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2025
In order to obtain the Single-Event Burnout (SEB) characteristics of the diamond Schottky barrier diode (SBD), the two-dimensional model of the device was established by using the TCAD simulation tool, and the positive characteristics of the experimental diamond Schottky diode were used to calibrate the established simulation model. On this basis, the diamond SBD devices irradiated by high-energy Ge ions were studied by combining the SRIM and TCAD software, and the influence of reverse bias voltage, linear energy transfer (LET) value, and the depth of incidence on the single event effect during the irradiation process was revealed. The simulation results show that the increase in lattice temperature caused by the incident of heavy ions is positively correlated with the bias voltage, LET value, and incident depth. When the bias voltage, LET value, and depth of incidence reach a certain level, the local lattice temperature inside the device may exceed the melting point of the diamond material, resulting in the occurrence of SEB. Conversely, when these parameters are at low levels, the increase in lattice temperature caused by the incident of heavy ions is not sufficient to reach the melting point of the diamond, thus avoiding the occurrence of burnout. The related work provides a solid theoretical basis for the reliability evaluation and anti-radiation reinforcement design of diamond SBD power devices against SEB.- Book : 1(2)
- Pub. Date : 2025
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2025
Mitochondrial neurogastrointestinal encephalomyopathy syndrome (MNGIE), also known
as mitochondrial gastrointestinal encephalopathy, is an extremely rare hereditary metabolic disorder
caused by mutations in the nuclear gene TYMP, which encodes the enzyme thymidine phosphorylase
(TP). The subsequent systemic accumulation of deoxyribonucleosides leads to mutations in the mitochondrial genetic material and ultimately to the failure of the organelle itself. The degenerative nature
of the disease and the intricate nature of its clinical symptoms effectively hinder proper diagnosis,
which, with the life expectancy of MNGIE patients estimated at 37 years, significantly complicates its
treatment. Currently, available therapeutic approaches, based on symptomatic treatment, are slowly
giving way to newly developed experimental therapies. In vitro and in vivo models have played a key
role in this topic, contributing to the deepening and understanding of the disease mechanisms over
the years, thus providing an important foundation for further research and potential therapies. This
review provides a comprehensive overview of the current state of knowledge on MNGIE, with a focus
on current therapeutic options, available disease models, and diagnostic procedures. This review
aims to increase clinical awareness and support the development of more effective treatments and
diagnostics, as well as to provide valuable information that can improve the quality of life and care
of patients with MNGIE.- Book : 374(73)
- Pub. Date : 2025
- Page : pp.64-83
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2025
Inflammation contributes to the onset and development of many diseases, including neurodegenerative diseases, caused by the activation of microglia, leading to neurological deterioration. Nuclear factor-κB (NF-κB) is one of the most relevant pathways for identifying anti-inflammatory molecules. In this study, polygodial and isotadeonal, two drimane sesquiterpene dialdehydes, were isolated from Drimys winteri, a medicinal tree of the Mapuche people in Chile. Isotadeonal, or epi-polygodial, was obtained from polygodial by epimerization in basic media (60% yield, Na2CO3, r/t, 24 h). Both sesquiterpenoids were evaluated on the NF-κB pathway, with the result that isotadeonal inhibited the phosphorylation of IκB-α at 10 μM with higher potency by Western blotting. The final inhibition of the pathway was evaluated using a SEAP reporter (secreted alkaline phosphatase) on THP-1 cells. Isotadeonal inhibited SEAP with higher potency than polygodial, quercetin, and CAPE (phenethyl ester of caffeic acid). In silico analysis suggests that the α-aldehyde of isotadeonal adopts a more stable conformation in the active pocket of IκB-α than polygodial.- Book : 30(7)
- Pub. Date : 2025
- Page : pp.1555-1555
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2025
Reduction quality is associated with fracture prognosis. Displaced subcapital femoral neck fracture has highest possibility of avascular necrosis of femoral head and non-union among the femoral neck fractures, which commonly necessitate revisions or hip replacement. This study introduces for the first time of using hip arthroscope to directly visualize and assist the reduction of displaced subcapital femoral neck fracture when closed reduction is unsatisfactory. Due to the minimally invasive advantage of arthroscopic assistance, radiation exposure or intraoperative bleeding can be reduced, open reduction is avoided so that the blood supply of femoral head can be preserved. Through direct visualization, the complete removal of hematoma and fracture debris can be achieved, which is not possible with closed reduction, and can potentially reduce the risk of non-union during bone healing.- Book : ()
- Pub. Date : 2025
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2025
- Book : ()
- Pub. Date : 2025
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2025
Abstract
Determining the effects of ionizing radiation from unintended exposure in a nuclear event requires the identification of relevant biomarkers and development methods to retrospectively estimate the absorbed dose. Melanin, a biologically important natural pigment found in hair, shows promise as a biomarker to assess potential radiation exposure. We investigated Raman spectroscopy as a rapid and non-invasive technique to assess changes in melanin from the hair of C57BL/6 mice to gamma radiation between 0-4 Gy. Two excitation wavelengths (532 nm and 785 nm) were employed to probe the melanin response for changes with radiation exposure. Excitation wavelength dependent variation in Raman features indicate resonance Raman effects, where 785 nm excitation is more sensitive to the effects of gamma radiation. Melanin-specific Raman features were identified as potential biomarkers for gamma radiation exposure and used to distinguish between irradiated and non-irradiated mice. Partial Least Square Discriminant Analysis (PLS-DA) models of exposure exhibited enhanced sensitivity to irradiation at 785 nm excitation and yielded a sensitivity of 88% and a specificity of 83%. Mice were classified with 100% sensitivity and specificity up to day 7 at a known time point. A decline in specificity and classification accuracy correlated with alterations in melanin's spectra after more than 7 days following irradiation. Regression models of the Raman spectrum determined exposed dose with a precision of < 1 Gy at a known exposure timepoint. This non-invasive approach offers promising applications in radiation biodosimetry and medical monitoring, providing retrospective detection of gamma radiation exposure at clinically relevant doses.- Book : ()
- Pub. Date : 2025
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2025
Abstract
Trifluridine/Tipiracil (FTD/TPI, TAS102) has been approved for the treatment of patients with colorectal cancer (CRC) for its promising anticancer activity enabled by its incorporation into double strands during DNA synthesis. However, the mechanisms underlying the anticancer targets of FTD/TPI remain not fully understood. Here we report our observation of the activation of ferroptosis in CRC by FTD/TPI. Mechanistically, FTD/TPI directly promotes the ubiquitination and degradation of MDM2, thereby stabilizing the p53. Nuclear accumulation of p53 subsequently downregulates SLC7A11 expression, leading to ferroptosis. Furthermore, we observed that FTD/TPI combined with sulfasalazine (SAS), a system Xc– inhibitor, works in a synergistic manner to induce ferroptosis and further inhibit the proliferation of CRC cells. Finally, we confirmed the synergistic effect of SAS and FTD/TPI on patient-derived organoids in vitro and patient-derived xenograft mouse models in vivo. Our findings are the first to reveal that FTD/TPI induces ferroptosis via the p53-SLC7A11 axis and that SAS enhances the sensitivity and therapeutic effect of FTD/TPI. These findings suggest that the synergistic effect of FTD/TPI and SAS may represent a new therapeutic strategy for patients with CRC.- Book : 16(1)
- Pub. Date : 2025
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2025
Abstract
Recent experimental results from the Atomki collaboration have reported the observation of anomalous effects in Beryllium, Helium and Carbon nuclear transitions that could hint at physics beyond the Standard Model. However, the MEG-II experiment has recently found no significant anomalous signal in the Beryllium transition 8Be⋆ → 8Be + e
+
e
−. In view of this result, we critically re-examine the possible theoretical interpretations of the anomalies observed by the Atomki experiment in terms of a new boson X with mass around 17 MeV. The present work aims to study the phenomenology of a spin-2 state and revisit the possibility of a pure CP-even scalar, which was initially dismissed due to its inability to explain the Beryllium anomalous signal. Our analysis shows that a spin-2 state is highly disfavoured by the SINDRUM constraint while a scalar boson could explain the Helium and Carbon anomalies while being compatible with other experimental constraints.- Book : 2025(4)
- Pub. Date : 2025
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2025
Abstract
Koalas are arboreal herbivorous marsupials, endemic to Australia. During the late 1800s and early 1900s, the number of koalas declined dramatically due to hunting for their furs. In addition, anthropogenic activities have further decimated their available habitat, and decreased population numbers. Here, we utilise 37 historic and 25 modern genomes sampled from across their historic and present geographic range, to gain insights into how their population structure and genetic diversity have changed across time; assess the genetic consequences of the period of intense hunting, and the current genetic status of this iconic Australian species. Our analyses reveal how genome-wide heterozygosity has decreased through time and unveil previously uncharacterised mitochondrial haplotypes and nuclear genotypes in the historic dataset, which are absent from today’s koala populations.- Book : ()
- Pub. Date : 2025
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2025
A wideband high-efficiency circularly polarized (CP) dual-coil antenna array is presented for 60-GHz applications in this letter. The proposed CP dual-coil antenna is composed of a resonant substrate-integrated cavity (SIC) and a pair of centrally symmetrical coils, which are fed differentially by a substrate-integrated waveguide (SIW) coupling slot. A novel sequential rotation feeding technique is introduced to enhance the axial ratio (AR) and impedance bandwidths of both the 2 × 2 subarray and the 4 × 4 array. The proposed feeding network significantly improves radiation efficiency. The measured results of the fabricated prototype indicate that the proposed array achieves an impedance bandwidth of 20.8% (54.6–67.3 GHz) for |S11| ≤ −10 dB, a 3-dB AR bandwidth of 21.5% (54–67 GHz), a high radiation efficiency of 96.6%, and a peak gain reaching 19.3 dBic at 58 GHz. The proposed circularly polarized (CP) antenna element and array design stand out as strong contenders for 60-GHz wireless applications.- Book : 25(7)
- Pub. Date : 2025
- Page : pp.2211-2211
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