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Background: A critical parameter of extracorporeal CO2 removal (ECCO2R) applications is the CO2 removal rate (VCO2). Low‐flow venovenous extracorporeal support with large‐size membrane lung remains undefined. This study aimed to evaluate the VCO2 of a low‐flow ECCO2R with large‐size membrane lung using a renal replacement therapy platform in an experimental animal model. Methods: Twelve healthy pigs were placed under mechanical ventilation and connected to an ECCO2R‐CRRT system (surface area = 1.8 m2; OMNIset®, BBraun, Germany). Respiratory settings were reduced to induce two degrees of hypercapnia. VCO2 was recorded under different combinations of PaCO2 (50–69 or 70–89 mm Hg), extracorporeal blood flow (ECBF; 200 or 350 mL/min), and gas flow (4, 6, or 10 L/min). Results: VCO2 increased with ECBF at all three gas flow rates. In severe hypercapnia, the increase in sweep gas flow from 4 to 10 L/min increased VCO2 from 86.38 ± 7.08 to 96.50 ± 8.71 mL/min at an ECBF of 350 mL/min, whereas at ECBF of 200 mL/min, any increase was less effective. But in mild hypercapnia, the increase in sweep gas flow result in significantly increased VCO2 at two ECBF. VCO2 increased with PaCO2 from 50–69 to 70–89 mm Hg at an ECBF of 350 mL/min, but not at ECBF of 200 mL/min. Post‐membrane lung PCO2 levels were similar for different levels of premembrane lung PCO2 (p = 0.08), highlighting the gas exchange diffusion efficacy of the membrane lung in gas exchange diffusion. In severe hypercapnia, the reduction of PaCO2 elevated from 11.5% to 19.6% with ECBF increase only at a high gas flow of 10 L/min (p < 0.05) and increase of gas flow significantly reduced PaCO2 only at a high ECBF of 350 mL/min (p < 0.05). Conclusions: Low‐flow venovenous extracorporeal ECCO2R‐CRRT with large‐size membrane lung is more efficient with the increase of ECBF, sweep gas flow rate, and the degree of hypercapnia. The influence of sweep gas flow on VCO2 depends on the ECBF and degree of hypercapnia. Higher ECBF and gas flow should be chosen to reverse severe hypercapnia. [ABSTRACT FROM AUTHOR]

PandaX-4T is a ton-scale dark matter direct detection experiment using a dual-phase TPC technique at the China Jinping Underground Laboratory. Various ultra-low background technologies have been developed and applied to material screening for PandaX-4T, including HPGe gamma spectroscopy, ICP-MS, NAA, radon emanation measurement system, krypton assay station, and alpha detection system. Low background materials were selected to assemble the detector. Surface treatment procedures were investigated to further suppress radioactive background. Combining measured results and Monte Carlo simulation, the total material background rates of PandaX-4T in the energy region of 1–25 keVee are estimated to be (9.9 ± 1.9) × 10−3 mDRU for electron recoil and (2.8 ± 0.6) × 10−4 mDRU for nuclear recoil. In addition, natKr in the detector is estimated to be < 8 ppt. [ABSTRACT FROM AUTHOR]

Data replication is widely used in cloud storage and data grid to improve the parallel service efficiency and the performance of system, which can promote the file availability and system load balancing, reducing the response time with multiple copies. But high volume of big data gives a new, enormous and rigorous challenge to data storage and business access of cloud storage, specially to the quality of cloud services. In this paper, a novel dynamic predicted replication strategy (DPRS) combining with the access frequency of files and prediction method is proposed to predict the future access of each file and calculating the optional number of replicas based on the real access and future access periodically. The experiment results show that DPRS can availably decrease the response time of a file request and reduce the additional cost of the cloud storage system simultaneously. [ABSTRACT FROM AUTHOR]

Since rock mass in many fields of rock engineering usually undergoes a cyclic heating and cooling process, it is very meaningful to investigate the variations of rock micro/macro physical and mechanical properties subjected to cyclic heating and cooling. However, due to the complex and invisible characteristics of rock microstructure, the effect of cyclic heating and cooling on rock macro/micro physical and mechanical properties still requires further investigation. In this study, to explore the microscopic mechanism underlying the variations of rock macroscopic properties during cyclic heating and cooling, uniaxial compression tests and P-wave velocity tests were conducted to obtain the macromechanical properties of red sandstone specimens subjected to varying numbers of heating and cooling cycles. Acoustic emission (AE) tests were also carried out to capture the variations in the microscopic damage process during each heating and cooling cycle. A scanning electron microscope and differential thermal analysis–thermal gravimetric analyzer were used to analyze the development of the microcracks and variations in the micrograin mass after each cyclic heating and cooling. The test results demonstrate that after being heated to 500 °C, some of the minerals (microcline, albite and calcite) in the sandstone decomposed and microcrocks developed due to the uneven thermal stress. When the sandstone was cooled in water, more microdefects were induced to the microstructure due to mineral transformations and uneven contractions, causing further deterioration to the integrity and compactness of the rock matrix. This phenomenon was also reflected in the uniaxial compression tests and AE tests. Due to the damage caused by each heating and cooling cycle, the AE hit rate decreased and the macrophysical and mechanical properties of rock deteriorated as the number of cycles increases. Comparison of the test results obtained from samples subjected to different heating and cooling cycles reveals that although each cycle could cause damage to the rock sample, the first and fifth cycles induced more severe damage, as indicated by the sharp decrease in the physical and mechanical properties of the rock after the first and fifth cycles. [ABSTRACT FROM AUTHOR]

Pulmonary embolism remains the third leading cause of human mortality after malignant tumors and myocardial infarction. Commonly available thrombolytic therapeutic agents suffer from the limitations of very short half-life, inadequate targeting, limited clot penetration, and a propensity for severe bleeding. Inspired by the trident, we developed the armor-piercing microcapsule (MC), fucoidan-urokinase-S-nitrosoglutathione-polydopamine@MC (FUGP@MC), which exhibited a triple combination of photothermal, mechanical and pharmacological thrombolysis for the therapeutic treatment of acute pulmonary embolism (APE). Briefly, the outermost fucoidan layer was utilized for targeting to the APE area. Programmed APE treatment was triggered by near-infrared (NIR) light irradiation. Photothermal thrombolytic therapy was carried out by photothermal conversion of polydopamine. The photothermal conversion broke the S-nitroso bond in S-nitrosoglutathione (GSNO) and produced large amounts of nitric oxide (NO) for mechanical thrombolysis, which subsequently disrupted the interfacial structure of microcapsule to stimulate the release of the urokinase (UK), leading to a triple synergistic thrombolytic effect. The results demonstrated that the embolization residual rate of FUGP@MC (contained ≈ 1452.5 IU/kg UK) group was significantly lower than that of UK (10,000 IU/kg) group (6.35 % VS 16.78 %). Remarkably, FUGP@MC demonstrated a reliable in vivo biosafety proficiency. In summary, trident-inspired armor-piercing microcapsule FUGP@MC reveals a potential avenue for advancing pulmonary embolism therapeutics and promises to be a safer alternative candidate to current drug approaches. • FUGP@MC exhibits programmed triple combination thrombolytic efficacy for the treatment of APE. • The embolization residual rate of FUGP@MC group was significantly lower than that of UK group (6.35 % VS 16.78 %). • FUGP@MC (contained ≈ 1452.5 IU/kg UK) group was treated with a lower dose for APE than the UK (10,000 IU/kg) group. • FUGP@MC demonstrated a reliable in vivo biosafety proficiency. [ABSTRACT FROM AUTHOR]

This paper investigates the influence of lead monoxide (PbO) content on the gamma ray attenuation coefficients of boro-telluro-phosphate glasses. The MCNP5 simulation code has been applied to estimate the mass attenuation coefficients (μ/ρ) of Sm3+ doped (60-x)B 2 O 3 -xPbO-14TeO 2 -10P 2 O 5 -7.5BaO-7.5CdO-1Sm 2 O 3 (x = 0, 10, 20, 30 and 40 wt%) glass system within 0.02–10 MeV photon energy range. The MCNP5 simulated results are accord with the theoretical XCOM results perfectly. The results show that the increasing content of PbO in the glass compositions can improve the gamma ray shielding capability of the studied glasses. With the biggest content of PbO in Pb40B20 glass, superior HVL and Z eff values are observed. The values of HVL for Pb40B20 glass vary from 0.0035 to 3.6824 cm, and the values of Z eff vary from 25.94 to 70.05 depending on the photon energy 0.02–10 MeV. In addition, the boro-telluro-phosphate glasses have been compared with types of commercial concretes and glasses in terms of HVL. • μ/ρ, Z eff , N eff, EBF, HVL and MFP for Sm3+ doped lead boro-telluro-phosphate glasses have been calculated. • The maximum value for μ/ρ and Z eff was found for the glasses with the highest PbO oxide. • MCNP code and XCOM software were used to calculate (μ/ρ) at different energies. • With the addition of PbO, the shielding properties of the prepared glasses were improved. [ABSTRACT FROM AUTHOR]

• A novel groove baffled gas channel for PEMFC is designed. • The optimal groove structure is obtained using the genetic algorithm. • The power consumption is 53.6 % lower than the rectangular baffled channel. • The maximum power density is 3.2 % higher compared to the conventional smooth channel. Proton exchange membrane fuel cell (PEMFC) is considered as a highly efficient and clean energy conversion technology, however, as the power density increases, conventional gas channels exhibit low mass transfer efficiency and high pumping power consumption. In this study, a novelly designed structure of gas channel with groove baffles is proposed, and a numerical simulation of three-dimensional, multi-physical field is conducted. The traditional smooth flow channel and the rectangular baffled channel are compared with the groove baffled channel. It is found that the pressure drop of the groove baffled channel is substantially less than the rectangular baffled channel, and the current density is higher than that of the traditional smooth flow channel. To obtain the optimal structural parameter of the groove baffle, the genetic algorithm is applied in this study. According to the results, the optimal comprehensive output performance of the cell is achieved for a groove height and width of 0.479 mm and 0.841 mm, respectively. At an operating potential of 0.5 V, the power density of PEMFC with the optimal structure is 3.2 % more than the traditional smooth flow channel. While compared with the rectangular baffled channel, the pumping power consumption is 53.6 % much lower and the overall efficiency is 2.1 % higher for the optimal groove baffled channel. This study will provide guidance for the design and optimization of the PEMFC's gas channels. [Display omitted] [ABSTRACT FROM AUTHOR]

Porcine epidemic diarrhea (PED), caused by the porcine epidemic diarrhea virus (PEDV), primarily affects the jejunum and ileum of pigs. Interferons, glycoproteins with high species specificity and potent antiviral activity, are crucial in defending against viral infections. Unlike other interferons, interferon-lambda (IFN-λ) mainly acts on mucosal epithelial cells and exhibits robust antiviral activity at mucosal surfaces. However, the high cost limits the use of naturally extracted interferons in farming. In this study, we expressed recombinant porcine interferon-lambda 1 (rpIFN-λ1) in eukaryotic cells, demonstrating effective antiviral activity against PEDV in Vero E6 and IPI-FX cells. In vivo , rpIFN-λ1 alleviated clinical symptoms and intestinal damage, enhanced antioxidant capacity, reduced inflammation, and significantly improved the survival rate of piglets following PEDV infection. Both in vitro and in vivo studies confirmed that rpIFN-λ1 upregulated interferon-stimulated genes (ISGs) via the JAK-STAT pathway, thereby exerting antiviral effects. In conclusion, rpIFN-λ1 significantly inhibited PEDV replication and alleviated clinical symptoms. The selectivity of rpIFN-λ1 for intestinal cells and its ability to reduce viral shedding suggest that this agent is a promising antiviral for enteric viruses such as PEDV. Our findings highlight rpIFN-λ1 as a cost-effective, efficient, and novel strategy for antiviral treatment of PEDV. [ABSTRACT FROM AUTHOR]

Porcine epidemic diarrhea (PED), caused by the porcine epidemic diarrhea virus (PEDV), primarily affects the jejunum and ileum of pigs. Interferons, glycoproteins with high species specificity and potent antiviral activity, are crucial in defending against viral infections. Unlike other interferons, interferon-lambda (IFN-λ) mainly acts on mucosal epithelial cells and exhibits robust antiviral activity at mucosal surfaces. However, the high cost limits the use of naturally extracted interferons in farming. In this study, we expressed recombinant porcine interferon-lambda 1 (rpIFN-λ1) in eukaryotic cells, demonstrating effective antiviral activity against PEDV in Vero E6 and IPI-FX cells. In vivo , rpIFN-λ1 alleviated clinical symptoms and intestinal damage, enhanced antioxidant capacity, reduced inflammation, and significantly improved the survival rate of piglets following PEDV infection. Both in vitro and in vivo studies confirmed that rpIFN-λ1 upregulated interferon-stimulated genes (ISGs) via the JAK-STAT pathway, thereby exerting antiviral effects. In conclusion, rpIFN-λ1 significantly inhibited PEDV replication and alleviated clinical symptoms. The selectivity of rpIFN-λ1 for intestinal cells and its ability to reduce viral shedding suggest that this agent is a promising antiviral for enteric viruses such as PEDV. Our findings highlight rpIFN-λ1 as a cost-effective, efficient, and novel strategy for antiviral treatment of PEDV. [ABSTRACT FROM AUTHOR]

In this study, a two-dimensional Voronoi element based – explicit numerical manifold method (VE-ENMM) is developed as a new approach to investigate the acoustic emission characteristics during the failure process of intact rocks. The micro-granular structures of the intact rocks are approximated by the random Voronoi polygons and the interactions among rock grains are interpreted using a modified interface contact model. A new acoustic emission (AE) monitoring technique considering the clustering effect of micro-cracks is developed based on the explicit time integration scheme of numerical manifold method. With the newly developed approach, a series of numerical simulations are carried out. Firstly, numerical uniaxial compressive and Brazilian tests are conducted to validate the new approach on simulating micro-/macro-mechanical behaviors of granite samples. After that, the acoustic event properties, such as time evolution, spatial clustering and frequency-magnitude distribution of AE events during the failure process under uniaxial compression are studied in details. Simulation results show that the development of acoustic emissions is in good consistence with the damage evolution process of the numerical model, which may help to reveal the micro-fracturing mechanism of intact rocks in terms of seismic energy dissipation. To further illustrate the capability of the developed approach in monitoring the failure process as well as failure characteristics during TBM tunnel excavation, an additional numerical simulation is conducted and the fracturing behaviors as well as the related AE properties of the surrounding rock mass during TBM tunnelling are investigated. [ABSTRACT FROM AUTHOR]

B 4 C/Al composites have been widely studied and used as neutron absorbing materials in various application fields because of its relatively simple preparation process, good mechanical properties, and low raw material prices. B 4 C content is the major factor affecting the neutron shielding performance of B 4 C/Al composites. A photo-neutron source driven by a 15 MeV electron linear accelerator has been used to measure the neutron shielding performance of the B 4 C/Al composite plates with B 4 C weight percentages of 16.85% and 31%, respectively. Based on the measurement result, the thermal neutron macroscopic cross sections of the B 4 C(16.85 wt%)/Al composite and B 4 C(31 wt%)/Al composite were 13.97 cm−1 and 25.58 cm−1, respectively. The measurement results showed that the B 4 C/Al composites have good shielding performance for neutrons with energies lower than 10 eV, especially for thermal neutrons, and the 1.02 mm thickness of B 4 C(31 wt%)/Al composite was able to absorb 90.91% of thermal neutrons. Experimental measurements were compared with calculation results. The experimental measurement result of the thermal neutron macroscopic absorption cross section was smaller than the calculated data, and the relative deviations of the experimental measurement results and calculation data of the thermal neutron macroscopic cross sections of B 4 C(16.85 wt%)/Al and B 4 C(31 wt%)/Al composites were −13.65% and −12.52%, respectively. The Monte Carlo N-Particle Transport code was used to calculate the neutron shielding performance of B 4 C/Al with different B 4 C content, and the shielding performance of the B 4 C/Al composites for low-energy neutrons was approximately linearly proportional to the B 4 C content, especially for the thermal neutron. •The B 4 C/Al had a good shielding performance for low-energy neutrons. •The neutron shielding performance of the B 4 C/Al depends on the B 4 C content. •The size of B 4 C impact on the neutron shielding performance of the B 4 C/Al. [ABSTRACT FROM AUTHOR]