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2025
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- Pub. Date : 2025
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2025
AbstractOne hypothesized mechanism that triggers deep‐focus earthquakes in oceanic subducting slabs below ∼300 km depth is transformational faulting due to the olivine‐to‐spinel phase transition. This study uses finite element modeling to investigate phase transformation‐induced stress redistribution and material weakening in olivine. A thermodynamically consistent constitutive model is developed to capture the evolution of phase transformation in olivine under different pressure and temperature conditions. The overall numerical model enables considering multiscale material features, including the polycrystalline structure, mesoscale heterogeneity, and various phases or variants of phases at the microscopic level, and accounts for viscoplastic behaviors with thermo‐mechanical coupling effects. The model is validated with several benchmarks, including a phase diagram of phase transformation from olivine to spinel. The validated model is used to study the interactive behaviors between defects (heterogeneity) and phase transformation. The simulation results reveal that spinel formation under pressure initiates near inclusions and along the grain boundaries, consistent with experimental observations. At lower temperatures, the transformation leads to the formation of thin conjugate bands of spinel diagonal to the compression loading direction. Local stress analysis along these bands also suggests the initiation of faulting. In contrast, the numerical results at higher transformation rates show that significant spinel formation occurs over a larger area at elevated temperatures, leading to ductile behavior, which agrees with experimental findings. Numerical simulation of multiple inclusions under confined pressure also shows the formation of a network of spinel bands resembling phase‐transformation patterns observed in the laboratory experiments. Additionally, stress softening patterns due to phase transformation are similar to experimental observations.- Book : 130(2)
- Pub. Date : 2025
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2025
Abstract
Purpose
To investigate the presence of tubulation in the outer nuclear layer of patients with Bietti crystalline dystrophy (BCD) using optical coherence tomography (OCT) and evaluate its relationship with visual field, visual field progression, and retinal volume.
Methods
This retrospective cross-sectional study included 37 patients diagnosed with BCD who underwent spectral-domain OCT examination. OCT examinations and Humphrey visual field tests (10–2 program) were conducted. We performed correlation analyses to assess the correlation of the number of tubulations with the visual field parameters and retinal volume. We also compared the number and prevalence of tubulations in groups based on median values of the parameters. The primary outcome measure was the number and prevalence of tubulations.
Results
The average age of the participants was 58.7 ± 9.6 years. The mean deviation (MD) value was −25.0 ± 9.0 decibels (dB). The MD slope value during an average follow-up period of 5.9 ± 3.8 years was −0.91 ± 1.02 dB/year. The number of tubulations tended to increase as the MD values worsened (P = 0.055, r = −0.33). Moreover, the number (P = 0.48) and prevalence (P = 0.42) of tubulations tended to be higher in the group with lower MD values. The number of tubulations decreased with worsening logarithmic minimum angle of resolution (logMAR) (P = 0.68, r = −0.07). The prevalence of tubulations was higher in the group with poorer logMAR (P = 0.068). We observed no significant correlations between the number of tubulations and the retinal outer, inner, or center volume (P = 0.46, r = −0.13; P = 0.76, r = 0.05; P = 0.47, r = 0.12, respectively). However, the prevalence of tubulations in the group with smaller retinal center volume was lower (P = 0.054).
Conclusion
The number of tubulations correlated with the severity of visual field loss in patients with BCD; however, it did not correlate with visual field progression or retinal volume measurements. Further studies are needed to understand the development of tubulations and their implications for retinal atrophy in BCD.
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2025
- Book : ()
- Pub. Date : 2025
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2025
- Book : ()
- Pub. Date : 2025
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2025
Purpose: Peptide Receptor Radionuclide Therapy (PRRT) with 177Lu-DOTATATE (177 Lu DOTA-TATE therapy is a form of PRRT which targets Somatostatin Receptors (SSR). It is a form of targeted drug delivery, which is applicable to treat neuroendocrine tumors. PRRT applications are continuously expanding in most departments of nuclear medicine in Iran, but the best of all, no one has studied the mean doses of organs of the patients. This research aims to specify the absorbed dose to patients for the treatment of neuroendocrine tumors using imaging with 177Lu-[DOTA0-Tyr3] octerotate.
Materials and Methods: Whole body planar scintigraphy images were collected for 10 patients, which are used as the basis for the personalized patient dosimetry calculations. The patients had a mean age of 53.5 ± 12 years (ranging from 36 to 70 years) and imaging data were collected at roughly 0 to 2 hours, 4 to 6 hours, 18 to 24 hours, and 36 to 48 hours after the injection of 6401± 628.4 MBq (range of 5500 MBq-7400 MBq) of 177Lu-[DOTA0-Tyr3] octerotate. Models of time-activity were established for different organs. Finally, using absorbed dose formulation and IDIAC-Dosage software, the mean absorbed dose in the organs was determined.
Results: Mean calculated dose in the kidney and liver were obtained as 0.30-0.82 mGy/ MBq, and 1.05-2.11 mGy/MBq, respectively.
Conclusion: Based on the results, PRRT therapy is a safe method for the treatment of castration-resistant neuroendocrine cancer patients in terms of patient dose. Large inter-individual differences in organ dose were discovered, highlighting the importance of patient-specific dosimetry and treatment planning in the treatment with 177Lu-DOTATATE.- Book : ()
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2025
- Book : ()
- Pub. Date : 2025
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2025
Neoadjuvant chemoradiation therapy (NCRT) is an underutilized treatment in breast cancer but may improve outcomes by impacting the tumor immune microenvironment. The aim of this study was to evaluate NCRT’s impact on recurrence and the role of tumor-infiltrating lymphocytes (TILs) in treatment response. We hypothesized that NCRT reduces recurrence by upregulating TILs. Patients with locally advanced breast cancer (LABC) were treated with NCRT. Stage IIB to III patients with any molecular subtypes were eligible. The patients were matched for age, stage, and molecular subtype by a propensity score to a concurrent cohort receiving standard neoadjuvant chemotherapy (NCT) followed by adjuvant radiation. The objective of this study was to assess the patients in terms of the pathological complete response (pCR), TIL counts prior to and following treatment, and locoregional recurrence. The median follow-up was 7.2 years. Thirty NCRT patients were successfully matched 1:3 to ninety NCT patients. The NCRT cohort had no regional and locoregional recurrences (p = 0.036, (hazard ratio) HR [0.25], 95% confidence interval (CI) [0.06–0.94] and p = 0.013, HR [0.25], 95% CI [0.08–0.76], respectively), compared to 17.8% of the NCT cohort. The NCRT group had significantly more pCRs, and TILs were increased in the post-treatment pCR specimens. NCRT can improve outcomes in LABC patients, with a higher pCR and significantly lower locoregional recurrence/higher recurrence-free survival. Further trials are needed to evaluate the role of NCRT in all breast cancer patients.- Book : 32(2)
- Pub. Date : 2025
- Page : pp.85-85
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2025
Abstract
Background
Brain metastases from Mucoepidermoid carcinoma (MEC) of the parotid gland is extremely rare. To our best knowledge, this is the second report of BM from MEC of parotid gland.
Case presentation
We report the case of a 61-year-old man who was surgically treated for mucoepidermoid carcinoma classified as T3N1M0 and was admitted because of multiple brain metastases from this tumor. He underwent surgery for cerebellar metastases and underwent adjuvant radiotherapy.
Conclusion
In this article, the authors report a case of brain metastases from parotid MEC treated by resection and radiation therapy. A review of the literature did not reveal any other cases of this type.
- Book : 40(1)
- Pub. Date : 2025
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2025
In the present context of a sharp aggravation of interstate rivalry and escalation of traditional and new threats, the importance of policy, forces and means of strategic deterrence in ensuring Russia’s national security cannot be overstated. Fundamental decisions on the development of strategic deterrence capabilities were made by the Russian leadership back in the late 1990s. These decisions were based on the long-term political and military forecasts first made by the Ministry of Defense and the Defense Council and then furthered by the Security Council of the Russian Federation. This paper examines how these decisions were put into practice in the subsequent years and how they have permeated the concept of strategic deterrence in Russia’s updated national security policy. The first section of the article identifies the key forces and facilities underlying the policy of the Russian Federation in the field of strategic nuclear deterrence. The author emphasizes that this policy is defensive in its nature and in terms of material capacities is based on achievements of Russian science and industry in general and the defense industry in particular. These advancements, in turn, rely on the foundations laid down in the USSR, and at the same time result from the timely modernization of Russia’s nuclear triad. The second section analyzes the role of non-nuclear deterrence in the national security policy of Russia. The author notes that a formidable threat of using a high-precision long-range conventionally-armed carrier within the framework of non-nuclear (‘pre-nuclear’) deterrence can effectively complement the nuclear deterrence system. That said, the author concludes that the solution to the problem of ensuring both nuclear and non-nuclear deterrence requires working out a large number of different scenarios, not only political ones, but also of a purely military, strategic and even tactical nature. It also necessitates the coordinated and systematic work of both military and civilian specialists representing the widest range of applied and fundamental disciplines.- Book : 16(4)
- Pub. Date : 2025
- Page : pp.11-31
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