All 3,287,370 Page 45/328,737
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2025
Background/Objectives: Heterozygous variants in the heterogeneous nuclear ribonucleoprotein C gene (HNRNPC) have recently been reported to cause intellectual developmental disorder-74 (MRD74), a neurodevelopmental disorder with no recurrent diagnostic handles. Affected individuals show variable, non-specific, and subtle dysmorphic features. The degree of developmental delay (DD)/intellectual disability (ID) is also wide, ranging from mild to severe. The mutational spectrum is relatively broad with exon deletions and splice site and frameshift variants distributed along the entire length of the gene leading to HNRNPC loss of function. Only two missense changes located within the RNA-binding motif (RBM) and adjacent linker region of the more abundant isoform (Arg64Trp and Arg99Gln) have been described. Notably, the Arg99Gln amino acid substitution was reported in a subject presenting with a more complex and unique clinical phenotype characterized by distinctive facial features, DD/ID, cochlear aplasia, and bilateral colobomatous microphthalmia, suggesting the possible occurrence of phenotypic heterogeneity. Results: Here, we report the second individual carrying the Arg99Gln change in HNRNPC and having clinical features with a significant overlap with the peculiar phenotype of the previously described subject, supporting the occurrence of a genotype–phenotype correlation. Conclusions: Due to the concomitant occurrence of ocular and cochlear involvement as recognizable diagnostic handles, we propose that the HNRNPCArg99Gln-related phenotype should be considered as a potential differential diagnosis in subjects with ID and major signs of CHARGE syndrome not fulfilling the minimum criteria for a clinical diagnosis.- Book : 16(2)
- Pub. Date : 2025
- Page : pp.176-176
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2025
- Book : ()
- Pub. Date : 2025
- Page :
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2025
Abstract
Fluorite-structured materials such as cerium dioxide (ceria or CeO2), zirconium dioxide (zirconia or ZrO2), uranium dioxide (urania or UO2), and thorium dioxide (thoria or ThO2) are technologically important for solid oxide fuel cells (SOFC) and nuclear fuels. As such, they have an important role in the future energy mix, and their properties under a range of pressure and temperature conditions need to be understood. There is significant research effort on the material properties of classic oxide systems, both from an experimental and theoretical perspective, aiming to improve these systems using doping or external parameters such as strain. Here, we briefly review cation and oxygen diffusion in fluorite-structured materials. Emphasis is given on the impact on the diffusion of external parameters such as strain.- Book : ()
- Pub. Date : 2025
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2025
Long COVID-19, also known as post-acute sequelae of SARS-CoV-2 infection (PASC), involves symptoms or effects that persist for more than 4 weeks after the initial SARS-CoV-2 infection. One contributing factor to this condition is the disruption in the expression of the antioxidant enzyme Nuclear Factor Erythroid-2 (Nrf2) induced by the COVID-19 infection. Apigenin and related flavonoids, known for their diverse pharmacological activities, including potent antioxidant properties, have emerged as promising candidates for Long COVID-19 therapy. These compounds, particularly apigenin, are recognized for their ability to modulate oxidative stress and inflammation, making them potential activators of the Nrf2 pathway. This study aims to predict the activity of apigenin and its related flavonoids as Nrf2 activators using molecular modeling and molecular dynamics (MD) techniques, providing insights into their therapeutic potential in managing Long COVID-19. The findings from the molecular modeling analysis indicate that apigenin has a favorable affinity, with a free energy value (ΔG) of −6.40 kcal/mol. Additionally, MD simulation results demonstrate the strong stability of the Keap1-apigenin complex, with an average Root Mean Square Deviation (RMSD) value below 0.20 nm and the lowest average Root Mean Square Fluctuation (RMSF) value of 0.86 nm. Using the Molecular Mechanics/Generalized Born Surface Area (MM-GBSA) calculation method, the binding affinity of the Keap1-apigenin complex yields a lower free energy value (ΔG) of −67.039 kJ/mol, consistent with the molecular modeling results. Apigenin also exhibits the ability to inhibit the binding of Nrf2 to the hydrophobic surface of Keap1, with a total energy value of 993.266 kcal/mol and binding affinity value of −1.162 kJ/mol through peptide−receptor docking. In conclusion, the comprehensive results suggest that apigenin has the potential to be a lead compound for developing Nrf2 activators specifically designed for Long COVID-19 therapy.- Book : 15(3)
- Pub. Date : 2025
- Page : pp.1493-1493
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2025
Although Pakistan's economy depends heavily on the livestock industry, animal health is greatly impacted by tick infestation and illnesses spread by ticks. This study evaluated the morphological traits, risk factors, and prevalence of ticks in four districts within the Sargodha Division. Between February and June 2021, 1,067 ruminants (cows, buffaloes, goats, and sheep) from 40 farms were watched. The ITS-2 nuclear gene (750 bp) in 10 tick species was the object of PCR detection. The total infestation rate was 32.10%, with Khushab having the lowest percentage (24.71%) and Mianwali having the highest (54.44%). Goats (16.41%), sheep (27.38%), buffaloes (33.73%), and cows (41.5%) were the most affected species. Male buffaloes (59.37%) were more infected than females (33.58%), while female cows (45.10%) were more infested than males (31%). The distribution of ticks differed by species and sex; in cows and buffaloes, the most afflicted regions were the udder and tail, respectively. Ticks were mostly detected in the ears of sheep and goats and concentrated on the testicles of males. The major risk factors were the summer season, inadequate waste clearance, dogs afflicted with ticks, communal living, grazing systems, and poor tick control techniques. According to morphological studies, there is just one soft tick species, Ornithodoros erraticus, and hard ticks from the genera Rhipicephalus, Hyalomma, and Ixodes. Four tick species had positive bands (750 bp) validated by PCR testing. The study emphasizes the necessity for efficient tick management methods by highlighting the epidemiological implications of species, sex, and tick dispersion patterns in infection rates.- Book : 13(02)
- Pub. Date : 2025
- Page : pp.217-229
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2025
This study is focused on the sorption properties and the changes in the structure and state of Ti-25Al-25Nb (at.%) system alloys under thermal cyclic loading. These samples were produced by combining high-energy processing methods through mechanization and spark plasma sintering in the temperature range of 1100–1300 °C, followed by two-stage heat treatment at temperatures of 800 °C and 1250 °C. Thermal cyclic experiments on hydrogen sorption/desorption with samples of the Ti-25Al-25Nb (at.%) system were conducted at the VIKA experimental installation at a saturation temperature of about 500 °C and a degassing temperature of 610 °C. It took about 41 min to reach pressure equilibrium at 500 °C. The hydrogen diffusion coefficient was calculated based on the Barrer formula and was 9.1 × 10−5 cm2/s at 500 °C. The maximum hydrogen content was recorded after the first sorption/desorption cycle and was 1.91 wt%. Due to the multiple thermal cyclic effects in the hydrogen medium, the predominantly two-phase (O + B2) alloy structure underwent transformation to form a new structure (O-AlNbTi2). In the phase composition of the Ti-25Al-25Nb (at.%) alloy, the formation of hydrides in the form of independent phases as a result of thermal cycling was not detected. Hydrogen absorption is most likely to be associated with the formation of an interstitial solution based on existing crystalline phases.- Book : 15(2)
- Pub. Date : 2025
- Page : pp.173-173
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2025
Column O/N2 ratio (∑O/N2), a physical quantity representing thermospheric disturbances, is influenced by solar extreme ultraviolet radiation flux (QEUV) changes. Investigating the correlation between these two factors is essential for understanding the evolution of the thermosphere. This study examines the correlation and periodic variations of ∑O/N2 and QEUV across different phases of solar activity, using data from the Global Ultraviolet Imager (GUVI) spanning from 2002 to 2022. A correlation analysis reveals a positive relationship between ∑O/N2 and QEUV. The function fitting results show that the magnitude of changes in ∑O/N2 due to QEUV variations is approximately 30% of the mean ∑O/N2. A wavelet analysis reveals their coherence in periodic components of 27-day, annual, and 11-year periods. These results are significant for studying the Sun–Earth coupling mechanism and understanding the impact of space weather on the thermosphere.- Book : 17(4)
- Pub. Date : 2025
- Page : pp.574-574
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2025
- Book : ()
- Pub. Date : 2025
- Page :
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2025
Abstract
We consider the possibility of indirect detection of dark sector processes by investigating a novel form of interaction between ambient dark matter (DM) and primordial black holes (PBHs). The basic scenario we envisage is that the ambient DM is “dormant”, i.e., it has interactions with the SM, but its potential for an associated SM signal is not realized for various reasons. We argue that the presence of PBHs with active Hawking radiation (independent of any DM considerations) can act as a catalyst in this regard by overcoming the aforementioned bottlenecks. The central point is that PBHs radiate all types of particles, whether in the standard model (SM) or beyond (BSM), which have a mass at or below their Hawking temperature. The emission of such radiation is “democratic” (up to the particle spin), since it is based on a coupling of sorts of gravitational origin. In particular, such shining of (possibly dark sector) particles onto ambient DM can then activate the latter into giving potentially observable SM signals. We illustrate this general mechanism with two specific models. First, we consider asymmetric DM, which is characterized by an absence of ambient anti-DM, and consequently the absence of DM indirect detection signals. In this case, PBHs can “resurrect” such a signal by radiating anti-DM, which then annihilates with ambient DM in order to give SM particles such as photons. In our second example, we consider the PBH emission of dark gauge bosons which can excite ambient DM into a heavier state (which is, again, not ambient otherwise), this heavier state later decays back into DM and photons. Finally, we demonstrate that we can obtain observable signals of these BSM models from asteroid-mass PBHs (Hawking radiating currently with ~
$$ \mathcal{O}\left(\textrm{MeV}\right) $$
O
MeV
temperatures) at gamma-ray experiments such as AMEGO-X.- Book : 2025(2)
- Pub. Date : 2025
- Page :
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2025
Abstract
The combination of plastic scintillators with Silicon
Photo-Multipliers (SiPMs) is widely used for detecting radiation in
high-energy astrophysics, particle physics, neutrino physics, or
medical physics. An example of application for this kind of
detectors are Compton polarimeters such as
POLAR-2 [1,2,3]
or LEAP [4,5,6] for which a
low-Z material is needed for the Compton effect to be dominant
down to as low energy as possible. Such detectors aim to measure low
energy Compton depositions in organic scintillators which produce
small amounts of optical light because of the low energy deposited
and the low scintillation efficiency, and for which optimizing the
instrumental optical properties consequently imperative.
The light collection efficiency of such a device was studied with a
focus on the POLAR-2 Gamma-Ray Burst polarimeter. POLAR-2 consists
of a segmented array of 6400 elongated plastic scintillators divided
into 100 modules, all read out by SiPMs. The conversion of incoming
γ-rays into readable signal goes through the production and
collection of optical light, which has been optimized both through
measurements and simulations. The optical elements of the POLAR-2
polarimeter prototype module were optically characterized and an
optical simulation based on Geant4 was developed to fully model its
optical performances. The results from simulations were used to
optimize the design and finally to verify its performance. The study
resulted in a detector capable of measuring energy depositions of
several keV. In addition, an important finding of this work is the
impact of the plastic scintillator surface roughness on the light
collection. It was found that a plastic scintillator with a higher
scintillation efficiency but made of a softer material, hence with a
rougher surface, was not necessarily the best option to optimize the
light collection. Furthermore, in order to optimize the optical
crosstalk between different channels, a production technique for
very thin (∼150 μm) and reusable silicone-based optical
coupling pads was developed. This method can be adapted to produce
either standalone pads or to directly mold a layer on any SiPM to be
later coupled to the scintillators.
After an introductory discussion describing the need of a large
scale GRB polarimeter like POLAR-2, the optical design and
characterization of the polarimeter modules that compose its
sensitive part are described. The Geant4-based optical simulations
of the POLAR-2 modules and the impact of the optical properties of
its various elements on the light collection efficiency of the
instrument are later presented. The work is finally summarized and
an outlook is given on the potential applications of the POLAR-2
optical characterization and simulation work to other experiments
employing similar elements.- Book : 20(02)
- Pub. Date : 2025
- Page : pp.P02010-P02010
- Keyword :
