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  • 2025

    The solar-assisted heat pump drying (SAHPD) system uniquely incorporates solar-heating refrigerant through hot water from solar evacuated tubes, offering distinct advantages. This study analyzed three experimental setups: a heat pump dryer (HPD) without solar assistance, SAHPD configuration 1 (C1-SAHPD) with solar-heated refrigerant at the discharge line, and SAHPD configuration 2 (C2-SAHPD) with solar-heated refrigerant between condensers, both for performance and economic viability. The experiments maintained consistent parameters, including 5.5 kg of Pandan leaf (Pandanus amaryllifolius), an airflow rate of 0.135 kg/s, and a refrigerant operating pressure of 9.65 bar. The SAHPDs operated when the hot water temperature in the storage tank reached between 70°C and 90°C, with a daily average radiation intensity ranging from 0.670 to 1.102 kW/m² for heating the water. The study revealed average coefficients of performance (COPavg) of 5.34, 5.43, and 6.53 for HPD, C1-SAHPD, and C2-SAHPD, respectively. The specific moisture extraction rate (SMER) for HPD was 2.64, while C1-SAHPD and C2-SAHPD had SMERs of 1.88 and 2.71 at solar fractions of 0.34 and 0.45, respectively. Notably, C2-SAHPD reduced electricity consumption by 46%. The payback period for drying 11 kg of Pandan leaves per day was 4.56 months for HPD, 4.32 months for C1-SAHPD, and 3.84 months for C2-SAHPD. The study concluded that C2-SAHPD was the most efficient dryer system for Pandan leaves based on its higher efficiency, SMER, and cost recovery. Additionally, the performance optimization presented in this study contributed to developing a novel technique for classifying dryer technologies.
    • Book : 37(1)
    • Pub. Date : 2025
    • Page : pp.349-368
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  • 2025

    The present review highlights the role of computed tomography (CT), CT colonography (CTC), and magnetic resonance imaging (MRI) in the diagnosis, staging, response evaluation, and follow-up of colorectal cancer. For a CT scan, prior bowel preparation is required. This is done to enhance imaging of the colon with the use of oral or rectal contrast agents. Negative contrast like air or carbon dioxide are helpful in detecting polyps and masses by distending the colon. Virtual colonoscopy offers a lower-radiation alternative for polyp and cancer detection. Intravenous contrast administration with arterial and venous phase CT images is also important in complete staging of a known case of colon cancer and for evaluation of residual/recurrent disease. With respect to MRI, high-resolution T2-weighted images in multiple planes are important, with diffusion-weighted imaging (DWI) sequences being important for restaging. Intravenous contrast is not generally recommended. Contrast-enhanced CT and MRI are used for nodal and distant metastasis staging, with special attention to the pelvic side wall nodes. Positron emission tomography (PET) CT is to be considered for further evaluation if the findings are unclear and recurrence is suspected.
    • Book : ()
    • Pub. Date : 2025
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  • 2025

    Chiral effective field theory (χEFT) has proved to be a powerful microscopic framework for predicting the properties of neutron-rich nuclear matter with quantified theoretical uncertainties up to about twice the nuclear saturation density. Tests of χEFT predictions are typically performed at low densities using nuclear experiments, with neutron star (NS) constraints only being considered at high densities. In this work, we discuss how asteroseismic quasinormal modes within NSs could be used to constrain specific matter properties at particular densities not just the integrated quantities to which bulk NS observables are sensitive. We focus on the crust-core interface mode, showing that measuring this mode's frequency would provide a meaningful test of χEFT at densities around half the saturation density. Conversely, we use nuclear matter properties predicted by χEFT to estimate that this mode's frequency is around 185±50Hz. Asteroseismic observables such as resonant phase shifts in gravitational-wave signals and multimessenger resonant shattering flare timings, therefore, have the potential to provide useful tests of χEFT. Published by the American Physical Society 2025
    • Book : 111(1)
    • Pub. Date : 2025
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  • 2025

    Background: Intrahepatic cholangiocarcinoma (ICC), a malignancy originating from the epithelial cells of bile ducts, has shown a notable rise in its incidence over the years. It ranks as the second most frequent primary liver cancer after hepatocellular carcinoma. This study investigates how independent prognostic factors, specifically, age and tumor stage, interact to impact mortality in ICC patients. Furthermore, it examines the clinical features, survival rates, and prognostic indicators of ICC cases diagnosed between 2010 and 2017. Methods: Using data from 5083 patients obtained from the Surveillance, Epidemiology, and End Results (SEER) database, this study evaluated demographic and clinical factors alongside overall mortality (OM) and cancer-specific mortality (CSM). Variables achieving a p-value below 0.1 in univariate Cox regression analysis were incorporated into multivariate Cox regression models to identify independent prognostic factors. Hazard ratios (HRs) exceeding 1 were interpreted as markers of poor prognosis. Additionally, this study explored the interaction between age and tumor stage in shaping survival outcomes. Results: The multivariate Cox proportional hazards analysis indicated higher OM in males (HR = 1.19, 95% CI: 1.12–1.26, p < 0.01) and residents of metropolitan counties with populations exceeding 250,000 (HR = 1.15, 95% CI: 1.01–1.31, p < 0.05). Conversely, lower OM was observed in individuals aged 40–59 years (HR = 0.58, 95% CI: 0.38–0.89, p < 0.05), those aged 60–79 years (HR = 0.65, 95% CI: 0.43–0.98, p < 0.05), and patients who received radiation therapy (HR = 0.78, 95% CI: 0.72–0.85, p < 0.01), chemotherapy (HR = 0.54, 95% CI: 0.51–0.58, p < 0.01), or surgery (HR = 0.29, 95% CI: 0.26–0.31, p < 0.01). For CSM, males exhibited higher risks (HR = 1.17, 95% CI: 1.10–1.25, p < 0.01), as did individuals in metropolitan counties with populations over 250,000 (HR = 1.18, 95% CI: 1.03–1.35, p < 0.05). Reduced CSM was observed in patients aged 40–59 years (HR = 0.52, 95% CI: 0.34–0.79, p < 0.01), those aged 60–79 years (HR = 0.57, 95% CI: 0.38–0.86, p < 0.01), and those undergoing radiation therapy (HR = 0.76, 95% CI: 0.70–0.83, p < 0.01), chemotherapy (HR = 0.55, 95% CI: 0.51–0.59, p < 0.01), or surgery (HR = 0.27, 95% CI: 0.25–0.30, p < 0.01). When examining the interaction between age and tumor stage, higher OM was observed in patients aged 40–59 with tumors involving lymph nodes (HR = 1.26, 95% CI: 1.14–2.67, p < 0.05). Similarly, CSM was elevated in patients aged 40–59 with lymph node involvement alone (HR = 2.60, 95% CI: 1.26–5.36, p < 0.05) or with direct spread (HR = 2.81, 95% CI: 1.04–7.61, p < 0.05). Among those aged 60–79, higher CSM was noted in cases with lymph node involvement only (HR = 2.24, 95% CI: 1.11–4.50, p < 0.05) or lymph node involvement accompanied by direct extension (HR = 2.93, 95% CI: 1.10–7.82, p < 0.05). Conclusions: This retrospective analysis, utilizing data from the SEER database, provides new insights into mortality patterns in intrahepatic cholangiocarcinoma (ICC). This study identifies a significant interplay between two key prognostic factors, emphasizing their collective role in influencing mortality outcomes. Despite the predominance of advanced-stage diagnoses, our analysis underscores the substantial survival benefits associated with treatment interventions, with surgical procedures demonstrating the most pronounced impact. These findings highlight the importance of recognizing patients who may benefit from timely and intensive therapeutic strategies. Furthermore, the results underscore the need for future prospective randomized studies to deepen our understanding of these interactions in ICC, particularly as advancements in precision oncology continue to refine patient care.
    • Book : 13(2)
    • Pub. Date : 2025
    • Page : pp.31-31
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  • 2025

    The yield of photovoltaic hydrogen production systems is influenced by a number of factors, including weather conditions, the cleanliness of photovoltaic modules, and operational efficiency. Temporal variations in weather conditions have been shown to significantly impact the output of photovoltaic systems, thereby influencing hydrogen production. To address the inaccuracies in hydrogen production capacity predictions due to weather-related temporal variations in different regions, this study develops a method for predicting photovoltaic hydrogen production capacity using the long short-term memory (LSTM) neural network model. The proposed method integrates meteorological parameters, including temperature, wind speed, precipitation, and humidity into a neural network model to estimate the daily solar radiation intensity. This approach is then integrated with a photovoltaic hydrogen production prediction model to estimate the region’s hydrogen production capacity. To validate the accuracy and feasibility of this method, meteorological data from Lanzhou, China, from 2013 to 2022 were used to train the model and test its performance. The results show that the predicted hydrogen production agrees well with the actual values, with a low mean absolute percentage error (MAPE) and a high coefficient of determination (R2). The predicted hydrogen production in winter has a MAPE of 0.55% and an R2 of 0.985, while the predicted hydrogen production in summer has a slightly higher MAPE of 0.61% and a lower R2 of 0.968, due to higher irradiance levels and weather fluctuations. The present model captures long-term dependencies in the time series data, significantly improving prediction accuracy compared to conventional methods. This approach offers a cost-effective and practical solution for predicting photovoltaic hydrogen production, demonstrating significant potential for the optimization of the operation of photovoltaic hydrogen production systems in diverse environments.
    • Book : 18(3)
    • Pub. Date : 2025
    • Page : pp.543-543
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  • 2025


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    • Pub. Date : 2025
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  • 2025

    Conventional circularly polarized antennas have been employed to deliver microwave illumination in microwave-induced thermoacoustic tomography (TAT). However, these antennas exhibit several limitations in TAT systems, including low efficiency, poor axial ratio (AR) roundness, and narrow axial ratio beamwidth (ARBW). These issues lead to uniform radiation only within a relatively confined area, thereby restricting their effectiveness in clinical applications such as breast imaging. To address these issues, we propose a novel planar slot array antenna that offers a wide ARBW and improved axial ratio (AR) roundness, enabling homogeneous illumination over a larger field. We validated this approach both theoretically and experimentally. Tissue-mimicking phantoms were imaged, demonstrating that the antenna generated a circularly polarized electric field as well as a uniformly illuminated area. These advantages make the antenna proposed in this paper more suitable for clinical imaging compared to traditional microwave radiating antennas.
    • Book : 17(2)
    • Pub. Date : 2025
    • Page : pp.197-197
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  • 2025

    Abstract Hot axions, thermally produced in the Early Universe, would contribute to dark radiation and are thus subject to present and future constraints from N eff. In this paper we quantify the contribution to N eff and its uncertainty in models with axion-gluon couplings from thermal dynamics above the QCD transition. In more detail, we determine the leading-order thermal axion production rate for axion momenta of the order of the temperature adopting three different schemes for the incorporation of the collective dynamics of soft gluons. We show how these three schemes extrapolate differently into the regime of softer axion production, thus giving us a first quantitative handle on the theory uncertainty of the rate. Upon solving the Boltzmann equation, we find that this theory uncertainty translates to an uncertainty of order 0.002 for the contribution to N eff prior to the QCD crossover. The uncertainty from common momentum-averaged approximations to the Boltzmann equation is smaller. We also discuss how QCD transition dynamics would need to be integrated into our results and we show how existing rate determinations in the literature based on gauge-dependent resummations are problematic.
    • Book : 2025(1)
    • Pub. Date : 2025
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  • 2025

    AbstractWe investigate if mesoscale self‐organisation of trade cumuli in 150 km‐domain large‐eddy simulations modifies the top‐of‐atmosphere radiation budget relative to 10 km‐domain simulations, across 77 characteristic, idealized environments. In large domains, self‐generated mesoscale circulations produce fewer, larger and deeper clouds, raising the cloud albedo. Yet they also precipitate more than small‐domain cumuli, drying and warming the cloud layer, and reducing cloud cover. Consequently, large domains cool slightly less through the shortwave cloud‐radiative effect, and slightly more through clear‐sky outgoing longwave radiation, for a net cooling (−0.5 W ). This cooling is generally smaller than the large‐domain radiation's sensitivity to large‐scale meteorological variability, which is similar in small‐domain simulations and observations. Hence, mesoscale self‐organisation would not alter weak trade‐cumulus feedback estimates previously derived from small‐domain simulations. We explain this with a symmetry hypothesis: ascending and descending branches of mesoscale circulations symmetrically increase and reduce cloudiness, weakly modifying the mean radiation budget.
    • Book : 52(3)
    • Pub. Date : 2025
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  • 2025


    • Book : ()
    • Pub. Date : 2025
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