUTHOR]

When studying hazardous materials such as spent nuclear fuel (SNF), the minimisation of sample volumes is essential, together with the use of chemically-similar surrogates where possible. For example, the bulk behaviour of urania (UO2) can be mimicked by appropriately-engineered thin films of sufficient thickness, and inactive materials such as ceria (CeO2) can be used to study the effects within radioactive systems used to fuel nuclear fission. However, thin film properties are sensitive to the preparative method, many of which require the use of highly toxic precursors and specialised apparatus (e.g., chemical vapour deposition). To address this, we present the development of a flexible, tuneable, scalable method for the preparation of thin-film CeO2 SIMFUEL models with a thickness of ≈5 μm. The effects of γ irradiation (up to 100 kGy) and dopants including trivalent lanthanides (Ln3+) and simulant ε-particles on the structure and long-term leaching of these systems under SNF storage conditions were explored, alongside the context of this within further work. It was found that the sensitivity of CeO2 films to reduction upon irradiation, particularly in the presence of simulant ε-particles, resulted in increased leaching of Ce (as CeIII), while trivalent lanthanides (Nd3+ and Eu3+) had a minimal effect on Ce leaching. [ABSTRACT FROM AUTHOR]

This is a paper on experimental studies performed in the 1940s at the University of Notre Dame accelerator laboratory to investigate radiation effects on materials and also to probe the efficiency of atmospheric cooling of the fireball created by a nuclear fission device. This was a critical question to be addressed during the early phases in the development of the Manhattan project, which was again raised in the film Oppenheimer, posing the question whether "a bomb can set the atmosphere on fire." This paper brings forth the formerly classified reaction studies performed at Notre Dame's Nuclear Science Laboratory to answer this question. [ABSTRACT FROM AUTHOR]

The pre-scission neutron multiplicity and dissipation strength are studied for a systematic understanding of the role of entrance-channel in fusion-fission dynamics using the statistical model formalism. The measured pre-scission neutron multiplicity is found to be higher for symmetric reactions as compared to the asymmetric ones for a given compound nucleus, with the exception of a few reaction channels, where the presence of quasi-fission affects the neutron yield. The calculated pre-scission neutron multiplicities are compared with the experimentally measured values and it is found that for the majority of reactions, the calculated values of pre-scission neutron multiplicities are under-estimated. The underestimation of pre-scission neutron multiplicity indicates that dissipation is required in the fission channel to reproduce the experimental data. The systematic behaviour of pre-scission neutron multiplicity and dissipation strength as a function of fissility of the compound nucleus is also explored for the select energy ranges. It is found that the pre-scission neutron multiplicity shows nearly increasing behaviour as a function of fissility of the compound nucleus, whereas, dissipation does not seem to follow such an increasing trend for the studied reactions. [ABSTRACT FROM AUTHOR]

In fusion, the validation of turbulent transport models is undertaken with the goals of making basic physics discoveries as well as for development of new predictive models to improve the operation and enhance the performance of existing and future fusion reactors. A fusion industry is just beginning to emerge globally. Like fission, validation in fusion energy research is a vibrant research area, but unlike fusion, a fission industry exists. The fission power industry motivates validation efforts, often performed at universities with small-scale experiments and advanced models and simulations developed in-house. Because fission research spans basic physics and applications, and addresses near-term and long-term industry interests, validation is thriving. This perspective article describes the validation of turbulent transport models in both fusion research and fission research, draws parallels between the validation methods and techniques used in two areas of the fields, and presents an outlook for thriving university fusion and fission research programs underpinned by a virtual cycle of basic and applied research that supports industry needs as well as tackling intellectual grand challenges. [ABSTRACT FROM AUTHOR]

Objective: To investigate the safety and prognosis of enbloc or piecemeal removal after enbloc resection of a gastric GIST by comparing the clinical data of endoscopic en block resection and piecemeal removal (EP) and en block resection and complete removal (EC) of gastric GISTs. Methods: A total of 111 (43 endoscopic piecemeal, and 68 complete removal) patients with gastric GIST's ≥ 2 cm in diameter who underwent endoscopic therapy from January 2016 to June 2020 at the First Affiliated Hospital of Zhengzhou University were retrospectively analyzed. In all cases, it was ensured that the tumor was intact during the resection, however, it was divided into EP group and EC group based on whether the tumor was completely removed or was cut into pieces which were then removed. The patients' recurrence-free survival rate and recurrence-free survival (RFS) were recorded. Results: There was no statistically significant difference in RFS rates between the two groups (P = 0.197). The EP group had relatively high patient age, tumor diameter, risk classification, and operation time. However, there was no statistically significant difference in the number of nuclear fission images, postoperative hospitalization time, postoperative fasting time, complication rate and complication grading between the two groups (P > 0.05). Conclusion: Endoscopic piecemeal removal after en block resection of gastric GIST is safe and effective and achieves similar clinical outcomes as complete removal after en block resection. [ABSTRACT FROM AUTHOR]

We describe the use of the radionuclide 85Kr, which is produced by nuclear fission and has a half-life of 10.74 years, to determine the age of spent nuclear fuel. [ABSTRACT FROM AUTHOR]

This paper investigates the possibility of restoring the trajectory of fission fragments using thick targets that are opaque to the fragments, by analyzing the angular distribution of prompt neutrons. Employing thick targets in experimental studies with low-intensity neutron beams accelerate the accumulation of statistics, thereby facilitating the study of subtle effects, such as the rotation (ROT) effect which sheds light on the deformation and rotational behavior of fission fragments. The paper details the experimental techniques used, presents the results of neutron yield measurements from the fission of 235U with cold and “warm” (60 meV) neutrons in the range of angles from 0 to 360( (in 22.5( increments). The analysis of these is also presented. [ABSTRACT FROM AUTHOR]

This paper is an overview of the results obtained by a collaborative team of researchers from the Institute for Nuclear Research, Russian Academy of Sciences (INR RAS), and State Scientific Center of the Russian Federation—Institute of Physics and Power Engineering (SSC RF—IPPE) using the SVZ-100 lead slowing-down neutron spectrometer. The study focuses on measuring the fission cross sections of americium isotopes 241Am, 242mAm, and 243Am when bombarded by neutrons with energies below 100 keV. The high efficiency of the SVZ-100, facilitated by its substantial working-substance mass (100 t of high-purity lead) and neutron generation through proton irradiation with a 209-MeV accelerator at the INR RAS, enables the investigation of neutron-nuclear processes in microgram samples of radioactive nuclides, which is unattainable in experiments using time-of-flight spectrometry. Unique scientific information is acquired through lead slowing-down neutron spectrometry by collaborative research efforts at the INR RAS and SSC RF—IPPE. This information partially fills gaps or complements existing but often contradictory or insufficient data from experiments conducted on both time-of-flight installations and lead slowing-down neutron spectrometers at other research centers. The results of collaboration of the INR RAS and SSC RF—IPPE are documented in international nuclear data repositories, indicating, in several instances, the need for adjustments to recommended approximating and calculated values. Information is given on some implemented and planned studies on neutron fission cross sections of americium isotopes at other centers following completion of the collaboration of the INR RAS and SSC RF—IPPE. [ABSTRACT FROM AUTHOR]

The article outlines findings from a comparative analysis of the effectiveness of doping CeO2 ceramics with a stabilizing additive Y2O3 on alterations in the strength and thermophysical parameters of ceramics under high-temperature irradiation with heavy ions comparable in energy to fission fragments of nuclear fuel, which allows, during high-temperature irradiation, to simulate radiation damage that is as similar as possible to the fission processes of nuclear fuel. During the studies, it was found that the addition of a stabilizing additive Y2O3 to the composition of CeO2 ceramics in the case of high-temperature irradiation causes an increase in stability to swelling and softening because of a decrease in the thermal expansion of the crystal lattice by 3–8 times in comparison with unstabilized CeO2 ceramics. It has been determined that the addition of a stabilizing additive Y2O3 leads not only to a rise in the resistance of the crystal structure to deformation distortions and swelling, but also to a decrease in the effect of thermal expansion of the crystal structure, which has an adverse effect on the structural ordering of CeO2 ceramics exposed to irradiation at high temperatures. [ABSTRACT FROM AUTHOR]