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  • 2025

    With the advent of high repetition rate laser facilities, novel diagnostic tools compatible with these advanced specifications are required. This paper presents the design of an active gamma-ray spectrometer intended for these high repetition rate experiments, with particular emphasis on functionality within a PW level laser-plasma interaction chamber’s extreme conditions. The spectrometer uses stacked scintillators to accommodate a broad range of gamma-ray energies, demonstrating its adaptability for various experimental setups. In addition, it has been engineered to maintain compactness, electromagnetic pulse resistance, and ISO-5 cleanliness requirements while ensuring high sensitivity. The spectrometer has been tested in real conditions inside the PW-class level interaction chamber at the BELLA center, LBNL. The paper further details the calibration process, which utilizes a 60Co radioactive source, and describes the unfolding technique implemented through a stochastic minimization method.
    • Book : 96(2)
    • Pub. Date : 2025
    • Page :
    • Keyword :
  • 2025

    Abstract Spurious solar-wind effects are a potential noise source in future Laser Interferometer Space Antenna (LISA) measurements. One noise coupling mechanism is constrained by estimating solar-wind effects on acceleration noise in LISA Pathfinder (LPF). While LISA is designed for drag-free differential measurement, predicting the realistic impact both bounds the operational environment and assesses whether LISA could provide serendipitous space-weather observations. Data from NASA’s Advanced Composition Explorer (ACE), situated at the L1 Lagrange point, serves as a reliable source of solar-wind data. The data sets are compared over the 114-day time period from March 1, 2016 to June 23, 2016. This period gives the longest readily-available open data set, without interference from other commissioning activities. To evaluate space weather effects, the data from both satellites are formatted, gap-filled/interpolated, and Fast-Fourier Transformed for amplitude spectral density and coherence comparisons. Solar wind effects are not seen in a coherence plot between LPF and ACE; modest coherence in the planned LISA observational frequency band can be attributed to chance. This result indicates that measurable correlation due to solar-wind acceleration noise over 3-month timescales will be a negligible noise source. LISA is unlikely to inform solar wind measurements routinely. Another source of noise from the sun, solar radiation pressure, is estimated to impart greater acceleration noise, but has yet to be analyzed.
    • Book : ()
    • Pub. Date : 2025
    • Page :
    • Keyword :
  • 2025

    ABSTRACT We present a set of 11 two-temperature, radiative, general relativistic magnetohydrodynamic simulations of the black hole M87* in the magnetically arrested state, surveying different values of the black hole spin $a_*$. Our 3-D simulations self-consistently evolve the temperatures of separate electron and ion populations under the effects of adiabatic compression/expansion, viscous heating, Coulomb coupling, and synchrotron, bremsstrahlung, and inverse Compton radiation. We adopt a subgrid heating prescription from gyrokinetic simulations of plasma turbulence. Our simulations have accretion rates $\dot{M}=(0.5-1.5)\times 10^{-6}\dot{M}_{\rm Edd}$ and radiative efficiencies $\epsilon _{\rm rad}=$ 3–35 per cent. We compare our simulations to a fiducial set of otherwise identical single-fluid general relativistic magnetohydrodynamic (GRMHD) simulations and find no significant changes in the outflow efficiency or black hole spin-down parameter. Our simulations produce an effective adiabatic index for the two-temperature plasma of $\Gamma _{\rm gas}\approx 1.55$, larger than the $\Gamma _{\rm gas}=13/9$ value often adopted in single-fluid GRMHD simulations. We find moderate ion-to-electron temperature ratios in the 230 GHz emitting region of $R=T_{\rm i}/T_{\rm e}\,{\approx }\,5$. While total intensity 230 GHz images from our simulations are consistent with Event Horizon Telescope (EHT) results, our images have significantly more beam-scale linear polarization ($\langle |m|\rangle \approx 30~{{\rm per\ cent}}$) than is observed in EHT images of M87* ($\langle |m|\rangle \lt 10~{{\rm per\ cent}}$). We find a trend of the average linear polarization pitch angle $\angle \beta _2$ with black hole spin consistent with what is seen in single-fluid GRMHD simulations, and we provide a simple fitting function for $\angle \beta _2(a_*)$ motivated by the wind-up of magnetic field lines by black hole spin in the Blandford–Znajek mechanism.
    • Book : 537(3)
    • Pub. Date : 2025
    • Page : pp.2496-2515
    • Keyword :
  • 2025

    AbstractBackgroundSpinocerebellar ataxia type 2 (SCA2) is a rare, inherited neurodegenerative disease characterized by progressive deterioration in both motor coordination and cognitive function. Atrophy of the cerebellum, brainstem, and spinal cord are core features of SCA2; however, the evolution and pattern of whole‐brain atrophy in SCA2 remain unclear.ObjectiveWe undertook a multisite, structural magnetic resonance imaging (MRI) study to comprehensively characterize the neurodegeneration profile of SCA2.MethodsVoxel‐based morphometry analyses of 110 participants with SCA2 and 128 controls were undertaken to assess groupwise differences in whole‐brain volume. Correlations with clinical severity and genotype, and cross‐sectional profiling of atrophy patterns at different disease stages, were also performed.ResultsAtrophy in SCA2 versus controls was greatest (Cohen's d >2.5) in the cerebellar white matter (WM), middle cerebellar peduncle, pons, and corticospinal tract. Very large effects (d >1.5) were also evident in the superior cerebellar, inferior cerebellar, and cerebral peduncles. In the cerebellar gray matter (GM), large effects (d >0.8) were observed in areas related to both motor coordination and cognitive tasks. Strong correlations (|r| > 0.4) between volume and disease severity largely mirrored these groupwise outcomes. Stratification by disease severity exhibited a degeneration pattern beginning in the cerebellar and pontine WM in preclinical subjects; spreading to the cerebellar GM and cerebro‐cerebellar/corticospinal WM tracts; and then finally involving the thalamus, striatum, and cortex in severe stages.ConclusionThe magnitude and pattern of brain atrophy evolve over the course of SCA2, with widespread, nonuniform involvement across the brainstem, cerebellar tracts, and cerebellar cortex; and late involvement of the cerebral cortex and striatum. © 2025 The Author(s). Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.
    • Book : ()
    • Pub. Date : 2025
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  • 2025

    Abstract Fine-grained nuclear emulsion films have been developed as a tracking detector with nanometric spatial resolution to be used in direction-sensitive dark matter searches, thanks to novel readout technologies capable of exploiting this unprecedented resolution. Emulsion detectors are time insensitive. Therefore, a directional dark matter search with such detector requires the use of an equatorial telescope to absorb the Earth rotation effect. We have conducted for the first time a directional dark matter search in an unshielded location, at the sea level, by keeping an emulsion detector exposed for 39 days on an equatorial telescope mount. The observed angular distribution of the data collected during an exposure equivalent to 0.59 g days agrees with the background model and an exclusion plot was then derived in the dark matter mass and cross-section plane: cross-sections higher than 9.2 × 10-29 cm2 and 1.2 × 10-31 cm2 were excluded for a dark matter mass of 10 GeV/c 2 and 100 GeV/c 2, respectively. This is the first direction sensitive search for dark matter with a solid-state, particle tracking detector.
    • Book : 2025(02)
    • Pub. Date : 2025
    • Page : pp.012-012
    • Keyword :
  • 2025

    Background: The nuclear-encoded enzyme polymerase gamma (Pol-γ) is crucial in the replication of the mitochondrial genome (mtDNA), which in turn is vital for mitochondria and hence numerous metabolic processes and energy production in eukaryotic cells. Variants in the POLG gene, which encodes the catalytic subunit of Pol-γ, can significantly impair Pol-γ enzyme function. Pol-γ-associated disorders are referred to as POLG-spectrum disorders (POLG-SDs) and are mainly autosomal-recessively inherited. Clinical manifestations include muscle weakness and fatigue, and severe forms of the disease can lead to premature death in infancy, childhood, and early adulthood, often associated with seizures, liver failure, or intractable epilepsy. Here, we analyzed fibroblasts from a compound heterozygous patient with the established pathogenic variant c.2419C>T; p.(Arg807Cys) and a previously undescribed variant c.678G>C; p.(Gln226His) with a clinical manifestation compatible with POLG-SDs, sensory ataxic neuropathy, and infantile muscular atrophy. We conducted a battery of functional studies for Pol-γ and mitochondrial dysfunction on the patient’s fibroblasts, to test whether the novel variant c.678G>C; p.(Gln226His) may be causative in human disease. Aims/Methods: We analyzed skin-derived fibroblasts in comparison to a first-degree relative (the mother of the patient), an asymptomatic carrier harboring only the established c.2419C>T; p.(Arg807Cys) mutation. Assessments of mitochondrial function included measurements of mtDNA content, mRNA levels of mitochondrial genes, mitochondrial mass, and mitochondrial morphology. Case Presentation and Results: A 13-year-old male presented with symptoms starting at three years of age, including muscle weakness and atrophy in the lower extremities and facial muscles, which later extended to the upper limbs, voice, and back muscles, without further progression. The patient also reported fatigue and muscle pain after physical activity, with no sensory deficits. Extensive diagnostic tests such as electromyography, nerve conduction studies, muscle biopsy, and MRI were unremarkable. Exome sequencing revealed that he carried the compound heterozygous variants in POLG c.678G>C; p.(Gln226His) and c.2419C>T; p.(Arg807Cys), but no other potential genetic pathogenic causes. In comparison to a first-degree relative (his mother) who only carried the c.2419C>T; p.(Arg807Cys) pathogenic mutation, in vitro analyses revealed a significant reduction in mtDNA content (~50%) and mRNA levels of mtDNA-encoded proteins. Mitochondrial mass was reduced by approximately 20%, and mitochondrial interconnectivity within cells was impaired, as determined by fluorescence microscopy and mitochondrial staining. Conclusions: Our findings suggest that the c.678G>C; p.(Gln226His) variant, in conjunction with the c.2419C>T; p.(Arg807Cys) mutation, may compromise mtDNA replication and mitochondrial function and could result in clinically significant mitochondriopathy. As this study is based on one patient compared to a first-degree relative (but with an identical mitochondrial genome), the pathogenicity of c.678G>C; p.(Gln226His) of POLG should be confirmed in future studies, in particular, in conjunction with other POLG-variants.
    • Book : 16(2)
    • Pub. Date : 2025
    • Page : pp.198-198
    • Keyword :
  • 2025

    이 연구는 니가타현에 위치한 도쿄전력 가시와자키 가리와 원전 재가동을 둘러싼 원전 입지 지역의 현황을 희생의 시스템 논의를 토대로 검토했다. 원전 입지 지역에 대해서는 위험을 감수하는 희생을 강요당하는 반면, 그에 응당한 경제적인 혜택을 받는다는 등 쟁점이 존재하기 때문에, 사회적인 갈등을 야기하고 있는 해당 원전과 지역의 현황을 논할 필요가 있다. 주요 결과로는 첫 번째, 전력생산과 소비 측면에서 가시와자키 가리와 원전 입지 지역과 그 주변 지역에서는 불평등을 인식하고 있었으며, 원전에 대한 영향력이 제한된 상황에서 이를 극복하기 위한 움직임이 지역 정치와 시민사회 차원에서 관찰되었다. 두 번째, 일본 정부는 해당 원전의 안전성을 강조하며 재가동을 추진하려 하지만 원전의 위험은 이미 가시화된 상태이며, 이는 지자체와 시민들이 원전 관련 의사결정에 대한 참여를 요구하는 기제가 되고 있다. 세 번째, 원전이 지역경제에 어떠한 영향을 주는가에 대해서는 논쟁이 전개되고 있으며 지역 시민들의 인식도 혼란이 있었다. 이는 경제적 혜택과의 비교대상이 위험이라는 특성에서 기인한다. 이 연구에서는 원전 입지 지역과 주변 지역을 포함하여 ‘원전 영향 지역’이라는 개념을 제안했고, 가시와자키 가리와 원전 영향 지역 사례를 통해 지역과 주민 차원에서 기존의 수동적인 위치를 탈피하려는 실천이 이루어지고 있음을 확인할 수 있었다.
    • Pub. Date : 2025
    • Page : pp.280-311
    • Keyword :
  • 2025

    Extracorporeal shock wave lithotripsy (SWL) has been a well-known therapy since years ago, especially for renal stones less than 20 mm. This study compared the effectiveness of totally ultrasound-guided (US-guided) and fluoroscopy-guided (FS-guided) SWL in treating renal and ureteral stones. A protocol has been registered in PROSPERO databases for systematic reviews. A systematic literature search was conducted in five online databases (PubMed, ScienceDirect, EMBASE, ProQuest, and Scopus). We included all available articles that compared the effectiveness and safety of US-SWL to FS-SWL. A risk of bias assessment was done using Risk of Bias (Rob) Tools for randomized interventional studies and Risk of bias in non-randomized studies interventions (ROBINS-I) Tools for Non-randomized studies. The primary outcome was the stone-free rate, and the secondary outcome was the complication rate. Subgroup analyses were performed for adult and pediatric groups. A comprehensive literature search identified seven comparative articles that matched the criteria: two randomized trials and six retrospective cohort studies comprising 1,255 patients (609 using US-SWL). The results revealed a significant difference in overall stone-free rates between US-guided and FS-guided SWL RR 0.76(95% CI; 0.61-0.95, p=0.02) and in adults RR 0.76(95% CI; 0.60-0.96), but not children groups RR 0.68(95% CI; 0.24-1.88). US-SWL might be favourable due to the radiation-free procedure and real-time presentation. Complication rates were low, and no life-threatening complications were reported. In conclusion, US-guided SWL is more effective than FS-guided SWL for treating renal stones, with a low incidence of complications. Further randomized controlled trials with larger populations are needed to explore the comparison more accurately.
    • Book : 14()
    • Pub. Date : 2025
    • Page : pp.181-181
    • Keyword :
  • 2025

    Extraosseous osteosarcoma is a rare tumour that mostly affects males more than females. It accounts for 1.2% of all soft tissue sarcomas. It arises from soft tissues without direct attachment to the skeletal system and produces osteoid, bone, or chondroid material. Extraosseous osteosarcoma usually occurs middle-aged and elderly patients (5th–6th decade of life). Extraosseous osteosarcoma is highly aggressive. Due to rarity of this tumour, few data is available in the literature regarding the causes, symptom, and treatment of the disease hence this case report aims to focus some light on the rarity of this tumour along with its radiological features, presentations, and course of treatment. Here, we are discussing a rare case of extraosseous osteosarcoma of 35-year-old female with no prior history of trauma or radiation exposure.
    • Book : 12()
    • Pub. Date : 2025
    • Page : pp.1-4
    • Keyword :
  • 2025

    This article introduces a novel biodegradable metasurface-loaded mobile phone back cover designed to reduce electromagnetic exposure and enhance antenna performance. The cover operates across the low GHz band (2–8 GHz) and the millimeter-wave band (22–25.6 GHz), utilizing polylactic acid as an eco-friendly substrate. Integrated with a six-port multiple-input multiple-output (MIMO) antenna system, the cover achieves port isolation above 20 dB in both bands. Specific absorption rate (SAR) analysis, performed using a human head model, shows significant reductions in electromagnetic exposure—61.1% in the low GHz band (from 1.06 W/kg to 0.412 W/kg) and 55% in the millimeter wave band (from 2.061 W/kg to 0.917 W/kg). Additionally, the metasurface cover enhances antenna gain and increases impedance bandwidth by 20% in the low GHz band and 8.3% in the millimeter-wave band. A comparative study highlights superior SAR reduction and bandwidth improvement of a metasurface on a biodegradable substrate over one on a silicone substrate. Prototypes of the MIMO antenna and the proposed cover were fabricated and tested, revealing strong alignment between simulated and measured results. These findings highlight the potential of biodegradable metasurface-based covers to deliver high-performance, sustainable solutions for mobile communication devices.
    • Book : 18(4)
    • Pub. Date : 2025
    • Page : pp.730-730
    • Keyword :