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  • 2025

    Lithium is a metal with a highly promising outlook for future global demand. Its industrial processing relies on two primary methods: production from brines through solar evaporation ponds and production from rock sources via flotation, roasting, and subsequent leaching. Chile is currently the world’s second-largest producer of lithium, surpassed only by Australia. However, Chile’s lithium production process is significantly advantaged by the exceptionally high lithium concentration in the Salar de Atacama—the highest in the world—and the region’s high solar radiation, which enables the most cost-effective solar evaporation process globally. Despite these comparative advantages, Chile’s lithium production has stagnated in recent years. This stagnation can be attributed to the need for more flexible legislation surrounding the lithium industry or an increase in the number of CEOLs (Lithium Exploitation Contracts) to regain its position as the leading global producer of lithium. Furthermore, increased investment in national universities and research centers is essential to foster the development and implementation of new, clean technologies for future projects. By addressing these challenges, Chile has the potential to solidify its role as a key player in the global lithium market while promoting sustainable industrial practices.
    • Book : 14(2)
    • Pub. Date : 2025
    • Page : pp.33-33
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  • 2025

    AbstractBackgroundInput data curation and model training are essential, but time‐consuming steps in building a deep‐learning (DL) auto‐planning model, ensuring high‐quality data and optimized performance. Ideally, one would prefer a DL model that exhibits the same high‐quality performance as a trained model without the necessity of undergoing such time‐consuming processes. That goal can be achieved by providing models that have been trained on a given dataset and are capable of being fine‐tuned for other ones, requiring no additional training.PurposeTo streamline the process for producing an automated right‐sided breast (RSB) treatment planning technique adapting a DL model originally trained on left‐sided breast (LSB) patients via treatment planning system (TPS) specific tools only, thereby eliminating the need for additional training.MethodsThe adaptation process involved the production of a predicted dose (PD) for the RSB by swapping from left‐to‐right the symmetric structures in association with the tuning of the initial LSB model settings for each of the two steps that follow the dose prediction: the predict settings for the post‐processing of the PD (ppPD) and the mimic settings for the dose mimicking, respectively. Thirty patients were involved in the adaptation process: Ten manual plans were chosen as ground truth for tuning the LSB model settings, and the adapted RSB model was validated against 20 manual plans. During model tuning, PD, ppPD, and mimicked dose (MD) were iteratively compared to the manual dose according to the new RSB model settings configurations. For RSB model validation, only MD was involved in the planning comparison. Subsequently, the model was applied to 10 clinical patients. Manual and automated plans were compared using a site‐specific list of dose‐volume requirements.ResultsPD for the RSB model required substantial corrections as it differed significantly from manual doses in terms of mean dose to the heart (+11.1 Gy) and right lung (+4.4 Gy), and maximum dose to the left lung (+6.4 Gy) and right coronary (+11.5 Gy). Such discrepancies were first addressed by producing a ppPD always superior to the manual dose by changing or introducing new predict settings. Second, the mimic settings were also reformulated to ensure a MD not inferior to the manual dose. The final adapted version of the RSB model settings, for which MD was found to be not significantly different than the manual dose except for a better right lung sparing (‐1.1 Gy average dose), was retained for the model validation. In RSB model validation, a few significant—yet not clinically relevant—differences were noted, with the right lung being more spared in auto‐plans (‐0.6 Gy average dose) and the maximum dose to the left lung being lower in the manual plans (‐0.8 Gy). The clinical plans returned dose distributions not significantly different than the validation plans.ConclusionThe proposed technique adapts a DL model initially trained for LSB cancer for right‐sided patients. It involves swapping the dose predictions from left to right and adjusting model settings, without the need for additional training. This technique—specific to a TPS—could be transposed to other TPS platforms.
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    • Pub. Date : 2025
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  • 2025

    First demonstrated in 1942, subcritical and zero-power critical assemblies, also known as piles, are a fundamental tool for research and education at universities. Traditionally, their role has been primarily instructional and for measuring fundamental properties of neutron diffusion and transport. However, these assemblies could hold potential for modern applications and nuclear research. The Purdue University subcritical pile previously lacked a substantial testing volume, limiting its utility to simple neutron activation experiments for the purpose of undergraduate education. Following the design and addition of a mechanical and electrical testbed, this paper aims to provide an overview of the testbed design and characterize its neutron and gamma flux of the rearranged Purdue subcritical pile, justifying its use as a modern scientific instrument. The newly installed 1.5*10^5 cubic-centimeter volume testbed enables a systematic investigation of neutron and gamma effects on materials and the generation of a comprehensive dataset with the potential for machine learning applications. The neutron flux throughout the pile is calculated using gold-197 and indium-115 foil activation alongside cadmium-covered foils for two-group neutron energy classification. The neutron flux measurements are then used to benchmark a detailed geometrically and materialistic accurate Monte-Carlo model using OpenMC. The experimental measurements reveal the testbed has a neutron environment with a total neutron flux approaching 8.5*10^3 n/cm^2*s and a thermal flux of 5.8*10^3 n/cm^2*s, following the expected diffusion theory behavior. This work establishes the modified Purdue subcritical pile can provide significant neutron and gamma fluxes and a uniquely large volume to enable radiation testing of integral electronic components and as a versatile research instrument with the potential to support microelectronics testing, limited isotope production, and non-destructive imaging while generating valuable training datasets for machine learning algorithms in nuclear applications. [M1]Reference citation is not allowed. Please revise.
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    • Pub. Date : 2025
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  • 2025


    • Book : ()
    • Pub. Date : 2025
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  • 2025

    Background/Objectives: Cervical cancer primarily disseminates through the lymphatic system, with the metastatic involvement of pelvic and para-aortic lymph nodes significantly impacting prognosis and treatment decisions. Sentinel lymph node (SLN) mapping is critical in guiding surgical management. However, resource-limited settings often lack advanced detection tools like indocyanine green (ICG). This study evaluated the feasibility and effectiveness of SLN biopsy using alternative techniques in a high-risk population with a high prevalence of large tumours. Methods: This prospective, observational study included 42 patients with FIGO 2018 stage IA1–IIA1 cervical cancer treated between November 2019 and April 2024. SLN mapping was performed using methylene blue alone or combined with a technetium-99m radiotracer. Detection rates, sensitivity, and false-negative rates were analysed. Additional endpoints included tracer technique comparisons, SLN localization patterns, and factors influencing detection success. Results: SLNs were identified in 78.6% of cases, with bilateral detection in 57.1%. The combined technique yielded higher detection rates (93.3% overall, 80% bilateral) compared to methylene blue alone (70.4% overall, 40.7% bilateral, p < 0.05). The sensitivity and negative predictive values were 70% and 93.87%, respectively. Larger tumours (>4 cm), deep stromal invasion, and prior conization negatively impacted detection rates. False-negative SLNs were associated with larger tumours and positive lymphovascular space invasion. Conclusions: SLN biopsy is feasible in resource-limited settings, with improved detection rates using combined tracer techniques. However, sensitivity remains suboptimal due to a steep learning curve and challenges in high-risk patients. Until a high detection accuracy is achieved, SLN mapping should complement, rather than replace, pelvic lymphadenectomy in high-risk cases.
    • Book : 14(4)
    • Pub. Date : 2025
    • Page : pp.1381-1381
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  • 2025

    The probabilities for γ-ray and particle emission as a function of the excitation energy of a decaying nucleus are valuable observables for constraining the ingredients of the models that describe the deexcitation of nuclei near the particle emission threshold. These models are essential in nuclear astrophysics and applications. In this paper, we have for the first time simultaneously measured the γ-ray and neutron emission probabilities of Pb208. The measurement was performed in inverse kinematics at the Experimental Storage Ring (ESR) of the GSI/FAIR facility, where a Pb208 beam interacted through the Pb208(p,p′) reaction with a hydrogen gas jet target. Instead of detecting the γ rays and neutrons emitted by Pb208, we detected the heavy beamlike residues produced after γ and neutron emission. These heavy residues were fully separated by a dipole magnet of the ESR and were detected with outstanding efficiencies. The comparison of the measured probabilities with model calculations has allowed us to test and select different descriptions of the γ-ray strength function and the nuclear level density available in the literature. Published by the American Physical Society 2025
    • Book : 111(2)
    • Pub. Date : 2025
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  • 2025

    AbstractProtein domains of low sequence complexity are unable to fold into stable, three-dimensional structures. In test tube studies, these unusual polypeptide regions can self-associate in a manner causing phase separation from aqueous solution. This form of protein:protein interaction has been implicated in numerous examples of dynamic morphological organization within eukaryotic cells. In several cases, the basis for low complexity domain (LCD) self-association and phase separation has been traced to the formation of labile cross-β structures. The primary energetic force favoring formation of these transient and reversible structures is enabled by polypeptide backbone interactions. Short, contiguous networks of peptide backbone amino groups and carbonyl oxygens are zippered together intermolecularly by hydrogen bonding as described by Linus Pauling seven decades ago. Here we describe a simple, molecular biological method useful for the identification of localized, self-associating regions within larger protein domains of low sequence complexity.SignificanceThis study describes a molecular biological method for analyzing protein domains of low sequence complexity in search of segments that mediate self-association and consequent phase separation bothin vitroandin vivo. Small regions allowing for self-association correspond to sequences that specify the formation of labile cross-β structural order. When juxtaposed to the C-terminus of GFP, cross-β prone regions suppress fluorescence. A tiled scan of overlapping fragments of the low complexity domain (LCD) of the TDP-43 RNA binding protein pinpointed an evolutionarily conserved sequence of twenty amino acids essential for self-association, phase separation and the formation of nuclear speckles. The screening method described herein should be useful for the analysis of any LCD believed to function via homotypic self-association.
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    • Pub. Date : 2025
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  • 2025

    AbstractBackgroundThe integrity of brain function is at stake due to cerebral ischemia‐reperfusion injury (CIRI), which encompasses mitochondrial dysfunction, autophagy, and neuroinflammation. The role of E2F1 in mediating these processes in microglia during CIRI remains unclear.MethodsA CIRI mouse model was utilized for single‐cell RNA transcriptome sequencing of brain tissues. The research comprised diverse gene expression, gene ontology (GO), and the enrichment of Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. Experimental techniques included oxygen‐glucose deprivation (OGD/R) cell models, RT‐qPCR, Western Blot, ChIP assays, and microglia‐neuron co‐cultures.ResultsA significant aspect highlighted in the study was the involvement of CDK5 in the induction of mitochondrial abnormalities associated with CIRI. Upregulation of E2F1 and CDK5 in post‐CIRI microglia was observed. E2F1 facilitated CDK5 transcription, leading to DRP1 phosphorylation, exacerbating neurotoxic effects. Silencing E2F1 improved neurobehavioral outcomes in CIRI mice.ConclusionsActivation of E2F1‐mediated CDK5 drives mitochondrial division while inhibiting mitophagy in microglia, triggering inflammation, neuronal apoptosis, and exacerbating CIRI damage. Targeting this pathway could offer novel therapeutic strategies for mitigating CIRI‐induced brain injury.Key points Identification of the E2F1/CDK5/DRP1 Axis in CIRI This study reveals that the E2F1 transcription factor upregulates CDK5 expression, which in turn phosphorylates DRP1, promoting excessive mitochondrial fission and inhibiting mitophagy in microglia. This mechanism plays a critical role in cerebral ischemia‐reperfusion injury (CIRI). Mitochondrial Dysfunction and Neuroinflammation The activation of DRP1 leads to mitochondrial fragmentation and excessive ROS accumulation, triggering microglial activation and inflammatory responses, exacerbating neuronal apoptosis and brain injury in CIRI. Therapeutic Potential of E2F1 Silencing Knockdown of E2F1 in microglia effectively reduces mitochondrial damage, restores mitophagy, suppresses inflammation, and improves neurological outcomes in a CIRI mouse model, highlighting a promising therapeutic target for ischemic stroke intervention.
    • Book : 15(2)
    • Pub. Date : 2025
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  • 2025

    ABSTRACTBackgroundThe comparative effectiveness of radiotherapy and surgery for treating intracranial meningioma is unknown.ObjectivesTo compare survival after treatment of suspected intracranial meningioma by either surgery or radiotherapy.AnimalsTwo hundred eighty‐five companion dogs with suspected intracranial meningiomas presenting to 11 specialty clinics in three countries.MethodsParallel cohort comparison study on retrospective data. Dogs diagnosed with intracranial meningioma by board‐certified veterinary neurologists or radiologists and treated by radiotherapy or surgery were identified through medical record searches and presenting and survival data extracted. Lesion site was classified as rostro‐ or caudotentorial and size was measured on contrast magnetic resonance images. Outcome was all‐cause death. Analysis of survival by Cox proportional hazards, including selection for optimal multivariable model using lasso, counterfactual modeling including variables associated with treatment allocation and survival.ResultsOne hundred sixty‐eight dogs received radiotherapy and 117 received surgery. All analyses indicated reduced survival associated with surgery compared to radiotherapy. There was a median survival after surgery of 297 (IQR: 99–768) days compared with 696 (IQR: 368–999) for dogs treated by radiation, associated with a univariable hazard ratio of 1.802 (95% CI: 1.357–2.394). Counterfactual modeling estimated a mean survival of 480 (95% CI: 395–564) days after surgery and 673 (95% CI: 565–782) days after radiotherapy, representing a decrease in survival of 29%. Location and size of the lesion were not associated with survival duration.Conclusions and Clinical ImportanceDogs with suspected intracranial meningioma have substantially superior survival after radiotherapy compared to surgery.
    • Book : 39(2)
    • Pub. Date : 2025
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  • 2025

    Gold nanoparticles (GNPs) have gained significant attention as multifunctional agents in biomedical applications, particularly for enhancing radiotherapy. Their advantages, including low toxicity, high biocompatibility, and excellent conductivity, make them promising candidates for improving treatment outcomes across various radiation sources, such as femtosecond lasers, X-rays, Cs-137, and proton beams. However, a deeper understanding of their precise mechanisms in radiotherapy is essential for maximizing their therapeutic potential. This review explores the role of GNPs in enhancing reactive oxygen species (ROS) generation through plasmon-induced hot electrons or radiation-induced secondary electrons, leading to cellular damage in organelles such as mitochondria and the cytoskeleton. This additional pathway enhances radiotherapy efficacy, offering new therapeutic possibilities. Furthermore, we discuss emerging trends and future perspectives, highlighting innovative strategies for integrating GNPs into radiotherapy. This comprehensive review provides insights into the mechanisms, applications, and potential clinical impact of GNPs in cancer treatment.
    • Book : 15(4)
    • Pub. Date : 2025
    • Page : pp.317-317
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