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  • 2025

    Abstract Downward longwave irradiance DLF is one of the main components of the surface radiation balance (SRB), but its direct measurement is currently limited. Clouds modulate its behavior, and clear-sky DLF0 is predominant in composition of the final DLF value. It is shown that in mid-latitude and tropical atmospheres, DLF0 can be represented as the sum of fluxes from three distinct spectral regions: R1 (λ < 7.5 µm), R2 (7.5 to 14 µm), and R3 (λ > 14 µm). R1 and R3 are closely described by blackbody radiation at screen temperature (Tscr), while R2 exhibits a mean emissivity that primarily depends on total precipitable water (w). It is presented a simple yet consistent physically-based model (hereafter denoted by OLD0), suitable for estimation of DLF0 at ground level. Validation of OLD0 with ground-based data of a worldwide set of 21 stations shows fair accuracy with bias MBE lower than 6 W.m-2 and spread (standard deviation STD) lower than 12 W.m-2 for typical values DLF0 ~ 300-400 W.m-2, compatible with surface pyrgeometer measures. The proposed algorithm outperforms existing methods, achieving a mean bias error (in module |MBE|) of approximately 2.8 W.m-2. In contrast, other widely used algorithms typically exhibit |MBEs| ranging from 8.1 to 15.9 W.m-2.
    • Book : 40()
    • Pub. Date : 2025
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  • 2025


    • Book : ()
    • Pub. Date : 2025
    • Page : pp.1-3
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  • 2025

    The relativistic jets of gamma-ray bursts (GRBs) might be powered by a black-hole (BH) hyperaccretion system. The inherent asymmetry in these jets generates recoil forces, inducing oscillations and positional deviations of the BH from equilibrium. In this study, we explore the influence of different initial BH mass, spin, and mass accretion rate, as well as their evolutions on the dynamical properties of BH under the effect of asymmetric jets. Our results reveal that the initial mass and accretion rate significantly impact the BH’s acceleration, velocity, and displacement, while the different initial spin plays a negligible role in shaping the overall dynamical evolution. Additionally, we calculate the gravitational wave (GW) strains associated with the asymmetric jets, finding that the resulting GW signals are too weak to be detected, even for nearby GRBs. These findings provide critical insights into the dynamical response of BHs to asymmetric jets and the associated GW radiation, advancing our understanding of BH physics in GRBs.
    • Book : 11(2)
    • Pub. Date : 2025
    • Page : pp.43-43
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  • 2025


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    • Pub. Date : 2025
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  • 2025

    AbstractBackgroundSteatotic liver disease (SLD) is a potentially reversible condition but often goes unnoticed with the risk for end‐stage liver disease.PurposeTo opportunistically estimate SLD on lung screening chest computed tomography (CT) and investigate its prognostic value in heavy smokers participating in the National Lung Screening Trial (NLST).Material and methodsWe used a deep learning model to segment the liver on non‐contrast‐enhanced chest CT scans of 19,774 NLST participants (age 61.4 ± 5.0 years; 41.2% female) at baseline and on the 1‐year follow‐up scan if no cancer was detected. SLD was defined as hepatic fat fraction (HFF) ≥5% derived from Hounsfield unit measures of the segmented liver. Participants with SLD were categorized as lean (body mass index [BMI] < 25 kg/m2) and overweight (BMI ≥ 25 kg/m2). The primary outcome was all‐cause mortality. Cox proportional hazard regression assessed the association between (1) SLD and mortality at baseline and (2) the association between a change in HFF and mortality within 1 year.ResultsThere were 5.1% (1000/19,760) all‐cause deaths over a median follow‐up of 6 (range, 0.8–6) years. At baseline, SLD was associated with increased mortality in lean but not in overweight/obese participants as compared to participants without SLD (hazard ratio [HR] adjusted for risk factors: 1.93 [95% confidence interval 1.52–2.45]; p = 0.001). Individuals with an increase in HFF within 1 year had a significantly worse outcome than participants with stable HFF (HR adjusted for risk factors: 1.29 [1.01–1.65]; p = 0.04).ConclusionSLD is an independent predictor for long‐term mortality in heavy smokers beyond known clinical risk factors.
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    • Pub. Date : 2025
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  • 2025


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    • Pub. Date : 2025
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  • 2025

    Di-isopropyl methyl phosphonate (DIMP) has no major commercial uses but is a by-product or a precursor in the synthesis of the nerve agent sarin (GB). Also, DIMP is utilized as a simulant compound for the chemical warfare agents sarin and soman in order to test and calibrate sensitive IMS instrumentation that warns against the deadly chemical weapons. DIMP was measured from 2 ppbv (15 μg m−3) to 500 ppbv in the air using a pocket-held ToF ion mobility spectrometer, model LCD-3.2E, with a non-radioactive ionization source and ammonia doping in positive ion mode. Excellent sensitivity (LoD of 0.24 ppbv and LoQ of 0.80 ppbv) was noticed; the linear response was up to 10 ppbv, while saturation occurred at >500 ppbv. DIMP identification by IMS relies on the formation of two distinct peaks: the monomer M·NH4+, with a reduced ion mobility K0 = 1.41 cm2 V−1 s−1, and the dimer M2·NH4+, with K0 = 1.04 cm2 V−1 s−1 (where M is the DIMP molecule); positive reactant ions (Pos RIP) have K0 = 2.31 cm2 V−1 s−1. Quantification of DIMP at trace levels was also achieved by GC-MS over the concentration range of 1.5 to 150 μg mL−1; using a capillary column (30 m × 0.25 mm × 0.25 μm) with a TG-5 SilMS stationary phase and temperature programming from 60 to 110 °C, DIMP retention time (RT) was ca. 8.5 min. The lowest amount of DIMP measured by GC-MS was 1.5 ng, with an LoD of 0.21 μg mL−1 and an LoQ of 0.62 μg mL−1 DIMP. Our results demonstrate that these methods provide robust tools for both on-site and off-site detection and quantification of DIMP at trace levels, a finding which has significant implications for forensic investigations of chemical agent use and for environmental monitoring of contamination by organophosphorus compounds.
    • Book : 13(2)
    • Pub. Date : 2025
    • Page : pp.102-102
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  • 2025

    Background: Cell therapy demonstrates promising potential as a substitute therapeutic approach for liver cirrhosis. We have developed a strategy to effectively expand murine and human hepatocyte-derived liver progenitor-like cells (HepLPCs) in vitro. The primary objective of the present study was to apply HepLPCs to the treatment of liver cirrhosis and to elucidate the underlying mechanisms responsible for their therapeutic efficacy. Methods: The effects of allogeneic or xenogeneic HepLPC transplantation were investigated in rat model of liver cirrhosis. Liver tissues were collected and subjected to immunostaining to assess changes in histology. In vitro experiments used HSCs to explore the antifibrotic properties of HepLPC-secretomes and their underlying molecular mechanisms. Additionally, proteomic analysis was conducted to characterize the protein composition of HepLPC-secretomes. Results: Transplantation of HepLPCs resulted in decreased active fibrogenesis and net fibrosis in cirrhosis models. Apoptosis of HSCs was observed in vivo after HepLPC treatment. HepLPC-secretomes exhibited potent inhibition of TGF-β1-induced HSC activation and promoted apoptosis through signal transducer and activator of transcription (STAT)1-mediated pathways in vitro. Furthermore, synergistic effects between amphiregulin and FGF19 within HepLPC-secretomes were identified, contributing to HSC apoptosis and exerting antifibrotic effects via activation of the janus kinase-STAT1 pathway. Conclusions: HepLPCs have the potential to ameliorate liver cirrhosis by inducing STAT1-dependent apoptosis in HSCs. Amphiregulin and FGF19 are key factors responsible for STAT1 activation, representing promising novel therapeutic targets for the treatment of liver cirrhosis.
    • Book : 9(2)
    • Pub. Date : 2025
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  • 2025


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    • Pub. Date : 2025
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  • 2025

    Abstract. Shifting phosphorus (P) dynamics after wildfires can have cascading impacts from terrestrial to aquatic environments. However, it is unclear if post-fire responses are primarily driven by changes to the molecular composition of the charred material or from the transport of P-containing compounds. We used laboratory leaching experiments of Douglas-fir forest and sagebrush shrubland chars to examine how the potential mobility of P compounds is influenced by different burn severities. Burning produced a 6.9- and 29- fold increase in particulate P mobilization, but a 3.8- and 30.5- fold decrease in aqueous P released for Douglas-fir forest and sagebrush shrubland, respectively. P compound mobilization in the particulate phase was controlled by solid char total P concentrations while the aqueous phase was driven by solubility changes of molecular species. Nuclear magnetic resonance and X-ray absorption near edge structure on the solid chars indicated that organic orthophosphate monoester and diester species were thermally mineralized to inorganic P moieties with burning in both vegetation types. This coincided with the production of calcium- and magnesium-bound inorganic P compounds. With increasing burn severity there were systematic shifts in P concentration and composition— higher severity chars mobilized P compounds in the particulate phase, although the magnitude of change was vegetation specific. Our results indicate a post-fire transformation to both the composition of the solid charred material and to how P compounds are mobilized, which may influence its environmental cycling and fate.
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    • Pub. Date : 2025
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